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Missouri University of Science and Technology

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Articles 1261 - 1290 of 1938

Full-Text Articles in Computer Sciences

Adaptive Dynamic Programming-Based Optimal Control Of Unknown Affine Nonlinear Discrete-Time Systems, Travis Dierks, Balaje T. Thumati, S. Jagannathan Nov 2009

Adaptive Dynamic Programming-Based Optimal Control Of Unknown Affine Nonlinear Discrete-Time Systems, Travis Dierks, Balaje T. Thumati, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Discrete time approximate dynamic programming (ADP) techniques have been widely used in the recent literature to determine the optimal or near optimal control policies for nonlinear systems. However, an inherent assumption of ADP requires at least partial knowledge of the system dynamics as well as the value of the controlled plant one step ahead. in this work, a novel approach to ADP is attempted while relaxing the need of the partial knowledge of the nonlinear system. the proposed methodology entails a two-part process: online system identification and offline optimal control training. First, in the identification process, a neural network (NN) …

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Decentralized Control Of Large Scale Interconnected Systems Using Adaptive Neural Network-Based Dynamic Surface Control, Shahab Mehraeen, Sarangapani Jagannathan, Mariesa L. Crow Nov 2009

Decentralized Control Of Large Scale Interconnected Systems Using Adaptive Neural Network-Based Dynamic Surface Control, Shahab Mehraeen, Sarangapani Jagannathan, Mariesa L. Crow

Electrical and Computer Engineering Faculty Research & Creative Works

A novel decentralized controller using the dynamic surface control (DSC) is proposed for a class of uncertain large scale interconnected nonlinear systems in strict feedback form while relaxing the "explosion of complexity" problem which is observed in the typical backstepping approach. the matching condition is not assumed when dealing with the interconnection terms. Neural networks (NNs) are utilized to approximate the uncertainties in both subsystem and interconnected terms. by using novel NN weight update laws, it is demonstrated using Lyapunov stability that the closed-loop signals are asymptotically stable in the presence of NN approximation errors in contrast with the uniform …

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On Transport Protocol Performance Measurement Over 10gbps High Speed Optical Networks, Yixin Wu, Suman Kumar, Seung Jong Park Nov 2009

On Transport Protocol Performance Measurement Over 10gbps High Speed Optical Networks, Yixin Wu, Suman Kumar, Seung Jong Park

Computer Science Faculty Research & Creative Works

With the integration of IP and optical technology, fast optical network (of the order of 10Gbps) has emerged to support international research cooperation such as massive scientific data transfer and next generation Internet related research. Therefore, it is important to analyze the measurement issues to guide the high-speed transport protocol research for high-speed optical network of the order of 10Gbps. The objectives of this paper are as follows: i) determine the suitability of TCP parameters such as Jumbo Frame size, TCP sender and receiver buffer sizes; ii) evaluate TCP performance measurement tools and emulation tools over 10Gbps high speed optical …

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Adaptive Distributed Fair Scheduling For Multiple Channels In Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani, Steve Eugene Watkins, James W. Fonda Nov 2009

Adaptive Distributed Fair Scheduling For Multiple Channels In Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani, Steve Eugene Watkins, James W. Fonda

Electrical and Computer Engineering Faculty Research & Creative Works

A novel adaptive and distributed fair scheduling (ADFS) scheme for wireless sensor networks (WSN) in the presence of multiple channels (MC-ADFS) is developed. The proposed MC-ADFS increases available network capacity and focuses on quality-of-service (QoS) issues. when nodes access a shared channel, the proposed MC-ADFS allocates the channel bandwidth proportionally to the packet's weight which indicates the priority of the packet's flow. The packets are dynamically assigned to channels based on the packet weight and current channel utilization. The dynamic assignment of channels is facilitated by use of receiver-based allocation and alternative routes. Moreover, MC-ADFS allows the dynamic allocation of …

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Working Session: Using Eye-Tracking To Understand Program Comprehension, Yann Gaël Guéhéneuc, Huzefa Kagdi, Jonathan I. Maletic Oct 2009

Working Session: Using Eye-Tracking To Understand Program Comprehension, Yann Gaël Guéhéneuc, Huzefa Kagdi, Jonathan I. Maletic

Computer Science Faculty Research & Creative Works

The working session focuses on the use of eye-tracking technology to assess, understand, and evaluate tools and techniques for program comprehension. an introduction to the technology and tools of eye-tracking will be presented. a discussion of how these tools augment existing evaluation mechanism in the context of program comprehension will follow. Research directions and open problems will be a main topic. © 2009 IEEE.

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Contribution Based Priority Assessment In A Web-Based Intelligent Argumentation Network For Collaborative Software Development, Xiaoqing Frank Liu, Maithili Satyavolu, Ming-Chuan Leu Oct 2009

Contribution Based Priority Assessment In A Web-Based Intelligent Argumentation Network For Collaborative Software Development, Xiaoqing Frank Liu, Maithili Satyavolu, Ming-Chuan Leu

Computer Science Faculty Research & Creative Works

Decision making is an important aspect in a collaborative software development process which involves a complex process of conflict resolution. the priority of the participants plays a vital role in conflict resolution as the decision-making process involves many participants from multiple perspectives. the priority assessment methods used in the process so far are usually static in nature, i.e., the priorities of the participants remain constant throughout the decision-making process. in order to make the collaborative system closer to real world scenarios, we incorporate dynamic priority assessment into a web-Based collaborative system based on intelligent computational argumentation, which was developed in …

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Reinforcement-Learning-Based Output-Feedback Control Of Nonstrict Nonlinear Discrete-Time Systems With Application To Engine Emission Control, Peter Shih, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier Oct 2009

Reinforcement-Learning-Based Output-Feedback Control Of Nonstrict Nonlinear Discrete-Time Systems With Application To Engine Emission Control, Peter Shih, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier

Electrical and Computer Engineering Faculty Research & Creative Works

A novel reinforcement-learning-based output adaptive neural network (NN) controller, which is also referred to as the adaptive-critic NN controller, is developed to deliver the desired tracking performance for a class of nonlinear discrete-time systems expressed in nonstrict feedback form in the presence of bounded and unknown disturbances. The adaptive-critic NN controller consists of an observer, a critic, and two action NNs. The observer estimates the states and output, and the two action NNs provide virtual and actual control inputs to the nonlinear discrete-time system. The critic approximates a certain strategic utility function, and the action NNs minimize the strategic utility …

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Complexities Of Information Security In Cyber-Physical Power Systems, Bruce Mcmillin Sep 2009

Complexities Of Information Security In Cyber-Physical Power Systems, Bruce Mcmillin

Computer Science Faculty Research & Creative Works

Cyber-Physical Power Systems consist of significant cyber components that mange the physical electric power infrastructure under distributed control of power electronics devices. This represents a departure from more centralized SCADA-type control. NERC Critical Infrastructure Protection standards emphasize the need to protect the power infrastructure from both cyber and physical attacks. Complex interactions between the cyber and physical worlds introduce new vulnerabilities that go beyond those found in the purely computer world. in this paper, some of these new vulnerabilities are described and a direction is suggested to determine and mitigate these vulnerabilities. © 2009 IEEE.

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Secure Hierarchical Data Aggregation In Wireless Sensor Networks, Julia Albath, Sanjay Madria Sep 2009

Secure Hierarchical Data Aggregation In Wireless Sensor Networks, Julia Albath, Sanjay Madria

Computer Science Faculty Research & Creative Works

Communication in wireless sensor networks uses the majority of a sensor's limited energy. using aggregation in wireless sensor network reduces the overall communication cost. Security in wireless sensor networks entails many different challenges. Traditional end-to-end security is not suitable for use with in-network aggregation. a corrupted sensor has access to the data and can falsify results. Additively homomorphic encryption allows for aggregation of encrypted values, with the result being the same as the result when unencrypted data was aggregated. using public key cryptography, digital signatures can be used to achieve integrity. We propose a new algorithm using homomorphic encryption and …

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Node Security In Hierarchical Sensor Networks: Distribution Of Functions Versus Keys, Biswajit Panja, Sanjay Madria Sep 2009

Node Security In Hierarchical Sensor Networks: Distribution Of Functions Versus Keys, Biswajit Panja, Sanjay Madria

Computer Science Faculty Research & Creative Works

Secure communication involving cluster heads in a sensor network is vital as they are responsible for data aggregation and for taking important decisions in their groups. in this article, we propose a scheme for secure communication via such nodes in a sensor network. in our approach, the base station provides a function to the cluster head of each group, which is used to compute the key for the secure communication with the base station. the protocol is first elucidated for a fixed cluster head in each group and later it is extended for dynamic cluster heads. Each function is computed …

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Reliability Analysis For The Advanced Electric Power Grid: From Cyber Control And Communication To Physical Manifestations Of Failure, Ayman Z. Faza, Sahra Sedigh, Bruce M. Mcmillin Sep 2009

Reliability Analysis For The Advanced Electric Power Grid: From Cyber Control And Communication To Physical Manifestations Of Failure, Ayman Z. Faza, Sahra Sedigh, Bruce M. Mcmillin

Electrical and Computer Engineering Faculty Research & Creative Works

The advanced electric power grid is a cyber-physical system comprised of physical components, such as transmission lines and generators, and a network of embedded systems deployed for their cyber control. The objective of this paper is to qualitatively and quantitatively analyze the reliability of this cyber-physical system. The original contribution of the approach lies in the scope of failures analyzed, which crosses the cyber-physical boundary by investigating physical manifestations of failures in cyber control. As an example of power electronics deployed to enhance and control the operation of the grid, we study Flexible AC Transmission System (FACTS) devices, which are …

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T-Plausibility: Semantic Preserving Text Sanitization, Wei Jiang, Mummoorthy Murugesan, Chris Clifton, Luo Si Aug 2009

T-Plausibility: Semantic Preserving Text Sanitization, Wei Jiang, Mummoorthy Murugesan, Chris Clifton, Luo Si

Computer Science Faculty Research & Creative Works

Text documents play significant roles in decision making and scientific research. Under federal regulations, documents (e.g., pathology records) containing personally identifiable information cannot be shared freely, unless properly sanitized. Generally speaking, document sanitization consists of finding and hiding personally identifiable information. The first task has received much attention from the research community, but the main strategy for the second task has been to simply remove personal identifiers and very sensitive information (e.g., diseases and treatment). It is not hard to see that if important information (e.g., diagnoses and personal medical histories) is completely removed from pathology records, these records are …

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Joint Routing And Link Rate Allocation Under Bandwidth And Energy Constraints In Sensor Networks, Maggie Cheng, Xuan Gong, Lin Cai Jul 2009

Joint Routing And Link Rate Allocation Under Bandwidth And Energy Constraints In Sensor Networks, Maggie Cheng, Xuan Gong, Lin Cai

Computer Science Faculty Research & Creative Works

In sensor networks, both energy and bandwidth are scarce resources. in the past, many energies efficient routing algorithms have been devised in order to maximize network lifetime, in which wireless link bandwidth has been optimistically assumed to be sufficient. This article shows that ignoring the bandwidth constraint can lead to infeasible routing solutions. as energy constraint affects how data should be routed, link bandwidth also affects not only the routing topology but also the allowed data rate on each link. in this paper, we discuss the sufficient condition on link bandwidth that makes a routing solution feasible, then provide mathematical …

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Consistency Management Strategies For Data Replication In Mobile Ad Hoc Networks, Takahiro Hara, Sanjay Kumar Madria Jul 2009

Consistency Management Strategies For Data Replication In Mobile Ad Hoc Networks, Takahiro Hara, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

In a mobile ad hoc network, data replication drastically improves data availability. However, since mobile hosts' mobility causes frequent network partitioning, consistency management of data operations on replicas becomes a crucial issue. In such an environment, the global consistency of data operations on replicas is not desirable by many applications. Thus, new consistency maintenance based on local conditions such as location and time need to be investigated. This paper attempts to classify different consistency levels according to requirements from applications and provides protocols to realize them. We report simulation results to investigate the characteristics of these consistency protocols in a …

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Rfid-Based Smart Freezer, Ahmet Soylemezoglu, Maciej Jan Zawodniok, Jagannathan Sarangapani Jul 2009

Rfid-Based Smart Freezer, Ahmet Soylemezoglu, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel radio-frequency identification (RFID)-based smart freezer using a new inventory-management scheme for extremely low temperature environments. The proposed solution utilizes backpressure inventory control, systematic selection of antenna configuration, and antenna power control. The proposed distributed-inventory-control (DIC) scheme dictates the amount of items transferred through the supply chain. when a high item visibility is ensured, the control scheme maintains the desired level of inventory at each supply-chain echelon. The performance of the DIC scheme is guaranteed using a Lyapunov-based analysis. The proposed RFID antenna-configuration design methodology coupled with locally asymptotically stable distributed power control ensures a 99% …

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Optimal Control Of Unknown Affine Nonlinear Discrete-Time Systems Using Offline-Trained Neural Networks With Proof Of Convergence, Travis Dierks, Balaje T. Thumati, S. Jagannathan Jul 2009

Optimal Control Of Unknown Affine Nonlinear Discrete-Time Systems Using Offline-Trained Neural Networks With Proof Of Convergence, Travis Dierks, Balaje T. Thumati, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

The optimal control of linear systems accompanied by quadratic cost functions can be achieved by solving the well-known Riccati equation. However, the optimal control of nonlinear discrete-time systems is a much more challenging task that often requires solving the nonlinear Hamilton-Jacobi-Bellman (HJB) equation. in the recent literature, discrete-time approximate dynamic programming (ADP) techniques have been widely used to determine the optimal or near optimal control policies for affine nonlinear discrete-time systems. However, an inherent assumption of ADP requires the value of the controlled system one step ahead and at least partial knowledge of the system dynamics to be known. in …

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Incentive Based Routing Protocol For Mobile Peer To Peer Networks, Anil Jade, Sanjay Kumar Madria, Mark Linderman May 2009

Incentive Based Routing Protocol For Mobile Peer To Peer Networks, Anil Jade, Sanjay Kumar Madria, Mark Linderman

Computer Science Faculty Research & Creative Works

Incentive models are becoming increasingly popular in Mobile Peer to Peer Networks (M-P2P) as these models entice node participation in return for a virtual currency to combat free riding and to effectively manage constraint resources in the network. Many routing protocols proposed are based on best effort data traffic policy, such as the shortest route selection (hop minimization). Using virtual currency to find a cost effective optimal route from the source to the destination, while considering Quality of Service (QoS) aspects such as bandwidth and service capacity constraints for data delivery, remains a challenging task due to the presence of …

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Em Enforcing Information Flow Properties Using Compensating Events, Thoshitha T. Gamage, Bruce M. Mcmillin Apr 2009

Em Enforcing Information Flow Properties Using Compensating Events, Thoshitha T. Gamage, Bruce M. Mcmillin

Computer Science Faculty Research & Creative Works

Deeply embedded infrastructures are pervasive systems that have significant cyber and physical components, interacting with each other in complex ways. These interactions can violate a system's security policy leading to unintended information flow. Execution Monitor (EM) enforceability is the concept of monitoring a system during runtime for any security policy violations and terminating the execution if such violations occur. EM enforceable mechanisms require that the properties being enforced be restricted to safety properties. Information flow properties are considered non-EM enforceable because they cannot be defined using safety properties. to bridge this gap, prior work has presented a monitor that predicts …

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Neural Network Control Of Mobile Robot Formations Using Rise Feedback, Jagannathan Sarangapani, Travis Alan Dierks Apr 2009

Neural Network Control Of Mobile Robot Formations Using Rise Feedback, Jagannathan Sarangapani, Travis Alan Dierks

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, an asymptotically stable (AS) combined kinematic/torque control law is developed for leader-follower-based formation control using backstepping in order to accommodate the complete dynamics of the robots and the formation, and a neural network (NN) is introduced along with robust integral of the sign of the error feedback to approximate the dynamics of the follower as well as its leader using online weight tuning. It is shown using Lyapunov theory that the errors for the entire formation are as and that the NN weights are bounded as opposed to uniformly ultimately bounded stability which is typical with most …

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Dynamic Channel Allocation In Wireless Networks Using Adaptive Learning Automata, Behdis Eslamnour, Maciej Jan Zawodniok, Jagannathan Sarangapani Apr 2009

Dynamic Channel Allocation In Wireless Networks Using Adaptive Learning Automata, Behdis Eslamnour, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

The bandwidth utilization of a single channel-based wireless networks decreases due to congestion and interference from other sources and therefore transmission on multiple channels are needed. In this paper, we propose a distributed dynamic channel allocation scheme for wireless networks using adaptive learning automata whose nodes are equipped with single radio interfaces so that a more suitable channel can be selected. The proposed scheme, adaptive pursuit reward-inaction, runs periodically on the nodes, and adaptively finds the suitable channel allocation in order to attain a desired performance. A novel performance index, which takes into account the throughput and the energy consumption, …

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A Multi-Interface Multi-Channel Routing (Mmcr) Protocol For Wireless Ad Hoc Networks, Reghu Anguswamy, Maciej Jan Zawodniok, Jagannathan Sarangapani Apr 2009

A Multi-Interface Multi-Channel Routing (Mmcr) Protocol For Wireless Ad Hoc Networks, Reghu Anguswamy, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Multiple non-interfering channels are available in 802.11 and 802.15.4 based wireless networks. Capacity of such channels can be combined to achieve a better performance thus providing a higher quality of service (QoS) than for a single channel network. However, existing routing protocols often are not suited to fully take advantage of these channels. The proposed multi-interface multi-channel routing (MMCR) protocol considers various QoS parameters such as throughput, end-to-end delay, and energy utilization as a single unified cost metric and identifies the route that optimizes the cost metric and balances the traffic among the channels on a per flow basis. Multipoint …

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Generalized Neuron Based Secure Media Access Control Protocol For Wireless Sensor Networks, Raghavendra V. Kulkarni, Ganesh K. Venayagamoorthy, Abhishek V. Thakur, Sanjay Kumar Madria Mar 2009

Generalized Neuron Based Secure Media Access Control Protocol For Wireless Sensor Networks, Raghavendra V. Kulkarni, Ganesh K. Venayagamoorthy, Abhishek V. Thakur, Sanjay Kumar Madria

Electrical and Computer Engineering Faculty Research & Creative Works

Security plays a pivotal role in most applications of wireless sensor networks. It is common to find inadequately secure networks confined only to controlled environments. The issue of security in wireless sensor networks is a hot research topic for over a decade. This paper presents a compact generalized neuron (GN) based medium access protocol that renders a CSMA/CD network secure against denial-of-service attacks launched by adversaries. The GN enhances the security by constantly monitoring multiple parameters that reflect the possibility that an attack is launched by an adversary. Particle swarm optimization, a popular bio-inspired evolutionary-like optimization algorithm is used for …

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Analysis Of Privacy And Security Policies, Elisa Bertino, Carolyn Brodie, Seraphin Calo, Lorrie Faith Cranor, Clare Marie Karat, John Karat, Ninghui Li, Dan Lin, Jorge Lobo, Qun Ni, Prathima Rao, Xiping Wang Jan 2009

Analysis Of Privacy And Security Policies, Elisa Bertino, Carolyn Brodie, Seraphin Calo, Lorrie Faith Cranor, Clare Marie Karat, John Karat, Ninghui Li, Dan Lin, Jorge Lobo, Qun Ni, Prathima Rao, Xiping Wang

Computer Science Faculty Research & Creative Works

The distributed nature of the environment in which privacy and security policies operate requires tools that help enforce consistency of policy rules across different domains. Furthermore, because changes to policy rules are required as policies evolve over time, such tools can be used by policy administrators to ensure the consistency of policy changes. in this paper, we describe a number of different policy analysis tools and techniques that we have developed over the years and present them in a unified framework in which both privacy and security policies are discussed. We cover dominance analyses of general policies, conflicts among authorizations …

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The Effects Of Technology On Literacy(S), Thomas Glen Petersen Jan 2009

The Effects Of Technology On Literacy(S), Thomas Glen Petersen

Masters Theses

"One of the challenges when measuring the effects of technology on literacy(s) is finding a control group where technology; does not play a major role in the culture. The Amish successfully live in a Technocracy where mechanical/electronic tools are used only when absolutely necessary; the Amish are not dependent on them for survival. The crux of the Amish philosophy is humility, serving the community and serving God. Ironically, they have suffered tremendous repercussions for adopting a wholesome, selfless lifestyle which is contrary to most popular world views, regardless of religious or spiritual views"--Purpose, page 40.

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Optimal Tracking Control Of Affine Nonlinear Discrete-Time Systems With Unknown Internal Dynamics, Travis Dierks, Sarangapani Jagannathan Jan 2009

Optimal Tracking Control Of Affine Nonlinear Discrete-Time Systems With Unknown Internal Dynamics, Travis Dierks, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, direct dynamic programming techniques are utilized to solve the Hamilton Jacobi-Bellman equation forward-in-time for the optimal tracking control of general affine nonlinear discrete-time systems using online approximators (OLA's). the proposed approach, referred as adaptive dynamic programming (ADP), is utilized to solve the infinite horizon optimal tracking control of affine nonlinear discrete-time systems in the presence of unknown internal dynamics and a known control coefficient matrix. the design is implemented using OLA's to realize the optimal feedback control signal and the associated cost function. the feedforward portion of the control input is derived and approximated using an additional …

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An Improved Upfc Control For Oscillation Damping, Jagannathan Sarangapani, Mariesa Crow, Jianjun Guo Jan 2009

An Improved Upfc Control For Oscillation Damping, Jagannathan Sarangapani, Mariesa Crow, Jianjun Guo

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a new control approach for a unified power flow controller (UPFC) for power system oscillation damping. This control is simple to implement, yet is valid over a wide range of operating conditions. It is also effective in the presence of multiple modes of oscillation. The proposed control is implemented in several test systems and is compared against a traditional PI control.

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Automated Offspring Sizing In Evolutionary Algorithms, André Chidi Nwamba Jan 2009

Automated Offspring Sizing In Evolutionary Algorithms, André Chidi Nwamba

Masters Theses

"Evolutionary Algorithms (EAs) are a class of algorithms inspired by biological evolution. EAs are applicable to a wide range of problems; however, there are a number of parameters to set in order to use an EA. The performance of an EA is extremely sensitive to these parameter values; setting these parameters often requires expert knowledge of EAs. This prevents EAs from being more widely adopted by nonexperts. Parameter control, the automation of dynamic parameter value selection, has the potential to not only alleviate the burden of parameter tuning, but also to improve performance of EAs on a variety of problem …

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Comparison Of Dashboard-Based And Balanced Scorecard-Based Corporate Performance Management System, Lin Zhu Jan 2009

Comparison Of Dashboard-Based And Balanced Scorecard-Based Corporate Performance Management System, Lin Zhu

Masters Theses

"Under current hypercompetitive and technology driven economic environment, more companies are using a corporate performance management (CPM) system to gain more accurate understandings of the company goals and strategies and to craft methods of achieving those goals and strategies. While CPM systems are generally implemented in two approaches: dashboard approach and scorecard approach, very few studies examine the effectiveness of each type of CPM systems implementation. Therefore, the main objective of this study is to assess the effectiveness of a dashboard based and a balanced scorecard based corporate performance management system. The effectiveness is examined through management effectiveness, degree of …

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Satellite Photography: Instrumental, Rhetorical, Affective?, Irangi Kaushalya Egodapitiya Jan 2009

Satellite Photography: Instrumental, Rhetorical, Affective?, Irangi Kaushalya Egodapitiya

Masters Theses

"This study examines how tsunami satellite images operate and could provoke various interpretations. The goal of this research project is to study whether the interpretation of tsunami satellite images could extend beyond scientific features to affective messages. Primarily based on the satellite images of Sri Lanka taken before and during the 2004 tsunami, this study analyses: How could mechanical satellite images, taken automatically by a machine in orbit, become an object of profound emotional meaning?; How do viewer's experiences, knowledge, and discourse affect their interpretations of mechanical artifacts?; How are tsunami satellite images connected to affective responses by viewers?; How …

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Information Flow Properties For Cyber-Physical Systems, Rav Akella Jan 2009

Information Flow Properties For Cyber-Physical Systems, Rav Akella

Masters Theses

"In cyber-physical systems, which are the integrations of computational and physical processes, security properties are difficult to enforce. Fundamentally, physically observable behavior leads to violations of confidentiality. This work analyzes certain noninterference based security properties to ensure that interactions between the cyber and physical processes preserve confidentiality. A considerable barrier to this analysis is the representation of physical system interactions at the cyber-level. This thesis presents encoding of these physical system properties into a discrete event system and represents the cyber-physical system using Security Process Algebra (SPA). The model checker, Checker of Persistent Security (CoPS) shows Bisimulation based NonDeducibility on …

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