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Autonomous Mobility And Manipulation Of A 9-Dof Wmra, William Garrett Pence 2011 University of South Florida

Autonomous Mobility And Manipulation Of A 9-Dof Wmra, William Garrett Pence

USF Tampa Graduate Theses and Dissertations

The wheelchair-mounted robotic arm (WMRA) is a 9-degree of freedom (DoF) assistive system that consists of a 2-DoF modified commercial power wheelchair and a custom 7-DoF robotic arm. Kinematics and control methodology for the 9-DoF system that combine mobility and manipulation have been previously developed and implemented. This combined control allows the wheelchair and robotic arm to follow a single trajectory based on weighted optimizations. However, for the execution of activities of daily living (ADL) in the real-world environment, modified control techniques have been implemented.

In order to execute macro ADL tasks, such as a "go to and pick up" …


A Detailed And Systematic Investigation Of Personal Ventilation Systems, Jackie Russo 2011 Syracuse University

A Detailed And Systematic Investigation Of Personal Ventilation Systems, Jackie Russo

Mechanical and Aerospace Engineering - Dissertations

This research investigates the use of personal ventilation (PV) in a typical office space as a means of contaminant removal from ones breathing zone (BZ). For this work, a validated computational model was developed and used for PV assessment under different scenarios. Experimental data of Khalifa et al. (2009), Ito (2007) and Rim et al. (2009) were used to validate a computational model that is capable of simulating indoor chemical reactions with excellent agreement compared with the experiments. Through the validation process, various computational parameters were determined to be significant for producing accurate results. Grid resolution, geometry, far field BCs, …


Negative Pressure Characteristics Of An Evaporating Meniscus At Nanoscale, Shalabh Maroo, J N. Chung 2011 Syracuse University

Negative Pressure Characteristics Of An Evaporating Meniscus At Nanoscale, Shalabh Maroo, J N. Chung

Mechanical and Aerospace Engineering - All Scholarship

This study aims at understanding the characteristics of negative liquid pressures at the nanoscale using molecular dynamics simulation. A nano-meniscus is formed by placing liquid argon on a platinum wall between two nanochannels filled with the same liquid. Evaporation is simulated in the meniscus by increasing the temperature of the platinum wall for two different cases. Non-evaporating films are obtained at the center of the meniscus. The liquid film in the non-evaporating and adjacent regions is found to be under high absolute negative pressures. Cavitation cannot occur in these regions as the capillary height is smaller than the critical cavitation …


Estimating Industrial Building Energy Savings Using Inverse Simulation, Franc Server, J. Kelly Kissock, Dan Brown, Steve Mulqueen 2011 University of Dayton

Estimating Industrial Building Energy Savings Using Inverse Simulation, Franc Server, J. Kelly Kissock, Dan Brown, Steve Mulqueen

Mechanical and Aerospace Engineering Faculty Publications

Estimating energy savings from retrofitting existing building systems is traditionally a time intensive process, accomplished by developing a detailed building simulation model, running the model with actual weather data, calibrating the model to actual energy use data, modifying the model to include the proposed changes, then running the base and proposed models with typical weather data to estimate typical energy savings. This paper describes a less time-intensive method of estimating energy savings in industrial buildings using actual monthly energy consumption and weather data. The method begins by developing a multivariate three-parameter changepoint regression model of facility energy use. Next, the …


Heat Transfer Study Of A Triple Row Impingement Channel At Large Impingement Heights, Roberto Claretti 2011 University of Central Florida

Heat Transfer Study Of A Triple Row Impingement Channel At Large Impingement Heights, Roberto Claretti

HIM 1990-2015

Advanced cooling techniques are required to increase the Brayton cycle temperature ratio necessary for the increase of the overall cycle's efficiency. Current turbine components are cooled with an array of internal cooling channels in the midchord section of the blade, pin fin arrays at the trailing edge and impingement channels in the leading edge. Impingement channels provide the designer with high convective coefficients on the target surface. Increasing the heat transfer coefficient of these channels has been a subject of research for the past 20 years. In the current study, a triple row impingement channel is studied with a jet …


Energy-Economical Heuristically Based Control Of Compass Gait Walking On Stochastically Varying Terrain, Christian Hubicki 2011 Bucknell University

Energy-Economical Heuristically Based Control Of Compass Gait Walking On Stochastically Varying Terrain, Christian Hubicki

Master’s Theses

Investigation uses simulation to explore the inherent tradeoffs ofcontrolling high-speed and highly robust walking robots while minimizing energy consumption. Using a novel controller which optimizes robustness, energy economy, and speed of a simulated robot on rough terrain, the user can adjust their priorities between these three outcome measures and systematically generate a performance curveassessing the tradeoffs associated with these metrics.


Report For 2011 Urco Funded Experiment: Development Of Optimal Bubble-Seeding Microheaters To Study Nucleate Boiling Heat Transfer In Microgravity, Ryan Martineau 2011 Utah State University

Report For 2011 Urco Funded Experiment: Development Of Optimal Bubble-Seeding Microheaters To Study Nucleate Boiling Heat Transfer In Microgravity, Ryan Martineau

Reports and Proposals

No abstract provided.


Toward A Zero Energy Home: Applying Swiss Building Practices/Attitudes To U.S. Residential Construction, Daphene C. Koch, William Hutzel, Jason M. Kutch, Eric A. Holt 2011 School of Engineering Technology, Purdue University, United States of America

Toward A Zero Energy Home: Applying Swiss Building Practices/Attitudes To U.S. Residential Construction, Daphene C. Koch, William Hutzel, Jason M. Kutch, Eric A. Holt

School of Engineering Technology Faculty Publications

This project evaluated typical U.S. and Swiss homes to identify construction practices that are most energy efficient and have economic payback. A net zero energy home (ZEH) produces as much energy as is consumed in it over time. Students in a College o f Technology in a Midwest Indiana State University and a technical University in Switzerland resulted in developing models of homes that combined U.S. and Swiss standards. The project was completed in two phases: during the first phase o f this project, construction costs, energy use, and economic payback was calculated for six homes that were designed using …


Comparative Analysis Of A Low-Speed Wind Tunnel Designed For Renewable Energy Applications, Craig A. Zehrung 2011 Purdue University

Comparative Analysis Of A Low-Speed Wind Tunnel Designed For Renewable Energy Applications, Craig A. Zehrung

Purdue Polytechnic Masters Theses

This thesis describes the design, testing, and validation of an open-circuit, mid-sized wind tunnel used for the teaching of undergraduate courses and testing of green energy wind turbines. This thesis uses computational fluid dynamics to determine theoretical values for flow of the wind tunnel which were statistically compared to actual values of fluid flow. An overall analysis of efficiency and effectiveness were also performed. However, aerodynamic testing of actual prototype turbines will not be covered in this thesis, as it does not concern the tunnels adherence to theoretical flow values.


Impact Of Self-Rewetting Aqueous Solutions On Boiling With Advanced Heat Transfer Applications, Mostafa Morovati 2011 CUNY City College

Impact Of Self-Rewetting Aqueous Solutions On Boiling With Advanced Heat Transfer Applications, Mostafa Morovati

Dissertations and Theses

"Pool boiling experiments have been conducted with self-rewetting fluids consisting of aqueous butanol and pentanol solution to study the boiling heat transfer enhancement at pressures of 1 ~ 4 bars. Although self-rewetting fluids have been used to enhance the performance of heat pipes, boiling heat transfer characteristics are yet to be fully understood especially at pressures above atmospheric. Pool boiling experiments with aqueous butanol and pentanol solutions were performed using an electrically heated platinum wire to obtain pool boiling heat transfer data up to the Critical Heat Flux (CHF). Aqueous solutions with butanol concentrations 2-7% showed enhanced heat transfer coefficients …


Low-Cost Prosthetic Leg For The Vida Nueva Prosthesis Clinic, Sarah M. Baker, Justin G. Lekos, Jen Van Donk, Kevin Yamauchi 2011 California Polytechnic State University - San Luis Obispo

Low-Cost Prosthetic Leg For The Vida Nueva Prosthesis Clinic, Sarah M. Baker, Justin G. Lekos, Jen Van Donk, Kevin Yamauchi

Mechanical Engineering

The Piernas de Vida team partnered with the Vida Nueva Clinic of Prostheses and Orthoses in Choluteca, Honduras to design, plan, and implement a prosthetic foot that could be manufactured entirely by the technicians at the clinic in order to reduce their costs and ultimately allow them to serve more patients each year. Currently, the clinic uses a prefabricated prosthetic lower limb provided by the International Committee of the Red Cross (ICRC) which can be adapted to both transDfemoral and transDtibial patients. The team has successfully developed a foot, currently called the Layer Foot, which can be used by the …


A Method For Defining Wind Turbine Setback Standards, Jonathan Rogers, Nathan Slegers, Mark Costello 2011 Georgia Institute of Technology - Main Campus

A Method For Defining Wind Turbine Setback Standards, Jonathan Rogers, Nathan Slegers, Mark Costello

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Setback distances established by regulatory authorities to minimize the probability of blade fragment impact with roads, structures and infrastructure can often have a significant impact on wind farm development. However, these minimum distance requirements typically rely on arbitrary rules of thumb and are not based on a physical or probabilistic analysis of blade throw. The work reported here uses a probabilistic approach to evaluate the effectiveness of current standards and to propose a new technique for determining setback distances. This is accomplished through the use of a dynamic model of wind turbine blade failure coupled with Monte Carlo simulation techniques …


Techniques From Workshops On Teaching: Implementing The Concepts And Evaluating Our Approaches, Michael R. Foster, Justin R. Vander Werff 2011 George Fox University

Techniques From Workshops On Teaching: Implementing The Concepts And Evaluating Our Approaches, Michael R. Foster, Justin R. Vander Werff

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

The challenges for new engineering educators abound and there are never enough hours in a day or days in a week. Young educators may lack confidence in course subject material given that they have never taught (the topic and/or in a classroom) before. In addition, their knowledge of teaching pedagogy and classroom management strategies often lacks refinement since their education is almost exclusively in a field of engineering rather than education. Teaching workshops have been developed to expose instructors in higher education to practical teaching pedagogy and effective classroom management. These workshops often emphasize research-based methods including use of clearly …


Development Of A Humanoid Robot Arm For Use In Urban Environments, Brenton Noll 2011 Bucknell University

Development Of A Humanoid Robot Arm For Use In Urban Environments, Brenton Noll

Master’s Theses

The Bucknell Humanoid Robot Arm project was developed in order toprovide a lightweight robotic arm for the IHMC / Bucknell University bipedal robot that will provide a means of manipulation and facilitate operations in urban environments. The resulting fabricated arm described in this thesis weighs only 13 pounds, and is capable of holding 11 pounds fully outstretched, lifting objects such as tools, and it can open doors. It is also capable of being easily integrated with the IHMC / Bucknell University biped. This thesis provides an introduction to robots themselves, discusses the goals of the Bucknell Humanoid Robot Arm project, …


Gas Turbine Blade Tip And Near Tip Heat Transfer With Film Cooling, Gregory Kramer 2011 Louisiana State University and Agricultural and Mechanical College

Gas Turbine Blade Tip And Near Tip Heat Transfer With Film Cooling, Gregory Kramer

LSU Master's Theses

Gas turbine blade tips experience very high thermal loads due to high temperature combustion gases and tip leakage flows. This leads to the tip region being very susceptible to experiencing failures. To better understand these effects, experiments were performed in a suction-type low speed wind tunnel cascade to determine heat transfer coefficients and film cooling effectiveness distributions on a highly-loaded 2-D gas turbine blade model in the tip and near-tip regions. The blade shape was generated to match the pressure coefficients of the operating turbine blade design. The model featured multiple tip and pressure side film cooling holes and a …


High Frequency Thermally Actuated Single Crystalline Silicon Micromechanical Resonators With Piezoresistive Readout, Amir Rahafrooz 2011 University of Denver

High Frequency Thermally Actuated Single Crystalline Silicon Micromechanical Resonators With Piezoresistive Readout, Amir Rahafrooz

Electronic Theses and Dissertations

Over the past decades there has been a great deal of research on developing high frequency micromechanical resonators. As the two most common and conventional MEMS resonators, piezoelectric and electrostatic resonators have been at the center of attention despite having some drawbacks. Piezoelectric resonators provide low impedances that make them compatible with other low impedance electronic components, however they have low quality factors and complicated fabrication processes. In case of electrostatic resonators, they have higher quality factors but the need for smaller transductions gaps complicates their fabrication process and causes squeezed film damping in Air. In addition, the operation of …


Label-Free Biochemical Recognition Using Mems Resonators For Microarray Technology, Babak Tousifar 2011 University of Denver

Label-Free Biochemical Recognition Using Mems Resonators For Microarray Technology, Babak Tousifar

Electronic Theses and Dissertations

Highly sensitive biosensors capable of detecting and characterizing smallest quantities of cellular and molecular targets are needed in pharmaceutical and medical diagnostics industries. In this work, the importance of biological target recognition specifically proteins through microarray technologies has been discussed and the most successful tools and techniques have been studied. Moreover, a thermally actuated Micro Electro-Mechanical Systems (MEMS) resonator has been demonstrated and fabricated in this work as an accurate, reliable and low cost biotechnology tool. As a proof of concept, amine to epoxide coupling of octadecylamine to functionalized silicon dioxide surface have been shown through resonator frequency monitoring. The …


An Integrated Platform To Increase The Range/Endurance Of Unmanned Helicopters, Roy Godzdanker 2011 University of Denver

An Integrated Platform To Increase The Range/Endurance Of Unmanned Helicopters, Roy Godzdanker

Electronic Theses and Dissertations

Class I (kg) autonomous helicopters are becoming increasingly popular for a wide range of non-military applications such as, surveillance, reconnaissance, traffic monitoring, emergency response, agricultural spraying, and many other "eye in the sky" missions. However, an efficient landing/takeoff platform with refueling/recharging capabilities has not yet been developed to increase the endurance and decrease the cost for Class I helicopters.

This dissertation presents a three-prong approach for increasing the range and endurance of Class I autonomous helicopters, which will then spur demand by non-military organizations wanting to take advantage of such capabilities and, therefore, drop their price. The proposed Intelligent Self-Leveling …


Effects Of A Heated Turbulent Boundary Layer On Surface Pressure Fluctuations, David William Rich 2011 University of Mississippi

Effects Of A Heated Turbulent Boundary Layer On Surface Pressure Fluctuations, David William Rich

Electronic Theses and Dissertations

Recent work has shown that spatial correlation of surface pressure fluctuations in a fully turbulent atmospheric boundary layer (ABL) can give information about the velocity field and turbulence. This is of particular importance to the future of wind energy to predict the incoming velocity flow field of wind turbines so as to actively control them for peak operating efficiency and damage reduction. All of the environmental effects on the surface pressure fluctuations need to be fully understood before a suitable flow prediction algorithm can be constructed. One such environmental effect which has not been previously studied is the effect of …


Quantification Of An Ultrasound Test Apparatus And Its Potential Use To Control Nuisance Species In Commercial Aquaculture Settings, Bradley T. Goodwiller 2011 University of Mississippi

Quantification Of An Ultrasound Test Apparatus And Its Potential Use To Control Nuisance Species In Commercial Aquaculture Settings, Bradley T. Goodwiller

Electronic Theses and Dissertations

As one step in the investigation of using acoustics to improve aquaculture production, work was pursued on the possible use of ultrasound to control the Bolbophorus trematode in commercial catfish ponds. The trematode population can be controlled by eliminating the host ram's horn snail via exposure to high amplitude ultrasound. Initial laboratory tests indicated that a commercially available sonicator (operating at 20 kHz) is capable of killing individual snails in fish tanks. More thorough testing indicated efficiency rates of approximately 35% on batches of 10 snails. In addition to the snails killed immediately, there was evidence that the sonication technique …


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