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2006

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Performance Analysis Of The Beacon Period Contraction Mechanism In Wimedia Mac For Uwb, Shenjin Sun Dec 2006

Performance Analysis Of The Beacon Period Contraction Mechanism In Wimedia Mac For Uwb, Shenjin Sun

Computer Science and Engineering Theses

The WiMedia MAC for UWB based WPANs is currently preferred among standards for wireless network since it requires non-infrastructure for ad hoc network, and also supports for Quality of Service (QoS). Without infrastructure, coordination of devices within radio range is achieved by the exchange of beacon frames, which is an overhead in WiMedia MAC, since no data transmission is allowed during Beacon Period (BP). In a dynamic network, devices might leave or join in, so beacon slots will be released or reoccupied with the changing of network. And BP contraction mechanism is aimed at reusing the released beacon slots in …


Miniature Optical Coherence Tomography Probe, Asif Rizwan Dec 2006

Miniature Optical Coherence Tomography Probe, Asif Rizwan

Bioengineering Theses

A piezo based optical scanner for high speed optical coherence tomography (OCT) has been developed. Design of the miniature probe has been optimized to take advantages of the high speed depth scanning that can be achieved with spectral domain OCT (SD-OCT) systems. Three prototype scanning probes were constructed and tested for OCT imaging. Movies and images of tissues are presented which were taken at frame rates ranging from 50~100fps. Data were acquired at 18000 A-lines per second at an effective integration time of 55us.


A Comprehensive Study Of The Effects Of Eeg Electrode Arrays On Mri Signal-To-Noise At 3t, Aman Ish Goyal Dec 2006

A Comprehensive Study Of The Effects Of Eeg Electrode Arrays On Mri Signal-To-Noise At 3t, Aman Ish Goyal

Bioengineering Theses

Simultaneous EEG-fMRI offers much potential for gaining complementary, noninvasive information about brain function. While much effort has been devoted to the compelling problem of removing ballistocardiogram and gradient artifacts from the EEG waveforms, less attention has been paid to the impact that increasing density of electrode arrays has on the MR images. Initial work reporting the effects of EEG caps and electrodes on the MR image has been site specific, using customized EEG equipment that those research groups built in-house. Therefore these results are hard to generalize to other laboratory environments. A monotonic decrease in SNR of the images has …


Ca-Ole- A Collaborative And Adaptive Online Learning Environment, Paola Gomez Dec 2006

Ca-Ole- A Collaborative And Adaptive Online Learning Environment, Paola Gomez

Computer Science and Engineering Theses

Demand for online learning environments has grown in the past few years, and schools have been offering more distance courses to their students. Designing adequate online learning environments is considerably more challenging than conventional Face-To-Face courses; therefore traditional methods can not be used. This thesis proposes the creation of a Collaborative and Adaptive Online Learning Environment (CA-OLE) that provides a structure where instructors can combine their lesson materials with an adaptive system and collaborative tools. CA-OLE innovative approach consists of an adaptive framework that changes the way the learning materials prepared by instructors are presented to the students depending on …


Fiber Based Non-Linear Excitation Fluorescence Microscopy, Priyanka Amrita Jillella Dec 2006

Fiber Based Non-Linear Excitation Fluorescence Microscopy, Priyanka Amrita Jillella

Bioengineering Theses

Non-linear excitation fluorescence microscopy is a high resolution, non-invasive biological imaging technique capable of imaging both in vitro and in vivo at the depths of several hundred microns. The goal of the thesis work is to contribute towards a fiber based non-linear excitation fluorescence microscopy system that we plan to build for our lab, which would later on be integrated with the OCT imaging setup and the DIC microscope. This thesis work involves filling in the key components in the microscopy system. These key components are; femtosecond pulse diagnosis, study of dispersion in optical media, dispersion free femtosecond pulse delivery …


Runtime Optimization And Load Shedding In Mavstream: Design And Implementation, Balakumar Kendai Dec 2006

Runtime Optimization And Load Shedding In Mavstream: Design And Implementation, Balakumar Kendai

Computer Science and Engineering Theses

In data stream processing systems Quality of Service (or QoS) is extremely important. The system should try its best to meet the QoS requirements specified by a user. On account of this difference, unlike in a database management system, a query cannot be optimized once and executed. It has been shown that different scheduling strategies are useful in trading tuple latency requirements with memory and throughput requirements. In addition, data stream processing systems may experience significant fluctuations in input rates. In order to meet the QoS requirements of data stream processing, a runtime optimizer equipped with several scheduling and load …


Spectroscopic Characterization Of Biliary Tract Tissues In-Vivo To Assist Laparoscopic Cholecystectomy, Sarita Kommera Dec 2006

Spectroscopic Characterization Of Biliary Tract Tissues In-Vivo To Assist Laparoscopic Cholecystectomy, Sarita Kommera

Bioengineering Theses

Laparoscopic Cholecystectomy is a surgical method for removal of gallbladder when it is diseased with gall stones. Almost 750,000 people are affected with this disease annually in USA. Gall bladder is removed by placing an incision on the cystic duct. This duct is totally embedded in fat (which is a few mm thick) in most of the cases and it becomes a huge problem decreasing the visual capability of the surgeon to distinctly locate the duct. Near Infrared Spectroscopy (NIRS) can solve the fuzziness as it penetrates in a few mm thick tissues. NIRS is one of the simplest techniques …


Analyzing Differences In Color Variation Sensitivity Between Experts And Novices To Find A Differentiating Process In Pigmented Skin Lesion Diagnosis, Yu-Chin Chai Dec 2006

Analyzing Differences In Color Variation Sensitivity Between Experts And Novices To Find A Differentiating Process In Pigmented Skin Lesion Diagnosis, Yu-Chin Chai

Computer Science and Engineering Theses

Fatal skin lesions such as melanomas appear as having high color variation to experts but often as having low variation to novices. This thesis investigated if it is possible to find a function representing an expert's color variation sensitivity to skin lesions without explicitly requiring them to provide a diagnosis. Various pigmented skin images with either normal pigmentation or with diseased lesions were evaluated by experts and novices. To determine the best color space for lesion differentiation, an optimization process based on parametric color dimensions in a RGB color space was used to find the parameters of a color transformation …


Compensation Of Photobleached Images For A Cell Dynamics System, Sowmya Gopinath Dec 2006

Compensation Of Photobleached Images For A Cell Dynamics System, Sowmya Gopinath

Computer Science and Engineering Theses

Progress in the field of medicine attributes to the discoveries in biology that require an extensive knowledge of cell dynamics. Intracellular Cell Dynamics Analysis System (ICellDAS) is a web based tool aimed at automating sub cellular particle motion estimation, tracking and mobility analysis. The purpose of this tool is to develop a better understanding of specific biology problems by visualizing biological data. For reliable analysis as well as visualization of cell dynamics, it is essential that the acquired images reflect the exact information of the specimen. The goal of the thesis is to design an interface for the ICellDAS project …


Experimental Investigation Of Shear Capacity Of Precast Reinforced Concrete Box Culverts, Jarrod Clinton Burns Dec 2006

Experimental Investigation Of Shear Capacity Of Precast Reinforced Concrete Box Culverts, Jarrod Clinton Burns

Civil Engineering Theses

This study presents the experimental investigation of the shear capacity of four precast rinforced concrete box culverts. Each culvert was subjected to a monotomically increasing load through a 20-in x 10-in load plate, designed to simulate a standard HS 20-44 wheel footprint. Each box was instrumented with the following: strain gages, load cell, high-resolution laser sensor, data acquisition hardware and software, and laptop computer. The tests were conducted on 1.22 m x 1.22 m x 1.22 m (4 ft x 4 ft x 4 ft) box culverts, with load being applied at the free spigot end. The location of the …


Personalizing (Re-Ranking) Web Search Results Using Information Present On A Social Network, Sushruth Puttaswamy Dec 2006

Personalizing (Re-Ranking) Web Search Results Using Information Present On A Social Network, Sushruth Puttaswamy

Computer Science and Engineering Theses

We describe a social search engine paradigm which can be built on top of a classic search engine (e.g. Google, Yahoo, etc.) and a social information network (such as FriendSter). In this thesis, the objective was to design algorithms and develop methods to efficiently combine information available in the underlying systems (Search Engine & Social Information Network) to better satisfy the search needs of a user. We are interested on how to efficiently employ social information to re-order a list of URLs retrieved by querying a search engine. The objective was to re-order the list of URLs in a way …


Novel Intraocular Drug Delivery System For The Prevention Of Posterior Capsule Opacification, Brett Thomes Dec 2006

Novel Intraocular Drug Delivery System For The Prevention Of Posterior Capsule Opacification, Brett Thomes

Bioengineering Dissertations

Posterior capsule opacification (PCO) is a major complication associated with the implantation of intraocular lens (IOLs). Evidence suggests that PCO formation is caused by abnormal lens epithelial cell (LEC) migration/proliferation. We hypothesize that pharmacologic agents must target inflammatory cells in addition to LECs to inhibit PCO formation. To successfully target both inflammatory cells and LECs, a novel intraocular drug delivery system (DDS) was developed for implantation in the lens capsular bag. Such a system permits direct delivery of anti-inflammatory and anti-proliferative drugs in the lens capsule for extended periods of time resulting in reduced PCO formation. A lubricious polyurethane coating …


Tracing And Replay Of Real-Time Concurrent Programs In Vxworks, Daxa Keshavji Patel Dec 2006

Tracing And Replay Of Real-Time Concurrent Programs In Vxworks, Daxa Keshavji Patel

Computer Science and Engineering Theses

Real-time concurrent programs are difficult to analyze, debug and test because of the existence of race conditions. In particular, cyclic debugging requires the ability to reproduce a failed execution. That is, when a failure is observed during a test run, it is often necessary to reproduce the test run as an effort to locate the bug that has caused the failure. However because of the variations in thread scheduling and signal latency, a real-time concurrent execution may not be reproduced simply by re-executing the program under test. In this thesis, we describe a language-based framework for tracing and replay of …


End-To-End Optimal Algorithms For Traffic Engineering, Failure Detection And Recovery In Connectionless Networks, Sukruth Srikantha Dec 2006

End-To-End Optimal Algorithms For Traffic Engineering, Failure Detection And Recovery In Connectionless Networks, Sukruth Srikantha

Computer Science and Engineering Theses

In this thesis we propose a novel scheme to achieve intra-domain Traffic Engineering (TE), Failure Detection and Recovery (FR) in connectionless networks. This scheme addresses rate adaptation, load balancing and stability issues of the OSPF protocol namely, network convergence times and route flapping. With the current default settings of the OSPF parameters, the network takes several tens of seconds to recover from a failure. The main component in this delay is the time required to detect the failure using the Hello protocol. Route flap is another undesirable phenomenon and needs to be eliminated to achieve greater stability and robustness in …


Adaptive Load Balancing And Change Visualization For Webvigil, Subramanian Chelladurai Hari Hara Dec 2006

Adaptive Load Balancing And Change Visualization For Webvigil, Subramanian Chelladurai Hari Hara

Computer Science and Engineering Theses

There is a need for selective monitoring, the contents of web pages. Periodical visit for understanding changes to a web page is both inefficient and time consuming. WebVigiL is a system developed for automating the change detection and timely notification of HTML/XML pages based on user specified changes of interest. User interest, specified as a sentinel/profile, is automatically monitored by the system using a combination of learning-based and event-driven techniques. The first prototype concentrated on the functionality of the WebVigiL system. This thesis extends the WebVigiL system in a number of ways. The primary focus of this thesis is the …


Efficient Main Memory Algorithms For Significant Interval And Frequent Episode Discovery, Sagar Hasmukh Savla Dec 2006

Efficient Main Memory Algorithms For Significant Interval And Frequent Episode Discovery, Sagar Hasmukh Savla

Computer Science and Engineering Theses

There is a considerable research on sequential mining of time-series data. Sensor-based applications such as MavHome require prediction of events for automating the environment using time-series data collected over a period of time. In these applications, it is important to predict tight and accurate intervals of interest to effectively automate the application. Also, detection of frequent patterns is needed for the automation of sequence of happenings. Although, there is a considerable body of work on sequential mining of transactional data, most of them deal with time point data and make several iterations over the entire data set for discovering frequently …


Probabilistic Localization Of Mobile Ad Hoc Networks, Rui Huang Dec 2006

Probabilistic Localization Of Mobile Ad Hoc Networks, Rui Huang

Computer Science and Engineering Dissertations

The mobile ad hoc network localization problem deals with estimating the physical location of the nodes that do not have a direct way (e.g., GPS) to determine their own locations. Being an enabling technology that is considered essential to the success of the future implementation of ad hoc networks in the real world, localization is a fundamental problem that needs to be solved with the best possible accuracy and efficiency. For this research, we study the localization problem in its various incarnations such as localization through static beacons, mobile beacons, dynamically deployed beacons and link longevity estimation based on relative …


Evading Existing Stepping Stone Detection Methods Using Buffering, Madhu Venkateshaiah Dec 2006

Evading Existing Stepping Stone Detection Methods Using Buffering, Madhu Venkateshaiah

Computer Science and Engineering Theses

To gain anonymity and complicate their apprehension, attackers launch attacks not from their own systems but from previously compromised systems called stepping stones. An effective way to detect stepping stones is by comparing of incoming and outgoing connections in a network to find correlations. For the sake of simplicity, earlier approaches ignore that an attacker can add chaff to a traffic stream. But in reality, the attacker may be able to modify applications to use cover traffic. We loosen some assumptions made by earlier researchers and propose a simple buffering technique that could be used by an attacker to evade …


A Distributed Sensor Data Management Infrastructure Based On 802.15.4/Zigbee Networks, Tianqiang Li Dec 2006

A Distributed Sensor Data Management Infrastructure Based On 802.15.4/Zigbee Networks, Tianqiang Li

Computer Science and Engineering Theses

Wireless sensor networks consist of a certain number of autonomous devices with sensor, every device has certain detection functionality like light, temperature pressure etc. Communication by using the radio frequency make these spatially distributed devices feasible to oversee the activities in a large scale of area/space. 802.15.4/ZigBee networks are slated to run in the unlicensed frequencies. It is a packet-based radio protocol aimed at very low-cost, battery-operated widgets and sensors that can intercommunicate and send low-bandwidth data to each other. This thesis covers the content of a software solution of data management for an 802.15.4 networks. Its main contribution lies …


Automated Software Testing Using Covering Arrays, Chinmay P. Jayaswal Dec 2006

Automated Software Testing Using Covering Arrays, Chinmay P. Jayaswal

Computer Science and Engineering Theses

Modern society is increasingly dependent on the quality of software systems. Software testing is a widely used approach to ensure software quality. Since exhaustive testing is impractical due to resource constraints, it is necessary to strike a balance between test efforts and quality assurance. Interaction testing is one approach to marrying these two qualities. It characterizes the system under test by a set of parameters and the respective test values (domain size) for each parameter. Instead of testing all possible combinations of values for all the parameters, interaction testing constructs a covering array as a test set to cover all …


Complementing Current Active Queue Management Schemes With Rechoke And Receiver-Window Modification (Rwm), Visvasuresh Govindaswamy Dec 2006

Complementing Current Active Queue Management Schemes With Rechoke And Receiver-Window Modification (Rwm), Visvasuresh Govindaswamy

Computer Science and Engineering Dissertations

Explicit Congestion Notification (ECN) and Active Queue Management (AQM) schemes have been proposed for present-day TCP/IP networks to better manage network congestion. ECN enabled AQMs were shown to have a promising advantage over existing drop-tail queues. However, when implemented, they were susceptible to the following problems: 1) the timeout mechanism or the duration of the reception of three duplicate acknowledgements (ACKs), due to early-dropped packets by these AQMs, delays the response time of TCP (in reducing the offered rate) 2) using ECN with these AQMs has its downsides: i) its messages may get delayed or dropped due to congestion in …


Trends Of Vehicular Emissions Due To The Effect Of Ethos® Fr As Fuel Additive, Shruthi Satyanarayan Dec 2006

Trends Of Vehicular Emissions Due To The Effect Of Ethos® Fr As Fuel Additive, Shruthi Satyanarayan

Civil Engineering Theses

The main objective of this research was to observe if the addition of the fuel additive Ethos Fuel Reformulator significantly reduced the emissions of CO, CO2, HC and NOX from a light duty vehicle. Data collection was carried out before and after the application of Ethos FR for both Peak and Off-peak traffic conditions, on highway as well as arterial test track. The OBS-1300 analyzed second by second concentrations of the tailpipe emissions. Data analysis was conducted and the following results were observed. 1. There was a significant reduction in NOx Emissions, with the maximum of 45% in the Arterial …


Optical Coherence Tomography Of Oral Mucosa, Nidhi Bharatbhai Mehta Dec 2006

Optical Coherence Tomography Of Oral Mucosa, Nidhi Bharatbhai Mehta

Bioengineering Theses

Oral cancer causes 120000* deaths annually around the world and 280000* new cases are diagnosed every year. Technology has developed and the death rate of oral cancer has improved over the last few decades; hence to improve the survival rate, development of a technique able to diagnose carcinomas in its early stages is very important. OCT is a non invasive imaging technique capable to provide high resolution microstructure images of tissue. A development of in vivo OCT; capable to image tissue with micrometer resolution and able to identify pre cancerous morphological changes non invasively could improve survival rate in cancer …


Using Part Of Speech Structure Of Text In The Prediction Of Its Readability, Jagadeesh Kondru Dec 2006

Using Part Of Speech Structure Of Text In The Prediction Of Its Readability, Jagadeesh Kondru

Computer Science and Engineering Theses

Readability formulas predict the reading difficulty associated with text. They typically output a U.S. school grade level that indicates the reading ability required of a person in order for him to comprehend that text. Ability to predict text readability is useful because it helps educators select appropriate texts for students and authors write texts accessible to the audience they target. Existing readability formulas are based on countable aspects of the text such as average sentence length and average word length. We propose a new readability formula, the Readability Index, which is based on the part-of-speech structure of sentences in a …


Experimental And Finite Element Based Investigations Of Shear Behavior In Reinforced Concrete Box Culverts, Anil Kumar Garg Dec 2006

Experimental And Finite Element Based Investigations Of Shear Behavior In Reinforced Concrete Box Culverts, Anil Kumar Garg

Civil Engineering Dissertations

This study evaluates the shear behavior and capacity of the precast concrete box culverts subjected to HS 20 truck wheel load. The most critical culvert behavior was considered by studying culverts subjected to zero depth fill and placed on rigid laboratory floor without bedding material. Three major phases were considered to complete the study, which included: (1) experimental program; (2) finite element modeling; and (3) development of distribution width and the determination of shear capacity. A full-scale experimental testing program was undertaken to perform tests on 24 typical precast concrete box culverts designated as per ASTM C 1433-05 with and …


Analysis Of Hat Sectioned Reinforced Composite Beams Including Thermal Effects, Kashif Ali Nayyer Syed Dec 2006

Analysis Of Hat Sectioned Reinforced Composite Beams Including Thermal Effects, Kashif Ali Nayyer Syed

Civil Engineering Dissertations

A simple analytical method for analyzing fiber reinforced polymeric composite beams with hat cross-section is presented. The method includes development of closed-form expression of the axial, bending and their coupling stiffness matrices for the composite beams. The stiffness matrices are obtained by transforming the actual geometrical cross-section of the beam into an equivalent plate using transformation matrices and Parallel Axis theorem. Ply stresses due to mechanical as well as thermal load can easily be obtained at any given location of the beam section. In this approach, the effect of induced in-plane deformation due to bending for an unsymmetrical cross-section is …


Spatial Patterns And Determinants Of Industrial Regional Growth In Mexico, 1993-2003: Implications For Regional Planning And Public Policy, Jesus Antonio Trevino Dec 2006

Spatial Patterns And Determinants Of Industrial Regional Growth In Mexico, 1993-2003: Implications For Regional Planning And Public Policy, Jesus Antonio Trevino

Public Affairs Dissertations

This research investigates industrial regional growth and its determinants in Mexico from 1993 to 2003. Strategies of local economic development, usually based on industrial promotion, require knowing main determinants of industrial regional growth. The case study shows that there is no variable with a systematically strong effect for all industries which policymakers and planners might directly control. This finding warns us about generic policy designs uncritically based on outcomes from other experiences. Although these results show a complex problem in terms of regional policy, some recommendations for industrial spatial distribution may, however, be derived from this study. For instance, during …


Risk, Resilience And Relocation: A Life Course Exploration Of Resettlement Experiences Of Public Housing Residents, Jan H. Johnston Dec 2006

Risk, Resilience And Relocation: A Life Course Exploration Of Resettlement Experiences Of Public Housing Residents, Jan H. Johnston

Public Affairs Dissertations

Spatial deconcentration of poverty has been the organizing framework of federally subsidized housing policy for well over a decade. During that time low-income families living in traditional public housing across the country have been involuntarily relocated. Household relocation into lower poverty middle class, while the underlying mobility goal, has proven difficult for many families. We continue to look for evidence for how and whether these families are able to adapt as they are scattered across urban settings. The research focus was to operationalize the resident's adaptive behavior pertaining to deconcentration of poverty by trait difference, familial/cultural cues and perceived institutional …


Optimization Of The Tool Path In A Robotic Environment, Mukund Venkatachari Narasimhan Dec 2006

Optimization Of The Tool Path In A Robotic Environment, Mukund Venkatachari Narasimhan

Mechanical and Aerospace Engineering Dissertations

The rising costs and demand coupled with shrinking energy generating resources has triggered the need for optimum use of energy resources, minimizing the overhead costs and maximizing the profits. Robots have been long touted as a fit replacement of human labor force in manufacturing sectors. Slowly there is increased presence of robots in automobile and electronic industries. Typically they are used for welding, painting, ironing, assembly, pick and place, inspection, and testing. Mass production, fulfilling the ever increasing demand, can be accomplished by robots because of their precision, speed of operation and high endurance capabilities. This dissertation comprises of two …


An Analytical Performance Management Framework Enabiling Enterprise Strategy Management, Amr Abu-Suleiman Dec 2006

An Analytical Performance Management Framework Enabiling Enterprise Strategy Management, Amr Abu-Suleiman

Industrial, Manufacturing, and Systems Engineering Dissertations

Performance management has gained noticeable interest from both researchers and executive in the past two decades. Financial measures are no longer a primary emphasis for researchers and executives. One of the most popular performance management methodologies is the Balanced Scorecard. The Balanced Scorecard framework facilitates translating strategy into objectives and initiatives across four perspectives. These perspectives are financial, customer, internal processes, and learning and growth. The second component of the balanced scorecard is strategy maps. Strategy maps outline the cause and effect between the four perspectives, and illustrate the value creation process through transforming leading indicators (operational measures) into lagging …