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Title: HARDWARE-EFFICIENT VLSI IMPLEMENTATION FOR PARALLEL LINEAR-PHASE DIGITAL FIR FILTER
Creator: Tsao, Yu-chi
Date: 2011-11, 2011-12
Description: Along with the explosive growth of multimedia applications, the number of gates required and the area consumed in very-large-scale integration...
Show moreAlong with the explosive growth of multimedia applications, the number of gates required and the area consumed in very-large-scale integration (VLSI) for digital signal processing (DSP) is getting higher and higher. Therefore, the demand for low-complexity and low-cost VLSI architectures for DSP, which occupies area as small as possible while remaining high performance, is imperatively needed. Finite impulse response (FIR) digital filter is one of the most widely used fundamental devices performed in DSP systems, ranging from wireless communications to video and image processing. Furthermore, when narrow transition band characteristics are required, the much higher order in the FIR filter is unavoidable. For instance, a 576-tap digital filter is used in video ghost canceller for broadcast television, which reduces the effect of multi-path signal echoes. On the other hand, parallel and pipelining processing are two techniques used in DSP applications, which both can be exploited to reduce the power consumption. Parallel processing applied on FIR digital filter can either increase the throughputs for high-speed processing or reduce the power consumption of the original sequential filter by lower supply voltage. Hence, there have been several architectures for parallel FIR digital filter proposed in the past. However, for symmetric convolutions, linear phase digital FIR filter, these proposed architectures are not beneficial in terms of hardware consumption. In this dissertation, new parallel FIR digital filter architectures which can save significant hardware cost by exploiting the inherent nature of symmetric convolutions, namely linear phase digital FIR filter, are presented. This dissertation is mainly divided into four chapters. In chapter one, some prerequisites as the background related to parallel finite impulse response (FIR) digital xi filter design and implementation are introduced, including conventional parallel FIR digital filter architectures, parallel FIR digital filter structures based on fast FIR algorithm (FFA), previously proposed architectures for parallel FIR filter, maximum absolute difference (MAD) quantization algorithm, canonic signed digit (CSD) representation and CSD multipliers for constant multiplications, are introduced and reviewed. In chapter two, the proposed parallel FIR digital filter structures for symmetric convolutions of even length are presented, in which the complexity and experimental results are analyzed and compared with FFA-based parallel FIR digital filter and other previously proposed structures. In chapter three, the proposed parallel FIR digital filter architectures for symmetric convolutions of odd length are presented, in which the complexity and the benefit of structures are analyzed and compared with FFA-based parallel FIR digital filter and other previously proposed structures The last chapter, chapter four, gives the summary and the conclusion of the proposed parallel linear-phase FIR digital filter.
Ph.D. in Electrical Engineering, December 2011
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Title: PARTICLE FILTERING ESTIMATION APPROACH IN ADVANCED DIGITAL COMMUNICATION SYSTEMS
Creator: Huang, Lun
Date: 2013, 2013-05
Description: The ever-increasing volume of users and the demand for more communication services bring about many advanced modulation and demodulation...
Show moreThe ever-increasing volume of users and the demand for more communication services bring about many advanced modulation and demodulation technologies which are developed to increase the spectrum efficiency and cope with challenging transmission conditions in digital communications. However, it is difficult to improve the performance of those traditional modulation and demodulation approaches without increasing transmit power and lowering spectrum efficiency. This thesis studies the application of powerful Particle Filtering methods to the problems associated with the interference cancellation, equalization, demodulation, and decoding of the signals over communication channel. In this thesis, theoretic models of using particle filtering approaches in digital communications are investigated, and several specific algorithms and schemes are considered as applications of the theoretic models. First, the application of particle filtering in delayed decision feed-back sequence estimation equalization is addressed. The particle filtering approach is then introduced to an efficient particle filtering receiver for inter-carrier interference cancellation and demodulation of M-ary modulated signals in OFDM/OFDMA system under time-variant Rayleigh fading channels. Subsequently, an efficient sequential Monte Carlo (SMC) demodulation approach for Polynomial Phase Modulation (PPM) is discussed. The interference cancellation and demodulation algorithm for MIMO-PPM scenario is then derived. The analysis of performance and computational complexity for SMC particle filtering approach is also provided. Comprehensive simulation results confirm that the proposed sequential Monte Carlo particle filtering approaches have better performance than the conventional methods.
PH.D in Electrical Engineering, May 2013
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Title: EXPANDING FAITH-BASED ORGANIZATIONS’ ADAPTATION OF STREAMING TECHNOLOGY
Creator: Johnson Winston, Patty D.
Date: 2011-07-18, 2011-05
Description: In the field of technical communication there exist few studies that specifically address faith-based organizations’ use of communication...
Show moreIn the field of technical communication there exist few studies that specifically address faith-based organizations’ use of communication technology. The purpose of this dissertation was to show how these organizations can expand their use of streaming technology by using principles and practices that are common in technical communication. This was addressed in three phases. First, a review of the relationship between religion and media was conducted. It revealed that faith-based organizations are early adaptors of communication technology. Communication technology is used to widely broadcast their organizational missions, tenets and goals. By accomplishing these tasks, faith-based organizations seek to educate and reinforce cultural norms, images, and belief systems among their adherents and attract new members. Second, an examination of theories and instructional practices found in technical communication was conducted. It was determined that adapting a learning-centered approach to instruction can be applied to a distance education model for faith-based education. Third, faith-based websites were analyzed to determine types and current uses of communication technology. It was established that most of the organizations that offer educational courses do not conduct them online, even if they already use streaming media for other purposes. The findings suggest that faith-based organizations’ use of streaming technology for educational purposes is an area of inquiry that should be further explored by technical communicators. Technical communication provides a rich array of disciplines from which to draw, such as Instructional Design, Information Architecture, and Usability.
Ph.D. in Technical Communication, May 2011
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Title: TECHNOLOGY INTEGRATION IN SCIENCE EDUCATION: A STUDY OF HOW TEACHERS USE MODERN LEARNING TECHNOLOGIES IN BIOLOGY CLASSROOMS
Creator: Gnanakkan, Dionysius Joseph
Date: 2017, 2017-07
Description: This multiple case-study investigated how high school biology teachers used modern learning technologies (probes, interactive simulations and...
Show moreThis multiple case-study investigated how high school biology teachers used modern learning technologies (probes, interactive simulations and animations, animated videos) in their classrooms and why they used the learning technologies. Another objective of the study was to assess whether the use of learning technologies alleviated misconceptions in Biology documented by American Association for the Advancement of Science. The sample consisted of eight teachers: four rural public school teachers, two public selective enrollment school teachers, and two private school teachers. Each teacher was followed for two Units of instruction. Data collected included classroom observations, field notes, student assignments and tests, teacher interviews, and pre-and post-misconception assessments. Paired t-tests were done to analyze the pre-post test data at a significance level of 0.05 and the qualitative data was analyzed using the constant comparative method. Each case study was characterized and then a cross-case analyses was done to find common themes across the different cases. Teachers were found to use the learning technologies as a tool to supplement instruction to visualize abstract processes, collect data, and explore abstract concepts and processes. Teachers were found to situate learning, use scaffolding and questioning and make students work in collaborative groups. The genetics, photosynthesis, and evolution misconceptions were better alleviated than cellular respiration. Student work that was collected demonstrated a superficial understanding of the concepts under discussion even when they had misconceptions. The teachers used the learning technologies in their classrooms for a variety of reasons: visual illustrations, time-saving measure to collect data, best way to collect data, engaging and fun for students and the interactive nature of the visualization tools and models. The study’s findings had many implications for research, professional development, teacher education, teaching practice, administrators, and learning technology developers. More detailed research within similar school settings (public, charter, and private) is needed to verify the common findings across the different cases in this study. An implication is that learning technology integration could be modeled with instructional scaffolds and questioning and incorporating higher order thinking tasks. Learning technology developers should consider the collaborative learning groups while developing these technologies.
Ph.D. in Science Education, July 2017
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Title: COORDINATED DRIVING IN CONNECTED AND AUTONOMOUS VEHICLE SYSTEM -- OPTIMAL ADVANCE LANE CHANGE ZONES AND COORDINATED PLATOON CAR FOLLOWING CONTROL
Creator: Gong, Siyuan
Date: 2017, 2017-07
Description: The connected and autonomous vehicle (CAV) system enables countless innovative coordinated driving approaches, such as coordinated lane change...
Show moreThe connected and autonomous vehicle (CAV) system enables countless innovative coordinated driving approaches, such as coordinated lane change and car-following in microscopic CAV control, and coordinated rounding and parking in macroscopic traffic flow guidance, which will improve the performance of our transportation system by enhancing traffic mobility, providing safe driving environment and reducing fuel consumption. Since the lane change and car-following behavior are indicated as crucial factors of traffic safety and efficiency, this dissertation focuses on developing the coordinated driving schemes in microscopic control and operation of lane change and car-following maneuvers. In particular, I develop an lane change zone optimization strategy and the coordinated platoon car-following control for a pure CAV platoon and a mixed platoon (i.e. mixed with human-drive vehicles and CAVs) respectively. This dissertation first explore the management strategy of the mandatory lane change near a two-lane highway off-ramp by optimizing the location of advance warning. The proposed approach considers that the area downstream of the advance warning includes two zones: the green and yellow zones corresponding to their respective most like lane change maneuvers. An optimization model is proposed to search for the optimal green and yellow zones. Traffic flow theory such as Greenshield model and shock wave analysis are used to analyze the impacts of the S-MLC and D-MLC maneuvers on the traffic delay. Numerical experiments indicate that the proposed optimization model can identify the optimal location to set the advance MLC warning nearby an off-ramp so that the traffic delay resulting from lane change maneuvers is minimized, and the corresponding capacity drop and traffic oscillation can be efficiently mitigated. Then, this research develops a novel car-following control scheme for a platoon of connected and autonomous vehicles on a straight highway. The platoon is modeled as an interconnected multi-agent dynamical system subject to physical and safety constraints. A constrained optimization based control scheme is proposed to ensure an entire platoon’s transient traffic smoothness and asymptotic dynamic performance. This dissertation develops dual based distributed algorithms to compute optimal solutions with proven convergence. Furthermore, the asymptotic stability of the unconstrained linear closed-loop system is established. These stability analysis results provide a principle to select penalty weights in the underlying optimization problem to achieve the desired closed-loop performance for both the transient and the asymptotic dynamics. By the motivation that CAVs and human-drive vehicles will co-exist on the road for a long period in the near future, the third part of this dissertation extends the pure CAV coordinated platooning control to the mixed flow environment. By integrating the Newell car-following model, a real-time curve matching algorithm is implemented to calibrate the ca-following model and anticipate the movement of human-drive vehicle by the real-time trajectory data. The constrained MPC are developed for each CAV platoon, considering their movement interaction through the human-drive vehicle platoon. Furthermore, this study provide a modified dual based distributed algorithm to improve convergence speed of the primal problem for the dual based distributed algorithm in Chapter 4. Several requirements of the penalty weights selection are provided by stability analysis under the unconstrained conditions. The numerical experiments based on field data will be conducted to illustrate the effectiveness and efficiency of the proposed the solution approach and the platoon control schemes.
Ph.D. in Civil Engineering, July 2017
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Title: HARDWARE/SOFTWARE CO-DESIGN PARTITIONING ALGORITHM FOR MACHINE VISION APPLICATIONS
Creator: Gonnot, Thomas
Date: 2017, 2017-05
Description: Advancements in FPGA technologies now allows the implementation of machine vision using hardware component rather than processors for...
Show moreAdvancements in FPGA technologies now allows the implementation of machine vision using hardware component rather than processors for increased efficiency. The combination of hardware and software implementations, however, can provide even more efficient results by combining the advantages of both technologies. This leads to the problem of partitioning the machine vision algorithms between hardware and software. The hardware/software partition problem is NP-hard, which means that a solution to the problem can be checked in polynomial time, but the time to find the solution is not predictable. Automated methods based on a genetic algorithm or discrete particle swarm optimization algorithm allow a designer to implement computer vision algorithms without concerns for the hardware/software partitioning. Their reliance on randomness to explore different partitioning selections, however, means that the optimum result might not be reached and that the processing time cannot be predicted. This dissertation introduces a model for image processing and computer vision algorithms in a set of elementary blocks, each of which is assigned one or more configuration. This configuration can be either hardware or software and is linked to the corresponding resource utilization and performance. A procedure is also introduced to allocate the different blocks to either hardware or software, and a cost function is defined to evaluate the relevance of the generated design. The implementation of the model and procedure allows for the partitioning of any image processing in polynomial time by checking various implementations and selecting the optimum solution. This thesis includes two test cases used to test the efficiency of the method. The shift-invariant features transform is used to demonstrate the viability of the partitioning results on an algorithm containing multiple image convolution operations in parallel. The neural network, on the other hand, is used to demonstrate the performances of the procedure when machine vision algorithm contains many blocks. Finally, this dissertation present a set of machine vision applications, such as object tracking, object recognition, optical character recognition, facial recognition, and visually impaired assistance. The proposed model and procedure could be included in the design flow of hardware/software co-design tools and provide a library of image processing blocks ready to be implemented. This would allow image processing and computer vision designers would be able to implement any algorithm efficiently in hardware/software co-design without the need to know how to partition it.
Ph.D. in Electrical Engineering, May 2017
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Title: ADVANCES IN VEHICLE-TERRAIN INTERACTION MODELING FOR SMALL, RIGID-WHEELED VEHICLES OPERATING ON DEFORMABLE TERRAIN
Creator: Meirion-griffith, Gareth
Date: 2012-04-22, 2012-05
Description: This thesis presents advances in the eld of terramechanics, the study of ve- hicle mobility performance, for small, rigid-wheeled vehicles...
Show moreThis thesis presents advances in the eld of terramechanics, the study of ve- hicle mobility performance, for small, rigid-wheeled vehicles operating on deformable terrain. Speci cally, the thesis proposes new models for vehicle performance model- ing through the development of novel pressure-sinkage equations. The semi-empirical equations of terramechanics, rst developed by Bekker in the 1950s, couple vehicle mobility systems and terrain geotechnical properties to yield an understanding of the manner in which traction is developed o -road. This is important because on de- formable terrain mobility is often limited not by the vehicle's torque or power, but by the strength of the terrain and its ability to support locomotion. Classical terramechanics models have proven to be instrumental in the design, modeling, and operation of large, man-driven vehicles for applications such as agri- cultural, military, and commercial transport. However, these models are not appro- priate for vehicles with wheels less than approximately 50 cm in diameter [MGS11a] [SMGSM08] [RBC02]. This is a critical problem because of the increasing prolifer- ation of small, robotic vehicles. In particular, space agencies such as the National Aeronautics and Space Administration (NASA), the Japanese Aerospace Exploration Agency (JAXA), and the European Space Agency (ESA) have shown great interest in the application of terramechanics to planetary exploration rover mobility. At the inception of the author's research, several independent sources had noted the limited accuracy of classical terramechanics models for small-wheeled vehi- cles. However, an understanding of the cause of these inaccuracies was absent. This thesis provides an understanding of these inaccuracies, their cause, and a solution. Using laboratory experiments, fi eld test data, theoretical development, and vehicle simulation, this thesis proposes a modi fied terramechanics framework for predicting small, rigid-wheel traction.
Ph.D. in Mechanical and Aerospace Engineering, May 2012
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Title: CAPACITY ANALYSIS OF MULTI-RADIO MULTI-CHANNEL (MR-MC) WIRELESS NETWORK
Creator: Li, Hongkun
Date: 2012-11-15, 2012-12
Description: The multi-radio multi-channel (MR-MC) networking provides a generic computing platform for a wide range of next-generation wireless networks,...
Show moreThe multi-radio multi-channel (MR-MC) networking provides a generic computing platform for a wide range of next-generation wireless networks, e.g., wireless mesh networks based on the IEEE 802.16, 4G cellular networks based on the long term evolution (LTE), and cognitive radio networks based on the dynamic spectrum sharing. Multiple radio interfaces and channels allow more flexible network configuration to achieve higher network capacity. However, the capacity of the MR-MC networking is not well studied due to the lack of effective tool addressing the complex interactions of the channel assignment and radio interface allocation problem. Moreover, how to efficiently utilize multiple interfaces and channels is unexplored. Generally, we have the four main contributions in this work. 1) an efficient methodology is proposed to compute the optimal capacity of MR-MC network and the concept of critical set is revealed. 2) two sufficient conditions are developed for the flow assignment, which can be constructed and verified in distributed manner. Both conditions achieve a provable portion of the optimal capacity region. 3) a novel framework and efficient algorithms are developed for the dynamic network control in the MR-MC network. 4) a new routing metric is proposed to consider both delay and interference for path selection, and a routing protocol is designed correspondingly. Specifically, we originally construct a new multi-dimensional conflict graph (MDCG) to describe all the interference relationship in the MR-MC network. Based on MDCG, we formulate a multi-commodity flow (MCF) problem augmented with maximal independent set (MIS) constraint to compute the optimal capacity, so that the optimal capacity planning in MR-MC networks can be transformed from integer programming regime to linear programming regime. We further provide the new concept of critical MIS set, and estimate the upper bound of the size of critical MIS set. Therefore, a heuristic algorithm is designed to systematically compute those MISs, which are more likely to be involved in critical set. Moreover, we develop the sufficient conditions for the flow rate assignment, which achieve viii a provable portion of the optimal capacity region, termed as efficiency ratio. These sufficient constraints could be constructed and verified in the distributed and localized manner. We develop new method to compute the efficiency ratio for each sufficient condition by exploring the disruptively different geometric property of MR-MC networks compared with single radio single channel network. Then we develop a new framework to systematically study the resource allocation problem considering the dynamic network control in the MRMC network. The framework not only facilitates the formulation of throughput-optimal scheduling for the MR-MC network, but also allows us optimally solving the joint resource allocation problem, including routing, channel/interface assignment, flow allocation and scheduling. At last, a new routing metric is proposed to consider not only the transmission delay also queuing delay. In addition, in the MR-MC context, the inter-flow interference and intra-flow interference are taken into account. An AODV-based routing protocol is designed to implement the new metric.
PH.D in Electrical and Computer Engineering, December 2012
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Title: CHILD TEMPERAMENT AND PARENTING BEHAVIOR AT AGE 5: DO THEY PREDICT CHILD COPING AT AGE 6?
Creator: Hwang, Maria D’aniello
Date: 2014, 2014-07
Description: Coping has been shown to be related to many positive outcomes in children, including better psychological adjustment, positive social...
Show moreCoping has been shown to be related to many positive outcomes in children, including better psychological adjustment, positive social relationships and higher achievement. Additionally, coping abilities in childhood and adolescence can serve as risk or protective factors for psychopathology. Both parenting and child temperament have been shown to be related to child coping; however, these variables have never been examined simultaneously. The transition from kindergarten to grammar-school is considered to be important because children must learn to adjust to this critical, more structured environment. As a result, it is important to determine what factors contribute to adaptive coping at the time when children begin formal school. The aim of this study was to: (a) examine the relationship between child negative affect (NA), effortful control (EC), parenting variables (support/scaffolding, support/engagement, and hostility/coercion), and child coping; and (b) to determine if parenting moderates the effects of temperament on adaptive coping. Participants included 796 (391 males and 405 females) children and their primary caregivers. Children were assessed at ages 5 and 6 years. NA and EC were assessed by parent-report with the Child Behavior Questionnaire. EC also was assessed with an observer-rated task, Gift Delay, which measures the child’s ability to delay a prepotent response, and with two subtests from the NEPSY; Knock and Tap, and Statue. Parenting variables (support/engagement and hostility/coercion) were assessed by parent-report with the Parenting Behavior Inventory and through an observation task, which was assessed by a factor-analyzed composite of variables rated during the National Institute for Child Health and Human Development 3-Boxes Task (support/scaffolding). Coping adaptability was assessed using the Early Childhood Coping Puppet Interview. Results of hierarchical regression analyses indicated that NA, EC, support/scaffolding, support/engagement, and hostility/coercion were not related to child coping adaptability. There also was no evidence of moderation of the relationship between temperament and coping by parenting. Post hoc analyses indicated that for males, lower SES was related to more adaptive coping. Implications of these findings and suggestions for further research are discussed.
Ph.D. in Psychology, July 2014
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Title: AN EVALUATION OF THE FEASIBILITY OF AN ONLINE FAMILY-BASED INDICATED PREVENTION PROGRAM FOR ADOLESCENT EATING DISORDERS
Creator: Lebow, Jocelyn R.
Date: 2011-10, 2011-12
Description: Adolescent eating disorders are highly impairing class of mental illness, marked by chronicity and recurrence. Data indicate that early...
Show moreAdolescent eating disorders are highly impairing class of mental illness, marked by chronicity and recurrence. Data indicate that early intervention, before anorexia nervosa (AN) or bulimia nervosa (BN) symptoms become entrenched, leads to an increased likelihood of positive outcomes (Fisher, Schneider, Burns, Symons & Mandel 2001; Le Grange, Loeb, Van Orman & Jellar, 2004). As such, numerous prevention programs have been developed for adolescent eating disorders, with mixed success (Shaw, 2008, Stice, Shaw & Marti, 2007). Most recently, programs have utilized the technology of the Internet to make prevention and early intervention more accessible and cost effective for affected teens and families. The current study assessed the feasibility of an original Internet-based indicated prevention program for families of adolescents with subsyndromal eating disorders. The program was based on the empirically-supported Family Based Treatment (FBT) for adolescent AN and BN. Seven families (comprised of 7 caregivers and 7 adolescents with subthreshold levels of eating disorder symptoms) were enrolled in the study, and 4 families successfully completed all program requirements. Four separate aims were assessed including: evaluation of program acceptability, identification of recruitment and retention patterns, assessment of program compliance and dosage received, and analysis of preliminary outcomes. Results suggested that the program was acceptable to all participants, and that the program format and content were positively received. Preliminary outcome data was limited due to the small sample size, however, descriptive analyses showed that the program had a significant effect on the reduction of all cognitive and behavioral eating disorder symptoms, as well as on the reduction of adolescent depressive symptoms. Adolescent ix self esteem was not significantly impacted by program participation. Compliance results were less straightforward. Program adherence was mixed, and further investigation is needed to clarify patterns of compliance and retention. Finally, the recruitment strategies used were found to not be feasible. Despite a wide-ranging and multi-faceted recruitment strategy, rates were very slow. Further, a large percentage of interested potential participants had to be excluded, calling into question the appropriateness of the applicant pool that was accessed through the implemented program of recruitment. Implications of these findings, possible explanations and suggestions for future research are discussed.
Ph.D. in Psychology, December 2011
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Title: ESSAYS IN ENVIRONMENTAL FINANCE
Creator: Li, Jing
Date: 2013, 2013-07
Description: The Clean Development Mechanism (CDM) is a mechanism de ned in the Ky- oto protocol that incentivizes parties to the protocol to fund...
Show moreThe Clean Development Mechanism (CDM) is a mechanism de ned in the Ky- oto protocol that incentivizes parties to the protocol to fund sustainable development projects in countries that are not party to the protocol. In the rst chapter of this paper, I introduce the CDM and how the nancing mechanism works. In the second chapter, I analyze a target contract nancing structure for di erent CDM projects in order to see under what conditions the nancing structure is e cient and to explore the contract's allocation of pro t among the rms. In the two broad categories of CDM projects I consider, I nd the optimal investment decision for the investor and for the overall system. I also analyze how the residual value of technology would a ect the nancing, target contract's e ciency, and allocation of pro t. In the third chapter, I conduct empirical analysis on the actual CDM outputs, Certi ed Emission Reduction units (CERs), for a sample of wind CDM projects in China. I nd that CDM projects greatly under perform relative to the promises they make. Based on this under-performing records, in the fourth chapter, I analyze the economic bene ts investors could gain if they were able to directly fund a portfolio of CDM projects and obtain returns from the anticipated CER issuances and underlying energy generated from the portfolio of CDM projects. I consider a variety of funding constraints that the CDM fund/portfolio manager (CDM-PM) may face and determine their economic performance against actual CDM project data for wind CDM projects in China.
PH.D in Management Science, July 2013
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Title: STIGMA AND MENTAL ILLNESS: THE ROLE OF STEREOTYPE THREAT ON PERFORMANCE OF COGNITIVE MEASURES
Creator: Hautamaki, Julie Bilyeu
Date: 2013, 2013-05
Description: Deficits in cognitive functioning observed in people with schizophrenia are well-documented; however, social psychologists recognize that...
Show moreDeficits in cognitive functioning observed in people with schizophrenia are well-documented; however, social psychologists recognize that additional societal factors, such as stigma and discrimination, may further contribute to these observed deficits in functioning. This study investigated the role of stereotype threat on cognitive functioning of people with schizophrenia. This group encounters stigma in various realms such as employment, relationships and housing. The negative stereotypes regarding this population have been well-documented and studied. In the current study, 60 participants were randomized into a control or stereotype condition. The participants completed a series of cognitive tests and the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I). Participants in the stereotype threat condition were primed with a statement and questions to induce stereotype threat. The order of test administration was part of the threat induction. Stereotype threat was not found to impact the performance of cognitive measures for this group. In-group identification, stigma endorsement, and anxiety levels did not predict performance on cognitive measures.
PH.D in Psychology, May 2013
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Title: VISUAL TRAINING AT ILLINOIS INSTITUTE OF TECHNOLOGY: AESTHETICS IN ARCHITECTURAL EDUCATION
Creator: Jones, Kristin
Date: 2016, 2016-05
Description: Over the course of 78 years, an aesthetic ideal which embodies architectural values has been collectively cultivated through Visual Training...
Show moreOver the course of 78 years, an aesthetic ideal which embodies architectural values has been collectively cultivated through Visual Training at the Illinois Institute of Technology (IIT) school of architecture in Chicago. This dissertation provides a comprehensive explanation of Visual Training as it has been conducted at IIT. It promotes a better understanding of the background of Visual Training, the pedagogical practice of the Visual Training exercises, and the ongoing value of the course. The dissertation traces the underpinnings of Visual Training through the writings of Walter Peterhans, founder and Professor of Visual Training at IIT from 1938-1960, Ludwig Mies van der Rohe, Professor and Director of Architecture at IIT from 1938-1958 and other key figures. The thesis shows how the Visual Training program at IIT was influenced by movements in philosophy and mathematics in early 20th century Germany and how existing pedagogy at the Bauhaus was adapted to serve its aim. The dissertation includes an explanation of each exercise in the Visual Training program. It makes explicit the point of each exercise, how each one is conducted and why. Original detailed descriptions, illustrated with examples, show what a student gains from each exercise and how the process of performing the exercise achieves that end. The dissertation compares the way in which the Visual Training program originally developed in relation to other courses in the architecture curriculum to disclose the meaning of architecture, and what has happened in Visual Training as the architecture program at IIT has continued to evolve. The thesis brings to light enduring epistemological tensions underlying architectural education.
Ph.D. in Architecture, May 2016
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Title: Polymorphic Network-on-Chip Datapath Architecture for Reconfigurable Computing Machines
Creator: Weber, Joshua
Date: 2012-04-18, 2012-05
Description: Polymorphic processors have considerable advantages in performance over existing reconfigurable designs. Polymorphic processors combine the...
Show morePolymorphic processors have considerable advantages in performance over existing reconfigurable designs. Polymorphic processors combine the flexibility and ease of a general purpose processor with the performance optimizations made possible through reconfigurable arrays. Polymorphic processors provide all the ease of programming from a traditional general purpose processor while incorporating the significant performance gains that can be realized using reconfigurable arrays. Polymorphic processors can be categorized by the level of integration between the general purpose processor and the reconfigurable array. At coarse levels of integration, the processor and reconfigurable array execute independently and exchange data utilizing bus structures. These systems perform robustly for high level datadriven optimizations, allowing large segments of processing to be quickly performed on fast reconfigurable resources. However, the overhead of data transfer between the processor and array limits the benefit to fine grained optimizations. Other architectures attempt a tight coupling of reconfigurable arrays, placing them within the processor as reconfigurable coprocessors and functional units. This technique allows fine grained optimizations of small scale, highly repeated computations, but finds it difficult to replicate the gains made in large coarse grained optimizations. To achieve an even more tightly coupled design than any prior work, the fundamental architecture of the processor is changed. The datapath of the processor is eliminated and replaced with a network-on-chip communications framework. This framework connects a system of reconfigurable arrays. Some of these reconfigurable blocks are tasked with execution of standard, general purpose processor computations, emulating the standard pipeline stages of a SPARC processor. Additional reconfigurable blocks are available to the end-user to incorporate custom application specific optimizations. This new polymorphic NoC datapath (PolyNoC) processor is able to provide a more tightly integrated architecture with significant performance advantages. The PolyNoC processor is able to incorporate both fine and coarse grained optimizations, producing a polymorphic processor able to provide performance improvements for a wide range of target applications. This thesis presents the architectural design of the PolyNoC processor. The unique design constraints resulting from the use of the NoC as a datapath will be fully explored. The impact of these constraints will be incorporated into the design of a suitable NoC for the PolyNoC processor. A cycle-accurate simulator of the PolyNoC processor has been constructed. This simulator is used to examine the performance of the PolyNoC processor when executing unmodified, industry standard benchmark programs. To demonstrate the advantages of application specific extensions to the processor, accelerators are added for each benchmark. The performance of the Poly- NoC processor is promising.
Ph.D. Computer Science, May 2012
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Title: CYBER ATTACKS AGAINST STATE ESTIMATION IN POWER SYSTEMS: VUNERABILITY ANALYSIS AND PROTECTION STRATEGIES
Creator: Liu, Xuan
Date: 2015, 2015-07
Description: Power grid is one of the most critical infrastructures in a nation and could suffer a variety of cyber attacks. With the development of Smart...
Show morePower grid is one of the most critical infrastructures in a nation and could suffer a variety of cyber attacks. 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 proposes a false data attack model with incomplete network information and develops optimal attack strategies for attacking load measurements and the real-time topology of a power grid. The impacts of false data on the economic and reliable operations of power systems are quantitatively analyzed in this thesis. To mitigate the risk of cyber attacks, a distributed protection strategies are also developed. It has been shown that an attacker can design false data to avoid being detected by the control center if the network information of a power grid is known to the attacker. In practice, however, it is very hard or even impossible for an attacker to obtain all network information of a power grid. In this thesis, we propose a local load redistribution attacking model based on incomplete network information and show that an attacker only needs to obtain the network information of the local attacking region to inject false data into smart meters in the local region without being detected by the state estimator. A heuristic algorithm is developed to determine a feasible attacking region by obtaining reduced network information. This thesis investigates the impacts of false data on the operations of power systems. It has been shown that false data can be designed by an attacker to: 1) mask the real-time topology of a power grid; 2) overload a transmission line; 3) disturb the line outage detection based on PMU data. To mitigate the risk of cyber attacks, this thesis proposes a new protection strategy, which intends to mitigate the most damaging effect of LR attacks on power system operation. The objective is to mitigate the damage effects of false data injection attacks by increasing the attacking cost of an attacker. This is achieved by protecting a small set of critical measurements. To further reduce the computation complexity, we also propose a mixed integer linear programming approach to separate the power grid into several subnetworks, then distributed protection strategy is applied to each subnetwork. The results of this thesis reveal the mechanism of local false data injection attacks and highlight the importance and complexity of defending power systems against false data injection attacks.
Ph.D. in Electrical and Computer Engineering, July 2015
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Title: TEMPORAL AND SPATIOTEMPORAL MODELS FOR SHORT-CRIME PREDICTION
Creator: Liu, Xiaomu
Date: 2017, 2017-07
Description: One of the most important aspects of predictive policing is identifying the likely time and place of crime occurrences so as to prevent future...
Show moreOne of the most important aspects of predictive policing is identifying the likely time and place of crime occurrences so as to prevent future crimes. The ability to make short-term predictions may be of particular importance for optimizing police resource allocation. The goal of this study is to investigate the temporal and spatiotemporal pattern of crime in the city of Chicago and to build corresponding predictive models. First, a temporal model for forecasting citywide violent crime time count is proposed. This model is composed of a long-term trend and short-term variations using data of time, weather and crime. The importance of model reproducibility is addressed in this study to produce low-complexity models. We introduce an approach that provides a way to extend the model selection criterion to both prediction accuracy and model reproducibility. The experimental results show that models produced by this approach outperform several simple time-series models. It is also found that these models typically include fewer variables; therefore, they are more interpretable, and may provide superior generalization error. Next we develop a framework that provides predictions for tomorrow’s violent crime counts at the level of a police district. The procedures include citywide daily violent crime count prediction, violent crime density estimation, and distributing citywide predictions to districts according to the estimated densities. In order to estimate the crime spatial densities, we use mesh modeling and demonstrate that a mesh model can be used as the structure for modeling the spatial variation of crime rate since it is well adapted to the inhomogeneous crime distribution. The experimental results show that our method provides more-accurate forecasts than those given by historical crime statistics. One aspect of studying spatial pattern of crimes is identifying geographical regions with similar crime characteristics. Specifically, we illustrate applying unsupervised clustering techniques to segment the city into sub-regions. We explore the use of Gaussian mixture models combined with a Markov random field for the purpose of regularization. We also propose a framework for the evaluation of clustering models without knowing the ground truth, which can present a more-complete picture for model selection in unsupervised clustering problems. Finally, we develop a spatiotemporal prediction method that predicts the locations where violent crimes or property crimes are most likely to occur tomorrow. Crime incidents are rasterized by a spatiotemporal grid. Other factors that affect the time and location preferences of criminal activities are also leveraged and represented by that grid. Each spatiotemporal grid cell is treated as an example for training and testing our models. We also explore whether pooling data from various sub-regions based on spatial clustering can improve model performance. The experimental results show that our models are more accurate than conventional hot-spot models. It is found that the effects of using different training samples are not consistent, which depends on target crime type.
Ph.D. in Electrical Engineering, July 2017
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Title: CROSS-ETHNIC VARIATION IN THE RELATION BETWEEN PARENT AND CHILD BEHAVIORS AND YOUNG CHILDREN’S ACADEMIC AND SOCIAL FUNCTIONING
Creator: Bae, Hyo
Date: 2011-04-20, 2011-05
Description: The aim of this study was to determine if there is cross-ethnic variation in the relationships between parent behaviors, child behaviors, and...
Show moreThe aim of this study was to determine if there is cross-ethnic variation in the relationships between parent behaviors, child behaviors, and young children’s academic and social functioning. Participants included 96 African American, 117 Hispanic, and 395 White 5-year-old children and their parents. Self-reported parenting (Support/Engagement and Hostility/Coercion) was assessed with the Parent Behavior Inventory. Observed parent (Scaffolding) and child behaviors (Engagement/Persistence) were assessed using the Three Boxes Task videotaped parent-child interaction paradigm. Children’s academic skills were measured with three subtests of the Woodcock-Johnson Tests of Achievement-3rd Edition (Letter-Word Identification, Passage Comprehension, and Quantitative Concepts), and their social skills were measured with the Social Skills Rating System. Results of moderated regression analyses indicated that there were no direct effects of parenting on academic achievement, but that child Engagement/Persistence was related to academic achievement. With regard to social skills, Support/Engagement was related to Cooperation, Assertion, Responsibility, and Self-Control, while Hostility/Coercion was related to Cooperation, Responsibility, and Self-Control. Scaffolding was not directly related to social skills. Also, these analyses showed that the majority of these relationships were invariant across ethnic groups, with only a few significant interaction effects. Specifically, higher levels of Scaffolding were related to higher reading scores for African American children, while Scaffolding was not related to reading for White children. Although higher levels of Hostility/Coercion were related to lower reading scores for White children, this relationship was not significant for Hispanic children. Higher levels of Scaffolding were related to higher math scores for African American children. For White children, however, higher levels of Scaffolding were related to lower math scores. There were no ethnic differences in the relation between parent and child behaviors and social skills. Finally, results indicated that Scaffolding was indirectly related to academic and social functioning through Engagement/Persistence, and there was no ethnic variation in these relationships across African American, Hispanic, and White children. The implications of these findings and future directions for research are discussed.
Ph.D. in Psychology, May 2011.
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Title: ALTERNATIVE APPROACH TO VOLATILITY FORECASTING AND EVALUATING FORECASTING PERFORMANCE
Creator: Lim, Hyungjin
Date: 2012-10-08, 2012-12
Description: Studies in the volatility process of financial markets have focused more on volatility modeling aspects, using parametric assumptions....
Show moreStudies in the volatility process of financial markets have focused more on volatility modeling aspects, using parametric assumptions. Compared with the vast amount of research in parametric modeling, there is a lack of studies in nonparametric approaches in volatility forecasting and forecasting performance evaluation. This research intends to explore alternative approaches to forecasting volatility of financial returns, and evaluation of forecasting models. This research will employ grammatical evolution to propose a hybrid forecasting model that utilizes the benefits of parametric and genetic programming models. Furthermore, an alternative methodology to handle structural breaks in volatility is examined by utilizing an adaptive approach in dynamic environments. In an extensive empirical study, the proposed models will be compared with the other models widely used in the literature using statistical and economic tests. Specifically, as an alternative to the statistical performance evaluation measure, a nontraditional method derived from the idea of speculating on asset volatility will be employed to compare the performance as well as to assess economic usefulness of competing volatility models. The hybrid model provided superior forecasting performance than traditional techniques both on economic and statistical measures.
PH.D in Management Science, December 2012
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Title: THEORETICAL ANALYSIS OF REAL-TIME SCHEDULING ON RESOURCES WITH PERFORMANCE DEGRADATION AND PERIODIC REJUVENATION
Creator: Hua, Xiayu
Date: 2017, 2017-07
Description: In 1973, Liu and Layland [81] published their seminal paper on schedulability analysis of real-time system for both EDF and RM schedulers. In...
Show moreIn 1973, Liu and Layland [81] published their seminal paper on schedulability analysis of real-time system for both EDF and RM schedulers. In this work, they provide schedulability conditions and schedulability utilization bounds for both EDF and RM scheduling algorithms, respectively. In the following four decades, scheduling algorithms, utilization bounds and schedulability analyses for real-time tasks have been studied intensively. Amongst those studies, most of the research rely on a strong assumption that the performance of a computing resource does not change during its lifetime. Unfortunately, for many long standing real-time systems, such as data acquisition systems (DAQ) [74, 99], deep-space exploration programs [120, 119] and SCADA systems for power, water and other national infrastructures [121, 26], the performance of computational resources suffer notably performance degradations after a long and continuous execution period [61]. To overcome the performance degradation in long standing systems, countermeasures, which are also called system rejuvenation approaches in the literature [123, 61, 126], were introduced and studied in depth in the last two decades. Rejuvenation approaches recover system performance when being invoked and hence benefit most long standing applications [30, 102, 11, 12, 39]. However, for applications with real-time requirements, the system downtime caused by rejuvenation process, along with the decreasing performance during the system’s available time, makes the existing real-time scheduling theories difficult to be applied directly. To address this problem, this thesis studies the schedulability issues of a realtime task set running on long standing computing systems that suffers performance degradation and uses rejuvenation mechanism to recover. Our first study in the thesis focus on a simpler resource model, i.e. the periodic resource model, which only considers periodic rejuvenations. We introduce a method, i.e., Periodic Resource Integration, to combine multiple periodic resources into a single equivalent periodic resource and provide the schedulability analysis based on the combined periodic resource for real-time tasks. By integrating multiple periodic resources into one, existing real-time scheduling researches on single periodic resource can be directly applied on multiple periodic resources. In our second study, we extend the periodic resource mode to a new resource model, the P2-resource model, in our second work to characterize resources with both the performance degradation and the periodic rejuvenation. We formally define the P2-resource and analyze the schedulability of real-time task sets on a P2-resource. In particular, we first analyze the resource supply status of a given P2-resource and provide its supply bound and linear supply bound functions. We then developed the schedulability conditions for a task set running on a P2-resource with EDF or RM scheduling algorithms, respectively. We further derive utilization bounds of both EDF and RM scheduling algorithms, respectively, for schedulability test purposes. With the P2-resource model and the schedulability analysis on a single P2- resource, we further extend our work to multiple P2-resources. In this research, we 1) analyze the schedulability of a real-time task set on multiple P2-resources under fixedpriority scheduling algorithm, 2) introduce the GP-RM-P2 algorithm and 3) provide the utilization bound for this algorithm. Simulation results show that in most cases, the sufficient bounds we provide are tight. As the rejuvenation technology keeps advancing, many systems are now able to perform rejuvenations in different system layers. To accommodate this new advances, we study the schedulability conditions of a real-time task set on a single P2-resource with both cold or warm rejuvenations. We introduce a new resource model, the P2-resource with duel-level rejuvenation, i.e., P2D-resource, to accommodate this new feature. We first study the supply bound and the linear supply bound of a given P2D-resource. We then study the sufficient utilization bounds for both RM and EDF scheduling algorithms, respectively.
Ph.D. in Computer Science, July 2017
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Title: CONTRIBUTIONS TO ALGORITHMIC MATROID PROBLEMS
Creator: Huang, Jinyu
Date: 2015, 2015-07
Description: In this thesis, we obtain several algorithms for problems related to matroids, a structure that generalizes the concept of linear independence...
Show moreIn this thesis, we obtain several algorithms for problems related to matroids, a structure that generalizes the concept of linear independence in a vector space and an acyclic subgraph structure in a graph. Matroids have been widely applied in combinatorial optimization, graph theory, coding theory and so forth. Specifically, our results include: In this thesis, we present a constant-competitive online algorithm of the matroid secretary problem for the partition matroids without information of the partition and for the paving matroids. We also introduce the multi-objective matroid secretary problem that extends the matroid secretary problem, in which the weight function is a k-vector w = [w1, · · · , wk]. We show a constant competitive algorithm of the multiobjective matroid secretary problem for the uniform matroids and for the paving matroids. Since bases of a matroid generalize many important combinatorial structures, many counting problems can be expressed as a problem that counts the number of bases of a matroid. An efficient approximate counting algorithm can be designed provided that a rapidly-mixing Markov chain that samples bases of a matroid can be constructed. Let Φ(G) be the conductance of the base-exchange graph G. Matroid- Expansion Conjecture (1989, Mihai and Vazirani) states that Φ(G) ≥ 1 for any base-exchange graph G of a matroid, which implies an FPRAS (fully-polynomial randomized approximation scheme) for counting the number of bases of a matroid. We use λ2, the second smallest eigenvalue of L, the discrete Laplacian matrix of G, to prove the Matroid-Expansion Conjecture for any paving matroid, for any balanced matroid, and for the direct sum of a paving matroid with a balanced matroid. A maximum linear matroid parity set is called a basic matroid parity set, if its size is the rank of the matroid. We show that determining the existence of a common base (basic matroid parity set) for linear matroid intersection (linear matroid parity) is in NC2, provided that there are polynomial number of common bases (basic matroid parity sets). For graphic matroids, we show that finding a common base for matroid intersection is in NC2, if the number of common bases is polynomial bounded. We also give a new RNC2 algorithm that finds a common base for graphic matroid intersection. Finally, we prove that if there is a black-box NC algorithm for PIT (Polynomial Identity Testing), then there is an NC algorithm to determine the existence of a common base (basic matroid parity set) for linear matroid intersection (linear matroid parity).
Ph.D. in Applied Mathematics, July 2015
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