+publisher:"Texas A&M University" +contributor:("Suh, Chii-Der")

Texas A&M University

1. Davis, Joshua Morgan. Characterization of the Bone Loss and Recovery Response at the Distal Femur Metaphysis of the Adult Male Hindlimb Unloaded Rat.

Degree: MS, Mechanical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10630

► Extended periods of mechanical unloading are known to be detrimental to bone health. Astronauts who spend months in microgravity aboard the International Space Station (ISS)… (more)

▼ Extended periods of mechanical unloading are known to be detrimental to bone health. Astronauts who spend months in microgravity aboard the International Space Station (ISS) are at particular risk. It is anticipated that NASA will not drastically increase the size of the astronaut corps, and this will mean increased likelihood of repeat missions for more astronauts. Thus, it is important to better understand the effects that prolonged, multiple bouts of unloading have on bone. This study utilized the hindlimb unloaded (HU) rat model to examine bone loss and recovery for single and double unloading bouts. Adult male Sprague-Dawley rats (6 months old) were randomized into the following groups: baseline (sacrificed at 6 months), 1HU7 (unloaded for 1 month, weight-bearing recovery for 3 months), 2HU10 (unloaded for 1 month, recovered for 2 months, unloaded for another month, and then recovered 2 months), 1HU10 (normal cage activity until 1 month HU ending at month 10, 2 month recovery followed), and aging controls (remained ambulatory throughout experiment). Every month (28 days), animals were terminated and the left femurs were excised, resulting in n=15 per group for each time point. Mineral and geometric properties were measured using peripheral quantitative computed tomography (pQCT) at the distal femur metaphysis, and quasi-static reduced platen compression (RPC) was used to estimate the mechanical properties of cancellous bone. Strength indices based on pQCT parameters were calculated as predictors of mechanical properties. Bone mass properties decreased due to HU and recovered within 2-3 months post-HU. A combination of increased periosteal apposition and endocortical resorption also occurred during HU. The initial HU bout suppressed normal age-related increases in mechanical properties and recovered within 1-2 months. Cancellous compressive strength index (CSI) most closely matched changes in mechanical properties. A second HU bout after two months recovery had a less detrimental effect on pQCT parameters but a greater negative impact on mechanical properties, when compared to pre-HU values. The opposite is true for mechanical properties if loss is characterized relative to aging controls. Recovery after the second HU period did not appear to be significantly affected by a previous bout of HU. Advisors/Committee Members: Hogan, Harry (advisor), Bloomfield, Susan (advisor), Der%22%29&pagesize-30">Suh, Chii-Der (committee member).

Subjects/Keywords: Hindlimb unloading; distal femur; metaphysis; pQCT; bone; cancellous; trabecular; reduced platen compression; RPC; rat; loss; recovery

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APA (6^th Edition):

Davis, J. M. (2012). Characterization of the Bone Loss and Recovery Response at the Distal Femur Metaphysis of the Adult Male Hindlimb Unloaded Rat. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10630

Chicago Manual of Style (16^th Edition):

Davis, Joshua Morgan. “Characterization of the Bone Loss and Recovery Response at the Distal Femur Metaphysis of the Adult Male Hindlimb Unloaded Rat.” 2012. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10630.

MLA Handbook (7^th Edition):

Davis, Joshua Morgan. “Characterization of the Bone Loss and Recovery Response at the Distal Femur Metaphysis of the Adult Male Hindlimb Unloaded Rat.” 2012. Web. 22 Apr 2021.

Vancouver:

Davis JM. Characterization of the Bone Loss and Recovery Response at the Distal Femur Metaphysis of the Adult Male Hindlimb Unloaded Rat. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10630.

Council of Science Editors:

Davis JM. Characterization of the Bone Loss and Recovery Response at the Distal Femur Metaphysis of the Adult Male Hindlimb Unloaded Rat. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10630

Texas A&M University

2. Meenashi Sundaram, Vijay. Direct Nano-Patterning With Nano-Optic Devices.

Degree: MS, Mechanical Engineering, 2011, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7927

► In this study nano-patterning was carried out using two different nano-optic devices namely- the NSOM and Fresnel zone plate. In the first study, NSOM was… (more)

▼ In this study nano-patterning was carried out using two different nano-optic devices namely- the NSOM and Fresnel zone plate. In the first study, NSOM was used to generate nano-patterns on selected semiconducting (Si and Ge) and metallic (Cr, Cu and Ag) targets under different laser pulse durations, laser energies and number of laser pulses. Based on the experimental results, femtosecond laser pulses, provided lower pattern generation thresholds on targets but higher damage thresholds to the NSOM probes at the wavelength (~400-410 nm) studied, compared with nanosecond laser pulses. Three different mechanisms were identified as the dominant processes for pattern generation under different conditions, namely nano-scale laser ablation, nano-scale thermal oxidation and nano-scale melting/recrystallization of the targets. Furthermore, the resulting nano-patterns also showed a significant dependence on the optical properties (i.e., absorption coefficient and surface reflectivity) of the target material. By comparing the obtained experimental results, it was concluded that the optical energy transport from the NSOM probe to the target dominates the pattern generation when femtosecond laser is applied to the NSOM system. When nanosecond laser is applied, both the thermal and optical energy transported from the NSOM probe to the targets attribute to the obtained morphology of nano-patterns on different targets under the experimental conditions studied. In the second study, a traditional Fresnel zone plate with a focus length of 3 micrometres was fabricated with a novel lift-off process in e-beam lithography. The fabrication process involved, using a HSQ/PMMA bi-layer in a negative tone lift-off process with a layer of conducting polyaniline for charge dissipation. HSQ was used as the high resolution negative resist for e-beam patterning and the PMMA under-layer was used to enable a HSQ lift-off process. The fabricated Fresnel zone plate was used to generate nano-patterns on a UV sensitive photoresist using nanosecond laser light with lamda~409nm. The smallest pattern sizes generated was close to the diffraction limit. Nano-pattern sizes generated on the photoresist were comparable with a numerically calculated intensity distribution at the focus spot of the designed Fresnel zone plate obtained from Scalar Diffraction Theory. Advisors/Committee Members: Wen, Sy-Bor (advisor), Der%22%29&pagesize-30">Suh, Chii-Der (committee member), Su, Chin Bing (committee member).

Subjects/Keywords: near field energy transport; nano-crater; nano-protrusion; nano-crystallization; nano laser ablation; nano-oxidation; fresnel zone plate; e-beam lithography; scalar diffraction theory

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APA (6^th Edition):

Meenashi Sundaram, V. (2011). Direct Nano-Patterning With Nano-Optic Devices. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7927

Chicago Manual of Style (16^th Edition):

Meenashi Sundaram, Vijay. “Direct Nano-Patterning With Nano-Optic Devices.” 2011. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7927.

MLA Handbook (7^th Edition):

Meenashi Sundaram, Vijay. “Direct Nano-Patterning With Nano-Optic Devices.” 2011. Web. 22 Apr 2021.

Vancouver:

Meenashi Sundaram V. Direct Nano-Patterning With Nano-Optic Devices. [Internet] [Masters thesis]. Texas A&M University; 2011. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7927.

Council of Science Editors:

Meenashi Sundaram V. Direct Nano-Patterning With Nano-Optic Devices. [Masters Thesis]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7927

Texas A&M University

3. Sekar, Ramnath. Analysis of Remote Diagnosis Architecture for a PLCBbased Automated Assembly System.

Degree: MS, Mechanical Engineering, 2011, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8453

► To troubleshoot equipment installed in geographically distant locations, equipment manufacturers and system integrators are increasingly resorting to remote diagnosis in order to reduce the down… (more)

▼ To troubleshoot equipment installed in geographically distant locations, equipment manufacturers and system integrators are increasingly resorting to remote diagnosis in order to reduce the down time of the equipment, thereby achieving savings in cost and time on both the customer and manufacturer side. Remote diagnosis involves the use of communication technologies to perform fault diagnosis of a system located at a site distant to a troubleshooter. In order to achieve remote diagnosis, several frameworks have been proposed incorporating advancements such as automated fault diagnosis, collaborative diagnosis and mobile communication techniques. Standards exist for the capabilities representative of different levels of remote equipment diagnosis. Several studies have been performed to analyze the ability of human machine interface to assist troubleshooters in local fault diagnosis. However, the ability of a remote diagnosis system architecture to assist the troubleshooter in performing diagnosis and the effects of the failure types and other factors in a remote diagnosis environment on remote troubleshooting performance are not frequently addressed. In this thesis, an attempt is made to understand the factors that affect remote troubleshooting performance: remote diagnosis architecture, nature of failure, skill level of the local operator and level of expertise of the remote troubleshooter. For this purpose, three hierarchical levels of remote diagnosis architectures to diagnose failures in a PLC based automated assembly system were built based on existing standards. Common failures in automated assembly systems were identified and duplicated. Experiments were performed in which expert and novice troubleshooters used these remote diagnosis architectures to diagnose different types of failures while working with novice and engineer operators. The results suggest that in the diagnosis of failures related to measured or monitored system variables by remote expert troubleshooters, remote troubleshooting performance improved with the increase in the levels of the remote diagnosis architectures. In contrast, in the diagnosis of these failures by novice troubleshooters, no significant difference was observed among the three architectures in terms of remote troubleshooting performance and the novice troubleshooters experienced problems with managing the increased information available. Failures unrelated to monitored system parameters resulted in significantly reduced remote troubleshooting performance with all the three architectures in comparison to the failures related to monitored system parameters for both expert and novice troubleshooters. The experts exhibited better information gathering capabilities by spending more time per information source and making fewer transitions between information sources while diagnosing failures. The increase in capabilities of the architectures resulted in reduced operator interaction to a to a greater extent with experts. The difference in terms of overall remote troubleshooting… Advisors/Committee Members: Hsieh, Sheng-Jen (advisor), Der%22%29&pagesize-30">Suh, Chii-Der (committee member), Ji, Jim (committee member).

Subjects/Keywords: remote diagnosis; remote troubleshooting performance; PLC based system

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APA (6^th Edition):

Sekar, R. (2011). Analysis of Remote Diagnosis Architecture for a PLCBbased Automated Assembly System. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8453

Chicago Manual of Style (16^th Edition):

Sekar, Ramnath. “Analysis of Remote Diagnosis Architecture for a PLCBbased Automated Assembly System.” 2011. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8453.

MLA Handbook (7^th Edition):

Sekar, Ramnath. “Analysis of Remote Diagnosis Architecture for a PLCBbased Automated Assembly System.” 2011. Web. 22 Apr 2021.

Vancouver:

Sekar R. Analysis of Remote Diagnosis Architecture for a PLCBbased Automated Assembly System. [Internet] [Masters thesis]. Texas A&M University; 2011. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8453.

Council of Science Editors:

Sekar R. Analysis of Remote Diagnosis Architecture for a PLCBbased Automated Assembly System. [Masters Thesis]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8453

Texas A&M University

4. Gotika, Priyanka. Non-smooth Dynamics Using Differential-algebraic Equations Perspective: Modeling and Numerical Solutions.

Degree: MS, Mechanical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10226

► This thesis addressed non-smooth dynamics of lumped parameter systems, and was restricted to Filippov-type systems. The main objective of this thesis was twofold. Firstly, modeling… (more)

▼ This thesis addressed non-smooth dynamics of lumped parameter systems, and was restricted to Filippov-type systems. The main objective of this thesis was twofold. Firstly, modeling aspects of Filippov-type non-smooth dynamical systems were addressed with an emphasis on the constitutive assumptions and mathematical structure behind these models. Secondly, robust algorithms were presented to obtain numerical solutions for various Filippov-type lumped parameter systems. Governing equations were written using two different mathematical approaches. The first approach was based on differential inclusions and the second approach was based on differential-algebraic equations. The differential inclusions approach is more amenable to mathematical analysis using existing mathematical tools. On the other hand, the approach based on differential-algebraic equations gives more insight into the constitutive assumptions of a chosen model and easier to obtain numerical solutions. Bingham-type models in which the force cannot be expressed in terms of kinematic variables but the kinematic variables can be expressed in terms of force were considered. Further, Coulomb friction was considered in which neither the force can be expressed in terms of kinematic variables nor the kinematic variables in terms of force. However, one can write implicit constitutive equations in terms of kinematic quantities and force. A numerical framework was set up to study such systems and the algorithm was devised. Towards the end, representative dynamical systems of practical significance were considered. The devised algorithm was implemented on these systems and the results were obtained. The results show that the setting offered by differential-algebraic equations is appropriate for studying dynamics of lumped parameter systems under implicit constitutive models. Advisors/Committee Members: Nakshatrala, Kalyana B. (advisor), Reddy, Junuthula N. (committee member), Der%22%29&pagesize-30">Suh, Chii-Der (committee member).

Subjects/Keywords: implicit constitutive models; lumped parameter systems; non-smooth dynamics; differential inclusions; differential-algebraic equations; differential-algebraic inequalities

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APA (6^th Edition):

Gotika, P. (2012). Non-smooth Dynamics Using Differential-algebraic Equations Perspective: Modeling and Numerical Solutions. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10226

Chicago Manual of Style (16^th Edition):

Gotika, Priyanka. “Non-smooth Dynamics Using Differential-algebraic Equations Perspective: Modeling and Numerical Solutions.” 2012. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10226.

MLA Handbook (7^th Edition):

Gotika, Priyanka. “Non-smooth Dynamics Using Differential-algebraic Equations Perspective: Modeling and Numerical Solutions.” 2012. Web. 22 Apr 2021.

Vancouver:

Gotika P. Non-smooth Dynamics Using Differential-algebraic Equations Perspective: Modeling and Numerical Solutions. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10226.

Council of Science Editors:

Gotika P. Non-smooth Dynamics Using Differential-algebraic Equations Perspective: Modeling and Numerical Solutions. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10226

Texas A&M University

5. Velamati, Manasa. Micro Joining of Aluminum Graphite Composites.

Degree: MS, Mechanical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9375

► Advanced aluminum graphite composites have unique thermal properties due to opposing coefficients of thermal expansion of aluminum and graphite. The thermal and mechanical properties of… (more)

Subjects/Keywords: Metal matrix composites; aluminum; graphite; welding; brazing; joining

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APA (6^th Edition):

Velamati, M. (2012). Micro Joining of Aluminum Graphite Composites. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9375

Chicago Manual of Style (16^th Edition):

Velamati, Manasa. “Micro Joining of Aluminum Graphite Composites.” 2012. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9375.

MLA Handbook (7^th Edition):

Velamati, Manasa. “Micro Joining of Aluminum Graphite Composites.” 2012. Web. 22 Apr 2021.

Vancouver:

Velamati M. Micro Joining of Aluminum Graphite Composites. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9375.

Council of Science Editors:

Velamati M. Micro Joining of Aluminum Graphite Composites. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9375

Texas A&M University

6. Barron, Taylor Austin. Experimentation of Composite Repair Techniques for Pipelines Using Finite Element Analysis with Respect to ASME PCC-2, ISO 24817, and Parametric Models.

Degree: MS, Mechanical Engineering, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/157743

► A relatively new method for corrosion repair in steel pipelines has been developed by externally wrapping damaged pipes with composites. Both ASME PCC-2 and ISO… (more)

Subjects/Keywords: composite; finite element analysis; pipeline repair; parametric analysis; analytical modeling

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APA (6^th Edition):

Barron, T. A. (2016). Experimentation of Composite Repair Techniques for Pipelines Using Finite Element Analysis with Respect to ASME PCC-2, ISO 24817, and Parametric Models. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/157743

Chicago Manual of Style (16^th Edition):

Barron, Taylor Austin. “Experimentation of Composite Repair Techniques for Pipelines Using Finite Element Analysis with Respect to ASME PCC-2, ISO 24817, and Parametric Models.” 2016. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/157743.

MLA Handbook (7^th Edition):

Barron, Taylor Austin. “Experimentation of Composite Repair Techniques for Pipelines Using Finite Element Analysis with Respect to ASME PCC-2, ISO 24817, and Parametric Models.” 2016. Web. 22 Apr 2021.

Vancouver:

Barron TA. Experimentation of Composite Repair Techniques for Pipelines Using Finite Element Analysis with Respect to ASME PCC-2, ISO 24817, and Parametric Models. [Internet] [Masters thesis]. Texas A&M University; 2016. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/157743.

Council of Science Editors:

Barron TA. Experimentation of Composite Repair Techniques for Pipelines Using Finite Element Analysis with Respect to ASME PCC-2, ISO 24817, and Parametric Models. [Masters Thesis]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/157743

Texas A&M University

7. Wright, Evan Dalton. Feasibility of Using Nonlinear Time-Frequency Control for Magnetorheological Dampers in Vehicle Suspension.

Degree: MS, Mechanical Engineering, 2017, Texas A&M University

URL: http://hdl.handle.net/1969.1/174890

► Semi-active vehicle suspensions that use magnetorheological (MR) dampers are able to better dissipate vibrations compared to conventional dampers because of their controllable damping characteristics. The… (more)

▼ Semi-active vehicle suspensions that use magnetorheological (MR) dampers are able to better dissipate vibrations compared to conventional dampers because of their controllable damping characteristics. The performance of current MR damper control methods is often hindered by incorrect assumptions and linearized models. Therefore, a need exists to design an adaptive controller with improved accuracy and reliability. The objective of this research is to design an improved controller for MR dampers in vehicle suspension using the nonlinear time-frequency control approach and evaluate its feasibility by numerically employing MATLAB Simulink. Simulations in this research are performed using a simplified quarter car suspension model and modified Bouc-Wen damper model. The proposed control method is evaluated based on its ability to reduce the amplitude of vibrations and minimize acceleration of the car body for various test cases. Simulations are also performed using the skyhook controller and passive suspension to assess the performance of the proposed controller. The results of the simulations show that the proposed nonlinear time-frequency controller can successfully be applied to an MR damper suspensions system for vibration control. The proposed controller outperforms the skyhook controller in terms of reducing acceleration of the car body in each of the tested scenarios. The proposed controller also shows the ability to more efficiently manage the current input to the system. In general, the skyhook controller gives more improved vibration amplitude responses but is prone to generate large spikes in car body acceleration at higher frequency road profile inputs. Simulations performed with the passive system show large displacement amplitudes and inability to prevent oscillation. The feed-forward aspect and adaptive nature of the proposed controller gives it the ability to better compensate for the time-delay in the operation of the MR damper. The proposed controller shows sensitivity to controller parameters when pursuing the best response for different road profile input cases. Advisors/Committee Members: Der%22%29&pagesize-30">Suh, Chii-Der (advisor), Lau, Sai (committee member), Hurlebaus, Stefan (committee member).

Subjects/Keywords: magnetorheological damper; semi-active vibration control

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APA (6^th Edition):

Wright, E. D. (2017). Feasibility of Using Nonlinear Time-Frequency Control for Magnetorheological Dampers in Vehicle Suspension. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174890

Chicago Manual of Style (16^th Edition):

Wright, Evan Dalton. “Feasibility of Using Nonlinear Time-Frequency Control for Magnetorheological Dampers in Vehicle Suspension.” 2017. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/174890.

MLA Handbook (7^th Edition):

Wright, Evan Dalton. “Feasibility of Using Nonlinear Time-Frequency Control for Magnetorheological Dampers in Vehicle Suspension.” 2017. Web. 22 Apr 2021.

Vancouver:

Wright ED. Feasibility of Using Nonlinear Time-Frequency Control for Magnetorheological Dampers in Vehicle Suspension. [Internet] [Masters thesis]. Texas A&M University; 2017. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/174890.

Council of Science Editors:

Wright ED. Feasibility of Using Nonlinear Time-Frequency Control for Magnetorheological Dampers in Vehicle Suspension. [Masters Thesis]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/174890

Texas A&M University

8. Kuo, Chi-Wei 1982-. Guided Wave Propagation in Tubular Section with Multi-Layered Viscoelastic Coating.

Degree: MS, Mechanical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/148398

► Three kinds of propagating waves physically admissible in a tubular section are derived to establish their dispersion characteristics in response to the presence of multi-layered… (more)

Subjects/Keywords: viscoelastic; hollow cylinder; wave propagation

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APA (6^th Edition):

Kuo, C. 1. (2012). Guided Wave Propagation in Tubular Section with Multi-Layered Viscoelastic Coating. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/148398

Chicago Manual of Style (16^th Edition):

Kuo, Chi-Wei 1982-. “Guided Wave Propagation in Tubular Section with Multi-Layered Viscoelastic Coating.” 2012. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/148398.

MLA Handbook (7^th Edition):

Kuo, Chi-Wei 1982-. “Guided Wave Propagation in Tubular Section with Multi-Layered Viscoelastic Coating.” 2012. Web. 22 Apr 2021.

Vancouver:

Kuo C1. Guided Wave Propagation in Tubular Section with Multi-Layered Viscoelastic Coating. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/148398.

Council of Science Editors:

Kuo C1. Guided Wave Propagation in Tubular Section with Multi-Layered Viscoelastic Coating. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/148398

Texas A&M University

9. Berestovskyi, Dmytro V. Surface Finish Modeling in Micromilling of Biocompatible Materials.

Degree: MS, Mechanical Engineering, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/151023

► Over the last few decades, miniaturization of the product became a necessity for many industries to achieve successful technological development, satisfy customer needs, and stay… (more)

▼ Over the last few decades, miniaturization of the product became a necessity for many industries to achieve successful technological development, satisfy customer needs, and stay economically competitive in the market. Thus, many medical, aerospace, and electronic devices tend to decrease in size. Along with the strong demand for miniaturization, new cutting-edge micromanufacturing techniques are developing in order to produce microcomponents with a smooth surface finish and high dimensional accuracy. In the medical industry, some devices require manufacturing of fluidic microchannels on biocompatible materials for transportation of exact amount of medicine to a defined location. Often such microchannels must be manufactured to achieve a high aspect ratio, a submicron surface finish, and an anisotropic controlled profile. The fabrication of such channels on biocompatible materials still poses a challenge. This study developed micromanufacturing technique to produce the microchannels and satisfy all the requirements listed above. Computer controlled micromilling on a high speed machine system in minimum quantity lubrication was used to remove most materials and define a channel pattern. Microchannels were machined with ball end mills of diameters from Ø152μm to Ø198μm on NiTi alloy, 304 and 316L stainless steels. Assessment of microchannel was performed with optical microscopy, scanning electron microscopy, and white light interferometry. The theoretical surface roughness in ball end milling was derived using geometrical approach. The theoretical surface finish model was compared and validated with the experimental surface finish data. Meso- and macro-scale milling confirmed the validity of the model, but surface finish in micro-scale milling was measured to be a few orders of magnitude higher due to size effect and build-up edge. The build-up-edge was reduced when using AlTiN coated tools and milling in minimum quantity lubrication. The empirical surface roughness model obtained in this study shows the dependence of surface finish on chip load in micromilling. In order to further enhance the surface finish of milled microchannels additional finishing technique was identified. A separate study developed an effective electrochemical polishing technique to remove burrs and enhance surface finish of milled microchannels. When applying to 304, 316L stainless steel alloys and NiTi alloy, this hybrid technique can repeatedly produce microchannels with an average surface finish less than 100nm. Advisors/Committee Members: Hung, Wayne Nguyen (advisor), Der%22%29&pagesize-30">Suh, Chii-Der (committee member), Wang, Jyhwen (committee member).

Subjects/Keywords: micromilling; microchannels; surface finish; biocompatible materials

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APA (6^th Edition):

Berestovskyi, D. V. (2013). Surface Finish Modeling in Micromilling of Biocompatible Materials. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/151023

Chicago Manual of Style (16^th Edition):

Berestovskyi, Dmytro V. “Surface Finish Modeling in Micromilling of Biocompatible Materials.” 2013. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/151023.

MLA Handbook (7^th Edition):

Berestovskyi, Dmytro V. “Surface Finish Modeling in Micromilling of Biocompatible Materials.” 2013. Web. 22 Apr 2021.

Vancouver:

Berestovskyi DV. Surface Finish Modeling in Micromilling of Biocompatible Materials. [Internet] [Masters thesis]. Texas A&M University; 2013. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/151023.

Council of Science Editors:

Berestovskyi DV. Surface Finish Modeling in Micromilling of Biocompatible Materials. [Masters Thesis]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/151023

Texas A&M University

10. Wu, Bin. A General Framework for Evolving Network Analysis.

Degree: MS, Mechanical Engineering, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/174585

► Many efforts have been given to model physical systems involving a large number of interacting constituents. Such systems are commonly called complex networks for their… (more)

Subjects/Keywords: Evolving network analysis; Link prediction; Optimization; Wavelet

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APA (6^th Edition):

Wu, B. (2018). A General Framework for Evolving Network Analysis. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174585

Chicago Manual of Style (16^th Edition):

Wu, Bin. “A General Framework for Evolving Network Analysis.” 2018. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/174585.

MLA Handbook (7^th Edition):

Wu, Bin. “A General Framework for Evolving Network Analysis.” 2018. Web. 22 Apr 2021.

Vancouver:

Wu B. A General Framework for Evolving Network Analysis. [Internet] [Masters thesis]. Texas A&M University; 2018. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/174585.

Council of Science Editors:

Wu B. A General Framework for Evolving Network Analysis. [Masters Thesis]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/174585

Texas A&M University

11. Hu, Lingnan. Improved Finite Element Modeling and Dynamic Analysis of Rotating Machinery and a Drillstring with Impact Dampers.

Degree: PhD, Mechanical Engineering, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/174632

► Accurate modeling and analysis approaches have long been important concerns for designers of rotating machinery. This work is focused on the improvement of high-fidelity finite… (more)

▼ Accurate modeling and analysis approaches have long been important concerns for designers of rotating machinery. This work is focused on the improvement of high-fidelity finite element (FE) modeling approaches and software algorithms for analysis of a rotor dynamic system that is comprised of rotors, bearings, and support structures. First, improved formulations for the axisymmetric solid harmonic FE method are developed, which account for the centrifugal stress-stiffening effects and spin-softening effects. A thorough comparison of beam-type FE and axisymmetric solid FE is conducted based on various non-dimensional rotor topologies. In addition to the simulation of rotors, an improved modeling approach is developed to simulate coupled rotor-support systems. This modeling approach utilizes multiple-input and multiple-output (MIMO) transfer functions (TFs) to represent a flexible support structure. The TFs are derived by curve-fitting the frequency response functions of the support model at bearing locations, and then transform into a state-space model to perform general rotor dynamic analyses. Moreover, improvements are made in modeling a rotor system that undergoes large support motion. The shaft continuum is discretized with beam FEs and connected to the support structure via hydrodynamic journal bearings. The bearing forces acting on the rotor are determined by solving the Reynold’s equation for lubricant film pressure utilizing a two-dimensional (2D) FE fluid film model. The influences of the time-varying parameters and unloaded bearings on the dynamic behavior of the rotor system are investigated. This work also contributes to the development of novel centralized impact and torsional dampers for suppression of lateral and torsional stick-slip vibrations of drillstrings. The rotor model of the drillstring utilizes the beam FEs that account for the gravity and axial loading effects on the transverse string stiffness and includes the radial and tangential contact forces that occur when the impactors contact the drill collar or sub. An improved contact force model containing nonlinear Hertzian contact restoring forces and nonlinear, viscous contact damping force is developed, in place of the conventional coefficient of restitution (COR) model that cannot provide the required normal and tangential contact forces. Advisors/Committee Members: Palazzolo, Alan (advisor), Der%22%29&pagesize-30">Suh, Chii-Der (committee member), Hajimirza, Shima (committee member), Hurlebaus, Stefan (committee member).

Subjects/Keywords: Dynamics; Modeling and Analysis; Software Algorithm; Finite Element; Rotor; Impact Damper

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hu, L. (2018). Improved Finite Element Modeling and Dynamic Analysis of Rotating Machinery and a Drillstring with Impact Dampers. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/174632

Chicago Manual of Style (16^th Edition):

Hu, Lingnan. “Improved Finite Element Modeling and Dynamic Analysis of Rotating Machinery and a Drillstring with Impact Dampers.” 2018. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/174632.

MLA Handbook (7^th Edition):

Hu, Lingnan. “Improved Finite Element Modeling and Dynamic Analysis of Rotating Machinery and a Drillstring with Impact Dampers.” 2018. Web. 22 Apr 2021.

Vancouver:

Hu L. Improved Finite Element Modeling and Dynamic Analysis of Rotating Machinery and a Drillstring with Impact Dampers. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/174632.

Council of Science Editors:

Hu L. Improved Finite Element Modeling and Dynamic Analysis of Rotating Machinery and a Drillstring with Impact Dampers. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/174632

Texas A&M University

12. Kim, Sitae. Nonlinear Response and Bifurcations Analysis of Rotor-Fluid Film Bearing Systems.

Degree: PhD, Mechanical Engineering, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/158991

► Nonlinear response, bifurcations and stability of rotor-fluid film bearing systems are studied using various numerical investigation schemes such as autonomous/non-autonomous shooting, arc-length continuation, direct numerical… (more)

▼ Nonlinear response, bifurcations and stability of rotor-fluid film bearing systems are studied using various numerical investigation schemes such as autonomous/non-autonomous shooting, arc-length continuation, direct numerical integrations, Poincaré sections, Lyapunov exponents, etc. Two types of hydrodynamic bearings, a floating ring bearing (FRB) and a tilting pad journal bearing (TPJB), are employed in this study. The nonlinear characteristic of each bearing is analyzed as supports of a rigid rotor system as well as a flexible rotor system. Depending on the existence of the unbalance force on the rotor/disks, autonomous (free vibration) and non-autonomous responses (mass unbalanced excitation) are both identified, and the nonlinear reaction force produced on the lubricant layer is obtained using the finite element method. In addition to isoviscosity lubricants, thermo-hydrodynamic lubricant model is developed to investigate thermal effects on rotordynamic bifurcations; in the procedure, a variable viscosity Reynolds equation and the energy equation are solved simultaneously. For computation efficiency in the analytical bifurcation study, an advanced shooting algorithm, which is combined with the deflation theory and the parallel computing strategy, is proposed for both the autonomous and the non-autonomous cases. In the study with flexible rotors, the finite element based beam models are employed and the model reduction technique such as Component Mode Synthesis is utilized to condense the system degree of freedom. This dissertation consists of four main discussions regarding: 1) nonlinear response and bifurcations of a rigid rotor supported by FRBs; 2) effects of a thermo-hydrodynamic (THD) FRB model on rotordynamic bifurcations; 3) nonlinear response and bifurcations of a rigid rotor supported by TPJBs; 4) extension of study to general, complex, multi-mass rotor beam models. In case 1), multiple coexistent solutions and bifurcation scenarios are identified, and those are depended on the ratio of floating ring length to diameter (L/D). Numerical illustrations regarding jumps between two stable limit cycles and quenching large vibrations are demonstrated, and chaos is investigated with the aid of Lyanpunov exponent. In case 2), the Hopf bifurcation onset is strongly dependent on thermal conditions, and the saddle node bifurcation points are significantly shifted compared to the isothermal model. In addition, the unbalanced responses stability and bifurcation onsets are highly reliant on the lubricant supply temperature. In case 3), loci of bifurcations are identified, and heavily loaded bearings and/or high unbalance force may induce consecutive transference of response in forms of synchronous to sub-synchronous, quasi-periodic responses and chaotic motions. The periodic doubling bifurcations, saddle node bifurcations and corresponding local stability are reliably determined by selections of pad preload, pivot offset, and lubricant viscosity sets. In case 4), two industrial applications such as a turbocharger… Advisors/Committee Members: Palazzolo, Alan B (advisor), Chang, Kuang-An (committee member), Hur, Pilwon (committee member), Der%20Steve%22%29&pagesize-30">Suh, Chii-Der Steve (committee member).

Subjects/Keywords: nonlinear response; bifurcations; chaos; rotor; fluid-film bearings; floating ring bearings; tilt-pad journal bearings; shooting; continuation; deflation; Lyapunov exponents

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APA (6^th Edition):

Kim, S. (2016). Nonlinear Response and Bifurcations Analysis of Rotor-Fluid Film Bearing Systems. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/158991

Chicago Manual of Style (16^th Edition):

Kim, Sitae. “Nonlinear Response and Bifurcations Analysis of Rotor-Fluid Film Bearing Systems.” 2016. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/158991.

MLA Handbook (7^th Edition):

Kim, Sitae. “Nonlinear Response and Bifurcations Analysis of Rotor-Fluid Film Bearing Systems.” 2016. Web. 22 Apr 2021.

Vancouver:

Kim S. Nonlinear Response and Bifurcations Analysis of Rotor-Fluid Film Bearing Systems. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/158991.

Council of Science Editors:

Kim S. Nonlinear Response and Bifurcations Analysis of Rotor-Fluid Film Bearing Systems. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/158991

Texas A&M University

13. Kim, Wooram. Improved Time Integration Algorithms for the Analysis of Structural Dynamics.

Degree: PhD, Mechanical Engineering, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/158031

► In this dissertation one family of second-order and two families of higher-order time integration algorithms are newly developed. For the development of a new family… (more)

▼ In this dissertation one family of second-order and two families of higher-order time integration algorithms are newly developed. For the development of a new family of second-order time integration algorithms, the original equation of structural dynamics is rewritten as two first order differential equations and one algebraic equation. These equations are called mixed formulations, because they include three different kinds of dependent variables (i.e., the displacement, velocity, and acceleration vectors). Equal linear (for the first sub-step) and quadratic (for the second sub-step) Lagrange type interpolation functions in time are used to approximate all three variables involved in the mixed formulations, then the time finite element method and the collocation method are applied to the velocity-displacement and velocity-acceleration relations of the mixed formulations to obtain one- and two-step time integration schemes, respectively. Newly developed one- and two-step time integration schemes are combined as one complete algorithm to achieve enhanced computational features. Two collocation parameters, which are included in the complete algorithm, are optimized and restated in terms of the spectral radius in the high frequency limit (also called the ultimate spectral radius) for the practical control of algorithmic dissipation. Both linear and nonlinear numerical examples are analyzed by using the new algorithm to demonstrate enhanced performance of it. The newly developed second-order algorithm can include the Baig and Bathe method and the non-dissipative case as special cases of its family. For the development of the first family of higher-order time integration algorithms, the displacement vector is approximated over the time interval by using the Hermite interpolation functions in time. The residual vector is defined by substituting the approximated displacement vector into the equation of structural dynamics. The modified weighted residual method is applied to the residual vector. The weight parameters are used to restate the integral forms of the weighted residual statements as algebraic forms, then these parameters are optimized by using the single-degree-of- freedom problem and its exact solution to achieve improved accuracy and unconditional stability. Numerical examples are used to verify performances of the new algorithms. For the development of the second family of implicit higher-order time integration algorithms, the mixed formulations that include three time dependent variables (i.e., the displacement, velocity and acceleration vectors) are used. The equal degree Lagrange type interpolation functions in time are used to approximate the dependent variables involved in the mixed formulations, and the time finite element method and the modified weighted residual method are applied to the velocity-displacement and velocity-acceleration relations of the mixed formulations. Weight parameters are used and optimized to achieve preferable attributes of time integration algorithms. Specially considered… Advisors/Committee Members: Reddy, Junuthula Narasimha (advisor), Talreja, Ramesh (committee member), Der%20Steve%22%29&pagesize-30">Suh, Chii-Der Steve (committee member), Goenezen, Sevan (committee member).

Subjects/Keywords: time integration; structural dynamics; higher-order algorithms; transient analysis; the generalized alpha method; the Baig and Bathe method

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kim, W. (2016). Improved Time Integration Algorithms for the Analysis of Structural Dynamics. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/158031

Chicago Manual of Style (16^th Edition):

Kim, Wooram. “Improved Time Integration Algorithms for the Analysis of Structural Dynamics.” 2016. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/158031.

MLA Handbook (7^th Edition):

Kim, Wooram. “Improved Time Integration Algorithms for the Analysis of Structural Dynamics.” 2016. Web. 22 Apr 2021.

Vancouver:

Kim W. Improved Time Integration Algorithms for the Analysis of Structural Dynamics. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/158031.

Council of Science Editors:

Kim W. Improved Time Integration Algorithms for the Analysis of Structural Dynamics. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/158031

Texas A&M University

14. Wu, Zhenhua. Efficient Detection on Stochastic Faults in PLC Based Automated Assembly Systems With Novel Sensor Deployment and Diagnoser Design.

Degree: PhD, Mechanical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11183

► In this dissertation, we proposed solutions on novel sensor deployment and diagnoser design to efficiently detect stochastic faults in PLC based automated systems First, a… (more)

▼ In this dissertation, we proposed solutions on novel sensor deployment and diagnoser design to efficiently detect stochastic faults in PLC based automated systems First, a fuzzy quantitative graph based sensor deployment was called upon to model cause-effect relationship between faults and sensors. Analytic hierarchy process (AHP) was used to aggregate the heterogeneous properties between sensors and faults into single edge values in fuzzy graph, thus quantitatively determining the fault detectability. An appropriate multiple objective model was set up to minimize fault unobservability and cost while achieving required detectability performance. Lexicographical mixed integer linear programming and greedy search were respectively used to optimize the model, thus assigning the sensors to faults. Second, a diagnoser based on real time fuzzy Petri net (RTFPN) was proposed to detect faults in discrete manufacturing systems. It used the real time PN to model the manufacturing plant while using fuzzy PN to isolate the faults. It has the capability of handling uncertainties and including industry knowledge to diagnose faults. The proposed approach was implemented using Visual Basic, and tested as well as validated on a dual robot arm. Finally, the proposed sensor deployment approach and diagnoser were comprehensively evaluated based on design of experiment techniques. Two-stage statistical analysis including analysis of variance (ANOVA) and least significance difference (LSD) were conducted to evaluate the diagnosis performance including positive detection rate, false alarm, accuracy and detect delay. It illustrated the proposed approaches have better performance on those evaluation metrics. The major contributions of this research include the following aspects: (1) a novel fuzzy quantitative graph based sensor deployment approach handling sensor heterogeneity, and optimizing multiple objectives based on lexicographical integer linear programming and greedy algorithm, respectively. A case study on a five tank system showed that system detectability was improved from the approach of signed directed graph's 0.62 to the proposed approach's 0.70. The other case study on a dual robot arm also show improvement on system's detectability improved from the approach of signed directed graph's 0.61 to the proposed approach's 0.65. (2) A novel real time fuzzy Petri net diagnoser was used to remedy nonsynchronization and integrate useful but incomplete knowledge for diagnosis purpose. The third case study on a dual robot arm shows that the diagnoser can achieve a high detection accuracy of 93% and maximum detection delay of eight steps. (3) The comprehensive evaluation approach can be referenced by other diagnosis systems' design, optimization and evaluation. Advisors/Committee Members: Hsieh, Sheng-jen (advisor), San Andres, Luis (committee member), Langari, Reza (committee member), Der%22%29&pagesize-30">Suh, Chii-Der (committee member), Ding, Yu (committee member).

Subjects/Keywords: Fault Detection; Stochastic Faults; PLC; Automated System; Novel; Sensor Deployment; Diagnoser

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wu, Z. (2012). Efficient Detection on Stochastic Faults in PLC Based Automated Assembly Systems With Novel Sensor Deployment and Diagnoser Design. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11183

Chicago Manual of Style (16^th Edition):

Wu, Zhenhua. “Efficient Detection on Stochastic Faults in PLC Based Automated Assembly Systems With Novel Sensor Deployment and Diagnoser Design.” 2012. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11183.

MLA Handbook (7^th Edition):

Wu, Zhenhua. “Efficient Detection on Stochastic Faults in PLC Based Automated Assembly Systems With Novel Sensor Deployment and Diagnoser Design.” 2012. Web. 22 Apr 2021.

Vancouver:

Wu Z. Efficient Detection on Stochastic Faults in PLC Based Automated Assembly Systems With Novel Sensor Deployment and Diagnoser Design. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11183.

Council of Science Editors:

Wu Z. Efficient Detection on Stochastic Faults in PLC Based Automated Assembly Systems With Novel Sensor Deployment and Diagnoser Design. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11183

Texas A&M University

15. Giron Palomares, Jose. Understanding, Modeling and Predicting Hidden Solder Joint Shape Using Active Thermography.

Degree: PhD, Mechanical Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11223

► Characterizing hidden solder joint shapes is essential for electronics reliability. Active thermography is a methodology to identify hidden defects inside an object by means of… (more)

▼ Characterizing hidden solder joint shapes is essential for electronics reliability. Active thermography is a methodology to identify hidden defects inside an object by means of surface abnormal thermal response after applying a heat flux. This research focused on understanding, modeling, and predicting hidden solder joint shapes. An experimental model based on active thermography was used to understand how the solder joint shapes affect the surface thermal response (grand average cooling rate or GACR) of electronic multi cover PCB assemblies. Next, a numerical model simulated the active thermography technique, investigated technique limitations and extended technique applicability to characterize hidden solder joint shapes. Finally, a prediction model determined the optimum active thermography conditions to achieve an adequate hidden solder joint shape characterization. The experimental model determined that solder joint shape plays a higher role for visible than for hidden solder joints in the GACR; however, a MANOVA analysis proved that hidden solder joint shapes are significantly different when describe by the GACR. An artificial neural networks classifier proved that the distances between experimental solder joint shapes GACR must be larger than 0.12 to achieve 85% of accuracy classifying. The numerical model achieved minimum agreements of 95.27% and 86.64%, with the experimental temperatures and GACRs at the center of the PCB assembly top cover, respectively. The parametric analysis proved that solder joint shape discriminability is directly proportional to heat flux, but inversely proportional to covers number and heating time. In addition, the parametric analysis determined that active thermography is limited to five covers to discriminate among hidden solder joint shapes. A prediction model was developed based on the parametric numerical data to determine the appropriate amount of energy to discriminate among solder joint shapes for up to five covers. The degree of agreement between the prediction model and the experimental model was determined to be within a 90.6% for one and two covers. The prediction model is limited to only three solder joints, but these research principles can be applied to generate more realistic prediction models for large scale electronic assemblies like ball grid array assemblies having as much as 600 solder joints. Advisors/Committee Members: Hsieh, Sheng-Jen (advisor), Alvarado, Jorge (committee member), Han, Je-Chin (committee member), Der%22%29&pagesize-30">Suh, Chii-Der (committee member).

Subjects/Keywords: active thermography; hidden solder joint; FEA; multi PCB assemblies; nondestructive evaluation; parametric analysis; artificial neural networks

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APA (6^th Edition):

Giron Palomares, J. (2012). Understanding, Modeling and Predicting Hidden Solder Joint Shape Using Active Thermography. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11223

Chicago Manual of Style (16^th Edition):

Giron Palomares, Jose. “Understanding, Modeling and Predicting Hidden Solder Joint Shape Using Active Thermography.” 2012. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11223.

MLA Handbook (7^th Edition):

Giron Palomares, Jose. “Understanding, Modeling and Predicting Hidden Solder Joint Shape Using Active Thermography.” 2012. Web. 22 Apr 2021.

Vancouver:

Giron Palomares J. Understanding, Modeling and Predicting Hidden Solder Joint Shape Using Active Thermography. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11223.

Council of Science Editors:

Giron Palomares J. Understanding, Modeling and Predicting Hidden Solder Joint Shape Using Active Thermography. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-11223

Texas A&M University

16. Mijares Tobias, Jorge Arturo. Detection of Lubrication Starvation in Ball Bearings by Means of Lateral and Torsional Vibrations.

Degree: PhD, Mechanical Engineering, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/173315

► Considerable research has been conducted in fault detection and diagnosis for ball bearings but it has been focused on detecting the early stages of imminent… (more)

▼ Considerable research has been conducted in fault detection and diagnosis for ball bearings but it has been focused on detecting the early stages of imminent faults due to fatigue. In reality, most bearings never reach the expected life or fatigue cycles due to problems related to maintenance or installation. This work studies lubrication starvation, which is one of the main causes of premature bearing failure. This work focuses on explaining the origin of the frequency indicators based on proposed bearing models. The validation of one of the models is achieved through a series of experiments measuring lateral vibrations and proving that the characteristic signal originates from the gap created by the absence of lubricant. Additionally, several lateral vibration indicators are compared for fault detection concluding that Fast-Kurtogram is the best technique for detecting lubrication starvation. A further diagnosis using envelope analysis verifies another model that proposes the ball pass frequency of the outer race (BPFO) as the main indicator of lubrication starvation in the frequency domain. An alternative method based on torsional vibrations at the shaft is additionally evaluated. A sensor based on the Time Interval Measurement System (TIMS) is developed using a field programmable gate array (FPGA) and a quadrature encoder to measure torsional vibrations. From the simulation of torque friction, the torque is found to not be significant compared to the driving torque of industrial motors. Hence the use of torsional vibrations as a mean to detect lubrication starvation is limited to applications in which bearing friction could impact the performance of the rotor drastically. The results are verified by the experiments in which the torsional vibrations are not able to detect changes in lubrication conditions. Finally, an energy analysis is presented to study the impact of lubrication starvation in the motor efficiency, which could be an economical motivator to encourage the research of condition monitoring of lubrication starvation. Lubrication starvation decreases the efficiency by dissipating power as heat and is dependent on the speed and static load rather than the load factor of the motor. Advisors/Committee Members: Rasmussen, Bryan P (advisor), Won-Jong, Kim (committee member), der%20S%22%29&pagesize-30">Suh, Chii-der S (committee member), Sanchez-Sinencio, Edgar (committee member).

Subjects/Keywords: Ball-bearing; Lubrication Starvation; Detection; Diagnosis

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APA (6^th Edition):

Mijares Tobias, J. A. (2018). Detection of Lubrication Starvation in Ball Bearings by Means of Lateral and Torsional Vibrations. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/173315

Chicago Manual of Style (16^th Edition):

Mijares Tobias, Jorge Arturo. “Detection of Lubrication Starvation in Ball Bearings by Means of Lateral and Torsional Vibrations.” 2018. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/173315.

MLA Handbook (7^th Edition):

Mijares Tobias, Jorge Arturo. “Detection of Lubrication Starvation in Ball Bearings by Means of Lateral and Torsional Vibrations.” 2018. Web. 22 Apr 2021.

Vancouver:

Mijares Tobias JA. Detection of Lubrication Starvation in Ball Bearings by Means of Lateral and Torsional Vibrations. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/173315.

Council of Science Editors:

Mijares Tobias JA. Detection of Lubrication Starvation in Ball Bearings by Means of Lateral and Torsional Vibrations. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/173315

Texas A&M University

17. Liu, Peng. Influence of Solid Inclusion Phase on the Mechanical Behavior of Thermoplastic Polymer Composite and Blend.

Degree: PhD, Mechanical Engineering, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/158930

► The objective of this work is to investigate the influences of the solid inclusion phase on the physical and mechanical properties of the thermoplastic polymer… (more)

▼ The objective of this work is to investigate the influences of the solid inclusion phase on the physical and mechanical properties of the thermoplastic polymer composites, as well as the mechanisms that cause the properties’ deterioration upon exposure to hydrothermal environment. In order to obtain fundamental understanding of structure-property relationships of multicomponent polymeric materials, this dissertation work focuses on two important factors, which are the spatial dispersion of the inclusion phase, as well as its interface with the polymer matrix. Two different systems, polypropylene containing multiwalled carbon nanotubes (MWCNTs) and poly(ether ether ketone) (PEEK) containing 50 wt.% of poly(benzimidazole) (PBI) particles were employed as model systems. Remarkable increases in modulus and strength of polypropylene, containing only trace amounts (0.1 wt.%) of individually dispersed F-MWCNTs were observed. The influence of the individually dispersed F-MWCNTs on the morphology of the crystal domains of PP and the mechanisms responsible for the observed increases in modulus and strength were examined. PBI particles (average size 50 μm) were blended as an inclusion phase with PEEK to form a 50:50 weight ratio blend. The objective of this work is to investigate the reinforcing effect of PBI on performance in high temperature operating regimes (above 250°C). The interfacial affinity between PEEK and PBI at various conditions has been systematically studied by investigating the fracture behavior of PEEK/PBI blend. In addition, all samples were studied by polarized optical microscopy and dynamic mechanical analysis (DMA) to establish correlation between the morphology and properties. An underexplored aspect of this blend system is connected with the tendency of the PBI component to absorb and retain significant amounts of moisture. The effect of retained moisture on the performance of this type of blend in certain application environments is poorly understood. This dissertation work investigates the mechanisms that cause the mechanical property deterioration of PEEK/PBI blends on exposure to hot water at 288°C. In order to determine the underlying physics linked to property decrease, PEEK/PBI blends were subjected to several different treatments prior to characterization. Advisors/Committee Members: Sue, Hung-Jue (advisor), Bergbreiter, David (committee member), Creasy, Terry (committee member), Der%22%29&pagesize-30">Suh, Chii-Der (committee member).

Subjects/Keywords: polymer; mechanical property; structure-property relationship

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APA (6^th Edition):

Liu, P. (2016). Influence of Solid Inclusion Phase on the Mechanical Behavior of Thermoplastic Polymer Composite and Blend. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/158930

Chicago Manual of Style (16^th Edition):

Liu, Peng. “Influence of Solid Inclusion Phase on the Mechanical Behavior of Thermoplastic Polymer Composite and Blend.” 2016. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/158930.

MLA Handbook (7^th Edition):

Liu, Peng. “Influence of Solid Inclusion Phase on the Mechanical Behavior of Thermoplastic Polymer Composite and Blend.” 2016. Web. 22 Apr 2021.

Vancouver:

Liu P. Influence of Solid Inclusion Phase on the Mechanical Behavior of Thermoplastic Polymer Composite and Blend. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/158930.

Council of Science Editors:

Liu P. Influence of Solid Inclusion Phase on the Mechanical Behavior of Thermoplastic Polymer Composite and Blend. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/158930

Texas A&M University

18. Mao, Xu. Ultrafast Laser Induced Thermo-elasto-plastodynamics in Polycrystalline Metals.

Degree: PhD, Mechanical Engineering, 2018, Texas A&M University

URL: http://hdl.handle.net/1969.1/192055

► A comprehensive thermo-elasto-plastodynamic model of the laser-material interaction in polycrystalline metals in response to ultrafast laser heating is formulated. Lacking a fundamental understanding for the… (more)

▼ A comprehensive thermo-elasto-plastodynamic model of the laser-material interaction in polycrystalline metals in response to ultrafast laser heating is formulated. Lacking a fundamental understanding for the non-ablation and non-melting ablation processes and the underlying mechanism that governs coupled thermal-mechanical generation impedes the broader application of ultrashort lasers. The transport dynamics established in the dissertation describes the initial plasma plumes as the result of the photoelectric and thermionic emissions of electrons. The formulation admits finite electron and lattice energy transport speeds and incorporates energy losses to electrons emission and thermoelastic and thermoplastic generations. Elastic-plastic constitutive laws are incorporated to describe the complex elasto-plastodynamic cyclic behaviors attributed to the rapid thermal processing and metallic characteristics of the Bauschinger’ effect. A staggered-grid finite difference scheme is time-integrated to resolve the coupled field responses using a one-dimensional formulation and an axisymmetric model. The balance equations considered in the research obey the principle of energy conservation and follow the characteristic time scales associated with optical energy absorption, particle emission, and electron and lattice relaxations. Electron energy transport in polycrystalline metals is comprehensively investigated by considering temperature-dependent thermophysical properties and the grain size effects due to surface and grain boundary scatterings. Numerical results obtained for the non-ablation of a gold film under ultrafast optical heating is favorably examined against published experimental data for model validation. Parametric studies considering target thickness, grain size, and optical parameters indicate the impact of these parameters on energy transport, electrons emission, and coupled thermal-mechanical response. Crack initiation is investigated by considering the propagation of stress waves generated by non-ablation heating. The novel concept of power density is adopted as the energy rate-based criterion to evaluate ablation mass removal and ablation depth as functions of laser fluence. The thermo-elasto-plastodynamic formulation is feasible for describing non-ablation thermoelastic generation and for exploring the correlation between the incident laser pulse and ablation and damage in polycrystalline metals. Advisors/Committee Members: Der%20S.%22%29&pagesize-30">Suh, Chii-Der S. (advisor), Wang, Jyhwen (committee member), Fang, Alex (committee member), Wen, Sy-Bor (committee member).

Subjects/Keywords: ultrafast laser; thermo-elasto-dynamics; thermo-elasto-plasto-dynamics; polycrystalline metal

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APA (6^th Edition):

Mao, X. (2018). Ultrafast Laser Induced Thermo-elasto-plastodynamics in Polycrystalline Metals. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/192055

Chicago Manual of Style (16^th Edition):

Mao, Xu. “Ultrafast Laser Induced Thermo-elasto-plastodynamics in Polycrystalline Metals.” 2018. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/192055.

MLA Handbook (7^th Edition):

Mao, Xu. “Ultrafast Laser Induced Thermo-elasto-plastodynamics in Polycrystalline Metals.” 2018. Web. 22 Apr 2021.

Vancouver:

Mao X. Ultrafast Laser Induced Thermo-elasto-plastodynamics in Polycrystalline Metals. [Internet] [Doctoral dissertation]. Texas A&M University; 2018. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/192055.

Council of Science Editors:

Mao X. Ultrafast Laser Induced Thermo-elasto-plastodynamics in Polycrystalline Metals. [Doctoral Dissertation]. Texas A&M University; 2018. Available from: http://hdl.handle.net/1969.1/192055

19. Liu, Mengke. Investigation on the Applicability of Active Magnetic Bearings to High Speed Spindle Design.

Degree: MS, Mechanical Engineering, 2015, Texas A&M University

URL: http://hdl.handle.net/1969.1/161245

► A novel concept applicable to the control of spindles at high speed is developed by using active magnetic bearings (AMBs) that are non-contact and of… (more)

▼ A novel concept applicable to the control of spindles at high speed is developed by using active magnetic bearings (AMBs) that are non-contact and of low vibration. Extensive literature reviews explicate that the broad applications of AMBs are severely hampered by the incomplete description of the underlying electro-magnetic-mechanical dynamics. The thesis considers the gyroscopic effect inherent of a flexible rotor and explores the geometry coupling of the electro-magnetic actuators to the formulation of a comprehensive nonlinear AMB-rotor model. The model provides the basis for the creation of a novel time-frequency control algorithm whose derivation requires no linearization or mathematical simplification of any kind, thus allowing the model system to retain its true fundamental characteristics. Unlike proportional-integral-derivative (PID) controllers that are dominant in most if not all AMB configurations, the controller developed for the research is inspired by the wavelet-based nonlinear time-frequency control methodology that incorporates the basic notions of online system identification and adaptive control. Wavelet filter banks and filtered-x least-mean-square (LMS) algorithm are two of the major salient physical features of the controller design, with the former providing concurrent temporal and spectral resolutions needed for identifying nonlinear states of motion and the latter ensuring the dynamic stability of the AMB-rotor system at all operating speeds subjected to the presence of external disturbances. It is shown in the thesis that the vibration of the rotor is unconditionally controlled by maintaining the mandatory 0.55 mm air gap at 150,000 and 187,500 rpm subject to a tight spatial constraint (tolerance) of the order of 0.1375mm. System responses with and without considering the gyroscopic motion and geometry coupling are studied to demonstrate the negative impact on misinterpreting the AMB-rotor dynamics when the two effects are neglected. The case of an impact of 5,000m/s2 in magnitude and 0.001 seconds in duration at 187,500rpm is also investigated to establish the robustness of the controller design. The time responses of all the cases considered are both temporally bounded and spectrally bandwidth-limited, thus demonstrating the effectiveness of the wavelet-based time-frequency controller design in mitigating the inherent instability of the AMB-rotor system at extreme speeds. Advisors/Committee Members: Der%20%20S%22%29&pagesize-30">Suh, Chii-Der S (advisor), Hung, Nguyen (committee member), Kim, Won-Jong (committee member).

Subjects/Keywords: Magnetic Bearings; Nonlinear time-frequency control

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APA (6^th Edition):

Liu, M. (2015). Investigation on the Applicability of Active Magnetic Bearings to High Speed Spindle Design. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/161245

Chicago Manual of Style (16^th Edition):

Liu, Mengke. “Investigation on the Applicability of Active Magnetic Bearings to High Speed Spindle Design.” 2015. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/161245.

MLA Handbook (7^th Edition):

Liu, Mengke. “Investigation on the Applicability of Active Magnetic Bearings to High Speed Spindle Design.” 2015. Web. 22 Apr 2021.

Vancouver:

Liu M. Investigation on the Applicability of Active Magnetic Bearings to High Speed Spindle Design. [Internet] [Masters thesis]. Texas A&M University; 2015. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/161245.

Council of Science Editors:

Liu M. Investigation on the Applicability of Active Magnetic Bearings to High Speed Spindle Design. [Masters Thesis]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/161245

20. Sonawane, Mahesh. Buckling analysis of singly curved shallow bi-layered arch under concentrated loading.

Degree: MS, Mechanical Engineering, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-1576

► Bi-layered materials are a reduced weight derivative of the sandwich structure and are comprised of one thin skin face reinforced by a thick layer of… (more)

Subjects/Keywords: buckling; bi-layer; sandwich; stability

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APA (6^th Edition):

Sonawane, M. (2009). Buckling analysis of singly curved shallow bi-layered arch under concentrated loading. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1576

Chicago Manual of Style (16^th Edition):

Sonawane, Mahesh. “Buckling analysis of singly curved shallow bi-layered arch under concentrated loading.” 2009. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-1576.

MLA Handbook (7^th Edition):

Sonawane, Mahesh. “Buckling analysis of singly curved shallow bi-layered arch under concentrated loading.” 2009. Web. 22 Apr 2021.

Vancouver:

Sonawane M. Buckling analysis of singly curved shallow bi-layered arch under concentrated loading. [Internet] [Masters thesis]. Texas A&M University; 2009. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1576.

Council of Science Editors:

Sonawane M. Buckling analysis of singly curved shallow bi-layered arch under concentrated loading. [Masters Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1576

21. Hsieh, Pin-Chun. Autonomous robotic wheelchair with collision-avoidance navigation.

Degree: MS, Mechanical Engineering, 2008, Texas A&M University

URL: http://hdl.handle.net/1969.1/86037

► The objective of this research is to demonstrate a robotic wheelchair moving in an unknown environment with collision-avoidance navigation. A real-time path-planning algorithm was implemented… (more)

Subjects/Keywords: Robot

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APA (6^th Edition):

Hsieh, P. (2008). Autonomous robotic wheelchair with collision-avoidance navigation. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/86037

Chicago Manual of Style (16^th Edition):

Hsieh, Pin-Chun. “Autonomous robotic wheelchair with collision-avoidance navigation.” 2008. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/86037.

MLA Handbook (7^th Edition):

Hsieh, Pin-Chun. “Autonomous robotic wheelchair with collision-avoidance navigation.” 2008. Web. 22 Apr 2021.

Vancouver:

Hsieh P. Autonomous robotic wheelchair with collision-avoidance navigation. [Internet] [Masters thesis]. Texas A&M University; 2008. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/86037.

Council of Science Editors:

Hsieh P. Autonomous robotic wheelchair with collision-avoidance navigation. [Masters Thesis]. Texas A&M University; 2008. Available from: http://hdl.handle.net/1969.1/86037

22. Kim, Jinseok. A Non-Local Third Order Theory of Functionally Graded Plates Under Electromechanical Coupling Effect.

Degree: PhD, Mechanical Engineering, 2017, Texas A&M University

URL: http://hdl.handle.net/1969.1/161273

► In this research, a general nonlinear third-order plate theory has been developed using the principle of virtual displacements. The developed theory is based on geometric… (more)

▼ In this research, a general nonlinear third-order plate theory has been developed using the principle of virtual displacements. The developed theory is based on geometric nonlinearity, size effects of structures in micro scale, functionally graded materials, and piezoelectric effects. The von Kármán nonlinear strains, i.e., small strain and moderate rotation, are considered to represent geometric nonlinearity. A modified couple stress theory is adopted to capture microstructure dependent size effect. A power law distribution is used to represent the variation of two material constituents through thickness. The developed plate theory is also specialized to classical, first order shear deformation, and Reddy third order plate theories. Analytical solutions for the developed plate theory are presented using the Navier solution technique. All dependent variables are assumed to be forms of double trigonometric functions which satisfy the boundary conditions. The analytical solutions are limited to geometric linearity and simply supported plates. Examples of bending, buckling, and vibration problems are presented to show effects of the power-law distribution of two materials and the microstructure-dependent size parameter. The nonlinear finite element model based on the developed plate theory is carried out to study of the static bending problems regarding the size effects of microstructure, geometric nonlinearity, and power-law variation of the material composition through the thickness. The principle of virtual work is utilized to develop a displacement based weak-form Galerkin finite element model which requires C¹ continuity of all dependent variables. A conforming element is implemented using Hermite type interpolation functions. The piezoelectric effect is considered for functionally graded smart plates which have surface-mounted piezoelectric layers, and a functionally graded core layer. The formulation includes the coupling between mechanical deformations and the charge equations of electrostatics. In addition to the kinematic assumption of the developed plate theory, the potential function is assumed to be the combination of half cosine variation of electric potential and linear variation of applied voltage on outer surfaces. An analytical solution and a finite element model are obtained. A parametric study is presented to show effects of thickness ratio between core layer and piezoelectric layers in addition to material variation of core plate and micro structure size effects. Advisors/Committee Members: Reddy, Junuthula N. (advisor), Muliana, Anastasia H. (committee member), Der%20S.%22%29&pagesize-30">Suh, Chii-Der S. (committee member), Hueste, Mary Beth (committee member).

Subjects/Keywords: Third-order shear deformation plate theory; functionally graded materials; piezoelectric materials; modi ed couple stress theory; geometric nonlinearity

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APA (6^th Edition):

Kim, J. (2017). A Non-Local Third Order Theory of Functionally Graded Plates Under Electromechanical Coupling Effect. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/161273

Chicago Manual of Style (16^th Edition):

Kim, Jinseok. “A Non-Local Third Order Theory of Functionally Graded Plates Under Electromechanical Coupling Effect.” 2017. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/161273.

MLA Handbook (7^th Edition):

Kim, Jinseok. “A Non-Local Third Order Theory of Functionally Graded Plates Under Electromechanical Coupling Effect.” 2017. Web. 22 Apr 2021.

Vancouver:

Kim J. A Non-Local Third Order Theory of Functionally Graded Plates Under Electromechanical Coupling Effect. [Internet] [Doctoral dissertation]. Texas A&M University; 2017. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/161273.

Council of Science Editors:

Kim J. A Non-Local Third Order Theory of Functionally Graded Plates Under Electromechanical Coupling Effect. [Doctoral Dissertation]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/161273

23. Oh, Yoonchan. Multi-physics investigation on the failure mechanism and short-time scale wave motion in flip-chip configuration.

Degree: PhD, Mechanical Engineering, 2005, Texas A&M University

URL: http://hdl.handle.net/1969.1/2719

► The demands for higher clock speeds and larger current magnitude in high-performance flip-chip electronic packaging configurations of small footprint have inevitably raised the concern over… (more)

▼ The demands for higher clock speeds and larger current magnitude in high-performance flip-chip electronic packaging configurations of small footprint have inevitably raised the concern over rapid thermal transients and large thermal spatial gradients that could severely compromise package performance. Coupled electrical-thermal-mechanical multi-physics were explored to evaluate the concern and to establish the knowledge base necessary for improving flip-chip reliability. It was found that within the first few hundred nanoseconds upon power-on, there were fast attenuating, dispersive shock waves of extremely high frequency propagating in the package. The notions of high cycle fatigue, power density and joint time-frequency analysis were employed to characterize the waves and the various failure modes associated with the moving of these short-lived dynamical disturbances in bulk materials and along interfaces. A qualitative measure for failure was also developed which enables the extent of damages inflicted by short-time wave propagation to be calculated in the probability sense. Failure modes identified in this study are all in agreement with what have been observed in industry. This suggests that micron cracks or interfacial flaws initiated at the short-time scale would be further propagated by the CTE-induced thermal stresses at the long-time scale and result in eventual electrical disruptions. Although epoxy-based underfills with fillers were shown to be effective in alleviating thermal stresses and improving solder joint fatigue performance in thermal cycling tests of long-time scale, underfill material viscoelasticity was found to be insignificant in attenuating short-time scale wave propagation. On the other hand, the inclusion of Cu interconnecting layers in flip-chips was shown to perform significantly better than Al layers in suppressing short-time scale effects. These results imply that, if improved flip-chip reliability is to be achieved, all packaging constituent materials need to be formulated to have well-defined short-time scale and long-time scale properties. In addition, the results also suggest that the composition and layout of all packaging components be optimized to achieve discouraging or suppressing short-time scale dynamic effects. In summary, results reported herein and numerical procedures developed for the research would not just render higher packaging manufacturing yield, but also bring out significant impact on packaging development, packaging material formulation and micro-circuit layout design. Advisors/Committee Members: Der%20S.%22%29&pagesize-30">Suh, Chii-Der S. (advisor), Hogan, Harry (committee member), Roschke, Paul N. (committee member), Morgan, Roger (committee member).

Subjects/Keywords: electronic packaging

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APA (6^th Edition):

Oh, Y. (2005). Multi-physics investigation on the failure mechanism and short-time scale wave motion in flip-chip configuration. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/2719

Chicago Manual of Style (16^th Edition):

Oh, Yoonchan. “Multi-physics investigation on the failure mechanism and short-time scale wave motion in flip-chip configuration.” 2005. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/2719.

MLA Handbook (7^th Edition):

Oh, Yoonchan. “Multi-physics investigation on the failure mechanism and short-time scale wave motion in flip-chip configuration.” 2005. Web. 22 Apr 2021.

Vancouver:

Oh Y. Multi-physics investigation on the failure mechanism and short-time scale wave motion in flip-chip configuration. [Internet] [Doctoral dissertation]. Texas A&M University; 2005. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/2719.

Council of Science Editors:

Oh Y. Multi-physics investigation on the failure mechanism and short-time scale wave motion in flip-chip configuration. [Doctoral Dissertation]. Texas A&M University; 2005. Available from: http://hdl.handle.net/1969.1/2719

24. Qi, Xuele. Ultrafast Laser Induced Thermo-Elasto-Visco-Plastodynamics in Single Crystalline Silicon.

Degree: PhD, Mechanical Engineering, 2011, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7393

► A comprehensive model for describing the fundamental mechanism dictating the interaction of ultrafast laser pulse with single crystalline silicon wafer is formulated. The need for… (more)

▼ A comprehensive model for describing the fundamental mechanism dictating the interaction of ultrafast laser pulse with single crystalline silicon wafer is formulated. The need for establishing the feasibility of employing lasers of subpicosecond pulse width in Laser Induced Stress Waves Thermometry (LISWT) for single crystalline silicon processing motivated the work. The model formulation developed is of a hyperbolic type capable of characterizing non-thermal melting and thermo-elastoviscoplastic deformation as functions of laser input parameters and ambient temperature. A plastic constitutive law is followed to describe the complex elasto-viscoplastic responses in silicon undergoing Rapid Thermal Processing (RTP) annealing at elevated temperatures. A system of nine first-order hyperbolic equations applicable to describing 3-D elasto-viscoplastic wave motions in silicon is developed. The group velocities of certain selected frequency components are shown to be viable thermal indicators, thus establishing the feasibility of exploiting nanosecond laser induced propagating stress waves for the high-resolution thermal profiling of silicon wafers. Femtosecond laser induced transport dynamics in silicon is formulated based on the relaxation-time approximation of the Boltzmann equation. Temperature-dependent multi-phonons, free-carrier absorptions, and the recombination and impact ionization processes governing the laser model and carrier numbers are considered using a set of balance equations. The balance equation of lattice energy and equations of motion of both parabolic and hyperbolic types are derived to describe the complex thermo-elastoplastodynamic behaviors of the material in response to ultrafast laser pulsing. The solution strategy implemented includes a multi-time scale axisymmetric model of finite geometry and a staggered-grid finite difference scheme that allows both velocity and stress be simultaneously determined without having to solve for displacements. Transport phenomena initiated by femtosecond pulses including the spatial and temporal evolutions of electron and lattice temperatures, along with electron-hole carrier density, are found to be functions of laser fluence and pulse width. The femtosecond laser heating model that admits hyperbolic energy transport is shown to remedy the dilemma that thermal disturbances propagate with infinite speed. Non-thermal melting fluence is examined favorably against published experimental data. That it is feasible to explore femtosecond laser induced displacement and stress components for 1K resolution thermal profiling is one of the conclusions reached. Advisors/Committee Members: Der%22%29&pagesize-30">Suh, Chii-Der (advisor), Sue, Hung-Jue (committee member), Fry, Gary (committee member), Wang, Jyhwen (committee member).

Subjects/Keywords: Single Crysalline Silicon; Ultrafast Laser; Thermo-elasto-visco-plastodynamics; Laser Induced Stress Waves Thermometry

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APA (6^th Edition):

Qi, X. (2011). Ultrafast Laser Induced Thermo-Elasto-Visco-Plastodynamics in Single Crystalline Silicon. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7393

Chicago Manual of Style (16^th Edition):

Qi, Xuele. “Ultrafast Laser Induced Thermo-Elasto-Visco-Plastodynamics in Single Crystalline Silicon.” 2011. Doctoral Dissertation, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7393.

MLA Handbook (7^th Edition):

Qi, Xuele. “Ultrafast Laser Induced Thermo-Elasto-Visco-Plastodynamics in Single Crystalline Silicon.” 2011. Web. 22 Apr 2021.

Vancouver:

Qi X. Ultrafast Laser Induced Thermo-Elasto-Visco-Plastodynamics in Single Crystalline Silicon. [Internet] [Doctoral dissertation]. Texas A&M University; 2011. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7393.

Council of Science Editors:

Qi X. Ultrafast Laser Induced Thermo-Elasto-Visco-Plastodynamics in Single Crystalline Silicon. [Doctoral Dissertation]. Texas A&M University; 2011. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-12-7393

Texas A&M University

25. Auviur Srinivasa, Nandagopalan. Adaptive mesh refinement for a finite difference scheme using a quadtree decomposition approach.

Degree: MS, Mechanical Engineering, 2009, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-1144

► Some numerical simulations of multi-scale physical phenomena consume a significant amount of computational resources, since their domains are discretized on high resolution meshes. An enormous… (more)

▼ Some numerical simulations of multi-scale physical phenomena consume a significant amount of computational resources, since their domains are discretized on high resolution meshes. An enormous wastage of these resources occurs in refinement of sections of the domain where computation of the solution does not require high resolutions. This problem is effectively addressed by adaptive mesh refinement (AMR), a technique of local refinement of a mesh only in sections where needed, thus allowing concentration of effort where it is required. Sections of the domain needing high resolution are generally determined by means of a criterion which may vary depending on the nature of the problem. Fairly straightforward criteria could include comparing the solution to a threshold or the gradient of a solution, that is, its local rate of change to a threshold. While the former criterion is not particularly rigorous and hardly ever represents a physical phenomenon of interest, it is simple to implement. However, the gradient criterion is not as simple to implement as a direct comparison of values, but it is still quick and a good indicator of the effectiveness of the AMR technique. The objective of this thesis is to arrive at an adaptive mesh refinement algorithm for a finite difference scheme using a quadtree decomposition approach. In the AMR algorithm developed, a mesh of increasingly fine resolution permits high resolution computation in sub-domains of interest and low resolution in others. In this thesis work, the gradient of the solution has been considered as the criterion determining the regions of the domain needing refinement. Initial tests using the AMR algorithm demonstrate that the paradigm adopted has considerable promise for a variety of research problems. The tests performed thus far depict that the quantity of computational resources consumed is significantly less while maintaining the quality of the solution. Analysis included comparison of results obtained with analytical solutions for four test problems, as well as a thorough study of a contemporary problem in solid mechanics. Advisors/Committee Members: Srinivasa, Arun R. (advisor), Pasciak, Joe (committee member), Der%22%29&pagesize-30">Suh, Chii-Der (committee member).

Subjects/Keywords: Mesh Refinement; Quadtrees

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APA (6^th Edition):

Auviur Srinivasa, N. (2009). Adaptive mesh refinement for a finite difference scheme using a quadtree decomposition approach. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-1144

Chicago Manual of Style (16^th Edition):

Auviur Srinivasa, Nandagopalan. “Adaptive mesh refinement for a finite difference scheme using a quadtree decomposition approach.” 2009. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-1144.

MLA Handbook (7^th Edition):

Auviur Srinivasa, Nandagopalan. “Adaptive mesh refinement for a finite difference scheme using a quadtree decomposition approach.” 2009. Web. 22 Apr 2021.

Vancouver:

Auviur Srinivasa N. Adaptive mesh refinement for a finite difference scheme using a quadtree decomposition approach. [Internet] [Masters thesis]. Texas A&M University; 2009. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1144.

Council of Science Editors:

Auviur Srinivasa N. Adaptive mesh refinement for a finite difference scheme using a quadtree decomposition approach. [Masters Thesis]. Texas A&M University; 2009. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-1144

Texas A&M University

26. Parthasarathy, Nikhil Kaushik. An efficient algorithm for blade loss simulations applied to a high-order rotor dynamics problem.

Degree: MS, Mechanical Engineering, 2004, Texas A&M University

URL: http://hdl.handle.net/1969.1/189

► In this thesis, a novel approach is presented for blade loss simulation of an aircraft gas turbine rotor mounted on rolling element bearings with squeeze… (more)

Subjects/Keywords: Blade loss; Modal truncation augmentation; Dual rotor aircraft engine; Computational efficiency; high fidelity bearings

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APA (6^th Edition):

Parthasarathy, N. K. (2004). An efficient algorithm for blade loss simulations applied to a high-order rotor dynamics problem. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/189

Chicago Manual of Style (16^th Edition):

Parthasarathy, Nikhil Kaushik. “An efficient algorithm for blade loss simulations applied to a high-order rotor dynamics problem.” 2004. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/189.

MLA Handbook (7^th Edition):

Parthasarathy, Nikhil Kaushik. “An efficient algorithm for blade loss simulations applied to a high-order rotor dynamics problem.” 2004. Web. 22 Apr 2021.

Vancouver:

Parthasarathy NK. An efficient algorithm for blade loss simulations applied to a high-order rotor dynamics problem. [Internet] [Masters thesis]. Texas A&M University; 2004. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/189.

Council of Science Editors:

Parthasarathy NK. An efficient algorithm for blade loss simulations applied to a high-order rotor dynamics problem. [Masters Thesis]. Texas A&M University; 2004. Available from: http://hdl.handle.net/1969.1/189

Texas A&M University

27. Nagaraj, Mahavir. Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration.

Degree: MS, Mechanical Engineering, 2004, Texas A&M University

URL: http://hdl.handle.net/1969.1/1087

► The generalized theory of thermoelasticity was employed to characterize the coupled thermal and mechanical wave propagation in high performance microelectronic packages. Application of a Gaussian… (more)

Subjects/Keywords: electronic packaging; thermal mechanical; thermomechanical; flip chip; shock wave; reliability; green lindsay; generalized thermoelasticity

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APA (6^th Edition):

Nagaraj, M. (2004). Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/1087

Chicago Manual of Style (16^th Edition):

Nagaraj, Mahavir. “Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration.” 2004. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/1087.

MLA Handbook (7^th Edition):

Nagaraj, Mahavir. “Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration.” 2004. Web. 22 Apr 2021.

Vancouver:

Nagaraj M. Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration. [Internet] [Masters thesis]. Texas A&M University; 2004. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/1087.

Council of Science Editors:

Nagaraj M. Short time scale thermal mechanical shock wave propagation in high performance microelectronic packaging configuration. [Masters Thesis]. Texas A&M University; 2004. Available from: http://hdl.handle.net/1969.1/1087

Texas A&M University

28. Vedantham, Vikram. In-situ temperature and thickness characterization for silicon wafers undergoing thermal annealing.

Degree: MS, Mechanical Engineering, 2004, Texas A&M University

URL: http://hdl.handle.net/1969.1/1181

► Nano scale processing of IC chips has become the prime production technique as the microelectronic industry aims towards scaling down product dimensions while increasing accuracy… (more)

▼ Nano scale processing of IC chips has become the prime production technique as the microelectronic industry aims towards scaling down product dimensions while increasing accuracy and performance. Accurate control of temperature and a good monitoring mechanism for thickness of the deposition layers during epitaxial growth are critical parameters influencing a good yield. The two-fold objective of this thesis is to establish the feasibility of an alternative to the current pyrometric and ellipsometric techniques to simultaneously measure temperature and thickness during wafer processing. TAP-NDE is a non-contact, non-invasive, laser-based ultrasound technique that is employed in this study to contemporarily profile the thermal and spatial characteristics of the wafer. The Gabor wavelet transform allows the wave dispersion to be unraveled and the group velocity of individual frequency components to be extracted from the experimentally acquired time waveform. The thesis illustrates the formulation of a theoretical model that is used to identify the frequencies sensitive to temperature and thickness changes. The group velocity of the corresponding frequency components is determined and their corresponding changes with respect to temperature for different thickness are analytically modeled. TAP-NDE is then used to perform an experimental analysis on Silicon wafers of different thickness to determine the maximum possible resolution of TAP-NDE towards temperature sensitivity, and to demonstrate the ability to differentiate between wafers of different deposition layer thickness at temperatures up to 600?C. Temperature resolution is demonstrated for ?10?C resolution and for ?5?C resolution; while thickness differentiation is carried out with wafers carrying 4000? and 8000? of aluminum deposition layer. The experimental group velocities of a set of selected frequency components extracted using the Gabor Wavelet time-frequency analysis as compared to their corresponding theoretical group velocities show satisfactory agreement. As a result of this work, it is seen that TAP-NDE is a suitable tool to identify and characterize thickness and temperature changes simultaneously during thermal annealing that can replace the current need for separate characterization of these two important parameters in semiconductor manufacturing. Advisors/Committee Members: Der%20S.%22%29&pagesize-30">Suh, Chii-Der S. (advisor), Chan, Andrew K. (committee member), Chona, Ravinder (committee member).

Subjects/Keywords: Ultrasonics; Wave Propagation; Silicon Wafers; RTP; Thermal Processing; wafer; Thermal Annealing; Lamb waves; Signal Processing; Gabor Wavelet Transform; Wavelet Transform; Group Velocity; Semiconductor

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APA (6^th Edition):

Vedantham, V. (2004). In-situ temperature and thickness characterization for silicon wafers undergoing thermal annealing. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/1181

Chicago Manual of Style (16^th Edition):

Vedantham, Vikram. “In-situ temperature and thickness characterization for silicon wafers undergoing thermal annealing.” 2004. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/1181.

MLA Handbook (7^th Edition):

Vedantham, Vikram. “In-situ temperature and thickness characterization for silicon wafers undergoing thermal annealing.” 2004. Web. 22 Apr 2021.

Vancouver:

Vedantham V. In-situ temperature and thickness characterization for silicon wafers undergoing thermal annealing. [Internet] [Masters thesis]. Texas A&M University; 2004. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/1181.

Council of Science Editors:

Vedantham V. In-situ temperature and thickness characterization for silicon wafers undergoing thermal annealing. [Masters Thesis]. Texas A&M University; 2004. Available from: http://hdl.handle.net/1969.1/1181

Texas A&M University

29. Lo, Tzu-Wei. A new sensor concept for simultaneous measurement of pressure, temperature and thickness of plate structures using modified wave propagation theory.

Degree: MS, Mechanical Engineering, 2005, Texas A&M University

URL: http://hdl.handle.net/1969.1/2598

► This thesis presents a multi-purpose sensor concept viable for the simultaneous measurement of pressure, temperature and thickness of plate structures. It also establishes the knowledge… (more)

▼ This thesis presents a multi-purpose sensor concept viable for the simultaneous measurement of pressure, temperature and thickness of plate structures. It also establishes the knowledge base necessary for future sensor design. Thermal-Acousto Photonic Non-Destructive Evaluation (TAP-NDE) is employed to remotely initiate and acquire interrogating ultrasonic waves. Parameters including pressure, temperature and plate thickness are determined through exploring the dispersion features of the interrogating waves. A theoretical study is performed, through which a modified wave propagation theory applicable to homogeneous, isotropic, linear elastic materials is formulated along with an associated numerical model. A numerical scheme for solving the model is also developed using FEMLAB, a finite element based PDE solver. Gabor Wavelet Transform (GWT) is employed to map numerical time waveforms into the joint time-frequency domain. Wave time-frequency information enables dispersion curves to be extracted and material pressure, temperature and thickness to be determined. A sensor configuration design integrating the wave generation and sensing components of the proven TAP-NDE technology is also developed. Conclusions of the research are drawn from wave dispersion obtained corresponding to the following ranges of parameters: 300-500kHz for frequency, 25-300 °C for temperature, 1-3mm for plate thickness, and 6 10 1?? - 7 1 10 ?? N/m for pressure. Each of the three parameters considered in the study has a different level of impact on plate wave dispersion. Plate thickness is found to have the most impact on wave dispersion, followed by temperature of the plate. The effect attributable to pressure is the least prominent among the three parameters considered. Plate thickness and temperature can be readily measured while simultaneously resolved using dispersion curves. However, pressure variation can only be differentiated when the plate is smaller than 1mm in thickness. It is observed that the thicker the plate, the faster the frequency group velocity. Also, the group velocities of all frequency components considered are seen to increase with increasing temperature, but decrease with increasing pressure. Advisors/Committee Members: Der%20S.%22%29&pagesize-30">Suh, Chii-Der S. (advisor), Hung, Wayne N. P. (committee member), Kim, Won-Jong (committee member).

Subjects/Keywords: new sensor; pressure; temperature; thickness of plate structures; modified wave propagation theory

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lo, T. (2005). A new sensor concept for simultaneous measurement of pressure, temperature and thickness of plate structures using modified wave propagation theory. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/2598

Chicago Manual of Style (16^th Edition):

Lo, Tzu-Wei. “A new sensor concept for simultaneous measurement of pressure, temperature and thickness of plate structures using modified wave propagation theory.” 2005. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/2598.

MLA Handbook (7^th Edition):

Lo, Tzu-Wei. “A new sensor concept for simultaneous measurement of pressure, temperature and thickness of plate structures using modified wave propagation theory.” 2005. Web. 22 Apr 2021.

Vancouver:

Lo T. A new sensor concept for simultaneous measurement of pressure, temperature and thickness of plate structures using modified wave propagation theory. [Internet] [Masters thesis]. Texas A&M University; 2005. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/2598.

Council of Science Editors:

Lo T. A new sensor concept for simultaneous measurement of pressure, temperature and thickness of plate structures using modified wave propagation theory. [Masters Thesis]. Texas A&M University; 2005. Available from: http://hdl.handle.net/1969.1/2598

Texas A&M University

30. Huang, Chang-Chia. Short-Time Scale Dynamic Failure Modes in a Through-Silicon-Via (TSV) Flip-Chip Configuration.

Degree: MS, Mechanical Engineering, 2010, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7037

► The demand for high performance microelectronic products drives the development of 3-D chip-stacking structure. By the introduction of through-silicon-via (TSV) into 3-D flip-chip packages, microelectronic… (more)

▼ The demand for high performance microelectronic products drives the development of 3-D chip-stacking structure. By the introduction of through-silicon-via (TSV) into 3-D flip-chip packages, microelectronic performance is improved by increasing circuit capacity and diminishing signal delay. However, TSV-embedded structure also raises concerns over many reliability issues that come with the steep thermal and mechanical transient responses, increasing numbers of bi-material interfaces and reduced component sizes. In this research, defect initiation induced by thermalmechanical phenomena is studied to establish the early failure modes within 3-D flip-chip packages. It is found that low amplitude but extremely high frequency thermal stress waves would occur and attenuate rapidly in the first hundreds of nanoseconds upon power-on. Although the amplitude of these waves is far below material yielding points, their intrinsic characteristics of high frequency and high power density are capable of compromising the integrity of all flip-chip components. By conducting spectral analysis of the stress waves and applying the methodology of accumulated damage evaluation, it is demonstrated that micron crack initiation and interconnect debond are highly probable in the immediate proximity of the heat source. Such a negative impact exerted by the stress wave in the early, while brief, transient period is recognized as the short time scale dynamic effect. Researched results strongly indicate that short-time scale effects would inflict very serious reliability issues in 3-D flip-chip packages. The fact that 3-D flip-chip packages accommodate a large amount of reduced-size interconnects makes it vulnerable to the attack of short time scale propagating stress waves. In addition, the stacking structure also renders shearing effect extremely detrimental to 3-D flip-chip integrity. Finally, several guidelines effective in discouraging short-time scale effects and thus improving TSV flip-chip package reliability are proposed Advisors/Committee Members: Der%20S.%22%29&pagesize-30">Suh, Chii-Der S. (advisor), Muliana, Anastasia (committee member), Hurlebaus, Stefan (committee member).

Subjects/Keywords: Flip-chip packages; Reliability; Short-time scale

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Huang, C. (2010). Short-Time Scale Dynamic Failure Modes in a Through-Silicon-Via (TSV) Flip-Chip Configuration. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7037

Chicago Manual of Style (16^th Edition):

Huang, Chang-Chia. “Short-Time Scale Dynamic Failure Modes in a Through-Silicon-Via (TSV) Flip-Chip Configuration.” 2010. Masters Thesis, Texas A&M University. Accessed April 22, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7037.

MLA Handbook (7^th Edition):

Huang, Chang-Chia. “Short-Time Scale Dynamic Failure Modes in a Through-Silicon-Via (TSV) Flip-Chip Configuration.” 2010. Web. 22 Apr 2021.

Vancouver:

Huang C. Short-Time Scale Dynamic Failure Modes in a Through-Silicon-Via (TSV) Flip-Chip Configuration. [Internet] [Masters thesis]. Texas A&M University; 2010. [cited 2021 Apr 22]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7037.

Council of Science Editors:

Huang C. Short-Time Scale Dynamic Failure Modes in a Through-Silicon-Via (TSV) Flip-Chip Configuration. [Masters Thesis]. Texas A&M University; 2010. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2009-08-7037

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Open Access Theses and Dissertations