subject:( Variable sweep wing)

RMIT University

1. Guo, D. Modelling and experimental investigations of a bi-modal unmanned underwater/air system.

Degree: 2019, RMIT University

URL: http://researchbank.rmit.edu.au/view/rmit:162852

► The ability to perform underwater and coastal area monitoring missions without surfacing would increase submarine's safety and its combat ability. An innovative bi-modal unmanned/underwater air… (more)

▼ The ability to perform underwater and coastal area monitoring missions without surfacing would increase submarine's safety and its combat ability. An innovative bi-modal unmanned/underwater air system (BUUAS) and its concept of operations (CONOPS) are proposed to reduce the risk of submarine's exposure. The BUUAS is firstly released from a submerged submarine and travels underwater to keep a distance from the submarine. Then it will exit the water using an innovative propulsion system that would allow a transition from water to air with the purpose of carrying out a planned air mission. When the airborne mission is finished, the BUUAS will dive back into the water and cruise to the submarine to be collected. This study aims to design and develop this system that can achieve the proposed CONOPS. The project addresses three critical aspects, namely, i) the study of an optimised configuration considering both aerodynamic and hydrodynamic performance aspects, ii) the exploration for an effective transition between water/air media and iii) the design of the water/air hybrid propulsion system. A variable-sweep wing configuration with a novel wing-deployment mechanism is considered for an efficient operation in water and air. Numerical simulation, water and wind tunnel experimental tests were conducted to assess the performance characteristics of the propulsion unit in water and the aerodynamic characteristics in air. The assessment data supports the feasibility of the bi-modal vehicle configuration and the stability analysis demonstrates the vehicle has static and dynamic stable behaviour during its flight. The water jet transition propulsion system is powered by pressurized CO2 and was developed to enable a fast take-off transition from water to air. The preliminary design covers the system sizing using an analytical model calibrated by the high-fidelity numerical simulation approach and the design of a specialized gas release mechanism adopted in the propulsion unit. The thrust and launch experiments were performed to verify the transition propulsion system design results and applicability. The air and water experimental results of the customized compact hybrid propulsion system confirm its provision of sufficient power for flight and underwater cruise.

Subjects/Keywords: Fields of Research; BUUAS; Transition propulsion system; Hybrid propulsion system; Variable sweep wing configuration; Wind tunnel test; Numerical simulation; Composite materials; Stability analysis

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APA (6^th Edition):

Guo, D. (2019). Modelling and experimental investigations of a bi-modal unmanned underwater/air system. (Thesis). RMIT University. Retrieved from http://researchbank.rmit.edu.au/view/rmit:162852

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Guo, D. “Modelling and experimental investigations of a bi-modal unmanned underwater/air system.” 2019. Thesis, RMIT University. Accessed January 17, 2021. http://researchbank.rmit.edu.au/view/rmit:162852.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Guo, D. “Modelling and experimental investigations of a bi-modal unmanned underwater/air system.” 2019. Web. 17 Jan 2021.

Vancouver:

Guo D. Modelling and experimental investigations of a bi-modal unmanned underwater/air system. [Internet] [Thesis]. RMIT University; 2019. [cited 2021 Jan 17]. Available from: http://researchbank.rmit.edu.au/view/rmit:162852.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Guo D. Modelling and experimental investigations of a bi-modal unmanned underwater/air system. [Thesis]. RMIT University; 2019. Available from: http://researchbank.rmit.edu.au/view/rmit:162852

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Pretoria

2. [No author]. Longitudinal handling characteristics of a tailless gull-wing aircraft .

Degree: 2008, University of Pretoria

URL: http://upetd.up.ac.za/thesis/available/etd-09182008-132941/

► A handling quality investigation was performed on the swept gull-wing configuration. The swept gull-wing configuration is tailless and has a wing with a transition in… (more)

▼ A handling quality investigation was performed on the swept gull-wing configuration. The swept gull-wing configuration is tailless and has a wing with a transition in the sweep and dihedral angle. An example of this type of aircraft is the Exulans. This aircraft is currently under development at the University of Pretoria. The handling quality study was focussed on pitch axis dynamics. The Exulans is a research testbed that will be used to investigate the swept gull-wing configuration and its special controls by means of full-scale flight testing. Variable wing sweep, twisting elevons and winglets will be investigated as means of control. These control devices are configured in such a way as to have minimum impact on the performance of the aircraft. The handling qualities of the swept gull-wing configuration have to be acceptable while using these different control strategies. The study was launched to investigate whether a gull-wing configuration aircraft will have satisfactory handling qualities at CG positions associated with the most favourable aerodynamic performance. There is an aerodynamic performance gain in designing an aircraft so that the CG falls on the so-called `E-point'. The E-point is the centre of pressure for an elliptical circulation distribution. An elliptical circulation distribution is associated with the highest Oswald efficiency for an aircraft. Time domain simulation techniques and frequency domain analysis techniques were used to analyse the handling qualities of the gull-wing configuration. The C-star criterion was used to analyse handling qualities with time domain simulation data as input. Comparative time domain simulations were performed between the Exulans and other aircraft to compare handling qualities. Eigenvalue analysis was used together with the thumbprint criterion to investigate inherent gull-wing airframe dynamics. The Shomber-Gertsen and Military Specification 8785 criteria were also used for the same purpose. The Neal-Smith method was used to investigate the effect of control authority on handling qualities and the effect of a pilot. The Monnich and Dalldorff criterion was used to evaluate gust handling qualities. An analysis chart by Fremaux and Vairo was used to evaluate the tumbling susceptibility of the gull-wing configuration. The pitch handling quality investigation shows sufficient promise that the swept gull-wing configuration will have acceptable handling qualities with the CG placed at positions associated with optimised aerodynamic performance. Analysis showed that the swept gull-wing configuration is potentially prone to tumbling. With low static margins, the configuration should exhibit improved handling qualities in gusty conditions when compared to existing tailless aircraft. It is recommended that a lateral handling quality study be performed before full scale flight testing commences on the Exulans. In addition, the possibility of wingtip stall must be investigated for the case of the swept gull-wing configuration. Advisors/Committee Members: Theron, Nicolaas J (advisor).

Subjects/Keywords: Flight simulation; Tumbling; Thumbprint criterion; Neal-smith analysis; C-star criterion; Shomber-gertsen analysis; Pilot induced oscillation; Oswald efficiency; Pilot mathematical model; Variable sweep wing; Exulans; Variable static margin; Swept gull-wing configuration; O-point; E-point; Handling qualities; Gust handling qualities; Tailless aircraft; Pecking; Monnich and dalldorff criterion; UCTD

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

APA (6^th Edition):

author], [. (2008). Longitudinal handling characteristics of a tailless gull-wing aircraft . (Masters Thesis). University of Pretoria. Retrieved from http://upetd.up.ac.za/thesis/available/etd-09182008-132941/

Chicago Manual of Style (16^th Edition):

author], [No. “Longitudinal handling characteristics of a tailless gull-wing aircraft .” 2008. Masters Thesis, University of Pretoria. Accessed January 17, 2021. http://upetd.up.ac.za/thesis/available/etd-09182008-132941/.

MLA Handbook (7^th Edition):

author], [No. “Longitudinal handling characteristics of a tailless gull-wing aircraft .” 2008. Web. 17 Jan 2021.

Vancouver:

author] [. Longitudinal handling characteristics of a tailless gull-wing aircraft . [Internet] [Masters thesis]. University of Pretoria; 2008. [cited 2021 Jan 17]. Available from: http://upetd.up.ac.za/thesis/available/etd-09182008-132941/.

Council of Science Editors:

author] [. Longitudinal handling characteristics of a tailless gull-wing aircraft . [Masters Thesis]. University of Pretoria; 2008. Available from: http://upetd.up.ac.za/thesis/available/etd-09182008-132941/

University of Pretoria

3. Agenbag, Daniel Sarel. Longitudinal handling characteristics of a tailless gull-wing aircraft.

Degree: Mechanical and Aeronautical Engineering, 2008, University of Pretoria

URL: http://hdl.handle.net/2263/28011

► A handling quality investigation was performed on the swept gull-wing configuration. The swept gull-wing configuration is tailless and has a wing with a transition in… (more)

▼ A handling quality investigation was performed on the swept gull-wing configuration. The swept gull-wing configuration is tailless and has a wing with a transition in the sweep and dihedral angle. An example of this type of aircraft is the Exulans. This aircraft is currently under development at the University of Pretoria. The handling quality study was focussed on pitch axis dynamics. The Exulans is a research testbed that will be used to investigate the swept gull-wing configuration and its special controls by means of full-scale flight testing. Variable wing sweep, twisting elevons and winglets will be investigated as means of control. These control devices are configured in such a way as to have minimum impact on the performance of the aircraft. The handling qualities of the swept gull-wing configuration have to be acceptable while using these different control strategies. The study was launched to investigate whether a gull-wing configuration aircraft will have satisfactory handling qualities at CG positions associated with the most favourable aerodynamic performance. There is an aerodynamic performance gain in designing an aircraft so that the CG falls on the so-called `E-point'. The E-point is the centre of pressure for an elliptical circulation distribution. An elliptical circulation distribution is associated with the highest Oswald efficiency for an aircraft. Time domain simulation techniques and frequency domain analysis techniques were used to analyse the handling qualities of the gull-wing configuration. The C-star criterion was used to analyse handling qualities with time domain simulation data as input. Comparative time domain simulations were performed between the Exulans and other aircraft to compare handling qualities. Eigenvalue analysis was used together with the thumbprint criterion to investigate inherent gull-wing airframe dynamics. The Shomber-Gertsen and Military Specification 8785 criteria were also used for the same purpose. The Neal-Smith method was used to investigate the effect of control authority on handling qualities and the effect of a pilot. The Monnich and Dalldorff criterion was used to evaluate gust handling qualities. An analysis chart by Fremaux and Vairo was used to evaluate the tumbling susceptibility of the gull-wing configuration. The pitch handling quality investigation shows sufficient promise that the swept gull-wing configuration will have acceptable handling qualities with the CG placed at positions associated with optimised aerodynamic performance. Analysis showed that the swept gull-wing configuration is potentially prone to tumbling. With low static margins, the configuration should exhibit improved handling qualities in gusty conditions when compared to existing tailless aircraft. It is recommended that a lateral handling quality study be performed before full scale flight testing commences on the Exulans. In addition, the possibility of wingtip stall must be investigated for the case of the swept gull-wing configuration. Advisors/Committee Members: Theron, Nicolaas J. (advisor).

Subjects/Keywords: Flight simulation; Tumbling; Thumbprint criterion; Neal-smith analysis; C-star criterion; Shomber-gertsen analysis; Pilot induced oscillation; Oswald efficiency; Pilot mathematical model; Variable sweep wing; Exulans; Variable static margin; Swept gull-wing configuration; O-point; E-point; Handling qualities; Gust handling qualities; Tailless aircraft; Pecking; Monnich and dalldorff criterion; UCTD

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

APA (6^th Edition):

Agenbag, D. (2008). Longitudinal handling characteristics of a tailless gull-wing aircraft. (Masters Thesis). University of Pretoria. Retrieved from http://hdl.handle.net/2263/28011

Chicago Manual of Style (16^th Edition):

Agenbag, Daniel. “Longitudinal handling characteristics of a tailless gull-wing aircraft.” 2008. Masters Thesis, University of Pretoria. Accessed January 17, 2021. http://hdl.handle.net/2263/28011.

MLA Handbook (7^th Edition):

Agenbag, Daniel. “Longitudinal handling characteristics of a tailless gull-wing aircraft.” 2008. Web. 17 Jan 2021.

Vancouver:

Agenbag D. Longitudinal handling characteristics of a tailless gull-wing aircraft. [Internet] [Masters thesis]. University of Pretoria; 2008. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/2263/28011.

Council of Science Editors:

Agenbag D. Longitudinal handling characteristics of a tailless gull-wing aircraft. [Masters Thesis]. University of Pretoria; 2008. Available from: http://hdl.handle.net/2263/28011

University of Manchester

4. El Ouardi, Othman. Design, Analysis And Testing Of An Aircraft Wing Model With Morphing Mechanism.

Degree: 2014, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:237682

► Wing morphing has the potential to significantly improve the performance of an aircraft. The aerospace industry currently relies on control surfaces for changing aircraft wing… (more)

▼ Wing morphing has the potential to significantly improve the performance of an aircraft. The aerospace industry currently relies on control surfaces for changing aircraft wing geometry for different parts of the flight envelope. The needs for reduced fuel consumption and improved flight capability are motivating the aerospace industry to explore alternatives such as wing morphing. Based on this premise, the design, analysis and testing of an aircraft wing model with morphing mechanism is presented. A design study was initially performed to verify the feasibility of the adaptive wing to entirely actuate using shape memory alloy wires (SMA). Finite element method (FEM) was used to assess the capability of the wing to withstand the aerodynamic load and to morph to a desired shape. The actuators’ forces and displacements were also evaluated by finite element simulation.The airframe of a morphing wing, consisting of two ribs made of 14 segments and interconnected through torsional stiffened hinges, was developed. The two ribs were connected through spars with circular cross sections. In the simulation, a skin was considered as the overlapping sliding segments. Morphing of the wing was achieved by displacement of a designed linkage mechanism, using SMA wires installed inside the airframe. The SMA wires connect the front spar to the linkage mechanism via mounting brackets. Torsional and gas springs were considered for providing counter-resisting forces to the system. Actuation occurred by heating the SMA wires through continuous feeding of electric current.Finally, a prototype with rectangular plan section was manufactured and tested so as to demonstrate the morphing capability of the conceived structural layout. The results of the functional test showed high correlation levels with respect to numerical predictions, thus validating the modelling approaches implemented during the design phase. The wing appears to deform smoothly with the induction of very small stresses. A change in thickness ratio of up to 200 % was first achieved through static loading with a total force of 90 N. A 55 mm displacement of the linkage mechanism transformed the model from NACA 0012 to NACA 0036. A total of 4 SMA wires (2 wires per bundle) provided the force required to actuate the test demonstrator up to half the morphing intended. The strain on the wires was limited to 3.5 % to allow a complete shape recovery. This thesis presents the methodology and the results obtained from designing building and testing the proposed wing-morphing model. Advisors/Committee Members: Oyadiji, Sunday.

Subjects/Keywords: Morphing wing; Adaptive wing; SMA; Variable thickness wing; Shape morphing; Smart materials

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

APA (6^th Edition):

El Ouardi, O. (2014). Design, Analysis And Testing Of An Aircraft Wing Model With Morphing Mechanism. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:237682

Chicago Manual of Style (16^th Edition):

El Ouardi, Othman. “Design, Analysis And Testing Of An Aircraft Wing Model With Morphing Mechanism.” 2014. Doctoral Dissertation, University of Manchester. Accessed January 17, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:237682.

MLA Handbook (7^th Edition):

El Ouardi, Othman. “Design, Analysis And Testing Of An Aircraft Wing Model With Morphing Mechanism.” 2014. Web. 17 Jan 2021.

Vancouver:

El Ouardi O. Design, Analysis And Testing Of An Aircraft Wing Model With Morphing Mechanism. [Internet] [Doctoral dissertation]. University of Manchester; 2014. [cited 2021 Jan 17]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:237682.

Council of Science Editors:

El Ouardi O. Design, Analysis And Testing Of An Aircraft Wing Model With Morphing Mechanism. [Doctoral Dissertation]. University of Manchester; 2014. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:237682

Arizona State University

5. Kirkman, Jeffrey Jordan. Transonic Flow Around Swept Wings: Revisiting Von Kármán’s Similarity Rule.

Degree: Aerospace Engineering, 2016, Arizona State University

URL: http://repository.asu.edu/items/38688

► Modern aircraft are expected to fly faster and more efficiently than their predecessors. To improve aerodynamic efficiency, designers must carefully consider and handle shock wave… (more)

Subjects/Keywords: Aerospace engineering; Aircraft Wing Sweep; Critical Pressure Coefficient; Shock Formation; Transonic Similarity Rule

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APA (6^th Edition):

Kirkman, J. J. (2016). Transonic Flow Around Swept Wings: Revisiting Von Kármán’s Similarity Rule. (Masters Thesis). Arizona State University. Retrieved from http://repository.asu.edu/items/38688

Chicago Manual of Style (16^th Edition):

Kirkman, Jeffrey Jordan. “Transonic Flow Around Swept Wings: Revisiting Von Kármán’s Similarity Rule.” 2016. Masters Thesis, Arizona State University. Accessed January 17, 2021. http://repository.asu.edu/items/38688.

MLA Handbook (7^th Edition):

Kirkman, Jeffrey Jordan. “Transonic Flow Around Swept Wings: Revisiting Von Kármán’s Similarity Rule.” 2016. Web. 17 Jan 2021.

Vancouver:

Kirkman JJ. Transonic Flow Around Swept Wings: Revisiting Von Kármán’s Similarity Rule. [Internet] [Masters thesis]. Arizona State University; 2016. [cited 2021 Jan 17]. Available from: http://repository.asu.edu/items/38688.

Council of Science Editors:

Kirkman JJ. Transonic Flow Around Swept Wings: Revisiting Von Kármán’s Similarity Rule. [Masters Thesis]. Arizona State University; 2016. Available from: http://repository.asu.edu/items/38688

6. Felício, João Miguel Inácio. Development and testing of a variable-spam morphing wing.

Degree: 2010, RCAAP

URL: http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3663

► The present work focuses on the development and validation of a variable-span morphing wing (VSW) to be fitted to a mini UAV. An electro-mechanical actuation… (more)

Subjects/Keywords: Aeronaves - Asa; Asa morphing; Aeronaves - Asa de envergadura variável; VSW (Variable Spam Wing); Variable spam wing

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APA (6^th Edition):

Felício, J. M. I. (2010). Development and testing of a variable-spam morphing wing. (Thesis). RCAAP. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3663

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Felício, João Miguel Inácio. “Development and testing of a variable-spam morphing wing.” 2010. Thesis, RCAAP. Accessed January 17, 2021. http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3663.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Felício, João Miguel Inácio. “Development and testing of a variable-spam morphing wing.” 2010. Web. 17 Jan 2021.

Vancouver:

Felício JMI. Development and testing of a variable-spam morphing wing. [Internet] [Thesis]. RCAAP; 2010. [cited 2021 Jan 17]. Available from: http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3663.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Felício JMI. Development and testing of a variable-spam morphing wing. [Thesis]. RCAAP; 2010. Available from: http://www.rcaap.pt/detail.jsp?id=oai:ubibliorum.ubi.pt:10400.6/3663

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Florida

7. Speer, Kelly. Dispersal of Bats in an Island System.

Degree: MS, Zoology - Biology, 2015, University of Florida

URL: https://ufdc.ufl.edu/UFE0049349

► Dispersal is a key variable in many fields of biology, including phylogenetics, epidemiology, and conservation. Dispersal can be difficult to quantify, requiring intensive fieldwork, thorough… (more)

Subjects/Keywords: Bats; Caves; Ecology; Microsatellites; Museums; Population estimates; Population genetics; Population structure; Species; Variable sweep wings; bats – dispersal; City of Gainesville ( local )

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APA (6^th Edition):

Speer, K. (2015). Dispersal of Bats in an Island System. (Masters Thesis). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0049349

Chicago Manual of Style (16^th Edition):

Speer, Kelly. “Dispersal of Bats in an Island System.” 2015. Masters Thesis, University of Florida. Accessed January 17, 2021. https://ufdc.ufl.edu/UFE0049349.

MLA Handbook (7^th Edition):

Speer, Kelly. “Dispersal of Bats in an Island System.” 2015. Web. 17 Jan 2021.

Vancouver:

Speer K. Dispersal of Bats in an Island System. [Internet] [Masters thesis]. University of Florida; 2015. [cited 2021 Jan 17]. Available from: https://ufdc.ufl.edu/UFE0049349.

Council of Science Editors:

Speer K. Dispersal of Bats in an Island System. [Masters Thesis]. University of Florida; 2015. Available from: https://ufdc.ufl.edu/UFE0049349

Virginia Tech

8. Mallik, Wrik. Aeroelastic Analysis of Truss-Braced Wing Aircraft: Applications for Multidisciplinary Design Optimization.

Degree: PhD, Aerospace Engineering, 2016, Virginia Tech

URL: http://hdl.handle.net/10919/71650

► This study highlights the aeroelastic behavior of very flexible truss-braced wing (TBW) aircraft designs obtained through a multidisciplinary design optimization (MDO) framework. Several improvements to… (more)

▼ This study highlights the aeroelastic behavior of very flexible truss-braced wing (TBW) aircraft designs obtained through a multidisciplinary design optimization (MDO) framework. Several improvements to previous analysis methods were developed and validated. Firstly, a flutter constraint was developed and the effects of the constraint on the MDO of TBW transport aircraft for both medium-range and long-range missions were studied while minimizing the take-off gross weight (TOGW) and the fuel burn as the objective functions. Results show that when the flutter constraint is applied at 1.15 times the dive speed, it imposes a 1.5% penalty on the take-off weight and a 5% penalty on the fuel consumption while minimizing these two objective functions for the medium-range mission. For the long-range mission, the penalties imposed by the similar constraint on the minimum TOGW and minimum fuel burn designs are 3.5% and 7.5%, respectively. Importantly, the resulting TBW designs are still superior to equivalent cantilever designs for both of the missions as they have both lower TOGW and fuel burn. However, a relaxed flutter constraint applied at 1.05 times the dive speed can restrict the penalty on the TOGW to only 0.3% and that on the fuel burn to 2% for minimizing both the objectives, for the medium-range mission. For the long-range mission, a similar relaxed constraint can reduce the penalty on fuel burn to 2.9%. These observations suggest further investigation into active flutter suppression mechanisms for the TBW aircraft to further reduce either the TOGW or the fuel burn. Secondly, the effects of a variable-geometry raked wingtip (VGRWT) on the maneuverability and aeroelastic behavior of passenger aircraft with very flexible truss-braced wings (TBW) were investigated. These TBW designs obtained from the MDO environment while minimizing fuel burn resemble a Boeing 777-200 Long Range (LR) aircraft both in terms of flight mission and aircraft configuration. The VGRWT can sweep forward and aft relative to the wing with the aid of a Novel Control Effector (NCE) mechanism. Results show that the VGRWT can be swept judiciously to alter the bending-torsion coupling and the movement of the center of pressure of wing. Such behavior of the VGRWT is applied to both achieve the required roll control as well as to increase flutter speed, and thus, enable the operation of TBW configurations which have up to 10% lower fuel burn than comparable optimized cantilever wing designs. Finally, a transonic aeroelastic analysis tool was developed which can be used for conceptual design in an MDO environment. Routine transonic aeroelastic analysis require expensive CFD simulations, hence they cannot be performed in an MDO environment. The present approach utilizes the results of a companion study of CFD simulations performed offline for the steady Reynolds Averaged Navier Stokes equations for a variety of airfoil parameters. The CFD results are used to develop a response surface which can be used in the MDO environment to perform a… Advisors/Committee Members: Kapania, Rakesh K. (committeechair), Schetz, Joseph A. (committee member), Patil, Mayuresh J. (committee member), Roy, Christopher John (committee member).

Subjects/Keywords: Aeroelasticity; Multidisciplinary Design Optimization; Truss-Braced Wing Aircraft; Variable Geometry Raked Wingtip; State-space Aerodynamics

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

APA (6^th Edition):

Mallik, W. (2016). Aeroelastic Analysis of Truss-Braced Wing Aircraft: Applications for Multidisciplinary Design Optimization. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/71650

Chicago Manual of Style (16^th Edition):

Mallik, Wrik. “Aeroelastic Analysis of Truss-Braced Wing Aircraft: Applications for Multidisciplinary Design Optimization.” 2016. Doctoral Dissertation, Virginia Tech. Accessed January 17, 2021. http://hdl.handle.net/10919/71650.

MLA Handbook (7^th Edition):

Mallik, Wrik. “Aeroelastic Analysis of Truss-Braced Wing Aircraft: Applications for Multidisciplinary Design Optimization.” 2016. Web. 17 Jan 2021.

Vancouver:

Mallik W. Aeroelastic Analysis of Truss-Braced Wing Aircraft: Applications for Multidisciplinary Design Optimization. [Internet] [Doctoral dissertation]. Virginia Tech; 2016. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/10919/71650.

Council of Science Editors:

Mallik W. Aeroelastic Analysis of Truss-Braced Wing Aircraft: Applications for Multidisciplinary Design Optimization. [Doctoral Dissertation]. Virginia Tech; 2016. Available from: http://hdl.handle.net/10919/71650

University of Dayton

9. Zientarski, Lauren Ann. Wind Tunnel Testing of a Variable Camber Compliant Wing with a Unique Dual Load Cell Test Fixture.

Degree: MS(M.S.), Aerospace Engineering, 2015, University of Dayton

URL: http://rave.ohiolink.edu/etdc/view?acc_num=dayton1448893315

► This thesis describes the design, setup, and testing of a unique mounting fixture built for the Variable Camber Compliant Wing developed by the U.S. Air… (more)

Subjects/Keywords: Aerospace Engineering; Engineering; Variable Camber Compliant Wing; Dual Load Cell; Test Fixture Validation; Calibration Loading

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

APA (6^th Edition):

Zientarski, L. A. (2015). Wind Tunnel Testing of a Variable Camber Compliant Wing with a Unique Dual Load Cell Test Fixture. (Masters Thesis). University of Dayton. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=dayton1448893315

Chicago Manual of Style (16^th Edition):

Zientarski, Lauren Ann. “Wind Tunnel Testing of a Variable Camber Compliant Wing with a Unique Dual Load Cell Test Fixture.” 2015. Masters Thesis, University of Dayton. Accessed January 17, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1448893315.

MLA Handbook (7^th Edition):

Zientarski, Lauren Ann. “Wind Tunnel Testing of a Variable Camber Compliant Wing with a Unique Dual Load Cell Test Fixture.” 2015. Web. 17 Jan 2021.

Vancouver:

Zientarski LA. Wind Tunnel Testing of a Variable Camber Compliant Wing with a Unique Dual Load Cell Test Fixture. [Internet] [Masters thesis]. University of Dayton; 2015. [cited 2021 Jan 17]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=dayton1448893315.

Council of Science Editors:

Zientarski LA. Wind Tunnel Testing of a Variable Camber Compliant Wing with a Unique Dual Load Cell Test Fixture. [Masters Thesis]. University of Dayton; 2015. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=dayton1448893315

10. Boulamatsis, Achilles. Active control of wind turbines through varying blade tip sweep.

Degree: 2017, University of Thessaly (UTH); Πανεπιστήμιο Θεσσαλίας

URL: http://hdl.handle.net/10442/hedi/40592

►

In this research work an introduction to an innovative control method, concerning horizontal axis wind turbines, is presented. The concept refers to variable tip swept… (more)

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In this research work an introduction to an innovative control method, concerning horizontal axis wind turbines, is presented. The concept refers to variable tip swept rotorblades, that have the ability to pivot collectively aft, (in-plane movement) about an axis located at the blade tips. The swept tip can be either part of the main blade with an internal mechanism or an added surface (add-on) to the blades. The idea of this active control feature is to increase power production at specific operating areas and reduce fatigue loads and extreme blade loads during a wind gust passage through small sweep angle variations in the tip area. The investigation is carried out with a modified Blade Element Momentum (BEM) model that takes into account variable tip swept rotor blades and the modifications are based on results from a lifting line theory based model. The latter model was also compared to Computational Fluid Dynamics (CFD) results and speed optimized with the use of CUDA platform before it was used as reference for the modified BEM model. The simulations refer to the 5MW NREL reference wind turbine that incorporates a suitable controller and the first results show beneficial behavior in all of the investigated areas.

Σε αυτή την ερευνητική εργασία παρουσιάζεται ένας πρωτότυπος τρόπος ελέγχου των ανεμογεννητριών οριζόντιου άξονα. Η ιδέα αυτή, αναφέρεται σε πτερύγια ανεμογεννήτριας μεταβλητής γωνίας οπισθόκλισης των ακροπτερύγιων τους, τα οποία έχουν την ικανότητα να περιστρέφονται συλλογικά (κίνηση εντός επιπέδου περιστροφής του ρότορα) γύρω από έναν άξονα που βρίσκεται επάνω στα πτερυγία. Το οπισθοκλινές ακροπτερύγιο μπορεί να είναι τμήμα του υπάρχοντος πτερυγίου με ενσωματωμένο μηχανισμό ή προέκταση αυτού. Η ιδέα αυτού του πρωτότυπου τρόπου ενεργού ελέγχου, έχει ως σκοπό την αύξηση της παραγώμενης ενέργειας σε συγκεκριμένες περιοχές λειτουργίας, τη μείωση των φορτίων κόπωσης των πτερυγίων καθώς και των υψηλών φορτίων κατά τη διάρκεια μίας ριπής ανέμου που διέρχεται από την ανεμογεννήτρια, μέσω της μεταβολής της γωνίας οπισθόκλισης των ακροπτερυγίων του ρότορα. Η έρευνα διεξάγεται με ένα κατάλληλα τροποποιημένο μοντέλο βασισμένο στη θεωρία Blade Element Momentum (BEM) ώστε να λαμβάνεται υπόψη η επίδραση του οπισθοκλινούς ακροπτερυγίου και η τροποποίηση αυτή βασίστηκε στα αποτελέσματα που προκύπτουν από ένα αντίστοιχο μοντέλο βασισμένο στη θεωρία Lifting Line. Τα αποτελέσματα από το τελευταίο μοντέλο συγκρίθηκαν επίσης με αποτελέσματα που προέκυψαν από αντίστοιχα μοντέλα υπολογιστικής ρευστομηχανικής (CFD) και επιπλέον έγινε προσπάθεια επιτάχυνσης των υπολογισμών (με χρήση CUDA platform) που εκτελούνται εντός του μοντέλου (Lifting Line) πριν αυτό χρησιμοποιηθεί ως σημείο αναφοράς για την τροποποίηση του μοντέλου BEM. Οι προσομοιώσεις αφορούν την 5MW NREL ανεμογεννήτρια αναφοράς που ενσωματώνει ένα κατάλληλο ελεγκτή και τα πρώτα αποτελέσματα δείχνουν ωφέλιμη συμπεριφορά σε όλες τους τομείς που μελετήθηκε η επίδρασή του.

Subjects/Keywords: Ανεμογεννήτρια; Wind turbine; Sweep

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

APA (6^th Edition):

Boulamatsis, A. (2017). Active control of wind turbines through varying blade tip sweep. (Thesis). University of Thessaly (UTH); Πανεπιστήμιο Θεσσαλίας. Retrieved from http://hdl.handle.net/10442/hedi/40592

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Boulamatsis, Achilles. “Active control of wind turbines through varying blade tip sweep.” 2017. Thesis, University of Thessaly (UTH); Πανεπιστήμιο Θεσσαλίας. Accessed January 17, 2021. http://hdl.handle.net/10442/hedi/40592.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Boulamatsis, Achilles. “Active control of wind turbines through varying blade tip sweep.” 2017. Web. 17 Jan 2021.

Vancouver:

Boulamatsis A. Active control of wind turbines through varying blade tip sweep. [Internet] [Thesis]. University of Thessaly (UTH); Πανεπιστήμιο Θεσσαλίας; 2017. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/10442/hedi/40592.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Boulamatsis A. Active control of wind turbines through varying blade tip sweep. [Thesis]. University of Thessaly (UTH); Πανεπιστήμιο Θεσσαλίας; 2017. Available from: http://hdl.handle.net/10442/hedi/40592

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

11. Camarinha Fujiwara, Gustavo. Design of 3D swept wing hybrid models for icing wind tunnel tests.

Degree: MS, 4048, 2015, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/72880

► The study of aircraft icing is critical to ensure the safety of any aircraft that might experience icing conditions in flight, including general, commercial, and… (more)

▼ The study of aircraft icing is critical to ensure the safety of any aircraft that might experience icing conditions in flight, including general, commercial, and military aviation. The certification of modern commercial transports requires manufacturers to demonstrate that these aircraft can safely operate during icing conditions through a set of flight tests, consistent with the standards set forth by the Federal Aviation Administration. This is often expensive and challenging to find the appropriate icing test conditions. Thus, both computational methods and icing wind tunnel experiments are utilized during the design and certification of aircraft ice-protection systems to provide a controlled and repeatable environment to mitigate risks, reduce costs, and validate the existing computational icing tools. However, the existing icing wind tunnel facilities cannot accommodate large wings such as those found on modern commercial aircraft without being dramatically scaled. Two methods of scaling exist. The first geometrically scales the entire geometry to fit inside the tunnel test section and then scales the icing conditions to obtain icing similitude. The second maintains the full-scale leading edge of the reference geometry and replaces the aft section with a truncated trailing edge that produces a similar flowfield around the leading edge with a significantly shorter chord, reducing model size and tunnel blockage. This type of model is referred to as a hybrid and its biggest advantage lies in the fact that it is designed to produce full-scale ice shapes, while reducing or even eliminating the need for icing scaling. While a design method for a straight, untapered hybrid wing is well documented and there is a broad set of experimental data available, the design of a swept, hybrid wing lacks both a design method and experimental data. This thesis established a design method for large hybrid swept wings that reproduce full-scale ice accretions through icing wind tunnel tests. The design method was broken down in two steps: 1) A 2D hybrid airfoil design, and 2) A 3D hybrid swept wing design. Multiple existing computational tools were employed and several parametric studies performed. It was shown, in 2D, that matching the stagnation point location on the leading edge of the hybrid airfoil had a first-order impact on matching the full-scale ice shape, while matching the suction peak magnitude and location had a second-order effect. The closer to the leading edge lift was generated for a given hybrid design, the less total load was required to reach the same stagnation point location. As an implication, more front-loaded airfoils required less lift than more aft-loaded ones to reach the same stagnation point location on a hybrid airfoil. More front load also increased the risk of flow separation near the leading edge, while more aft load increased the risk of separation near the trailing edge. Finally, higher hybrid scale factors were shown to increase the risk of flow separation. In 3D, sweep angle was… Advisors/Committee Members: Bragg, Michael B. (advisor).

Subjects/Keywords: Aerodynamics; aircraft icing; wind tunnel; icing; ice shape; Accretion; hybrid; sweep; swept; wing; computational fluid dynamics (CFD); aircraft certification; wing design

…a transonic wing having a quarter-chord sweep angle of 35◦ . The supercritical wing was… …designed utilizing the stations in the normal direction, applying simple sweep wing theory, as… …to extrude a rectangular wing of the same leading-edge sweep angle, and then takes the… …1.2 Previous Work . . . . . . . . . . . . . . . . . . . . . 1.3 Large-Scale Swept-Wing Ice… …Sidewalls . . . . . . . . . 4.2.2 Effect of Sweep Angle . . . . . . . . . . . . . . . 4.2.3 Effect…

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APA (6^th Edition):

Camarinha Fujiwara, G. (2015). Design of 3D swept wing hybrid models for icing wind tunnel tests. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/72880

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Camarinha Fujiwara, Gustavo. “Design of 3D swept wing hybrid models for icing wind tunnel tests.” 2015. Thesis, University of Illinois – Urbana-Champaign. Accessed January 17, 2021. http://hdl.handle.net/2142/72880.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Camarinha Fujiwara, Gustavo. “Design of 3D swept wing hybrid models for icing wind tunnel tests.” 2015. Web. 17 Jan 2021.

Vancouver:

Camarinha Fujiwara G. Design of 3D swept wing hybrid models for icing wind tunnel tests. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2015. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/2142/72880.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Camarinha Fujiwara G. Design of 3D swept wing hybrid models for icing wind tunnel tests. [Thesis]. University of Illinois – Urbana-Champaign; 2015. Available from: http://hdl.handle.net/2142/72880

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

12. Wiberg, Brock. Large-scale swept-wing ice accretion modeling in the NASA Glenn Icing Research Tunnel using LEWICE3D.

Degree: MS, 4048, 2014, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/46609

► The study of aircraft icing is necessary to ensure the safety of commercial, military, and general aviation aircraft. The certification of modern commercial transports requires… (more)

▼ The study of aircraft icing is necessary to ensure the safety of commercial, military, and general aviation aircraft. The certification of modern commercial transports requires manufacturers to demonstrate that these aircraft can safely operate during icing conditions consistent with the standards set forth by the Federal Aviation Administration (FAA). While some of these tests are performed on actual aircraft in flight, this is often very expensive and does not provide an adequately controlled matrix of test conditions. Computational tools are used throughout the design and certification of anti-ice systems. However, computational methods alone are not sufficient for aircraft certification. Icing wind tunnels are used for aircraft certification to reduce costs, provide a controlled test matrix of conditions, and validate computational icing tools. The size of aircraft models that can be tested in icing wind tunnels is limited by the size and capability of existing facilities. Large wings, such as those found on modern narrow and wide-body commercial transports, cannot fit in existing test sections without being dramatically scaled. Two methods of scaling exist. The first involves geometrically scaling a section of the reference wing to fit inside the tunnel test section and then scaling the icing conditions in order to maintain icing similitude. The second method maintains the full-scale leading edge of the reference geometry but replaces the aft section of the wing with a tail that is designed to produce similar flow around the leading edge but with a considerably shorter chord length, reducing model size and blockage. This type of model is called a hybrid and is used to generate full-scale ice shapes so that, in the simplest cases, no icing scaling is necessary. However, the methods can be combined so that the hybrid model design is used to maintain geometric similitude while icing scaling is employed to account for differences in pressure, velocity, or other conditions. Modern commercial transport aircraft have large, swept wings. While a broad set of experimental data exist in the literature for airfoil and straight wing icing, there is a distinct lack of data for large, swept wings. Such data is needed in order to better understand the 3D icing physics on swept wings and to allow computational tools to be developed and validated for 3D ice features such as scallops. In this thesis, computational tools were used to better understand the flow over a large-scale, swept-wing, hybrid model mounted vertically in the NASA Glenn Icing Research Tunnel (IRT). Fluent, a commercial CFD code, was used to calculate flows around the flapped-hybrid model in the IRT, mounted with the root at the floor and the tip at the ceiling of the test section. Inviscid analysis reveals that the upwash ahead of the model causes the local lift coefficient to increase significantly across the swept model due to the effect of the floor and ceiling. This change in spanwise loading is shown to move the attachment line location farther… Advisors/Committee Members: Bragg, Michael B. (advisor).

Subjects/Keywords: aircraft icing; icing; ice shape; Accretion; sweep; swept; wing; computational fluid dynamics (CFD); aircraft certification; hybrid; similitude

…2.2.2 Simple Sweep Theory . . . . . . . . . . . . . . . . 2.2.3 Wing Model Design… …sweep angle λ = wing taper ratio µ = dynamic viscosity ν = kinematic viscosity ρ… …chord sweep of 35 deg. The supercritical wing was designed for a cruise Mach number of M… …having a quarter-chord sweep of Λ = 35 deg. (see Table 1.1). The supercritical wing… …1.2 Previous Work . . . . . . . . . . . . . . . . . . . . . 1.3 Large-Scale Swept-Wing Ice…

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APA (6^th Edition):

Wiberg, B. (2014). Large-scale swept-wing ice accretion modeling in the NASA Glenn Icing Research Tunnel using LEWICE3D. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/46609

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wiberg, Brock. “Large-scale swept-wing ice accretion modeling in the NASA Glenn Icing Research Tunnel using LEWICE3D.” 2014. Thesis, University of Illinois – Urbana-Champaign. Accessed January 17, 2021. http://hdl.handle.net/2142/46609.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wiberg, Brock. “Large-scale swept-wing ice accretion modeling in the NASA Glenn Icing Research Tunnel using LEWICE3D.” 2014. Web. 17 Jan 2021.

Vancouver:

Wiberg B. Large-scale swept-wing ice accretion modeling in the NASA Glenn Icing Research Tunnel using LEWICE3D. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2014. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/2142/46609.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wiberg B. Large-scale swept-wing ice accretion modeling in the NASA Glenn Icing Research Tunnel using LEWICE3D. [Thesis]. University of Illinois – Urbana-Champaign; 2014. Available from: http://hdl.handle.net/2142/46609

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Penn State University

13. Harris, Alexandre. Improved methods for detecting, quantifying, and classifying genetic diversity in natural populations.

Degree: 2020, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/17977amh522

► The field of population genetics has made impressive advances over the two decades since the sequencing of the human genome, and specifically in the last… (more)

▼ The field of population genetics has made impressive advances over the two decades since the sequencing of the human genome, and specifically in the last decade since the advent of cost-effective high-throughput whole-genome sequencing. These advances have served to highlight the need for new statistical methods suitable for interrogating signatures of genetic diversity arising from the massive amounts of data being produced, while accounting for samples that deviate from the ideal of large sample size, phased haplotype data, and only outbred and unrelated individuals in the sample. To this end, I introduce four methods specifically designed to address the aforementioned sampling deviations, thoroughly explore their properties, and demonstrate their suitability for use, especially with data for non-model organisms. The first of these is an unbiased estimator of expected heterozygosity that accounts for the downward bias introduced by sampling related or inbred individuals. This estimator, H~BLUE, outperforms all others that we tested and has downstream applications for the computation of quantities that depend upon it. Next is an extension to the H12 statistic of Garud et al. (2015), which detects hard and soft selective sweeps, applied to unphased multilocus genotype (MLG) data. This new statistic, G123, maintains performance on par with that of H12, but is ideal for use with non-model organisms, for which phased data may not be available. Third, I develop a further extension to H12, termed SS-H12, which I use to identify selective sweeps shared between two or more sampled study populations. SS-H12 is unique because it can distinguish between sweeps that are shared through common ancestry from sweeps that are the result of independent convergent events affecting a common locus. As with H12, I extend this approach to MLG data as SS-G123 and find that it once again works well to characterize sweeps. Finally, I derive a maximum likelihood-based T statistic that also detects selective sweeps from a distortion in the haplotype frequency spectrum, but has more power than H12, representing the next step in fast and efficient characterization of selective sweeps which also can use the spectrum of unphased MLGs as input. I expect that these new tools will be especially useful to researchers who work with data that are unsuitable for analysis with modern computationally intensive methods, which are often incompatible with non-ideal data types, while maintaining excellent performance comparable to more sophisticated approaches. Advisors/Committee Members: Michael DeGiorgio, Dissertation Advisor/Co-Advisor, Stephen Wade Schaeffer, Committee Chair/Co-Chair, George H Perry, Committee Member, Michael DeGiorgio, Committee Chair/Co-Chair, Paul Medvedev, Outside Member, Melissa Rolls, Program Head/Chair, Stephen Wade Schaeffer, Dissertation Advisor/Co-Advisor.

Subjects/Keywords: Unbiased estimator; Haplotype; Multilocus genotype; Selective sweep; Maximum likelihood; Soft sweep

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

APA (6^th Edition):

Harris, A. (2020). Improved methods for detecting, quantifying, and classifying genetic diversity in natural populations. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/17977amh522

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Harris, Alexandre. “Improved methods for detecting, quantifying, and classifying genetic diversity in natural populations.” 2020. Thesis, Penn State University. Accessed January 17, 2021. https://submit-etda.libraries.psu.edu/catalog/17977amh522.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Harris, Alexandre. “Improved methods for detecting, quantifying, and classifying genetic diversity in natural populations.” 2020. Web. 17 Jan 2021.

Vancouver:

Harris A. Improved methods for detecting, quantifying, and classifying genetic diversity in natural populations. [Internet] [Thesis]. Penn State University; 2020. [cited 2021 Jan 17]. Available from: https://submit-etda.libraries.psu.edu/catalog/17977amh522.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Harris A. Improved methods for detecting, quantifying, and classifying genetic diversity in natural populations. [Thesis]. Penn State University; 2020. Available from: https://submit-etda.libraries.psu.edu/catalog/17977amh522

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Alberta

14. Urbissinova, Tolkynay. Experimental investigation of the effect of elasticity on the sweep efficiency in viscoelastic polymer flooding operations.

Degree: MS, Department of Civil and Environmental Engineering, 2010, University of Alberta

URL: https://era.library.ualberta.ca/files/h702q654f

► This study aims to investigate the effect of elastic properties of viscoelastic polymer solutions on the microscopic sweep efficiency in enhanced oil recovery (EOR) operations.… (more)

Subjects/Keywords: sweep efficiency; viscoelastic polymer flooding; elasticity

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APA (6^th Edition):

Urbissinova, T. (2010). Experimental investigation of the effect of elasticity on the sweep efficiency in viscoelastic polymer flooding operations. (Masters Thesis). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/h702q654f

Chicago Manual of Style (16^th Edition):

Urbissinova, Tolkynay. “Experimental investigation of the effect of elasticity on the sweep efficiency in viscoelastic polymer flooding operations.” 2010. Masters Thesis, University of Alberta. Accessed January 17, 2021. https://era.library.ualberta.ca/files/h702q654f.

MLA Handbook (7^th Edition):

Urbissinova, Tolkynay. “Experimental investigation of the effect of elasticity on the sweep efficiency in viscoelastic polymer flooding operations.” 2010. Web. 17 Jan 2021.

Vancouver:

Urbissinova T. Experimental investigation of the effect of elasticity on the sweep efficiency in viscoelastic polymer flooding operations. [Internet] [Masters thesis]. University of Alberta; 2010. [cited 2021 Jan 17]. Available from: https://era.library.ualberta.ca/files/h702q654f.

Council of Science Editors:

Urbissinova T. Experimental investigation of the effect of elasticity on the sweep efficiency in viscoelastic polymer flooding operations. [Masters Thesis]. University of Alberta; 2010. Available from: https://era.library.ualberta.ca/files/h702q654f

Delft University of Technology

15. Sulistyo, Adhitomo (author). Injection of Water above Gas for Improved Sweep in Gas EOR: Non-uniform Injection and Sweep.

Degree: 2017, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:7c2ddae2-257e-4693-a47f-b2ba72c7a7d5

► One proposed method to delay the onset of gravity segregation between water and gas in enhanced oil and gas projects and extend the period of… (more)

▼ One proposed method to delay the onset of gravity segregation between water and gas in enhanced oil and gas projects and extend the period of effective macroscopic sweep in “SWAG” is by separating the injection wells into two parallel horizontal wells (Stone, 2004). In this “modified SWAG”, the water injection well is aligned at a distance above the gas injection well, and both water and gas are pumped simultaneously to displace the reservoir fluids. The significant density difference between the fluids and the ensuing counter-direction flow impede the segregation process. Initially Rossen et al. (2007) investigated the effectiveness of the technique based on 2D modelling and found that it increased the fluid segregation length. Van der Bol (2007) and Jamshidnezhad et al. (2010) broadened the scope of study and observed a non-uniform gas injection profile and volumetric sweep in 3D. Injection instability occurred in most of the simulation cases, despite the assumption of an ideally homogenous reservoir in the model. Mahalle (2013) identified several factors that triggers instability such as gas saturation and relative permeability behaviors in adjacent grid blocks. Since the instability was found to originate in the near-wellbore region, local grid refinement was applied along the entire length of the horizontal well, with more uniform gas-injection profile observed. Using a different reservoir simulator, Ranjan (2015) extended the previous study by checking again the effect of local grid refinement. The result, however, contradicts with the preceding finding. Grid refinement near the injection well did not improve stability in Ranjan’s study. The author also checked the effect of gas injection rate on the non-uniformity. Again, contradictory results were observed. While Ranjan reported that doubling the gas injection rate promotes non-uniform behavior, the earlier study obtained the opposite outcome. This thesis extends the previous studies by examining other parameters that may influence non-uniformity. We developed a method to quantify non-uniformity by calculating the coefficient of variation and max-min ratios for gas injection rate along the well. We looked at the effect of changes in well placement, reservoir properties, reservoir boundaries, reservoir fluids and operating constraints. We also fundamentally modified how the perturbation is applied along the gas-injection well by altering the skin factor while maintaining constant permeability. Results show that the type of perturbation significantly effects the non-uniformity of gas injection. We believe that perturbing permeability promotes the uniformity of gas-injection rate because of flow to neighboring grid blocks, and thereby more simulations are seen to be uniform compared the results with perturbation in skin factor. The results from this study suggests that non-uniformity is associated to the feedback between gas injection rate, water saturation and gas relative permeability, which is shown by the gas injection rate to vary more… Advisors/Committee Members: Hussain, Ahmed (mentor), Rossen, Bill (graduation committee), Delft University of Technology (degree granting institution).

Subjects/Keywords: reservoir simulation; sweep efficiency; non-uniform injection

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

APA (6^th Edition):

Sulistyo, A. (. (2017). Injection of Water above Gas for Improved Sweep in Gas EOR: Non-uniform Injection and Sweep. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:7c2ddae2-257e-4693-a47f-b2ba72c7a7d5

Chicago Manual of Style (16^th Edition):

Sulistyo, Adhitomo (author). “Injection of Water above Gas for Improved Sweep in Gas EOR: Non-uniform Injection and Sweep.” 2017. Masters Thesis, Delft University of Technology. Accessed January 17, 2021. http://resolver.tudelft.nl/uuid:7c2ddae2-257e-4693-a47f-b2ba72c7a7d5.

MLA Handbook (7^th Edition):

Sulistyo, Adhitomo (author). “Injection of Water above Gas for Improved Sweep in Gas EOR: Non-uniform Injection and Sweep.” 2017. Web. 17 Jan 2021.

Vancouver:

Sulistyo A(. Injection of Water above Gas for Improved Sweep in Gas EOR: Non-uniform Injection and Sweep. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Jan 17]. Available from: http://resolver.tudelft.nl/uuid:7c2ddae2-257e-4693-a47f-b2ba72c7a7d5.

Council of Science Editors:

Sulistyo A(. Injection of Water above Gas for Improved Sweep in Gas EOR: Non-uniform Injection and Sweep. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:7c2ddae2-257e-4693-a47f-b2ba72c7a7d5

16. Chuang, Jason C. Variable Speed Flapping Wing Micro Air Vehicle using a Continuous Variable Transmission Design.

Degree: MSEgr, Mechanical Engineering, 2014, Wright State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=wright1401813452

► Flapping wing micro air vehicles (FWMAV) have very unique flight mechanics in two-wing orientation. Many challenges arise with two wing configuration: lift production, design construction,… (more)

Subjects/Keywords: Aerospace Engineering; MAV; micro air vehicle, CVT, continuous variable transmission; flapping wing micro air vehicle; FWMAV

…method of variable flapping in MAVs is using two motors to control each wing independently… …39 x CHAPTER 1 INTRODUCTION 1.1 Flapping Wing Micro Air Vehicle Flapping Wing Micro Air… …inspired dragonfly lead to the development of the Wright State’s Four Wing Flapper, Delfly’s… …Delfly I and II. These four wing FWMAVs use the flight mechanism of a two-fixed wing structure… …their two wing designs. In evolution their second wing was adapted into halters, which are…

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APA (6^th Edition):

Chuang, J. C. (2014). Variable Speed Flapping Wing Micro Air Vehicle using a Continuous Variable Transmission Design. (Masters Thesis). Wright State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=wright1401813452

Chicago Manual of Style (16^th Edition):

Chuang, Jason C. “Variable Speed Flapping Wing Micro Air Vehicle using a Continuous Variable Transmission Design.” 2014. Masters Thesis, Wright State University. Accessed January 17, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wright1401813452.

MLA Handbook (7^th Edition):

Chuang, Jason C. “Variable Speed Flapping Wing Micro Air Vehicle using a Continuous Variable Transmission Design.” 2014. Web. 17 Jan 2021.

Vancouver:

Chuang JC. Variable Speed Flapping Wing Micro Air Vehicle using a Continuous Variable Transmission Design. [Internet] [Masters thesis]. Wright State University; 2014. [cited 2021 Jan 17]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=wright1401813452.

Council of Science Editors:

Chuang JC. Variable Speed Flapping Wing Micro Air Vehicle using a Continuous Variable Transmission Design. [Masters Thesis]. Wright State University; 2014. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=wright1401813452

Virginia Tech

17. Natarajan, Anand. Aeroelasticity of Morphing Wings Using Neural Networks.

Degree: PhD, Aerospace and Ocean Engineering, 2002, Virginia Tech

URL: http://hdl.handle.net/10919/28267

► In this dissertation, neural networks are designed to effectively model static non-linear aeroelastic problems in adaptive structures and linear dynamic aeroelastic systems with time varying… (more)

▼ In this dissertation, neural networks are designed to effectively model static non-linear aeroelastic problems in adaptive structures and linear dynamic aeroelastic systems with time varying stiffness. The use of adaptive materials in aircraft wings allows for the change of the contour or the configuration of a wing (morphing) in flight. The use of smart materials, to accomplish these deformations, can imply that the stiffness of the wing with a morphing contour changes as the contour changes. For a rapidly oscillating body in a fluid field, continuously adapting structural parameters may render the wing to behave as a time variant system. Even the internal spars/ribs of the aircraft wing which define the wing stiffness can be made adaptive, that is, their stiffness can be made to vary with time. The immediate effect on the structural dynamics of the wing, is that, the wing motion is governed by a differential equation with time varying coefficients. The study of this concept of a time varying torsional stiffness, made possible by the use of active materials and adaptive spars, in the dynamic aeroelastic behavior of an adaptable airfoil is performed here. A time marching technique is developed for solving linear structural dynamic problems with time-varying parameters. This time-marching technique borrows from the concept of Time-Finite Elements in the sense that for each time interval considered in the time-marching, an analytical solution is obtained. The analytical solution for each time interval is in the form of a matrix exponential and hence this technique is termed as Matrix Exponential time marching. Using this time marching technique, Artificial Neural Networks can be trained to represent the dynamic behavior of any linearly time varying system. In order to extend this methodology to dynamic aeroelasticity, it is also necessary to model the unsteady aerodynamic loads over an airfoil. Accordingly, an unsteady aerodynamic panel method is developed using a distributed set of doublet panels over the surface of the airfoil and along its wake. When the aerodynamic loads predicted by this panel method are made available to the Matrix Exponential time marching scheme for every time interval, a dynamic aeroelastic solver for a time varying aeroelastic system is obtained. This solver is now used to train an array of neural networks to represent the response of this two dimensional aeroelastic system with a time varying torsional stiffness. These neural networks are developed into a control system for flutter suppression. Another type of aeroelastic problem of an adaptive structure that is investigated here is the shape control of an adaptive bump situated on the leading edge of an airfoil. Such a bump is useful in achieving flow separation control for lateral directional maneuverability of the aircraft. Since actuators are being used to create this bump on the wing surface, the energy required to do so needs to be minimized. The adverse pressure drag as a result of this bump needs to be controlled so that the loss… Advisors/Committee Members: Kapania, Rakesh K. (committeechair), Librescu, Liviu (committee member), Inman, Daniel J. (committee member), Mason, William H. (committee member), Johnson, Eric R. (committee member).

Subjects/Keywords: Time Varying Systems; Morphing Wings; Aeroelasticity; Adaptable Bump; Variable Stiffness Wing; Neural Networks; Flutter

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

APA (6^th Edition):

Natarajan, A. (2002). Aeroelasticity of Morphing Wings Using Neural Networks. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/28267

Chicago Manual of Style (16^th Edition):

Natarajan, Anand. “Aeroelasticity of Morphing Wings Using Neural Networks.” 2002. Doctoral Dissertation, Virginia Tech. Accessed January 17, 2021. http://hdl.handle.net/10919/28267.

MLA Handbook (7^th Edition):

Natarajan, Anand. “Aeroelasticity of Morphing Wings Using Neural Networks.” 2002. Web. 17 Jan 2021.

Vancouver:

Natarajan A. Aeroelasticity of Morphing Wings Using Neural Networks. [Internet] [Doctoral dissertation]. Virginia Tech; 2002. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/10919/28267.

Council of Science Editors:

Natarajan A. Aeroelasticity of Morphing Wings Using Neural Networks. [Doctoral Dissertation]. Virginia Tech; 2002. Available from: http://hdl.handle.net/10919/28267

Texas A&M University

18. Cooper, Jacob. Multi-Resolution Simulations of Delta/Diamond Wing Aerodynamics.

Degree: PhD, Aerospace Engineering, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/153426

► This dissertation investigates high angle of attack delta wing flow at multiple resolutions of turbulence closure. The work is divided into four studies. The objectives… (more)

▼ This dissertation investigates high angle of attack delta wing flow at multiple resolutions of turbulence closure. The work is divided into four studies. The objectives of each study are: (i) to identify the limits of RANS modeling, (ii) explore the challenges of applying the PANS model to the delta wing flow, (iii) identify the appropriate resolution required to capture specific flow features, and (iv) determine the physical differences between sharp and round leading edge separation. The outcomes from each of these studies are as follows. Steady-state RANS modeling is shown to be adequate for low and moderate angles of attack, except in regions near the point of primary vortex separation. At low Reynolds number the vortex structure on the forward portion of the wing is mostly laminar and must be fully resolved by the grid in order to capture the physics in the aft region. Also at low Reynolds numbers, it is shown that lower resolution simulations perform adequately in capturing important integral flow features such as pressure coefficient and the locations of the vortex separation and attachment lines. High resolution simulations of low Reynolds number flow do resolve more subtle flow features that do not significantly affect the aerodynamic characteristics. The principle advantages of high resolution simulations are most evident at high Reynolds numbers and high angles of attack. The relationship between scale resolution and observed flow features is established. The simulations establish the key flow feature differences between round and sharp leading edge wing at different length scales of motion. Features of interest are the intensity of the vortex structure, the levels of turbulence, surface streamline patterns, and surface pressure coefficient. Differences between the delta and diamond wing shapes are also identified. Advisors/Committee Members: Girimaji, Sharath S (advisor), Cizmas, Paul (committee member), Donzis, Diego (committee member), Chen, Hamn-Ching (committee member).

Subjects/Keywords: delta wing; diamond wing; turbulence model; PANS

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

APA (6^th Edition):

Cooper, J. (2014). Multi-Resolution Simulations of Delta/Diamond Wing Aerodynamics. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153426

Chicago Manual of Style (16^th Edition):

Cooper, Jacob. “Multi-Resolution Simulations of Delta/Diamond Wing Aerodynamics.” 2014. Doctoral Dissertation, Texas A&M University. Accessed January 17, 2021. http://hdl.handle.net/1969.1/153426.

MLA Handbook (7^th Edition):

Cooper, Jacob. “Multi-Resolution Simulations of Delta/Diamond Wing Aerodynamics.” 2014. Web. 17 Jan 2021.

Vancouver:

Cooper J. Multi-Resolution Simulations of Delta/Diamond Wing Aerodynamics. [Internet] [Doctoral dissertation]. Texas A&M University; 2014. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/1969.1/153426.

Council of Science Editors:

Cooper J. Multi-Resolution Simulations of Delta/Diamond Wing Aerodynamics. [Doctoral Dissertation]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153426

NSYSU

19. Pan, Chih-Hong. A Preliminary Study of Left Wing in Taiwan - from the Perspective of Historical Institutionalism.

Degree: Master, Political Science, 2018, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0702118-104150

► With the theme of " why did Taiwan not yet have a strong left-wing party?", this paper analyzes the factors behind it and also analyzes… (more)

▼ With the theme of " why did Taiwan not yet have a strong left-wing party?", this paper analyzes the factors behind it and also analyzes the left wing party history of Taiwan through its four periods. The first period, the period of Taisho democracy. The enlightenment and development of Taiwan's left wing (1920-1931). The left wing had been initiated in this period, but eventually turned into underground activity because of mass arrest of left wing activist by Japanese police, highlighting the asymmetric relationship between the colonizer and the colonized; the second period, the martial law period in Kuomintang Government-ruled Taiwan (1945-1987). At this stage, the Taiwanese left-wing experienced destruction and blankness. The Kuomintang Government implemented the martial law. The left wing of Taiwan was completely eliminated, and the ideological inheritance and actions of the left wing were lost, it resulting in the "left-wing fault " and the rise of ânational consciousness" in Taiwan. It highlights the state's institutional dependence on legal violent rule; in the third period, overseas Baodiao movement promoted the opportunity for Taiwan's left-wing resurgence (1970); in the fourth period, why, not yet, Taiwan has a strong left-wing party? (1987-2016). From the interaction between Taiwanese leftist and the national system of the first three periods mentioned above, plus the economic structure of Taiwan in the fourth period and the current state of the social class, we can summarize into four aspects why Taiwan has not yet a strong leftist party, (1) institutional path dependence and power inequalities. Two repressions in history caused the "Taiwan Left Wing Fault"ãlost of left-wing philosophy and action tradition; (2) The system affected actors' preferences. Causing democracy and national consciousness to prioritize class consciousness; (3) Economic development has priority. Focus on economic growth and ignore social distribution; (4) Stable social class. Taiwanâs income distribution creates stable middle class. While analyzing the above factors, this paper attempts to find out the conditions for the emergence of strong leftist parties in Taiwan. These conditions are just preliminary discussion. I hope that some materials from discussion will provide a little help to left-wing personnel in Taiwan who still seek for a development model. Advisors/Committee Members: Lin, Wen-Pin (chair), Liao, Da-Chi (committee member), Dzeng, Yi-Ren (chair).

Subjects/Keywords: class consciousness; left-wing; left-wing party

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

APA (6^th Edition):

Pan, C. (2018). A Preliminary Study of Left Wing in Taiwan - from the Perspective of Historical Institutionalism. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0702118-104150

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Pan, Chih-Hong. “A Preliminary Study of Left Wing in Taiwan - from the Perspective of Historical Institutionalism.” 2018. Thesis, NSYSU. Accessed January 17, 2021. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0702118-104150.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Pan, Chih-Hong. “A Preliminary Study of Left Wing in Taiwan - from the Perspective of Historical Institutionalism.” 2018. Web. 17 Jan 2021.

Vancouver:

Pan C. A Preliminary Study of Left Wing in Taiwan - from the Perspective of Historical Institutionalism. [Internet] [Thesis]. NSYSU; 2018. [cited 2021 Jan 17]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0702118-104150.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pan C. A Preliminary Study of Left Wing in Taiwan - from the Perspective of Historical Institutionalism. [Thesis]. NSYSU; 2018. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0702118-104150

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Manchester

20. Abdul Hamid, Mohd Faisal. Aerodynamic models for insect flight.

Degree: PhD, 2016, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/aerodynamic-models-for-insect-flight(057be27b-265a-45a0-b8d0-dc3c02a62a77).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728093

► Numerical models of insect flapping flight have previously been developed and used to simulate the performance of insect flight. These models were commonly developed via… (more)

▼ Numerical models of insect flapping flight have previously been developed and used to simulate the performance of insect flight. These models were commonly developed via Blade Element Theory, offering efficient computation, thus allowing them to be coupled with optimisation procedures for predicting optimal flight. However, the models have only been used for simulating hover flight, and often neglect the presence of the induced flow effect. Although some models account for the induced flow effect, the rapid changes of this effect on each local wing element have not been modelled. Crucially, this effect appears in both axial and radial directions, which influences the direction and magnitude of the incoming air, and hence the resulting aerodynamic forces. This thesis describes the development of flapping wing models aimed at advancing theoretical tools for simulating the optimum performance of insect flight. Two models are presented: single and tandem wing configurations for hawk moth and dragonfly, respectively. These models are designed by integrating a numerical design procedure to account for the induced flow effects. This approach facilitates the determination of the instantaneous relative velocity at any given spanwise location on the wing, following the changes of the axial and radial induced flow effects on the wing. For the dragonfly, both wings are coupled to account for the interaction of the flow, particularly the fact that the hindwing operates in the slipstream of the forewing. A heuristic optimisation procedure (particle swarming) is used to optimise the stroke or the wing kinematics at all flight conditions (hover, level, and accelerating flight). The cost function is the propulsive efficiency coupled with constraints for flight stability. The vector of the kinematic variables consists of up to 28 independent parameters (14 per wing for a dragonfly), each with a constrained range derived from the maximum available power, the flight muscle ratio, and the kinematics of real insects; this will prevent physically-unrealistic solutions of the wing motion. The model developed in this thesis accounts for the induced flow, and eliminates the dependency on the empirical translation lift coefficient. Validations are shown with numerical simulations for the hover case, and with experimental results for the forward flight case. From the results obtained, the effect of the induced velocity is found to be greatest in the middle of the stroke. The use of an optimisation process is shown to greatly improve the flapping kinematics, resulting in low power consumption in all flight conditions. In addition, a study on dragonfly flight has shown that the maximum acceleration is dependent on the size of the flight muscle.

Subjects/Keywords: 629.13; flapping wing; insect flight; tandem wing

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

APA (6^th Edition):

Abdul Hamid, M. F. (2016). Aerodynamic models for insect flight. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/aerodynamic-models-for-insect-flight(057be27b-265a-45a0-b8d0-dc3c02a62a77).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728093

Chicago Manual of Style (16^th Edition):

Abdul Hamid, Mohd Faisal. “Aerodynamic models for insect flight.” 2016. Doctoral Dissertation, University of Manchester. Accessed January 17, 2021. https://www.research.manchester.ac.uk/portal/en/theses/aerodynamic-models-for-insect-flight(057be27b-265a-45a0-b8d0-dc3c02a62a77).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728093.

MLA Handbook (7^th Edition):

Abdul Hamid, Mohd Faisal. “Aerodynamic models for insect flight.” 2016. Web. 17 Jan 2021.

Vancouver:

Abdul Hamid MF. Aerodynamic models for insect flight. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2021 Jan 17]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/aerodynamic-models-for-insect-flight(057be27b-265a-45a0-b8d0-dc3c02a62a77).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728093.

Council of Science Editors:

Abdul Hamid MF. Aerodynamic models for insect flight. [Doctoral Dissertation]. University of Manchester; 2016. Available from: https://www.research.manchester.ac.uk/portal/en/theses/aerodynamic-models-for-insect-flight(057be27b-265a-45a0-b8d0-dc3c02a62a77).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728093

University of Manchester

21. Abdul Hamid, Mohd Faisal Bin. Aerodynamic models for insect flight.

Degree: 2016, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303191

► Numerical models of insect flapping flight have previously been developed and used to simulate the performance of insect flight. These models were commonly developed via… (more)

▼ Numerical models of insect flapping flight have previously been developed and used to simulate the performance of insect flight. These models were commonly developed via Blade Element Theory, offering efficient computation, thus allowing them to be coupled with optimisation procedures for predicting optimal flight. However, the models have only been used for simulating hover flight, and often neglect the presence of the induced flow effect. Although some models account for the induced flow effect, the rapid changes of this effect on each local wing element have not been modelled. Crucially, this effect appears in both axial and radial directions, which influences the direction and magnitude of the incoming air, and hence the resulting aerodynamic forces.This thesis describes the development of flapping wing models aimed at advancing theoretical tools for simulating the optimum performance of insect flight. Two models are presented: single and tandem wing configurations for hawk moth and dragonfly, respectively. These models are designed by integrating a numerical design procedure to account for the induced flow effects. This approach facilitates the determination of the instantaneous relative velocity at any given spanwise location on the wing, following the changes of the axial and radial induced flow effects on the wing. For the dragonfly, both wings are coupled to account for the interaction of the flow, particularly the fact that the hindwing operates in the slipstream of the forewing.A heuristic optimisation procedure (particle swarming) is used to optimise the stroke or the wing kinematics at all flight conditions (hover, level, and accelerating flight). The cost function is the propulsive efficiency coupled with constraints for flight stability. The vector of the kinematic variables consists of up to 28 independent parameters (14 per wing for a dragonfly), each with a constrained range derived from the maximum available power, the flight muscle ratio, and the kinematics of real insects; this will prevent physically-unrealistic solutions of the wing motion. The model developed in this thesis accounts for the induced flow, and eliminates the dependency on the empirical translation lift coefficient. Validations are shown with numerical simulations for the hover case, and with experimental results for the forward flight case. From the results obtained, the effect of the induced velocity is found to be greatest in the middle of the stroke. The use of an optimisation process is shown to greatly improve the flapping kinematics, resulting in low power consumption in all flight conditions. In addition, a study on dragonfly flight has shown that the maximum acceleration is dependent on the size of the flight muscle. Advisors/Committee Members: IACOVIDES, HECTOR H, Iacovides, Hector, Filippone, Antonino.

Subjects/Keywords: flapping wing; insect flight; tandem wing

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

APA (6^th Edition):

Abdul Hamid, M. F. B. (2016). Aerodynamic models for insect flight. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303191

Chicago Manual of Style (16^th Edition):

Abdul Hamid, Mohd Faisal Bin. “Aerodynamic models for insect flight.” 2016. Doctoral Dissertation, University of Manchester. Accessed January 17, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303191.

MLA Handbook (7^th Edition):

Abdul Hamid, Mohd Faisal Bin. “Aerodynamic models for insect flight.” 2016. Web. 17 Jan 2021.

Vancouver:

Abdul Hamid MFB. Aerodynamic models for insect flight. [Internet] [Doctoral dissertation]. University of Manchester; 2016. [cited 2021 Jan 17]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303191.

Council of Science Editors:

Abdul Hamid MFB. Aerodynamic models for insect flight. [Doctoral Dissertation]. University of Manchester; 2016. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:303191

University of Kansas

22. Brown, Matthew Alan. A Computational Method for Determining Distributed Aerodynamic Loads on Planforms of Arbitrary Shape in Compressible Subsonic Flow.

Degree: MS, Aerospace Engineering, 2013, University of Kansas

URL: http://hdl.handle.net/1808/14195

► The methods presented in this work are intended to provided an easy to understand and easy to apply method for determining the distributed aerodynamic loads… (more)

Subjects/Keywords: Aerospace engineering; Aerodyanmic loads; Cranked wing; Wing aerodyanmics; Wing loads

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

APA (6^th Edition):

Brown, M. A. (2013). A Computational Method for Determining Distributed Aerodynamic Loads on Planforms of Arbitrary Shape in Compressible Subsonic Flow. (Masters Thesis). University of Kansas. Retrieved from http://hdl.handle.net/1808/14195

Chicago Manual of Style (16^th Edition):

Brown, Matthew Alan. “A Computational Method for Determining Distributed Aerodynamic Loads on Planforms of Arbitrary Shape in Compressible Subsonic Flow.” 2013. Masters Thesis, University of Kansas. Accessed January 17, 2021. http://hdl.handle.net/1808/14195.

MLA Handbook (7^th Edition):

Brown, Matthew Alan. “A Computational Method for Determining Distributed Aerodynamic Loads on Planforms of Arbitrary Shape in Compressible Subsonic Flow.” 2013. Web. 17 Jan 2021.

Vancouver:

Brown MA. A Computational Method for Determining Distributed Aerodynamic Loads on Planforms of Arbitrary Shape in Compressible Subsonic Flow. [Internet] [Masters thesis]. University of Kansas; 2013. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/1808/14195.

Council of Science Editors:

Brown MA. A Computational Method for Determining Distributed Aerodynamic Loads on Planforms of Arbitrary Shape in Compressible Subsonic Flow. [Masters Thesis]. University of Kansas; 2013. Available from: http://hdl.handle.net/1808/14195

Linköping University

23. Sohaib, Muhammad. Parameterized Automated Generic Model for Aircraft Wing Structural Design and Mesh Generation for Finite Element Analysis.

Degree: Machine Design, 2011, Linköping University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71264

► This master thesis work presents the development of a parameterized automated generic model for the structural design of an aircraft wing. Furthermore, in order… (more)

Subjects/Keywords: aircraft design; aircraft wing; wing spars; wing ribs; FEM; structural mesh; generic wing model; parametric wing model; automation; design; TECHNOLOGY; TEKNIKVETENSKAP

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

APA (6^th Edition):

Sohaib, M. (2011). Parameterized Automated Generic Model for Aircraft Wing Structural Design and Mesh Generation for Finite Element Analysis. (Thesis). Linköping University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71264

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Sohaib, Muhammad. “Parameterized Automated Generic Model for Aircraft Wing Structural Design and Mesh Generation for Finite Element Analysis.” 2011. Thesis, Linköping University. Accessed January 17, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71264.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Sohaib, Muhammad. “Parameterized Automated Generic Model for Aircraft Wing Structural Design and Mesh Generation for Finite Element Analysis.” 2011. Web. 17 Jan 2021.

Vancouver:

Sohaib M. Parameterized Automated Generic Model for Aircraft Wing Structural Design and Mesh Generation for Finite Element Analysis. [Internet] [Thesis]. Linköping University; 2011. [cited 2021 Jan 17]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71264.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Sohaib M. Parameterized Automated Generic Model for Aircraft Wing Structural Design and Mesh Generation for Finite Element Analysis. [Thesis]. Linköping University; 2011. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71264

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New South Wales

24. McKinnon, Douglas John. Novel efficiency evaluation methods and analysis for three-phase induction machines.

Degree: Electrical Engineering and Telecommunications, 2005, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/21869 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:704/SOURCE01?view=true

► This thesis describes new methods of evaluating the efficiency of three-phase induction machines using synthetic loading. Synthetic loading causes the induction machine to draw full-load… (more)

▼ This thesis describes new methods of evaluating the efficiency of three-phase induction machines using synthetic loading. Synthetic loading causes the induction machine to draw full-load current without the need to connect a mechanical load to the machine's drive shaft. The synthetic loading methods cause the machine to periodically accelerate and decelerate, producing an alternating motor-generator action. This action causes the machine, on average over each synthetic loading cycle, to operate at rated rms current, rated rms voltage and full-load speed, thereby producing rated copper losses, iron loss and friction and windage loss. The excitation voltages are supplied from a PWM inverter with a large capacity DC bus capable of supplying rated rms voltage.The synthetic loading methods of efficiency evaluation are verified in terms of the individual losses in the machine by using a new dynamic model that accounts for iron loss and all parameter variations. The losses are compared with the steady-state loss distribution determined using very accurate induction machine parameters. The parameters were identified using a run-up-to-speed test at rated voltage and the locked rotor and synchronous speed tests conducted with a variable voltage supply. The latter tests were used to synthesise the variations in stator leakage reactance, magnetising reactance and the equivalent iron loss resistance over the induction machine's speed range. The run-up-to-speed test was used to determine the rotor resistance and leakage reactance variations over the same speed range. The test method results showed for the first time that the rotor leakage reactance varied in the same manner as the stator leakage and magnetising reactances with respect to current. When all parameter variations are taken into account there is good agreement between theoretical and measured results for the synthetic loading methods. The synthetic loading methods are applied to three-phase induction machines with both single- and double-cage rotors to assess the effect of rotor parameter variations in the method. Various excitation waveforms for each method were used and the measured and modelled efficiencies compared to conventional efficiency test results. The results verify that it is possible to accurately evaluate the efficiency of three-phase induction machines using synthetic loading.

Subjects/Keywords: synthetic loading; induction motor; parameter identification; parameter; efficiency testing; efficiency; dual frequency; sweep frequency; constant speed of rotating magnetic field; three phase induction motor; three phase induction machine; variable rotor parameter; electric machinery; induction

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

APA (6^th Edition):

McKinnon, D. J. (2005). Novel efficiency evaluation methods and analysis for three-phase induction machines. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/21869 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:704/SOURCE01?view=true

Chicago Manual of Style (16^th Edition):

McKinnon, Douglas John. “Novel efficiency evaluation methods and analysis for three-phase induction machines.” 2005. Doctoral Dissertation, University of New South Wales. Accessed January 17, 2021. http://handle.unsw.edu.au/1959.4/21869 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:704/SOURCE01?view=true.

MLA Handbook (7^th Edition):

McKinnon, Douglas John. “Novel efficiency evaluation methods and analysis for three-phase induction machines.” 2005. Web. 17 Jan 2021.

Vancouver:

McKinnon DJ. Novel efficiency evaluation methods and analysis for three-phase induction machines. [Internet] [Doctoral dissertation]. University of New South Wales; 2005. [cited 2021 Jan 17]. Available from: http://handle.unsw.edu.au/1959.4/21869 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:704/SOURCE01?view=true.

Council of Science Editors:

McKinnon DJ. Novel efficiency evaluation methods and analysis for three-phase induction machines. [Doctoral Dissertation]. University of New South Wales; 2005. Available from: http://handle.unsw.edu.au/1959.4/21869 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:704/SOURCE01?view=true

25. Bidoggia, Benoit. Fuel cell and power converter systems : model and design : Systèmes pile à combustible et convertisseur de puissance : modélisation et conception.

Degree: Docteur es, Electronique de puissance, 2009, Tours; Università degli studi (Padoue, Italie)

URL: http://www.theses.fr/2009TOUR4027

►

Les piles à combustible sont des dispositifs qui permettent de transformer directement l’énergie chimique potentielle d’un carburant en énergie électrique. Elle sont presque toujours couplées… (more)

▼

Les piles à combustible sont des dispositifs qui permettent de transformer directement l’énergie chimique potentielle d’un carburant en énergie électrique. Elle sont presque toujours couplées à un convertisseur de puissance et l’ensemble est ici appellé « système à pile à combustible ». Le comportement de ces systèmes, les interactions entre ses composants, ainsi que leurs réponses aux stimulations extérieures ont été analysés, étudiés et mesurés. A cet effet, un système à pile à combustible complet a été modélisé. Des critères de dimensionnement pour cas où ni la pile à combustible ni le convertisseur de puissance sont à priori connus ont été identifiés et un prototype a été dimensionné et réalisé. D’autres aspects corrélatifs intéressants ont également été développés et étudiés, comme le fonctionnement du convertisseur à la limite entre les modes de conduction continu et discontinu, ainsi que son contrôle à fréquence de commutation variable. Des résultats expérimentaux et de simulation pour le système et pour les différentes parties dont il est composé sont présentés.

Fuel cells are devices in which a fuel’s chemical potential energy is directly converted into electrical energy. They are almost always coupled to a power converter and the ensemble is here called “fuel cell system.” The behaviour of such systems, the interactions between their components,and their responses to external stimulations have been analysed, studied and measured. For this purpose, a complete fuel cell system has been modelled. Sizing criteria for cases where neither the fuel cell nor the power converter are a priori known have been identified, and a prototype has been sized and built. Other interesting correlative aspects have also been developed and studied, like the operation of the power converter on the border between the discontinuousand continuous conduction modes, and its control with a variable switching frequency. Experimental and simulation results for the system and for the different parts that compose it are presented.

Le celle a combustibile sono dei dispositivi in cui l’energia chimica potenziale di un combustibile è direttamente convertita in energia elettrica. Quasi sempre le celle a combustibile sono accoppiate a un convertitore di potenza e l’insieme è qui chiamato «sistema a celle a combustibile». Il comportamento di questi sistemi, le interazioni tra i diversi componenti, nonché le loro risposte a stimoli esterni sono stati analizzati, studiati e misurati.A tal fine, un sistema completo a celle a combustibile è stato modellizzato. Sono stati identificati dei criteri di dimensionamento per casi in cui né la cella a combustibile, né il convertitore sono noti a priori, e un prototipo è stato dimensionato e realizzato. Altri interessantiaspetti correlatisonostati sviluppatie studiati,comeil funzionamento del convertitore di potenza al limite fra modo di conduzione discontinuo e continuo, e il suo controllo a frequenza di commutazione variabile. Risultati sperimentali e di simulazione per il sistema e le diverse parti…

Advisors/Committee Members: Ventura, Laurent (thesis director), Buso, Simone (thesis director).

Subjects/Keywords: Fréquence variable

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

APA (6^th Edition):

Bidoggia, B. (2009). Fuel cell and power converter systems : model and design : Systèmes pile à combustible et convertisseur de puissance : modélisation et conception. (Doctoral Dissertation). Tours; Università degli studi (Padoue, Italie). Retrieved from http://www.theses.fr/2009TOUR4027

Chicago Manual of Style (16^th Edition):

Bidoggia, Benoit. “Fuel cell and power converter systems : model and design : Systèmes pile à combustible et convertisseur de puissance : modélisation et conception.” 2009. Doctoral Dissertation, Tours; Università degli studi (Padoue, Italie). Accessed January 17, 2021. http://www.theses.fr/2009TOUR4027.

MLA Handbook (7^th Edition):

Bidoggia, Benoit. “Fuel cell and power converter systems : model and design : Systèmes pile à combustible et convertisseur de puissance : modélisation et conception.” 2009. Web. 17 Jan 2021.

Vancouver:

Bidoggia B. Fuel cell and power converter systems : model and design : Systèmes pile à combustible et convertisseur de puissance : modélisation et conception. [Internet] [Doctoral dissertation]. Tours; Università degli studi (Padoue, Italie); 2009. [cited 2021 Jan 17]. Available from: http://www.theses.fr/2009TOUR4027.

Council of Science Editors:

Bidoggia B. Fuel cell and power converter systems : model and design : Systèmes pile à combustible et convertisseur de puissance : modélisation et conception. [Doctoral Dissertation]. Tours; Università degli studi (Padoue, Italie); 2009. Available from: http://www.theses.fr/2009TOUR4027

University of California – San Diego

26. Roberts, Benjamin Zalman. Towards the Development of a Rat Model of Human Targeted Cognitive Training.

Degree: Biology, 2018, University of California – San Diego

URL: http://www.escholarship.org/uc/item/12v8418r

► Cognitive deficits are characteristic symptoms of schizophrenia, but remain largely untreated. Targeted Cognitive Training (TCT), a computerized training regimen designed to enhance spared function, is… (more)

Subjects/Keywords: Biology; Behavioral sciences; Neurosciences; Auditory Sweep Discrimination Task; Rat Sweep Discrimination Task; Schizophrenia; Targeted Cognitive Training

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APA (6^th Edition):

Roberts, B. Z. (2018). Towards the Development of a Rat Model of Human Targeted Cognitive Training. (Thesis). University of California – San Diego. Retrieved from http://www.escholarship.org/uc/item/12v8418r

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Roberts, Benjamin Zalman. “Towards the Development of a Rat Model of Human Targeted Cognitive Training.” 2018. Thesis, University of California – San Diego. Accessed January 17, 2021. http://www.escholarship.org/uc/item/12v8418r.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Roberts, Benjamin Zalman. “Towards the Development of a Rat Model of Human Targeted Cognitive Training.” 2018. Web. 17 Jan 2021.

Vancouver:

Roberts BZ. Towards the Development of a Rat Model of Human Targeted Cognitive Training. [Internet] [Thesis]. University of California – San Diego; 2018. [cited 2021 Jan 17]. Available from: http://www.escholarship.org/uc/item/12v8418r.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Roberts BZ. Towards the Development of a Rat Model of Human Targeted Cognitive Training. [Thesis]. University of California – San Diego; 2018. Available from: http://www.escholarship.org/uc/item/12v8418r

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Brno University of Technology

27. Paliesek, Jakub. Změření vlivu akustiky prostředí na úspěšnost rozpoznávače řeči: Measurment of Impact of Environment Acoustics on Speech Recognition Accuracy.

Degree: 2019, Brno University of Technology

URL: http://hdl.handle.net/11012/85195

► This bachelor thesis deals with investigation of impacts of acoustical parameters on automatic speech recognition (ASR) accuracy. Used ASRs were evaluated on Speecon, Temic and… (more)

Subjects/Keywords: rozpoznávanie reči; akustika; impulzná odozva; exponential sine sweep; speech recognition; acoustics; impulse response; exponential sine sweep

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APA (6^th Edition):

Paliesek, J. (2019). Změření vlivu akustiky prostředí na úspěšnost rozpoznávače řeči: Measurment of Impact of Environment Acoustics on Speech Recognition Accuracy. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/85195

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Paliesek, Jakub. “Změření vlivu akustiky prostředí na úspěšnost rozpoznávače řeči: Measurment of Impact of Environment Acoustics on Speech Recognition Accuracy.” 2019. Thesis, Brno University of Technology. Accessed January 17, 2021. http://hdl.handle.net/11012/85195.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Paliesek, Jakub. “Změření vlivu akustiky prostředí na úspěšnost rozpoznávače řeči: Measurment of Impact of Environment Acoustics on Speech Recognition Accuracy.” 2019. Web. 17 Jan 2021.

Vancouver:

Paliesek J. Změření vlivu akustiky prostředí na úspěšnost rozpoznávače řeči: Measurment of Impact of Environment Acoustics on Speech Recognition Accuracy. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/11012/85195.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Paliesek J. Změření vlivu akustiky prostředí na úspěšnost rozpoznávače řeči: Measurment of Impact of Environment Acoustics on Speech Recognition Accuracy. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/85195

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Carnegie Mellon University

28. Colmenares, David. Design and Control of a Resonant, Flapping Wing Micro Aerial Vehicle Capable of Controlled Flight.

Degree: 2017, Carnegie Mellon University

URL: http://repository.cmu.edu/dissertations/1032

► Small scale unmanned aircraft, such as quadrotors, that are quickly emerging as versatile tools for a wide range of applications including search and rescue, hazardous… (more)

▼ Small scale unmanned aircraft, such as quadrotors, that are quickly emerging as versatile tools for a wide range of applications including search and rescue, hazardous environment exploration, or just shooting great video, are known as micro air vehicles (MAVs). However, for millimeter scale vehicles with weights under 10 grams, conventional flight technologies become greatly inefficient and instead inspiration is drawn from biology. Flapping wing MAVs (FWMAVs) have been created based on insects and hummingbirds in an effort to emulate their extreme agility and ability to hover in place. FWMAVs possess unique capabilities in terms of maneuverability, small size, and ability to operate in dynamic environments that make them particularly well suited for environmental monitoring and swarm applications such as artificial crop pollination. Despite their advantages, significant challenges in fabrication, power, and control must be overcome in order to make FWMAVs a reliable platform. Current designs suffer from high mechanical complexity and often rely on off-board power, sensing, and control, which compromises their autonomy and limits practical applications. The goal of my research is to develop a simple FWMAV design that provides high efficiency and controllability. An efficient, simple, and controllable vehicle design is developed utilizing the principles of resonance, emulation of biological flight control, and under-actuation. A highly efficient, resonant actuator is achieved by attaching a spring in parallel to the output shaft of a commercial geared DC micro-motor. This actuator directly drives the wings of the vehicle, allowing them to be controlled precisely and independently. This direct control strategy emulates biology and differs from other FWMAV designs that utilize complicated transmissions to generate flapping from rotary motor output. Direct control of the wings allows for emulation of biological wing kinematics, resulting in control based on wing motion alone. Furthermore, under-actuation is employed to mimic the rotational motion of insect wings. A rotational joint is added between the motor and wing membrane such that the wing rotates passively in response to aerodynamic forces that are generated as the wing is driven. This design is realized in several stages, initial prototyping, simulation and development of the actuator and wings, then finally a control system is developed. First the system was modeled and improved experimentally in order to achieve lift off. Improvements to the actuator were realized through component variation and custom fabrication increasing torque and power density by 161.1% and 666.8% respectively compared to the gearmotor alone and increased the resonant operating frequency of the vehicle from 4 Hz to 23 Hz. Advances in wing fabrication allowed for flexible wings that increased translational lift production by 35.3%, aerodynamic efficiency by 41.3%, and the effective lift coefficient by 63.7% with dynamic twisting. A robust control architecture was then developed iteratively…

Subjects/Keywords: Micro Aerial Vehicle; Flapping wing; Resonant Actuator; DC motor; Thermal Model; Flexible Wing; Wing Twist

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

APA (6^th Edition):

Colmenares, D. (2017). Design and Control of a Resonant, Flapping Wing Micro Aerial Vehicle Capable of Controlled Flight. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1032

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Colmenares, David. “Design and Control of a Resonant, Flapping Wing Micro Aerial Vehicle Capable of Controlled Flight.” 2017. Thesis, Carnegie Mellon University. Accessed January 17, 2021. http://repository.cmu.edu/dissertations/1032.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Colmenares, David. “Design and Control of a Resonant, Flapping Wing Micro Aerial Vehicle Capable of Controlled Flight.” 2017. Web. 17 Jan 2021.

Vancouver:

Colmenares D. Design and Control of a Resonant, Flapping Wing Micro Aerial Vehicle Capable of Controlled Flight. [Internet] [Thesis]. Carnegie Mellon University; 2017. [cited 2021 Jan 17]. Available from: http://repository.cmu.edu/dissertations/1032.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Colmenares D. Design and Control of a Resonant, Flapping Wing Micro Aerial Vehicle Capable of Controlled Flight. [Thesis]. Carnegie Mellon University; 2017. Available from: http://repository.cmu.edu/dissertations/1032

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Indian Institute of Science

29. Mukherjee, Sujoy. Structural Modeling And Analysis Of Insect Scale Flapping Wing.

Degree: PhD, Faculty of Engineering, 2013, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/2021

► Micro Air Vehicles (MAVs) are defined as a class of vehicles with their larger dimension not exceeding 15 cm and weighing 100 gm. The three… (more)

▼ Micro Air Vehicles (MAVs) are defined as a class of vehicles with their larger dimension not exceeding 15 cm and weighing 100 gm. The three main approaches for providing lift for such vehicles are through fixed, rotating and flapping wings. The flapping wing MAVs are more efficient in the low Reynolds-number regime than conventional wings and rotors. Natural flapping ﬂyers, such as birds and insects, serve as a natural source of inspiration for the development of MAV. Flapping wing design is one of the major challenges to develop an MAV because it is not only responsible for the lift, but also propulsion and maneuvers. Two important issues are addressed in this thesis: (1) an equivalent beam-type modeling of actual insect wing is proposed based on the experimental data and (2) development of the numerical framework for design and analysis of insect scale smart flapping wing. The experimental data is used for structural modeling of the blowfly Calliphora wing as a stepped cantilever beam with nine spanwise sections of varying mass per unit lengths, flexural rigidity (EI) and torsional rigidity (GJ) values. Natural frequencies, both in bending and torsion, are obtained by solving the homogeneous part of the respective governing differential equations using the finite element method. It is found that natural frequency in bending and torsion are 3.17 and 1.57 times higher than flapping frequency of Calliphora wing, respectively. The results provide guidelines for the biomimetic structural design of insect-scale flapping wings. In addition to the structural modeling of the insect wing, development of the biomimetic mechanisms played a very important role to achieve a deeper insight of the flapping ﬂight. Current biomimetic flapping wing mechanisms are either dynamically scaled or rely on pneumatic and motor-driven flapping actuators. Unfortunately, these mechanisms become bulky and flap at very low frequency. Moreover, mechanisms designed with conventional actuators lead to high weight and system-complexity which makes it difficult to mimic the complex wingbeat kinematics of the natural flyers. The usage of the actuator made of smart materials such as ionic polymer metal composites (IPMCs) and piezoceramics to design flapping wings is a potential alternative. IPMCs are a relatively new type of smart material that belongs to the family of Electroactive Polymers (EAP) which is also known as “artificial muscles”. In this work, structural modeling and aerodynamic analysis of a dragonﬂy inspired IPMC flapping wing are performed using numerical simulations. An optimization study is performed to obtain improved flapping actuation of the IPMC wing. Later, a comparative study of the performances of three IPMC flapping wings having the same size as the actual wings of three different dragonﬂy species Aeshna Multicolor, Anax Parthenope Julius and Sympetrum Frequens is conducted. It is found that the IPMC wing generates sufficient lift to support its own weight and carry a small payload. In addition to the IPMC, piezoelectric… Advisors/Committee Members: Ganguli, Ranjan (advisor).

Subjects/Keywords: Flapping Wing; Micro Air Vehicles (MAVs); Calliphora Wing; Flapping Wings; Twisting Wing; Flapping Flight; Aeronautics

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

APA (6^th Edition):

Mukherjee, S. (2013). Structural Modeling And Analysis Of Insect Scale Flapping Wing. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2021

Chicago Manual of Style (16^th Edition):

Mukherjee, Sujoy. “Structural Modeling And Analysis Of Insect Scale Flapping Wing.” 2013. Doctoral Dissertation, Indian Institute of Science. Accessed January 17, 2021. http://etd.iisc.ac.in/handle/2005/2021.

MLA Handbook (7^th Edition):

Mukherjee, Sujoy. “Structural Modeling And Analysis Of Insect Scale Flapping Wing.” 2013. Web. 17 Jan 2021.

Vancouver:

Mukherjee S. Structural Modeling And Analysis Of Insect Scale Flapping Wing. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2013. [cited 2021 Jan 17]. Available from: http://etd.iisc.ac.in/handle/2005/2021.

Council of Science Editors:

Mukherjee S. Structural Modeling And Analysis Of Insect Scale Flapping Wing. [Doctoral Dissertation]. Indian Institute of Science; 2013. Available from: http://etd.iisc.ac.in/handle/2005/2021

University of Rochester

30. Loehlin, David Walker (1981 - ); Werren, John H. Genetics of size and shape evolution in Nasonia.

Degree: PhD, 2012, University of Rochester

URL: http://hdl.handle.net/1802/19345

► My research addresses a fundamental question in biology: What genes and genetic changes are responsible for size and shape differences between species? In Chapter 1,… (more)

▼ My research addresses a fundamental question in biology: What genes and genetic changes are responsible for size and shape differences between species? In Chapter 1, I review the genetics of growth and what patterns might be found in the genetic changes that underlie the evolution of size and shape differences. While much is known about growth-regulating genes and their roles in human disease, one aspect is not well understood: which parts of the growth gene network specify the sizes and shapes of organs. Naturally occurring differences in size and shape, especially species differences, can be used to answer this question. An analysis of the small number of studies of organ size evolution, including my own work, points to a prominent role for cis-regulatory changes to signaling genes. This suggests that these upstream parts of the growth gene network are where many aspects of size and shape are specified. I next focus on determining the genetic basis of huge differences in wing size between two closely related wasps, Nasonia vitripennis and N. giraulti. In Chapter 2, I (along with collaborators) identify the genetic basis of the wing-size1 (ws1) quantitative trait locus (QTL), which changes Nasonia male wing area by 45% with no effect on females. Ws1 maps to a noncoding cis-regulatory element adjacent to the doublesex (dsx) gene and causes wing-specific changes in dsx expression. The capacity for cis-regulatory elements to give a gene new sex- and tissue-specific expression may explain how a conserved sex-signaling gene became recruited to regulate organ size. Chapters 3 and 4 focus on a Nasonia wing shape QTL, widerwing (wdw). In Chapter 3 I report the identification, morphological effects and evolution of wdw in four Nasonia species. In Chapter 4 I report the genetic basis of wdw. The wdw QTL maps down to one gene: the wasp version of unpaired (upd), a Drosophila cell-proliferation regulator in the JAK/STAT signaling pathway. Multiple changes around this upd-like gene are involved, each of which causes spatiotemporal differences in upd-like expression and corresponding spatial changes in wing size, revealing that wdw is a hotspot of wing size evolution.

Subjects/Keywords: Doublesex; Morphology; Unpaired; Wing

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

APA (6^th Edition):

Loehlin, David Walker (1981 - ); Werren, J. H. (2012). Genetics of size and shape evolution in Nasonia. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/19345

Chicago Manual of Style (16^th Edition):

Loehlin, David Walker (1981 - ); Werren, John H. “Genetics of size and shape evolution in Nasonia.” 2012. Doctoral Dissertation, University of Rochester. Accessed January 17, 2021. http://hdl.handle.net/1802/19345.

MLA Handbook (7^th Edition):

Loehlin, David Walker (1981 - ); Werren, John H. “Genetics of size and shape evolution in Nasonia.” 2012. Web. 17 Jan 2021.

Vancouver:

Loehlin, David Walker (1981 - ); Werren JH. Genetics of size and shape evolution in Nasonia. [Internet] [Doctoral dissertation]. University of Rochester; 2012. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/1802/19345.

Council of Science Editors:

Loehlin, David Walker (1981 - ); Werren JH. Genetics of size and shape evolution in Nasonia. [Doctoral Dissertation]. University of Rochester; 2012. Available from: http://hdl.handle.net/1802/19345

Open Access Theses and Dissertations