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Dynamic Push And Pull Strategy Based On Data Interpolation For Web Sensor Networks, Rohita Mohan Aug 2007

Dynamic Push And Pull Strategy Based On Data Interpolation For Web Sensor Networks, Rohita Mohan

Computer Science and Engineering Theses - Archive

Sensor Web, a new trend has been developed recently to effectively network large scale deployed heterogeneous sensors with Internet to make sensor data discoverable, accessible and controllable via World Wide Web. Since sensor nodes are highly resource constrained, continuous back hauling of a large amount of data is not feasible. In this paper, we propose a dynamic push/pull service architecture where sensory quality is dynamically monitored and controlled. The architecture is implemented in a web proxy residing at the gateway of the network. As data is being pushed continuously from the network for effective sketching of the sensing field, interpolation …


A Framework For Improving The Performance Of Application Servers In Next Generation Networks (Ngns), Sumantra R. Kundu Aug 2007

A Framework For Improving The Performance Of Application Servers In Next Generation Networks (Ngns), Sumantra R. Kundu

Computer Science and Engineering Dissertations - Archive

Next generation networks (NGNs) such as IP Multimedia Subsystem (IMS) are completely built on the Internet Protocol (IP) suite. This has made IP the de facto standard for data networking, voice over IP (VoIP), and media rich applications such as streaming multimedia, ringtones, multi-player gaming, and high-definition video conferencing for remote interaction. A primary feature of such converged networks is that they use the same IP-based network for simultaneously delivering voice, video, and data. Such services are provided on application servers built using industry standard Advanced Telecom Computing Architecture (ATCA) based blade computing units with various flavors of commodity open …


A Robust Cooperative Localization System For A Heterogeneous Team Of Small Unmanned Ground Vehicles, Veera Jawahar Vibeeshanan Aug 2007

A Robust Cooperative Localization System For A Heterogeneous Team Of Small Unmanned Ground Vehicles, Veera Jawahar Vibeeshanan

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

This dissertation presents an organic approach to the cooperative localization problem by sequentially solving the problems of sensor calibration, multi-sensor fusion filtering, and cooperative localization. Successful navigation of unmanned ground vehicles requires accurate localization. Localization refers to the determination of the pose (position and orientation) of an unmanned ground vehicle with respect to a local or a global frame of reference. Cooperative localization is suited to multi-vehicle systems where vehicles with better accuracy in localization can assist those with poor accuracy through communication and relative pose sensing. A parametric modeling approach is presented for sensor calibration. Designed experiments are conducted …


Bookmarks 2007, Evelyn Barker Aug 2007

Bookmarks 2007, Evelyn Barker

Information Literacy Resources-Archive

No abstract provided.


Optimization Of Coupling From A Sub-Wavelength Metal Nanoaperture To A Gaussian Mode, Muthiah Annamalai Aug 2007

Optimization Of Coupling From A Sub-Wavelength Metal Nanoaperture To A Gaussian Mode, Muthiah Annamalai

Electrical Engineering Theses - Archive

We model the surface resonance effects in a 1D-array of corrugations on a metal-dielectric film with a sub-wavelength nanoaperture, following the earlier work by Moreno et-al [Moreno:2003]. We are interested in computing the coupling of the highly-directional light field emerging from the metal nanoaperture to the lowest-order Gaussian mode. We follow the approach by Vasilyev [Vasilyev:2005], to compute the coupling to a fundamental Gaussian mode. We have developed an optimization routine to compute the field emission patterns from a metal nanoaperture, resonant wavelength and transmission coupling to fundamental Gaussian mode for various geometrical parameters of the metal nanoastructure. We optimize …


Capacity Estimation Of Two-Sided Type C Weaves On Freeway, Phong Thanh Vo Jul 2007

Capacity Estimation Of Two-Sided Type C Weaves On Freeway, Phong Thanh Vo

Civil Engineering Dissertations - Archive

A weaving section is a common design on major highway facilities that has been an interest to researchers for years. Weaving areas are characterized by frequent lane changes, which significantly reduce the capacity of the freeway system. The 2000 Highway Capacity Manual (HCM) defined weaving capacity as "any combination of flows that causes the density to reach the LOS E/F boundary condition of 43 pcpmpl for freeways" based on configuration, number of lanes in the weaving section, free-flow speed, length of the weave, and volume ratio (VR). However, no research has been focused on the two-sided type C weaves, which …


Development Of Quality-Aware Video Systems And Nmr Spectrum Registration, Basavaraj Hiremath Jul 2007

Development Of Quality-Aware Video Systems And Nmr Spectrum Registration, Basavaraj Hiremath

Electrical Engineering Theses - Archive

The work introduces a novel concept of Quality-Aware Video (QAV) System and demonstrates its successful implementation. During the course, it develops algorithms for reduced reference video quality assessment and for data hiding. The idea here is to extract quality defining features of the video sequence and embed them in the original video without causing any perceptual changes to obtain QAV. Such a QAV can then be exposed to distortions and adverse attacks that affect the perceptual quality of the video. At the receiving end, the algorithm extracts the quality features of the distorted video, decode the original video quality features, …


Modeling Isotropic Organs Using Beam Models For The Haptic Simulation Of Blunt Dissections Of Bile Duct, Vishal Dalmiya Jul 2007

Modeling Isotropic Organs Using Beam Models For The Haptic Simulation Of Blunt Dissections Of Bile Duct, Vishal Dalmiya

Electrical Engineering Theses - Archive

Haptic modeling of organs using existing approaches is still not realistic and/or real time. We propose and develop the mathematical foundation of a new approach to modeling organs using beams. Beams are well known entities in Civil and Structural engineering. We develop their mathematical properties in the context of organ characteristics. The real time advantage arises from the fact that a single beam implementation eliminates hundreds, if not thousands of mass springs from the traditional mass spring models and, thousands of polygons from the finite element method (FEM). Even more importantly, our derivation works for both large and small deflections. …


Detection And Opportunistic Spectrum Access In Sensor Networks, Hung Dinh Ly Jul 2007

Detection And Opportunistic Spectrum Access In Sensor Networks, Hung Dinh Ly

Electrical Engineering Theses - Archive

This thesis examines target detection problems in Radar Sensor Networks (RSN) and opportunistic spectrum access problem in Cognitive Sensor Networks (CSN). First, studies on the Space-Time Adaptive Processing (STAP) and radar waveform design are provided. Investigation into the target detection performance gain of RSN when STAP and radar waveform design are combined in RSN is then performed. Studies in this thesis show that detection performance of RSN using our proposal is superior to that of a single radar system using STAP only. To further studies on target detection, the multi-target detection problem in RSN is also examined. Signal, interference, and …


Dynamic Chracteristics And Stability Analysis Of Muncipal Solid Waste In Bioreactor Landfills, Mohamed Adil Haque Jul 2007

Dynamic Chracteristics And Stability Analysis Of Muncipal Solid Waste In Bioreactor Landfills, Mohamed Adil Haque

Civil Engineering Dissertations - Archive

Bioreactor landfills are operated to enhance refuse decomposition, gas production, and waste stabilization. The major aspect of bioreactor landfill operation is the recirculation of generated leachate back through the refuse mass. Due to the accelerated decomposition and settlement of solid waste, bioreactor landfills are gaining popularity as an alternative to the conventional landfill designed under Subtitle D regulations. However, recirculation of leachate or addition of water to accelerate the waste decomposition changes the biodegradation and geotechnical characteristics of waste mass. Our understanding of changes in engineering characteristics of solid waste with accelerated decomposition is limited. There is a need to …


Game Theoretical Data Replication Techniques For Large-Scale Autonomous Distributed Computing Systems, Samee Ullah Khan Jul 2007

Game Theoretical Data Replication Techniques For Large-Scale Autonomous Distributed Computing Systems, Samee Ullah Khan

Computer Science and Engineering Dissertations - Archive

Data replication in geographically dispersed servers is an essential technique for reducing the user perceived access time in large-scale distributed computing systems. A majority of the conventional replica placement techniques lack scalability and solution quality. To counteract such issues, this thesis proposes a game theoretical replica placement framework, in which autonomous agents compete for the allocation or reallocation of replicas onto their representative servers in a self-managed fashion. Naturally, each agent's goal is to maximize its own benefit. However, the framework is designed to suppress individualism and to ensure system-wide optimization. Using this framework as an environment, several cooperative and …


Wireless Sensor Network Lifetime Analysis And Energy Efficient Techniques, Haining Shu Jul 2007

Wireless Sensor Network Lifetime Analysis And Energy Efficient Techniques, Haining Shu

Electrical Engineering Dissertations - Archive

Wireless microsensor networks is one of the most important technologies for the 21st century. In distributed sensor networks energy-aware techniques are used to reduce energy consumption. Various sensor network applications have taken energy efficiency into consideration. This thesis report focuses on a new approach based on fuzzy logic systems to analyze the lifetime of a wireless sensor network. It demonstrates that a type-2 fuzzy membership function (MF), i.e., a Gaussian MF with uncertain standard deviation (std) is most appropriate to model a single node lifetime in wireless sensor networks. This research studies two basic sensor placement schemes: square-grid and hex-grid. …


Power Control And Multi-Target Identification In Cognitive Wireless Networks, Hong-Sam Thi Le Jul 2007

Power Control And Multi-Target Identification In Cognitive Wireless Networks, Hong-Sam Thi Le

Electrical Engineering Theses - Archive

Recent research results have shown that cognitive wireless networks (CWN) have the potential to alleviate spectrum scarcity problem resulting from current policies for radio resource allocation management and dramatically improve the overall performance of communication systems. Unlike conventional wireless networks, which lack the flexibility and adaptation in their operations, CWNs exploit cognitive radio technology which provides cognitive wireless devices with the ability to sense the situation, adapt to the environment and take appropriate actions correspondingly. There have been many challenges in building a fully functional CWN. New developments and approaches need to be proposed to allow radio users to share …


Commencement Program 2007 May, University Of Texas At Arlington: College Of Science, The University Of Texas At Arlington May 2007

Commencement Program 2007 May, University Of Texas At Arlington: College Of Science, The University Of Texas At Arlington

Commencement Programs, Photos, and Video

No abstract provided.


Commencement Program 2007 May, University Of Texas At Arlington: College Of Engineering, The University Of Texas At Arlington May 2007

Commencement Program 2007 May, University Of Texas At Arlington: College Of Engineering, The University Of Texas At Arlington

Commencement Programs, Photos, and Video

No abstract provided.


Commencement Program 2007 May, University Of Texas At Arlington, The University Of Texas At Arlington May 2007

Commencement Program 2007 May, University Of Texas At Arlington, The University Of Texas At Arlington

Commencement Programs, Photos, and Video

No abstract provided.


Synthesis And Characterization Of Polythiophene Derivatives, Xin Chen May 2007

Synthesis And Characterization Of Polythiophene Derivatives, Xin Chen

Material Science and Engineering Dissertations - Archive

In Chapter 1, the history of conducting polymers, especially polythiophene and its derivatives, was briefly reviewed. Different approaches of structural modifications to afford small bandgap polythiophene derivatives were discussed. The emergence of metal-containing polymers (metallopolymers) as functional materials has attracted tremendous attention around the world. Introducing metals into thiophene-based oligomers and polymers, whether the backbone or the side chain of the p-conjugated framework, the electronic, optical, or magnetic properties of the material are expected to by significantly affected by metals through various mechanisms. Synthesis methods to prepare poly(thienylene vinylene) were also briefly reviewed in this chapter. In Chapter 2, the …


Autonomous And Cooperative Multi-Uav Guidance In Adversarial Environment, Ugur Zengin May 2007

Autonomous And Cooperative Multi-Uav Guidance In Adversarial Environment, Ugur Zengin

Mechanical and Aerospace Engineering Dissertations - Archive

The research presented in this dissertation is aimed at developing rule-based autonomous and cooperative guidance strategies for UAVs to perform missions such as path planning, target tracking and rendezvous while reducing their risk/threat exposure level, and avoiding threats and/or obstacles by utilizing measurement information provided by sensors. First, a mathematical formulation is developed to represent the area of operation that contains various types of threats, obstacles, restricted areas, in a single framework. Once constructed, there will be no need to distinguish between adversaries as the framework already contains the information on what needs to be avoided and the level of …


Sees - An Adaptive Multimodal User Interface For The Visually Impaired, Aparajit Saigal May 2007

Sees - An Adaptive Multimodal User Interface For The Visually Impaired, Aparajit Saigal

Computer Science and Engineering Theses - Archive

The enormous amount of electronic data present today can be a daunting task to access and process for a regular person, let alone someone with a disability. The World Wide Web and Electronic Mail have transformed the way we live. We are constantly become more dependent on this information, communication and commerce medium. The Speech Enabled Email System (SEES) is an alternate user interface that allows for the retrieval of emails and RSS feeds using speech. SEES can be accessed via a desktop application or through a telephony interface such as a regular phone-line or Voice over IP. This thesis …


Design, Analysis And Development Of A Morphable Wing Structure For Unmanned Aerial Vehicle Performance Augmentation, Abhijit Hiraman Supekar May 2007

Design, Analysis And Development Of A Morphable Wing Structure For Unmanned Aerial Vehicle Performance Augmentation, Abhijit Hiraman Supekar

Mechanical and Aerospace Engineering Theses - Archive

In this research, we propose mechanisms to continuously morph a wing from a lower aspect ratio to a higher and to further extremities of a gull and an inverted-gull configuration. The mechanism comprises of a linear actuator for the extension of the wing and the servo motors to obtain the gull and inverted gull configurations. The initial design and preliminary finite element representation using 3D-beams and plates in ANSYS Classic were the benchmarks to proceed for the detailed structural analysis of the complete wing in ANSYS Workbench. An elliptical pressure distribution at the quarter cord is assumed for the linear …


Design And Implementation Of A Feedback Linearizing Controller And Kalman Filter For A Magnetic Levitation System, John Andrew Henley May 2007

Design And Implementation Of A Feedback Linearizing Controller And Kalman Filter For A Magnetic Levitation System, John Andrew Henley

Mechanical and Aerospace Engineering Theses - Archive

The principal investigation undertaken in this research is the development and subsequent implementation of a feedback linearizing nonlinear controller and extended Kalman filter for a laboratory-based Magnetic Levitation (Maglev) device. The Maglev hardware is both highly nonlinear and open-loop unstable in its dynamic response. The control and estimation scheme proposed in this work is first validated using an increasingly sophisticated level of simulations. The control and estimation algorithm had the sensor noise identified using hardware data. Then, the plant noise covariance is tuned using both on-line and off-line hardware data. Additionally, the output of the nonlinear controller is then mapped …


Experimental Study Of Laminated Composite Tubes Under Bending, Puneet Saggar May 2007

Experimental Study Of Laminated Composite Tubes Under Bending, Puneet Saggar

Material Science and Engineering Theses - Archive

Bending stiffness of laminated composite tubes was determined experimentally using four-point bending test. The experimental results were compared with the results obtained by the laminated plate and smear property approaches. The results indicate that experimental values are closer to prediction of the laminated plate approach compared to smear property approach. Effects of tube radius and stacking sequence and fiber orientation of the walled thickness laminate on bending stiffness and strength of composite tubes were studied. Fracture analysis was conducted to investigate the failure process of the tube. Both techniques of x-ray radiography and optical microscopy were used in this study. …


A Generic Stability And Control Tool For Flight Vehicle Conceptual Design: Aeromech Software Development, Gary John Coleman May 2007

A Generic Stability And Control Tool For Flight Vehicle Conceptual Design: Aeromech Software Development, Gary John Coleman

Mechanical and Aerospace Engineering Theses - Archive

During the conceptual design (CD) phase, various solution concepts must, and should, be explored to select the best flight vehicle size and configuration in order to meet the mission requirements. As the aerospace industry advances novel aerospace flight vehicle configurations promising larger operational performance and overall efficiency, demanding integrated flight vehicles like the flying wing configuration (FWC) or blending wing body (BWB) are under investigation. Some of these novel configurations rely on novel control effectors (CE) and complex flight control systems in order to obtain the desired performance objectives. Clearly, stability and control plays an important roll in the design …


Experimental Studies To Address Strengths Of Limestone Cores, Sulfate Heave Problems In Limestone Cores And Tunnel Lining, Vivekananda Chikyala May 2007

Experimental Studies To Address Strengths Of Limestone Cores, Sulfate Heave Problems In Limestone Cores And Tunnel Lining, Vivekananda Chikyala

Civil Engineering Theses - Archive

Sulfate induced heave is a common scenario in tunnels located on sedimentary rocks containing Pyrites. Pyrite oxidation produces Gypsum which is a major source of natural sulfates. DART NC -1B tunnel is located in Dallas, north Texas. Dallas is located on sedimentary rocks with high Pyrite content and has a history of sulfate induced heave problems in several projects. In spring 2005 & 2006, the shotcrete liner in DART NC-1B tunnel showed cracking associated with water leaks. Considering the local geology and the history of the tunnel, researchers at The University of Texas at Arlington (UTA) suspected probable occurrence of …


Performance Studies On Rigid Pavement Sections Built On Stabilized Sulfate Soils, Deepti Vasudev May 2007

Performance Studies On Rigid Pavement Sections Built On Stabilized Sulfate Soils, Deepti Vasudev

Civil Engineering Theses - Archive

Soils of Southeast Arlington are highly expansive and rich in sulfates. They undergo sulfate induced heaving when traditional calcium based stabilizers are used for soil stabilization (Puppala et al. 1998). Traditional stabilizers do not provide effective solution since they are known to induce heaving, termed in the literature as sulfate induced heaving (Hunter, 1988). Both swelling and softening of these soils rich in sulfates induce considerable damage to overlying pavement infrastructure. Typically, high sulfate soils treated with calcium based stabilizers form ettringite mineral. Ettringite undergoes heaving when hydrated (Hunter, 1988; Puppala et al. 2001). Since this sulfate-induced heave is caused …


Tissue And Vascular Oxygenation Dynamics Determined By Optical Approaches And Mri, Mengna Xia May 2007

Tissue And Vascular Oxygenation Dynamics Determined By Optical Approaches And Mri, Mengna Xia

Bioengineering Dissertations - Archive

Tumor oxygenation is a crucial factor to determine the efficiency of non-surgery therapy, such as radiotherapy and chemotherapy. Therefore, various approaches have been applied to tumor in order to improve the tumor oxygen level. Breathing oxygenrich gas with normobaric or hyperbaric pressure has been demonstrated to overcome hypoxia, but with marginal success. Therefore, the outcome would be improved greatly, if the responsive tumors were identified a priori. Two non-invasive techniques were applied to monitor tumor oxygenation dynamics simultaneously when rats were exposed to hyperoxic gas intervention. 19F MRI provides tumor tissue oxygen tension (pO2) images, while Near Infrared Spectroscopy (NIRS) …


Effects Of A Debonding Flaw Size And Location On The Flexural Performance Of Cfrp Retrofitted Steel Sections, Sharad C. Choudhary May 2007

Effects Of A Debonding Flaw Size And Location On The Flexural Performance Of Cfrp Retrofitted Steel Sections, Sharad C. Choudhary

Civil Engineering Theses - Archive

In US there are several thousand steel bridges at present. Out of them many bridges are at various level of advance deteriorations due to many years of service life and environmental factors. These bridges cannot be fully replaced so retrofitting is the best choice .Earlier steel plates were used. With introduction of FRP in 1960.It is replacing the steel plates as they are lighter in weight and can be made stronger than steel. While installation of these FRP some kinds of Flaws are encountered. The variation of strength of carbon fiber reinforced laminate used for structural repair or strengthening containing …


Wireless Sensor Network Testbed: Measurement And Analysis, Rahul Pramod Sawant May 2007

Wireless Sensor Network Testbed: Measurement And Analysis, Rahul Pramod Sawant

Electrical Engineering Theses - Archive

Energy conservation is critical in Wireless Sensor Networks. Replacing or recharging batteries is not an option for sensors deployed in hostile environments. Generally communication electronics in the sensor utilizes most energy. This thesis studies the effect of changing the transmission power and baud rate on transmission distance. Using Shannon channel capacity formula and Log - Distance Path Loss Model, transmission distance is shown to be related to transmit power and baud rate. Extensive empirical readings are taken to confirm the above relation. The path loss exponent got as a result of data fitting is within the acceptable range for wireless …


Electromagnetically Actuated Devices For Optical Coherence Tomography Applications, Hans P. Hu May 2007

Electromagnetically Actuated Devices For Optical Coherence Tomography Applications, Hans P. Hu

Electrical Engineering Dissertations - Archive

A fast optical scanning device has always been desired for numerous applications such as biomedical imaging, optical communications, and variety of sensing and actuating applications. This dissertation presents a new scanning device operated using external magnetic field with low cost, high function versatility, low field strength, and low power consumption. The design architecture of this device shows its potential for in vivo application with an advantage that addresses the concern of safety. Materials properties are examined using alternating gradient magnetometer(AGM) to verify its performance. Pressure and temperature invariant fabrication processes are implemented to make this device without complicated equipments. The …


Discrete-Time Control Algorithms And Adaptive Intelligent Systems Designs, Asma Azmi Al-Tamimi May 2007

Discrete-Time Control Algorithms And Adaptive Intelligent Systems Designs, Asma Azmi Al-Tamimi

Electrical Engineering Dissertations - Archive

In this work, approximate dynamic programming (ADP) designs based on adaptive critic structures are developed to solve the discrete-time optimal control problems in which the state and action spaces are continuous. This work considers linear discrete-time systems as well as nonlinear discrete-time systems that are affine in the input. This research resulted in forward-in-time reinforcement learning algorithms that converge to the solution of the Generalized Algebraic Riccati Equation (GARE) for linear systems. For the nonlinear case, a forward-in-time reinforcement learning algorithm is presented that converges to the solution of the associated Hamilton-Jacobi Bellman equation (HJB). The results in the linear …