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University of Saskatchewan
1.
Cordova Alcivar, Pedro Luis 1990-.
Fretting fatigue in steel bolted connections.
Degree: 2018, University of Saskatchewan
URL: http://hdl.handle.net/10388/11851 
► The steelwork in a potash mineshaft is subjected to repeated lateral loads due to the lateral motion of the cages and skips that transport personnel,…
(more)
▼ The steelwork in a potash mineshaft is subjected to repeated lateral loads due to the lateral motion of the cages and skips that transport personnel, ore, and equipment up and down the mineshaft. As a result, the steel assemblies, including their bolted connections, must be designed to prevent failure due to fatigue. However, due to uncertainty regarding the fatigue behaviour of the connections, designers must take a very conservative approach, which could result in an uneconomical design.
The main objective of this research was to determine the fatigue behaviour of slipcritical bolted connections when different bolt types and surface finishes are used. A325 high strength bolts and C50LR Huck tension control bolts were used as the different bolt types. As-received mill scale steel plates (Class A surface finish) and blast-cleaned surfaces with a Cathacoat 302HB coating (Class B surface finish) were used as the different finishes. A digital image correlation system, as well as optical and scanning electron microscopic examination were used to characterize the modes of failure of the specimens.
Bolted connections assembled with the Class A surface finish failed due to fretting fatigue damage and crack initiation took place some distance away from the hole in a partial slip region between a stick region adjacent to the bolt hole and a gross slip region further from the hole where the relative motion between the plates was highest. On the other hand, specimens with the Class B surface finish failed due to bending fatigue caused by the eccentricity between the tension forces in the plates in the single-lap bolted joints, and crack initiation took place at the hole edge where the stress concentration was higher. The bolt type did not have a large effect on the fatigue behaviour, except that the tension in the tension control bolts may have been slightly higher, resulting in a slight improvement in the fatigue life. In general, the fatigue life results were lower than those in the S-N curve given in CSA S16-14, differing from the standard curve by an increasing margin as the stress range increased due to the effects of bending within the specimens.
Advisors/Committee Members: Wegner, Leon, Boulfiza, Mohamed, MacPhedran, Ian, Akindele, Odeshi.
Subjects/Keywords: Fretting fatigue; slip-critical connections; partial slip regime; steel bolted connections
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APA (6th Edition):
Cordova Alcivar, P. L. 1. (2018). Fretting fatigue in steel bolted connections. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/11851
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Cordova Alcivar, Pedro Luis 1990-. “Fretting fatigue in steel bolted connections.” 2018. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/11851.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Cordova Alcivar, Pedro Luis 1990-. “Fretting fatigue in steel bolted connections.” 2018. Web. 27 Feb 2021.
Vancouver:
Cordova Alcivar PL1. Fretting fatigue in steel bolted connections. [Internet] [Thesis]. University of Saskatchewan; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/11851.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Cordova Alcivar PL1. Fretting fatigue in steel bolted connections. [Thesis]. University of Saskatchewan; 2018. Available from: http://hdl.handle.net/10388/11851
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
2.
Ohalele, Henry Uche.
Evaluating Effects of Heat Fluxes and Duration on Performance of Firefighters’ Protective Clothing Using Destructive and Non Destructive Methods.
Degree: 2020, University of Saskatchewan
URL: http://hdl.handle.net/10388/12908
► Firefighters rely on their protective clothing to provide them with maximum protection while carrying out their duties. New pieces of firefighters’ protective clothing are constructed…
(more)
▼ Firefighters rely on their protective clothing to provide them with maximum protection while carrying out their duties. New pieces of firefighters’ protective clothing are constructed to meet various standards and regulations. However, degradation will occur over time due to a number of factors. As most textile tests are destructive, non-destructive test methods are needed to monitor degradation levels and provide useful data for determining the time to retirement especially given the high replacement cost of firefighters’ protective clothing. The focus of this study was thermal ageing of outer shell fabrics due to high heat fluxes including the effect of the duration of exposure. Tensile strength of three Kevlar/Polybenzimidazole (PBI) outer shell fabrics was measured before and after exposures to heat fluxes of 10 to 40 kW/m2 in the cone calorimeter for 30, 60, 90, 120, and 300s durations. Fabrics exposed to a low heat flux of 10 kW/m2 did not show significant change in the tensile strength. For higher exposure levels of 20 to 40 kW/m2, the fabric strength fell below standard requirements (i.e. less than 623N) for the RS Black and RS Natural fabrics while the remaining strength for SCI PBI Max fabrics stayed above 623N up until the 40kW/m2 heat flux exposure.
The reflectance and transmittance properties of fabrics were measured using near infrared (NIR) spectroscopy and correlations with the remaining tensile strength of the fabrics were developed. Changes in the NIR spectrum over the 800-2000 nm wavelength range along with fabric temperature measurements, thermogravimetric analysis and optical microscopy were used to examine the effects of heat flux and duration of exposure on performance of these fabrics. Methods of analyzing NIR data, used in the group’s previous research were evaluated: percentage shift in absorbance, absorbance feature characteristic changes (area and prominence) and slope change based on a normalized difference index method. Results from the normalized difference index slope change method showed a consistent relation to the original tensile strength for all three types of fabric investigated. Finally, it is expected that results from this research will be used for developing practical devices for non-destructive evaluations of firefighters’ protective clothing.
Advisors/Committee Members: Bugg, James, Odeshi, Akindele, Boulfiza, Mohamed.
Subjects/Keywords: Firefighters; protective clothing; non-destructive testing; near infrared spectroscopy; tensile strength testing; aging
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APA (6th Edition):
Ohalele, H. U. (2020). Evaluating Effects of Heat Fluxes and Duration on Performance of Firefighters’ Protective Clothing Using Destructive and Non Destructive Methods. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12908
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ohalele, Henry Uche. “Evaluating Effects of Heat Fluxes and Duration on Performance of Firefighters’ Protective Clothing Using Destructive and Non Destructive Methods.” 2020. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/12908.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ohalele, Henry Uche. “Evaluating Effects of Heat Fluxes and Duration on Performance of Firefighters’ Protective Clothing Using Destructive and Non Destructive Methods.” 2020. Web. 27 Feb 2021.
Vancouver:
Ohalele HU. Evaluating Effects of Heat Fluxes and Duration on Performance of Firefighters’ Protective Clothing Using Destructive and Non Destructive Methods. [Internet] [Thesis]. University of Saskatchewan; 2020. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/12908.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ohalele HU. Evaluating Effects of Heat Fluxes and Duration on Performance of Firefighters’ Protective Clothing Using Destructive and Non Destructive Methods. [Thesis]. University of Saskatchewan; 2020. Available from: http://hdl.handle.net/10388/12908
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
3.
Arjmand, Hanieh 1988-.
Quantitative Computed Tomography Based Finite Element Modeling of Normal and Osteoarthritic Knees: In vivo Precision and Preliminary Comparisons.
Degree: 2016, University of Saskatchewan
URL: http://hdl.handle.net/10388/7497
► Osteoarthritis (OA) is a debilitating joint disease which affects nearly 85% of the Canadian population over 75 years of age. OA not only affects cartilage,…
(more)
▼ Osteoarthritis (OA) is a debilitating joint disease which affects nearly 85% of the Canadian population over 75 years of age. OA not only affects cartilage, but it also alters subchondral bone (bone underlying cartilage). Altered subchondral bone could be related to OA initiation, progression, and OA-related pain. To help clarify the role of subchondral bone in OA, accurate in vivo methods are needed to monitor subchondral bone mechanical property variations in people living with OA. Subject-specific finite element (FE) modeling has potential to investigate the role of mechanical properties of subchondral bone in OA. However, associated precision errors of FE-derived mechanical properties are not known.
The objectives of this study were to 1) develop a subject-specific FE modeling methodology for OA and normal knees, 2) determine the in vivo precision of FE-derived stress/strain distributions and stiffness of the proximal tibia, and 3) determine whether FE-derived metrics discriminate normal and OA knees.
Subject-specific FE models were developed for 14 participants (7 OA, 7 normal) with three repeated CT images of knee joint. Von-Mises stress and strain, minimum principal stress and strain, plus structural stiffness outcomes were acquired for each proximal tibia image. Root mean square coefficient of variations (CV%) were used to assess in vivo precision of the FE-based outcomes. Comparisons between OA and normal groups were performed using unpaired t-tests for normally distributed outcomes, and Mann-Whitney U-tests for not normally distributed outcomes.
For all the outcomes the average CV% was less than 6.1%. On average, von-Mises stress and minimum principal stress were respectively 65% and 70% higher in OA versus normal knees whereas strain values did not differ. No difference was observed in stiffness values.
Thesis results indicate that FE modeling could be used to precisely quantify and differentiate mechanical property variations in normal and OA knees, in vivo. Results suggest that OA and normal bone exhibit dissimilar stress levels but similar strain levels, likely indicating adaptation of bone in response to altered joint mechanics with OA.
Advisors/Committee Members: Szyszkowski, Walerian, Boulfiza, Mohamed, Stavness, Ian, Simonson, Carey J..
Subjects/Keywords: Finite element modeling; osteoarthritis; subchondral bone; proximal tibia; knee joint.
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APA (6th Edition):
Arjmand, H. 1. (2016). Quantitative Computed Tomography Based Finite Element Modeling of Normal and Osteoarthritic Knees: In vivo Precision and Preliminary Comparisons. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/7497
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Arjmand, Hanieh 1988-. “Quantitative Computed Tomography Based Finite Element Modeling of Normal and Osteoarthritic Knees: In vivo Precision and Preliminary Comparisons.” 2016. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/7497.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Arjmand, Hanieh 1988-. “Quantitative Computed Tomography Based Finite Element Modeling of Normal and Osteoarthritic Knees: In vivo Precision and Preliminary Comparisons.” 2016. Web. 27 Feb 2021.
Vancouver:
Arjmand H1. Quantitative Computed Tomography Based Finite Element Modeling of Normal and Osteoarthritic Knees: In vivo Precision and Preliminary Comparisons. [Internet] [Thesis]. University of Saskatchewan; 2016. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/7497.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Arjmand H1. Quantitative Computed Tomography Based Finite Element Modeling of Normal and Osteoarthritic Knees: In vivo Precision and Preliminary Comparisons. [Thesis]. University of Saskatchewan; 2016. Available from: http://hdl.handle.net/10388/7497
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
4.
Borugadda, Anil K 1975-.
EXTENDING THE ADJUSTING KINEMATIC PARAMETER APPROACH TO SPATIAL ROBOTIC MECHANISMS.
Degree: 2019, University of Saskatchewan
URL: http://hdl.handle.net/10388/12311
► Robotic mechanisms refer to mechanisms that include at least one varying speed motor (servomotor). Dynamic balancing is a critical issue in designing robotic mechanisms, which…
(more)
▼ Robotic mechanisms refer to mechanisms that include at least one varying speed motor (servomotor). Dynamic balancing is a critical issue in designing robotic mechanisms, which affects their accuracy and efficiency. The force and moment from robotic mechanisms can cause vibration motions on the base, which is called the shaking force and shaking moment (including torque), while at the same time causes “small” vibration motions on the body of the mechanism. Several well-known methods are available for decades for balancing the shaking force and shaking moment, including the counter-weight (CW) method, add-of-spring (AOS) method, add-of-linkage (AOL), and adjusting kinematic parameter (AKP). AKP was developed in our group in 1990s; however, it is only applicable to planar robotic mechanisms.
The primary objective of this thesis was to extend AKP to spatial robotic mechanisms. A spherical parallel robotic mechanism, which is a type of spatial robotic mechanisms, was chosen as a study vehicle due to their relatively simple kinematics and dynamics. The mechanism is symmetrical consisting of three legs and one mobile platform, where the end effector (e.g., camera orienting device) is mounted. Each leg contains a lower link and an upper link. The equations for force balancing using AKP were derived by (1) writing the position vectors of the COM of mechanisms with respect to the reference point ‘O’, (2) writing the expression of the COM into a form that includes the time-dependent term (Bi) and the non time-dependent term (Ai), and (3) letting all Bi be zero, i.e., Bi=0, which are the equations for force balancing. Simulation was performed by the software called SPACAR developed at TU Delft. The simulation results showed the effectiveness of the AKP approach to spatial spherical mechanisms for force balancing.
Another objective of this thesis was to use a combination of AKP and CW to dynamic balance a spherical mechanism. Dynamic balancing includes both force and moment balancing. The condition of moment balancing is that the total angular momentum of the mechanism with respect to a reference point remains zero. The equations for moment balancing were derived with three steps: (1) letting the angular momentum of the mechanism with respect to the center point to zero, which results into an equation; (2) writing this equation into a format that the time-dependent term (Bi) and the term (Ai) that includes the dimension and mass distribution are separate, like A0 + A1B1+A2B2+…+AnBn; (3) letting all Ai be zero. Using SPACAR as the simulation tool, the results again showed the effectiveness of the AKP approach to dynamic balancing for spatial mechanisms.
The final objective was to optimize the mechanism which has been force balanced for the minimal shaking moment; this problem is also called partial shaking moment balancing. The problem was formulated by considering the minimization of shaking moment as an objective function while the force balancing equation as a constraint equation. The variables in the optimization…
Advisors/Committee Members: Zhang, Chris, Wiens, Travis, Fotouhi, Reza, Boulfiza, Mohamed.
Subjects/Keywords: dynamic balancing; spatial robotic mechanisms
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APA (6th Edition):
Borugadda, A. K. 1. (2019). EXTENDING THE ADJUSTING KINEMATIC PARAMETER APPROACH TO SPATIAL ROBOTIC MECHANISMS. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12311
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Borugadda, Anil K 1975-. “EXTENDING THE ADJUSTING KINEMATIC PARAMETER APPROACH TO SPATIAL ROBOTIC MECHANISMS.” 2019. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/12311.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Borugadda, Anil K 1975-. “EXTENDING THE ADJUSTING KINEMATIC PARAMETER APPROACH TO SPATIAL ROBOTIC MECHANISMS.” 2019. Web. 27 Feb 2021.
Vancouver:
Borugadda AK1. EXTENDING THE ADJUSTING KINEMATIC PARAMETER APPROACH TO SPATIAL ROBOTIC MECHANISMS. [Internet] [Thesis]. University of Saskatchewan; 2019. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/12311.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Borugadda AK1. EXTENDING THE ADJUSTING KINEMATIC PARAMETER APPROACH TO SPATIAL ROBOTIC MECHANISMS. [Thesis]. University of Saskatchewan; 2019. Available from: http://hdl.handle.net/10388/12311
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
5.
Zacharias, Daniel.
Hardware-in-the-Loop Prototype of a Negative Sequence Based Scheme for Turn-to-Turn Fault Detection in Transformers.
Degree: 2013, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2013-12-1347
► During the course of a transformer's operational life, it experiences many challenges to its insulation. Chemical stresses, such as moisture in insulating oil, deteriorate insulation…
(more)
▼ During the course of a transformer's operational life, it experiences many challenges to its insulation. Chemical stresses, such as moisture in insulating oil, deteriorate insulation chemically. Mechanical stresses and thermal stresses, such as those experienced during a large external fault, also contribute to weakening a transformer's insulation. Once these stresses have weakened the insulation to the point of breakdown, a fault may occur between windings of the transformer. These faults, known as turn-to-turn faults, are difficult to detect electrically at the terminals of the transformer until they have grown to the point of damaging the transformer beyond repair.
Current differential transformer protection is a simple, reliable, and cost effect method of detecting turn-to-turn faults. This method of protection is only able to detect faults involving 10% of the windings or more. The sensitivity of current differential protection is limited as not to cause false tripping due to normal imbalances in current. Such imbalances in current may occur when a tapchanger is used to increase or decrease the voltage on one side of the transformer.
Digital current differential relays, which monitor tap changer position, compensate for current imbalances due to tapchanger operation. Other causes of current imbalance include current transformer saturation, magnetizing inrush current, and over-excitation. A transformer is designed to operate continuously at 10% above its rated voltage. In this overexcited state, a current imbalance appears which causes a differential current to be sensed by the current differential relay. This limits the current differential relay's sensitivity as it must be designed to ignore current imbalances due to the aforementioned causes.
The current differential transformer protection algorithm, which only makes use of the current magnitude, is based on the principles of an electromechanical relay. Digital relays are capable of computing the negative sequence current on both primary and secondary sides of the transformer along with the phase difference between these two negative sequence currents. By using both phase and magnitude information, negative sequence current could be used to detect turn-to-turn faults involving 3% of the transformer's windings or more.
Turn-to-turn faults may still occur even if no current is flowing on one side of the transformer, such as during energization. With no current flowing in the secondary windings of the transformer, negative sequence current based algorithms become insensitive. A transformer is particularly likely to experience a turn-to-turn fault during this time due to the stresses of energization. This thesis introduces a relay prototype, using both negative sequence current and negative sequence voltage, which retains its sensitivity during energization.
This prototype was constructed using a micro-controller and an analog-to-digital conversion board. The transformer protection relay algorithm, including all hardware interface code and signal processing…
Advisors/Committee Members: Gokaraju, Ramakrishna, Teng, Daniel, Karki, Rajesh, Boulfiza, Mohamed.
Subjects/Keywords: Transformer; Turn-to-Turn Fault; Negative Sequence Voltage; Negative Sequence Current
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APA (6th Edition):
Zacharias, D. (2013). Hardware-in-the-Loop Prototype of a Negative Sequence Based Scheme for Turn-to-Turn Fault Detection in Transformers. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2013-12-1347
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zacharias, Daniel. “Hardware-in-the-Loop Prototype of a Negative Sequence Based Scheme for Turn-to-Turn Fault Detection in Transformers.” 2013. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2013-12-1347.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zacharias, Daniel. “Hardware-in-the-Loop Prototype of a Negative Sequence Based Scheme for Turn-to-Turn Fault Detection in Transformers.” 2013. Web. 27 Feb 2021.
Vancouver:
Zacharias D. Hardware-in-the-Loop Prototype of a Negative Sequence Based Scheme for Turn-to-Turn Fault Detection in Transformers. [Internet] [Thesis]. University of Saskatchewan; 2013. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2013-12-1347.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zacharias D. Hardware-in-the-Loop Prototype of a Negative Sequence Based Scheme for Turn-to-Turn Fault Detection in Transformers. [Thesis]. University of Saskatchewan; 2013. Available from: http://hdl.handle.net/10388/ETD-2013-12-1347
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
6.
Khan, Alimul H 1985-.
ALIMUL KHAN 2018 DESIGN OF AN OPTICAL SENSOR TO DETECT HUMAN INTESTINAL BLEEDING FOR CAPSULE ENDOSCOPY.
Degree: 2018, University of Saskatchewan
URL: http://hdl.handle.net/10388/8607
► Gastrointestinal (GI) bleeding in human is not uncommon that may sometime lead to fatal consequences. Types of GI bleeding include acute and chronic bleeding, upper…
(more)
▼ Gastrointestinal (GI) bleeding in human is not uncommon that may sometime lead to fatal consequences. Types of GI bleeding include acute and chronic bleeding, upper and lower bleeding. In some cases, the patient requires immediate diagnosis. These abnormalities could be detected by using a flexible wired endoscope, a tool to see inside view of the GI tract. An advanced version of endoscopy tool is the wireless capsule endoscopy (WCE), first used in 2001, where the patient swallows an electronic capsule-shaped device which captures thousands of images and sends to an external data recorder via wireless communication. The images are later analyzed by physicians to detect GI abnormalities. The screening process is time-consuming. Delay in bleeding detection may increase the risk of the patient. Therefore, an easy and faster way to detect bleeding in the GI tract by using optical sensors is warranted.
Standard methods to diagnose GI bleeding are still limited due to unpredictable bleeding behaviours, such as the rate of bleeding and the concentration of blood. In addition, proper instrumentation, lack of easy access and control of the sensors are also limiting the techniques of bleeding detection. Blood can be identified by analyzing its optical properties. To determine its optical properties, three types of experiments using a spectrophotometer, a pulse oximeter, and an RGB colour sensor were conducted in this research. The principle is to emit light of a specific spectrum from a source on a liquid sample. Depending on the protein (like hemoglobin) or other substances present in the liquid, a different wavelength of light will be reflected and/or transmitted, which is then detected using a sensor (typically the photodiode).
The objective of this study is to distinguish blood samples (BS) from non-blood samples (NBS) using their optical properties. Different concentrations of horse blood, swine blood, and bovine hemoglobin solutions were used in this experiment as BS. Many other solutions like coffee, tea, juice, coloured water, etc. were used as NBS. One set of data samples was first used to develop the algorithm. Next, another set of samples was used to validate it.
Several optimum light spectrum wavelength were identified. Analysis of the experimental results suggests that it is possible to separate BS from NBS using the optical properties of the substances. The outcomes of this study can be used to implement small optical sensors in a capsule endoscopy system to detect GI bleeding. The optical sensor will eliminate the post-processing of the images and thus save a significant amount of time.
Advisors/Committee Members: Wahid, Khan A, Dinh, Anh V, Chowdhury, Nurul A, Boulfiza, Mohamed.
Subjects/Keywords: bleeding detection; bleeding sensor; IR and Red light; RGB colour sensor; Spectrophotometer
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APA ·
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APA (6th Edition):
Khan, A. H. 1. (2018). ALIMUL KHAN 2018 DESIGN OF AN OPTICAL SENSOR TO DETECT HUMAN INTESTINAL BLEEDING FOR CAPSULE ENDOSCOPY. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/8607
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Khan, Alimul H 1985-. “ALIMUL KHAN 2018 DESIGN OF AN OPTICAL SENSOR TO DETECT HUMAN INTESTINAL BLEEDING FOR CAPSULE ENDOSCOPY.” 2018. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/8607.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Khan, Alimul H 1985-. “ALIMUL KHAN 2018 DESIGN OF AN OPTICAL SENSOR TO DETECT HUMAN INTESTINAL BLEEDING FOR CAPSULE ENDOSCOPY.” 2018. Web. 27 Feb 2021.
Vancouver:
Khan AH1. ALIMUL KHAN 2018 DESIGN OF AN OPTICAL SENSOR TO DETECT HUMAN INTESTINAL BLEEDING FOR CAPSULE ENDOSCOPY. [Internet] [Thesis]. University of Saskatchewan; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/8607.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Khan AH1. ALIMUL KHAN 2018 DESIGN OF AN OPTICAL SENSOR TO DETECT HUMAN INTESTINAL BLEEDING FOR CAPSULE ENDOSCOPY. [Thesis]. University of Saskatchewan; 2018. Available from: http://hdl.handle.net/10388/8607
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
7.
Amanie, James.
Effect of Submerged Arc Welding Parameters on the Microstructure of SA516 and A709 Steel Welds.
Degree: 2011, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2011-07-42
► The effects of submerged arc welding (SAW) current and speed on the microstructures of SA516 grade 70 and A709 grade 50 steel welds were studied…
(more)
▼ The effects of submerged arc welding (SAW) current and speed on the microstructures of SA516 grade 70 and A709 grade 50 steel welds were studied in this research. Steel plates 17 mm-thick were submerged arc welded using different welding currents (from 700 to 850 A) and welding speeds (from 5.3 to 15.3 mm/s). The effect of heat input on the weld metal chemistry, morphologies and chemistry of inclusions and nucleation of acicular ferrite (AF), grain boundary ferrite (GBF) and Widmanstatten ferrite (WF) were evaluated. Optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) microanalysis and transmission electron microscopy (TEM) were used to examine the microstructures of the developed weld joints. PAX-it image analysis software program was utilized for quantitative analysis of the microstructures.
The results showed that it is difficult to ascribe changes in the microstructure that occurred in the heat affected zone (HAZ) and the weld metal regions to a single welding process parameter. Inclusion analysis revealed two types of inclusions formed in the weld metals for both steels. They are spherical and faceted inclusions. It was also observed that acicular ferrite nucleated only on the spherical inclusions. EDS analysis showed that the two inclusions have different chemical compositions.
The results further showed that the total oxygen content of the weld metals of both steels generally increased with welding current, but decreased with increasing welding speed. The prior austenite grain width decreased with increasing welding speed, but increased with increasing welding current (increased heat input). For both SA516 and A709 steel welds, the proportion of acicular ferrite (AF) in the weld metals increased initially, while those of grain boundary ferrite (GBF) and Widmanstatten ferrite (WF) decreased with increasing welding current when welding current was increased from 700 A to 800 A. With further increase in the welding current above 800 A, less acicular ferrite was produced as both GBF and WF proportions increased. However, welding speed did not affect appreciably the amounts of ferrite products in the weld metals.
Non-linear regression models were developed using welding current and welding speed to predict the ferrites (AF, GBF, WF) that formed in the weld metals of the two steels. The adequacy of the models was checked by using the F-statistics.
Advisors/Committee Members: Yannacopoulos, Spiro, Oguocha, Ikechukwuka, Torvi, David, Odeshi, Akindele, Boulfiza, Mohamed.
Subjects/Keywords: Microstructure; Acicular ferrite;
Grain boundary ferrite; Widmanstatten ferrite.
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APA (6th Edition):
Amanie, J. (2011). Effect of Submerged Arc Welding Parameters on the Microstructure of SA516 and A709 Steel Welds. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2011-07-42
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Amanie, James. “Effect of Submerged Arc Welding Parameters on the Microstructure of SA516 and A709 Steel Welds.” 2011. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2011-07-42.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Amanie, James. “Effect of Submerged Arc Welding Parameters on the Microstructure of SA516 and A709 Steel Welds.” 2011. Web. 27 Feb 2021.
Vancouver:
Amanie J. Effect of Submerged Arc Welding Parameters on the Microstructure of SA516 and A709 Steel Welds. [Internet] [Thesis]. University of Saskatchewan; 2011. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2011-07-42.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Amanie J. Effect of Submerged Arc Welding Parameters on the Microstructure of SA516 and A709 Steel Welds. [Thesis]. University of Saskatchewan; 2011. Available from: http://hdl.handle.net/10388/ETD-2011-07-42
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
8.
Poudyal, Umesh 1982-.
Development Length Criteria for Plain and Ransome Bars.
Degree: 2018, University of Saskatchewan
URL: http://hdl.handle.net/10388/8454
► Historical bars such as plain and Ransome bars were used in reinforced concrete structures until about the mid-1950s in the U.S and Canada. Bond provisions…
(more)
▼ Historical bars such as plain and Ransome bars were used in reinforced concrete structures until about the mid-1950s in the U.S and Canada. Bond provisions for plain and Ransome bars are not included in the current edition of Canadian and American codes. Twenty-two splice specimens reinforced with either plain, Ransome, or deformed bars were therefore tested monotonically under four-point loading as a part of a multi-year experimental investigation to develop bond provisions for plain and Ransome bars. The reinforcement was cast either in the bottom or top position. Load versus deflection behaviour, cracking patterns, and maximum load attained by all specimens are presented. Moment curvature analysis was performed for the specimens to calculate the tensile resistance of the reinforcement at the maximum load level.
Reliability-based provisions for splice and development length were proposed for plain bars from a test database of splice specimens. A comparison of the proposed development length required for plain bars as compared to deformed bars, calculated in accordance with CSA A23.3, suggests that plain bars require fifty percent more development length than deformed bars when cast in the bottom position. However, when reinforcement is cast in the top position, the required development length for plain square and plain round bars is two and three times that for modern deformed bars, respectively.
Similarly, reliability-based provisions for splice length were proposed for Ransome bars. A comparison of the proposed splice length of Ransome bars and that calculated for deformed bars in accordance with CSA A23.3 suggests that the bond capacity of Ransome bars closely matches to that of deformed bars when bars are cast in the bottom position. However, the required splice length for Ransome bars is around 25% more than that for modern deformed bars when cast in the top position.
Advisors/Committee Members: Feldman, Lisa R, Wegner, Leon D, Boulfiza, Mohamed, Alexander, John.
Subjects/Keywords: development length; historical structures; plain bars; Ransome bars; structural evaluation
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APA (6th Edition):
Poudyal, U. 1. (2018). Development Length Criteria for Plain and Ransome Bars. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/8454
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Poudyal, Umesh 1982-. “Development Length Criteria for Plain and Ransome Bars.” 2018. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/8454.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Poudyal, Umesh 1982-. “Development Length Criteria for Plain and Ransome Bars.” 2018. Web. 27 Feb 2021.
Vancouver:
Poudyal U1. Development Length Criteria for Plain and Ransome Bars. [Internet] [Thesis]. University of Saskatchewan; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/8454.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Poudyal U1. Development Length Criteria for Plain and Ransome Bars. [Thesis]. University of Saskatchewan; 2018. Available from: http://hdl.handle.net/10388/8454
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
9.
Sapal, Shailza Singh 1985-.
Effectiveness of a Natural Pozzolanic Material from Southern Saskatchewan for Cement Replacement in Concrete.
Degree: 2018, University of Saskatchewan
URL: http://hdl.handle.net/10388/11256
► Pozzolans are a category of supplementary cementitious materials that can be used as a partial replacement of portland cement in concrete. Aside from their environmental…
(more)
▼ Pozzolans are a category of supplementary cementitious materials that can be used as a partial replacement of portland cement in concrete. Aside from their environmental benefits, some pozzolans have been found to increase the strength, reduce the permeability, and thereby increase the durability of concrete. In this study, a natural pozzolanic material from deposits in Southern
Saskatchewan was evaluated for its effectiveness as a partial replacement of portland cement in the production of concrete. Specimens with replacement amounts of 10%, 20%, and 30% by weight of cement were prepared and tested to measure compressive strength and permeability, along with a reference mix without pozzolan for comparison. The effect of sieving out particle sizes greater than 74 μm was investigated. The results showed that the 10% and 20% replacement amounts slowed down the strength development, but produced long-term compressive strengths at greater than six months that did not differ significantly from that of the reference mix, except when pozzolan particle sizes were not limited to less than 74 μm at the 20% replacement amount. The 30% replacement amount produced concrete that was weaker than the control mix by 16% and 8% at 56 days and one year, respectively, when the particle size was controlled. The permeability of samples prepared with 10% pozzolan was statistically lower than that of the reference mix and was also statistically lower when pozzolan particle sizes were limited to less than 74 μm. The natural pozzolan is therefore considered to be an effective cement replacement material.
Advisors/Committee Members: Wegner, Leon D, Boulfiza, Mohamed, Feldman, Lisa R, Tabil, Lope G.
Subjects/Keywords: Cement replacement material; strength; durability.
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APA (6th Edition):
Sapal, S. S. 1. (2018). Effectiveness of a Natural Pozzolanic Material from Southern Saskatchewan for Cement Replacement in Concrete. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/11256
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sapal, Shailza Singh 1985-. “Effectiveness of a Natural Pozzolanic Material from Southern Saskatchewan for Cement Replacement in Concrete.” 2018. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/11256.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sapal, Shailza Singh 1985-. “Effectiveness of a Natural Pozzolanic Material from Southern Saskatchewan for Cement Replacement in Concrete.” 2018. Web. 27 Feb 2021.
Vancouver:
Sapal SS1. Effectiveness of a Natural Pozzolanic Material from Southern Saskatchewan for Cement Replacement in Concrete. [Internet] [Thesis]. University of Saskatchewan; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/11256.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sapal SS1. Effectiveness of a Natural Pozzolanic Material from Southern Saskatchewan for Cement Replacement in Concrete. [Thesis]. University of Saskatchewan; 2018. Available from: http://hdl.handle.net/10388/11256
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
10.
Song, Zhe 1977-.
HIGH PERFORMANCE AND ULTRA HIGH PERFORMANCE CONCRETE WITH LOCALLY AVAILABLE MATERIALS FROM SASKATCHEWAN.
Degree: 2017, University of Saskatchewan
URL: http://hdl.handle.net/10388/7693
► Reinforced concrete structures exhibit various durability problems, such as the corrosion of reinforcing steel, sulfate attack, etc., when exposed to harsh environments. This type of…
(more)
▼ Reinforced concrete structures exhibit various durability problems, such as the corrosion of reinforcing steel, sulfate attack, etc., when exposed to harsh environments. This type of damage often leads to very serious technical and economic problems, such as a short lifetime of infrastructure and high costs associated with their long term maintenance and repair. High performance concrete (HPC) and ultra-high performance concrete (UHPC) could play key roles in solving or in mitigating these problems.
The main research goal of this thesis was to determine whether it is possible to produce high performance concrete (HPC), very-high performance concrete (VHPC) and ultra-high performance concrete (UHPC) that have unique combinations of strength, freeze-thaw durability and self-placeability at competitive costs using materials locally available in
Saskatchewan.
To develop HPC and VHPC/UHPC, a statistical experimental design was used to perform experimental designs, analyze the fitting models and optimize multiple responses. The procedure was implemented using the Design-Expert Version 9.0 software.
Seven materials were researched in this project to make concrete, namely: water, cement, silica fume, silica flour, fine sand, steel fiber, and superplasticizer (SP). Four different properties were measured, including the compressive strength, splitting tensile strength, air content of hardened concrete and flow cone test.
After analyzing the results of these tests, it was found that the goal of developing a HPC material with the specified properties was achieved (flow cone spread value = 274 mm and, after 28 days, the obtained properties were: compressive strength = 82 MPa, splitting tensile strength = 23 MPa and air content = 6%.). The goal of making VHPC with the specified properties was obtained (flow cone spread value = 274 mm and, after 28 days, the obtained properties were: compressive strength
iv
= 102.4 MPa and splitting tensile strength = 23 MPa) regardless of air content. Nevertheless, the results of the analysis clearly showed that it would be impossible to produce a UHPC with a 28 day compressive strength greater than 150 MPa using the mix ingredients and fabrication processes adopted in this study.
Advisors/Committee Members: Boulfiza, Mohamed, Feldman, Lisa, Wegner, Leon D., Oguocha, Ikechukwuka N..
Subjects/Keywords: HPC; UHPC; RSM
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APA ·
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Manager
APA (6th Edition):
Song, Z. 1. (2017). HIGH PERFORMANCE AND ULTRA HIGH PERFORMANCE CONCRETE WITH LOCALLY AVAILABLE MATERIALS FROM SASKATCHEWAN. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/7693
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Song, Zhe 1977-. “HIGH PERFORMANCE AND ULTRA HIGH PERFORMANCE CONCRETE WITH LOCALLY AVAILABLE MATERIALS FROM SASKATCHEWAN.” 2017. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/7693.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Song, Zhe 1977-. “HIGH PERFORMANCE AND ULTRA HIGH PERFORMANCE CONCRETE WITH LOCALLY AVAILABLE MATERIALS FROM SASKATCHEWAN.” 2017. Web. 27 Feb 2021.
Vancouver:
Song Z1. HIGH PERFORMANCE AND ULTRA HIGH PERFORMANCE CONCRETE WITH LOCALLY AVAILABLE MATERIALS FROM SASKATCHEWAN. [Internet] [Thesis]. University of Saskatchewan; 2017. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/7693.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Song Z1. HIGH PERFORMANCE AND ULTRA HIGH PERFORMANCE CONCRETE WITH LOCALLY AVAILABLE MATERIALS FROM SASKATCHEWAN. [Thesis]. University of Saskatchewan; 2017. Available from: http://hdl.handle.net/10388/7693
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
11.
Pourazizi, Reza.
Microstructure Optimization to Prevent Hydrogen-Induced Cracking of API X70 Pipeline Steels in Sour Environments.
Degree: 2020, University of Saskatchewan
URL: http://hdl.handle.net/10388/13186
► These days, by increasing the demand for oil and gas resources, the failure of pipeline steels has become one of the crucial topics in the…
(more)
▼ These days, by increasing the demand for oil and gas resources, the failure of pipeline steels has become one of the crucial topics in the oil and gas transportation industry. The failure of pipeline steels is divided into two major categories: stress corrosion cracking (SCC) and hydrogen assistant cracking (HAC). Hydrogen-induced cracking (HIC) is the main cause of pipeline steels failure in sour environments, which is categorized as a type of HAC. In this type of failure, hydrogen atoms accumulate in the steel and cause cracking by different mechanisms. The main focus of this thesis is to find the effects of texture and microstructural parameters on HIC nucleation and propagation in steels exposed to sour environments and also the effect of such environment on the mechanical properties of steels with different microstructure and texture.
In this thesis, the electrochemical hydrogen charging experiment was used to introduce HIC in API 5L X70 pipeline steels with four different thermo-mechanical control processing (TMCP) parameters. Using the scanning electron microscope (SEM), HIC cracks at the cross-section of samples were observed. The SEM observations indicate that the sample which had more finish rolling steps and smaller grain size was more susceptible to HIC. However, the specimen with larger grains was more susceptible to hardness increment than the steels with smaller grains. The energy dispersive Spectrometer (EDS) results showed that two types of inclusions, namely calcium sulfide (CaS) and aluminum oxide (Al2O3), were responsible for the nucleation of HIC in all examined API 5L X70 samples in sour environments. Comparing the length and quantity of the cracks in the middle and top layers of all samples, it could be concluded that the middle layer was more susceptible to HIC. The martensite phase accumulated around the HIC crack was recognized as the weakest phase that could resist HIC propagation and the specimen which had more deformed grains was more susceptible to HIC.
The hydrogen permeation (HP) test was used to indicate the type of traps in each sample. My experimental results indicated that there are both reversible and irreversible traps in all samples, but the quantity of reversible traps was higher in the samples with smaller grains. These results showed that the increasing the finish rolling steps and cooling rate made the steel more susceptible to the HIC. However, lower cooling rate, more roughing and less finishing reduction steps led to large grains, which were more resistance to the HIC.
The effect of different testing environments, including sour and acidic environments, on the tensile strength and type of failure of X70 pipeline steels were investigated. The results indicate that the acidic environment does not have any significant effect on the failure type and mechanical properties of the samples while the sour environment causes hydrogen embrittlement, and as a result, a brittle fracture happens. The other result achieved by tensile test is that the middle layer of the pipeline slab…
Advisors/Committee Members: Szpunar, Jerzy A., Boulfiza, Mohamed, Oguocha, Ikechukwuka N., Cree, Duncan.
Subjects/Keywords: Pipeline steel; Hydrogen induced cracking; Corrosion; API X70; Sour environment
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APA (6th Edition):
Pourazizi, R. (2020). Microstructure Optimization to Prevent Hydrogen-Induced Cracking of API X70 Pipeline Steels in Sour Environments. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/13186
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Pourazizi, Reza. “Microstructure Optimization to Prevent Hydrogen-Induced Cracking of API X70 Pipeline Steels in Sour Environments.” 2020. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/13186.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Pourazizi, Reza. “Microstructure Optimization to Prevent Hydrogen-Induced Cracking of API X70 Pipeline Steels in Sour Environments.” 2020. Web. 27 Feb 2021.
Vancouver:
Pourazizi R. Microstructure Optimization to Prevent Hydrogen-Induced Cracking of API X70 Pipeline Steels in Sour Environments. [Internet] [Thesis]. University of Saskatchewan; 2020. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/13186.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Pourazizi R. Microstructure Optimization to Prevent Hydrogen-Induced Cracking of API X70 Pipeline Steels in Sour Environments. [Thesis]. University of Saskatchewan; 2020. Available from: http://hdl.handle.net/10388/13186
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
12.
Hu, Andy 1985-.
DEVELOPMENT OF A KINETIC MODEL FOR STEERABLE CATHETERS FOR MINIMALLY INVASIVE SURGERY.
Degree: 2016, University of Saskatchewan
URL: http://hdl.handle.net/10388/7403
► The steerable catheters have demonstrated many advantages to overcome the limitations of the conventional catheters in the minimally invasive surgery. The motion and force transmission…
(more)
▼ The steerable catheters have demonstrated many advantages to overcome the limitations of the conventional catheters in the minimally invasive surgery. The motion and force transmission from the proximal end to distal tip of the catheter have significant effects to the efficiency and safety of surgery. While the force information between the catheter and the body (e.g., vessel) can be obtained by mounting sensors on the distal tip of the catheter, this would be more intrusive and less reliable than the one without the sensors, which is described in this disseration. In addition, the small diameters of the catheters may also restrict the idea of mounting sensors on the distal tip. The other approach to obtain the force information is to infer it from the information outside the body. This will demand an accurate mathematical model that describes the force and motion relation called kinetic model, and unfortunately, such a kinetic model is not available in the literature.
In this dissertation, a kinetic model for steerable catheters is presented wich captures the following characteristics of the steerable catheter, namely (1) the geometrical non-linear behavior of the catheter in motion, (2) the deformable pathway, (3) the friction between the catheter and the pathyway, and (4) the contact between the catheter and pathway. A non-linear finite element system (SPACAR) was employed to capture these characteristics. A test-bed was built and an experiment was carried out to verify the developed kinetic model.
The following conclusions can be drawn from this dissertation: (1) the developed kinetic model is accurte in comparison with those in literature; (2) the Dahl friction model, the LuGre friction model and the simplified LuGre friction model are able to capture the friction behavior between the catheter and the pathway but the Coulomb friction model fails (as it cannot capture the hysteresis property which has a significant influence on the behavior of the catheter); (3) the developed kinetic model has the potential of being used to optimize the design and operation of steerable catheters with several salient findings that (3a) the maximal contact force between the catheter and the pathway occurs on the tip of the distal part or the connecting part between the distal part and catheter body of the catheter and (3b) the rigidity and length of the distal part are crucial structural parameters that affect the motion and force transmission significantly.
There are several contributions made by this dissertation. In the field of the steerable catheter, biomechanics and bio-instrumentation, the contributions are summarized in the following: (1) the approach to develop the kinetic model of the steerable catheter in a complex work environment is useful to model other similar compliant medical devices, such as endoscope; (2) the kinetic model of the steerable catheter can provide the force information to improve the efficiency and safety of MIS (minimally invastive surgery) and to realize the “doctor-assisted” catheter-based…
Advisors/Committee Members: Zhang, Chris, Luo, Yigang, Chen, Daniel, Boulfiza, Mohamed, Wu, Fangxiang, Gupta, Madan.
Subjects/Keywords: Steerable Catheter; Modeling; Kinetics; Contact; Continuum Manipulator
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APA (6th Edition):
Hu, A. 1. (2016). DEVELOPMENT OF A KINETIC MODEL FOR STEERABLE CATHETERS FOR MINIMALLY INVASIVE SURGERY. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/7403
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Hu, Andy 1985-. “DEVELOPMENT OF A KINETIC MODEL FOR STEERABLE CATHETERS FOR MINIMALLY INVASIVE SURGERY.” 2016. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/7403.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Hu, Andy 1985-. “DEVELOPMENT OF A KINETIC MODEL FOR STEERABLE CATHETERS FOR MINIMALLY INVASIVE SURGERY.” 2016. Web. 27 Feb 2021.
Vancouver:
Hu A1. DEVELOPMENT OF A KINETIC MODEL FOR STEERABLE CATHETERS FOR MINIMALLY INVASIVE SURGERY. [Internet] [Thesis]. University of Saskatchewan; 2016. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/7403.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Hu A1. DEVELOPMENT OF A KINETIC MODEL FOR STEERABLE CATHETERS FOR MINIMALLY INVASIVE SURGERY. [Thesis]. University of Saskatchewan; 2016. Available from: http://hdl.handle.net/10388/7403
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
13.
Bergerman, Martin.
Design of free flowing granular drains for groundwater containment applications.
Degree: 2011, University of Saskatchewan
URL: http://hdl.handle.net/10388/etd-01102011-192840
► Many geoenvironmental applications make use of granular drainage layers. Design guidelines for these drains recommend a granular soil that provides for filtration of the adjacent…
(more)
▼ Many geoenvironmental applications make use of granular drainage layers. Design guidelines for these drains recommend a granular soil that provides for filtration of the adjacent base soil. Filtration criteria have been developed through laboratory studies in which fine soils under a concentrated gradient of water are protected from erosion by a filter soil. The primary objective in these studies has been the geotechnical stability of earth-fill structures, while drainage was a secondary consideration. Granular drainage layers have therefore been constructed using fine sand. The subsequent migration of fine soil into these drains has resulted in significant loss in permeability.
The main research objective was to develop design criteria for granular drains to be used for long term operation in environmental applications. The secondary objective was to investigate the relationships between grain size distribution of drain materials and clogging by fines. This was done through a laboratory study where changes in permeability were measured in granular soils infiltrated with fines. Lastly, the effect of salinity on fines deposition was also investigated. The hypothesis of the current study is that coarser granular drains minimize the impact of clogging and provides a better alternative to traditional drain designs for long term environmental applications.
The laboratory study was performed with three granular drainage soils: a French Drain sand designed using the traditional filter design method, a coarser uniform sand, and a coarser graded sand with approximately 40% gravel sized particles. Three fine soils were used to infiltrate the drainage soils; however, their particle size distributions were not significantly different from one another. The results indicate that the permeability of all three drainage soils could be reduced by approximately one order of magnitude with continuous flow of a high concentration of fines (5 g/L). The permeabilities of the sands were reduced to a lesser extent with a lower concentration of fines. Permeabilities of the graded soils decreased more slowly with a lower concentration of fines, when considering pore volumes of flow. However, the rate of permeability decrease was ultimately influenced by the amount of fines delivered to the sample. A lower concentration of fines did not significantly slow the rate of permeability reduction in the uniform sand. All three sands retained a similar mass of fines (samples were split and fines content measured following each test). Salinity in the pore water did not significantly affect deposition, likely due to the fact that the fines contained a small amount of clay sized particles.
When considering that all three drainage soils became clogged with fines during the tests, the coarse soils maintained a relatively high permeability due to the fact that their pre-test permeabilities were high. This information, along with the results from the literature review, has led to the development of recommended new design criteria for…
Advisors/Committee Members: Haug, Moir D., Boulfiza, Mohamed, Sharma, Jitendrapal S., Barbour, S. L., Fonstad, Terrance A..
Subjects/Keywords: fines deposition; filter permeability; groundwater containment; granular drain; soil drain; granular filter; soil filter; base soil
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APA (6th Edition):
Bergerman, M. (2011). Design of free flowing granular drains for groundwater containment applications. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-01102011-192840
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Bergerman, Martin. “Design of free flowing granular drains for groundwater containment applications.” 2011. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/etd-01102011-192840.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bergerman, Martin. “Design of free flowing granular drains for groundwater containment applications.” 2011. Web. 27 Feb 2021.
Vancouver:
Bergerman M. Design of free flowing granular drains for groundwater containment applications. [Internet] [Thesis]. University of Saskatchewan; 2011. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/etd-01102011-192840.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bergerman M. Design of free flowing granular drains for groundwater containment applications. [Thesis]. University of Saskatchewan; 2011. Available from: http://hdl.handle.net/10388/etd-01102011-192840
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
14.
Tiamiyu, Ahmed Alade 1987-.
Dynamic impact response and corrosion behavior of coarse- and ultrafine-grained AISI 321 austenitic stainless steel.
Degree: 2019, University of Saskatchewan
URL: http://hdl.handle.net/10388/12269
► The excellent corrosion-resistance of metastable AISI 321 austenitic stainless steel makes it a choice material in the fabrication of nuclear and chemical plants, pressure vessels,…
(more)
▼ The excellent corrosion-resistance of metastable AISI 321 austenitic stainless steel makes it a choice material in the fabrication of nuclear and chemical plants, pressure vessels, automobile and aircraft components, etc. However, AISI 321 is characterized by low-yield strength and poor tribological properties that hinder its widespread application. Therefore, it is important to improve its yield-strength to expand its structural applications without compromising its excellent corrosion resistance.
In this study, the effect of grain refinement via cryo-rolling followed by annealing on the strength and corrosion resistance of AISI 321 austenitic stainless steel is investigated. The mechanical behavior of the as-received coarse-grain and refined alloy (fine-grain and ultrafine-grain) were investigated at high (dynamic impact) and low (quasi-static compression) strain rates using the split Hopkinson pressure bar and Instron R5500 mechanical testing machine, respectively. The corrosion resistance of coarse-grained (CG), fine-grained (FG), and ultrafine-grained (UFG) specimens were also investigated using electrochemical methods. Scanning and transmission electron microscopy (SEM, TEM), X-ray diffraction (XRD), and electron-backscattered diffraction (EBSD) were used for the microstructural and textural characterization of various specimens of the alloy before and after plastic deformation.
The optimum thermomechanical process conditions for developing UFG structure in the AISI 321 steel is cryo-rolling to 50 % reduction of plate thickness followed by process annealing at 1023 K (750 ℃) for 600 s (10 minutes). The hardness of the UFG steel specimens is determined to be ~195 % higher than that of the as-received (CG) AISI 321 steel. The developed UFG specimens have strong intensity of ζ-fibre ({110}<uvw>) texture, which is attributed to pseudo-texture memory effect in AISI 321 steel. The mechanism for pseudo-texture memory in AISI 321 steel is proposed.
The yield strength of the UFG AISI 321 steel is ~400 and ~200% higher than those of the CG specimens under both quasi-static and dynamic deformation conditions, respectively. Slip and twinning are the active deformation mechanisms in CG specimens. Both are highly suppressed in the UFG specimens due to spatial restriction effect. During plastic deformation, γ-FCC to martensite (αʹ-BCC) phase transformation occurred, which is more favored in the UFG specimens and at low strain rates. The co-existence of martensitic phase transformation paths with and without an intermediate phase (HCP ɛ-martensite) is confirmed in AISI 321 steel during plastic deformation under both quasi-static and dynamic loading conditions. Irrespective of grain size, Shoji-Nishiyama, Kurdjumov-Sachs and Burgers orientation relationships exist between the γ and ɛ, γ and αʹ, and ɛ and αʹ phases, respectively. Thus, the phase transformation sequence follows both FCC γ → BCC αʹ and FCC γ → HCP ɛ → BCC αʹ path. The stable end-orientation of the austenite phase in compression is [110]||CD texture while that of…
Advisors/Committee Members: Odeshi, Akindele G., Szpunar, Jerzy A, Guo, Huiqing, Oguocha, Ikechukwuka, Yang, Qiaoqin, Boulfiza, Mohamed.
Subjects/Keywords: AISI 321 austenitic stainless steel; Thermomechanical processing; Ultrafine-grained structure; Slip; Twinning; Phase transformation; Split Hopkinson pressure bar; Dynamic shock loading; Quasi-static compression; Adiabatic shear band; Corrosion; Transmission electron microscope; Electron backscattered diffraction; Texture; Texture memory; Strain rate sensitivity; Activation volume
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APA (6th Edition):
Tiamiyu, A. A. 1. (2019). Dynamic impact response and corrosion behavior of coarse- and ultrafine-grained AISI 321 austenitic stainless steel. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12269
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Tiamiyu, Ahmed Alade 1987-. “Dynamic impact response and corrosion behavior of coarse- and ultrafine-grained AISI 321 austenitic stainless steel.” 2019. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/12269.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tiamiyu, Ahmed Alade 1987-. “Dynamic impact response and corrosion behavior of coarse- and ultrafine-grained AISI 321 austenitic stainless steel.” 2019. Web. 27 Feb 2021.
Vancouver:
Tiamiyu AA1. Dynamic impact response and corrosion behavior of coarse- and ultrafine-grained AISI 321 austenitic stainless steel. [Internet] [Thesis]. University of Saskatchewan; 2019. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/12269.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tiamiyu AA1. Dynamic impact response and corrosion behavior of coarse- and ultrafine-grained AISI 321 austenitic stainless steel. [Thesis]. University of Saskatchewan; 2019. Available from: http://hdl.handle.net/10388/12269
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
15.
Elsamahy, Mohamed Salah Kamel.
Impacts of midpoint FACTS controllers on the coordiantion between generator phase backup protection and generator capability limits.
Degree: 2011, University of Saskatchewan
URL: http://hdl.handle.net/10388/etd-07102011-162129
► The thesis reports the results of comprehensive studies carried out to explore the impact of midpoint FACTS Controllers (STATCOM and SVC) on the generator distance…
(more)
▼ The thesis reports the results of comprehensive studies carried out to explore the impact of midpoint FACTS Controllers (STATCOM and SVC) on the generator distance phase backup protection in order to identify important issues that protection engineers need to consider when designing and setting a generator protection system. In addition, practical, feasible and simple solutions to mitigate the adverse impact of midpoint FACTS Controllers on the generator distance phase backup protection are explored.
The results of these studies show that midpoint FACTS Controllers have an adverse effect on the generator distance phase backup protection. This adverse effect, which can be in the form of underreach, overreach or a time delay, varies according to the fault type, fault location and generator loading. Moreover, it has been found that the adverse effect of the midpoint FACTS Controllers extends to affect the coordination between the generator distance phase backup protection and the generator steady-state overexcited capability limit.
The Support Vector Machines classification technique is proposed as a replacement for the existing generator distance phase backup protection relay in order to alleviate potential problems. It has been demonstrated that this technique is a very promising solution, as it is fast, reliable and has a high performance efficiency. This will result in enhancing the coordination between the generator phase backup protection and the generator steady-state overexcited capability limit in the presence of midpoint FACTS Controllers.
The thesis also presents the results of investigations carried out to explore the impact of the generator distance phase backup protection relay on the generator overexcitation thermal capability. The results of these investigations reveal that with the relay settings according to the current standards, the generator is over-protected and the generator distance phase backup protection relay restricts the generator overexcitation thermal capability during system disturbances. This restriction does not allow the supply of the maximum reactive power of the generating unit during such events. The restriction on the generator overexcitation thermal capability caused by the generator distance phase backup protection relay highlights the necessity to revise the relay settings. The proposed solution in this thesis is to reduce the generator distance phase backup protection relay reach in order to provide secure performance during system disturbances.
Advisors/Committee Members: Faried, Sherif O., Nguyen, Ha, Chowdhury, Nurul, El-Serafi, Ahmed M., Boulfiza, Mohamed, Liao, Yuan.
Subjects/Keywords: generator capability limits; midpoint FACTS controllers; generator overexcitation limiters; support vector machines; generator phase backup protection
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APA (6th Edition):
Elsamahy, M. S. K. (2011). Impacts of midpoint FACTS controllers on the coordiantion between generator phase backup protection and generator capability limits. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-07102011-162129
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Elsamahy, Mohamed Salah Kamel. “Impacts of midpoint FACTS controllers on the coordiantion between generator phase backup protection and generator capability limits.” 2011. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/etd-07102011-162129.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Elsamahy, Mohamed Salah Kamel. “Impacts of midpoint FACTS controllers on the coordiantion between generator phase backup protection and generator capability limits.” 2011. Web. 27 Feb 2021.
Vancouver:
Elsamahy MSK. Impacts of midpoint FACTS controllers on the coordiantion between generator phase backup protection and generator capability limits. [Internet] [Thesis]. University of Saskatchewan; 2011. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/etd-07102011-162129.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Elsamahy MSK. Impacts of midpoint FACTS controllers on the coordiantion between generator phase backup protection and generator capability limits. [Thesis]. University of Saskatchewan; 2011. Available from: http://hdl.handle.net/10388/etd-07102011-162129
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
16.
Oladimeji, Dotun J 1989-.
Thermal Conductivity of Nuclear Fuel and its Degradation by Physical and Chemical Burnup.
Degree: 2017, University of Saskatchewan
URL: http://hdl.handle.net/10388/8024
► Nuclear fuel performance during reactor operation has been studied using both atomic scale simulation and experimental procedure in order to investigate how nuclear fission process…
(more)
▼ Nuclear fuel performance during reactor operation has been studied using both atomic scale simulation and experimental procedure in order to investigate how nuclear fission process affects both the physical state and the chemistry of the fuel. Attention has been drawn to the consequences of nuclear exposure after Fukushima nuclear accident, as it relates to the impact of modern reactor design and nuclear fuel performance. With the recognition of the inherent risks associated with pure uranium oxide (UO2) fuel reactors, there is a need to study nuclear fuel with a view to highlighting their susceptibility to reactor accident, hence, developing an accident tolerant fuel. In this work, cerium oxide (CeO2) has been deployed as a surrogate material for UO2 fuel due to their uniquely similar physicochemical behaviors as fuel materials during operations of nuclear reactors. CeO2 is, however, non-radioactive.
The nuclear reactor safety analysis revealed that thermal conductivity is an important property of nuclear fuel because it controls fuel operating temperature and therefore influences its safety. In line with this assertion, two key areas of focus have been identified in this investigation: i) degradation of thermal conductivity by structural and fission products in nuclear fuel and ii) the fuel microstructural evolution due to dissolved fission product. The former has been carried out using molecular dynamics (MD) simulations and analytical models over the full range of temperature of interest while the latter was carried out using both experimental procedure and MD simulations.
MD simulations of the structural and thermal properties of CeO2 as a representative of UO2 fuel were carried out using Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) code. The thermal expansion, thermal conductivity, and oxygen ion diffusion were calculated using classical ionic potential models. During these processes, verification of methods was done to establish the best potential for CeO2. The many-body ionic potential in the Embedded Atom Method (EAM) and two-body force field potentials were used to predict lattice parameters and thermal conductivity.
Nuclear fuel efficiency changes during reactor operation because of irradiation process. Fission products like fission gas bubble, pores, cracks, dissolved and precipitated fission product buildup in the fuel matrix. The effect of physical burnup such as porosity on the thermophysical properties of CeO2 was simulated using a large system with thousands of atoms. Pores were induced on the large CeO2 system by carefully removing an appropriate number of atoms in proper proportion to mimic porosity evolution. Lattice parameter and the thermal conductivity were calculated at a different percentage of porosity for CeO2. This calculation relates the degradation of thermal conductivity with a number of pores and increasing temperature.
In irradiated oxide fuels (UO2 and PuO2), several fission products (FP) are produced and they take various chemical states depending on the…
Advisors/Committee Members: Szpunar, Jerzy, Szpunar, Barbara, Powel, Rob, Koustov, Alexandre, Ghezelbash, Masoud, Boulfiza, Mohamed.
Subjects/Keywords: Nuclear Fuel; Molecular Dynamics; Thermal conductivity
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APA (6th Edition):
Oladimeji, D. J. 1. (2017). Thermal Conductivity of Nuclear Fuel and its Degradation by Physical and Chemical Burnup. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/8024
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Oladimeji, Dotun J 1989-. “Thermal Conductivity of Nuclear Fuel and its Degradation by Physical and Chemical Burnup.” 2017. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/8024.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Oladimeji, Dotun J 1989-. “Thermal Conductivity of Nuclear Fuel and its Degradation by Physical and Chemical Burnup.” 2017. Web. 27 Feb 2021.
Vancouver:
Oladimeji DJ1. Thermal Conductivity of Nuclear Fuel and its Degradation by Physical and Chemical Burnup. [Internet] [Thesis]. University of Saskatchewan; 2017. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/8024.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Oladimeji DJ1. Thermal Conductivity of Nuclear Fuel and its Degradation by Physical and Chemical Burnup. [Thesis]. University of Saskatchewan; 2017. Available from: http://hdl.handle.net/10388/8024
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
17.
Yan, Hongzhong.
Two–Way Relaying Communications with OFDM and BICM/BICM-ID.
Degree: 2016, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2016-04-2540
► Relay-aided communication methods have gained strong interests in academic community and been applied in various wireless communication scenarios. Among different techniques in relay-aided communication system,…
(more)
▼ Relay-aided communication methods have gained strong interests in academic community
and been applied in various wireless communication scenarios. Among different techniques
in relay-aided communication system, two-way relaying communication (TWRC) achieves
the highest spectral efficiency due to its bi-directional transmission capability. Nevertheless,
different from the conventional point-to-point communication system, TWRC suffers from
detection quality degradation caused by the multiple-access interference (MAI). In addition,
because of the propagation characteristics of wireless channels, fading and multipath
dispersion also contribute strongly to detection errors. Therefore, this thesis is mainly concerned
with designing transmission and detection schemes to provide good detection quality
of TWRC while taking into account the negative impacts of fading, multipath dispersion
and multiple-access interference.
First, a TWRC system operating over multipath fading channels is considered and orthogonal
frequency-division multiplexing (OFDM) is adopted to handle the inter-symbol
interference (ISI) caused by the multipath dispersion. In particular, adaptive physical-layer
network coding (PNC) is employed to address the MAI issue. By analyzing the detection
error probability, various adaptive PNC schemes are discussed for using with OFDM and
the scheme achieving the best trade-off among performance, overhead and complexity is
suggested.
In the second part of the thesis, the design of distributed precoding in TWRC using
OFDM under multipath fading channels is studied. The objective is to design a distributed
precoding scheme which can alleviate MAI and achieve multipath diversity to combat fading.
Specifically, three types of errors are introduced when analyzing the error probability in the
multiple access (MA) phase. Through analysis and simulation, the scheme that performs
precoding in both time and frequency domains is demonstrated to achieve the maximum
diversity gains under all types of errors.
Finally, the last part of the thesis examines a communication system incorporating forward
error correction (FEC) codes. Specifically, bit-interleaved code modulation (BICM)
without and with iterative decoding (BICM-ID) are investigated in a TWRC system. Distributed
linear constellation precoding (DLCP) is applied to handle MAI and the design
of DLCP in a TWRC system using BICM/BICM-ID is discussed. Taking into account the
multiple access channel from the terminal nodes to the relay node, decoding based on the
quaternary code representation is introduced. Several error probability bounds are derived
to aid in the design of DLCP. Based on these bounds, optimal parameters of DLCP are
obtained through analysis and computer search. It is also found that, by combining XORbased
network coding with successful iterative decoding, the MAI is eliminated and thus
DLCP is not required in a BICM-ID system.
Advisors/Committee Members: Nguyen, Ha H., Boulfiza, Mohamed, Mehr, Aryan S., Bui, Francis M., Ko, Seok-Bum.
Subjects/Keywords: Two-way relaying; Multiple access; OFDM; BICM; BICM-ID; cooperative; distributed precoding; physical-layer network coding; quaternary decoding
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APA (6th Edition):
Yan, H. (2016). Two–Way Relaying Communications with OFDM and BICM/BICM-ID. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2016-04-2540
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Yan, Hongzhong. “Two–Way Relaying Communications with OFDM and BICM/BICM-ID.” 2016. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2016-04-2540.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Yan, Hongzhong. “Two–Way Relaying Communications with OFDM and BICM/BICM-ID.” 2016. Web. 27 Feb 2021.
Vancouver:
Yan H. Two–Way Relaying Communications with OFDM and BICM/BICM-ID. [Internet] [Thesis]. University of Saskatchewan; 2016. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2016-04-2540.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Yan H. Two–Way Relaying Communications with OFDM and BICM/BICM-ID. [Thesis]. University of Saskatchewan; 2016. Available from: http://hdl.handle.net/10388/ETD-2016-04-2540
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
18.
Meier, Adam Dale Andrew.
Field scale trials of a geosynthetic capillary break.
Degree: 2011, University of Saskatchewan
URL: http://hdl.handle.net/10388/etd-04142011-153338
► This thesis discusses the field testing of a newly-developed product, a geosynthetic capillary break (GCB). The GCB was developed for use in engineered soil covers…
(more)
▼ This thesis discusses the field testing of a newly-developed product, a geosynthetic capillary break (GCB). The GCB was developed for use in engineered soil covers when a cover incorporating a capillary break effect would be desirable, but the coarse-grained material (gravel or sand) is unavailable or uneconomical. Engineered soil covers aim to reduce the amount of acid generated from sulphide bearing waste by limiting the ingress of water and/or oxygen. The GCB is a geosynthetic system that is composed of a finely ground rock flour sandwiched between two nonwoven geotextiles and manufactured as a composite layer by needle punching in a process similar to the used for GCL (geosynthetic clay liner). The goal of the GCB is to recreate the capillary break that is achieved with soil layers using a geosynthetic product that is only a few centimetres thick and that can be rolled up and for transportation,
The GCB concept has been demonstrated in a previous study (Park, 2005) based on laboratory column studies and computer modelling. The goal of this project was to determine the effectiveness of the GCB when applied at field scale. Four 25 square test plots were constructed at the tailings management area (TMA) of the HudBay Minerals Inc.(HudBay) mine site located near Flin Flon, MB. One plot contained 1 m of cover soil over top of the GCB (Plot A), one contained only 1 m of cover soil (Plot B), one contained 0.3 m of cover soil over top the GCB (Plot C), and one consisted of a conventional capillary break system with 1 m of cover soil over lying 0.2 m of sand. All of the plots, along with a control plot with no cover, were instrumented with water content sensors and gas sampling ports to monitor the movement of water and oxygen through the various covers. Matric suction sensors were also installed in Plots A and B to measure the water suction within the covers. A meteorological station was installed to gather climatic data which was used to develop a water balance for each of the plots. The plots were constructed and instrumented in the fall of 2005. Data was collected and analyzed until spring of 2007.
Data from the water content sensors show that the GCB was effective in increasing the water content in the soil portion of the cover system. The suction sensors show that the suction across the GCB drops significantly (40 kPa versus less than 1 kPa) as compared to plots which contain no GCB. Data from the gas concentration sensors show that the plots containing capillary breaks reduce the oxygen flux into the tailings. The plots containing the GCB (Plots A and C) resulted in the lowest flux rates, followed by the sand capillary break (Plot D )and no capillary break (Plot B), respectively. This reduction in oxygen flux will reduce the amount of acid generated from waste, as oxygen is required for the creation of acid mine drainage. Overall the study demonstrated that at field scale that the GCB is effective in limiting the ingress of water and oxygen into the tailings under the observed conditions and…
Advisors/Committee Members: Fleming, Ian, Barbour, S.L., Sharma, Jitendrapal, Reeves, Malcolm, Maule, Charles, Boulfiza, Mohamed.
Subjects/Keywords: capillary break; engineered soil cover; geosynthetic
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Manager
APA (6th Edition):
Meier, A. D. A. (2011). Field scale trials of a geosynthetic capillary break. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/etd-04142011-153338
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Meier, Adam Dale Andrew. “Field scale trials of a geosynthetic capillary break.” 2011. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/etd-04142011-153338.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Meier, Adam Dale Andrew. “Field scale trials of a geosynthetic capillary break.” 2011. Web. 27 Feb 2021.
Vancouver:
Meier ADA. Field scale trials of a geosynthetic capillary break. [Internet] [Thesis]. University of Saskatchewan; 2011. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/etd-04142011-153338.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Meier ADA. Field scale trials of a geosynthetic capillary break. [Thesis]. University of Saskatchewan; 2011. Available from: http://hdl.handle.net/10388/etd-04142011-153338
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
19.
Vogel, Timothy 1991-.
Assessing Design and Funding Methods of Water Infrastructure for Saskatchewan First Nations.
Degree: 2019, University of Saskatchewan
URL: http://hdl.handle.net/10388/11772
► Many water systems on First Nations in Saskatchewan are at risk of not being able to consistently meet water quality guidelines, which negatively impacts human…
(more)
▼ Many water systems on First Nations in
Saskatchewan are at risk of not being able to consistently meet water quality guidelines, which negatively impacts human health. It was the goal of my thesis to assess design and funding methods for water infrastructure projects on First Nations. It was important that this research was informed by community values and priorities gained from discussions with Elders, interviews with water treatment officers, and activities with elementary and high school students.
A scoping review looked for existing literature on water infrastructure projects that involved the community in the design process, termed ‘co-design’. Of 1,551 articles searched, only 13 were found using the search terms (and synonyms): “water”, “co-design”, “Indigenous communities”, “infrastructure”, and “Canada”. A common definition of co-design and clear process is required to trend towards community informed design. Co-design as a process for water infrastructure in Indigenous communities encompasses the cultural, traditional, and spiritual values associated with water from the community’s worldview along with the environmental and technical conditions from an engineering standpoint. The increased involvement for this process requires extra funding, which is difficult in communities that are already restricted by rigid funding frameworks.
Communities prefer a centralized system (piped water) to reduce the likelihood of contamination and water quantity rationing. The preference for a centralized system is prevented by a funding formula that does not provide the higher capital expense of this infrastructure. However, the formula can be expanded beyond capital investment and regular operation and maintenance to include costs associated with human health. The installation of both decentralized and centralized systems were quoted and compared for an example community of 100 homes (500 people). The approximate capital cost of a centralized system and decentralized system were found to be 3,512,000 and 1,365,000, respectively. However, the extra costs associated with the decentralized system were 570,000 per year, which covers the greater capital investment for a centralized system in under 5 years. The provision of safe drinking water for human health justifies a greater capital investment on its own, but the inclusion of other variables in the funding formula suggests that it is economically feasible as well.
Advisors/Committee Members: McPhedran, Kerry, Fonstad, Terry, Bharadwaj, Lalita, Peng, Jian, Boulfiza, Mohamed, Belcher, Ken.
Subjects/Keywords: Drinking water; First Nations
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APA ·
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APA (6th Edition):
Vogel, T. 1. (2019). Assessing Design and Funding Methods of Water Infrastructure for Saskatchewan First Nations. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/11772
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Vogel, Timothy 1991-. “Assessing Design and Funding Methods of Water Infrastructure for Saskatchewan First Nations.” 2019. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/11772.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Vogel, Timothy 1991-. “Assessing Design and Funding Methods of Water Infrastructure for Saskatchewan First Nations.” 2019. Web. 27 Feb 2021.
Vancouver:
Vogel T1. Assessing Design and Funding Methods of Water Infrastructure for Saskatchewan First Nations. [Internet] [Thesis]. University of Saskatchewan; 2019. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/11772.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Vogel T1. Assessing Design and Funding Methods of Water Infrastructure for Saskatchewan First Nations. [Thesis]. University of Saskatchewan; 2019. Available from: http://hdl.handle.net/10388/11772
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
20.
Pham, Tung.
Power Allocation in Wireless Relay Networks.
Degree: 2011, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2011-08-65
► This thesis is mainly concerned with power allocation issues in wireless relay networks where a single or multiple relays assist transmission from a single or…
(more)
▼ This thesis is mainly concerned with power allocation issues in wireless relay networks where a single or multiple relays assist transmission from a single or multiple sources to a destination.
First, a network model with a single source and multiple relays is considered, in which both cases of orthogonal and non – orthogonal relaying are investigated. For the case of orthogonal relaying, two power allocation schemes corresponding to two partial channel state information (CSI) assumptions are proposed. Given the lack of full and perfect CSI, appropriate signal processing at the relays and/or destination is also developed. The performance behavior of the system with power allocation between the source and the relays is also analyzed. For the case of non-orthogonal relaying, it is demonstrated that optimal power allocation is not sufficiently effective. Instead, a relay beamforming scheme is proposed. A comprehensive comparison between the orthogonal relaying with power allocation scheme and the non-orthogonal relaying with beamforming scheme is then carried out, which reveals several interesting conclusions with respect to both error performance and system throughput.
In the second part of the thesis, a network model with multiple sources and a single relay is considered. The transmission model is applicable for uplink channels in cellular mobile systems in which multiple mobile terminals communicate with the base station with the help of a single relay station. Single-carrier frequency division multiple access (SC-FDMA) technique with frequency domain equalization is adopted in order to avoid the amplification of the multiple access interference at the relay. Minimizing the transmit power at the relay and optimizing the fairness among the sources in terms of throughput are the two objectives considered in implementing power allocation schemes. The problems are visualized as water-filling and water-discharging models and two optimal power allocation schemes are proposed, accordingly.
Finally, the last part of the thesis is extended to a network model with multiple sources and multiple relays. The orthogonal multiple access technique is employed in order to avoid multiple access interference. Proposed is a joint optimal beamforming and power allocation scheme in which an alternative optimization technique is applied to deal with the non-convexity of the power allocation problem. Furthermore, recognizing the high complexity and large overhead information exchange when the number of sources and relays increases, a relay selection scheme is proposed. Since each source is supported by at most one relay, the feedback information from the destination to each relay can be significantly reduced. Using an equal power allocation scheme, relay selection is still an NP-hard combinatorial optimization problem. Nevertheless, the proposed sub-optimal scheme yields a comparable performance with a much lower computational complexity and can be well suited for practical systems.
Advisors/Committee Members: Nguyen, Ha H., Dinh, Anh V., Daku, Brian L., Saadat-Mehr, Aryan S., Boulfiza, Mohamed, Schober, Robert.
Subjects/Keywords: Wireless relay networks; power allocation; signal processing; optimization.
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APA (6th Edition):
Pham, T. (2011). Power Allocation in Wireless Relay Networks. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2011-08-65
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Pham, Tung. “Power Allocation in Wireless Relay Networks.” 2011. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2011-08-65.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Pham, Tung. “Power Allocation in Wireless Relay Networks.” 2011. Web. 27 Feb 2021.
Vancouver:
Pham T. Power Allocation in Wireless Relay Networks. [Internet] [Thesis]. University of Saskatchewan; 2011. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2011-08-65.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Pham T. Power Allocation in Wireless Relay Networks. [Thesis]. University of Saskatchewan; 2011. Available from: http://hdl.handle.net/10388/ETD-2011-08-65
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Saskatchewan
21.
Wang, Yufeng.
VIBRATION-BASED DAMAGE DETECTION ON A MULTI-GIRDER BRIDGE SUPERSTRUCTURE.
Degree: 2011, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2011-09-192
► Vibration-based damage detection (VBDD) techniques have been proposed as a potential form of structural health monitoring with which an entire structure can be evaluated simultaneously…
(more)
▼ Vibration-based damage detection (VBDD) techniques have been proposed as a potential form of structural health monitoring with which an entire structure can be evaluated simultaneously using relatively few sensors. Since these methods rely on the identification of small changes in dynamic properties (notably natural frequencies and mode shapes) to infer the existence and the location of damage, reliable estimates of these properties are essential for the successful implementation of VBDD schemes.
The research described in this thesis was primarily focused on an experimental investigation of the application of VBDD on a multi-girder bridge superstructure, with the objectives of identifying the most reliable test procedures, developing VBDD techniques that could be used for identifying the presence of damage, and evaluating the performance of VBDD techniques for such structures. The experimental investigation was supplemented by theoretical analyses and numerical verifications. The structure used for this investigation was a one-third scale model of a slab-on-girder composite bridge superstructure featuring four steel girders supporting a steel-free concrete deck, based on the North Perimeter Red River Bridge in Winnipeg, Manitoba.
The experimental tests were conducted in a well-controlled laboratory environment. Forced dynamic excitation was supplied by means of a feedback-controlled hydraulic shaker. Instrumentation used to measure the dynamic response included a closely-spaced grid of accelerometers mounted on the surface of the deck along the girder lines, as well as electrical-resistance foil strain gauges bonded to the girder webs. Damage cases investigated included damage to the steel girders, to the diaphragm members, to the lateral steel straps, and to the concrete deck.
A damage detection indicator was developed based on mode shapes that had been normalized to enclose an area of unity. The resulting area under the plot of the difference between two independently measured mode shapes was then used as the damage indicator. To demonstrate the features and verify the capability of the newly developed damage indicator in the absence of experimental uncertainties, a finite element model of the bridge superstructure was developed and used to generate theoretical data for the modal properties.
A database of pairs of independently measured mode shapes, in which both mode shapes in the pair were obtained with the structure in an identical condition, was used to ascertain the variability of the area of mode shape change indicator when different test procedures were followed. This allowed the definition of threshold values of the damage indicator for each set of test procedures, corresponding to the 90th or 95th percentile of the probability distribution of the damage indicator. When the damage indicator exceeds this value, the presence of damage can be inferred with a high level of confidence. A total of 28 different test protocols were investigated, which included two different excitation methods…
Advisors/Committee Members: Sparling, Bruce F., Wegner, Leon D., Proulx, Jean, Boulfiza, Mohamed, Feldman, Lisa, Dolovich, Allan T., Mazurek, Kerry A..
Subjects/Keywords: Steel-free bridge deck; Multi-girder bridge superstructure; Vibration testing; Structural health monitoring; Vibration-based damage detection
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APA (6th Edition):
Wang, Y. (2011). VIBRATION-BASED DAMAGE DETECTION ON A MULTI-GIRDER BRIDGE SUPERSTRUCTURE. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2011-09-192
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wang, Yufeng. “VIBRATION-BASED DAMAGE DETECTION ON A MULTI-GIRDER BRIDGE SUPERSTRUCTURE.” 2011. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2011-09-192.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wang, Yufeng. “VIBRATION-BASED DAMAGE DETECTION ON A MULTI-GIRDER BRIDGE SUPERSTRUCTURE.” 2011. Web. 27 Feb 2021.
Vancouver:
Wang Y. VIBRATION-BASED DAMAGE DETECTION ON A MULTI-GIRDER BRIDGE SUPERSTRUCTURE. [Internet] [Thesis]. University of Saskatchewan; 2011. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2011-09-192.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wang Y. VIBRATION-BASED DAMAGE DETECTION ON A MULTI-GIRDER BRIDGE SUPERSTRUCTURE. [Thesis]. University of Saskatchewan; 2011. Available from: http://hdl.handle.net/10388/ETD-2011-09-192
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
22.
Ramadani, Thamer.
Effect of Silica Fume on Moisture Flow and the Advective-Dispersive Transport of Ionic Species in Unsaturated Concrete.
Degree: 2013, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2013-04-977
► Under unsaturated conditions, both moisture flow and the transport of ions strongly depend on the degree of saturation in concrete. In the current literature, most…
(more)
▼ Under unsaturated conditions, both moisture flow and the transport of ions strongly depend on the degree of saturation in concrete. In the current literature, most theories and empirical models describe moisture flow and the transport of ions in concrete based on the assumption that concrete is fully submerged in a liquid phase. This simplistic assumption often leads to a systematic underestimation in the amount of ions, such as chlorides, especially in the case of concrete applications subjected to cyclic wetting and drying conditions. In this study, an experimental program was established to determine the key hydraulic parameters needed for modeling the moisture flow and the transport of ions in five types of concrete mixes under unsaturated conditions.
The required hydraulic parameters of the five concrete mixes include the saturated hydraulic permeability, the moisture retention function, and the dependency of the relative diffusion coefficient on degree of saturation. A centrifuge technique was used to determine the saturated hydraulic permeability of the five concrete mixes. The moisture retention data of all concrete mixes were determined using a vapour equilibrium technique. The moisture retention data were then used to determine the van Genuchten empirical parameters for an analytical characterization of the capillary pressure-degree of water saturation and the relative permeability-degree of saturation relationships. The dependency of the relative diffusion coefficient on the degree of water saturation was characterized for each type of concrete mix indirectly using an electrical resistivity technique. The experimental results of this study were used in different empirical models that have been originally developed for soils to examine whether they could be applied for concrete
The five concrete mixes used in this study were characterized by the usage of a different proportion of dry densified silica fume in each concrete mix. Those mixes were used to determine the effect of silica fume on the experimental and the empirical key hydraulic parameters considered in this study.
Advisors/Committee Members: Boulfiza, Mohamed, Wegner, Leon D., Oguocha, Ikechukwuka N..
Subjects/Keywords: Silica fume; Unsaturtaed
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APA (6th Edition):
Ramadani, T. (2013). Effect of Silica Fume on Moisture Flow and the Advective-Dispersive Transport of Ionic Species in Unsaturated Concrete. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2013-04-977
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ramadani, Thamer. “Effect of Silica Fume on Moisture Flow and the Advective-Dispersive Transport of Ionic Species in Unsaturated Concrete.” 2013. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2013-04-977.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ramadani, Thamer. “Effect of Silica Fume on Moisture Flow and the Advective-Dispersive Transport of Ionic Species in Unsaturated Concrete.” 2013. Web. 27 Feb 2021.
Vancouver:
Ramadani T. Effect of Silica Fume on Moisture Flow and the Advective-Dispersive Transport of Ionic Species in Unsaturated Concrete. [Internet] [Thesis]. University of Saskatchewan; 2013. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2013-04-977.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ramadani T. Effect of Silica Fume on Moisture Flow and the Advective-Dispersive Transport of Ionic Species in Unsaturated Concrete. [Thesis]. University of Saskatchewan; 2013. Available from: http://hdl.handle.net/10388/ETD-2013-04-977
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
23.
Ghasemi, Pooya 1985-.
PREPARATION OF RAW AND TREATED FLAX STRAW SORBENT FOR OIL SPILL CLEANUP.
Degree: 2018, University of Saskatchewan
URL: http://hdl.handle.net/10388/11541
► Oil spill incidents occur around the globe and recovering spilled oil from water or soil has become an important subject. One of the significant methods…
(more)
▼ Oil spill incidents occur around the globe and recovering spilled oil from water or soil has become an important subject. One of the significant methods of oil spill cleanup is known as sorption. Most sorbents are made from synthetic materials. Replacing them with a natural and bio friendly material is a sustainable practice. Flax is grown in Canada and specifically in
Saskatchewan. In this study, the possibility of developing a natural sorbent from a by-product of linseed oil production is investigated.
Two flax based sorption materials were chemically analyzed: as-received flax straw and processed flax fibers. Various sections of the straw and fiber were observed using scanning electron microscopy (SEM) to view the structure of the plant. The flax straw was cut into small particles of different lengths in order to study the effect of particle size on light and heavy oil uptake. The effect of sorbent density on oil sorption was also determined as well as the effect of shive and fiber. One of the main hinderance to utilizing natural sorbents for oil sorption in aqueous situation is their tendency to adsorb water. To illustrate the behavior of the flax straw in aqueous situations, two experiments were performed on the samples: water uptake and the oil/water selectivity. In order to address the adsorption of water, a chemical acetylation treatment and a proposed novel method for coating sorbents with linseed oil was accessed. Both acetylated and oil coated samples were compared with raw straw to investigate changes in surface morphology, chemical structure, thermal properties, oil sorption and water uptake.
The result of chemical analysis showed the cellulose content of flax fiber was higher than flax straw while its hemicellulose and lignin contents were higher. Based on SEM observations, the major portion of the flax straw stem consisted of a hollow inner tube surrounded by xylem and phloem vascular tubes. The vascular tube area is also known as shives and was considerably porous. Hence, shives may be a promising location for depositing oil in oil sorption projects. Also, it was observed the flax and shives were covered with plant wax, and this wax was mostly removed by the acetylation treatment. In the linseed oil coated samples, the plant wax was covered with a thin layer as well as fiber and shive particles. Fourier-transform infrared (FTIR) spectroscopy revealed changes in the intensity of bands related to -OH groups and acetyl groups which is an indication of a successful acetylation treatment. FTIR results of coated samples showed blockage of hydroxyl functional groups and appearance of C-H functional groups related to the linseed oil backbone. The success of acetylation was also validated by thermal gravimetric analysis (TGA). The acetylated samples were observed to have a lower thermal stability compared to raw samples due to a decrease in the number of hydrogen bonds. The TGA results of coated samples were similar to those of raw samples as the coating agent was physically bonded to the sample surface…
Advisors/Committee Members: Cree, Duncan, Tabil, Lope G., boulfiza, mohamed, Odeshi, Akindele G..
Subjects/Keywords: sorbent; sorption; oil coated; SEM flax; linseed oil; fiber and shive; acetylation of natural fiber
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APA (6th Edition):
Ghasemi, P. 1. (2018). PREPARATION OF RAW AND TREATED FLAX STRAW SORBENT FOR OIL SPILL CLEANUP. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/11541
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ghasemi, Pooya 1985-. “PREPARATION OF RAW AND TREATED FLAX STRAW SORBENT FOR OIL SPILL CLEANUP.” 2018. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/11541.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ghasemi, Pooya 1985-. “PREPARATION OF RAW AND TREATED FLAX STRAW SORBENT FOR OIL SPILL CLEANUP.” 2018. Web. 27 Feb 2021.
Vancouver:
Ghasemi P1. PREPARATION OF RAW AND TREATED FLAX STRAW SORBENT FOR OIL SPILL CLEANUP. [Internet] [Thesis]. University of Saskatchewan; 2018. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/11541.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ghasemi P1. PREPARATION OF RAW AND TREATED FLAX STRAW SORBENT FOR OIL SPILL CLEANUP. [Thesis]. University of Saskatchewan; 2018. Available from: http://hdl.handle.net/10388/11541
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
24.
Owuamanam, Stephen Ifeanyichukwu 1992-.
Fabrication and Characterization of Bio-epoxy Eggshell Composites.
Degree: 2019, University of Saskatchewan
URL: http://hdl.handle.net/10388/12306
► Low cost fillers such as mineral limestone (LS) are added to polymers in an effort to improve their properties. Waste eggshells (ES), a by-product of…
(more)
▼ Low cost fillers such as mineral limestone (LS) are added to polymers in an effort to improve their properties. Waste eggshells (ES), a by-product of the egg breaking plant industry, contain high content of calcium carbonate (CaCO3) but are generally discarded to landfills at a cost to the company. The use of waste ES as an alternative to mineral LS filler added to bio-epoxy resin was investigated in this study.
Untreated and stearic acid (SA) treated ES and LS fillers (5, 10 and 20 wt. %) were used in fabricating bio-epoxy composite materials via a solution mixing method. Chemical analysis of the filler materials, microstructural examination, physical and mechanical properties of the fabricated composites were evaluated.
The particle density of ES was found to be smaller than that of LS particles. The average particle size was 21.2 ± 2.0 µm, 11.5 ± 1.0 µm, 25.1 ± 2.2 µm and 12.8 ± 2.2 µm for ES, SA treated ES, LS and SA treated LS, respectively. SEM images showed untreated ES and LS particles varied in shape possibly due to grinding during processing. Both untreated and SA treated fillers had rhombohedral-like morphology. Pores were observed in ES due to its characteristic structure compared to the LS particles, which had no visible pores. Fractured surfaces of the composites showed flat and cleavage features for unfilled bio-epoxy composites compared to filled composites which showed jagged surfaces. The density of the composites increased with increase in filler loading for all filler types. Similarly, the void content and water absorption increased with increase in filler loading with 20 wt. % ES composites having the highest values. XRD analysis indicated the presence of calcite, while ICP-MS showed 88 wt. % ± 0.7 CaCO3 in ES, slightly less than the mineral LS as a result of the residual organic membranes still attached. The tensile strength, flexural strength and Charpy impact toughness of the composites reduced with increase in filler loading. However, the flexural modulus improved with increasing filler loading and was maximum at a filler content of 20 wt. % for all filler types. The Charpy impact energy of unfilled bio-epoxy at – 40 °C dropped appreciably to about 58 % of its room temperature value. Economic analysis showed that ~ 18,117,000 kg of CaCO3 can be recovered from waste ES annually in Canada for various applications and can serve as potential replacement of about 1.00 % of mined mineral LS. This research presents promising results for the use of ES as an alternative to LS in bio-epoxy composites for selected applications such as laminating surfboards and skateboards.
Advisors/Committee Members: Cree, Duncan, Odeshi, Akindele G, Oguocha, Ikechukwuka N, Boulfiza, Mohamed.
Subjects/Keywords: Bio-epoxy; Eggshell; Limestone; Calcium Carbonate; Stearic acid; Composite
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APA (6th Edition):
Owuamanam, S. I. 1. (2019). Fabrication and Characterization of Bio-epoxy Eggshell Composites. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12306
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Owuamanam, Stephen Ifeanyichukwu 1992-. “Fabrication and Characterization of Bio-epoxy Eggshell Composites.” 2019. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/12306.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Owuamanam, Stephen Ifeanyichukwu 1992-. “Fabrication and Characterization of Bio-epoxy Eggshell Composites.” 2019. Web. 27 Feb 2021.
Vancouver:
Owuamanam SI1. Fabrication and Characterization of Bio-epoxy Eggshell Composites. [Internet] [Thesis]. University of Saskatchewan; 2019. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/12306.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Owuamanam SI1. Fabrication and Characterization of Bio-epoxy Eggshell Composites. [Thesis]. University of Saskatchewan; 2019. Available from: http://hdl.handle.net/10388/12306
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
25.
Golakiya, Gaurang 1994-.
EXTRACTION OF CALCIUM CARBONATE FROM WASTE EGGSHELLS AS FILLERS IN COMPOSITES.
Degree: 2020, University of Saskatchewan
URL: http://hdl.handle.net/10388/12568
► Large amounts of eggs are consumed in different forms around the world, which results in a massive amount of eggshells. These eggshells can end up…
(more)
▼ Large amounts of eggs are consumed in different forms around the world, which results in a
massive amount of eggshells. These eggshells can end up in landfills, rivers or coastal waters
which can impact public health, contamination of water resources and pollute the environment.
Furthermore, in recent years, special focus is given to industrial sectors that are sources of pollution
to the environment.
Mineral limestone, which is made of calcium carbonate (CaCO3) is used as filler materials for
polymer composites to reduce the cost and improve certain properties. On the other hand, eggshells
contain high amounts of CaCO3 with some organic membranes but are generally considered as a
waste. In this study, to utilize waste eggshell as an alternative to limestone, thermal and chemical
treatments are investigated to produce purified eggshell powder.
Polymer composites were made using bio-epoxy resin with different amounts of eggshell, purified
eggshell and limestone fillers (5, 10 and 20 wt. %). Trace analysis of fillers, microscopic
morphology, thermal and mechanical properties of fabricated composites are evaluated.
The filler powders were sieved using 20 and 32 μm size standard sieves. The particle size analysis
using ImageJ software showed average particle diameters of 11.2 and 23.8 μm for 20 and 32 μm
sieved powders, respectively possibly due to the presence of some lower particle sizes as a result
of grinding. Eggshell powder had a higher weight loss when heated to 850 °C for 2 h than pure
limestone powder due to the removal of organic membranes. Eggshell powder had a lower density
than purified eggshell and limestone particles due to the presence of low density membrane.
Composites with eggshell fillers absorbed higher water than composites with purified eggshell and
limestone filler due to the presence of organic membrane in eggshell. Inductively coupled plasma
mass spectrometry (ICP-MS) analysis showed 87.5 ± 0.5 wt. % of CaCO3 content in pure eggshell,
which increased to 95.0 ± 0.5 wt. % in purified eggshell due to the absence of organic membrane
as a result of thermal and chemical treatments. Scanning electron microscopic (SEM) analysis of
fractured surfaces showed a flat and mirror-like surface for bio-epoxy, which became rougher
when loaded with eggshell fillers. Tensile, flexural and Charpy impact strengths decreased as the
filler content was increased for all fillers. However, tensile and flexural modulus improved
significantly and showed maximum values at 20 wt. % for all three fillers. Thermogravimetric analysis (TGA) analysis showed higher weight losses between 300-550 °C for eggshell powder
than purified eggshell and limestone due to the decomposition of the organic membranes.
Economic analysis for an egg breaking plant in Lethbridge, Alberta showed that approximately
705,000 kg of CaCO3 could be produced annually by recycling waste eggshell.
This research not only presents a way to reduce waste eggshell, but also shows a method to purify
them for use as bio-epoxy composite filler materials. Bio-epoxy…
Advisors/Committee Members: Cree, Duncan, Odeshi, Akindele, Alam, Shafiq, Boulfiza, Mohamed.
Subjects/Keywords: Epoxy composit; Eggshell purification; CaCO3; characterization
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APA ·
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Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Golakiya, G. 1. (2020). EXTRACTION OF CALCIUM CARBONATE FROM WASTE EGGSHELLS AS FILLERS IN COMPOSITES. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12568
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Golakiya, Gaurang 1994-. “EXTRACTION OF CALCIUM CARBONATE FROM WASTE EGGSHELLS AS FILLERS IN COMPOSITES.” 2020. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/12568.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Golakiya, Gaurang 1994-. “EXTRACTION OF CALCIUM CARBONATE FROM WASTE EGGSHELLS AS FILLERS IN COMPOSITES.” 2020. Web. 27 Feb 2021.
Vancouver:
Golakiya G1. EXTRACTION OF CALCIUM CARBONATE FROM WASTE EGGSHELLS AS FILLERS IN COMPOSITES. [Internet] [Thesis]. University of Saskatchewan; 2020. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/12568.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Golakiya G1. EXTRACTION OF CALCIUM CARBONATE FROM WASTE EGGSHELLS AS FILLERS IN COMPOSITES. [Thesis]. University of Saskatchewan; 2020. Available from: http://hdl.handle.net/10388/12568
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
26.
Tolouei Asbforoushani, Maryam.
Corrosion of Carbon Steel Under Disbonded Coatings in Acidified Leaching Processes.
Degree: 2015, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2015-05-2060
► In this research, corrosion behaviour of A36 carbon steel under engineered disbonded coating was investigated in sulphuric acid solutions containing sodium chloride and iron (III)…
(more)
▼ In this research, corrosion behaviour of A36 carbon steel under engineered disbonded coating was investigated in sulphuric acid solutions containing sodium chloride and iron (III) sulphate. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) analyses were carried out to study the morphology and phase composition of corrosion products formed on the carbon steel surface. The results of the SEM analysis showed that only general and pitting corrosion occurred on the carbon steel surface with the engineered crevice. The size of the pits increased as the sulphuric acid and sodium chloride concentrations increased. Moreover, the corrosion products had an open, irregular and loose structure at the pits mouth. The loose and open structure of the corrosion products facilitates diffusion of chloride ions, oxygen, water and contaminants into the carbon steel surface. In contrast, the corrosion products had a very compact and continuous structure outside the pits which provided a good protection against further corrosion.
The x-ray diffraction analysis showed that the corrosion products layer mainly consisted of lepidocrocite (γ-FeOOH), goethite (α-FeOOH) and iron sulphide (FeS) on the crevice edges. The Pourbaix diagram of iron in sulphuric acid solution at room temperature indicates that iron sulphide is formed on the metal surface at different pH values. The akaganeite (β-FeOOH) diffraction peak was not identified in any spectrum which could be due to the low concentration of chloride ions in the solutions. Furthermore, the number of lepidocrocite peaks decreased as the sulphuric acid concentration increased from 10 g l-1 to 50 g l-1. The lepidocrocite is dissolved in the presence of sulphuric acid, and the dissolved ion acts as an oxidant to the metal and hence lower lepidocrocite peaks are identified.
Electrochemical noise measurement (ECN) testing was also performed to investigate the corrosion process occurring on the carbon steel surface with the engineered crevice. The results of the ECN measurements showed that current increased during first few minutes and then decreased slightly. Also, the coupled potential did not change after an initial shift in negative direction. The low current flowing through the carbon steel electrodes and the constant potential showed that the crevice corrosion did not develop. These results imply that the crevice corrosion may not occur on the carbon steel surface in acidic solutions containing chloride ions.
Advisors/Committee Members: Evitts, Richard, Heppner, Kevin, Odeshi, Akindele, Meda, Venkatesh, Boulfiza, Mohamed.
Subjects/Keywords: Corrosion; Carbon Steel; Scanning Electron Microscopy; X-ray Diffraction; Electrochemical Noise Measurement
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APA (6th Edition):
Tolouei Asbforoushani, M. (2015). Corrosion of Carbon Steel Under Disbonded Coatings in Acidified Leaching Processes. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2015-05-2060
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Tolouei Asbforoushani, Maryam. “Corrosion of Carbon Steel Under Disbonded Coatings in Acidified Leaching Processes.” 2015. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2015-05-2060.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tolouei Asbforoushani, Maryam. “Corrosion of Carbon Steel Under Disbonded Coatings in Acidified Leaching Processes.” 2015. Web. 27 Feb 2021.
Vancouver:
Tolouei Asbforoushani M. Corrosion of Carbon Steel Under Disbonded Coatings in Acidified Leaching Processes. [Internet] [Thesis]. University of Saskatchewan; 2015. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2015-05-2060.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tolouei Asbforoushani M. Corrosion of Carbon Steel Under Disbonded Coatings in Acidified Leaching Processes. [Thesis]. University of Saskatchewan; 2015. Available from: http://hdl.handle.net/10388/ETD-2015-05-2060
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
27.
Cheng, Wubin.
Development of A Kinetic Model For Loop-Free Colonoscopy Technology.
Degree: 2013, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2013-09-1060
► The colonoscope is an important tool in diagnosis and management of diseases of the colon. One of the ongoing challenges with this device is that…
(more)
▼ The colonoscope is an important tool in diagnosis and management of diseases of the colon. One of the ongoing challenges with this device is that the colonoscope may form a loop together with the colon during the procedure. The result of the loop is that further insertion of the scope in the colon may not be possible. The loop may also cause risks of perforation of the colon and pain in the patient. There are currently several existing devices to overcome loop formation in colonoscopy, some of which have been introduced in clinical work. However, empirical assessment shows that these devices do not work very well. This is the motivation for the research presented in this thesis.
In this thesis, a new paradigm of thinking, “doctor-assisted colonoscopy,” is proposed to overcome loop formation. In this new approach, the physician’s role is enhanced with new information that is acquired by sensors outside the human body and inferred from the mathematical model. It is referred to as a kinetic model due to the fact that this model describes the kinetic behaviour of the scope. This thesis is devoted to development of this kinetic model. In this study, the model of the colonoscope and the model of the colon are developed based on the Timoshenko beam theory, and parameters in both models are determined by the experiments. The following conclusions then are made: (1) self-locking of the colonoscope is the most basic cause for a loop to occur, while structural instability of the colonsocope is dependent on the self-locking; (2) both the scope and the colon can be well represented with the Timoshenko beam elements and the Linear Complementary Problem (LCP) formulation derived from Signorini’s law, and Coulom’s law for representation of interactions between the colon and scope is adequate; (3) there are effects from the location, looping, and tip deflection of the scope on flexural rigidity of the scope. Approximately, the flexural rigidity of the CF-Q160L colonoscope ranges from 300 to 650 N•cm2, and its accuracy is proven by a good agreement between the model predicted result and experimental result; (4) Rayleigh damping for the CF-Q160L colonoscope depends more on the mass matrix [M] of the colonoscope than the stiffness matrix [K], which is evident by the large coefficient value of “alpha” (0.3864) and the small coefficient value of “beta” (0.0164).
The contributions of this thesis are: (1) the finding that the main cause of the loop is not structural instability of the colonoscope but rather self-locking of the colonoscope, which could lead to design of a “new-generation” colonoscope to avoid the loop; (2) a systematic evaluation of the existing colonoscopy technologies based on the well-proven Axiomatic Design Theory (ADT), which will serve as a guideline for the development of future new colonoscopes in future; (3) an approach to developing a kinetic model of the colonoscope useful to modeling similar objects such as a catheter guide-wire; (4) a novel ex-vivo colonoscopy test-bed with the kinetic and kinematic…
Advisors/Committee Members: Zhang, Wenjun, Johnston, James, Wu, Fangxiang, Boulfiza, Mohamed, Moser, Michael.
Subjects/Keywords: analysis; colonoscope; colon; loop formation; modeling
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APA (6th Edition):
Cheng, W. (2013). Development of A Kinetic Model For Loop-Free Colonoscopy Technology. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2013-09-1060
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Cheng, Wubin. “Development of A Kinetic Model For Loop-Free Colonoscopy Technology.” 2013. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2013-09-1060.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Cheng, Wubin. “Development of A Kinetic Model For Loop-Free Colonoscopy Technology.” 2013. Web. 27 Feb 2021.
Vancouver:
Cheng W. Development of A Kinetic Model For Loop-Free Colonoscopy Technology. [Internet] [Thesis]. University of Saskatchewan; 2013. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2013-09-1060.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Cheng W. Development of A Kinetic Model For Loop-Free Colonoscopy Technology. [Thesis]. University of Saskatchewan; 2013. Available from: http://hdl.handle.net/10388/ETD-2013-09-1060
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
28.
Sanchez Contreras, Denise.
The Effect of Splice Length and Distance between Lapped Reinforcing Bars in Concrete Block Specimens.
Degree: 2014, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2014-04-1529
► The tensile resistance of No. 15 lap spliced reinforcing bars with varying transverse spacing and lap splice length was evaluated in full-scale concrete block wall…
(more)
▼ The tensile resistance of No. 15 lap spliced reinforcing bars with varying transverse spacing and lap splice length was evaluated in full-scale concrete block wall splice specimens. The range of the transverse spacing between bars was limited to that which allowed the bars to remain within the same cell, and included the evaluation of tied spliced bars in contact. Two-and-a-half block wide by three course tall double pullout specimens reinforced with contact lap splices were initially used to determine the range of lap splice length values to be tested in the wall splice specimens such that bond failure of the reinforcement occurred. The double pullout specimens were tested in direct tension with six replicates per arrangement. Three values of lap splice length: 150, 200, and 250 mm, were selected from the testing of the double pullout specimens and tested in the wall splice specimens in combination with three values of transverse spacing: 0, 25, and 50 mm, with three replicates per configuration. A total of twenty-seven two-and-a-half block wide by thirteen course tall wall splice specimens reinforced with two lap splices were tested in four-point loading. Both the double pullout and the wall splice specimens were constructed in running bond with all cells fully grouted.
The tensile resistance of the lap spliced bars in the double pullout specimens was measured directly. The contact lap splices with a 150, 200, and 250 mm lap splice length developed approximately 38, 35 and 29% of the theoretical yield load of the reinforcement, respectively. The difference between the mean tensile resistances of the three reinforcement configurations tested in the double pullout specimens was found to be statistically significant at the 95% confidence level. Different than expected, the tensile resistance of the lap spliced reinforcing bars in the double pullout specimens was inversely proportional to the lap splice length provided. For the short lap splice lengths used in this investigation, the linear but not proportional relationship between bond force and lap splice length known from reinforced concrete is believed to have caused this phenomenon.
An iterative sectional analysis using moment-curvature response was used to calculate the tensile resistance of the lap spliced reinforcement in the wall splice specimens. The calculated mean tensile resistance of the reinforcement increased with increasing lap splice length, and was greater when the bars were in contact. Securing the bars in contact may have influenced the tensile capacity of the contact lap splices as higher stresses are likely to develop as a result of the bar ribs riding over each other with increasing slip. Results of the data analysis suggest that the tensile resistance of non-contact lap splices within the same cell is generally independent of the spacing between the bars. A comparison of the experimental results for the wall splice specimens with the development and splice length provisions in CSA S304.1-04 and TMS 402-11 indicate that both the Canadian and…
Advisors/Committee Members: Feldman, Lisa R., Sparling, Bruce F., Boulfiza, Mohamed.
Subjects/Keywords: Concrete block masonry; Double pullout specimens, Wall splice specimens; Lap splices; Transverse bar spacing; Non-contact lap splices; Bond and development
…masonry construction.
Recent research performed at the University of Saskatchewan included an… …previous research
performed at the University of Saskatchewan (Ahmed and Feldman, 2012)…
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APA ·
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APA (6th Edition):
Sanchez Contreras, D. (2014). The Effect of Splice Length and Distance between Lapped Reinforcing Bars in Concrete Block Specimens. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2014-04-1529
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sanchez Contreras, Denise. “The Effect of Splice Length and Distance between Lapped Reinforcing Bars in Concrete Block Specimens.” 2014. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2014-04-1529.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sanchez Contreras, Denise. “The Effect of Splice Length and Distance between Lapped Reinforcing Bars in Concrete Block Specimens.” 2014. Web. 27 Feb 2021.
Vancouver:
Sanchez Contreras D. The Effect of Splice Length and Distance between Lapped Reinforcing Bars in Concrete Block Specimens. [Internet] [Thesis]. University of Saskatchewan; 2014. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2014-04-1529.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sanchez Contreras D. The Effect of Splice Length and Distance between Lapped Reinforcing Bars in Concrete Block Specimens. [Thesis]. University of Saskatchewan; 2014. Available from: http://hdl.handle.net/10388/ETD-2014-04-1529
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
29.
Bolster, John.
Improved Desiccant Coatings for Heat and Water Vapour Transfer on the Matrix Surfaces of Air-To-Air Regenerative Wheels.
Degree: 2012, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2012-07-539
► Air-to-air energy recovery wheels are now widely used in industry and buildings; however, the effectiveness of water vapor exchange in these regenerative wheels appears to…
(more)
▼ Air-to-air energy recovery wheels are now widely used in industry and buildings; however, the effectiveness of water vapor exchange in these regenerative wheels appears to be much lower than may be economically feasible. The purpose of this research is to investigate the feasibility of using agglomerated desiccant particle coatings to improve the performance of regenerative wheels used in HVAC air-to-air heat and moisture exchange and energy recovery applications. Desiccant particles coated on wheels lose most of their water vapor sorption capacity due to the method of coating.
Desiccant agglomerates can be made by mixing starch, fine silica gel particulate, and water within an agglomerating device. The desiccant particle agglomerating process improves the desiccant mass transfer properties by increasing the overall surface area of desiccant particles; and also by creating a much rougher surface that can increase the likelihood of turbulent flow, and therefore, increasing the overall mass transfer rates.
The industrial desiccant coating process involves submerging the desiccant into a coating agent and then applying this mix to the substrate or the matrix of the energy wheel. This process was improved in this research by ensuring the particles are applied after the coating agent is applied to ensure that the agglomerates or desiccant particles are not submerged by the coating material.
Because testing energy wheels under steady state operating conditions has proved to be difficult, time consuming and costly in the past, a small parallel flow test cell is used to measure the transient response of coated substrate aluminum sheets after a step change in the inlet air humidity or temperature. Using a previously developed theoretical model, the time constants for these inlet step change responses are then used to predict the sensible and latent effectiveness of a regenerative energy wheel coated with the same agglomerated particles, which is rotated at a known operating speed and wheel face velocity. When the new desiccant coatings are used, it is shown that the latent heat effectiveness for a typical wheel could be up to 85%.
It is found that the steady state air flow pressure drop readings for the test cell shows that agglomerated particles coated on the surfaces within the test cell implies some transitional turbulent flow behavior compared to similar substrate surfaces coated in a conventional manner with desiccant particles (e.g. up to 60% higher pressure drop at a channel Reynolds number of 300) in the same test cell. This implied enhanced turbulence flow friction factor in the test cell suggests a somewhat similar enhancement for increased mass and heat transfer coefficients for the test cell or coated wheel matrices.
The transient results for humidity step changes for air flow through the test cell reveals that the adsorption and desorption response time constants are much larger for the agglomerated coated substrate surfaces than the conventional industrial coated surfaces. These data imply much higher…
Advisors/Committee Members: Evitts, Richard W., Besant, Robert W., Tabil, Lope, Phoenix, Aaron, Boulfiza, Mohamed.
Subjects/Keywords: desiccant; coating; agglomeration; silica gel; energy transfer; enthalpy wheel; desiccant wheel; energy wheel; HVAC
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APA (6th Edition):
Bolster, J. (2012). Improved Desiccant Coatings for Heat and Water Vapour Transfer on the Matrix Surfaces of Air-To-Air Regenerative Wheels. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2012-07-539
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Bolster, John. “Improved Desiccant Coatings for Heat and Water Vapour Transfer on the Matrix Surfaces of Air-To-Air Regenerative Wheels.” 2012. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2012-07-539.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bolster, John. “Improved Desiccant Coatings for Heat and Water Vapour Transfer on the Matrix Surfaces of Air-To-Air Regenerative Wheels.” 2012. Web. 27 Feb 2021.
Vancouver:
Bolster J. Improved Desiccant Coatings for Heat and Water Vapour Transfer on the Matrix Surfaces of Air-To-Air Regenerative Wheels. [Internet] [Thesis]. University of Saskatchewan; 2012. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2012-07-539.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bolster J. Improved Desiccant Coatings for Heat and Water Vapour Transfer on the Matrix Surfaces of Air-To-Air Regenerative Wheels. [Thesis]. University of Saskatchewan; 2012. Available from: http://hdl.handle.net/10388/ETD-2012-07-539
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
30.
Armin, Ahad.
Mechanics of soil-blade interaction.
Degree: 2014, University of Saskatchewan
URL: http://hdl.handle.net/10388/ETD-2014-08-1615
► The main objective of this research work is to develop a simulation procedure for modeling the soil-tool interaction for a blade of arbitrary shape. The…
(more)
▼ The main objective of this research work is to develop a simulation procedure for modeling the soil-tool interaction for a blade of arbitrary shape. The primary motivation for this study is developing agricultural robots with limited power and pulling force to help farmers in crop production.
In this thesis, a finite element (FE) investigation of soil-blade interaction is presented. The soil is considered as an elastic-plastic material with the non-associated Drucker-Prager constitutive law. A separation procedure to model the cutting of soil and a method of calculating the forces acting on the blade are proposed and discussed in detail. The procedure uses a separation criterion that becomes active at consecutive nodes on the predefined separation surfaces. In order to mimic soil-blade sliding and soil-soil cutting phenomena contact elements with different properties are applied. To verify correctness of the FE model developed and the procedures used, the FE results are first compared with analytical results available for straight rectangular blades from classical soil mechanics theories; and then the FE results are compared with the experimental ones. Also the effects of blade width, depth and rake angle on blade’s draft force were studied by simulating soil-blade interaction with different blade’s dimensions.
After the analytical and experimental validation of the results for straight rectangular blade, the rectangular curved shape blade was modeled in order to investigate the effects of changing the blade’s radius of curvature on the blade’s draft force.
The soil interaction with straight triangular blade in different rake angles was simulated next. Since the analytical solutions are limited to rectangular blades, calculated draft forces for triangular blade were verified only experimentally. The triangular and rectangular blades with the same width and depth of interaction were also investigated. The results showed that triangular blade draft force is around half of the amount of force acting on the rectangular blade with the same rake angle.
Also the effect of triangular blade’s sharpness and changing the blade’s radius of curvature on draft force was discussed. By changing the blade’s sharpness, the draft forces of triangular blade were calculated in two conditions of constant blade’s width and constant blade’s contact length.
The approach presented in this thesis can be used to investigate the soil-tool interactions for real and more complex blade geometries and soil conditions, and ultimately for improving design of blades to be used in tillage operations.
Advisors/Committee Members: Fotouhi, Reza, Szyszkowski, Walerian, Szpunar, Jerzy A., Johnston, James, Boulfiza, Mohamed.
Subjects/Keywords: finite element analysis; soil-blade contact modeling; blade force
…65
Figure 4.1: The monorail system at the University of Saskatchewan (12 m long and…
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APA ·
Chicago ·
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Export
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APA (6th Edition):
Armin, A. (2014). Mechanics of soil-blade interaction. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/ETD-2014-08-1615
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Armin, Ahad. “Mechanics of soil-blade interaction.” 2014. Thesis, University of Saskatchewan. Accessed February 27, 2021.
http://hdl.handle.net/10388/ETD-2014-08-1615.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Armin, Ahad. “Mechanics of soil-blade interaction.” 2014. Web. 27 Feb 2021.
Vancouver:
Armin A. Mechanics of soil-blade interaction. [Internet] [Thesis]. University of Saskatchewan; 2014. [cited 2021 Feb 27].
Available from: http://hdl.handle.net/10388/ETD-2014-08-1615.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Armin A. Mechanics of soil-blade interaction. [Thesis]. University of Saskatchewan; 2014. Available from: http://hdl.handle.net/10388/ETD-2014-08-1615
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
◁ [1] [2] ▶
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Open Access Theses and Dissertations
