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Physiological Telemetric Sensing Systems For Medical Applications, Lun-Chen Hsu Jan 2009

Physiological Telemetric Sensing Systems For Medical Applications, Lun-Chen Hsu

Electrical Engineering Dissertations - Archive

A batteryless, wireless, sensing system, suitable for biomedical applications, was studied in this dissertation. The sensing system contains a reader and a transponder and the working principle is based on passive RFID systems. The transponder harvests the RF energy from the reader to power up the frequency generator circuit which is modulated by sensor signals. Sensor signals are encoded into frequency shifts to provide the immunity to motion artifacts and the robust performances of sensing system are demonstrated. The sensing platform can also be used for multiple sensor integration for different medical applications. In this dissertation, the physiological measurements are …

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Effects Of Voltage Unbalance And System Armonics On The Performance Of Doubly Fed Induction Wind Generators, Morgan Mozhgan Kiani Jan 2009

Effects Of Voltage Unbalance And System Armonics On The Performance Of Doubly Fed Induction Wind Generators, Morgan Mozhgan Kiani

Electrical Engineering Dissertations - Archive

Inherent difficulties in management of electric power in the presence of an increasing demand for more energy, non-conventional loads such as digital appliances, and non-sustainable imported fossil fuels has initiated a multi-folded effort by many countries to restructure the way electric energy is generated, dispatched, and consumed. Smart power grid is the manifestation of many technologies that would eventually transforms the existing power grid into a more flexible, fault resilient, and intelligent system. Integration of distributed renewable energy sources plays a central role in successful implementation of this transformation. Among the renewable options, wind energy harvesting offers superior engineering and …

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Dynamic Scene Interpretation And Understanding From Two Views, Ninad Shashikant Thakoor Jan 2009

Dynamic Scene Interpretation And Understanding From Two Views, Ninad Shashikant Thakoor

Electrical Engineering Dissertations - Archive

Interpretation of a static or dynamic scene starts by segmenting the scene followed by recognition. Our work concentrates on the general problem of segmenting and recognizing animate and inanimate objects in a scene captured from two different views. The two views here refer to either a pair of frames captured by a stereo camera or two frames (with spatial overlap) captured with a moving camera.The work described in the dissertation starts with an iterative split-and-merge framework for segmentation of an unknown number of objects captured with stereo camera. The disparity of a scene is modeled by approximating various surfaces in …

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A Novel Method For Major Harmonic Sources Identification In High Voltage Transmission Systems, Shun Liang Jan 2009

A Novel Method For Major Harmonic Sources Identification In High Voltage Transmission Systems, Shun Liang

Electrical Engineering Dissertations - Archive

Due to the proliferation of high-voltage power electronics devices and nonlinear loads connected to power systems, the penetration of produced harmonics into power transmission networks to pollute power quality of power systems has been a new concern. Recently, an electric utility company in Texas has observed that harmonic levels may exceed the recommended levels of IEEE Std. 519-1992 at some points in the 138 kV, 161 kV, and 345 kV transmission systems. In order to meet the requirement of the IEEE recommended practice and maintain the power quality of electricity delivered to consumers, identification of major harmonic sources to mitigate …

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Electrodeposited Cuprous Oxide Solar Cells, Kunhee Han Jan 2009

Electrodeposited Cuprous Oxide Solar Cells, Kunhee Han

Electrical Engineering Dissertations - Archive

The electrochemically deposited cuprous oxide (Cu2O) as a photovoltaic absorber material is introduced in this work. The electrical, structural, and optical characteristics of electrodeposited Cu2O are well investigated. The pH of the deposition solution controls the flat band voltage of Cu2O. The variation of the flat band voltage by solution pH is related to oxygen incorporation in the film, which is controlled by the amount of oxygen precursor, OH-, in the solution. Hence, the high pH in the solution is preferable for producing a p-type Cu2O with copper vacancy, while the low pH in the solution is preferable for producing …

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Mems Based Wireless Sensing And Therapeutic Systems For Biomedical Applications, Praveen Pandojirao-Sunkojirao Jan 2009

Mems Based Wireless Sensing And Therapeutic Systems For Biomedical Applications, Praveen Pandojirao-Sunkojirao

Electrical Engineering Dissertations - Archive

Miniaturized devices in vivo for accurate diagnosis and prognosis in therapy to detect various physiological parameters inside human body have been a goal for efficient healthcare. In this perspective, microelectromechanical system (MEMS) devices providing small size features and new transduction functions benefit such biomedical applications. The features in MEMS devices also allow integration of CMOS circuitry and wireless communication for electronic control as well as actuation functionalities for driving mechanical parts for scanning, moving and probing. In this work, feasibility studies for two novel sensing systems: an in vivo optical fiber based spectral optical coherence tomography (OCT) imaging system and …

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A Hybrid Method For Identifying And Estimating Key Dynamic Parameters For Exciters, Pss And Governors Based On Event-Recorded Measurements On-Line Measurements, Yunzhi Cheng Jan 2009

A Hybrid Method For Identifying And Estimating Key Dynamic Parameters For Exciters, Pss And Governors Based On Event-Recorded Measurements On-Line Measurements, Yunzhi Cheng

Electrical Engineering Dissertations - Archive

Following the power market deregulation, power systems have become more complex and are found to be consistently operating closer to their stability limits. Power system dynamic modeling and studies which provide significant insight into the dynamic characteristics of the system are bound to play increasingly critical roles. The dynamic simulation results are highly dependent on certain key parameters that govern the dynamics of the power system such as governors and/or exciters in the case of generation facilities. However, the dynamic parameters in the system database maintained by the Independent System Operator (ISO) are not accurate due to numerous reasons ranging …

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A Family Of Robust Second Order Training Algorithms, Sanjeev Sreenivasa Rao Malalur Jan 2009

A Family Of Robust Second Order Training Algorithms, Sanjeev Sreenivasa Rao Malalur

Electrical Engineering Dissertations - Archive

Starting with the concept of equivalent networks, a framework for analyzing the effect of linear dependence on training of a multi-layer perceptron is established. Detailed mathematical analyses are carried out to show that training using backpropagation and Newton's method is different under the presence of linear dependence.Two effective batch training algorithms are developed for the multilayer perceptron. First, the optimal input gain algorithm is presented, which computes an optimal gain coefficient for each input, used to update the input weights. The motivation for this algorithm comes from using equivalent networks to analyze the effect of input transformation. It is shown …

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Peon: Privacy-Enhanced Opportunistic Networks With Applications In Assistive Environments, Gauri Vakde Jan 2009

Peon: Privacy-Enhanced Opportunistic Networks With Applications In Assistive Environments, Gauri Vakde

Computer Science and Engineering Theses - Archive

Opportunistic Networking holds a great deal of potential for making communications easier and more flexible in pervasive assistive environments. However, security and privacy must be addressed to make these communications acceptable with respect to protecting patient privacy. We propose Privacy-Enhanced Opportunistic Networking (PEON), a system for using opportunistic networking in privacy-preserving way. PEON uses concepts from anonymous communications, re-routing messages through groups of peer nodes to hide the relation between the sources and destinations. We describe a set of protocols that explore a practical range of trade-offs between privacy and communication costs by modifying how closely the protocol adheres to …

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Open Main Detection In Underground Distribution Network Using Statistical Approaches, Abedalgany Abedallah Athamneh Jan 2009

Open Main Detection In Underground Distribution Network Using Statistical Approaches, Abedalgany Abedallah Athamneh

Electrical Engineering Dissertations - Archive

The continuous increase for people dependency on electrical energy to run most of their industrial, commercial and residential activities makes it necessary to regularly improve the distribution systems. This Improvement does not involve served area and system capacity increase only, but also includes service quality and system reliability enhancement. Outage is the most serious challenge that might affect the reliability of the distribution system, especially in the congested areas like New York City, where the outage is a threat for continuity of service for a large number of customers or for the important world institutions there. Outage incident in distribution …

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Objective Image And Video Quality Assessment With Applications, Qiang Li Jan 2009

Objective Image And Video Quality Assessment With Applications, Qiang Li

Electrical Engineering Dissertations - Archive

Objective Image and Video Quality Assessment (IQA/VQA) aims to automatically measure the quality degradation perceived by the human eyes. It is of fundamental importance to address a wide variety of problems in image and video processing. Based on the availability of the information about the reference image, IQA/VQA models can be classified into Full-reference (FR), Reduced-reference (RR) and No-reference (NR) IQA/VQA methods. This dissertation focuses on FRIQA/VQA, RRIQA/VQA, as well as their applications in perceptual image coding and video interpolation.First, we propose novel metrics for FRIQA/VQA based on Structural SIMilarity (SSIM) and the information theoretical weighting. The spatial information weights …

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Performance Evaluation In Reverse Logistics With Data Envelopment Analysis, Ake Tonanont Jan 2009

Performance Evaluation In Reverse Logistics With Data Envelopment Analysis, Ake Tonanont

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Good reverse logistics design can save cost, increase revenues, and gain competitive edges over the rivals. Design of the optimized reverse supply chain model is a very important task to help enterprises save cost and gain benefits from their supply chains. In this study, reverse logistics is considered as a part of the Closed Loop Supply Chain (CLSC). CLSC combines forward and reverse flow together in the supply chain. Each component in a forward and reverse supply chain results in the efficiency of CLSC. Therefore, considering forward and reverse supply chain together as a CLSC will result in more benefits …

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Software Capacity Planning: A Methodology For A Portfolio Of High Technology Product Development Projects, Rajiv Malhotra Jan 2009

Software Capacity Planning: A Methodology For A Portfolio Of High Technology Product Development Projects, Rajiv Malhotra

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

High technology product development projects make extensive use of engineering software during the product development process. The suite of engineering software tools deployed during product development represents a significant portion of the product development costs. The ability to forecast the engineering software license capacity required to support product development plans is crucial for budgeting, return on investment (ROI) calculations, contract negotiations with the software suppliers, and the provision of an IT infrastructure necessary to support the execution of the software tools. This research shows that the usage of engineering application software in high technology is cyclical due to the characteristics …

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Web Application Integration Using Mashups, Ronda Hilton Jan 2009

Web Application Integration Using Mashups, Ronda Hilton

Computer Science and Engineering Theses - Archive

The HTML DOM is the W3C standard data model for HTML documents. A web page may be viewed as a tree structure with data nodes at each level, according to the HTML DOM, to enable web applications to access it dynamically. If a web page mashes up more than one web application, the data from one web application may flow as input into another. The user may manually transfer such data piecemeal by using the mouse to cut and paste the displayed text. Instead of this tedious and error-prone repetitious method of data transfer, the mashup may contain a software …

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Multi-Port Power Electronic Interface For Renewable Energy Sources, Wei Jiang Jan 2009

Multi-Port Power Electronic Interface For Renewable Energy Sources, Wei Jiang

Electrical Engineering Dissertations - Archive

Energy intensive products and services are penetrating people's daily life as well as different sectors of industry during recent decades. Further effort to improve efficiency, reduce green house gas and hazardous particle emission lead to the emergence of the "more electric" concept in several industries including transportation. This trend, however, burdens the aging power system and existing local power networks. To offer a remedy to the problem and a smooth transition to a more reliable, more diverse, and more efficient power grid of the future, the concept of Multi-port Power Electronic Interface (MPEI) for localized power processing is introduced in …

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Pseudo-Hierarchical Ant-Based Clustering Using A Heterogeneous Agent Hierarchy And Automatic Boundary Formation, Jeremy Bernard Brown Jan 2009

Pseudo-Hierarchical Ant-Based Clustering Using A Heterogeneous Agent Hierarchy And Automatic Boundary Formation, Jeremy Bernard Brown

Computer Science and Engineering Theses - Archive

The behavior and self-organization of ant colonies has been widely studied and served as the inspiration and source of many swarm intelligence models and related clustering algorithms. Unfortunately, most models that directly mimic ants produce too many clusters and converge too slowly. A wide range of research has attempted to address this issue through various means, but a number of problems remain: 1) Ants must still physically move from one cluster to another through intermediate locations, 2) current methods for remote relocation of an item only consider one movement at time to a particular location and do not consider patterns …

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An Auction Mechanism For Grid Scheduling And Resource Allocation In The Context Of Atlas, Tengkok Aaron Thor Jan 2009

An Auction Mechanism For Grid Scheduling And Resource Allocation In The Context Of Atlas, Tengkok Aaron Thor

Computer Science and Engineering Dissertations - Archive

The technological advancements in the areas of computing and networking over the recent years have led to an emerging infrastructure known as Computational Grids, which provides users with the flexibility of pervasive access to enormous computational resources hosted at remote locations. Effective resource management and job scheduling poses a challenge when constraints such as resource utilization, response time, global and local policies need to be taken into account, while dealing with potentially independent sources of jobs, computational, and storage resources. It must be ensured that scheduling decisions made are still valid by the time a job is to be executed, …

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Design And Analysis Of Application Architecture For Opportunistic Networks Using Ad Hoc Wi-Fi, Sankalp Vinod Shere Jan 2009

Design And Analysis Of Application Architecture For Opportunistic Networks Using Ad Hoc Wi-Fi, Sankalp Vinod Shere

Computer Science and Engineering Theses - Archive

In recent years, the number of smartphone users has increased by many folds. In fact, it is estimated to reach 100 million by 2013. Current generation of smartphones has better storage, battery, computing capabilities and they come equipped with short range communication technologies like Bluetooth and Wi-Fi. These improved capabilities coupled with staggering rise in number of users, has prompted growing interest in smartphone applications that help users to communicate with each other directly and over the internet. In particular as a result, when a large number of mobile users can communicate directly with each other during opportunistic contacts when …

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Reactive Control Composition For Mobile Manipulators, Binu George Mathew Jan 2009

Reactive Control Composition For Mobile Manipulators, Binu George Mathew

Computer Science and Engineering Theses - Archive

A mobile manipulator is a manipulator mounted on a mobile platform. Due to this combination it has increased mobility compared to a fixed manipulator and increased dexterity compared to a mobile platform. At the same time it has a significantly higher number of degrees of freedom than fixed manipulators or mobile platforms and an increased task and workspace. In particular, the size of the workspace of the manipulator is restricted only by the workspace limitations of the mobile platform and the obstacles around the goal location. In addition, the extra degrees of freedom increase the number of ways in which …

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Millimeter Scale Robots For The Nanofactory, Rakesh Murthy Jan 2009

Millimeter Scale Robots For The Nanofactory, Rakesh Murthy

Electrical Engineering Dissertations - Archive

The top down approach is a commonly employed miniaturization pathway into micro and nanomanufacturing. Its popularity is due to the fact that it adapts traditionally engineered macro scale positioning, manipulation and processing technology with micro and nano scale precision and part sizes. However, state of the art top down systems such as the Atomic Force Microscope (AFM) span four to five orders of magnitude larger than the parts being handled. This dissertation addresses the need for creating millimeter size robotic positioning technology that closes the size gap between equipment and part sizes. Such microrobot manufacturing methodology comprising of micro component-level …

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Design And Analysis Of A Mobile File Sharing System For Opportunistic Networks, Gautam Ravendra Chavan Jan 2009

Design And Analysis Of A Mobile File Sharing System For Opportunistic Networks, Gautam Ravendra Chavan

Computer Science and Engineering Theses - Archive

In the past several years, wireless mobile devices with advanced computing, sensing, and storing capabilities have been increasingly developed by handset manufacturers, deployed by wireless carriers, and accepted by consumers. A prominent example is the vast success of Apple's iPhone, which witnessed a sale of 1 million units during the first 3 days of sales for its new version iPhone 3GS. As a result of the increasing popularity of these mobile devices, users can carry, utilize, and exchange information embedded therein, ideally wherever they go and whenever they want. A prominent scenario is where information is exchanged among users when …

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Online Adaptive Optimal Control For Continuous-Time Systems, Draguna Vrabie Jan 2009

Online Adaptive Optimal Control For Continuous-Time Systems, Draguna Vrabie

Electrical Engineering Dissertations - Archive

This work makes two major contributions. * First, in the field of computational intelligence, it develops reinforcement learning controllers (i.e. approximate dynamic programming algorithms) for continuous-time systems, whereas in the past, reinforcement learning has been mainly developed for discrete-time systems. * Second, in the field of control systems engineering, it develops on-line optimal adaptive controllers, whereas in the past, optimal control has been an off-line design tool, and on-line adaptive controllers have not been optimal. The online algorithms presented herein are reinforcement learning schemes which provide online synthesis of optimal control for a class of nonlinear systems with unknown drift …

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The Reputation System For Robust, Structured P2p Systems, Apurv Ashok Dhadphale Jan 2009

The Reputation System For Robust, Structured P2p Systems, Apurv Ashok Dhadphale

Computer Science and Engineering Theses - Archive

Structured peer-to-peer systems are distributed communication systems that typically use Distributed Hash Table (DHT) indexing to efficiently locate the resources. These networks are highly scalable and can route the messages correctly even for the extremely dynamic environment. But these networks are vulnerable; even a small fraction of malicious nodes can bias the lookup results when they are present on a lookup path. In our thesis, we address this problem of reliably searching the insecure p2p networks. We propose a reputation system to reduce the number of failed lookups and make the networks more robust. For our study, the concept is …

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Automated 3d Microassembly With Precision Adjusted Hybrid Supervisory Controller, Choudhury Aditya Narayan Das Jan 2009

Automated 3d Microassembly With Precision Adjusted Hybrid Supervisory Controller, Choudhury Aditya Narayan Das

Electrical Engineering Dissertations - Archive

Unlike semiconductor integrated circuits (ICs), newer microsystems combine sensors, actuators, mechanical structures, electronics, and optics on a single substrate. In such a diversified system, heterogeneous manipulation of the components becomes unavoidable. In an effort to find a solution to reduced yields and speeds in manufacturing at the micro-scale, research initiated in 1990s has sought to understand top-down aspects of micromanipulation, sensor-based precision control of robots, self alignment effects using compliant micro structure designs, and so on. From these researches, automated microassembly emerges as an enabling technology for micro manufacturing that offers well-known pathways to building heterogeneous microsystems with a higher …

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A Microfluidic Platform To Study Cell Migration, Smitha Malalur Nagaraja Rao Jan 2009

A Microfluidic Platform To Study Cell Migration, Smitha Malalur Nagaraja Rao

Electrical Engineering Dissertations - Archive

Migration of cancer cells from the primary organ to distant sites is critical to the development of malignant metastasis. This is partly dependant on the various chemical factors present in the blood serum. Cell motility studies using conventional Boyden chamber assays require high volumes of reagents. The measurement provides only an end-point result and time-lapse study of the cell deformation and migration cannot be performed. We have designed and evaluated a poly-dimethylsiloxane (PDMS) microfluidic device in order to study cell migration in the presence of gradients. Photolithography and soft lithography processes were used to fabricate the PDMS devices from the …

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Liquid: A Detection Resistant Covert Timing Channel Based On Ipd Shaping, Robert J. Walls Jan 2009

Liquid: A Detection Resistant Covert Timing Channel Based On Ipd Shaping, Robert J. Walls

Computer Science and Engineering Theses - Archive

Covert timing channels provide a way to surreptitiously leak information from an entity in a higher-security level to an entity in a lower level. The difficulty of detecting or eliminating such channels makes them a desirable choice for adversaries that value stealth over throughput. When one considers the possibility of such channels transmitting information across network boundaries, the threat becomes even more acute. A promising technique for detecting covert timing channels focuses on using entropy-based tests. This method is able to reliably detect known covert timing channels by using a combination of entropy and conditional entropy to detect anomalies in …

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Performance Analysis And Comparison Of Dirac Video Codec With H.264 / Mpeg-4 Part 10 Avc, Aruna Ravi Jan 2009

Performance Analysis And Comparison Of Dirac Video Codec With H.264 / Mpeg-4 Part 10 Avc, Aruna Ravi

Electrical Engineering Theses - Archive

Dirac is a hybrid motion-compensated state-of-the-art video codec that uses modern techniques such as wavelet transforms and arithmetic coding. It is an open technology, designed to avoid patent infringement and can be used without the payment of license fees. It is well suited to the business model of public service broadcasters as it can be easily recreated for new platforms. Dirac is aimed at applications ranging from HDTV (high definition television) to web streaming.H.264, MPEG-4 part-10 or AVC, is the latest digital video codec standard which has proven to be superior than earlier standards in terms of compression ratio, quality, …

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The Facial Masculinity Of Women In Sex Segregated Occupations, Chawki Ahmed Belhadi Jan 2009

The Facial Masculinity Of Women In Sex Segregated Occupations, Chawki Ahmed Belhadi

Sociology & Anthropology Theses - Archive

This purpose of the study was to bring more definition to the "problem" of occupational sex segregation, specifically why male-dominated occupations like engineering, firefighting, and the military still remain sex segregated. The study attempted to do so by integrating two findings: 1) the finding that women in male-dominated occupations are more dominant than women in female-dominated occupations, and 2) the finding that facially masculine women are more dominant than facially submissive women. Facial photos of women from occupations that are at least 90% male dominated and at least 90% female dominated were culled from the internet and rated for their …

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An Integrated Framework For Qos-Aware Data Reporting In Wireless Sensor Networks, Hyun Jung Choe Jan 2009

An Integrated Framework For Qos-Aware Data Reporting In Wireless Sensor Networks, Hyun Jung Choe

Computer Science and Engineering Dissertations - Archive

Wireless sensor networks are being deployed in a wide variety of applications such as environment monitoring, smart buildings, security, machine surveillance system, and so on.The deployment of sensor networks for a specific sensing application enhances the ability to control and examine the physical environments while collecting meaningful information from the monitoring area.In densely deployed networks, the sensor nodes located in an adjacent area detect the targeted phenomena in its sensing range and report the gathered (raw or processed) data to designated sinks via single-hop or multi-hop communication paths.Although the correlation of data from proximity sensors cause overheads in terms of …

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Autonomous Abstraction Of Policies Based On Policy Homomorphism, Srividhya Rajendran Jan 2009

Autonomous Abstraction Of Policies Based On Policy Homomorphism, Srividhya Rajendran

Computer Science and Engineering Dissertations - Archive

A life long learning agent performing in a complex and dynamic environment needs the ability to learn increasingly complex tasks over time. These agents over their lifetime have to learn new tasks, adapt the policies of already learned tasks and extract and reuse the knowledge gained to learn new, more complex tasks. To do this, they need methods that allow them to autonomously extract knowledge from the already learned policy instances and reuse the knowledge gained to learn related tasks in novel environments.This dissertation presents a novel approach that enables an agent to autonomously abstract reusable skills and concepts using …

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