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Title: WasteLESS Modular Housing: FINAL_BOARDS_landscape_BrodmarkleEmerson
Creator: Emerson, Melissa
Date: 2012-05-02, 2012-05
Description: This project aimed to create efficient housing for the average American with the ability to customize their home to their own needs, lifestyle...
Show moreThis project aimed to create efficient housing for the average American with the ability to customize their home to their own needs, lifestyle, and aesthetics. In addition, the feasibility of pre-fabricated portions of the home made this more realistic in terms of cost and the quickness of its construct-ability for each potential home owner.
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Title: IMPROVEMENT OF HUMAN FEATURE DESCRIPTORS FOR PEDESTRIAN DETECTION
Creator: Zarshenas, Mohammadamin
Date: 2015, 2015-05
Description: This thesis investigates the effect of feature descriptor selection on pedestrian detection process. Pedestrian detection, the problem of...
Show moreThis thesis investigates the effect of feature descriptor selection on pedestrian detection process. Pedestrian detection, the problem of recognizing, locating and tracking humans in videos has become a challenging task in computer vision area. Video surveillance and advanced driver assistance systems (ADAS) are few appli- cations of pedestrian detection. At the very rst stage of the pedestrian detection system, feature descriptors are created to describe the texture, shape and color in- formation of the pedestrian candidate. These extracted features, acts as an input to develop and test a pedestrian classi er Feature descriptor techniques su er from di erent kinds of problems such as illumination variation of the dataset, pedestrian pose di erences and noise in the region of interest (ROI). To overcome the problem of illumination change, depth maps, can be exploited due to their robustness under various illuminations. Considering real-time nature of the targeted applications, another important challenge for the feature descriptor technique is the computational complexity and also the resulting dimension of the feature space. In the initial part of this thesis, several feature descriptor techniques are ex-plored. In the primary part of this thesis work, two critical stages of pedestrian detec- tion are improved, depth map computation stage and the feature descriptor creation stage. Two novel fast techniques to compute depth maps are proposed for the depth- map computation stage; three newly proposed new descriptors are proposed which work on depth channel or a combination of depth and color to adaptively overcome the illumination variation problem while still maintaining low dimensional feature space. These methods are found to outperform existing state-of-the-art descriptors and with exceptionally low computational complexity.
M.S. in Electrical Engineering, May 2015
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Title: Sustainable High-Rise Building at Nanjido Park in Seoul
Creator: Kwon, Osung
Date: 2011-08-08, 2011-07
Description: n/a
M.Arch., July 2011

Title: COGNITIVE IMPAIRMENT, DEPRESSION, AND INFLAMMATION IN OLDER HEMATOPOIETIC STEM CELL TRANSPLANT RECIPIENTS
Creator: Fong, Wing Man
Date: 2015, 2015-07
Description: Cancer is a common disease that increases in prevalence with age; it predominantly affects individuals over the age of 55. Cancer can be...
Show moreCancer is a common disease that increases in prevalence with age; it predominantly affects individuals over the age of 55. Cancer can be associated with a number of health complications due to the disease itself and/or its treatments such as higher risk of infection, anemia, fatigue, and cognitive dysfunction. Risks of developing these complications increase with age. Despite the increased vulnerability among older individuals, the existing literature and clinical trials show a disproportionately low enrollment rate for this population. This study aimed to provide to a mechanism-based understanding of cognitive impairment in older patients with hematologic malignancy who were scheduled to undergo hematopoietic stem cell transplantation (HSCT). Emerging evidence suggests that a significant portion of older persons with cancer demonstrate cognitive impairment prior to HSCT, and that cognitive deficits prior to HSCT are related to post-transplant complications. Hence, the goals of the study were to characterize cognitive impairment in older cancer patients prior to HSCT, and to examine the relations between cognitive impairment, depression, and inflammation. Sixty-one patients with hematologic malignancy participated in the current study and were administered a comprehensive neuropsychological assessment. Results showed that 50% of the sample was impaired on verbal memory. Correlation analyses revealed a significant association between depression and attention, with inflammation found to be a non-significant mediator. Possible alternative explanations with implications for future research and limitations of the study were discussed.
Ph.D. in Psychology, July 2015
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Title: PART BASED PEDESTRIAN DETECTION BY FEATURE SYNTHESIS
Creator: Kuang, Guozheng
Date: 2014, 2014-07
Description: Detecting humans in images or video sequences is a challenging task owing to their variable appearance and the wide range of poses that they...
Show moreDetecting humans in images or video sequences is a challenging task owing to their variable appearance and the wide range of poses that they can adopt. The first and most important factor in achieving satisfactory detection result is robust feature set that allows the human form to be discriminated clearly, even in cluttered background under difficult illumination. Many researchers endeavored to find a robust and light descriptor for human body for over twenty years. Some of them have presented enlightening approaches and promising performance, such as histogram of oriented gradients [1], purposed in 2006 and speeded fast robust feature [2] purposed in 2008 are both outstanding holistic features that give a nice description of pedestrian. Recently a rising trend in part-based approaches pedestrian classification aims to deal with occlusion occasions happen frequently in real world urban street scenarios. By dividing the pedestrian’s body image into several parts relaxes the detector’s emphasis on the whole pedestrian body. Even when part of pedestrian’s body cannot be seen in the image, the rest part of the body will still contribute to the classification.
M.S. in Electrical Engineering, July 2014
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Title: FROM EXPLORATION TO RATIONAL DESIGN OF SELECTIVE PROPANE DEHYDROGENATION CATALYSTS
Creator: Hu, Bo
Date: 2015, 2015-12
Description: Light olefins, e.g., ethene and propene, are important building blocks of chemical industry for the production of fuels, polymers, lubricants...
Show moreLight olefins, e.g., ethene and propene, are important building blocks of chemical industry for the production of fuels, polymers, lubricants and other fine chemicals. Due to the rapidly increasing production of shale gas, conversion of small alkanes in the shale gas, e.g., ethane and propane, to their corresponding olefins via alkane dehydrogenation could be an important industrial process. This thesis has focused on exploring the novel single site heterogeneous catalysts for selective alkane dehydrogenation and investigating the general principles of rational catalyst design to achieve a better performing (e.g., more active, more stable, highly selective) dehydrogenation catalyst. Based on the observed reactivity of ZnO for olefin hydrogenation and activity of Zn-ZSM-5 catalysts for alkane activation, catalytic properties of isolated Zn2+ were first explored for propane dehydrogenation. The 3-coordinate Zn in single site Zn/SiO2 catalyst was demonstrated to be the catalytically active species that was highly selective for the generation of propene by propane dehydrogenation. DFT calculations revealed that slow β-hydride elimination of alkyl intermediates limited the overall activity of single site Zn/SiO2 catalyst. Thus, single site Co/SiO2 was also prepared in order to take the advantage of fast β-hydride elimination. The higher activity of single site Co/SiO2 emphasized the potential of transition metals for alkane dehydrogenation, and propane dehydrogenation reactivity of transition metals was further explored by investigating single site Fe/SiO2 catalyst. By comparing with metallic Fe nanoparticles and bulk phase Fe oxides catalysts, the 3-coordinate single site Fe2+ was also suggested to be the catalytically active species for selective propane dehydrogenation. However, the catalytic activity of single site Fe/SiO2 catalyst was lower than that of Zn/SiO2. Such result suggested heterolytic cleavage of C-H bonds was slow for transition metals, e.g., Co and Fe, due to their weak Lewis acidity, and it may mitigate the advantages gained in rapid β-hydride elimination. An exploration of ligand effects for improving heterolytic cleavage over single site heterogeneous catalysts was performed. The strength of metal oxygen bond governed by ligand electron donating effects and ligand basicity were found to be the critical chemical descriptors for a facile heterolytic cleavage. Those observed principles of ligand effects would lead to a new strategy of rational catalyst design for a superior dehydrogenation catalyst.
Ph.D. in Chemistry, December 2015
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Title: CONTRIBUTIONS TO ALGORITHMIC MATROID PROBLEMS
Creator: Huang, Jinyu
Date: 2015, 2015-07
Description: In this thesis, we obtain several algorithms for problems related to matroids, a structure that generalizes the concept of linear independence...
Show moreIn this thesis, we obtain several algorithms for problems related to matroids, a structure that generalizes the concept of linear independence in a vector space and an acyclic subgraph structure in a graph. Matroids have been widely applied in combinatorial optimization, graph theory, coding theory and so forth. Specifically, our results include: In this thesis, we present a constant-competitive online algorithm of the matroid secretary problem for the partition matroids without information of the partition and for the paving matroids. We also introduce the multi-objective matroid secretary problem that extends the matroid secretary problem, in which the weight function is a k-vector w = [w1, · · · , wk]. We show a constant competitive algorithm of the multiobjective matroid secretary problem for the uniform matroids and for the paving matroids. Since bases of a matroid generalize many important combinatorial structures, many counting problems can be expressed as a problem that counts the number of bases of a matroid. An efficient approximate counting algorithm can be designed provided that a rapidly-mixing Markov chain that samples bases of a matroid can be constructed. Let Φ(G) be the conductance of the base-exchange graph G. Matroid- Expansion Conjecture (1989, Mihai and Vazirani) states that Φ(G) ≥ 1 for any base-exchange graph G of a matroid, which implies an FPRAS (fully-polynomial randomized approximation scheme) for counting the number of bases of a matroid. We use λ2, the second smallest eigenvalue of L, the discrete Laplacian matrix of G, to prove the Matroid-Expansion Conjecture for any paving matroid, for any balanced matroid, and for the direct sum of a paving matroid with a balanced matroid. A maximum linear matroid parity set is called a basic matroid parity set, if its size is the rank of the matroid. We show that determining the existence of a common base (basic matroid parity set) for linear matroid intersection (linear matroid parity) is in NC2, provided that there are polynomial number of common bases (basic matroid parity sets). For graphic matroids, we show that finding a common base for matroid intersection is in NC2, if the number of common bases is polynomial bounded. We also give a new RNC2 algorithm that finds a common base for graphic matroid intersection. Finally, we prove that if there is a black-box NC algorithm for PIT (Polynomial Identity Testing), then there is an NC algorithm to determine the existence of a common base (basic matroid parity set) for linear matroid intersection (linear matroid parity).
Ph.D. in Applied Mathematics, July 2015
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Title: A BOUNDARY INTEGRAL METHOD FOR SOLVING THE BRINKMAN'S EQUATION IN 3-DIMENSIONAL FLOW
Creator: Gundaboina Harish, Aditya Kiran
Date: 2014, 2014-12
Description: In this paper, we consider the boundary integral equation (BIE) corresponding to the Brinkmans equation. We compute the velocities of the...
Show moreIn this paper, we consider the boundary integral equation (BIE) corresponding to the Brinkmans equation. We compute the velocities of the interacting particles when the point-wise forces acting on them are known. We assume a ctitious ow point inside the bead and eliminate the double-layer in the BIE. This BIE is now numerically solved by covering the surface of the bead by two overlapping patches and de ning their partition of unity. We then discuss the e ect of the overlapping of the patches on the results. We develop a second-order accurate numerical method for the BIE. ix
M.S. in Applied Mathematics, December 2014
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Title: THE IMPACT OF ORGANIC LOAD ON THE MINIMAL LEVEL OF CHLORINE NEEDED TO PREVENT E. COLI O157:H7 CROSS-CONTAMINATION DURING WASHING OF FRESH-CUT LETTUCE
Creator: Zhou, Chao
Date: 2015, 2015-05
Description: Fresh-cut vegetables are no longer considered low risk due to their association with an increasing number of E. coli O157:H7 outbreaks. E....
Show moreFresh-cut vegetables are no longer considered low risk due to their association with an increasing number of E. coli O157:H7 outbreaks. E. coli O157:H7 contamination in fresh produce originated on farm can spread during postharvest washing. Industry and government guidelines have suggested the use of chemical disinfectants such as sodium hypochlorite in wash water to prevent microbial cross-contamination and have recommended that wash water disinfectants be monitored. However, specific standards regarding the levels of chlorine needed have yet to be established. The goal of this study was to determine the minimal effective level of chlorine needed to prevent E.coli O157:H7 cross-contamination during post-harvest washing of fresh-cut lettuce with wash water containing different levels of organic load and to evaluate the way to monitor the organic load in wash water by correlating measurements of Total Organic Carbon (TOC) with turbidity measurements. Eight grams of cut romaine lettuce inoculated with 8 log cfu/g of E. coli O157:H7 were washed with 800 g of uninoculated lettuce in 40 L of sterile tap water at 3℃ for 2 min. Washing trials were performed in water with different levels of organic load (with the addition of 0, 3, 6, 12, or 30 g of lettuce juice powder) and at different levels of chlorine treatment (0 - 40 ppm of sodium hypochlorite). The degree of cross-contamination was determined by measuring the presence of E. coli O157:H7 in the wash water and uninoculated lettuce after washing. Wash water samples were also analyzed for total/free chlorine, turbidity, and TOC. In the absence of chlorine, E. coli O157:H7 transfer occurred at all levels of organic load and resulted in the contamination of wash water and uninoculated lettuce at levels of 3.61 ± 0.13 log cfu/ml and 3.34 ± 0.23 log cfu/g, respectively. Without the addition of lettuce juice powder, cross-contamination was prevented in wash water containing 5 ppm of sodium hypochlorite. With the addition of 3 g of lettuce juice powder, transfer of E. coli O157:H7 was observed when the washing run was conducted with 5 ppm of sodium hypochlorite but was prevented when the level of sodium hypochlorite was raised to 10 ppm. With the addition of 30 g of lettuce powder, 40 ppm of sodium hypochlorite was needed to prevent cross-contamination. It was difficult to have an accurate determination of the residual free chlorine level as it continued to decrease during the washing run. Measurements of the organic load of wash water are needed to determine the effective level of sanitizer required to prevent microbial cross-contamination during postharvest washing of fresh-cut produce. TOC is a good indicator of organic load in wash water, but it took hours to get results. Turbidity measurement only takes minutes and it correlated well with TOC, indicating that turbidity has the potential to indicate the organic load in wash water.
M.S. in Food Safety and Technology, May 2015
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Title: INCORPORATING SAFETY HARDWARE PERFORMANCE FUNCTIONS INTO RISK-BASED HIGHWAY SEGMENT SAFETY EVALUATION
Creator: Dao, Hoang
Date: 2012-07-23, 2012-07
Description: Nowadays, State transportation agencies have developed management systems as analytical tools to improve roadway safety. Management systems...
Show moreNowadays, State transportation agencies have developed management systems as analytical tools to improve roadway safety. Management systems dealing with traffic safety hardware including traffic signs, signals, lighting, pavement markings, guardrails, barriers, and crash cushions have been identified as an important and non-separable part of safety management. As statistics shown, approximately 42,000 deaths on American roads due to vehicle crashes with one of the main causes being in lack of adequately performed safety hardware. It is easily realized that along the time the performance of traffic safety hardware decreases. State transportation agencies have spent millions of dollars on maintenance and replacement of safety hardware in each year. However, most of the agencies have not developed robust methodologies to assess impacts of traffic safety hardware on safety performance and optimize safety hardware investments. This study began with a literature review of safety performance functions and useful service lives of different types of safety hardware. Based on findings of the literature review and case studies conducted nationwide, this research proposes a new risk-based methodology for computing the safety index that assesses impacts of safety hardware conditions on vehicle crashes. The methodology is applied to a computational study by using 5- year data from 2002 to 2006 on 193 highway segments in Ozaukee County, Wisconsin. The results are compared with Empirical Bayesian adjusted crash estimates via statistical tests in order to validate the proposed methodology. Finally, it discusses future directions for continuing refinements of the proposed methodology.
M.S. in Civil Engineering, July 2012
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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: 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: MATERNAL-FETAL ATTACHMENT: CONSTRUCT EXAMINATION AND DEVELOPMENT OF A NEW MEASUREMENT SCALE
Creator: Hedrick, Laura
Date: 2015, 2015-05
Description: There has been a recent resurgence of interest in studying maternal-fetal attachment (MFA), and MFA has been correlated with several important...
Show moreThere has been a recent resurgence of interest in studying maternal-fetal attachment (MFA), and MFA has been correlated with several important variables (e.g., parenting behavior and infant attachment). However, there are differing definitions of MFA, and, as a result, widely varying questionnaires have been developed to assess it. Each of these instruments has demonstrated major weaknesses, such as inadequate operational definitions and theoretical rationales, poor reliability or validity, barriers to practical application, and inconsistent results in correlational studies. The purpose of the present study was twofold. The first aim was to examine the latent factors that underlie the existing measures of MFA in order to better understand the potential components of the construct. The second aim was to develop a new measure with greater practical applicability, more thorough and empirically-sound development procedures, and improved reliability and validity relative to existing instruments. All items from extant questionnaires were pooled with novel items based on an interview measure. This bank of 112 items was administered to a diverse sample of 292 women in their second and third trimesters of pregnancy. Exploratory factor analytic (EFA) procedures revealed underlying factors relating to perceived personhood of the fetus or richness of the mother's perceptions of her fetus, affective components, future orientation, focus on the fetus across domains, and caregiving sensitivity. Four different EFA approaches resulted in three viable models for a new measure with interpretable factor structure, acceptable face validity, good internal consistency, and some favorable results in initial concurrent validity analyses. Directions for future research are discussed.
M.S. in Psychology, May 2015
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Title: COMMUNITY ENGAGEMENT AND COMMUNITY RESPONSE OF FIRST TIME CODE CONTRIBUTORS ON GITHUB
Creator: Heston, Matthew
Date: 2014, 2014-05
Description: We collect data for 13,383 rst time code contributions from 45 projects on the website GitHub and analyze behavior of developers before...
Show moreWe collect data for 13,383 rst time code contributions from 45 projects on the website GitHub and analyze behavior of developers before submitting code as well as community response to code contributions. Our ndings di er from previous research on open source software communities and social theories of learning in communities of practice. We nd most users do not participate in GitHub peripheral activities before submitting code changes. We also nd that community response to these submitted code changes is a poor predictor of whether or not the code is accepted.
M.S. in Information Architecture, May 2014
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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: NONLINEAR SIMULATIONS OF MULTI-VESICLE DYNAMICS
Creator: Hamiilton, Caleb
Date: 2015, 2015-07
Description: Vesicles in biology are closed forms of membranes. The dimensions of vesicles can vary in terms of surface area and enclosed volume. Examples...
Show moreVesicles in biology are closed forms of membranes. The dimensions of vesicles can vary in terms of surface area and enclosed volume. Examples range from small organelles to large cell bodies which all play a variety of resource transportation roles in biological systems. Research from the fields of chemistry and physics helps mathematical modeling by providing the mechanisms behind certain observed morphologies. Mathematical models and methods for simulating vesicle dynamics have produced accurate numerical solutions to verify experimental data and can be used to design new experiments that lead to more discoveries. The most researched case has been a single vesicle under shear flow. However, recent numerical and experimental results consider extensional flows on a single vesicle and hydrodynamic interactions among multiple vesicles. This thesis extends work on hydrodynamic interactions between vesicles in viscous fluid. We investigate numerically cases with multiple vesicles relaxing in asymmetrical configurations, time-dependent flow with more oscillation, and stochastic dynamics. Subjecting vesicles to these various cases reveals sensitivity to initial conditions such as distance and relative orientation. The effects from adding more vesicles are: increased time before equilibrium for the relaxation tests, and distributive wrinkling dynamics for the extensional flow tests. In stochastic cases, there are similar wrinkling distributions. However, initial conditions like distance and orientation have less important effects when competing with influence from thermal fluctuations. Additionally, in the presence of other vesicles under extensional flow, a vesicle may change the number and amplitude of wrinkles it would have experienced alone.
M.S. in Applied Mathematics, July 2015
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Title: EFFICACY OF PULSED LIGHT TECHNOLOGY FOR THE INACTIVATION OF SALMONELLA ENTERITIDIS PT 30 ON ALMOND KERNEL SURFACE
Creator: Harguindeguy, Maite
Date: 2016, 2016-05
Description: Almond surfaces can be contaminated with pathogens such as Salmonella. Traditional thermal processing technologies used for inactivation of...
Show moreAlmond surfaces can be contaminated with pathogens such as Salmonella. Traditional thermal processing technologies used for inactivation of Salmonella on almonds can adversely impact the quality. Therefore, there is a need to investigate the efficacy of alternative technologies for inactivation of Salmonella on almonds without adversely affecting the quality. Pulsed light, a novel technology, can potentially be used to achieve this. Therefore, this study evaluated the efficacy of three pulsed light systems (operating at 1.8, 3, or 100 Hz) under various electrical input powers (1000, 1250 and 1500 W) and treatment times for inactivation of Salmonella Enteritidis PT 30 on almond surfaces. More than 4-log reduction was achieved at different treatment conditions for each of the control units. For instance, a 160 s treatment at 1500 W (100 Hz system) resulted in a 4.3 log CFU/almond reduction. Whereas, similar reductions were achieved in a shorter time with the lower frequency systems (1.8 or 3 Hz). Reductions of 4.6 and 5.9 log CFU/almond were achieved after 80 and 100 s treatment, respectively with the 1.8 Hz system (1250 W). Similarly, a 100 s treatment with the 3 Hz system (1000 W) resulted in a reduction of 4.7 log CFU/almond. Statistical analysis showed that the effect of equipment, treatment time, and electrical power input were significant (p<0.05). The D-values of 1.8, 3, and 100 Hz systems were 0.24, 0.53 and 0.73 min, respectively at 1500 W. In general, lower frequencies resulted in increased inactivation in shorter time. This can be attributed to the higher instantaneous power at lower frequencies. Similar trends were observed at other electrical input powers. The D-values found using pulsed light treatment are lower than the conventional dry heat treatment ones. Also, minimal color change was observed for treated almonds. These results indicate that pulsed light is efficacious for decontaminating almond surfaces within a relatively short time.
M.S. in Food Process Engineering, May 2016
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Title: CHILD TEMPERAMENT AND PARENTING BEHAVIOR AT AGE 5: DO THEY PREDICT CHILD COPING AT AGE 6?
Creator: Hwang, Maria D’aniello
Date: 2014, 2014-07
Description: Coping has been shown to be related to many positive outcomes in children, including better psychological adjustment, positive social...
Show moreCoping has been shown to be related to many positive outcomes in children, including better psychological adjustment, positive social relationships and higher achievement. Additionally, coping abilities in childhood and adolescence can serve as risk or protective factors for psychopathology. Both parenting and child temperament have been shown to be related to child coping; however, these variables have never been examined simultaneously. The transition from kindergarten to grammar-school is considered to be important because children must learn to adjust to this critical, more structured environment. As a result, it is important to determine what factors contribute to adaptive coping at the time when children begin formal school. The aim of this study was to: (a) examine the relationship between child negative affect (NA), effortful control (EC), parenting variables (support/scaffolding, support/engagement, and hostility/coercion), and child coping; and (b) to determine if parenting moderates the effects of temperament on adaptive coping. Participants included 796 (391 males and 405 females) children and their primary caregivers. Children were assessed at ages 5 and 6 years. NA and EC were assessed by parent-report with the Child Behavior Questionnaire. EC also was assessed with an observer-rated task, Gift Delay, which measures the child’s ability to delay a prepotent response, and with two subtests from the NEPSY; Knock and Tap, and Statue. Parenting variables (support/engagement and hostility/coercion) were assessed by parent-report with the Parenting Behavior Inventory and through an observation task, which was assessed by a factor-analyzed composite of variables rated during the National Institute for Child Health and Human Development 3-Boxes Task (support/scaffolding). Coping adaptability was assessed using the Early Childhood Coping Puppet Interview. Results of hierarchical regression analyses indicated that NA, EC, support/scaffolding, support/engagement, and hostility/coercion were not related to child coping adaptability. There also was no evidence of moderation of the relationship between temperament and coping by parenting. Post hoc analyses indicated that for males, lower SES was related to more adaptive coping. Implications of these findings and suggestions for further research are discussed.
Ph.D. in Psychology, July 2014
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Title: REVISITING THE URBAN BLOCK IN THE LIGHT OF CLIMATE CHANGE A CASE STUDY OF BUDAPEST
Creator: Gal, Csilla Viktoria
Date: 2014, 2014-07
Description: Since the beginning of the twentieth century, the urban block configuration of free-standing buildings has been deemed superior to other built...
Show moreSince the beginning of the twentieth century, the urban block configuration of free-standing buildings has been deemed superior to other built forms, as it provided the necessities of modern healthy living: sunlight and fresh air. In light of climate change, the dissertation aims to reevaluate these long held beliefs and to reintroduce microclimate as an urban design consideration. The study takes four metropolitan block typologies of Budapest as cases to clarify the microclimate influence of key urban design parameters by means of a numerical simulation study. The effects of built form, orientation, vegetation and facade properties are evaluated for a typical summer day. The cases are assessed on the basis of diurnal potential air and mean radiant temperatures within the urban canopy layer. Numerical modeling is performed by ENVI-met and analysis is conducted with MATLAB. The findings indicate that built form and vegetation are key factors governing the microclimate. During the day, intraurban cool island develops between dense configurations and in tree-shaded urban canopies. Orientation is decisive in configurations with large open spaces, where east-west alignment corresponds with peak radiant and air temperatures. Apart from albedo, facade properties have little effect on the microclimate. The rise of air temperature with facade albedo is the outcome of canopy floor heating, resulting from the increased ratio of reflected shortwave radiation. A short-term field experiment was conducted in Budapest to complement the numerical simulation study and to evaluate ENVI-met. The measurement campaign utilized six air temperature and humidity loggers. Additionally, wind speed, air temperature and humidity were recorded at the pedestrian level during an anticyclonic period. In courtyards, thermal stratification developed by day with cool island intensities up to 7 C. In the case of open configurations, neither cool island, nor stratification was observed. The comparison of measured and predicted air temperatures revealed the strengths and weaknesses of the numerical model. In general, predicted temperatures had a decreased diurnal range with maximum values systematically underestimated. ENVI-met also failed to reproduce the thermal stratification in courtyards. Despite these shortcomings, the predicted trends and the relative microclimate differences between the configurations agreed with observations reasonably well.
Ph.D. in Architecture, July 2014
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Title: THE LENGTH-TENSION CURVE OF FLIGHT MUSCLE IN MANDUCA SEXTA
Creator: Wang, Geng
Date: 2015, 2015-05
Description: The synchronous indirect flight muscle (DLM1) is located in the thorax of the Hawk moth, Manduca sexta. It has the potential to be a model...
Show moreThe synchronous indirect flight muscle (DLM1) is located in the thorax of the Hawk moth, Manduca sexta. It has the potential to be a model system for cardiac muscle because both muscles have similar length-tension curves and they have similar passive properties (Tu & Daniel, 2004). An important and valuable property of the muscle is the temperature gradient between dorsal and ventral muscles which have a corresponding functional gradient between them. The functions of dorsal and ventral muscle appear to be regulated by the temperature gradient and changes in the phase of activation (N. T. George, Sponberg, & Daniel, 2012). Very little is known, however, about its other physiological properties. Here I measured the relation between tetanic tension and sarcomere length in chemical skinned dorsal and ventral muscle in order to further characterize the properties of the two muscle parts. Analysis of the results showed similarities and differences in the length of thick and thin filaments, maximum force, and rates of force generation between dorsal and ventral muscles. Maximal force was also plotted as a function of temperature in order to inquire into the physiological changes of muscle at various temperatures. The potential of DLM1 to be a model system for some aspects of cardiac muscle research was supported by the results of this study. The hypothesis that functions of dorsal and ventral muscle is regulated by the temperature gradient and changes in the phase of activation also was verified.
M.S. in Biology, May 2015
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