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Effect Of Leachate Recirculation On Methane Generation Of A Bioreactor Landfill, Shahed R. Manzur Jan 2010

Effect Of Leachate Recirculation On Methane Generation Of A Bioreactor Landfill, Shahed R. Manzur

Civil Engineering Theses - Archive

Municipal solid waste (MSW) disposal is of current concern due to the green-house effect and rising temperature all around the globe. Landfill gas is generated from aerobic & anaerobic biodegradation of organic materials in municipal solid waste (MSW) landfill. Along with leachate, generation of Methane happens to be a by-product of the entire biodegradation process in MSW landfills. Conventional landfilling or dry cell concept minimizes the amount of moisture infiltration into the waste. In contrast, Enhanced Leachate Recirculation (ELR) or bioreactor operation facilitates leachate recirculation and distribution through the landfill that leads both reduction of time for waste stabilization and …

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Complexity Reduction For Vp6 To H.264 Transcoder Using Motion Vector Reuse, Jay R. Padia Jan 2010

Complexity Reduction For Vp6 To H.264 Transcoder Using Motion Vector Reuse, Jay R. Padia

Electrical Engineering Theses - Archive

VP6 is a video coding standard developed by On2 Technologies, Inc. It is the preferred codec for Macromedia Flash 8 video. VP6 gained importance with Macromedia Flash emerging as a widely adopted video streaming technology over the internet. H.264 is currently one of the most widely accepted video coding standards in the industry. It enables high quality video at low bitrates. Adobe adopted H.264 for its Flash video in August 2007. Adobe looks at adoption of H.264 as a major step towards enabling high quality video on the web. Hence there is increasing importance of techniques which can convert video …

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Implementation And Performance Analysis Of 2-D Order 16 Integer Transforms In H.264/Avc And Avs-Video For High Definition Video Coding, Madhu Peringassery Krishnan Jan 2010

Implementation And Performance Analysis Of 2-D Order 16 Integer Transforms In H.264/Avc And Avs-Video For High Definition Video Coding, Madhu Peringassery Krishnan

Electrical Engineering Theses - Archive

H.264/AVC and AVS-video are two video coding standards that have a wide range of applications ranging from high-end professional camera and editing systems to low-end mobile applications. They strive to achieve maximum compression efficiency without compromising the quality of video. To this end many coding tools are defined in them. Transform coding is one among them. Transform coding represents the signal/image (that is currently in time/spatial domain) in another domain (transform domain), where most of the energy in signal/image is concentrated in a fewer number of coefficients. Thus the insignificant coefficients can be discarded after transform coding to achieve compression. …

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Physics Behind Rfid Smart Card Security In Context Of Privacy, Kirti Chopra Jan 2010

Physics Behind Rfid Smart Card Security In Context Of Privacy, Kirti Chopra

Electrical Engineering Theses - Archive

In this thesis I prove that existing HF protocol is not secure. Lack of security in turn leads to violation of privacy.The unique ID on the HF RFID smart card can be sniffed by any eavesdropper. Not only eavesdropping, but cloning of the card is another significant problem that poses a privacy threat. An attacker can skim the information on a proximity card and clone it to use for his malicious purposes.RFID smart cards are now widely being used in credit cards,access system, transit system and many more such application. Tampering or malicious usage of data on aforementioned cards raises …

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Alternative Cooling Technologies For Telecommunication Data Centers: Air Cooling And Rear Door Heat Exchangers, Venkata Naga Poornima Mynampati Jan 2010

Alternative Cooling Technologies For Telecommunication Data Centers: Air Cooling And Rear Door Heat Exchangers, Venkata Naga Poornima Mynampati

Mechanical and Aerospace Engineering Theses - Archive

Telecommunication industry is currently emphasizing to a miniaturization and convergence. The need for smaller, smarter and faster devices is leading drastic increment in power density and accordingly, thermal management of such devices has become a challenge. The heat generated by the devices has to be dissipated in order to ensure proper and efficient functioning of the electronics. Electronics cooling ranges from device level to the room level cooling. Data Center is a facility (room) consisting of servers used for managing and transferring data or information. The thermal management of this facility is challenging due to the huge decrease in floor …

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Selective Cross Correlation In Passive Timing Analysis Attacks Against Low-Latency Mixes, Titus Abraham Jan 2010

Selective Cross Correlation In Passive Timing Analysis Attacks Against Low-Latency Mixes, Titus Abraham

Computer Science and Engineering Theses - Archive

A mix is a communication proxy that hides the relationship between incoming and outgoing messages. Routing traffic through a path of mixes is a powerful tool for providing privacy. When mixes are used for interactive communication, such as VoIP and web browsing, attackers can undermine user privacy by observing timing information along the path. Mixes can prevent these attacks by inserting dummy packets (cover traffic) to obfuscate timing information in each stream. Two recently proposed defenses, defensive dropping and adaptive padding, enhance cover traffic by ensuring that timing information seen at the sender is very different from that seen at …

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Towards Modeling The Behavior Of Physical Intruders In A Region Monitored By A Wireless Sensor Network, Pranav Krishnamoorthy Jan 2010

Towards Modeling The Behavior Of Physical Intruders In A Region Monitored By A Wireless Sensor Network, Pranav Krishnamoorthy

Computer Science and Engineering Theses - Archive

A priority task for homeland security is the coverage of large spans of open border that cannot be continuously physically monitored for intrusion. Low-cost monitoring solutions based on wireless sensor networks have been identified as an effective means to perform perimeter monitoring. An ad-hoc wireless sensor network scattered near a border could be used to perform surveillance over a large area with relatively little human intervention. Determining the effectiveness of such an autonomous network in detecting and thwarting an intelligent intruder is a difficult task. We propose a model for an intelligent attacker that attempts to find a detection-free path …

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Detecting Medication Consumption Patterns In Assistive Environments, Jyothi K. Vinjumur Jan 2010

Detecting Medication Consumption Patterns In Assistive Environments, Jyothi K. Vinjumur

Computer Science and Engineering Theses - Archive

One of the issues in healthcare systems or medical information systems is the reduction of medical errors to ensure patient safety. Our approach is to develop a cyber physical system which applies different RFID tags to monitor medicine consumption and its impact in an assistive environment. This approach talks about detecting the medication intake pattern in an assistive environment and implements an application oriented experimental research which tracks the drug consumption pattern using RFID readers and tags, motion sensors, a wireless sensor mote and a weight sensor. In this approach, an energy efficient technique by using multiple sensor devices which …

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High Performance Real-Time Embedded Systems: Design And Implementation Of Road Surface Analyzer System, Jareer Hamzah Ali Abdel Qader Jan 2010

High Performance Real-Time Embedded Systems: Design And Implementation Of Road Surface Analyzer System, Jareer Hamzah Ali Abdel Qader

Computer Science and Engineering Dissertations - Archive

Multi-core processors are becoming main components for many embedded systems. Designing such embedded systems is a complex task, since developers must deal with a number of issues such as multi-threading and optimal use of parallel processing. Multi-core processors can provide benefits to embedded applications in terms of performance improvement and power utilization. Problems related to real-time embedded systems in terms of designing, modeling, simulating, and implementing both hardware and software parts of embedded systems will be researched and discussed in this work. This research investigates and establishes the necessary steps to design, analyze, and implement a real-time embedded multi-core application. …

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Improving Privacy And Performance In Anonymous Communications, Nayantara Mallesh Jan 2010

Improving Privacy And Performance In Anonymous Communications, Nayantara Mallesh

Computer Science and Engineering Dissertations - Archive

Anonymous communications systems provide an important privacy service by keeping passive eavesdroppers from linking communicating parties. However, an attacker can use long-term statistical analysis of traffic sent to and from such a system to link senders with their receivers. While it is important to protect anonymous systems against such attacks, it is also important to ensure they provide good performance. In this thesis, we aim to make contributions to both these areas.In the statistical disclosure attack (SDA), an eavesdropper isolates his attack against a single user, whom we call Alice, with the aim of exposing her set of contacts. To …

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Adaptive Pain Management Decision Support System, Ching-Feng Lin Jan 2010

Adaptive Pain Management Decision Support System, Ching-Feng Lin

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Pain management is an international health issue. The Eugene McDermott Center for Pain Management at the University of Texas Southwestern MedicalCenter at Dallas conducts a two-stage interdisciplinary pain management program that considers a wide variety of treatments. Prior to treatment (stage 1), an evaluation records the patient's pain characteristics, medical history and related health parameters. A treatment regime is then determined. At the midpoint of their program (stage 2), an evaluation is conducted to determine if an adjustment in the treatment should be made. A final evaluation is conducted at the end of the program to assess final outcomes. The …

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Mathematical Modeling For Phagocyte Transmigration And Reverse Engineering, Min Gon Kang Jan 2010

Mathematical Modeling For Phagocyte Transmigration And Reverse Engineering, Min Gon Kang

Computer Science and Engineering Theses - Archive

Computational modeling and simulation have been used as an important tool to analyze the behavior of a complex biology system. Typically, the biology system is a complex non-linear system where a large number of components are involved. One of the major obstacles in computational modeling and simulation is to determine a large number of parameters in the mathematical equations representing biological properties of the system.To tackle this problem, we have developed a global optimization method, called Discrete Selection Levenberg-Marquardt (DSLM), for parameter estimation. The method uses a non-linear least square approach to approximate the solution of over-determined systems. For fast …

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A Novel Architecture For Mobility Enabled Video Conferencing In Next Generation Wireless Networks, Avinash Narayan Jan 2010

A Novel Architecture For Mobility Enabled Video Conferencing In Next Generation Wireless Networks, Avinash Narayan

Computer Science and Engineering Theses - Archive

The Heterogeneous nature of next generation networks requires architecture and technologies that have an intrinsic support for diversity. The plethora of existing wireless access technologies will soon be connected to Internet in the wave of "Internet of Things". We have learnt from many endeavors that no single technology exists that is ubiquitous and connects everything. In Cellular service, aside from the geographic coverage limitation, the major deficiency is lack of complete coverage inside buildings (offices, healthcare facilities, malls, and the like). Once we are inside many public buildings, cellular coverage is blocked by RF opaque walls, but may have strong …

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Position Sensorless Control Of A Magnetically Levitated (Maglev) System, Esteban Ricardo Noboa Jan 2010

Position Sensorless Control Of A Magnetically Levitated (Maglev) System, Esteban Ricardo Noboa

Electrical Engineering Dissertations - Archive

The main focus of this investigation is the development and implementation of a sensorless position estimation method and hysteresis position controller for a laboratory-based Maglev system. The proposed estimation method and controller are first validated through modeling and simulation. This sensorless scheme makes use of the maglev system's magnetic signature, namely, its inductance and requires only active phase current measurements. These measurements are then used along with the phase voltage equation to estimate position information that is in a one-to-one correspondence with the system's inductance. The theoretical aspects of the sensorless scheme are described. Finite element analysis (FEA) as well …

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Measuring Named Entity Similarity Through Wikipedia Category Hierarchies, Jared M. Ashman Jan 2010

Measuring Named Entity Similarity Through Wikipedia Category Hierarchies, Jared M. Ashman

Computer Science and Engineering Theses - Archive

Identifying the semantic similarity between named entities has many applications in NLP, including information extraction and retrieval, word sense disambiguation, text summarization and type classification. Similarity between named entities or terms is commonly determined using a taxonomy based approach, but the limited scalability of existing taxonomies has led recent research to use Wikipedia's encyclopedic knowledge base to find similarity or relatedness. These existing methods using Wikipedia have so far focused on relatedness, but are not as well suited to finding similarity. In this thesis, we evaluate methods for determining the semantic similarity between named entities by associating each named entity …

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Corporate Environmental Performance Rating Methodology, Arunapprakasini Sankaranarayanan Jan 2010

Corporate Environmental Performance Rating Methodology, Arunapprakasini Sankaranarayanan

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Environmental issues are becoming increasingly important to all kinds of stakeholders and companies themselves, not only for cost avoidance due to regulations, laws, cleanup costs, litigations, controversies, etc, but to improve their intrinsic ethical worth as a company for better environmental sustainability. Off late, companies are increasingly investing in environmental initiatives for cost savings and to generate profits as well. However, since no clear definition of greenness exists, companies are finding it difficult to measure environmental performance as an internal and external benchmark and hence a sound performance measurement system with formal guidelines is yet to be in place. What …

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Fault Detection And Optimal Treatment Of The Permanent Magnet Synchronous Machine Using Field Reconstruction Method, Amir Khoobroo Jan 2010

Fault Detection And Optimal Treatment Of The Permanent Magnet Synchronous Machine Using Field Reconstruction Method, Amir Khoobroo

Electrical Engineering Dissertations - Archive

Permanent magnet synchronous machines (PMSM) are used extensively in industrial applications due to their relatively high power density, high efficiency, negligible rotor losses, maintenance free operation, and ease of control. Fault tolerance has become a design criterion for adjustable speed motor drives (ASMD) which are used in high impact applications. In simple terms, a fault tolerant ASMD is expected to continue its intended function in the event of a failure compliment to its remaining components. A wide variety of the research has been done on the techniques of fault detection. Most of these researches focus solely on the fault detection …

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Development Of Su-8 And Pdms Miniatured Boats And Flotillas, Hao Li Jan 2010

Development Of Su-8 And Pdms Miniatured Boats And Flotillas, Hao Li

Electrical Engineering Dissertations - Archive

In this work, we developed miniaturized SU-8 and PDMS miniaturized boats and flotillas, and explored their designs, fabrication, actuation, motions and driving mechanisms. Like large-scale boats and flotillas, these miniaturized boat and flotillas can be potentially applied to transport designed targets to desired locations in small fluidic systems. They may also be employed as mixers, rotators and so on. We first develop a SU-8 boat, and studied its design, fabrication, actuation and motions. In three types of tests conducted on water free surfaces of different heights in a 30-cm-long channel, the microboat had a speed in the order of 0.1 …

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Light Trapping And Absorption Enhancement For High Performance Solar Cells And Infrared Photodetectors, Li Chen Jan 2010

Light Trapping And Absorption Enhancement For High Performance Solar Cells And Infrared Photodetectors, Li Chen

Electrical Engineering Dissertations - Archive

This dissertation presents the work on light trapping and absorption enhancement in solar cells and infrared photodetectors. Hemispherical microstructure based omni-directional anti reflection (Omni-AR) coating has been designed and developed for solar cells, based on rigorous coupled-wave analysis (RCWA) and convective coating process. Omni-AR coating enhances light absorption in solar cells, due to the reduced reflection on the structured solar cell surfaces, and the increased optical path length (OPL) inside the solar cells. Omni-AR coating has been demonstrated as a cost-effective light trapping approach for different material systems, with very low reflection and high transmission over a large range of …

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Real Time Condition Monitoring Of Chemical Batteries, Anahita Banaei Jan 2010

Real Time Condition Monitoring Of Chemical Batteries, Anahita Banaei

Electrical Engineering Dissertations - Archive

Li-Ion batteries are suitable rechargeable choices for electric and hybrid electric vehicle (EV/HEV) applications due to their relatively high level of energy and power density. One of the important issues in automotive batteries is to monitor their online state-of-charge (SOC) and state-of-health (SOH).Hence, development of an efficient method for monitoring their online state-of-charge (SOC) and state-of-health (SOH) is of high importance for vehicular applications. Open circuit voltage, as one parameter used for predicting the SOC of the battery, is not readily available during charge and discharge cycles. A wide variety of research has been done on SOC and SOH estimation …

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Multi-Wavelength All-Optical 2r Regeneration, Pallavi Govind Patki Jan 2010

Multi-Wavelength All-Optical 2r Regeneration, Pallavi Govind Patki

Electrical Engineering Dissertations - Archive

We experimentally demonstrate, for the first time to our knowledge, simultaneous all-optical 2R regeneration of multiple WDM channels. In the recent work [1], our group has proposed an all-optical 2R regeneration scheme capable of handling multiple WDM channels simultaneously. Our proposed multi-channel regenerator is a modified configuration of Mamyshev's 2R regenerator [2], in which a conventional highly-nonlinear-fiber (HNLF) is replaced by a novel dispersion-managed nonlinear medium. The proposed multi-channel regeneration scheme uses multiple concatenated dispersion-managed sections, where each dispersion-managed section contains a piece of HNLF and a periodic-group-delay device (PGDD). For the proof-of-principle demonstration of the regenerator we have built …

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Episodic Task Planning And Learning In Pervasive Environments, Yong Lin Jan 2010

Episodic Task Planning And Learning In Pervasive Environments, Yong Lin

Computer Science and Engineering Dissertations - Archive

During planning and control of autonomous robots in a pervasive environment designed to serve people, we will inevitably face the situations of needing to perform multiple complex tasks. Management and optimization of the execution of complex tasks involve the design of efficient approach and framework based on algorithm, artificial intelligence, machine learning, cognitive science, etc. In this dissertation, we have developed a new method for complex task planning of robots, so that they can improve the service for the elderly and the disabled. The word "episode" comes from Greek, which means "event", or "occurrence". Humans learn and plan from past …

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Adaptive Methods For Realistic And Intuitive Human-Robot Interaction, Jartuwat Rajruangrabin Jan 2010

Adaptive Methods For Realistic And Intuitive Human-Robot Interaction, Jartuwat Rajruangrabin

Electrical Engineering Dissertations - Archive

Due to the advancement in robotics and computer technology, having access to sophisticated robot hardware is becoming common. An increase in the number of robots allows one to achieve different kind of tasks by exploiting cooperation, such as: robot swarms, object manipulation using multiple degrees of freedom of different robots. It is quite challenging for the human operator to coordinate multiple robots to achieve a task in an efficient manner. The channels available to receive feedback information from the robot system can vary from simple encoder reading to video stream acquisition of the robot system performing tasks. It is important …

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Building Bayesian Network Based Expert Systems From Rules, Saravanan Thirumuruganathan Jan 2010

Building Bayesian Network Based Expert Systems From Rules, Saravanan Thirumuruganathan

Computer Science and Engineering Theses - Archive

Combining expert knowledge and user explanation with automated reasoning in domains with uncertain information poses significant challenges in terms of representation and reasoning mechanisms. In particular, reasoning structures understandable and usable by humans are often different from the ones for automated reasoning and data mining systems.Rules are a convenient and human understandable way to express domain knowledge and build expert systems. Adding certainty factors to these rules presents one way to deal with uncertainty in rule based expert systems. However such systems have limitations in accurately modeling the domain. Bayesian Network, on the other hand, is a probabilistic graphical model …

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Photonic Crystal Cavities For Spectrally-Selective Optoelectronic Devices, Hongjun Yang Jan 2010

Photonic Crystal Cavities For Spectrally-Selective Optoelectronic Devices, Hongjun Yang

Electrical Engineering Dissertations - Archive

Photonic crystal (PC) structures exhibit unconventional dispersion and refractive properties making possible hitherto not realizable optical and optoelectronic devices with high spectral selectivity. Functional PC devices (e.g., optical filters, reflectors, and photo detectors and light emitters) on both Si and III-V semiconductor material systems were fabricated via E-Beam lithography (EBL). The device layer can be further transferred onto foreign substrates such as glass or plastic (PET), using a low-cost "wet nanomembrane transfer technique" developed in this study.The broadband membrane reflectors (MR) based on Fano resonances in patterned silicon nanomembranes have been demonstrated. Resonance control of the reflectors was realized either …

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Embedded Sparse Representation For Image Classification, Jin Huang Jan 2010

Embedded Sparse Representation For Image Classification, Jin Huang

Computer Science and Engineering Theses - Archive

Image classification, such as face recognition and scene categorization, is an important research area in computer vision over the last decade. It has been successfully applied to many image analysis applications. Images usually have a large number of features, hence the dimensionality reduction methods are often employed before the subsequent classification to improve the classification results. A lot of methods have been proposed, including but not limited to PCA, ICA, LDA, and Bayesian Framework. Recently, compressive sensing and sparse learning have been widely studied and applied into computer vision research. Ma et al. suggested a new method called Sparse Representation …

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Evaluation Of Ferry Based Opportunistic Message Dissemination With Deterministic Inter Contact Times, Samreen Tahir Jan 2010

Evaluation Of Ferry Based Opportunistic Message Dissemination With Deterministic Inter Contact Times, Samreen Tahir

Computer Science and Engineering Theses - Archive

Opportunistic Networks are characterized by intermittent connectivity and volatile topology. In such a network scenario, traditional Mobile Ad hoc Network (MANET) routing protocols cannot work efficiently. Hence, a novel way of message forwarding is required that operates even when an end-to-end path between a source and destination pair may never exist. Delay Tolerant Networks (DTNs) are an approach to alleviate network partitioning by working on the `store-carry-forward' paradigm [4]. Opportunistic Networks encompass DTNs and typically involve mobile devices that exchange data by taking advantage of their proximity to other nodes. Nodes in opportunistic networks may be heterogeneous with respect to …

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Handling Periodic Signs In American Sign Language Using Synthetic Generation Of Periods, Himanshu Pahwa Jan 2010

Handling Periodic Signs In American Sign Language Using Synthetic Generation Of Periods, Himanshu Pahwa

Computer Science and Engineering Theses - Archive

American Sign Language (or ASL) is the dominant sign language of deaf people in United States and parts of Canada. 500,000 to 2 million people use ASL as their primary language in United States. ASL uses hands, face and body, with constantly changing movements and orientations. Since the language is based on gestures, not a printed alphabet, it gets difficult to know the associated meaning given a video. There are multimedia tools and dictionaries available to view a sign video for a given word but there are no dictionaries available which, given a sign video will respond with corresponding word. …

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A Human Motion Database: The Cognitive And Parametric Sampling Of Human Motion, Arnab Biswas Jan 2010

A Human Motion Database: The Cognitive And Parametric Sampling Of Human Motion, Arnab Biswas

Computer Science and Engineering Theses - Archive

Motion databases have a strong potential to guide progress in the field of machine recognition and motion-based animation. Existing databases either have a very loose structure that do not sample the domain according to any controlled methodology or too few action samples which limits their potential to quantitatively evaluate the performance of motion-based techniques. The controlled sampling of the motor domain in the database may lead investigators to identify the fundamental difficulties of motion cognition problems and allow the addressing of these issues in a more objective way. In this thesis, we describe the construction of our Human Motion Database …

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Neuro Adaptive Control For Aerospace And Distributed Systems, Abhijit Das Jan 2010

Neuro Adaptive Control For Aerospace And Distributed Systems, Abhijit Das

Electrical Engineering Dissertations - Archive

Nonlinear and adaptive control is generally considered one of the most effective techniques for stabilizing complex nonlinear systems, where linear control techniques may fail completely. Thousands of research papers are published on either theory or applications of nonlinear and adaptive control. But often one obvious question arises how to implement these techniques in real life model? The best answer that one can think of is to develop simple nonlinear control laws which are easy to implement. Moreover for controlling multi-agent systems, it is often required to distribute the control laws based on limited information available among the agents. This research …

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