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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: 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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Title: Industrial illumination
Creator: Arenberg, Albert Lee
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/industrialillumi00aren
Thesis (B.S.)--Armour Institute of Technology, 1917 B.S. in Electrical Engineering, 1917

Title: SCALABLE INDEXING AND SEARCHING ON DISTRIBUTED FILE SYSTEMS
Creator: Ijagbone, Itua
Date: 2016, 2016-05
Description: Scientific applications and other High Performance applications generate large amounts of data. It’s said that unstructured data comprises...
Show moreScientific applications and other High Performance applications generate large amounts of data. It’s said that unstructured data comprises more than 90% of the world’s information [IDC2011], and it’s growing 60% annually [Grantz2008]. The large amounts of data generated from computation leads to data been dispersed over the file system. Problems begin to exist when we need to locate these files for later use. For small amount of files this might not be an issue but as the number of files begin to grow as well as the increase in size of these files, it becomes difficult locating these files on the file system using ordinary methods like GNU Grep [8], which is commonly used in High Performance Computing and Many-Task Computing environments. It is as a result of this problem that we have chosen this thesis to tackle the problem of finding files in a distributed system environment. Our work leverages the FusionFS [1] distributed file system and the Apache Lucene [10] centralized indexing engine as a fundamental building block. We designed and implemented a distributed search interface within the FusionFS file system that makes both indexing and searching the index across a distributed system simple. We have evaluated our system up to 64 nodes, compared it with Grep, Hadoop, and Cloudera, and have shown that FusionFS’s indexing capabilities have lower overheads and faster response times.
M.S. in Computer Science, May 2016
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Title: INACTIVATION OF MURINE NOROVIRUS AND MS2 COLIPHAGE DURING FREEZE-DRY DEHYDRATION OF CONTAMINATED STRAWBERRIES
Creator: Wang, Xueyan
Date: 2013, 2013-07
Description: Human norovirus (HuNoV) is the major causative agent of foodborne acute gastroenteritis in the US and worldwide. A 2012 norovirus outbreak...
Show moreHuman norovirus (HuNoV) is the major causative agent of foodborne acute gastroenteritis in the US and worldwide. A 2012 norovirus outbreak that was associated with frozen strawberries has led to more than 11,000 illnesses in Germany. Freezedrying, a common process used to preserve berries, has been questioned for its effectiveness of norovirus inactivation. In our study, the survival of MS2 coliphage and murine norovirus-1 (MNV-1), surrogates of HuNoV, on inoculated strawberries were evaluated during a 24hr freeze-dry dehydration process with and without radiant heat. Fresh strawberries were 7 mm-thickness sliced, virus-inoculated, 1hr frozen, and 24hr freeze-dried. Freeze-drying of inoculated berries with the temperature ranging from 0 to 40°C was studied with continuous recording of the temperatures once every 20 min. Infectious MNV-1 was quantified using a Raw 264.7 cell culture plaque assay. The quantification of MS2 was conducted using a double agar plaque assay. The average recovery of MS2 coliphage from berry slices by an elution protocol developed in the study was 97% ± 27% based on the inoculum as 100%. Only 57% ± 11% of MNV was recovered from berry slices using the identical elution protocol. Approximately half of the recoverable population (either MS2 or MNV-1) became undetectable after 24hr cold storage, the final average recovery being 46% and 29% for MS2 and MNV-1 respectively. Radiant heat was found to accelerate the reduction of MS2 up to 2.56 logs reduction per sample in the process. The overall reduction of MS2 was about 3 logs as maximum after 24hr freeze-drying. Regression analysis illustrated a significant correlation between MS2 log reduction and radiant heat applied. The x regression formula suggested that an increase of one degree Celsius in radiant heat during the 24hr freeze-drying would increase the log reduction of MS2 on berries by 0.044 log. The reductions of MNV on berries after the 24hr freeze-drying ranged from 0.85 to 1.82 logs. Via ANOVA analysis, MNV reduction on berries with radiant heat ≥20°C was significantly greater than heating at 10°C or without heat (~0°C), p<0.05. The overall maximum reduction of MNV on berries after the 24hr-process, therefore, was >2 logs. Although radiant heat inactivated MNV during the freeze-drying process, the inactivation of MNV by heat was less efficient than that of MS2. These data may be helpful in designing processes to control viral contaminants during freeze-drying of virus-contaminated berries.
M.S. in Food Safety and Technology, July 2013
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Title: Improvement of Sheridan road in Glencoe
Creator: Walther, Ralph A., Dawson, M., Sturtevant, R. W.
Date: 2009, 1909
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/improvementofshe00walt
Thesis (B.S.)--Armour Institute of Technology

Title: FATIGUE, FRACTURE, AND CRACK GROWTH BEHAVIOR OF FIVE CANDIDATE STEELS FOR WIND TOWER APPLICATION
Creator: Tsosie, Henrietta R.
Date: 2011-08, 2011-07
Description: Fatigue, fracture toughness, and crack propagation tests were performed on five candidate steels for wind tower applications. Normally, these...
Show moreFatigue, fracture toughness, and crack propagation tests were performed on five candidate steels for wind tower applications. Normally, these steels are ordered to meet ASTM A572/A709 Grade 50 or EN 10025-2 Grade S355 in the normalized condition. Five steels with varying carbon content and alloy additions focusing on niobium and vanadium content are investigated. Two of the five steels are in the normalized condition to check the EN 10025-2 requirement while the rest are in the as-rolled condition. Fatigue tests were performed to determine the endurance limit using a constant amplitude loading at a constant load ratio. Fracture toughness testing using the J􀀀 integral method was performed to determine the critical fracture energy, Jc. This value is then converted to the critical plain strain stress intensity factor if requirements are met. Three fracture toughness tests were performed for each material at room temperature using a C(T) specimen. Crack propagation tests were performed to determine the Paris constants using a contoured double cantilever beam specimen. The steels with niobium give better results in fatigue and displayed smaller grain diameters than the steels with vanadium. The fatigue results for the low carbon steel with niobium are comparable to another HPS steel. Overall, the low carbon steel with niobium provides better toughness, fatigue resistance, and weldability than the steels that are normalized to meet the EN 10025-2 requirement for wind tower plates.
M.S. in Materials Science and Engineering, July 2011
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