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Full-Text Articles in Physical Sciences and Mathematics

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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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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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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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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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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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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Mimic: An Active Covert Channel That Evades Regularity-Based Detection, Kush Kothari Jan 2010

Mimic: An Active Covert Channel That Evades Regularity-Based Detection, Kush Kothari

Computer Science and Engineering Theses - Archive

A covert timing channel is a hidden communication channel based on network timing that an attacker can use to sneak secrets out of a secure system. Active covert channels, in which the attacker uses a program to automatically generate innocuous traffic to use as a medium for embedding the covert channel, are especially problematic, as they allow the attacker to output large amounts of secret data. A promising technique for detecting covert timing channels focuses on using entropy-based tests. This technique can reliably detect known covert timing channels by using a combination of entropy (EN) and conditional entropy (CE) to …

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Target Tracking With Lucas-Kanade Optical Flow And Particle Filters Through Affine Transforms And Occlusion, Justin Graham Jan 2010

Target Tracking With Lucas-Kanade Optical Flow And Particle Filters Through Affine Transforms And Occlusion, Justin Graham

Computer Science and Engineering Theses - Archive

This paper investigates a hybrid approach derived from Lucas-Kanade optical flow tracking and particle filters that is capable of tracking objects through occlusion and affine transformations. This approach is inspired by aircraft sensor pod infrared and electro-optical tracking applications. For aircraft based sensors, it is important that a tracking system be able to track through rotations as the aircraft orbits a targeting area. It is also of use to handle cases where the target may be momentarily occluded due to other vehicles or obstacles in the area. The main focus of this investigation is to find a technique that performs …

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A Framework For Real-Time Fault Detection And Response In Multi-Agent Teams, Matthew B. Middleton Jan 2010

A Framework For Real-Time Fault Detection And Response In Multi-Agent Teams, Matthew B. Middleton

Computer Science and Engineering Theses - Archive

This thesis details the creation of a fault detection and response framework that can be applied to mobile multi-agent teams. This framework unites existing concepts of conditioned based maintenance and real-time machine diagnostics with a high-level matrix based discrete event command and control system that can respond to detected mechanical faults in agents in real-time. This allows for automatic corrective actions to be taken when an agent experiences failure if redundant resources are available to replace the failed unit or for the mission planner to be notified that the mission is no longer achievable given the operating conditions of the …

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Real Time Hardware And Software Systems For Micro Air Vehicle Flight Control Testing, Christopher Dale Mcmurrough Jan 2010

Real Time Hardware And Software Systems For Micro Air Vehicle Flight Control Testing, Christopher Dale Mcmurrough

Computer Science and Engineering Theses - Archive

The trend of increasing capabilities of micro scale electrical, mechanical, and computing systems is opening up the possibilities of new unmanned vehicle platforms. Both unmanned aerial and ground vehicles have traditionally been created from large conventional platforms such as automobiles, rotorcraft, and fixed wing aircraft. These conventional chassis designs are durable and proven, but the benefits of automating these types of platforms are limited by their inherent human-centric design. Many real-world applications would benefit greatly from vehicle classes designed with unconventional means such as biologically inspired locomotion. Micro air vehicles are a class of vehicles that have recently began moving …

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Fast Jamming Detection In Wireless Sensor Networks, Kartik Siddhabathula Jan 2010

Fast Jamming Detection In Wireless Sensor Networks, Kartik Siddhabathula

Computer Science and Engineering Theses - Archive

Non-dedicated medium of communication for Wireless Sensor Networks (WSN) makes them vulnerable to jamming attack where an adversary injects strong signal or noises to interfere with the transmission and thus block the channel. In applications such as border security, people are particularly interested in the areas where the channel is currently jammed. It is therefore crucial to be able to detect the jamming attacks as fast as possible. Existing studies have shown that the most effective indicator of jamming attacks is the packet delivery ratio (PDR). However, current PDR-based schemes use end-to-end packet delivery ratio, which requires one to observe …

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Fast And Energy-Efficient Technique For Jammed Region Mapping In Wireless Sensor Networks, Nabila Rahman Jan 2010

Fast And Energy-Efficient Technique For Jammed Region Mapping In Wireless Sensor Networks, Nabila Rahman

Computer Science and Engineering Theses - Archive

Wireless sensor networks (WSNs) have great practical importance for surveillance systems to perform monitoring by acquiring and sending information about intrusions into a secured area. Very little human intervention is required for WSNs, which is one of the most desirable features of them and thus making them a cheaper and safer alternative for securing large area such as international borders. Jamming attacks in WSNs can be applied to disrupt communications among the sensor nodes in the network by barring the reception of wireless signals of the sensor nodes' transceivers. Since it is difficult to prevent jamming attacks, detection and mapping …

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Microfacies Analysis Of The Jacksboro Limestone Member (Graham Formation, Virgilian, Pennsylvanian) In Jack County, Texas, Claudio Manuel Leyva Jan 2010

Microfacies Analysis Of The Jacksboro Limestone Member (Graham Formation, Virgilian, Pennsylvanian) In Jack County, Texas, Claudio Manuel Leyva

Earth & Environmental Sciences Theses - Archive

The Jacksboro Limestone is a member of the Graham Formation of the Virgilian (Upper Pennsylvanian) and is exposed only in and around the city of Jacksboro in central Jack County, Texas. The purposes of this investigation were to study the vertical and lateral microfacies changes that occur throughout the Jacksboro Limestone in its outcrop belt and to discuss its relationship as the basal regressive cycle in the Virgilian part of the Pennsylvanian, in particular: (1) describe and classify the primary limestone lithofacies on the basis of carbonate rock textures, (2) interpret, if possible, the depositional environment and physical energy of …

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Conditional Confidence Intervals Of Process Capability Indices Following Rejection Of Preliminary Tests, Jianchun Zhang Jan 2010

Conditional Confidence Intervals Of Process Capability Indices Following Rejection Of Preliminary Tests, Jianchun Zhang

Mathematics Dissertations - Archive

Finding an ordinary confidence interval of an unknown parameter is well known, but finding a conditional confidence interval following rejection of a preliminary test is not so noted, especially for finding a conditional confidence interval of the process capability indices Cp or Cpk following rejection of some preliminary tests. This dissertation will provide some basic theories and computational methods for finding such conditional confidence intervals of the two process capability indices. The most basic method used in this dissertation is the general method for finding a confidence interval of an unknown parameter. Numerical methods are also used for finding the …

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Event Recognition From Ambient Assistive Living Technologies, Eric William Becker Jan 2010

Event Recognition From Ambient Assistive Living Technologies, Eric William Becker

Computer Science and Engineering Dissertations - Archive

As the population ages and technology advances, a need exists for creating ambient intelligent systems to be placed within the home environment. Attitudes towards technology have been changing, and home monitoring is now considered a less expensive and desirable alternative. Ideally, such systems should be small, wireless, and take the minimum of effort and cost to install and place within the home. In order to detect human activity in an assistive environment, key questions about the construction and operation of the technology and methods needed to detect that activity. To that end, a computational framework has been created inside an …

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Advanced Software Testing Techniques Based On Combinatorial Design, Wenhua Wang Jan 2010

Advanced Software Testing Techniques Based On Combinatorial Design, Wenhua Wang

Computer Science and Engineering Dissertations - Archive

Combinatorial testing refers to a testing strategy that applies the principles of combinatorial design to the domain of software test generation. Given a system with k parameters, combinatorial testing requires all the combinations involving t out of k parameters be covered at least once, where t is typically much smaller than k. The key insight behind combinatorial testing is that while the behavior of a system may be affected by many parameters, most faults are caused by interactions involving only a small number of parameters. Empirical studies have shown that combinatorial testing can dramatically reduce the number of tests while …

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Information-Driven Data Gathering In Wireless Sensor Networks, Jing Wang Jan 2010

Information-Driven Data Gathering In Wireless Sensor Networks, Jing Wang

Computer Science and Engineering Dissertations - Archive

Since the advance of wireless technology enables the mass production of low-cost, small-sized sensor nodes, sensor nodes can be densely deployed in an area for high tolerance to node failure or to achieve better coverage statistically. The redundancy of sensor nodes results in the temporal and spatial correlation of sensory data, which motivates the information-driven data gathering approaches for wireless sensor networks (WSNs).Since existing approaches target at the sensory data that are already highly correlated with each other, little attention has been paid to the idea of changing the sampling schedules of the sensor nodes to reduce the correlation among …

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Combating Dos Attacks In Wireless Networks Using Lightweight Key Mangement Schemes, Qi Dong Jan 2010

Combating Dos Attacks In Wireless Networks Using Lightweight Key Mangement Schemes, Qi Dong

Computer Science and Engineering Dissertations - Archive

The unique features of wireless networks lead to many attractive applications in both military and civilian operations. Wireles networking devices usually use batteries as power supply, which requires all the operations to be as efficient as possible. Since the resources such as the battery energy and wireless communication channels are critical in wireless networks, the attacker my try to disable the system operation by launching denial of service (DoS) attacks. Specifically, the attacker prevents the system from working by using up or blocking the limited resources.This dissertation includes three studies on security mechanisms to combat DoS attacks using lightweight key …

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Electrowetting Of Ionic Liquids And Development Of An Electrowetting Based Tunable Rc Filter And Its Uses As An Analytical Detector, Yasith Sameera Nanayakkara Jan 2010

Electrowetting Of Ionic Liquids And Development Of An Electrowetting Based Tunable Rc Filter And Its Uses As An Analytical Detector, Yasith Sameera Nanayakkara

Chemistry & Biochemistry Dissertations - Archive

Wettability control of a liquid drop by an external electric field or "electrowet- ting" recently was the subject of special interest among researchers due to its util- ity for a variety of applications. Some of these include "electrowetting on dielectric (EWOD)" based digital microfluidic lab-on-a-chip devices, EWOD lenses and EWOD displays. In these EWOD based devices, water or aqueous electrolytes are used as the liquid medium. However, the use of water or aqueous electrolytes has several limitations and may reduce the efficiency as well as accuracy of these devices. Low thermal stability, evaporation, fouling and fixed phys- iochemical properties are …

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Enantiomeric Chromatographic Separations And Ionic Liquids In Gas Chromatography, Ke Huang Jan 2010

Enantiomeric Chromatographic Separations And Ionic Liquids In Gas Chromatography, Ke Huang

Chemistry & Biochemistry Dissertations - Archive

Due to the different therapeutic values of optical isomers, the production of enantiomerically pure drugs is of growing demand in pharmaceutical, biotechnology, and agrochemical industries. Today, gas chromatography (GC) and high performance liquid chromatography (HPLC) are the most prevalent analytical techniques for the enantiomeric separation of chiral molecules. Although the two techniques can have very different separation mechanisms, they are highly complementary to each other. Together, they can accomplish enantiomeric separations for large numbers of compounds of different functionalities. A great variety of chiral stationary phases (CSPs) have been developed over the years. However, since they are the heart of …

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2010 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie Jan 2010

2010 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie

Data Sets

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the photo point locations, aerial photos, and flight maps for the year 2010.

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Total Synthesis Of 2-Aminoimidazole Alkaloids From Leucetta And Clathrina Sponges, Panduka B. Koswatta Jan 2010

Total Synthesis Of 2-Aminoimidazole Alkaloids From Leucetta And Clathrina Sponges, Panduka B. Koswatta

Chemistry & Biochemistry Dissertations - Archive

Sponges of the major class, Calcarea can be found in nearly all marine habitats. Two Calcarea genera, Leucetta and Clathrina have found be rich with 2-aminoimidazole alkaloids. The first alkaloid of these groups was isolated in 1987 from a bright yellow sponge of the class Calcispongiae (calcarea) and Leucetta chagosensis dendy (Leucetta) collected near Na'ama in the Gulf of Eilat (Aqaba) in the Red Sea. The nomenclature for this whole series of compounds is based on the location of the initial source material. The first Chapter describes the isolation, biological activities, possible biosyntheses and total synthesis of these alkaloids. The …

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Reinforcement Learning Based Strategies For Adaptive Wireless Sensor Network Management, Kunalbhai Shah Jan 2010

Reinforcement Learning Based Strategies For Adaptive Wireless Sensor Network Management, Kunalbhai Shah

Computer Science and Engineering Dissertations - Archive

In wireless sensor networks (WSN), resource-constrained nodes are expected to operate in highly dynamic and often unattended environments. WSN applications need to cope with such dynamicity and uncertainty intrinsic in sensor networks, while simultaneously trying to achieve efficient resource utilization. A middleware framework with support for autonomous, adaptive and distributed sensor management, can simplify development of such WSN applications. We present a reinforcement learning based WSN middleware framework to enable autonomous and adaptive applications with support for efficient resource management. The uniqueness of our framework lies in using a bottom-up approach where each sensor node is responsible for its resource …

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