Search results

Title: RELIABILITY AND ENERGY ANALYSIS FOR EXTREME SCALE SYSTEMS
Creator: Yu, Li
Date: 2015, 2015-12
Description: Reliability and energy are two of the top major concerns in the development of today's supercomputers. To build a powerful machine while at...
Show moreReliability and energy are two of the top major concerns in the development of today's supercomputers. To build a powerful machine while at the same time satisfying reliability requirement and energy constraint, HPC scientists continue to seek a better understanding of system and component behaviors. Toward this end, modern systems are deployed with various monitoring and logging tools to track reliability and energy data during system operations. Since these data contain important information about system reliability and energy, they are valuable resources for understanding system behaviors. However, as system scale and complexity continue to grow, the process of collecting system data to extracting meaningful knowledge out of overwhelming reliability and energy data faces a number of key challenges. To address these challenges, my work consists of three parts, including data preprocessing, data analysis and advanced modeling.
Ph.D. in Computer Science, December 2015
Show less

Title: Load Redistribution Attacks and Protection Strategy Design in Electric Power Systems
Creator: Yuan, Yanling
Date: 2012-04-27, 2012-05
Description: Electric power systems have evolved over the past century to the largest and the most complex cyber-physical systems. With the development of...
Show moreElectric power systems have evolved over the past century to the largest and the most complex cyber-physical systems. With the development of Smart Grid, cyber security has become an area of growing concern. False data injection attack has recently attracted wide research interest. This thesis develops the concept of load redistribution attack, a special type of false data injection attack. The physical and economic impact of load redistribution (LR) attacks is quantitatively analyzed in this thesis. Since LR attacks can successfully bypass bad data detection and manipulate the state estimation outcome, security constrained economic dispatch (SCED) based on the false state estimation would lead the system into a non-optimal or insecure operation state. Based on the consequence analysis, two different attacking goals are differentiated from the adversary’s perspective, i.e., immediate attacking goal and delayed attacking goal. For the immediate attacking goal, a max-min attacker-defender model is proposed to identify the most damaging immediate LR attack. Two different algorithms are used to solve this bi-level optimization problem. For the delayed attacking goal, a tri-level model is proposed to identity the most damaging delayed LR attack. This thesis studies the economic impact of LR attacks on power market operation. A convex model is proposed under the mechanism of virtual bidding to compute the optimal injection of LR attack, which gains the most profit from the attackers’ perspective. The quantitative analysis of LR attacks provides an in-depth insight on effective attack prevention with limited protection resource budget. This thesis proposes a new protection strategy, which intends to mitigate the most damaging effect of LR attacks on power system operation. The criterion of determining effective protections against the most damaging LR attack, considering the existence of stochastic measurement errors, is deduced.
Ph.D. in Electrical Engineering, May 2012
Show less

Title: STRUCTURAL CHARACTERIZATION OF THE FLIGHT MUSCLE OF MANDUCA SEXTA
Creator: Cheng, Yu-shu
Date: 2013-04-22, 2013-05
Description: There are several properties of the flight muscle Manduca sexta that are interesting. In its physiological characteristics, like mammalian...
Show moreThere are several properties of the flight muscle Manduca sexta that are interesting. In its physiological characteristics, like mammalian skeletal and cardiac striated muscle, it is a synchronous muscle. However, it is much more similar structurally to the more widely known asynchronous insect flight muscles of Drosophila and Lethocerus. The goal of the thesis is to study the structural characteristics and perform mechanical studies of dorsal and ventral muscle of Manduca flight muscle. In pursuit of this goal, a secondary purpose was to develop better storage conditions for skinned insect muscle which can maintain muscle structure and function. Maximum active force as a function of time in storage was compared for storing at 4℃ without glycerol and storing at -80℃ with 75% glycerol. The maximum force values were almost the same during days 0-4. However, the muscle stored at -80℃ with 75% glycerol gave higher active force in high calcium (pCa 4.5) solution over a longer time in storage than muscle stored at 4℃. Both ventral and dorsal muscles can deliver 40-50% of original active force for up to 21 days in storage. X-ray diffraction experiments were done to compare the response of chemically skinned Manduca flight muscle to temperature and to the induction of rigor. The lattice spacing (d10) decreased and intensity ratio I20/I10 increased when the temperature of the relaxing solution bathing the solution increased from 10℃ to 40℃. Lattice spacing (d10) decreased, but the I20/I10 intensity ratio increased slightly while concentration of dextran increased from 1% to 6%. Six percent dextran was insufficient to restore the in vivo lattice spacing.
M.S. in Molecular Biochemistry and Biophysics, May 2013
Show less

Title: EFFECT OF NOVEL SANITIZERS IN COMBINATION WITH HIGH-POWER-ULTRASOUND ON MNV-ION ROMAINE LETTUCE
Creator: Zeng, Jin
Date: 2016, 2016-05
Description: Human norovirus is a leading cause of foodborne outbreaks around the world especially in fresh-cut products like romaine lettuce. Traditional...
Show moreHuman norovirus is a leading cause of foodborne outbreaks around the world especially in fresh-cut products like romaine lettuce. Traditional sanitizers such as sodium hypochlorite have been used in food industry to prevent contamination; however there are certain issues such as residuals and toxicity. Novel organic sanitizers have been developed and most of them have been proved not effective on human norovirus. High- Power-Ultrasound (HPU) has a potential to improve effectiveness of sanitizers for washing of fresh-cut produce. As a novel technology, HPU is a non-thermal processing that can enhance inactivating microorganisms in food. In the present study, we have systematically investigated the effect of sanitizers, Chico-wash, ProduceShield, Tsunami 100, EatCleaner and chlorine on human norovirus surrogate and the effect of HPU to enhance viral inactivation. For washing study, romaine lettuce leaves were cut into 5x5 cm2 pieces and spotinoculated with approximately 7 log PFU/ml of MNV-1. The leaves were washed for 60s, 90s, and 120s using various sanitizer concentrations. After washing, leaves were transferred into a stomach bag that contained 20ml of Dulbecco's modified eagle medium (DMEM) or phosphate buffer solution (PBS) containing 0.5M sodium thiosulfate to neutralize the sanitizers. Viruses were extracted by stomaching and recovered from the samples and quantified by viral plaque assay. Water wash without sanitizer was used as a negative control. For water wash, 1.1± 0.1 log PFU/g, 1.3 ± 0.1 log PFU/g and 1.3 ± 0.1 log PFU/g reduction were observed respectively under 60s, 90s and 120s washing.For 20% Chico-wash, under three different time intervals, MNV-1 reductions of 1.2 ± 0.1 log PFU/g, 1.1± 0.1 log PFU/g and 1.2 ± 0.2 log10 PFU/g were observed respectively. While for ProduceShield, at 20% concentration level, 1.5 log PFU/g, 1.6 log PFU/g and 1.6 log PFU/g reduction were observed respectively. For Tsunami 100, leaves were washed for 60s at different concentrations of 20, 40, 60, 80 and 100 ppm, the reduction of MNV-1 was 2.1 ± 0.2, 2.9 ± 0.3, 3.2 ± 0.3, 3.7 ± 0.2 and 3.7 ± 0.2 log PFU/g, respectively, on the surface of lettuce leaves. In HPU study, a high power ultrasound was introduced into washing step in combination with Tsunami 100 at concentrations of 20, 40, 60, 80, 100 ppm. The reduction of MNV-1 was 2.7 ± 0.3, 2.9 ± 0.5, 3.3 ± 0.7, 3.6 ± 0.7 and 3.8 ± 0.5 log10 PFU/g, respectively. For EatCleaner, lettuce leaves were washed for 60s and the reduction of MNV-1 was 1.9 ± 0.1 log10 PFU/g.The results suggest that Chico-wash and ProduceShield were not effective on removing MNV-1 from romaine lettuce while EatCleaner was effective. Tsunami 100 was effective on MNV-1. One-way ANOVA shows that introducing HPU could enhance MNV-1 inactivation at low Tsunami 100 concentration.
M.S. in Food Safety and Technology, May 2016
Show less

Title: AN ADAPTIVE RESCALING SCHEME FOR COMPUTING HELE-SHAW PROBLEMS
Creator: Zhao, Meng
Date: 2017, 2017-07
Description: In this thesis, we develop efficient adaptive rescaling schemes to investigate interface instabilities associated with moving interface...
Show moreIn this thesis, we develop efficient adaptive rescaling schemes to investigate interface instabilities associated with moving interface problems. The idea of rescaling is to map the current time-space onto a new time-space frame such that the interfaces evolve at a chosen speed in the new frame. We couple the rescaling idea with boundary integral method to demonstrate the efficiency of the rescaling idea, though it can be applied to Cartesian-grid based method in general. As an example, we use the Hele-Shaw problem to examine the efficiency of the rescaling scheme. First, we apply the rescaling scheme to a slowly expanding interface. In the new frame, the evolution is dramatically accelerated, while the underlying physics remains unchanged. In particular, at long times numerical results reveal that there exist nonlinear, stable, self-similarly evolving morphologies. The rescaling idea can also be used to simulate the fast shrinking interface, e.g. the Hele-Shaw problem with a time dependent gap. In this case, the rescaling scheme slows down the interface evolution in the new frame to remove the severe time step constraint that makes the long-time simulations prohibitive. Finally, we study an analytical solution to the stability of the interface of the Hele-Shaw problem, assuming a small surface tension under a time dependent flux Q(t). Following [116, 109], we find the motions of daughter singularity ζd and simple singularity ζ0 do not depend on the flux Q(t). We also find a criterion to identify the relation between ζ0 and ζd.
Ph.D. in Applied Mathematics, July 2017
Show less

Title: COOPERATIVE BATCH SCHEDULING FOR HPC SYSTEMS
Creator: Yang, Xu
Date: 2017, 2017-05
Description: The batch scheduler is an important system software serving as the interface between users and HPC systems. Users submit their jobs via batch...
Show moreThe batch scheduler is an important system software serving as the interface between users and HPC systems. Users submit their jobs via batch scheduling portal and the batch scheduler makes scheduling decision for each job based on its request for system resources and system availability. Jobs submitted to HPC systems are usually parallel applications and their lifecycle consists of multiple running phases, such as computation, communication and input/output data. Thus, the running of such parallel applications could involve various system resources, such as power, network bandwidth, I/O bandwidth, storage, etc. And most of these system resources are shared among concurrently running jobs. However, Today's batch schedulers do not take the contention and interference between jobs over these resources into consideration for making scheduling decisions, which has been identified as one of the major culprits for both the system and application performance variability. In this work, we propose a cooperative batch scheduling framework for HPC systems. The motivation of our work is to take important factors about jobs and the system, such as job power, job communication characteristics and network topology, for making orchestrated scheduling decisions to reduce the contention between concurrently running jobs and to alleviate the performance variability. Our contributions are the design and implementation of several coordinated scheduling models and algorithms for addressing some chronic issues in HPC systems. The proposed models and algorithms in this work have been evaluated by the means of simulation using workload traces and application communication traces collected from production HPC systems. Preliminary experimental results show that our models and algorithms can effectively improve the application and the system overall performance, HPC facilities' operation cost, and alleviate the performance variability caused by job interference.
Ph.D. in Computer Science, May 2017
Show less

Title: A HARDWARE-IN-THE-LOOP SOFTWARE-DEFINED NETWORKING TESTING AND EVALUATION FRAMEWORK
Creator: Yang, Qi
Date: 2017, 2017-05
Description: The transformation of innovative research ideas to production systems is highly dependent on the capability of performing realistic and...
Show moreThe transformation of innovative research ideas to production systems is highly dependent on the capability of performing realistic and reproducible network experiments. Simulation testbeds o↵er scalability, reproducibility but lack fidelity due to model abstraction and simplification, while physical testbeds o↵er high fidelity but lack reproducibility and often technically challenging and economically infeasible to perform large-scale experiments. In this work, we present a hybrid testbed consisting of container-based network emulation and physical devices to advocate high fidelity and reproducible networking experiments. In particular, the testbed integrates network emulators (Mininet) [5], a distributed control environment (ONOS) [1], physical switches (Pica8) and end-hosts (Raspberry Pi and commodity servers). The testbed (1) o↵ers functional fidelity through unmodified code execution on an emulated network, (2) supports large-scale network experiments using lightweight OS-level virtualization techniques and capable of running across distributed physical machines, (3) provides the topology flexibility, and (4) enhances the repeatability and reproducibility of network experiments. We validate the fidelity of the hybrid testbed through extensive experiments under di↵erent network conditions (e.g., varying topology and traffic pattern), and compare the results with the benchmark data collected on physical devices.
M.S. in Computer Science, May 2017
Show less

Title: NOVEL FAULT DIAGNOSTIC TECHNIQUE AND UNIVERSAL SENSOR FOR PERMANENT MAGNET ELECTRIC MACHINES USING SEARCH COILS
Creator: Da, Yao
Date: 2012-04-23, 2012-05
Description: Over the past decade, permanent magnet synchronous machines (PMSMs) have gained significant popularity in industry, such as wind turbines and...
Show moreOver the past decade, permanent magnet synchronous machines (PMSMs) have gained significant popularity in industry, such as wind turbines and electric vehicles, owing to their high efficiency, high output power to volume ratio, and high torque to current ratio. In these mission critical applications, an unexpected fault or failure of the machine could lead to very high repair or replacement cost, or even catastrophic system failure. Therefore a robust and reliable health monitoring and fault diagnostic approach is desired, which could help in scheduling preventive maintenance to lengthen their lifespan and avoid machine failure. This dissertation presents a novel multi-faults diagnostic approach using search coils. These search coils are wound around armature teeth, so they typically need to be installed during manufacturing. But its immunity to high frequency harmonics makes it suitable for inverter/rectifier fed motors or generators, such as wind turbines and automotive systems. In addition, this method does not require the knowledge of proprietary constructional details of the machine. Since the electromagnetic flux is directly measured in this method, it provides much more information than any other scheme: the direction of eccentricity and the location of shorted windings. Furthermore, this method is also capable of evaluating the severity of each fault, which is of significant importance in mission critical applications such as automotive, aerospace and military applications. In addition to these uses, the search coils can be used as a universal sensor to estimate phase current or rotor position, which are critical information in a PMSM close-loop control, which allow it to work as a backup sensor for fault tolerant operation. The proposed fault detection scheme and universal sensor concept have been tested under several scenarios with Finite Element Analysis and experimentally validated.
Ph.D. in Electrical Engineering, May 2012
Show less

Title: OPTIMIZATION AND MARKET CLEARING IN THE POWER SYSTEMS WITH HIGH-LEVEL RENEWABLES
Creator: Ye, Hongxing
Date: 2016, 2016-05
Description: The increasing penetration of renewable energy source (RES), such as wind and solar power generation, in recent years to meet various...
Show moreThe increasing penetration of renewable energy source (RES), such as wind and solar power generation, in recent years to meet various renewable portfolio standards (RPS) has led to more uncertainties in power systems. The RES penetration level is expected to further increase in order to reduce emission and fight climate change. The growing uncertainties caused by RES pose new challenges in power and energy systems. Advanced models and technologies are urgent to provide secure, affordable and clean energy to customers. Security-Constrained Unit Commitment (SCUC) problem is one of the most important tools in the modern power system. It determines the optimal short-term generating planning. The electricity is priced and settled based on its solution. In order to manage the uncertainties caused by renewables, it is urgent to develop new SCUC models and solution approaches. SCUCs considering the uncertainties have become a focus of research in recent years. The proposed optimistic robust SCUC combines the idea of robust optimization and reserve concept in the electricity. The merit of the robust optimization is that its solution can be immunized against any uncertainties. It exactly meets the first priority, reliability, in power system operation. The robust optimization is attractive in theory. However, a solution is robust if and only if the system can survive in the worst case scenario. Hence, the key task is to identify the worst case scenario. Unfortunately, finding the worst case scenario in general is a non-deterministic polynomial-time hard (NP-hard) problem. This will create issue in satisfying the timeliness requirement that the optimal scheduling must be obtained quickly (e.g., within several hours) in the day-ahead electricity markets. This dissertation proposes a fast solution approach to finding the worst case scenario by exploring the special structure in the SCUC problem. This dissertation proposes a new market mechanism for managing uncertain ties caused by high-level RES based on the robust optimization. A new concept, Uncertainty Marginal Price (UMP), is proposed to charge uncertainty sources and to credit flexible sources. For the first time, explicit price signals are provided and utilized to manage any level uncertainties within a robust optimization framework. The proposed mechanism manages uncertainties from both the source side (uncertainty reduction) and resource side (uncertainty accommodation). In short term, it provides incentives for RES operators to improve forecasting accuracy (i.e. to reduce uncertainties) and existing flexible resources (e.g. storage) to participate the uncertainty accommodation. In long term, the proposed mechanism provides price signals for siting new flexible resources (e.g. energy storage) to accommodate uncertainties from increasing RES penetration.
Ph.D. in Electrical Engineering, May 2016
Show less

Title: OPTIMAL SIGNAL TIMING DESIGN FOR URBAN STREET NETWORKS UNDER USER EQUILIBRIUM BASED TRAFFIC CONDITIONS
Creator: Liu, Yi
Date: 2015, 2015-05
Description: In the ever-growing travel demand, traffic congestion on freeways and expressways recurs more frequently at a higher number of locations and...
Show moreIn the ever-growing travel demand, traffic congestion on freeways and expressways recurs more frequently at a higher number of locations and for longer durations with added severity. This becomes especially true in large metropolitan areas. Particular to the urban areas, excessive crowdedness caused by inefficient traffic control also results in urban street networks operating in near or over-saturated conditions, leading to unpleasant travel experience due to long delays at intersections. As a consequence, the recurrent traffic congestion on roadway segments and vehicle delays at intersections inevitably compromise energy efficiency, traffic mobility improvement, safety enhancement, and environmental impacts mitigation. All too often, neither restraining travel demand nor expanding system capacity is desirable and practical. Conversely, effectively utilizing the capacity of the existing transportation system has been increasingly thought of as the solution to congestion relief. With respect to the urban street networks, developing effective means for urban intersection signal optimization becomes essential to reduce intersection delays. Conventional signal timing optimization methods use historical traffic data and assume that traffic flows will remains unchanged after the implementation of new signal timing plans. Traffic flows are assumed to be constant, but in fact, when signal timing plans change, travel times for some travel routes will alter, which requires drivers in the network to adjust their choice of travel routes to arrive at the destinations, and result in redistribution of traffic in the network. Therefore, the effects of interactions between signal timing plans and traffic flows need to be explicitly taken into consideration. This study introduces a new methodology that jointly considers signal timing optimization and traffic assignment in an overall analytical framework that contains model formulations under assumptions consistent with real world situations. Such a framework is well suited for applications in real world cases. Specifically, the overall optimization framework is formulated as a bilevel optimization problem. In the proposed basic model, at the upper level, a traffic signal timing optimization problem for urban network is introduced to minimize system total travel time by optimizing signal green splits. At the lower level, a static user equilibrium problem is formulated for networkwide traffic assignment. In the vehicle delay estimation, the time-dependent stochastic delay model in the 2010 Highway Capacity Manual (HCM 2010) is employed and formulated as Variational Inequality constraints, what allow the state-of-the-art MPEC solver, GAMS/NLPEC, to solve the problem for a local optimal effectively and efficiently. The bi-level optimization model is first tested using a small network (the test network) and a computational experiment using a subarea network in the Chicago central district is conducted to assess the practicality of the model formulation in real world applications. In order to import more reality to the basic model and also consider the potential system benefit that comes from different signal phasing design, an enhanced model is developed based on the basic model by employing integer and binary variables. Formulating the problem with binary variables allows for the selection of proper phasing design. Heuristic solution methods are proposed and tested using the test network.
Ph.D. in Civil Engineering, May 2015
Show less

Title: A REVIEW OF ORTHOGONAL LATIN HYPERCUBE DESIGNS FOR COMPUTER EXPERIMENTS
Creator: Jiang, Yin
Date: 2014, 2014-05
Description: Computer models can describe complicated physical phenomena. Due to the highly nonlinear and complex nature, they require specially designed...
Show moreComputer models can describe complicated physical phenomena. Due to the highly nonlinear and complex nature, they require specially designed experimental inputs. One direction of computer experiment design is orthogonal Latin hypercube design which is widely used. This thesis reviews the most resent methods of orthogo- nal Latin hypercube designs, their constructing algorithms and important theoretical properties. These designs are easy to construct and preserve the orthogonal and equally-spaced projections. With large number of factors, orthogonal Latin hyper- cube designs enable researchers to estimate uncorrelated rst-order regression e ects, as well as higher-order e ects. For large number of runs, we reviewed general design method to construct large orthogonal Latin hypercubes from small orthogonal Latin hypercubes. A similar construction method for nearly orthogonal Latin hypercubes was discussed as well.
M.S. in Applied Mathematics, May 2014
Show less

Title: PSYCHOMETRIC PROPERTIES OF THE CENTER FOR EPIDEMILOGICAL STUDIES DEPRESSION SCALE (CES-D) USED AMONG NATIVE CHINESE INDIVIDUALS WITH SPINAL CORD INJURY
Creator: Xiong, Ying
Date: 2014, 2014-07
Description: Depressive symptoms are highly prevalent among people with Spinal Cord Injury (SCI) and yet there is a lack of consensus over psychometrically...
Show moreDepressive symptoms are highly prevalent among people with Spinal Cord Injury (SCI) and yet there is a lack of consensus over psychometrically sound diagnostic criteria or screening tools for depression. This is particularly true with the SCI population in China. Currently, there is limited information regarding the prevalence of depression, severity, and depressive symptomatology among individuals with SCI in China. CES-D lOis a simple and quick tool to use, and it avoids over-estimating depression due to frequent somatic complaints associated with SCI. To our best knowledge, the CES-D 10 had not been used among the native Chinese population with SCI. The current study used the CES-D 10 to measure depressive symptoms among individuals with SCI in China. The purpose ofthis study was to examine factorial validity, internal consistency, construct validity, and concurrent validity ofCES-D 10 among 260 Chinese individuals with SCI. Results showed an alarmingly high prevalence of depressive symptoms among the sample. Consistent with existing literature and hypotheses, a two-factor structure of CES-D 10 was replicated based on a confirmatory factor analysis. Hierarchical regression analyses showed several important psychosocial constructs such as acceptance of disability, social support, and functional disability were predictors of overall depressive symptoms. Surprisingly, depressive symptoms were not predictive of employment status. The scale showed low internal consistency, and a cultural response bias in which participants are less likely to endorse positively-stated CES-D items among the current sample. Such finding is consistent with past studies among the East Asian population. Limitations and implications ofthe study were discussed.
Ph.D. in Psychology, July 2014
Show less

Title: CAPACITY BOUNDS FOR LARGE SCALE WIRELESS SENSOR NETWORKS
Creator: Tang, Shaojie
Date: 2012-11-20, 2012-12
Description: We study the network capacity of large scale wireless sensor networks under both Gaussian Channel model and Protocol Interference Model. To...
Show moreWe study the network capacity of large scale wireless sensor networks under both Gaussian Channel model and Protocol Interference Model. To study network capacity under gaussian channel model, we assume n wireless nodes {v1, v2, · · · , vn} are randomly or arbitrarily distributed in a square region Ba with side-length a. We randomly choose ns multicast sessions. For each source node vi, we randomly select k points pi,j (1 ≤ j ≤ k) in Ba and the node which is closest to pi,j will serve as a destination node of vi. The per-flow unicast(multicast) capacity is defined as the minimum data rate of all unicast(multicast) sessions in this network. We derive the achievable upper bounds on unicast capacity and a upper bound(partial achievable) on multicast capacity of the wireless networks under and Gaussian Channel model. We found that the unicast(multicast) capacity for wireless networks under both two models has three regimes. Under protocol interference model, we assume that n wireless nodes are randomly deployed in a square region with side-length a and all nodes have the uniform transmission range r and uniform interference range R > r. We further assume that each wireless node can transmit/receive at W bits/second over a common wireless channel. For each node vi, we randomly pick k − 1 nodes from the other n − 1 nodes as the receivers of the multicast session rooted at node vi. The aggregated multicast capacity is defined as the total data rate of all multicast sessions in the network. In this work we derive matching asymptotic upper bounds and lower bounds on multicast capacity of large scale random wireless networks under protocol interference model.
PH.D in Computer Science, December 2012
Show less

Title: STUDY ON EX POST PRICING
Creator: Zhao, Zhechong
Date: 2011-05-02, 2011-05
Description: The main objective of this thesis is to study the ex post pricing in electricity market by implementing two new methods (quantity based method...
Show moreThe main objective of this thesis is to study the ex post pricing in electricity market by implementing two new methods (quantity based method and price based method). The quantity based method measures the difference between the actual performance of an individual resource and its bid-based profit-maximizing response to the ex post prices. The price based method measures the different between the ex post price and the supporting price which supports the actual outputs. These two methods are based on a co-optimization market for energy and ancillary service. They are very flexible and can solve the ex post price efficiently and simultaneously.
M.S. in Electrical Engineering, May 2011
Show less

Title: PSYCHOSOCIAL FACTORS RELATED TO READING FLUENCY DURING THE TRANSITION FROM ORAL TO SILENT READING
Creator: Dreher, Taylor
Date: 2014, 2014-05
Description: The present study investigated how reading fluency is related to social desirability and academic self-concept during a critical period in...
Show moreThe present study investigated how reading fluency is related to social desirability and academic self-concept during a critical period in reading development for children. It was predicted that social desirability would be a better predictor of oral reading fluency, while academic self-concept would be a better predictor of silent reading fluency. Participants were sixty third-grade students from Catholic schools in a large metropolitan area. All children completed measures of oral reading fluency, silent reading fluency, academic self-concept, and social desirability. Multiple regression and dominance analysis supported the hypothesized relationships. Social desirability had a significant negative relationship with oral reading fluency, while academic self-concept was unrelated to oral reading fluency. In addition, academic self-concept had a significant positive relationship with silent reading fluency, while social desirability had a smaller, but still significant, negative relationship with silent reading fluency. The present findings suggest that psychosocial factors like social desirability and academic self-concept may help identify children who are at risk for reading underachievement. Future research should use a longitudinal design to examine if measuring social desirability and academic self-concept in third grade can predict important outcomes, such as reading fluency in fourth grade or beyond.
M.S. in Psychology, May 2014
Show less

Title: MULTI-DIMENSIONAL BATCH SCHEDULING FRAMEWORK FOR HIGH-END SUPERCOMPUTERS
Creator: Zhou, Zhou
Date: 2016, 2016-05
Description: In the field of high performance computing (HPC), batch scheduling plays a critical role. They determine when and how to process the various...
Show moreIn the field of high performance computing (HPC), batch scheduling plays a critical role. They determine when and how to process the various jobs waiting for service. Conventional batch schedulers allocate user jobs solely based on their CPU footprints. However, for a given user job, it requires many different resources during its execution, such as power, network, I/O bandwidth, etc. Today’s job schedulers rarely take into account these resource requirements which sometimes turn out to be the Achilles’ heel of system-wide performance. In this research, we propose a multi-dimensional batch scheduling framework for high-end supercomputers. Our research aims to treat these common but often ignored resources (e.g., power, network, bandwidth) as schedulable resource and further transform each scheduling into a multi-objective optimization process. Our main contributions consist of a set of scheduling models and policies, aiming at addressing the issues in batch scheduling for large-scale production supercomputers. We evaluate our design by means of trace-based simulations using real workload and performance traces from production systems. Experimental results show our methods can effectively improve batch scheduling regarding user satisfaction, system performance and operating cost.
Ph.D. in Computer Science, May 2016
Show less

Title: PULSED LIGHT INACTIVATION OF MURINE NOROVIRUS ON VARIOUS FOOD CONTACT SURFACES
Creator: Zhou, Zijin
Date: 2015, 2015-07
Description: Norovirus is one of the leading causes for foodborne illness. Transmission of virus from surface to food has been known to cause a number of...
Show moreNorovirus is one of the leading causes for foodborne illness. Transmission of virus from surface to food has been known to cause a number of outbreaks. Studies of norovirus have been conducted using Murine Norovirus to simulate the behaviors. Pulsed light (PL) is a promising surface decontamination technology, which has the potential to be applied in a food service setting. PL uses intense pulses of short duration and a broad spectrum to accomplish microbial inactivation. This study evaluates the effect of PL on MNV-1, artificially inoculated onto various food contact surfaces including 304 stainless steel, glazed tile, polypropylene, and ultra-high molecular weight (UHMW) polyethylene. The virus was allowed to inoculate on the coupons for 20mins and treated with PL in a Xenon Steripulse XL-3000TM pulsed light treatment system for up to 60 s, at a distance of 8.3 cm 10.8 cm or 13.3cm from the central axis of the lamp. An infrared (IR) camera was used to record surface temperatures, in 1-s increments. After PL treatments, remaining viruses were recovered from surfaces and quantified by plaque assay. At a distance of 10.8cm, MNV-1 was reduced by 2.22-, 2.27- 2.75- and 3.12-log, after 20s treatment on inoculated stainless steel, glazed tile, UHMW polyethylene and polypropylene, respectively. After 50s treatment, MNV-1 was reduced by 4.86- and 5.93- log on glazed tile and stainless steel surface respectively. The surface temperature on tile and stainless steel increased at the rate of 1.08±0.20 and 1.28±0.32°C /s respectively. A relatively short treatment using pulsed light is sufficient to inactivate MNV-1 on the surface of materials commonly used in food preparation. The results suggest that the technology has the potential to reduce surface viral contamination in a food preparation setting.
M.S. in Food Safety and Technology, July 2015
Show less

Title: Optimal Behavior Modeling and Analysis of Electricity Market Participants
Creator: Li, Jie
Date: 2012-04-27, 2012-05
Description: n restructured electricity power markets, competition among market participants is a key issue of concern for both the ISO (Independent System...
Show moren restructured electricity power markets, competition among market participants is a key issue of concern for both the ISO (Independent System Operator) and the market participants themselves. This dissertation analyzes the market behavior of both the generation side and demand side participants, and provides solution guidelines for devising effective competition strategies for market players’ profit maximization objectives. Generation side is the most competitive part in the electricity market with the unbundling of generation, transmission and distribution. Acting as self-interested entities, GENCOs (Generation Companies) are seeking effective and computationally efficient methodology for generation resource scheduling, while keeping its financial risks at acceptable levels when constituting bidding strategies. To help GENCOs achieve such goal, this dissertation propose a game theory based supply function like bidding model to construct the optimal bidding strategies for GENCOs in both energy and ancillary service markets. On the demand side, demand participation in the electricity market has already been advocated for a long time for its benefit to the entire market and the society as a whole. This dissertation focuses on a specific large electricity consumer type – Internet Data Center (IDC). By analyzing the unique energy consumption pattern for different IDC applications, this dissertation devises effective electric demand management solution for IDCs to conserve electricity energy consumption and cut electric bill, and quantifies the demand response effect of IDC on the electricity market.
Ph.D. in Electrical Engineering, May 2012
Show less

Title: VIEW SYNTHESIS OF THREE DIMENSIONAL VIDEOS USING VIDEO PLUS DEPTH
Creator: Loghman, Maziar
Date: 2012-07-02, 2012-05
Description: This thesis investigates the use of segmentation in view synthesis for three- dimensional video. View synthesis is the process of generating...
Show moreThis thesis investigates the use of segmentation in view synthesis for three- dimensional video. View synthesis is the process of generating novel views of a scene, using set of views as the reference. Recently, several techniques have been suggested that use the depth maps for rendering virtual views. However, inaccuracy in depth maps causes annoying visual artifacts in depth-based view synthesis. This thesis presents an e cient depth image-based rendering technique based on segmentation using multi-level thresholding. In the proposed algorithm, rst all the images are segmented according to the depth and the pixels belonging to di erent objects are warped and blended independently. Based on multi-level thresholding, an algorithm for nding the ghost contour pixels is provided which simpli es the computations. A novel method for inpainting for disocclusions is introduced which uses the segmented images to nd the associated background boundary pixels. The experimental results show that the proposed algorithm improves the PSNR of the synthesized views up to 0:68 dB for the multi-view video test sequences and eliminates the annoying artifacts.
M.S. in Electrical Engineering, May 2012
Show less

Title: AN ANALYTICAL MODEL FOR SWITCHED RELUCTANCE MACHINE WITH HIGHER NUMBER OF ROTOR POLES
Creator: Jia, Yijiang
Date: 2012-05-08, 2012-05
Description: With growing interest in renewable energy technology and hybrid electric vehi- cle systems owing to environmental concerns and depleting...
Show moreWith growing interest in renewable energy technology and hybrid electric vehi- cle systems owing to environmental concerns and depleting fossil fuel reserves, electric machines have received widespread attention as a key component in the successful im- plementation of high efficiency drives. Towards this goal, the last two years have seen a significant increase in research in permanent magnet-alternative machine topologies. This has primarily been because of growing concerns over foreign dependence for rare- earth materials and a dramatic increase in the cost of permanent magnets. Switched Reluctance Machine (SRM) has been one of the leading contenders in this category. It does not require any permanent magnets, and is very suitable for operation in harsh operating environments. Furthermore, this machine has simple construction and is highly fault-tolerant with one of the widest operating speed ranges. Nowadays, it has found wide application in the automotive, aerospace as well as domestic area. How- ever conventional SRM suffers from modeling complexity and torque ripple during the phase commutation with the same origin. Using the novel PD formula proposed at the Illinois Institute of Technology, a new family of machines has been developed with a significant improvement in torque ripple. Owing to its novel configuration, analytical models for the design of advanced driver system design have also not been developed. In this study, an analytical model for the novel 6/10 SRM has been proposed. The machine model is characterized using an inductance model utilizing truncated Fourier series as well as multi-order polynomial curve-fitting algorithm. The induc- tance model is extended to back-EMF and electromagnetic torque models on purpose of obtaining the whole information for every single operating point of the machine during dynamic operation. The effectiveness of the proposed concept has analyzed for a prototype machine in the laboratory and verified using Finite Element Analysis. From this study, an algorithm has been proposed to develop the analytical model for the family of SRMs with higher number of rotor poles.
M.S. in Electrical Engineering, May 2012
Show less

repository.iit

Search the repository

Pages

Pages