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Title: PARAMETRIC COST ESTIMATION MODEL OF INTEGRATED REACTOR VESSEL UNDER MODULAR CONSTRUCTION WITHIN A FACTORY ENVIRONMENT
Creator: Chen, Xuan
Date: 2013, 2013-12
Description: High initial cost is one of the major barriers for the nuclear power industry. Small modular reactors (SMR) may be a solution to this problem...
Show moreHigh initial cost is one of the major barriers for the nuclear power industry. Small modular reactors (SMR) may be a solution to this problem because they have a much smaller financial barrier. In this thesis, parametric cost estimation modeling studies have been performed for the SMR integrated reactor vessel (IRV) under a factory environment. Based on different prior fabrication experiences, three scenarios have been studied, and the corresponding possible manufacturing costs of the entire IRV and its subcomponents have been estimated. To explore the cost allocation, the total cost has been divided into five cost contributors: labor, material, tooling labor, tooling replacement, and other. The results have been analyzed and discussed.
M.S. in in Mechanical, Material and Aerospace Engineering, December 2013
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Title: COMPARISON BETWEEN TWO CHITIN-PURIFIED PRO-DEATH PROTEINS IN MITOCHONDRIA TARGETING ANALYSIS
Creator: Yeap, Xin Yi
Date: 2011-04-19, 2011-05
Description: Bax protein belongs to the Bcl-2 family. It is pro-apoptotic and the most common form is Bax α. When a cell receives death stimuli, Bax...
Show moreBax protein belongs to the Bcl-2 family. It is pro-apoptotic and the most common form is Bax α. When a cell receives death stimuli, Bax protein will oligomerize and target to mitochondria. Another isoform of Bax called Bax 2, which has lost exon 2 and has a frame shift mutation, is verified to be more potent in inducing apoptosis than Bax α. Here, we would like to understand more about Bax 2 mitochondria targeting ability compared to the more common Bax α form. We first set up a cell-free system which contained purified Bax protein and purified mitochondria. The mitochondrial binding protein was identified using fractionation and Western blot with Bax isoformspecific antibodies. Integration of Bax protein into the mitochondrial membrane was determined using the alkaline stripping method. The results suggest that the majority of Bax α targeted and integrated into the mitochondria membrane, while the majority of Bax 2 did not target to mitochondria in the cell-free system. This may suggest that Bax 2 might need additional help from certain cytosol components such as co-factors to target to mitochondria or that Bax 2 induces cell death through a mechanism other than mitochondrial targeting.
M.S. in Biology, May 2011
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Title: MOLECULAR AND GENETIC ENGINEERING STUDIES OF VITREOSCILLA HEMOGLOBIN
Creator: Chen, Yang
Date: 2014, 2014-05
Description: Biodesulfurization is a promising field that can be applied to the processing of crude oil for removing dibenzothiophene (DBT) and its...
Show moreBiodesulfurization is a promising field that can be applied to the processing of crude oil for removing dibenzothiophene (DBT) and its derivatives. A thermophilic bacterial strain Paenibacillus naphthalenovorans (32O-Y) was found to metabolize DBT as sole sulfur source. Another thermophilic strain Paenibacillus apiaries (32O-W) which cannot utilize DBT, however, was found to increase the desulfurization activity of 32O-Y in mixed 32O-Y+W culture in minimal-DBT medium at temperatures between 45 and 50 °C. In order to increase the desulfurization activity of these strains, we genetically engineered strain 32O-Y to express Vitreoscilla hemoglobin (VHb). VHb is the first hemoglobin found in bacteria and has been used to increase the growth and product yields various cells. The VHb gene (vgb) was successfully cloned into shuttle vector pNW33N. 32O-Y was successfully transformed with pNW33N-vgb while 32O-W was not. Compared to untransformed 32O-Y, 32O-Y[pNW33N-vgb] grew slower and reached a lower maximum OD600 when cultured in minimal-DBT medium at 45 °C. However, the Gibbs assay showed that VHb expression in 32O-Y increased its desulfurization activity by 18%. Thus, VHb can help 32O-Y metabolizing DBT while it might not promote growth. A series of high temperatures cultures need to be conducted to select an even more thermophilic strain which can fulfill the 60 °C requirement of industrial process. The VHb mutant (vgbM3) was also studied, which was previously found correlated with increased growth of E. coli DH5α, compared with the effect of wild type VHb. The effect that the mutant amino acids in VHbM3 was determined. Plasmid pUC- vgbM3 was obtained and successfully transformed to DH5α. After sequencing, two copies of vgbM3 were found in the plasmid. In order to study only one copy of vgbM3, x primers were designed for amplification. Fragment vgbM3 was successfully inserted into vector pUC18, followed by successful transformation into DH5α. Cell free extract was obtained from strains DH5α, DH5α[pUC8:16] and DH5α[pUC18-vgbM3] for CO-difference assay. As expected, DH5α expressed no hemoglobin. DH5α[pUC8:16] expressed wild type hemoglobin at 20 nmol/gm wet weight, while DH5α[pUC18-vgbM3] expressed mutant hemoglobin at 4 nmol/gm wet weight. Oxygen dissociation constant determination of VHbM3 will be the next step.
M.S. in Biology, May 2014
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Title: NETWORK CODING BASED COOPERATIVE PEER-TO-PEER REPAIR IN WIRELESS NETWORKS
Creator: Liu, Yu
Date: 2012-07-11, 2012-07
Description: Multimedia Broadcast/Multicast Service (MBMS) in cellular networks has emerged recently as a promising distribution model to provide rich...
Show moreMultimedia Broadcast/Multicast Service (MBMS) in cellular networks has emerged recently as a promising distribution model to provide rich content distribution where a batch of content is broadcast to a large number of peers simultaneously. However, ensuring efficient error-free message delivery in such a scenario is a challenge, since packet loss is inevitable due to the time-varying nature of wireless transmissions, and the server is probably overwhelmed by floods of individual retransmission requests from peers. Cooperative Peer-to-Peer (P2P) information repair has been proposed to mitigate the packet loss among peers during Base Station (BS) broadcast, by allowing peers to cooperate on information exchange among themselves, rather than asking the BS to rebroadcast the lost packets for the peers. Network Coding, a fairly recent transmission paradigm with the potential network throughput improvement and high reliability advantage, has been widely recognized as a promising information dissemination approach for wireless networks. In this research, we study the network coding based cooperative P2P information repair in wireless networks. We first propose our initial work - a connected dominating set (CDS) based P2P information repair (PPIR) protocol with network coding which utilize the clustering idea, to minimize the total repair latency as well as alleviate the congestion and burden of BS’s downlink channels. Then the decision making problem for P2P repair with densely distributed nodes is studied and two approaches are provided. Later on, the NC based P2P information repair protocol with tunable parameter (NC-PIRTP) which evolved from PPIR protocol is proposed to further reduce transmission collisions and total repair latency. At last, P2P information repair under mobile network environment with pedestrian speed is studied and three efficient protocols are illustrated which are suitable to different specific cases. Extensive simulation results are provided for performance evaluation and comparisons, and to demonstrate the effectiveness and efficiency of our proposed protocols in terms of the total repair latency. Furthermore, an analytical model is developed, based on which theoretical results are derived. These results validate our protocol models and provide useful protocol design guideline for the cooperative P2P information repair problem in wireless networks.
Ph.D. in Electrical Engineering, July 2012
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Title: SUSTAINABLE NEW CITY VAN, TURKEY
Creator: Dursun, Kevser Pinar
Date: 2013, 2013-07
Description: While the negative effects of rapid urbanization is threatening cities and the environment, being more conscientious about the current...
Show moreWhile the negative effects of rapid urbanization is threatening cities and the environment, being more conscientious about the current problems and future expansions of the cities and developing new visions and strategies for new cities is crucial. In this proposal, the aim is to develop a prototype of a sustainable new city in Turkey. Design area is called Carpanak, at the east shore of Lake Van. It is in the north of Van, the biggest city in the Eastern Anatolia district of Turkey. Eastern Anatolia is a mountainous district with a severe climate. The region is less developed than the other regions in every aspect. Severe climate and lack of job opportunities caused outmigration from this region to big cities or onshore regions with more developed industries. A city with sufficient infrastructure, efficient energy solutions, green areas, well-designed transportation, economic viability, and open social structure will help reverse the migration and rescue Eastern Anatolia from being abandoned. It is hoped that the design decisions, ideas, and the research can be applied as an outline to other underdeveloped areas in Turkey.
M.S. in Architecture, July 2013
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Title: URBAN RETROFIT OF THE HISTORICAL CITY OF AHMEDABAD, INDIA
Creator: Patel, Chanakya Dineshbhai
Date: 2012-11-26, 2012-12
Description: Most great cities of today originally started as small settlements on the banks of rivers. Ahmedabad, founded in year 1411 AD by emperor Ahmed...
Show moreMost great cities of today originally started as small settlements on the banks of rivers. Ahmedabad, founded in year 1411 AD by emperor Ahmed Shah indeed has a claim for thriving in all aspects of life for the past six centuries. Established as a small military settlement on the dry and sandy north Gujarat plains on the bank of river Sabarmati, Ahmedabad today is fifth largest city and seventh largest metropolitan of India. Geographically the Sabarmati River divides the city of Ahmedabad into two segments. Within each side of the city there are two distinct images, urban west and historic east. It could be stated that the historic district of city must now hold its position as the center both geographically and economically considering the overall metropolitan area of Ahmedabad. With rapid urbanization, the historic district is overlapped by today’s fast paced life and urbanity resulting a steady loss of its heritage and greater than that, a sense of place. This thesis proposes a conservation and reconstruction model for the historic district of Ahmedabad addressing the most fundamental issues of economic viability and sustainability. The main challenge driving this thesis is how to retrofit the historic district so that it matches the urbanity of 21st century along with keeping its historic character intact. The initial process is to assemble background observations and research that will provide an understanding of the concepts required for retrofitting the historic district of Ahmedabad. It is hopeful that the ideas and architectural process can also be a framework to be applied on other historic cores that have been neglected and suppressed by today’s urbanity and especially in Asian countries.
M.S. in Architecture, December 2012
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Title: VIDEO FEATURE DETECTION AND MATCHING FOR STRUCTURE FROM MOTION SYSTEM
Creator: Yang, Guojun
Date: 2015, 2015-05
Description: With the improvements in sensor technologies and image processing algorithms, computer vision has become a major tool for robots to recognize...
Show moreWith the improvements in sensor technologies and image processing algorithms, computer vision has become a major tool for robots to recognize and gauge their surroundings. For instance, the Kinect sensor can be used as an excellent depth camera for indoor navigation. However, there exist situations that need recognition and spatial interpretation of the environment using limited hardware resources. The Kinect is not suitable for outdoor use, while LIDAR is too large and expensive to be installed on an autonomous miniature surveillance drone. Therefore, the use of a single camera is the only feasible option for many embedded applications. To perform SfM (structure from motion) by using single camera is challenging due to the complexity of 3D mapping. Feature detection and mapping is the very fist step to perform SfM. To be more specific, matched feature points are used as anchors cross images or frames. Without such matched feature points, most SfM method will not be able to generate reliable results; moreover, instead of using frames from videos as inputs, most feature detectors and matching strategies are designed for SfM applications using images as inputs. Therefore, this thesis will discuss how to detect feature points from video and match them effectively. Image projection and SfM fundamentals will be introduced in this thesis as well.
M.S. in Electrical Engineering, May 2015
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Title: THE MOLECULAR MECHANISM OF BAXΔ2-MEDIATED CELL DEATH AND ITS TISSUE DISTRIBUTION IN COLON CANCER
Creator: Zhang, Honghong
Date: 2014, 2014-07
Description: Bax is a pro-death tumor suppressor in the Bcl-2 family, and is frequently mutated in microsatellite instable tumors, especially Hereditary...
Show moreBax is a pro-death tumor suppressor in the Bcl-2 family, and is frequently mutated in microsatellite instable tumors, especially Hereditary Non-Polyposis Colorectal Cancer (HNPCC). The loss of apoptotic Bax contributes to tumor development and chemoresistance. We recently uncovered that the combination of a Bax microsatellite mutation with a specific alternative splicing generated a unique Bax isoform (BaxΔ2) in Bax-negative cells. Similar to the prototype Baxα, BaxΔ2 is a potent pro-apoptotic molecule. However, the pro-apoptotic mechanism, therapeutic implication, and tumor tissue distribution of BaxΔ2 protein remain elusive. In this thesis research, we isolated and analyzed isogenic sub-cell lines that represent different Bax microsatellite statuses from colorectal cancer cells. We found that the colon cancer cells harboring Bax microsatellite G7/G7 alleles produced low levels of endogenous BaxΔ2 transcripts and proteins. BaxΔ2-positive cells were selectively sensitive to a subgroup of chemotherapeutics in comparison with BaxΔ2-negative cells. Different from other Bax isoforms, which mostly act through targeting mitochondria, BaxΔ2 recruited caspase-8 into the aggregates for activation, and consequently induced cell death independent of the mitochondrial pathway. Furthermore, the distribution of BaxΔ2 protein was mostly found in well-differentiated epithelial cells in primary colon tumor tissues or in primary squamous buccal cells, which contain Bax G7 mutation. However, not all cells harboring the Bax G7 mutation had a detectable level of BaxΔ2 proteins. These data suggest that, similar to Baxα, BaxΔ2 protein is pro-apoptotic, but not toxic to normal cells; expression of BaxΔ2 protein restores apoptotic program in Bax negative cells via a non-classical signaling pathway. Importantly, BaxΔ2 may provide a selective chemotherapeutic advantage for certain Bax-negative colon tumors.
Ph.D. in Biology, July 2014
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Title: ROLE OF EXTRACELLULAR MATRIX IN CELLULAR BEHAVIOR AND TISSUE FUNCTION
Creator: Sridharan, Indumathi
Date: 2012-04-22, 2012-05
Description: Matrix-dictated control of stem cell differentiation and tissue status are of considerable interest to cell biologists and tissue engineers....
Show moreMatrix-dictated control of stem cell differentiation and tissue status are of considerable interest to cell biologists and tissue engineers. To create suitable biological scaffolds for tissue engineering and cell therapeutics, it is essential to understand the matrix mediated specification of cell lineage. Our study examines the role of matrix properties on cellular behavior and tissue mechanics. To this end, we studied the effect of collagen type I on stem cell differentiation and its mechanical properties within a live tissue. We altered the properties of collagen type 1 by incorporating CNT. The collagen-carbon nanotube (collagen-CNT) composite material was stiffer with thicker fibers and longer D-period. We find that the enhanced mechanical and structural properties of collagen-CNT allow for rapid and efficient derivation of neural progenitors from human decidua parietalis placental stem cells (hdpPSC). Both structure and stiffness of the matrix are important determinants of neural differentiation rate. Strikingly, the collagen-CNT matrix, unlike collagen, imposes the neural fate by an alternate mechanism that is independent of beta-1 integrin and beta-catenin. The study demonstrates the sensitivity of stem cells to subtle changes in the matrix and the utilization of a novel biocomposite material for efficient and directed differentiation of stem cells. Investigation of connective tissue disorders has led to the understanding of the important role played by collagen. So far, native collagen fibers within an intact tissue have not been examined. In this study, we employed a unique approach- histochemical staining guided high-resolution elasticity mapping- to study collagen and smooth muscle in fresh vaginal wall connective tissue. The comparative study of tissues collected from healthy pre-menopausal (pre-M) and post-menopausal (post-M) women suggest that during menopause, collagen’s structure and elasticity are subtly altered. The systematic analysis enables detection of minute changes in collagen in non-fatal conditions such as pelvic organ prolapse and other genitor-urinary disorders, where the initial symptoms are subtle and multivariate and where early diagnosis will allow non-invasive interventions and reduce incidence of surgical correction for these common disorders.
Ph.D. in Molecular Biochemistry and Biophysics, May 2012
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Title: Sustainable New City - Johor, Malaysia
Creator: Meah, Nasser Meah Bin Mahmud
Date: 2011-12-06, 2011-12
Description: The purpose of this thesis is to develop an effective design approach necessary in building a new city. The challenge is to assemble a...
Show moreThe purpose of this thesis is to develop an effective design approach necessary in building a new city. The challenge is to assemble a background observations and research that will provide an understanding of the concepts required for developing new sustainable cities. It is hopeful that the ideas and design process can also be a framework to be applied on other undeveloped land that has the potential for new cities particularly in Malaysia. The main idea is to develop a thorough understanding of how the built environment plays an important role in shaping a community as well as identifying the technology involved. It specifically addresses the central issues involved with the art of place making, which determines the success of any particular urbanity. Environment then becomes the most important factor responsible for the physical, mental, and psychological development of an urban society.
M.S. in Architecture, December 2011
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Title: EFFICIENT AND FAIR RESOURCE ALLOCATION FOR OFDMA NETWORKS
Creator: Alavi, Seyed Mohamad
Date: 2012-11-26, 2012-12
Description: In Orthogonal Frequency Division Multiple Access (OFDMA) systems, resources, including subcarriers, bits and power, need to be adaptively...
Show moreIn Orthogonal Frequency Division Multiple Access (OFDMA) systems, resources, including subcarriers, bits and power, need to be adaptively allocated to users in order to improve spectral efficiency, increase capacity, and reduce power consumption, while satisfying the Quality of Service (QoS) requirements for users. Most of the previous works concentrate on satisfying rate and power requirements, however providing delay requirement is also necessary, especially with increasing demand on delay-sensitive applications. We first model the resource allocation problem as a cross-layer optimization problem considering the constraints on bit error rate (BER), data rate, total power, as well as delay. We first develop a nonlinear optimization model, which generally requires high computation complexity. To consider a more realistic scenario, we take into account imperfect Channel State Information (CSI) due to estimation errors or channel feedback delay, and incorporate the imperfect CSI into the optimization problem formulation. We then derive the solution through a dual decomposition method. Due to the duality gap between the original and dual optimizations, we convert the non-linear optimization to an equivalent linear formulation so that an exact solution can be obtained. To further reduce the complexity, we develop a heuristic algorithm to provide a solution close to the optimum. Then, we study the notion of fairness in the context of resource allocation. In particular, cooperative game theory can be applied to OFDMA networks for fair resource allocation. We apply two cooperative games, Non-Transferable Utility (NTU) game and Transferable Utility (TU) game, to provide fairness in OFDMA networks. In NTU game, fairness is achieved by defining appropriate objective function, while in TU game, fairness is provided by forming the appropriate network structure. For NTU game, we analyze the Nash Bargaining Solution (NBS) as a solution of NTU game taking into account CSI and Queue State Information (QSI). In a TU game, we show that coalition among subcarriers to jointly provide rate requirements leads to better performance in terms of power consumpviii tion. We show that although NTU and TU games are modeled as rate adaptive and margin adaptive problems, respectively, but both solutions provide a fair distribution of resources with minimum fairness index of 0.8. Although NBS can provide fairness, the fairness is not from user perspective. In competitive fairness, which is based on auction theory, each user is responsible for his/her own action. A distributed allocation of resources in OFDMA networks is studied through auction theory. A combinatorial auction is formulated in which the users’ utility enforce the truthful resource demands. Since the original problem is NP hard, a method based on simulated annealing applied to find near-optimum results. Then, we turn our attention toward a more complicated scenario of multicell OFDMA networks. A combinatorial auction, which takes into account the interference from adjacent cells is presented. Auction objective is to minimize the interference, while power of users is limited. Due to the complexity of original problem, we apply a heuristic approach, in which the bids are ordered based on the linear programming approximation of combinatorial auction, and then local improvements are made in the order of bids. Our iterative approach along with the proposed load control scheme provides fair distribution of resources to the users, regardless of their position in the cell. Finally, we propose a comprehensive auction in OFDMA network. We present an auction framework for allocation of subcarriers, in which winner pays monitoring and entry fees, in addition to the price which he is paying for the allocated subcarrier. We prove that in our framework users will avoid bidding for the subcarriers where they have a relatively low chance of winning. We obtain optimal bidding strategy based on Bayesian Nash Equilibrium (BNE) in which users are maximizing their net profit. In a Fractional Frequency Reuse (FFR) implementation of frequency planning, we will find a focal distance which classifies the users into cell-center and cell-edge users. It is shown that the focal distance increases as the interference decreases.
PH.D in Electrical Engineering, December 2012
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Title: ULTRASONIC RANGING AND INFRARED DEPTH PROFILING FOR 3D IMAGE RECOl'STRUCTION AND SCENE ANALYSIS
Creator: Jia, Weldi
Date: 2013, 2013-07
Description: This doctoral work cannot be done without the help, support and dedication of numerous people. First of all, I will give my great thanks to my...
Show moreThis doctoral work cannot be done without the help, support and dedication of numerous people. First of all, I will give my great thanks to my advisor Dr. Jafar Saniie, who is patient, fundamental and knowledgeable in providing advices, suggestions and guidance to all my six years' study. I would like to express my sincere thanks for his encouragement and nancial support during my study. I will never forget the days and nights he spent with me doing research work in the ECASP research lab. His spirit of carefully searching, friendly talking and knowledgeably thinking stays in my mind forever. My gratitude extends to my committee members, Dr. Anjali, Dr. Moderes and Dr. Oruklu. Also, I would like to give my thanks to my colleagues and friends, especially the people in ECASP research lab, Won-Jae, Sufeng, Thomas, Spenser and Pramod. Their kindness and powerful knowledge in di erent elds help me enhance my work so much. I will never forget the days debugging programs with them and the days we cheered for our success. I would like to dedicate this thesis to my family, especially to my grandfather who just passed away but gave me nancial support and advices from childhood till now, my father who is not able to speak after an accident during my study, my mother who is taking care of my father herself during the past six years, and my wife Wenhui Liu, who encouraged and helped me living in the United States. I promise that I will use what I learned from here to change the world and their constant support of my academic ventures from the beginning to the present would be valuable. Thank you Grandpa, rest in peace in heaven.
PH.D in Electrical Engineering, July 2013
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Title: LARGE-SCALE SIMULATION OF ELECTRIC POWER SYSTEMS FOR WIND
Creator: Wei, Tian
Date: 2011-08, 2011-07
Description: The utilization of wind energy will pose great socioeconomic benefits with reductions in power plant emissions and the supply of zero cost...
Show moreThe utilization of wind energy will pose great socioeconomic benefits with reductions in power plant emissions and the supply of zero cost energy; however, largescale wind energy integration could introduce inevitable challenges to regional transmission systems and hourly system operations. This thesis addresses the congestion identification, simulation and analysis of large-scale electric power systems in different scenarios, large-scale wind energy integration and related transmission expansion issues. A methodology based on the security-constrained unit commitment (SCUC) is applied to analyze the transmission congestions in the Eastern Interconnection of the United States. The identified congestions are visualized along with the Geographical Information System (GIS) data and compared with the results in National Electric Transmission Congestion Study (NETCS) published by the Department of Energy of the United States in 2006. The study also provides the locational marginal price (LMP) information in the Eastern Interconnection, which is not available in the NETCS report. This thesis implements a comprehensive simulation and scenario analysis of the Illinois electric power system for the year 2011. Possible scenarios representing electrical load sensitivities to economic growth, fuel price variations, and the impact of carbon cost, are studied. This thesis presents the hourly simulation results for the large-scale wind energy integration in the Eastern Interconnection of the United States. An hourly unit commitment is applied for the simulation of the economics of wind energy integration in the year 2030. The energy portfolio for supplying the hourly load in 2030 is developed based on wind integration levels. The sensitivities of fuel price, wind energy quantity, xvii load forecast, carbon cost, and load management to the proposed 2030 wind integration are studied. This thesis identifies transmission congestions and expands the existing transmission system in the Eastern Interconnection of the United States for accommodating a large-scale integration of wind energy. Violated transmission flows which would cause the infeasibility of hourly SCUC are identified. An iterative transmission expansion analysis is implemented to identify the minimum required additions to the Eastern Interconnection for mitigating hourly transmission congestions.
Ph.D. in Electrical Engineering, July 2011
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Title: POLARIZATION INDUCED BY A TERAHERTZ ELECTRIC FIELD ON A CONDUCTIVE PARTICLE
Creator: Shen, Tao
Date: 2013, 2013-05
Description: Interactions of an electromagnetic wave with an object of dimensions small compared to the wavelength can often be accounted for by...
Show moreInteractions of an electromagnetic wave with an object of dimensions small compared to the wavelength can often be accounted for by considering the dipole moments, which are effective in explaining the scattering characteristics in the frequency range referred to as the Rayleigh region. Dielectric functions derived from polarization processes due to molecular orientation or bound charge displacements have been employed over the years to account for the scattering properties of particles. In the presence of mobile charges, bulk conductivity may be incorporated with a complex dielectric function to explain the peak in absorption near the plasma frequency exhibited by metallic particles in the optical region. With the current interest in nanostructures, an investigation of the electromagnetic properties of a conductive particle with attention given to space-charge effects would appear timely. This can be accomplished by coupling the transport equations of the charge carriers to the Maxwell’s equations. Results of computations performed for elementary structures such as plates and particles revealed the screening of the internal field while dispersion and absorptions effects are shown by the complex dipole moments. To gain insight into the nature of charge-wave interactions, results based on quasi-static formulation for the electric field will be compared with those based on full-wave analysis, with special attention given to the charge and current distributions within the structure. By consideration of the physical process of charge carrier motion and lattice polarization, the equivalent circuit model for a conductive nanoparticle in the terahertz frequency range is developed. All circuit elements are of electrical nature and can be directly expressed in terms of material parameters. The equivalent circuit can serve as the basis of analysis for composite structures and aggregates of which the conductive nanoparticle is a constituent.
PH.D in Electrical Engineering, May 2013
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Title: MODEL-BASED EXPLORATION OF THE FEASIBILITY OF CREATING MULTIPLE PROPERTY GRADIENT IN CROSSLINKED POLYMER FILMS IN CONTROLLED LIVING POLYMERIZATION
Creator: Qin, Zikai
Date: 2014, 2014-05
Description: The functional gradient materials have been widely used in chemical engineering, biomedical engineering and tissue engineering since they have...
Show moreThe functional gradient materials have been widely used in chemical engineering, biomedical engineering and tissue engineering since they have been reported because of their admirable mechanical, physical and chemical properties. Several traditional methods of synthesis gradient materials are known to all. Here we introduced a new mathematical model of designing and producing crosslinked polymeric films with target multiple gradients. We derive our model from batch reactor system and explore how each condition of the system affects the gradient of the polymer film. Then we extend to semi-batch reactor to control the gradient in crosslink density and set up different strategies to make the target multiple gradient crosslink density accomplish. With any given target gradient crosslinked polymer film, we can make an exact similar film in our model.
M.S. in Chemical Engineering, May 2014
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Title: PARADIGM SHIFT IN REMOTE EDUCATION FOR THE LABORATORY: A SOCIAL APPROACH TO DISTANCE LEARNING
Creator: Hanley, Richard
Date: 2011-12, 2011-12
Description: With modern telecommunication tools the ability for two individuals to work together remotely has greatly improved. Moreover, there have been...
Show moreWith modern telecommunication tools the ability for two individuals to work together remotely has greatly improved. Moreover, there have been great strides made to improve handling medium to large groups of people in real time in remote settings, viz. the teleconference and webinar. However, the status of remote tools for laboratory environments where there is significant hardware and the individuals are more likely to talk amongst themselves in irregular patterns is not nearly as well studied. This thesis examines the way most laboratories in electrical engineering are setup, and creates a model for how to create a remote environment for distance learning. It then discusses the current state of the art, and how such an implementation of the model can be made with such tools. Finally a usability study of the implementation is examined. The primary result of the usability study is that when moving to a remote environment the social paradigm that students and instructors use is likely to change, and simply working on creating a virtual mirror to the laboratory may not work in the future.
M.S. in Electrical Engineering, December 2011
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Title: IMPROVED DYNAMIC CONTRAST ENHANCED MR IMAGING WITH AN APPLICATION TO PROSTATE CANCER LOCALIZATION
Creator: Afshar, Niloufar Totonchi
Date: 2011-07, 2011-07
Description: Prostate cancer is one of the most frequently detected cancers and a leading cause of death for men in the United States. Fortunately, chances...
Show moreProstate cancer is one of the most frequently detected cancers and a leading cause of death for men in the United States. Fortunately, chances of successful treatment significantly improve when prostate cancer is diagnosed at an early stage. An accurate and reliable imaging technique that can localize tumors is very valuable for example in guiding needle biopsy, therapy, as well as surgery. Current imaging techniques such as ultrasound provide unsatisfactory result for tumor localization. Therefore, Multispectral Magnetic Resonance Imaging (MRI) emerged as an alternative method of imaging for prostate cancer. An important part of multispectral MRI is Dynamic contrast enhanced MRI (DCE-MRI). Traditionally, a compartmental model is used with DCE-MRI to estimate parametric images. However these images are usually very noisy. Therefore, we propose to use directly the series of DCE-MRI for tumor localization instead of the pharmacokinetic parameters which are derived from DCE MR images through a compartmental model. As a second contribution, we have developed new features in addition to traditional parameters based on different characteristic of tumor and normal pixels. These new features are standard deviation and the energy of the first half of the spectrum divided by the energy of the second half of the spectrum based on an analysis of TACs for tumor and normal pixels. We use quantitative and qualitative evaluation methods to demonstrate that employing DCE-MRI directly as features and our proposed features result in an improvement in terms of tumor localization performance.
M.S. in Electrical Engineering, July 2011
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Title: THE EFFECT OF FLOW ON MICROPARTICLE TRANSPORT AND THE ROLE OF MICROPARTICLES IN THROMBOSIS
Creator: Lee, Ying-hui
Date: 2012-11-27, 2012-12
Description: Elevated monocyte/macrophage-derived microparticles (MPs) have been found to correlate with thrombotic complications. These MPs carry tissue...
Show moreElevated monocyte/macrophage-derived microparticles (MPs) have been found to correlate with thrombotic complications. These MPs carry tissue factor (TF), the principal coagulation pathway initiator, as their parental cells and expose anionic phospholipid phosphatidylserine (PS), which can promote thrombin generation and fibrin formation. During thrombus development, MPs may be delivered to the injured/dysfunctional vascular endothelium or biomaterial surfaces and influence the process of thrombosis. MPs are submicron membrane vesicles that may have increased transport and/or binding capabilities compared to platelets or other cell types due to their decreased size and their higher Brownian diffusion. MPs and their surface molecules can be delivered to surfaces, either biological or prosthetic, and alter the local environment. Little is known of the mechanisms by which MPs are transported to and impart their biological activity on surfaces, especially in blood. Such a transfer of activity will depend on the ability of MPs to be transported to the surface, the strength of adhesion of the MPs on the surface and the nature of the activity/host interaction. In the present study, physical and biological properties of MPs generated from macrophage-like cell lines by endotoxin stimulation were characterized, the transport of MPs to surface by flow was investigated, and the import biological activity on surfaces was elucidated. We observed that the deposition of MPs suspended in buffer on glass surfaces was strongly shear-dependent using a well-defined parallel plate flow chamber. The diffusivity coefficients of MPs at shear rate ranges ranging from 100 to 3200 s-1 were determined from the classical mass transport equation proposed by Leveque and the values were found to be of the same order of magnitude as predicted by Brownian xi diffusion. MPs non-specific attachment to glass was dominated by electrostatic interactions; this was verified by changing the surrounding ionic strength of the suspending solution. In addition to shear rate, red blood cells (RBCs) also influenced MP adhesion due to the complex movement of RBCs. Such movement has been shown to enhance the adhesion of platelets (1-2 micron size cells) to surfaces in flowing blood. MP lateral transport was enhanced at low concentrations of RBCs and reduced at higher concentration of RBCs. The reduction of MP deposition was due to the competition for surface binding sites between the two populations of MPs. The two types of MPs studied here, those produced by macrophages after endotoxin stimulation and those produced by RBCs during experimental preparation (repeated centrifugal washing) have the capability of nonspecific binding to artificial surfaces in a competitive manner. Finally, we demonstrated that the amount of adherent MPs on surfaces influenced fibrin formation via both a TF-dependent and a negatively charged phospholipid pathway. These findings suggest that procoagulant MPs may modulate thrombotic events under certain conditions, especially in MP-associated diseases. The knowledge of the effects of flow on MP transport and the influence of increased MPs on thrombosis may provide novel insights for the transfer of biological activity to relatively passive surfaces.
PH.D in in Biomedical Engineering, December 2012
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Title: Framework For Cloud-Based BIM Governance
Creator: Mehraj, Isma
Date: 2020
Description: Due to the rapid adoption of building information modeling (BIM) in the architecture, engineering, and construction (AEC) every building can...
Show moreDue to the rapid adoption of building information modeling (BIM) in the architecture, engineering, and construction (AEC) every building can be visualized and interpreted even before its foundation touches the ground. BIM methods are expanding and have entered mainstream use that requires immediate consideration. BIM is new and difficult to operate as mostly due to the enormous amount of data that causes improper data management. The objective of this study is to formulate a cloud-based BIM governance framework with a focus on practical issues for its implementation in the construction organizations. A framework was developed to study Data Management, Team Collaboration, Data Organization, and Legal Assurance as major constructs. It is expected that the constructs will provide a benchmark for BIM cloud governance implementation for BIM /VDC engineers to follow. The incorporation of this framework in BIM practices would produce new opportunities for the AEC community to work in collaboration and increase efficiency in data sharing. A survey among a wide spectrum of BIM/VDC practitioners from major construction organizations in the United States was conducted to explore and find evidence of the strength of the constructs. We anticipate that this framework will provide a basis for assessment and recognition of pivoting, driving factors for practical and effective BIM implementation.
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Title: A Risk-Based Approach in Selecting Design Natural Hazard Loads for Temporary Structures
Creator: Saleh, Eman
Date: 2020
Description: Temporary structures are systems that are used for short period applications such as in maintenance and retrofit applications or for staged...
Show moreTemporary structures are systems that are used for short period applications such as in maintenance and retrofit applications or for staged performances. Examples of its applications are tents, scaffoldings, and other facilities that have a short service life. Structures under construction and structures under serviceability conditions also fall under this category of structures; because their service time period is only limited to the duration of the construction, which is much shorter than the lifetime of the finished structure. One of the main characteristics of these types of structures is their high vulnerability to stability. Most specifications rarely cover temporary structures. Designing these structures to appropriate levels of the dead and live load does not impose an issue, in which using the same load factors as in permanent structures is considered a reasonable choice. However, an issue is raised when choosing the appropriate wind, seismic and snow load levels, where using the same exposure levels as in permanent structures may not be a desirable economic decision. Thus, for temporary structures, it makes sense to reduce the extreme event design loads proportional to the intended design life. In this manner, it is imperative to have specific rules or guidelines that would address the design aspects and reliability of these structures especially against lateral loads such as wind and earthquakes. This study aims at establishing several decision-making processes that could help contractors, designers, and erectors of temporary works to decide upon safety factors and/or return periods for environmental loads, with emphasis on the wind load. This decision-making process can be used in temporary projects (e.g., bridge erecting) to establish a design criterion based on the nature of the project. The study shows that the optimal decision-making process depends on the willingness to take advantage of wind locality characteristics (e.g., seasonality factor) in certain construction period or region, type of information available for the decision-maker (i.e., precise or imprecise), the risk associated with the constructed facility or the temporary structure itself, a potential for recourse actions, and the decision-maker’s attitude toward the trade-off between losses and gains with respect to uncertainty. The suggested decision-making process proposed is Bayesian decision process, the fuzzy decision process; (3) a two-stage stochastic programming solution; and (4) case-based decision theory. Several practical examples are presented in this thesis to show how different situations may require varying decision-making processes in order to reach the optimal decision. The design of temporary structures can be altered in response to a forecasted hurricane; thus, we propose a three-stage stochastic programming solution to decide upon their optimal wind design load. In addition, we extend the hurricane catastrophe models for application in temporary structures. This enables contractors to forecast the hurricane losses as a basis for estimating the adequate catastrophe cover such as insurance premiums and reinsurance for temporary structures. This scheme is then illustrated in an example for deciding the required temporary bracings for a steel frame under construction during the hurricane season.To prevent temporary structures from collapse, it is important to investigate the performance quality of previous projects and remove any causes for potential mishaps. This can be done by continuous monitoring of different projects and an investigation of accidents, if any, to help prevent future failures. In this study, we use an audit evidence scheme based on commonly available evidence theories used in the construction industry. In one such theory, the evidence is represented via a tree structure, in which the propagation is toward the variables that represent the project as a whole and separate work packages within a project. For simplicity, we only consider the binary case of variables i.e. whether or not a project conforms to the quality standards. The formulation of the auditing tool relates belief functions to the assertion of the quality assurance and quality control (QA/QC) measures and provides formulas for human error risk. These formulas provide plausibilities of human error in a belief-function format. An auditor may use the belief values to assess the degree of quality performance and to identify the sources of the problem in temporary work. We further illustrate the method in a practical application to evaluate the shoring/reshoring operations for estimating the construction risk in a multistory concrete structure. This evaluation may be used to decide on an appropriate time for formwork removal, shoring/reshoring schedule, casting cycles, post-tensioning sequence, and the required number of reshoring levels given the available evidence. To reduce the computational burden, we describe the shoring/reshoring system as a multi-state system (MSS) where the universal generating function (UGF) was used to estimate the reliability of the system.
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