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Title: SHIPPING CONTAINER AS HOME FOR MIGRANT WORKER IN CHINA
Creator: Yang, Ying
Date: 2014, 2014-12
Description: The spectacular increasing population of Chinese rural migrant workers is a big issue faced by government in recent years. Most of Chinese...
Show moreThe spectacular increasing population of Chinese rural migrant workers is a big issue faced by government in recent years. Most of Chinese migrant workers are now confronted with the difficult working and living conditions in the Chinese labor market. How to relieve the tension of housing market for these poverty migrant workers is the question of my thesis. To satisfy worker’s desire for basic living conditions, a modular housing service system in China is a practicable infrastructural project to be developed by government.
M.S. in Architecture, December 2014
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Title: POWER OPTIMIZATION IN DEEP SUBMICRON VLSI CIRCUITS: FROM SYSTEM LEVEL TO CIRCUIT LEVEL
Creator: Tong, Qiang
Date: 2017, 2017-07
Description: As VLSI technology advances to deep sub-micron regime, power consumption has become a critical concern in VLSI circuits. Therefore, power...
Show moreAs VLSI technology advances to deep sub-micron regime, power consumption has become a critical concern in VLSI circuits. Therefore, power optimization becomes mandatory in VLSI design nowadays. To reduce the power consumption, many techniques have been proposed at various levels of VLSI circuits design: system level, register-transfer level(RTL), and circuit/transistor level. This dissertation starts with a review of system level power optimization techniques. Experiments on a computer architecture simulation system have been conducted to compare the impact of different programming styles at system level on power consumption. The results could be used as an intuitive guidance for programmers with intention for implementing power-aware system. The second topic in this dissertation is a clustering based clock gating technique, targeting power reduction at RT-Level. Clock gating is an effective and popular method to reduce dynamic power in VLSI circuits, it can be applied at both RT-level and gate level. The basic idea of clock gating is to disable the clock of one or more sequential logics (majorly flip-flops) when the input data of the logic cells do not change. In this dissertation, a clustering based clock gating technique is proposed, the technique exploits activity information of each flip-flop, and clusters them into groups according to their activity correlations. As the leakage power has become a major concern in VLSI design, the proposed As the leakage power has become a major concern in VLSI design, the proposed clustering method is extended down to gate level and a clustering based hybrid clock gating and power gating technique is proposed. The technique can reduce both the dynamic power and leakage power in VLSI circuits. As process technology scaling down to deep submicron regime, bulk CMOS technology has encountered many challenges due to short channel effect (SCE), which degrades the reliability and feasibility of MOSFET devices. New technologies such as FinFET and carbon nanotube FET (CNFET) are two promising substitute solutions in the following decade to address SCE issue. Part of this dissertation presents circuit design using these new process technologies for low power VLSI circuits. More specifically, two SRAM cell designs using FinFET and CNFET devices are proposed. The new designs can improve performance while reduce power consumption.
Ph.D. in Electrical Engineering, July 2017
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Title: ULTRALOW POWER SRAM DESIGN IN NEAR THRESHOLD REGION USING 45NM CMOS TECHNOLOGY
Creator: Chen, Yinhui
Date: 2011-05-10, 2011-05
Description: With the development of CMOS technology, the performance including power dissipation and operation speed is highly concerned for SRAM design....
Show moreWith the development of CMOS technology, the performance including power dissipation and operation speed is highly concerned for SRAM design. Desirable low power consumption while operating fast is the goal of design and improvement. However, the tradeoff between performance and speed is one of the most challenging obstacles that engineers are facing. Along with continuously scaling in the process technology, the concern for stability of Static Random Access Memories (SRAMs) is increasing in the design and test. Maintaining an acceptable Static Noise Margin (SNM) as well as scaling the minimum feature sizes and supply voltages of the Systems-on-a-Chip (SoC) becomes more and more challenging. Subthreshold leakage, dynamic power consumption and delay are major issues for circuits design, especially for SRAM design. Subthreshold leakage and dynamic power consumption can be decreased while supply voltage is scaled down. However, this may dramatically increase the circuit delay (Lindert, 1999) (Wang, 2004) (Zhai, 2004). In this dissertation, we first prepared fundamental knowledge of the CMOS technology as well as SRAM. According to the current researches on SRAM (Chang, 2005) (Chen, 2010), we proposed a novel 6t SRAM design which operates in near threshold region to optimize leakage power and speed. Negative word line is introduced to reduce the leakage current. A novel Latch-type voltage sense amplifier is proposed to improve the read speed of the proposed SRAM cell. The proposed SRAM design is implemented in 45nm technology and achieves more than 50% for power reduction, 68% for leakage reduction, 90% for write delay reduction and 78% for read delay reduction compared to traditional 6T SRAM in near threshold region. Although the proposed 6T SRAM inherit the disadvantage of 4T schematic in data retention, the operation stability is still respectable.
M.S. in Electrical Engineering, May 2011
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Title: INFORMATION PROPAGATION DYNAMIC THROUGH VEHICLE TO VEHICLE COMMUNICATION NETWORK ON A ROAD SEGMENT
Creator: Wang, Lu
Date: 2015, 2015-12
Description: Vehicle-to-vehicle communication system enables vehicles to share various traffic information such as road surface condition, real-time...
Show moreVehicle-to-vehicle communication system enables vehicles to share various traffic information such as road surface condition, real-time traffic congestion, crashing alert or weather situation. Thus, it has a great potential to improve traffic safety, mobility and environmental sustainability. To grant this great promise, information availability plays a critical roles. Accordingly, many previous studies have investigated statistic characteristics (such as mean and variance) of information propagation (such as speed/time delay via instantaneous transmission, connectivity, etc.) integrating traffic flow features. However, few of them are able to capture the information spread dynamics based on V2V. Motivated by this view, this research seeks to develop a discrete mathematical approach to capture information coverage dynamics built upon traffic flow dynamics, which is described by discrete traffic flow dynamics, i.e., cell transmission model. The approach is entailed by developed mathematical model to capture inner-cell information propagation delay and inter-cell transmission based on the proposed information-traffic cell transmission model. The development of the proposed methodology considers a single or two piece(s) of information is (are) sequentially landed on a one-way or two-way road segment underVehicle-to-vehicle communication system enables vehicles to share various traffic information such as road surface condition, real-time traffic congestion, crashing alert or weather situation. Thus, it has a great potential to improve traffic safety, mobility and environmental sustainability. To grant this great promise, information availability plays a critical roles. Accordingly, many previous studies have investigated statistic characteristics (such as mean and variance) of information propagation (such as speed/time delay via instantaneous transmission, connectivity, etc.) integrating traffic flow features. However, few of them are able to capture the information spread dynamics based on V2V. Motivated by this view, this research seeks to develop a discrete mathematical approach to capture information coverage dynamics built upon traffic flow dynamics, which is described by discrete traffic flow dynamics, i.e., cell transmission model. The approach is entailed by developed mathematical model to capture inner-cell information propagation delay and inter-cell transmission based on the proposed information-traffic cell transmission model. The development of the proposed methodology considers a single or two piece(s) of information is (are) sequentially landed on a one-way or two-way road segment under sparse or congested traffic flow considered. Next-Generation simulation field data and Paramics simulated data are used to verify the accuracy of the experiments. Our experimental results show that the proposed model can accurately track information spread dynamics with mean absolute error less than 5% over all experiments. Key words: Vehicle-to-vehicle communication system; cell transmission model; time delay; information propagation coverage.
M.S. in Civil Engineering, December 2015
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Title: Quantitative Tools for Stochastic Dynamical Systems: Invariant Structures and Escape Probabilities
Creator: Kan, Xingye
Date: 2012-07-16, 2012-07
Description: Three types of quantitative structures, stochastic inertial manifolds, random invariant foliations, and escape probabilities, are investigated...
Show moreThree types of quantitative structures, stochastic inertial manifolds, random invariant foliations, and escape probabilities, are investigated to study stochastic dynamical systems. Invariant structures for stochastic dynamical systems are reviewed and detailed techniques for their simulation, approximation and construction are presented with several illustrative examples. First, a numerical approach for the simulation of inertial manifolds of stochastic evolutionary equations with multiplicative noise is presented and illustrated. After splitting the stochastic evolutionary equations into a backward and a forward part, a numerical scheme is devised for solving this backward-forward stochastic system, and an ensemble of graphs representing the inertial manifold is consequently obtained. This numerical approach is tested in two illustrative examples: one is for a stochastic differential equation and the other is for a stochastic partial differential equation. Second, invariant foliations for dynamical systems with small white noisy perturbation are approximated via asymptotic analysis. In other words, random invariant foliations are represented as a perturbation of the corresponding deterministic invariant foliations, with deviation errors estimated. The escape probability is a deterministic concept making methods of partial differential equations theory attainable to stochastic dynamics. Finally, the escape probability p(x) for dynamical systems driven by non-Gaussian L´evy motions, especially symmetric α-stable L´evy motions, is considered and characterized. More precisely, it is represented as the solution of the Balayage-Dirichlet problem of a certain partial differential-integral equation. This issue has been investigated previously for dynamical systems driven by Wiener process. Differences between escape probabilities for dynamical systems driven by Gaussian and non-Gaussian noises are highlighted.
Ph.D. in Applied Mathematics, July 2012
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Title: MODELLING INTERACTION BETWEEN CD8+ T CELLS AND BETA CELLS IN PATHOGENESIS OF TYPE 1 DIABETES
Creator: Xu, Qian
Date: 2016, 2016-12
Description: Diabetes is one of the prevalent diseases in the USA, which affects the lives of millions of people. In 2010 only, there was a total of 234...
Show moreDiabetes is one of the prevalent diseases in the USA, which affects the lives of millions of people. In 2010 only, there was a total of 234,051 deaths linked to diabetes in the USA. Research related to preclinical and clinical assays are always costly and time consuming. Modeling is a helpful method to reduce the cost of clinical experiments and accelerates the discovery and improvement of new therapies. This research is focused on the development of a high performance agent-based model simulating the pathogenesis of Type 1 diabetes mellitus in pancreas. The whole immune response takes place in three compartments, pancreatic lymph node, circulation, and pancreas. A significant part of the complex interactions leading to Type 1 diabetes takes place in the pancreatic tissue. Therefore, the focus was placed on the islets of Langerhans in the pancreas, and the interaction of CD8+ T cells and Beta cells were modeled. T cell behavior was incorporated as rules in this model such as activation, migration, proliferation, apoptosis, and cytotoxicity. Likewise Beta cell death and regeneration under the T cell attack were modeled. The model is able to capture the trends of T cell and Beta cell variations during the disease progression and portrays the role of CD8+ T cells in the process. It is expected that, with the addition of other immune system and pancreatic tissue components, the model will be a valuable tool for the planning of clinical studies.
M.S. in Biomedical Engineering, December 2016
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Title: A MULTI-CURVE LIBOR MARKET MODEL WITH UNCERTAINTIES DESCRIBED BY RANDOM FIELDS
Creator: Xu, Shengqiang
Date: 2012-12-19, 2012-12
Description: The LIBOR (London Interbank Offered Rate) market model has been widely used as an industry standard model for interest rates modeling and...
Show moreThe LIBOR (London Interbank Offered Rate) market model has been widely used as an industry standard model for interest rates modeling and interest rate derivatives pricing. In this thesis, a multi-curve LIBOR market model, with uncertainty described by random fields, is proposed and investigated. This new model is thus called a multi-curve random fields LIBOR market model (MRFLMM). First, the LIBOR market model is reviewed and the closed-form formulas for pricing caplets and swaptions are provided. It is extended to the case when the uncertainty terms are modeled as random fields and consequently the closed-form formulas for pricing caplets and swaptions are derived. This is a new model called the random fields LIBOR market model (RFLMM). Second, local volatility models and stochastic volatility models are combined with the RFLMM to explain the volatility skews or smiles observed in market. Closedform volatility formulas are derived via the lognormal mixture model in local volatility case, while the approximation scheme for the stochastic volatility case is obtained by a stochastic Taylor expansion method. Moreover, the above work is further extended to a multi-curve framework, where the curves for generating future forward rates and the curve for discounting cash flows are modeled distinctly but jointly. This multi-curve methodology is recently introduced lately by some pioneers to explain the inconsistency of interest rates after the 2008 credit crunch. Both LIBOR market model and RFLMM mentioned above can be categorized as models in singe-curve framework. Third, analogous to the single-curve framework, the multi-curve random fields LIBOR market model is derived and caplets and swaptions are priced with closedform formulas that can be reduced to exactly the Black’s formulas. This model is called a multi-curve random fields LIBOR market model (MRFLMM). Meanwhile, xii local volatility and stochastic volatility models are also combined with the multi-curve LIBOR market model to explain the volatility skews and smiles in the market. Fourth, the calibration of the above models is considered. Taking two-curve setting as an example, four different models, single-curve LIBOR market model, single-curve RFLMM, two-curve LIBOR market model and two-curve RFLMM are compared. The calibration is based on the spot market data on one trading day. The four models are calibrated to European cap volatility surface and swaption volatilities, given the specified parameterized form of correlation and instantaneous volatility. The calibration results show that the random fields models capture the volatility smiles better than non-random fields models and has less pricing error. Moreover, multi-curve models perform better than single-curve models, especially during/after credit crunch. Finally, the estimation of these four models, including pricing and hedging performance, is considered. The estimation uses time series of forward rates in market. Given a time series of term structure, the parameters of the four models are estimated using unscented Kalman filter (UKF). The results show that the random fields models have better estimation results than non-random fields models, with more accurate in-sample and out-sample pricing and better hedging performance. The multi-curve models also over-perform the single-curve models. In addition, it is shown theoretically and empirically that the random fields models have advantages that it is unnecessary to determine the number of factors in advance and not needed to re-calibrate. The multi-curve random fields LIBOR market model has the advantages of both multi-curve framework and random fields setting.
PH.D in Applied Mathematics, December 2012
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Title: DEVELOPMENT AND ANALYSIS OF A SECURE AND EFFICIENT VEHICULAR AD HOC NETWORK
Creator: Hao, Yong
Date: 2012-07-06, 2012-07
Description: Vehicular ad hoc networks (VANETs) enable vehicles to communicate with each other by equipping every vehicle with an on board unit (OBU). Many...
Show moreVehicular ad hoc networks (VANETs) enable vehicles to communicate with each other by equipping every vehicle with an on board unit (OBU). Many interesting and promising functionalities can be achieved in the VANETs, such as safety related application and data downloading application. In this thesis, we focus on the security and privacy provision as well as efficiency improvement of above two applications in the VANETs. In the safety related application, each vehicle periodically broadcasts messages including its current position, direction and velocity (which can be generated by a global positioning system (GPS) device) to inform its geographic data to its neighbors. Privacy is an important issue in VANETs. Meanwhile, some important security functionalities such as message authentication, integrity and non-repudiation should be integrated into the VANETs. In this thesis, we propose a distributed key management protocol based on group signature to provide security and privacy for vehicles. Distributed key management is expected to facilitate the revocation of malicious vehicles, verification efficiency, maintenance of the system and heterogeneous security policies, compared with the centralized key management assumed by the existing group signature schemes. In our framework, each road side unit (RSU) acts as the key distributor for the group, where a new issue incurred is that the semi-trust RSUs may be compromised. Therefore, we develop security protocols which are able to detect compromised RSUs and their malicious accomplices. Moreover, we address the issue of large computation overhead due to the group signature implementation. A practical cooperative message authentication protocol (CMAP) is thus proposed to alleviate the verification burden for vehicles. In the CMAP, on average, each vehicle just needs to verify a very small amount of received geographic messages. Compared with the existing probabilistic verification protocol, CMAP can save at least 40 % computation resource for vehicles. In the data downloading application, we propose a secure cooperative data downx loading framework for payment services in VANETs. In our framework, vehicles download data when they pass by an RSU and then share the data after they travel out of the RSU’s coverage. A fundamental issue of our framework is how vehicles share data with each other. Thus, we develop an application layer data sharing protocol (DSP) in which vehicles share their downloaded data one by one in sequence according to their positions. A better performance can be achieved by the proposed protocol because it is able to avoid medium access control (MAC) layer collisions and the hidden terminal effect. Analytical models are derived to quantitatively evaluate the impact of the distance between RSUs on the amount of data that vehicles can download in a drive through. The simulation results show that our protocol can download 87.4% more data for vehicles than the existing scheme “VC-MAC” when the distance between two consecutive RSUs reaches 10 kilometers. Moreover, we also address security and privacy issues in the process of data downloading and sharing. Both applicants’ exclusive access to the applied data and vehicles’ privacy are ensured by our framework. Compared with the communication overhead in the intuitive method, the communication overhead in our framework will be reduced to 50%. We also propose a security protocol to detect sybil attacks in privacy preserved VANETs. In the above two applications, vehicles’ location information is utilized to facilitate the efficiency. However, if malicious vehicles launch the sybil attack by forging several fake entities and claim they are at some certain positions. The overall performance of the applications will be compromised greatly. So, we propose a security protocol to detect sybil attacks by examining the rationality of vehicles’ positions. The attack detection utilizes the characteristics of communication. No extra hardware and little communication and computation overhead will be introduced to vehicles. Moreover, a smart attacker scenario in which a malicious vehicle may adjust its communication range to avoid detection and the malicious vehicles’ collusion scenario are also considered.
Ph.D. in Computer Engineering, July 2012
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Title: DYNAMIC COHERENT ACCEPTABILITY INDICES AND THEIR APPLICATIONS IN FINANCE
Creator: Zhang, Zhao
Date: 2011-05-02, 2011-05
Description: This thesis presents a unified framework for studying coherent acceptability indices in a dynamic setup. We study dynamic coherent...
Show moreThis thesis presents a unified framework for studying coherent acceptability indices in a dynamic setup. We study dynamic coherent acceptability indices and dynamic coherent risk measures. In particular, we establish a duality between them. We derive representation theorems for both dynamic coherent acceptability indices and dynamic coherent risk measures in terms of so called dynamically consistent sequence of sets of probability measures. In addition, we present an alternative approach to study dynamic coherent acceptability indices and the representation theorem. Finally, we provide examples and counterexamples of dynamic coherent acceptability indices, and their applications in portfolio management.
Ph.D. in Applied Mathematics, May 2011
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Title: DEVELOPMENT OF A PROGRAMMABLE WIRELESS NETWORK TEST BED OVER ANDROID SMARTPHONE
Creator: Zhou, Chenyang
Date: 2016, 2016-05
Description: As wireless applications are increasingly prevalent in recent years, smartphones, the link between wireless world and common life, become more...
Show moreAs wireless applications are increasingly prevalent in recent years, smartphones, the link between wireless world and common life, become more and more indispensable. Subsequently, smartphone applets become more and more complicated, protocols like 3G,LTE,4G have also been improved to satisfy people’s increasing requirement. This leads to an exponentially increase in energy consumption. However, the power of smartphone battery is limited, and thus how to improve energy efficiency and extend the life-time of smartphone battery becomes a critical issue. In wireless local area networks (WLANs), switching to low-power sleep mode to save energy is common. Power-Saving mode (PSM) was one of the standard algorithm in order to save energy. This feature allows devices to switch the WiFi on and off several times a second. However, research papers have shown that PSM is not really efficient in practice, and in many cases (e.g. multiple stations), can actually degrade performance. This sleep-scheduling algorithm, derived from GreenCall Algorithm is demonstrated to have lower packets loss rate while achieving higher energy efficiency than that of the existing GreenCall Algorithm.
M.S. in Electrical Engineering, May 2016
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Title: CONTROLLER DESIGN AND DISTRIBUTED CONTROL WITHIN MULTI-AGENT SYSTEMS
Creator: Shao, Quan Min
Date: 2013, 2013-12
Description: None
PH.D in Chemical and Biological Engineering, December 2013

Title: INTERACTION IN THE SIXTH SENSE
Creator: Ghods, Ramin
Date: 2014, 2014-05
Description: Every experience of architecture is rooted in multi-sensory and embodied interactions with surroundings. All sensory modalities as well as...
Show moreEvery experience of architecture is rooted in multi-sensory and embodied interactions with surroundings. All sensory modalities as well as linguistic paradigms are integrated in the sensorimotor cortex of brain where mirror neurons are originated therein. Neurological understanding, on the other hand, suggests that meaning is always contextually grounded. Metaphor, in its very essence, is an expression to convey meaning to spectator. It stimulates ventra premotor cortex of brain, wherein mirror neurons activate the embodied simulation of actions, emotions, and corporeal sensations. So conceptual metaphors in everyday language are highly based on bodily interaction and encountering with surroundings. Additionally, they are also rooted in context and primordial images. Metaphor creates an interactive atmosphere in which symbolic and literal meanings are conveyed to beholders. Atmosphere is the essence of a space, in other words, understanding this atmosphere is the most crucial for understanding architecture. Spatial experiencing in its complete entirely could be taken through the emissions of atmosphere. In general, interaction in the 6th sense is focusing on a methodology of design to facilitate immediate perception of spatial settings of architecture. Far from abstraction and intellectualism, an atmosphere conveyed meaning through sensual perceptions. In this case, several modalities of architectural design, including materializes and de-materialized qualities such as light, texture, geometry, reflection, smell, sound, air, have been identified as contributing to atmosphere.
M.S. in in Architecture, May 2014
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Title: HIGH PERFORMANCE AND LOW POWER HARDWARE IMPLEMENTATION FOR CRYPTOGRAPHIC HASH FUNCTIONS
Creator: Zhang, Yunlong
Date: 2013-04-30, 2013-05
Description: In this thesis, we introduce hash encryption functions which are widely used in a number of protocols as digital signature to protect privacy...
Show moreIn this thesis, we introduce hash encryption functions which are widely used in a number of protocols as digital signature to protect privacy information. Since the hash algorithm can be speeded up and be more security by physical protection, hash function hardware implementation is more desired today for evaluating its performance and processing data with dramatically increased size. Then we consider those two problems in the hash function hardware implementation: throughput and power consumption. High level of throughput is significant for the efficiency of hash algorithm. By using unfolding transformation, the throughput of hash function can be increased apparently. However, power consumption, area and critical path delay will also be increased. Pipeline and parallelism is an effective technique to decrease the critical path delay, by analyzing the construction of computing process. Another Problem is power consumption which will influence the reliability and cost of device. Clock gating is a widely used and efficiency technique for dynamic power reducing at register transfer level (RTL). There are two basic modes for single level clock gating: XOR-based clock gating and load-enable based clock gating [13]. The former one is based on the comparing between output and input of flip-flops (FFs). Although this XOR-based clock gating technique is not used in our hash function hardware implementation, we will briefly introduce some techniques of this method which is our previous research work for dynamic power reduction by comparing some RTL low power techniques. x Next, load-enable based clock gating which works with an enable signal is introduced. According to the idle mode of some components in our simply hash encryption system, we use this load-enable based clock gating to eliminate wasted toggle rate of some signals, thus reducing dynamic power consumption. Finally, according to the source of dynamic power dissipation, reducing clock frequency is another choice. Frequency trade-off technique is proposed, which combines unrolling transformation with frequency scaling. In this technique, a scope of frequency value is given in each hash function with different number of iteration rounds for trading off low dynamic power consumption and high throughput.
M.S. in Electrical Engineering, May 2013
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Title: NON-GAUSSIAN STOCHASTIC DYNAMICS: MODELING, SIMULATION, QUANTIFICATION AND ASSIMILATION
Creator: Gao, Ting
Date: 2015, 2015-05
Description: Motivated by real world applications, three topics - deterministic quantities, uncertainty quantification and data assimilation, are...
Show moreMotivated by real world applications, three topics - deterministic quantities, uncertainty quantification and data assimilation, are considered for non-Gaussian stochastic dynamics. More specifically, three problems are formulated to investigate non-Gaussian dynamics: (i) exit problem and time-dependent probability density; (ii) parameter and function estimation for stochastic differential equations driven by L´evy motion; and (iii) nonlinear data assimilation to infer transition phenomena. First, numerical algorithms are developed to study important metrics: mean exit time, escape probability and time-dependent probability density, which can be utilized to quantify dynamical behaviors of stochastic differential equations with non- Gaussian -stable L´evy motion. Moreover, detailed numerical analysis work is done to ensure the algorithms accurate, fast and stable considering the singular nature of the L´evy jump measure. Second, new approaches on parameter and function estimation in stochastic dynamical systems are devised. Taking advantage of observations on mean exit time, escape probability or probability density, model uncertainty can be quantified by some optimization methods. These methods are beneficial to systems for which mean exit time, escape probability or probability density are feasible to observe. Finally, nonlinear data assimilation on non-Gaussian models is studied. For continuous-discrete filtering, a recursive Bayesian approach is used, and for continuous filtering, Zakai equation is solved to provide the system state estimation. In both cases, time-dependent transition probability between metastable states are investigated. xiMotivated by real world applications, three topics - deterministic quantities, uncertainty quantification and data assimilation, are considered for non-Gaussian stochastic dynamics. More specifically, three problems are formulated to investigate non-Gaussian dynamics: (i) exit problem and time-dependent probability density; (ii) parameter and function estimation for stochastic differential equations driven by L´evy motion; and (iii) nonlinear data assimilation to infer transition phenomena. First, numerical algorithms are developed to study important metrics: mean exit time, escape probability and time-dependent probability density, which can be utilized to quantify dynamical behaviors of stochastic differential equations with non- Gaussian -stable L´evy motion. Moreover, detailed numerical analysis work is done to ensure the algorithms accurate, fast and stable considering the singular nature of the L´evy jump measure. Second, new approaches on parameter and function estimation in stochastic dynamical systems are devised. Taking advantage of observations on mean exit time, escape probability or probability density, model uncertainty can be quantified by some optimization methods. These methods are beneficial to systems for which mean exit time, escape probability or probability density are feasible to observe. Finally, nonlinear data assimilation on non-Gaussian models is studied. For continuous-discrete filtering, a recursive Bayesian approach is used, and for continuous filtering, Zakai equation is solved to provide the system state estimation. In both cases, time-dependent transition probability between metastable states are investigated.
Ph.D. in Applied Mathematics, May 2015
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Title: ANTIBODY AND PEPTIDE CONJUGATES OF BIFUNCTIONAL CHELATORS FOR TARGETED CANCER THERAPY AND IMAGING
Creator: Kang, Chi Soo
Date: 2014, 2014-07
Description: A bifunctional ligand that can rapidly form a stable complex with a metal while conjugated to a tumor-targeting moiety is essential for...
Show moreA bifunctional ligand that can rapidly form a stable complex with a metal while conjugated to a tumor-targeting moiety is essential for targeted therapy and imaging of cancer. New bifunctional chelators in the NETA and DEPA series were developed for targeted radiation cancer therapy. The chelators showed rapid complexation kinetics with 90Y and 177Lu, and the corresponding radiolabeled complexes were stable in vitro and in vivo. Trastuzumab, Panitumumab, and c(RGDyK) conjugates (targeting HER-2, HER-1, and integrin αvβ3, respectively) of the novel bifunctional ligands were prepared. The conjugates displayed fast complexation kinetics with 90Y, 177Lu, and 205/6Bi, and the antibody and peptide conjugates labeled with 90Y, 177Lu, or 205/6Bi exhibited excellent stability and tumor targeting in mice bearing human colorectal cancer (LS-174T). Transferrin (Tf) and bile acid (BA) conjugates of novel chelators in the NE3TA series were prepared for targeted iron chelation therapy (ICT) and positron emission tomography (PET) imaging applications of cancer. Tf and BA conjugates of NE3TA had high cytotoxicity on HeLa, HT29, and PC3 cancer cells. The Tf-N-NE3TA and BA-N-NE3TA also displayed rapid complexation kinetics with 64Cu, and the Tf and BA conjugates of N-NE3TA labeled with 64Cu were stable and had high cellular uptake in HeLa and PC3 cancer cells. Tf-N-NE3TA was further conjugated with a fluorescence dye (Cy5.5) to develop targeted theranostic agent of cancer. Tf-N-NE3TA-Cy5.5 showed great radiolabeling efficiency with 64Cu, and the Tf-N-NE3TA-Cy5.5 labeled with 64Cu exhibited high cellular uptake in HeLa, HT29, and PC3 cancer cells. In summary, we have developed new bifunctional ligands having excellent chelation chemistry of 90Y, 177Lu, 205/6Bi, and 64Cu, and the tumor-specific antibody and peptide conjugates of the novel bifunctional chelators have a great potential for targeted cancer therapy and imaging as well as theranostic applications of cancer.
Ph.D. in Biology, July 2014
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Title: HYPOTHESIS TESTING FOR STOCHASTIC PDES DRIVEN BY ADDITIVE NOISE
Creator: Xu, Liaosha
Date: 2013, 2013-12
Description: We study hypothesis testing problem for the drift/viscosity coefficient for stochastic fractional heat equation driven by additive space-time...
Show moreWe study hypothesis testing problem for the drift/viscosity coefficient for stochastic fractional heat equation driven by additive space-time white noise colored in space. Since it is the first attempt to deal with hypothesis testing in SPDEs, we assume that the first N Fourier modes of the solution are observed continuously over time interval [0, T], similar methodology could be developed later for discrete sampling. The highlight of this article lies in the notion of “asymptotically the most powerful test” we introduce, which is a brand new idea for hypothesis testing not only in stochastic PDEs but in general stochastic processes. This conception provides a definite criterion how we compare the convergence rates of errors of two tests and how we maximize this convergence rate in a given rejection class when T or N is near infinity. And also we will give some equally important results for controlling the errors with finite T and N. We will build up asymptotic rejection class and find explicit forms of “the most powerful test” in two asymptotic regimes: large time asymptotics T →∞, and increasing number of Fourier modes N → ∞. The proposed statistics are derived based on Maximum Likelihood Ratio. We first consider a simple hypothesis testing, for which we exploit the key technic, by which we continue considering for more general issues. Over the course of proving the main results, we obtain a series of technical results on the asymptotic behaviors of the probabilities related to likelihood ratio, which are also, in some sense, of high value for study in probability theory. In particular, we find the cumulant generating function of the log-likelihood ratio, we obtain some sharp large deviation type results for both T → ∞ and N → ∞, and develop some useful strategies in probability convergence for studying asymptotic properties of the power of the likelihood ratio type tests.
M.S. in Applied Mathematics, December 2013
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Title: ANALYSIS AND PROTOTYPING OF ENERGY HARVESTING SYSTEM BASED ON DIELECTRIC ELECTRO ACTIVE POLYMER
Creator: He, Peiwen
Date: 2012-04-26, 2012-05
Description: Energy harvesting is a new emerging technology which is used to gather am- bient energy from all surroundings. Dielectric Electro Active...
Show moreEnergy harvesting is a new emerging technology which is used to gather am- bient energy from all surroundings. Dielectric Electro Active Polymer (DEAP) is a new material for energy harvesting based on mechanical-to-electric energy conversion. By using MATLAB simulation, a new system design based on DEAP is proposed to harvest energy. In the proposed system, the energy harvesting and the feedback cir- cuit loops can keep the system working without an external source. The simulation results show that the proposed system can harvest energy, and the bias voltage can be supplied by the system itself. Hence, no external source is needed. For circuit level design, based on two different vibration input patterns in terms of mechanical vibration frequency and displacement, two topologies of system forward paths which include DEAP generator, voltage regulation circuit and DC-DC buck converter are designed. For the low frequency high displacement vibration input pattern, a low frequency forward path is developed by using Zener diode regulator. For the high frequency low displacement input pattern, a high frequency forward path is designed by using Butterworth low pass filter. PSPICE simulation results prove that both of the proposed circuits work properly to generate steady DC voltage for energy harvesting. Finally, a prototyping circuit including a low pass filter and a battery charging module is implemented in experiment to verify the feasibility of partial system func- tion. The results show that the prototyping circuit for the proposed energy harvesting system by using DEAP can work well.
M.S. in Electrical Engineering, May 2012
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Title: A DEVICE-TO-DEVICE COMMUNICATION AND KEY EXCHANGE APPLICATION OVER WI-FI DIRECT
Creator: Hong, Weisheng
Date: 2014, 2014-12
Description: With the rapid growth of smartphone and tablet users, Device-to-Device (D2D) communications have become an attractive solution for enhancing...
Show moreWith the rapid growth of smartphone and tablet users, Device-to-Device (D2D) communications have become an attractive solution for enhancing the performance of traditional cellular networks. However, relevant security issues involved in D2D communications have not been addressed yet. In this thesis, I investigate the security requirements and challenges for D2D communications, and present a secure and efficient key agreement protocol, which enables two mobile devices to establish a share secret key for D2D without prior knowledge. The mobile devices are playing an important role in our social life. People trend to share their files and chat with each other without Wi-Fi. Wi-Fi Direct technology provides a very good way to satisfy people’s need. After established a security D2D communication, I used the socket communication method to implement the chat function between devices and some protocols to enable the files transmitted. In the file transfer function, my demo support any types of the files. In the chat function, my demo also uses the shared secret to encrypt the message and then the receiver can decrypt it with the shared secret.
M.S. in Electrical Engineering, December 2014
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Title: AN ANALYTICAL APPROACH TO REAL-TIME MISBEHAVIOR DETECTION IN IEEE 802.11 WIRELESS NETWORKS
Creator: Chen, Ying
Date: 2011-07, 2011-07
Description: It is easy for the malicious nodes to take advantage of CSMA/CA based wireless protocols to gain unfair larger share of the network throughput...
Show moreIt is easy for the malicious nodes to take advantage of CSMA/CA based wireless protocols to gain unfair larger share of the network throughput because of the distributed nature of the IEEE 802.11 distributed coordination function (DCF). The backoff misbehavior will happen when one node deliberately chooses smaller backoff parameters. This paper adopts a promising non-parametric cumulative sum test (CUSUM) based scheme to quickly find abrupt changes in a process without prior knowledge of the statistics of the change occurrences. According to a Markov chain based analytical model, we can systematically study the real-time misbehavior detection results from CUSUM based method, thus quantitatively computer the system configuration parameters for guaranteed performance in terms of average false positive rate, average detection delay, and missed detection ratio.
M.S. in Computer Engineering, July 2011
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Title: the evolution of the south fork turning basin: Grilli_Evolution
Creator: Grilli, Graham
Date: 5/4/2011, 2011-05
Description: a historical analysis of the South Fork Turning basin from 1833-2040 including proposals for future timeline. wetland remediation coupled with...
Show morea historical analysis of the South Fork Turning basin from 1833-2040 including proposals for future timeline. wetland remediation coupled with modular housing and adaptive reuse solutions. prototype for other potential developments along river's edge leading to healthier Great Lakes basin.
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