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Title: COMPUTATION AND ANALYSIS OF TUMOR GROWTH
Creator: Turian, Emma
Date: 2016, 2016-05
Description: The ability of tumors to metastasize is preceded by morphological instabilities such as chains or fingers that invade the host environment....
Show moreThe ability of tumors to metastasize is preceded by morphological instabilities such as chains or fingers that invade the host environment. Parameters that control tumor morphology may also contribute to its invasive ability. In this thesis, we investigate tumor growth using a two-phase Stokes model. We first examine the morphological changes using the surface energy of the tumor-host interface and investigate its nonlinear dynamics using a boundary integral method. In an effort to understand the interface stiffness, we then model the tumor-host interface as an elastic membrane governed by the Helfrich bending energy. Using an energy variation approach, we derive a modified Young-Laplace condition for the stress jump across the interface, and perform a linear stability analysis to evaluate the effects of viscosity, bending rigidity, and apoptosis on tumor morphology. Results show that increased bending rigidity versus mitosis rate contributes to a more stable growth. On the other hand, increased tumor viscosity or apoptosis may lead to an invasive fingering morphology. Comparison with experimental data on glioblastoma spheroids shows good agreement especially for tumors with high adhesion and low proliferation. Next, we evaluate tumor regression during cancer therapy by a combined modality involving chemotherapy and radiotherapy. The goal is to address the complexities of a vascular tumor (e.g. apoptosis and vascularization) during treatment. We introduce an apoptotic time delay and study its impact on tumor regression using numerical and asymptotic techniques. In particular, we implement the linear-quadratic model and identify two extreme sets of parameter data, namely the slow, and fast tumor response to therapy. Numerical simulations for the slow response set show good agreements with data representing non-small cell lung carcinoma. Using the evolution equation for tumor radius with time delay, we find that tumors with shorter time interval to the onset of apoptosis shrink faster.
Ph.D. in Applied Mathematics, May 2016
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Title: Monitoring of multivariable dynamic processes and sensor auditing
Creator: Negiz, A., Cinar, A.
Date: 1998-10
Publisher: ELSEVIER SCI LTD
Description: Industrial continuous processes are usually operated under closed-loop control, yielding process measurements that are autocorrelated, cross...
Show moreIndustrial continuous processes are usually operated under closed-loop control, yielding process measurements that are autocorrelated, cross correlated, and collinear. A statistical process monitoring (SPM) method based on state variables is introduced to monitor such processes. The statistical model that describes the in-control variability is based on a canonical variate (CV) state space model. The CV state variables are linear combinations of the past process measurements which explain the variability of the future measurements the most, and they are regarded as the principal dynamic dimensions. A T-2 statistic based on the CV state variables is utilized for developing the SPM procedure. The CV state variables are also used for monitoring sensor reliability. An experimental application to a high temperature short time (HTST) pasteurization process illustrates the proposed methodology.
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Title: Large Scale Integration of Sustainable Energy and Congestion Management in Western Interconnection
Creator: Aflaki Khosrosha, Kaveh
Date: 2012-07-12, 2012-07
Description: Large scale sustainable energy like wind and solar energy integration to the bulk grid could introduce inevitable challenges to regional...
Show moreLarge scale sustainable energy like wind and solar energy integration to the bulk grid could introduce inevitable challenges to regional transmission and generation systems. The most important challenges for transmission system are the congestion management and planning for transmission expansion to transfer the zero cost generated electricity. Another big challenge is competition of current fuel based generation units in the electricity market with zero cost sustainable energy. In this dissertation all these challenges identified and analyzed for large scale grid. This thesis brings a new method used to study transmission congestions in Western Interconnection of the United States. The process involved Security-Constrained Unit Commitment (SCUC) formulation applying its results for analysis of transmission congestion. This thesis also presents results and findings in simulation of the system operation in the Western Interconnection of the United States with the inclusion of large scale wind and solar energy integration for year 2030. High level of wind and solar energy with the forecasted wind and solar time series profiles were integrated to the Western Interconnection grid. Their impact on different existing types of generation plants is studied. The sensitivity of the fuel prices, wind turbine power output, load volatility and demand side management as well as carbon tax are analyzed in different possible scenarios. In order to incorporate large scale of sustainable energy into a bulk electricity grid footprint, planned transmission expansion showed need to take place. Transmission expansion reduces grid congestion and balances Locational Marginal Prices (LMP). This thesis explores the advancements in high-performance computing and visual analytics of economic-based transmission expansion in the Western Electricity Coordinating Council (WECC). This expansion is based on 2018 and 2029 forecasted data. It identifies transmission congestions and average of LMP for each area, and expands the transmission system while accommodating large scale wind and solar energy to achieve the Department of Energy’s renewable energy vision for year 2030. An iterative transmission expansion analysis, based on the average LMP for each area, is used to identify the minimum WECC transmission lines required. All results are visualized on the Geographical Information System (GIS) format map of North America.
Ph.D. in Electrical Engineering, July 2012
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Title: AXISYMMETRICAL JET FORCED BY FUNDAMENTAL AND SUBHARMONIC TONES
Creator: Raman, G, Rice, Ej
Date: 1991-07
Publisher: AMER INST AERONAUT ASTRONAUT
Description: A circular jet was excited simultaneously by two harmonically related tones. The results of this excitation on jet behavior are reported for...
Show moreA circular jet was excited simultaneously by two harmonically related tones. The results of this excitation on jet behavior are reported for three pairs of Strouhal numbers [St(D) = f*D/U(j) = 0.2 and 0.4, 0.3 and 0.6, 0.4 and 0.8]. For each case, the initial phase difference between the two tones was varied in steps of 45 deg for one full cycle, and the amplitude of the fundamental and subharmonic tones was varied independently over the range of 0.1-7.0% of the jet exit velocity. Several results of this study agreed with other published findings, such as a critical amplitude or the fundamental being required for subharmonic augmentation and the initial phase difference being critical in determining whether the subharmonic is augmented or suppressed. In addition, the detailed documentation or several aspects of this phenomenon, measured in the same experimental facility in a controlled manner, brought out two important points that had eluded previous researchers. First, at high levels of the fundamental and subharmonic forcing amplitudes, the subharmonic augmentation is independent of the initial phase difference. Second, two-frequency excitation is indeed more effective than single-frequency excitation in jet mixing enhancement. Higher spreading rates seem to go along with higher subharmonic levels.
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Title: A study of the effects produced on Portland cement by the addition of various percentages of hydrated lime
Creator: Knuepfer, Claude Albert, Hook, Leonard Doolittle
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofeffectspr00knue
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 99

Title: CORROSION-RESISTANT ELECTRO-CATALYSTS AND SUPPORTS FOR ELECTROCHEMICAL ENERGY CONVERSION
Creator: Wang, Guanxiong
Date: 2016, 2016-12
Description: Polymer electrolyte fuel cells (PEFCs) convert chemical energy of fuels (eg. Hydrogen) directly to electrical energy with excellent power...
Show morePolymer electrolyte fuel cells (PEFCs) convert chemical energy of fuels (eg. Hydrogen) directly to electrical energy with excellent power density, high efficiency, and zero emissions. Several challenges have delayed the commercialization of fuel cells with one being the high cost and durability of the carbon-supported-platinum-based (Pt/C) electrocatalysts. The lifetime/durability issue is critical as insufficient durability/reliability of the catalysts affects the lifetime and economical viability of these devices. Carbon support corrosion is a major durability issue since the corrosion reaction is thermodynamically favorable but kinetically sluggish under normal operating conditions. The potential transients that occur during start and stop in automotive applications can lead to electrode potential excursions of up to 1.5 V and contribute to carbon corrosion. The best way to mitigate support corrosion in PEFCs is to replace the carbon supports with alternatives having high electronic conductivity, surface area and porosity. This dissertation investigates the following carbon alternatives: (i) tin doped indium oxide (ITO) and (ii) 1:1 mixed oxides of ruthenia and silica (RSO). Microstructure characterization and electrochemical evaluations, including accelerated stress tests (start-up/shut-down and load cycling protocols) were performed to evaluate ORR activity, fuel cell performance, and electrochemical stability under PEFC operating conditions. The ITO support and 40%Pt/ITO catalysts demonstrated exceptional electrochemical stability (and reasonable ORR activity) in rotating disk electrode (RDE) experiments under accelerated potential cycling that mimicked automotive drive cycles. However, Pt/ITO exhibited poor performance and stability during MEA evaluation in a PEFC. X-ray photoelectron spectroscopy (XPS) was employed to reveal the degradation modes of Pt/ITO during PEFC operation and it was found that the increase in the surface hydroxide concentration generates a passivating In(OH)3 layer that increases electrode resistance and undermines PEFC performance. The influence of the catalyst support on PEM degradation during PEFC operation was also studied. Rotating ring-disk electrode (RRDE) experiments were employed to estimate the fraction of H2O2 generated during the ORR on the supports (C and RSO) and catalysts (benchmark Pt/C and Pt/RSO). The percentage of H2O2 generated on C and Pt/C was 50% higher than that on RSO and Pt/RSO thus explaining the observed oxidative degradation resistance of the PEM with the latter supports/catalysts.
Ph.D. in Chemical Engineering, December 2016
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Title: A modular simulation package for fed-batch fermentation: penicillin production
Creator: Birol, G., Undey, C., Cinar, A.
Date: 2002-11-15
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Description: Simulation software based on a detailed unstructured model for penicillin production in a fed-batch fermentor has been developed. The model...
Show moreSimulation software based on a detailed unstructured model for penicillin production in a fed-batch fermentor has been developed. The model extends the mechanistic model of Bajpai and Reuss by adding input variables such as pH, temperature, aeration rate, agitation power, and feed flow rate of substrate and introducing the CO2 evolution term. The simulation package was then used for monitoring and fault diagnosis of a typical penicillin fermentation process. The simulator developed may be used for both research and educational purposes and is available at the web site: http://www.chee.iit.edu/ similar to control/software.html.
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Title: AUTOMATIC SUMMARIZATION OF CLINICAL ABSTRACTS FOR EVIDENCE-BASED MEDICINE
Creator: Summerscales, Rodney L.
Date: 2013, 2013-12
Description: The practice of evidence-based medicine (EBM) encourages health professionals to make informed treatment decisions based on a careful analysis...
Show moreThe practice of evidence-based medicine (EBM) encourages health professionals to make informed treatment decisions based on a careful analysis of current research. However, after caring for their patients, medical practitioners have little time to spend reading even a small fraction of the rapidly growing body of medical research literature. As a result, physicians must often rely on potentially outdated knowledge acquired in medical school. Systematic reviews of the literature exist for speci c clinical questions, but these must be manually created and updated as new research is published. Abstracts from well-written clinical research papers contain key information regarding the design and results of clinical trials. Unfortunately, the free text nature of abstracts makes it di cult for computer systems to use and time consuming for humans to read. I present a software system that reads abstracts from randomized controlled trials, extracts key clinical entities, computes the e ectiveness of the proposed interventions and compiles this information into machine readable and human readable summaries. This system uses machine learning and natural language processing techniques to extract the key clinical information describing the trial and its results. It extracts the names and sizes of treatment groups, population demographics, outcome measured in the trial and outcome results for each treatment group. Using the extracted outcome measurements, the system calculates key summary measures used by physicians when evaluating the e ectiveness of treatments. It computes absolute risk reduction (ARR) and number needed to treat (NNT) values complete with con dence intervals. The extracted information and computed statistics are automatically compiled into XML and HTML summaries that describe the details and results of the trial. xiii Extracting the necessary information needed to calculate these measures is not trivial. While there have been various approaches to generating summaries of medical research, this work has mostly focused on extracting trial characteristics (e.g. population demographics, intervention/outcome information). No one has attempted to extract all of the information needed, nor has anyone attempted to solve many of the tasks needed to reliably calculate the summary statistics.
PH.D in Computer Science, December 2013
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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: OIL RECOVERY IN SINGLE CAPILLARIES AND POROUS MEDIA USING WETTING NANOFLUIDS
Creator: Zhang, Hua
Date: 2016, 2016-05
Description: Recent experiments and modeling conducted in our laboratory have demonstrated that the spreading of nanofluids, liquid suspensions of...
Show moreRecent experiments and modeling conducted in our laboratory have demonstrated that the spreading of nanofluids, liquid suspensions of nanosized particles, on solids are enhanced due to self-structuring of nanoparticles in the confined three-phase oil-nanofluid-solid contact region. Nanofluids have recently been proposed as agents for enhanced oil recovery (EOR). Despite recently widely conducted research using nanofluids for EOR, the underlying operating mechanism is not well understood. In this thesis, we attempt to understand the mechanism of nanofluid based EOR and evaluate its performance from reservoir core samples and model systems (glass capillary and sintered bead-pack). To visualize how oil displacement in the rock pores by nanofluid, we conducted model study using hexadecane and single glass capillary and showed the oil film dynamics in air and nanofluid after oil was displaced in the capillary. Based on the understanding of the role of nanofluid on oil displacement in capillaries, we conducted imbibition tests using Berea sandstones and flooding experiments in sintered glass-beads. X-ray microtomography was used to visualize and analyze fluid distribution and to see the effect of nanofluid in EOR. We finally considered fractured media by fabricating such structures. The dynamics of a cylindrical hexadecane layer deposited inside glass capillaries after the oil/air displacement was studied experimentally and by modeling. The oil layer subject to surface perturbation becomes unstable forming uniform, regularly-spaced double concave menisci across the capillary that are bridged with dimples (collars). In order to reveal the phenomena of the film thinning and stability between the double concave meniscus and the dimple, we monitored an air bubble approaching a flat glass surface in hexadecane. We found that the oil film thinning in a cylindrical glass capillary and on a flat glass substrate were similar; We adapted the model proposed by Gauglitz and Radke for our system (oil-air displacement) and solved it numerically. The numerical result shows a stable film between the liquid bridge and the dimple, which is consistent with our experimental observations. We also estimated the meniscus-film-dimple thickness profile and found it was in fair agreement with the model prediction. The dynamics of cylindrical hexadecane film after displacement by a nanofluid in a glass capillary was studied. We found the thick hexadecane film is unstable, and over time it breaks and forms a thin film. Once the thick film ruptures, it retracts and forms an annular rim (liquid ridge) that collects liquid. As the volume of the annular rim increases over time, it forms a double concave meniscus across the capillary and dewetting stops. The thin film on the right side of the double concave meniscus then breaks and the contact angle increases. The process repeats until droplets build along the capillary wall. Finally, the droplets are displaced from the capillary wall by the nanofluid and spherical droplets appear inside the capillary. This is a novel phenomenon not observed during dewetting by a solution without nanoparticles. The theoretical model based on the lubrication approximation using the capillary pressure gradient was developed to estimate the annular rim dewetting velocity. The predicted dewetting velocity is found to be in fair agreement with the experimental value. We conducted imbibition tests using a reservoir crude oil and a reservoir brine solution with a high salinity and a suitable nanofluid that displaces crude oil from Berea sandstone and single glass capillaries. We present visual evidence of the underlying mechanism based on the structural disjoining pressure for the crude oil displacement using a polymeric nanofluid (our definition of such a fluid means a suspension of polymeric particles in an aqueous substrate) in high salinity brine. The polymeric nanofluid is specially formulated to survive in a high salinity environment and is found to result in an increased efficiency of 50% for Berea sandstone compared to 17% using the brine alone at a reservoir temperature of 55 oC. These results aid our understanding of the role of the nanofluid in displacing crude oil from the rock especially in a high salinity environment containing Ca++ and Mg++ ions. Results are also reported using Berea sandstone and a nanofluid containing silica nanoparticles. We conducted a series of flooding experiments at different capillary numbers to quantify the performance of a polymeric nanofluid compared to brine using the sintered glass-beads. A high resolution X-ray microtomography (microCT) was used to visualize oil and brine distribution in a sintered bead-pack before and after nanofluid flooding. The results of flooding experiments showed that an additional oil recovery of approximately 15% is possible with nanofluids compared to brine at low capillary numbers, and is as effective as high capillary number brine flooding. Nanofluid induced additional oil recovery decreases as we increase the capillary number and the total oil recovered shows a marginal decrease. At first glance, these results are opposite of what one expects in the conventional EOR, where oil recovery is known to increase progressively with increasing capillary number. These results cannot be explained based on mobilization theories due to the reduced capillarity. Our results however are consistent with the mechanism of wettability alteration caused by structural disjoining pressure leading to the formation of the wetting nanofluid film between oil and substrate.We presented experimental studies of nanofluid flooding in fractured porous media formed with sintered glass-beads. The nanofluid injection is conducted at a rate where structural disjoining pressure driven recovery is operational. We found an additional 23.8% oil can be displaced using nanofluid after brine injection with an overall displacement efficiency of 90.4% provided the matrix was in its native wettability state. In summary, nanofluids are excellent EOR agents and their economic viability needs to be examined.
Ph.D. in Chemical Engineering, May 2016
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Title: WIDESPAN: 2030-board 1
Creator: Ninan, Janice
Date: 2011-05, 2010-12
Description: Widespan design.Investigating the integration of windmills into longspan structure and investigating the axial forces of tension to span...
Show moreWidespan design.Investigating the integration of windmills into longspan structure and investigating the axial forces of tension to span grater spans using virtual depth concepts with slender lightweight design.
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Title: Incubator for Small Business Manufacturing
Creator: Victor, Jimeniz
Date: 2010-07-29

Title: The thermal conductivity of various forms of tile and their value as fireproofing materials
Creator: Anderson, S. W., Chamberlin, J. F.
Date: 2009, 1915
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/thermalconductiv00ande
Thesis (B.S.)--Armour Institute of Technology

Title: COVERAGE AND CONNECTIVITY IN WIRELESS NETWORKS
Creator: Xu, Xiaohua
Date: 2012-04-25, 2012-05
Description: The limited energy resources, instability, and lacking central control in wireless networks motivates the study of connected dominating set ...
Show moreThe limited energy resources, instability, and lacking central control in wireless networks motivates the study of connected dominating set (CDS) which serves as rout- ing backbone to support service discovery, and area monitoring and also broadcasting. The construction of CDS involves both coverage and connectivity. We ¯rst study sev- eral problems related to coverage. Given are a set of nodes and targets in a plane, the problem Minimum Wireless Cover (MWC) seeks the fewest nodes to cover the targets. If all nodes are associated with some positive prices, the problem Cheapest Wireless Cover (CWC) seeks a cheapest set of nodes to cover the targets. If all nodes have bounded lives, the problem Max-Life Wireless Cover (MLWC) seeks wireless coverage schedule of maximum life subject to the life constraints of individ- ual nodes. We present a polynomial time approximation scheme (PTAS) for MWC, and two randomized approximation algorithms for CWC and MLWC respectively. Given a node-weighted graph, the problem Minimum-Weighted Dominating Set (MWDS) is to ¯nd a minimum-weighted vertex subset such that, for any vertex, it is contained in this subset or it has a neighbor contained in this set. We will propose a (4+²)-approximation algorithm for MWDS in unit disk graphs. Meanwhile, for the connecting part, given a node-weighted connected graph and a subset of terminals, the problem Node-Weighted Steiner Tree (NWST) seeks a lightest tree connecting a given set of terminals in a node-weighted graph. We present three approximation algorithms for NWST restricted to UDGs. This dissertation also explores the applications of CDS, and develops e±cient algorithms for the applications such as real-time aggregation scheduling in wireless networks. Given a set of periodic aggregation queries, each query has its own period , and the subset of source nodes Si containing the data, we ¯rst propose a family of e±cient and e®ective real-time scheduling protocols that can answer every job of each query task within a relative delay under resource constraints by addressing the following tightly coupled tasks: routing, transmission plan constructions, node activity scheduling, and packet scheduling. Based on our protocol design, we further propose schedulability test schemes to e±ciently and e®ectively test whether, for a set of queries, each query job can be ¯nished within a ¯nite delay. We also conduct extensive simulations to validate the proposed protocol and evaluate its practical performance. The simulations corroborate our theoretical analysis.
Ph.D. in Computer Science, May 2012
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Title: DOES NUTRITION KNOWLEDGE MODERATE THE ASSOCIATION BETWEEN PERFECTIONISM AND EATING DISORDER SYMPTOMATOLOGY?
Creator: Schwartz, Natalie
Date: 2017, 2017-05
Description: The trait of perfectionism is a psychological factor linked with the development of disordered eating, though the relation is unclear with...
Show moreThe trait of perfectionism is a psychological factor linked with the development of disordered eating, though the relation is unclear with some studies pointing to perfectionism as a predictor of eating disorder symptoms, while other studies have failed to find a statistically significant association. These discrepant findings suggest a need for understanding other factors that could be impacting the association. Research has suggested that individuals with eating disorders perform better than controls on knowledge of sources of nutrients and that while individuals with eating disorders spend more time reading about nutrition, this knowledge tends to be selective and skewed towards the aspects that maintain the eating disorder. The current study aimed to investigate the role of nutrition knowledge as a factor that may significantly influence the association between perfectionism and disordered eating attitudes. College women (N=122) completed several questionnaires related to disordered eating, nutrition knowledge, and perfectionism. The main research questions were: 1) whether perfectionism was related to disordered eating attitudes, 2) whether nutrition knowledge was related to disordered eating attitudes, and 3) whether nutrition knowledge moderated the relation between perfectionism and disordered eating attitudes. Results supported a positive association between perfectionism and disordered eating attitudes, in line with previous research. Despite a non-significant association between nutrition knowledge and disordered eating attitudes, there was found to be trend level significance (p<.07) for one moderation model. Specifically, the model assessing overall body dissatisfaction accounted for 33.34% of the variance, with a significant main effect for the level of perfectionism,suggesting the greater the degree of perfectionism traits, the greater the level of body dissatisfaction. While more research is needed to further develop an understanding of the link between perfectionism and disordered eating, nutrition knowledge is one possible avenue to explore in order to develop more effective prevention and intervention efforts.
M.S. in Psychology, May 2017
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Title: AN INTEGRATED DATA ACCESS SYSTEM FOR BIG COMPUTING
Creator: Yang, Xi
Date: 2016, 2016-07
Description: Big data has entered every corner of the fields of science and engineering and becomes a part of human society. Scientific research and...
Show moreBig data has entered every corner of the fields of science and engineering and becomes a part of human society. Scientific research and commercial practice are increasingly depending on the combined power of high-performance computing (HPC) and high-performance data analytics. Due to its importance, several commercial computing environments have been developed in recent years to support big data applications. MapReduce is a popular mainstream paradigm for large-scale data analytics. MapReduce-based data analytic tools commonly rely on underlying MapReduce file systems (MRFS), such as Hadoop Distributed File System (HDFS), to manage massive amounts of data. In the same time, conventional scientific applications usually run on HPC environments, such as Message Passing Interface (MPI), and their data are kept in parallel file systems (PFS), such as Lustre and GPFS, for high-speed computing and data consistency. As scientific applications become data intensive and big data applications become computing hungry, there is a surging interest and need to integrate HPC power and data processing power to support HPC on big data, the so-called big computing. A fundamental issue of big computing is the integration of data management and interoperability between the conventional HPC ecosystem and the newly emerged data processing/analytic ecosystem. However, data sharing between PFS and MRFS is limited currently, due to semantics mismatches, lacking communication middleware, and the diverged design philosophies and goals, etc. Also, challenges also exist in cross-platform task scheduling and parallelism. At the application layer, the data model mismatch between the raw data kept on file systems and the data management software of an application impedes cross-platform data processing as well. To support cross-platform integration, we propose and develop the Integrated Data Access System (IDAS) for big computing. IDAS extends the accessibilities of programming models and integrates the HPC environment with the data processing MapReduce/Hadoop environment. Under IDAS, MPI applications and MapReduce applications can share and exchange data under PFS and MRFS transparently and efficiently. Through this sharing and exchange, MPI and MapReduce applications can collaboratively provide both high-performance computing and data processing power for a given application. IDAS achieves its goal with several steps. First, IDAS enhances MPI-IO so that MPI-based applications can access data stored in HDFS efficiently. Here the term efficient means that HDFS is enhanced to support MPI-based applications. For instance, we have enhanced HDFS to transparently support N-to-1 file write for better write concurrency. Second, IDAS enhances Hadoop framework to enable MapReduce-based applications process data that resides on PFS transparently. Please notice that we have carefully chosen the term “enhance” here. That is MPI-based applications not only can access data stored on HDFS but also can continue access data stored on PFS. The same is for MapReduce-based applications. Through these enhancements, we achieve seamless data sharing. In addition, we have integrated data accessing with several application tools. In particular, we have integrated image plotting, query, and data subsetting within one application, for Earth Science data analysis. Many data centers prefer erasure-coding rather than triplication to achieve data durability, which trades data availability for lower storage cost. To this end, we have also investigated performance optimization of the erasure coded Hadoop system, to enhance Hadoop system in IDAS.
Ph.D. in Computer Science, July 2016
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Title: DYNAMIC COHERENT ACCEPTABILITY INDICES AND THEIR APPLICATIONS IN FINANCE
Creator: Zhang, Zhao
Date: 2011-05-02, 2011-05
Description: This thesis presents a unified framework for studying coherent acceptability indices in a dynamic setup. We study dynamic coherent...
Show moreThis thesis presents a unified framework for studying coherent acceptability indices in a dynamic setup. We study dynamic coherent acceptability indices and dynamic coherent risk measures. In particular, we establish a duality between them. We derive representation theorems for both dynamic coherent acceptability indices and dynamic coherent risk measures in terms of so called dynamically consistent sequence of sets of probability measures. In addition, we present an alternative approach to study dynamic coherent acceptability indices and the representation theorem. Finally, we provide examples and counterexamples of dynamic coherent acceptability indices, and their applications in portfolio management.
Ph.D. in Applied Mathematics, May 2011
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Title: POWER ELECTRONIC INTERFACE FOR AN OFF-GRID SOLAR POWERED ENERGY STORAGE SYSTEM
Creator: Mao, Yanwen
Date: 2012-10-17, 2012-12
Description: There are about 1.5 billion people in the world with no access to electricity. Of these, a significant number of people live in rural parts of...
Show moreThere are about 1.5 billion people in the world with no access to electricity. Of these, a significant number of people live in rural parts of Africa and Asia. It is very inconvenient and unhealthy for them to work or study at night with the poor light from a candle or kerosene lamp. Additionally, since they do not have a continuous or predictable supply of power, it can be significantly difficult for them to use modern electronic devices such as cell phones, computers or sometimes even basic amenities such as lights and fans. For such situations, an energy storage system powered by solar energy can be a good solution, while being environmentally friendly and easy to use. In this thesis, the design and analysis of an off-grid solar powered energy storage system is presented. It consists of a solar panel, battery pack, control circuit, bidirectional DC/DC converter, and inverter. Operation of this system can be described in terms of two modes. In the daytime, the solar panel absorbs energy from sun light; the DC/DC converter boosts the voltage to a certain value and charges the battery pack. During the nighttime, the battery pack provides energy to the circuit; the DC/DC converter boosts voltage level and the inverter inverts DC voltage to single phase AC voltage; this output of 110V AC voltage can charge cell phones, run an energy save lamp, a fan, or even power a laptop. Details of the design process, system operation, components used in the system, simulation and experimental results are explained in the thesis. The main contribution of the thesis is the development of a new off-grid solar powered energy storage system control strategy that can store solar energy in the battery and provide regular 110V AC xii voltage output to the load when needed; additionally, the implementation of the concept along with testing on an experimental set-up is discussed.
M.S. in Electrical Engineering, December 2012
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Title: A NUMERICAL-METHOD FOR DETERMINING OPTIMAL PARAMETER VALUES IN FORCED PERIODIC OPERATION
Creator: Ozgulsen, F., Adomaitis, R. A., Cinar, A.
Date: 1992-02
Publisher: PERGAMON-ELSEVIER SCIENCE LTD
Description: A numerical approach for determining values of forcing parameters which maximize performance of a periodically forced system is described....
Show moreA numerical approach for determining values of forcing parameters which maximize performance of a periodically forced system is described. Periodic solutions of the system equations plus a differential form of the time-average performance measure are computed with a shooting algorithm. A nonlinear programming package is used to solve the optimization problem. The algorithm is applied to ethylene oxidation process, using the model of a continuous stirred-tank reactor (CSTR).
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Title: B-SPLINE BASED ROBUST FORMULATION IN TOPOLOGY OPTIMIZATION
Creator: Gu, Yu
Date: 2014, 2014-12
Description: In this thesis, we extend the B-spline based density representation to robust topology optimization. The B-spline based representation has...
Show moreIn this thesis, we extend the B-spline based density representation to robust topology optimization. The B-spline based representation has been shown to have the ability of preventing checker-boards. With separate analysis and design mesh, the B-spline based filter is also competitive on computation storage compared with usual density filter. However, the current B-spline based representation is not robust where gray transitions exist. The recent proposed robust formulation highlights the manufacturability that simulates under- or over- etching designs compared with intermediate design. The robustness is demonstrated through three test cases. The minimum length control for quadratic B-splines is analytically derived with respect to knot span size and threshold. Our study about the characteristics of rectangular domain of B-spline based representation, shows that the optimized designs are comparable to those by density filter.
M.S. in Mechanical and Aerospace Engineering, December 2014
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