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Title: A COMPARISON OF META-ANALYTIC PROCEDURES WHEN PRE- AND POSTTEST VARIANCES ARE HETEROGENEOUS
Creator: Collins, Michael W.
Date: 2011-11, 2011-12
Description: Meta-analysis is a statistical method for aggregating summary results from archival research. Traditional meta-analysis procedures that...
Show moreMeta-analysis is a statistical method for aggregating summary results from archival research. Traditional meta-analysis procedures that involve repeated measures assume homogeneous variances in pretests and posttests, an assumption which is often violated in training evaluation contexts due to variance inflation in posttests. A new meta-analytic procedure that allows for heterogeneous variance in pretests and posttests was tested in the context of leadership and managerial training programs. Application of the new method revealed greater sampling variance and less between-study variance than traditional meta-analysis with little effect on estimation of the mean effect size. However, the procedure screened out a large number of studies due to the intensive data requirements, which limited the number of usable studies for the meta-analysis.
Ph.D. in Psychology, December 2011
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Title: FROM FIREPLACE TO STEAM: DOMESTIC HEATING TECHNOLOGY IN NORTHEASTERN UNITED STATES, 1840-1890
Creator: Morais, Caroline
Date: 2012-12-07, 2012-12
Description: Why study nineteenth-century domestic heating technology? Besides its pop- ular appeal and utilitarian value, domestic heating technology is...
Show moreWhy study nineteenth-century domestic heating technology? Besides its pop- ular appeal and utilitarian value, domestic heating technology is one of the most signi cant yet least explored subjects in American history. American processes of industrialization, manufacturing, and transportation are well known, however, the impact of technological changes on the home is less familiar. Understanding past everyday lives is crucial to recognize the processes of adjusting to new technologies, particularly those technologies essential to today's American lives that have been overlooked. This dissertation examines the shift in domestic heating modes in North- eastern United States between the decades of 1840 and 1890. After carefully reviewing the literature on the subject of nineteenth-century heating technology, I asked myself why the domestic setting has received little schol- arly or historical attention in comparison to those of industrial and commercial set- tings. The answer lies on the fact that, traditionally, historians have been more interested in public events than in those within the private environment. The signi - cance of domestic heating technology has also been reduced duo to divisions between scholarly elds and disciplines. Also, the interpretation of artifacts has been more the eld of anthropologists than that of historians. Thus, few studies have narrowed their focus to a speci c topic of technology and the di erences in form, function, and cultural settings of its development. Investigating a historically obsolete technology and understanding the way people used it can be challenging. Domestic heating technology has advanced, and attitudes towards it have changed over time. It has been di cult to nd physical evidence of early examples in the form in which people originally used it daily. Addi- tionally, few people took the time to record their everyday-life interactions with the equipment and actual models of the old technology are hard to nd. Mid-nineteenth iv century American household heating apparatuses are a clear example of that. The ine ciency of systems previous to central heating challenged inventors and manufac- tures to search for and invest in more convenient and economical options to improve the quality of life. With the development of household heating technology, people gradually abandoned replaces and stoves and adopted furnaces and central heating as their primary source of heating. My goal was to explore the evolving meaning of domestic heating systems as a technological symbol. By analyzing the changing responses from one technological development to the other, I was able to identify some main points that made appro- priate domestic heating and ventilation a necessity for both comfort and health of Americans who lived in the focused period. I chose the ve decades between 1840 and 1890 because most of the modern conveniences were introduced into American homes for the rst time during those years and for their signi cance to the country's technological history. The Northeastern region was chosen as the geographical focus because the dispersion of knowledge began there, especially knowledge in heating and ventila- tion technology and apparatus manufacturing. The sources for the study included domestic advice manuals, architectural pattern books, engineering and architectural periodicals, patent records, manufacturers' and dealers' sales catalogs, and census schedules. The technological development of heating and ventilation systems culmi- nated with the advent of central heating, which currently represents the technology of domestic heating methods. In the design of American homes, central heating systems have superseded previous apparatuses such as replaces and stoves. They have become an option rather than a necessity of a comfortable and convenient domestic life. This disserta- tion is a brief study of that moment of transition. My intention was to expand on v basic assumptions about the technological development of the American home, not to challenge them. There has already been a considerable amount of attention given to the study of the American home and home life. Therefore, I see my research as an addition to the growing knowledge of the history of American domestic technology and the people and innovations that enabled its development.
PH.D in Philosophy in Architecture, December 2012
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Title: HARDWARE-EFFICIENT VLSI IMPLEMENTATION FOR PARALLEL LINEAR-PHASE DIGITAL FIR FILTER
Creator: Tsao, Yu-chi
Date: 2011-11, 2011-12
Description: Along with the explosive growth of multimedia applications, the number of gates required and the area consumed in very-large-scale integration...
Show moreAlong with the explosive growth of multimedia applications, the number of gates required and the area consumed in very-large-scale integration (VLSI) for digital signal processing (DSP) is getting higher and higher. Therefore, the demand for low-complexity and low-cost VLSI architectures for DSP, which occupies area as small as possible while remaining high performance, is imperatively needed. Finite impulse response (FIR) digital filter is one of the most widely used fundamental devices performed in DSP systems, ranging from wireless communications to video and image processing. Furthermore, when narrow transition band characteristics are required, the much higher order in the FIR filter is unavoidable. For instance, a 576-tap digital filter is used in video ghost canceller for broadcast television, which reduces the effect of multi-path signal echoes. On the other hand, parallel and pipelining processing are two techniques used in DSP applications, which both can be exploited to reduce the power consumption. Parallel processing applied on FIR digital filter can either increase the throughputs for high-speed processing or reduce the power consumption of the original sequential filter by lower supply voltage. Hence, there have been several architectures for parallel FIR digital filter proposed in the past. However, for symmetric convolutions, linear phase digital FIR filter, these proposed architectures are not beneficial in terms of hardware consumption. In this dissertation, new parallel FIR digital filter architectures which can save significant hardware cost by exploiting the inherent nature of symmetric convolutions, namely linear phase digital FIR filter, are presented. This dissertation is mainly divided into four chapters. In chapter one, some prerequisites as the background related to parallel finite impulse response (FIR) digital xi filter design and implementation are introduced, including conventional parallel FIR digital filter architectures, parallel FIR digital filter structures based on fast FIR algorithm (FFA), previously proposed architectures for parallel FIR filter, maximum absolute difference (MAD) quantization algorithm, canonic signed digit (CSD) representation and CSD multipliers for constant multiplications, are introduced and reviewed. In chapter two, the proposed parallel FIR digital filter structures for symmetric convolutions of even length are presented, in which the complexity and experimental results are analyzed and compared with FFA-based parallel FIR digital filter and other previously proposed structures. In chapter three, the proposed parallel FIR digital filter architectures for symmetric convolutions of odd length are presented, in which the complexity and the benefit of structures are analyzed and compared with FFA-based parallel FIR digital filter and other previously proposed structures The last chapter, chapter four, gives the summary and the conclusion of the proposed parallel linear-phase FIR digital filter.
Ph.D. in Electrical Engineering, December 2011
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Title: PARTICLE FILTERING ESTIMATION APPROACH IN ADVANCED DIGITAL COMMUNICATION SYSTEMS
Creator: Huang, Lun
Date: 2013, 2013-05
Description: The ever-increasing volume of users and the demand for more communication services bring about many advanced modulation and demodulation...
Show moreThe ever-increasing volume of users and the demand for more communication services bring about many advanced modulation and demodulation technologies which are developed to increase the spectrum efficiency and cope with challenging transmission conditions in digital communications. However, it is difficult to improve the performance of those traditional modulation and demodulation approaches without increasing transmit power and lowering spectrum efficiency. This thesis studies the application of powerful Particle Filtering methods to the problems associated with the interference cancellation, equalization, demodulation, and decoding of the signals over communication channel. In this thesis, theoretic models of using particle filtering approaches in digital communications are investigated, and several specific algorithms and schemes are considered as applications of the theoretic models. First, the application of particle filtering in delayed decision feed-back sequence estimation equalization is addressed. The particle filtering approach is then introduced to an efficient particle filtering receiver for inter-carrier interference cancellation and demodulation of M-ary modulated signals in OFDM/OFDMA system under time-variant Rayleigh fading channels. Subsequently, an efficient sequential Monte Carlo (SMC) demodulation approach for Polynomial Phase Modulation (PPM) is discussed. The interference cancellation and demodulation algorithm for MIMO-PPM scenario is then derived. The analysis of performance and computational complexity for SMC particle filtering approach is also provided. Comprehensive simulation results confirm that the proposed sequential Monte Carlo particle filtering approaches have better performance than the conventional methods.
PH.D in Electrical Engineering, May 2013
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Title: EXPANDING FAITH-BASED ORGANIZATIONS’ ADAPTATION OF STREAMING TECHNOLOGY
Creator: Johnson Winston, Patty D.
Date: 2011-07-18, 2011-05
Description: In the field of technical communication there exist few studies that specifically address faith-based organizations’ use of communication...
Show moreIn the field of technical communication there exist few studies that specifically address faith-based organizations’ use of communication technology. The purpose of this dissertation was to show how these organizations can expand their use of streaming technology by using principles and practices that are common in technical communication. This was addressed in three phases. First, a review of the relationship between religion and media was conducted. It revealed that faith-based organizations are early adaptors of communication technology. Communication technology is used to widely broadcast their organizational missions, tenets and goals. By accomplishing these tasks, faith-based organizations seek to educate and reinforce cultural norms, images, and belief systems among their adherents and attract new members. Second, an examination of theories and instructional practices found in technical communication was conducted. It was determined that adapting a learning-centered approach to instruction can be applied to a distance education model for faith-based education. Third, faith-based websites were analyzed to determine types and current uses of communication technology. It was established that most of the organizations that offer educational courses do not conduct them online, even if they already use streaming media for other purposes. The findings suggest that faith-based organizations’ use of streaming technology for educational purposes is an area of inquiry that should be further explored by technical communicators. Technical communication provides a rich array of disciplines from which to draw, such as Instructional Design, Information Architecture, and Usability.
Ph.D. in Technical Communication, May 2011
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Title: TECHNOLOGY INTEGRATION IN SCIENCE EDUCATION: A STUDY OF HOW TEACHERS USE MODERN LEARNING TECHNOLOGIES IN BIOLOGY CLASSROOMS
Creator: Gnanakkan, Dionysius Joseph
Date: 2017, 2017-07
Description: This multiple case-study investigated how high school biology teachers used modern learning technologies (probes, interactive simulations and...
Show moreThis multiple case-study investigated how high school biology teachers used modern learning technologies (probes, interactive simulations and animations, animated videos) in their classrooms and why they used the learning technologies. Another objective of the study was to assess whether the use of learning technologies alleviated misconceptions in Biology documented by American Association for the Advancement of Science. The sample consisted of eight teachers: four rural public school teachers, two public selective enrollment school teachers, and two private school teachers. Each teacher was followed for two Units of instruction. Data collected included classroom observations, field notes, student assignments and tests, teacher interviews, and pre-and post-misconception assessments. Paired t-tests were done to analyze the pre-post test data at a significance level of 0.05 and the qualitative data was analyzed using the constant comparative method. Each case study was characterized and then a cross-case analyses was done to find common themes across the different cases. Teachers were found to use the learning technologies as a tool to supplement instruction to visualize abstract processes, collect data, and explore abstract concepts and processes. Teachers were found to situate learning, use scaffolding and questioning and make students work in collaborative groups. The genetics, photosynthesis, and evolution misconceptions were better alleviated than cellular respiration. Student work that was collected demonstrated a superficial understanding of the concepts under discussion even when they had misconceptions. The teachers used the learning technologies in their classrooms for a variety of reasons: visual illustrations, time-saving measure to collect data, best way to collect data, engaging and fun for students and the interactive nature of the visualization tools and models. The study’s findings had many implications for research, professional development, teacher education, teaching practice, administrators, and learning technology developers. More detailed research within similar school settings (public, charter, and private) is needed to verify the common findings across the different cases in this study. An implication is that learning technology integration could be modeled with instructional scaffolds and questioning and incorporating higher order thinking tasks. Learning technology developers should consider the collaborative learning groups while developing these technologies.
Ph.D. in Science Education, July 2017
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Title: FINITE ELEMENT ANALYSIS OF HIGH HEAT LOAD DEFORMATION AND MECHANICAL BENDING CORRECTION OF A BEAMLINE MIRROR FOR THE APS UPGRADE
Creator: Goldring, Nicholas
Date: 2017, 2017-07
Description: The impending Advanced Photon Source Upgrade (APS-U) will introduce a hard x-ray source that is set to surpass the current APS in brightness...
Show moreThe impending Advanced Photon Source Upgrade (APS-U) will introduce a hard x-ray source that is set to surpass the current APS in brightness and coherence by two to three orders of magnitude. To achieve this, the storage ring light source will be equipped with a multi-bend achromat (MBA) lattice [1]. In order to fully exploit and preserve the integrity of new beams actualized by upgraded storage ring components, improved beamline optics must also be introduced. The design process of new optics for the APS-U and other fourth generation synchrotrons involves the challenge of accommodating unprecedented heat loads. This dissertation presents an ex-situ analysis of heat load deformation and the subsequent mechanical bending correction of a 400 mm long, grazing-incidence, H2O side-cooled, reflecting mirror subjected to x-ray beams produced by the APS-U undulator source. Bending correction is measured as the smallest rms slope error, σrms, that can be resolved over a given length of the heat deformed geometry due to mechanical bending. Values of σrms in the <0.1 µrad regime represent a given mirror length over which incident x-ray beams from modern sources can be reflected without significant loss of quality [2, 3]. This study assumes a perfectly flat mirror surface and does not account for finish errors or other contributions to σrms beyond the scope of thermal deformation and elastic bending. The methodology of this research includes finite element analysis (FEA) employed conjointly with an analytical solution for mechanical bending deflection by means of an end couple. Additionally, the study will focus on two beam power density profiles predicted by the APS-U which were created using the software SRCalc [4]. The profiles account for a 6 GeV electron beam with second moment widths of 0.058 and 0.011 mm in the x- and y- directions respectively; the electron beam is passed through a 4.8 m long, 28 mm period APS-U undulator which produces the x-ray beam incident at a 3 mrad grazing angle on the flat mirror surface for both cases. The first power density profile is the most extreme case created by the undulator at it’s closest gap with a critical energy of 3 keV (ky=2.459); the second profile is generated for the case in which the undulator is tuned to emit at 8 keV (ky=1.026). The 3 keV case is of particular interest as it represents one of the most intense peak heat loads predicted to be incident on first optics at the APS-U. The FEA results revealed that the deflection due to the 3 keV heat load yields a 10.9 µrad rms slope error over the full mirror length. The projected correction via the elastic bending of the substrate yields a 0.10 µrad σrms within the center longitudinal 300 mm. The FEA also predicts that the 8 keV heat load deflection can be corrected to a σrms of 0.11 µrad within the center 300 mm from 1.50 µrad over the entire length. Attempts to optimize the end couple to correct over the entire 400 mm mirror length were unable to resolve the heat load deflection rms slope error to within a < 0.1 µrad value for either case. However, if a larger corrected surface is required, a longer mirror can be implemented so as to absorb the heat load of a larger beam than necessary which can then be cut by an aperture to the desired size and energy range.
M.S. in Physics, July 2017
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Title: COORDINATED DRIVING IN CONNECTED AND AUTONOMOUS VEHICLE SYSTEM -- OPTIMAL ADVANCE LANE CHANGE ZONES AND COORDINATED PLATOON CAR FOLLOWING CONTROL
Creator: Gong, Siyuan
Date: 2017, 2017-07
Description: The connected and autonomous vehicle (CAV) system enables countless innovative coordinated driving approaches, such as coordinated lane change...
Show moreThe connected and autonomous vehicle (CAV) system enables countless innovative coordinated driving approaches, such as coordinated lane change and car-following in microscopic CAV control, and coordinated rounding and parking in macroscopic traffic flow guidance, which will improve the performance of our transportation system by enhancing traffic mobility, providing safe driving environment and reducing fuel consumption. Since the lane change and car-following behavior are indicated as crucial factors of traffic safety and efficiency, this dissertation focuses on developing the coordinated driving schemes in microscopic control and operation of lane change and car-following maneuvers. In particular, I develop an lane change zone optimization strategy and the coordinated platoon car-following control for a pure CAV platoon and a mixed platoon (i.e. mixed with human-drive vehicles and CAVs) respectively. This dissertation first explore the management strategy of the mandatory lane change near a two-lane highway off-ramp by optimizing the location of advance warning. The proposed approach considers that the area downstream of the advance warning includes two zones: the green and yellow zones corresponding to their respective most like lane change maneuvers. An optimization model is proposed to search for the optimal green and yellow zones. Traffic flow theory such as Greenshield model and shock wave analysis are used to analyze the impacts of the S-MLC and D-MLC maneuvers on the traffic delay. Numerical experiments indicate that the proposed optimization model can identify the optimal location to set the advance MLC warning nearby an off-ramp so that the traffic delay resulting from lane change maneuvers is minimized, and the corresponding capacity drop and traffic oscillation can be efficiently mitigated. Then, this research develops a novel car-following control scheme for a platoon of connected and autonomous vehicles on a straight highway. The platoon is modeled as an interconnected multi-agent dynamical system subject to physical and safety constraints. A constrained optimization based control scheme is proposed to ensure an entire platoon’s transient traffic smoothness and asymptotic dynamic performance. This dissertation develops dual based distributed algorithms to compute optimal solutions with proven convergence. Furthermore, the asymptotic stability of the unconstrained linear closed-loop system is established. These stability analysis results provide a principle to select penalty weights in the underlying optimization problem to achieve the desired closed-loop performance for both the transient and the asymptotic dynamics. By the motivation that CAVs and human-drive vehicles will co-exist on the road for a long period in the near future, the third part of this dissertation extends the pure CAV coordinated platooning control to the mixed flow environment. By integrating the Newell car-following model, a real-time curve matching algorithm is implemented to calibrate the ca-following model and anticipate the movement of human-drive vehicle by the real-time trajectory data. The constrained MPC are developed for each CAV platoon, considering their movement interaction through the human-drive vehicle platoon. Furthermore, this study provide a modified dual based distributed algorithm to improve convergence speed of the primal problem for the dual based distributed algorithm in Chapter 4. Several requirements of the penalty weights selection are provided by stability analysis under the unconstrained conditions. The numerical experiments based on field data will be conducted to illustrate the effectiveness and efficiency of the proposed the solution approach and the platoon control schemes.
Ph.D. in Civil Engineering, July 2017
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Title: INTEGRATED PLANNING OF BEV PUBLIC FAST-CHARGING STATIONS
Creator: Gong, Lin
Date: 2015, 2015-12
Description: This thesis proposes a multi-layer strategy and an abstract map method to achieve an integrated planning of public fast-charging stations to...
Show moreThis thesis proposes a multi-layer strategy and an abstract map method to achieve an integrated planning of public fast-charging stations to charge certain number of lightduty battery electric vehicles in a given geographic region under its existing environment, aiming to improve application of electric vehicle in the studied region and finally enhance social welfare in a long term by optimally locating public fast-charging stations and assigning their installed capacities to maximize the possibility of effectively charging battery electric vehicles, as well as to minimize the infrastructure cost and mitigate possible negative impacts on the transportation system and the electric power system. In the first layer of this multi-layer strategy, the conditions of the transportation system are considered, analyzed and mathematically modeled, while in the second layer, based on the former layer, the conditions of the electric power system are incorporated. Then in the third layer, an integrated planning of public fast-charging stations is achieved by combining both the transportation system's and the electric power system's conditions. From the first to the last layer, a case is studied in each layer to test the idea, method and also the mathematical model which is built by the MILP method. These works are based on an abstract road network map which is rooted in the actual map of a representative geographic region. After the optimal results based on the abstract map are obtained, they will be mapped back to the actual map of the representative geographic region. Therefore, the ideas, methods and solutions studied in this thesis aiming to achieve an integrated planning of public fast-charging stations to charge battery electric vehicles are able to be applied in practice.
M.S. in Electrical Engineering, December 2015
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Title: Graphical methods in reinforced concrete design
Creator: Klein, Samuel, Greifenhagen, E. O.
Date: 2009, 1909
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/graphicalmethods00klei
Thesis (B.S.)--Armour Institute of Technology

Title: DUAL-BASED APPROXIMATION ALGORITHMS FOR MULTIPLE NETWORK DESIGN PROBLEMS
Creator: Grimmer, Benjamin
Date: 2016, 2016-05
Description: We study a variety of NP-Complete network connectivity problems. Our pri- mary results come from a novel Dual-Based approach to approximating...
Show moreWe study a variety of NP-Complete network connectivity problems. Our pri- mary results come from a novel Dual-Based approach to approximating network de- sign problems with cut-based linear programming relaxations. This approach gives a 3=2-approximation to Minimum 2-Edge-Connected Spanning Subgraph that is equivalent to a previously proposed algorithm. One well-studied branch of network design models ad hoc networks where each node can either operate at high or low power. If we allow unidirectional links, we can formalize this into the problem Dual Power Assignment (DPA). Our Dual-Based approach gives a 3=2-approximation to DPA, improving the previous best known approximation of 11=7 1:57. Another standard network design problem is Minimum Strongly Con- nected Spanning Subgraph (MSCS). We propose a new problem generalizing MSCS and DPA called Star Strong Connectivity (SSC). Then we show that our Dual-Based approach achieves a 1.6-approximation ratio on SSC. As a result of our Dual-Based approximations, we prove new upper bounds on the integrality gaps of these problems. For completeness, we present a family of instances of MSCS (and thus SSC) with integrality gap approaching 4=3.
M.S. in Computer Science, May 2016
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Title: HARDWARE/SOFTWARE CO-DESIGN PARTITIONING ALGORITHM FOR MACHINE VISION APPLICATIONS
Creator: Gonnot, Thomas
Date: 2017, 2017-05
Description: Advancements in FPGA technologies now allows the implementation of machine vision using hardware component rather than processors for...
Show moreAdvancements in FPGA technologies now allows the implementation of machine vision using hardware component rather than processors for increased efficiency. The combination of hardware and software implementations, however, can provide even more efficient results by combining the advantages of both technologies. This leads to the problem of partitioning the machine vision algorithms between hardware and software. The hardware/software partition problem is NP-hard, which means that a solution to the problem can be checked in polynomial time, but the time to find the solution is not predictable. Automated methods based on a genetic algorithm or discrete particle swarm optimization algorithm allow a designer to implement computer vision algorithms without concerns for the hardware/software partitioning. Their reliance on randomness to explore different partitioning selections, however, means that the optimum result might not be reached and that the processing time cannot be predicted. This dissertation introduces a model for image processing and computer vision algorithms in a set of elementary blocks, each of which is assigned one or more configuration. This configuration can be either hardware or software and is linked to the corresponding resource utilization and performance. A procedure is also introduced to allocate the different blocks to either hardware or software, and a cost function is defined to evaluate the relevance of the generated design. The implementation of the model and procedure allows for the partitioning of any image processing in polynomial time by checking various implementations and selecting the optimum solution. This thesis includes two test cases used to test the efficiency of the method. The shift-invariant features transform is used to demonstrate the viability of the partitioning results on an algorithm containing multiple image convolution operations in parallel. The neural network, on the other hand, is used to demonstrate the performances of the procedure when machine vision algorithm contains many blocks. Finally, this dissertation present a set of machine vision applications, such as object tracking, object recognition, optical character recognition, facial recognition, and visually impaired assistance. The proposed model and procedure could be included in the design flow of hardware/software co-design tools and provide a library of image processing blocks ready to be implemented. This would allow image processing and computer vision designers would be able to implement any algorithm efficiently in hardware/software co-design without the need to know how to partition it.
Ph.D. in Electrical Engineering, May 2017
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Title: DESIGN AND DEVELOPMENT OF A DRIVETRAIN TEST BENCH FOR ELECTRIC AND HYBRID ELECTRIC VEHICLES
Creator: Niu, Geng
Date: 2013, 2013-12
Description: Due to continuously increasing price of petroleum and related environmental issues, the automotive industry is more focus on the fuel...
Show moreDue to continuously increasing price of petroleum and related environmental issues, the automotive industry is more focus on the fuel efficient and low energy consumption. Electric-Drive vehicles (EDV), such as Electric Vehicles (EV), Hybrid Electric Vehicles (HEV) and Plug-in Hybrid Electric Vehicles are expected to replace the regular energy consumption vehicles and be the next generation of regular means of transportation. Low emission is one feature that will have significant effect on environment issue and less regular energy consumption is another feature that will reduce the speed of the global depletion of the world’s oil. Furthermore EDVs have relatively higher efficiency because of lots of research on the topology exploration, fuel efficiency maximization strategies, power conversion technologies, and integration into the current power grid. EDVs have mechanical system and electrical system and both of them works concurrently. So the best way to test EDV is that design a detailed drivetrain test bench for performance evaluation EVs and HEVs. This emulation test bench can be a lab setup that researchers can do an EDV program testing and also can serve as an educational tool that will provide a real observation for engineering students to realize EVs and HEVs design and how it works. The test bench has two separate sections, one is for performance evaluation all-electric-vehicle and the other is for performance evaluation series hybrid electric vehicle. These two setups use same motors, servomotor and controllers. HEV drivetrain is consist of two 6 HP axial flux permanent magnet (AFPM) brushless machines and two servomotors (PMSM) made by Kollmorgen. EV drivetrain is consist of one 6 HP axial xii flux permanent magnet (AFPM) brushless machine and one permanent magnet servomotors made by Kollmorgen. The purpose of this work is to design and develop a detailed test bench for performance evaluation of both EVs and HEVs, especially for undergraduate students and graduate students understanding the structure and design of EDVs. Labview is used as the interface to monitor all the components of the whole system. Through the EV test bench, student can observe how the all-electric-vehicle works and compare with traditional vehicles. HEV test bench can give student a vision observation of series hybrid electric vehicle. From these two test benches, students can realize the different operation modes of EDVs and observe the direction of the power flow of EDVs. [1-2] Finally, student can program different drive cycles to the servomotor and then test the cycles by running the test bench.
M.S. in Electrical Engineering, December 2013
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Title: ADVANCES IN VEHICLE-TERRAIN INTERACTION MODELING FOR SMALL, RIGID-WHEELED VEHICLES OPERATING ON DEFORMABLE TERRAIN
Creator: Meirion-griffith, Gareth
Date: 2012-04-22, 2012-05
Description: This thesis presents advances in the eld of terramechanics, the study of ve- hicle mobility performance, for small, rigid-wheeled vehicles...
Show moreThis thesis presents advances in the eld of terramechanics, the study of ve- hicle mobility performance, for small, rigid-wheeled vehicles operating on deformable terrain. Speci cally, the thesis proposes new models for vehicle performance model- ing through the development of novel pressure-sinkage equations. The semi-empirical equations of terramechanics, rst developed by Bekker in the 1950s, couple vehicle mobility systems and terrain geotechnical properties to yield an understanding of the manner in which traction is developed o -road. This is important because on de- formable terrain mobility is often limited not by the vehicle's torque or power, but by the strength of the terrain and its ability to support locomotion. Classical terramechanics models have proven to be instrumental in the design, modeling, and operation of large, man-driven vehicles for applications such as agri- cultural, military, and commercial transport. However, these models are not appro- priate for vehicles with wheels less than approximately 50 cm in diameter [MGS11a] [SMGSM08] [RBC02]. This is a critical problem because of the increasing prolifer- ation of small, robotic vehicles. In particular, space agencies such as the National Aeronautics and Space Administration (NASA), the Japanese Aerospace Exploration Agency (JAXA), and the European Space Agency (ESA) have shown great interest in the application of terramechanics to planetary exploration rover mobility. At the inception of the author's research, several independent sources had noted the limited accuracy of classical terramechanics models for small-wheeled vehi- cles. However, an understanding of the cause of these inaccuracies was absent. This thesis provides an understanding of these inaccuracies, their cause, and a solution. Using laboratory experiments, fi eld test data, theoretical development, and vehicle simulation, this thesis proposes a modi fied terramechanics framework for predicting small, rigid-wheel traction.
Ph.D. in Mechanical and Aerospace Engineering, May 2012
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Title: Glycerol and spent lye clarification
Creator: Parrot, Raymond D.
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/glycerolspentlye00parr
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 39

Title: SLIDING MODE CONTROL OF CONVERTERS WITH AN INDEPENDENT NEUTRAL POINT
Creator: Ghosh, Somsubhra
Date: 2017, 2017-07
Description: With the increasing footprint of renewable energy, the drive towards a cleaner environment has consistently pushed forward the development of...
Show moreWith the increasing footprint of renewable energy, the drive towards a cleaner environment has consistently pushed forward the development of power electronics based power converters. While the basic principles of operating the power electronics in these power converters have been very effective in providing for a very efficient system, new topologies and advanced control strategies enable us to achieve a still higher efficiency, simplification and help us overcome some of the fundamental problems encountered in operation. One of the fundamental requirements of the power electronic converters is that they require a significantly large output capacitors. it is necessary to remove ripples in the rectified AC voltage. Numerous approaches have been presented in the past to overcome these issues including the addition of a ripple compensator to a conventional H-Bridge rectifier as well as using one leg of the H-Bridge itself as a neutral leg. A new controller; based on sliding mode has been proposed here to a neutral leg topology as well as the conventional H-Bridge topology of a single-phase power converter. In case of a rectifier, the ripple energy is separated and directed towards the lower split capacitor present at the neutral leg so that the upper split capacitor may have very small ripples while in case of an inverter the lower capacitor actually acts as an independently controlled DC source. all the while the capacitance is kept to be very small. The control of the two legs in the rectifier is performed independently granting the controller an extra degree of freedom and an easier extrapolation to the 3-phase implementation. The controller operates the power electronic switches to regulate the input grid current and achieve unity power factor as well as to maintain a stable DC bus voltage removing the need for any other power factor correction circuit.
M.S. in Electrical Engineering, July 2017
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Title: BARRIERS TO TREATMENT FOR INNER-CITY CHILDREN WITH DISRUPTIVE BEHAVIOR DISORDERS AND THEIR FAMILIES: AN EVALUATION OF FACTORS THAT INFLUENCE TREATMENT PARTICIPATION
Creator: Gibson, Lynda L.
Date: 2015, 2015-12
Description: Despite the prevalence of disruptive behavior diagnoses in inner-city children, research findings have consistently shown that African...
Show moreDespite the prevalence of disruptive behavior diagnoses in inner-city children, research findings have consistently shown that African-Americans and individuals from inner-city populations tend to utilize mental health services significantly less than other racial and income groups. The primary aim of this study was to identify child, parent, and contextual factors that predicted duration oftreatment in a manualized family therapy intervention for disruptive behavior disorders in children and adolescents. Findings from this study revealed that higher levels of treatment participation were significantly predicted by increased severity of externalizing symptoms and lower levels ofstress present within the home. These fmdings indicate that families whose children have more severe problems are more likely to stay in treatment and that treatment participation may be enhanced by offering case management to families to reduce their levels of stress.
M.S. in Psychology, December 2015
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Title: A NOVEL FIXED DISPLACEMENT ELECTRIC-HYDRAULIC HYBRID (EH2) DRIVETRAIN CONCEPT FOR CITY VEHICLES
Creator: Sun, Yingguang
Date: 2013, 2013-07
Description: With growing emphasis on energy independence and environmental issues, alternative energy vehicles, especially Electric Vehicles (EV), Hybrid...
Show moreWith growing emphasis on energy independence and environmental issues, alternative energy vehicles, especially Electric Vehicles (EV), Hybrid Electric Vehicles (HEV) and Plug-in Hybrid Electric Vehicles (PHEV) have received significant attention. Though these solutions can have significant an impact on the environment, economy and efficiency, some challenges still exist in the widespread acceptance of EVs and HEVs. Some issues include low power density of the battery and low battery durability caused by frequent charging and discharging. This can be especially significant for city use owing to typical drive cycles. In order to address this problem, this work proposes a novel electric-hydraulic hybrid (EH2) drivetrain for PHEVs, HEVs and EVs. An EH2 drivetrain is comprised of an electric traction motor and a hydraulic system that uses a combination of hydraulic pump, motor and accumulator. All the components and their operation theory are introduced in this work. In the proposed system, a hydraulic accumulator is used for energy storage during the regenerative braking process. The energy stored in the accumulator will be released to the hydraulic motor during the power assistance process [1]. In this drivetrain, two 6 HP axial flux permanent magnet (AFPM) brushless machines are selected as the traction motor and hydraulic drive. This kind of motor is very suitable for electric vehicles, pump, valve control, fans, etc. due to its pancake shape, compact structure and high torque density [2]. To validate the proposed design, the mathematical model of the hydraulic energy storage system is built in Matlab/Simulink environment and the simulation results are given both for the regenerative braking process and power assistance process. The xiv models of the axial flux permanent magnet brushless machines and its drive system are also built in the Matlab/Simulink. The simulation results are compared with the experimental testing results from the motor test bed built in the lab. Preliminary simulation and experimental results show in the regenerative braking process, 5332 J energy is stored in the accumulator and the energy conversion efficiency is 64.39%. In power assistance process, all the energy stored in the accumulator is released and the vehicle accelerates from 0 m/s to 5.2 m/s. The energy conversion efficiency is 50.71%. These results prove that the hydraulic energy storage system can be used in power assistance and energy storage. The charging and discharging time is very short compared with other energy storage systems. More importantly, the stored energy can reduce the number of times the battery is charged and discharged. In this way the battery size can be reduced and the battery life can be extended. The parallel hydraulic-electric configuration is proved to be a promising solution towards energy storage and power assistance for electric vehicles. Finally, the electric and hydraulic components have been implemented on a go-kart setup built in the lab for future complete drivetrain testing. From the conducted research, it can be concluded that successful implementation of this concept can lead to a wider acceptance of electric vehicles.
M.S. in Electrical Engineering, July 2013
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Title: CAPACITY ANALYSIS OF MULTI-RADIO MULTI-CHANNEL (MR-MC) WIRELESS NETWORK
Creator: Li, Hongkun
Date: 2012-11-15, 2012-12
Description: The multi-radio multi-channel (MR-MC) networking provides a generic computing platform for a wide range of next-generation wireless networks,...
Show moreThe multi-radio multi-channel (MR-MC) networking provides a generic computing platform for a wide range of next-generation wireless networks, e.g., wireless mesh networks based on the IEEE 802.16, 4G cellular networks based on the long term evolution (LTE), and cognitive radio networks based on the dynamic spectrum sharing. Multiple radio interfaces and channels allow more flexible network configuration to achieve higher network capacity. However, the capacity of the MR-MC networking is not well studied due to the lack of effective tool addressing the complex interactions of the channel assignment and radio interface allocation problem. Moreover, how to efficiently utilize multiple interfaces and channels is unexplored. Generally, we have the four main contributions in this work. 1) an efficient methodology is proposed to compute the optimal capacity of MR-MC network and the concept of critical set is revealed. 2) two sufficient conditions are developed for the flow assignment, which can be constructed and verified in distributed manner. Both conditions achieve a provable portion of the optimal capacity region. 3) a novel framework and efficient algorithms are developed for the dynamic network control in the MR-MC network. 4) a new routing metric is proposed to consider both delay and interference for path selection, and a routing protocol is designed correspondingly. Specifically, we originally construct a new multi-dimensional conflict graph (MDCG) to describe all the interference relationship in the MR-MC network. Based on MDCG, we formulate a multi-commodity flow (MCF) problem augmented with maximal independent set (MIS) constraint to compute the optimal capacity, so that the optimal capacity planning in MR-MC networks can be transformed from integer programming regime to linear programming regime. We further provide the new concept of critical MIS set, and estimate the upper bound of the size of critical MIS set. Therefore, a heuristic algorithm is designed to systematically compute those MISs, which are more likely to be involved in critical set. Moreover, we develop the sufficient conditions for the flow rate assignment, which achieve viii a provable portion of the optimal capacity region, termed as efficiency ratio. These sufficient constraints could be constructed and verified in the distributed and localized manner. We develop new method to compute the efficiency ratio for each sufficient condition by exploring the disruptively different geometric property of MR-MC networks compared with single radio single channel network. Then we develop a new framework to systematically study the resource allocation problem considering the dynamic network control in the MRMC network. The framework not only facilitates the formulation of throughput-optimal scheduling for the MR-MC network, but also allows us optimally solving the joint resource allocation problem, including routing, channel/interface assignment, flow allocation and scheduling. At last, a new routing metric is proposed to consider not only the transmission delay also queuing delay. In addition, in the MR-MC context, the inter-flow interference and intra-flow interference are taken into account. An AODV-based routing protocol is designed to implement the new metric.
PH.D in Electrical and Computer Engineering, December 2012
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Title: RATE AND TEMPERATURE DEPENDENT MECHANICAL BEHAVIOR AND MODELING OF AL-CU ALLOY SYSTEM
Creator: Tran, Henry
Date: 2011-12-19, 2011-12
Description: Deformation of materials in army applications such as fragment impact, projectile penetration and air blast/shock waves involves high strain...
Show moreDeformation of materials in army applications such as fragment impact, projectile penetration and air blast/shock waves involves high strain rates, large strains, high pressures and rapid changes in temperature, where overall performance ultimately depends on the evolution of flow stress, failure initiation and propagation, generally in the form of adiabatic shear banding (ASB), under these severe loading conditions. Some of 2XXX series aluminum-copper (Al-Cu) alloys such as Al 2519-T87 have been successfully used in Lightweight Armored Vehicles in the U.S. Army because of their good ballistic properties. More recently, an Al-Cu-Mg-Ag alloy designated as Al 2139-T8 has emerged in 2004 as a strong candidate in damage critical applications with higher strength and high-strain-rate performance than its predecessors. Its better ballistic performance is believed to be due to the underlying microstructure. The objective of this study is to investigate mechanical and deformation behavior of Al-Cu material system to develop a fundamental understanding of the effect of composition and microstructural features on overall dynamic behavior. To this end, a systematic approach is adopted to start from single crystal Al and move towards polycrystalline Al, then Al-Cu, and all the way to Al-Cu-Mg-Ag system. Current thesis study constitutes a part of this ongoing work and, therefore, only covers single crystal Al ([001] and [111] directions), polycrystalline Al, and Al-0.1%Cu. Compressive mechanical response of each one of these materials has been investigated in a wide strain rate range that covers quasi-static (from 10-4 to 100 s-1) and dynamic (from 102 to 104 s-1) strain rate regimes. With the exception of single crystal Al (because of limited supplies), additional experiments have been conducted at 120C and 220C within the same strain rate range to understand their thermal softening behavior in varying strain rate regimes. Based on and driven by experimental results, a modified Johnson-Cook model is proposed to describe their rate and temperature dependent constitutive behavior. Finally, in order to investigate susceptibility of these materials and varying microstructures to adiabatic shear localization the two specimen geometries, namely “top hat” and “shear-compression specimen”, have been evaluated. In this evaluation, emphasis is placed upon reliable quantification of strain field within the gage section. Shear compression specimen has been identified to be the best candidate to use in future studies that will explore the tendency of each one of these materials to failure by adiabatic shear banding.
M.S. in Mechanical and Aerospace Engineering, December 2011
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