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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 - Archive

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 …

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The Development Of A Design Ontology For Products And Processes, Md Baniamin Sarder Dec 2006

The Development Of A Design Ontology For Products And Processes, Md Baniamin Sarder

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

This research develops a methodology called, Design Knowledge Acquisition Process (DKAP) for creating ontology of product and process design using IDEF5 and to develop a consistency matrix for checking accuracy of captured information. It constructs an ontology of a generic product and process design using the developed DKAP methodology. Designing products and processes is very challenging and vital for manufacturing enterprises to stay in the competitive market. Manufacturers want to launch their products in the market as quickly as possible while satisfying their customers in terms of quality, cost and delivery. In order to lunch the products early and/or to …

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Convex Versions Of Multivariate Adaptive Regression Splines And Implementations For Complex Optimization Problems, Dachuan Thomas Shih Dec 2006

Convex Versions Of Multivariate Adaptive Regression Splines And Implementations For Complex Optimization Problems, Dachuan Thomas Shih

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Multivariate Adaptive Regression Splines (MARS) provide a flexible statistical modeling method that employs forward and backward search algorithms to identify the combination of basis functions that best fits the data. In optimization, MARS has been used successfully to estimate the value function in stochastic dynamic programming, and MARS could be potentially useful in many real world optimization problems where objective (or other) functions need to be estimated from data, such as in simulation optimization. Many optimization methods depend on convexity, but a nonconvex MARS approximation is inherently possible because interaction terms are products of univariate terms. In this dissertation, convex …

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A Methodology For Evaluating The Performance Of Reverse Supply Chains In Consumer Electronics Industry, Srikanth Sastry Yellepeddi Dec 2006

A Methodology For Evaluating The Performance Of Reverse Supply Chains In Consumer Electronics Industry, Srikanth Sastry Yellepeddi

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Enterprises around the world are employing reverse supply chain practices to generate profit making opportunities while meeting new regulations. As a result of the rapid progress in technology the product lifecycles are shrinking faster than ever. In the face of global competition, heightened environmental regulations and a wealth of additional profits and improved corporate image opportunities, performing the reverse supply chain operations at a world class level is becoming quintessential. These factors in addition to the inherent complexity of reverse supply chains due to the uncertainties associated with the quantity, quality, and timing of returns make returns management very complicated. …

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Full Issue, The Mcnair Team Dec 2006

Full Issue, The Mcnair Team

McNair Scholars Research Journal

No abstract provided.

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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 - Archive

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 …

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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 - Archive

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 …

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Neural Network Solution For Fixed-Final Time Optimal Control Of Nonlinear Systems, Tao Cheng Dec 2006

Neural Network Solution For Fixed-Final Time Optimal Control Of Nonlinear Systems, Tao Cheng

Electrical Engineering Dissertations - Archive

In this research, practical methods for the design of H2 and H-Infinity optimal state feedback controllers for unconstrained and constrained input systems are proposed. The dynamic programming principle is used along with special quasi-norms to derive the structure of both the saturated and optimal controllers in feedback strategy form. The resulting Hamilton-Jacobi-Bellman (HJB) and Hamilton-Jacobi-Isaacs (HJI) equations are derived respectively. Neural networks are used along with the least-squares method to solve the Hamilton-Jacobi differential equations in the H2 case, and the cost and disturbance in the H-Infinity case. The result is a neural network unconstrained or constrained feedback controller that …

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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 - Archive

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 …

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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 - Archive

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 …

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Performance Analysis And Design Of Space-Time Codes, Chen Liao Dec 2006

Performance Analysis And Design Of Space-Time Codes, Chen Liao

Electrical Engineering Dissertations - Archive

In this dissertation, performance and design of space-time codes have been studied. The main objective of this dissertation has been to improve the performance of space-time codes. This dissertation covers a wide range of topics in space-time codes. It involves theoretical analysis, design, and implementation for space-time trellis codes, space-time turbo codes, and orthogonal space-time codes. We begin with the study of performance analysis of upper bound of pair-wise error probability (PEP) and exact PEP. The exact PEP is derived using a straightforward method. The exact PEP provides a better understanding of the performance behavior to the other range of …

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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 - Archive

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 …

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Scalar Equilibria For N-Person Games, Narakorn Engsuwan Dec 2006

Scalar Equilibria For N-Person Games, Narakorn Engsuwan

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

In this dissertation we develop a scalarization approach for one-shot, n-person games by defining the notion of Scalar Equilibria. We first show that existing solution concepts can be represented as Scalar Equlibria. For example, Regret, Disappointment, and Joint Equilibrium can be determined by defining Regret, Disappointment, and Joint Scalar Equilibria. These scalar equilibria are useful for finding pure strategies when pure Regret, Disappointment, and Joint Equilibria do not exist. Next, we present the Maximin Scalarization Equilibrium to yield maximin solution concept. In addition, we propose other Scalar Equilibria for various notions of rationality. The Aspiration Scalar Equilibrium is developed for …

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Dynamic Stability Analysis Of Large-Scale Power Systems Using A Fast Investigation Method, Ming-Tse Kuo Dec 2006

Dynamic Stability Analysis Of Large-Scale Power Systems Using A Fast Investigation Method, Ming-Tse Kuo

Electrical Engineering Dissertations - Archive

Following power market deregulation and the proposed standard market design, the activities of cross boundary power transactions are increased significantly. Traditional company based stability analysis can not satisfy today's operating environment. However, simulating the entire interconnection power system may exceed the capacity of existing commercial stability analysis software. Fortunately, most of the stability problems are started from the local level. One will be able to avoid most of the system wide stability issues by mitigating the problems in the early stage. Based on eigenvector decompositions of the Jacobian, this dissertation proposes a new algorithm for performing the dynamic stability problem …

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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 - Archive

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 …

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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 - Archive

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 …

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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 - Archive

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 …

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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 - Archive

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 …

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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 - Archive

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 …

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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 - Archive

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 …

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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 - Archive

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 …

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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 - Archive

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 …

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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 - Archive

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 …

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Fabrication, Characterization And Hall Mobility Analysis Of Mos Devices With Low-K And High-K Dielectric Materials, Rakshit Agrawal Dec 2006

Fabrication, Characterization And Hall Mobility Analysis Of Mos Devices With Low-K And High-K Dielectric Materials, Rakshit Agrawal

Electrical Engineering Theses - Archive

Scaling of MOSFETS has led to leakage current problems in SiO2 dielectric based MOSFETS. This has led to the introduction of high-k dielectric materials which can afford greater physical thickness and achieve the same capacitance with lesser equivalent oxide thickness. But the high-k devices have certain limitations like channel mobility degradation. Mobility degradation in high-k MISFETS is discussed in this work using Hall measurements. The MOS devices were fabricated with SiO2 and HfSiO, on p-type silicon substrate. The fabrication process flow used for both type of MOS devices is explained. Characterization and analysis was performed for the determination of various …

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Kairos, Nomos, New Media: Paradox As A Reservoir For Invention, Robert Leston Dec 2006

Kairos, Nomos, New Media: Paradox As A Reservoir For Invention, Robert Leston

English Dissertations - Archive

In the wake of the so-called "social turn" in writing studies, the scholarship of invention has enjoyed renewed interest. This dissertation is primarily concerned with invigorating the research of invention by turning towards viable but untapped generative approaches for composing that have been forged by artists working in areas external to composition studies by putting into practice what media theorist Gregory Ulmer calls a "heuretic" approach to invention. (I use the term heuretic to indicate the appropriation of an inventional model from a domain or discipline such as art, though other domains such as engineering would suit just as well.) …

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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 - Archive

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 …

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Ut Arlington Library Notes, V.12, No.2, Fall 2006, University Of Texas At Arlington Library Dec 2006

Ut Arlington Library Notes, V.12, No.2, Fall 2006, University Of Texas At Arlington Library

UT Arlington Library Notes

Former publication of the UT Library intended to foster community support and appreciation for Library Programs and services and to spotlight grants and contributions. It was published during the 1990s and 2000s.

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An Analysis Of Waves With Applications To Music, Kristen Creech Dec 2006

An Analysis Of Waves With Applications To Music, Kristen Creech

McNair Scholars Research Journal

No abstract provided.

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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 - Archive

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 …

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Design And Optimization Of Heat Spreaders And Selection Of Fan In Laptop, Kranthi Kumar Manne Sambaiah Dec 2006

Design And Optimization Of Heat Spreaders And Selection Of Fan In Laptop, Kranthi Kumar Manne Sambaiah

Mechanical and Aerospace Engineering Theses - Archive

Technical advancements lead to the need for faster processors and reduced sizes in electronic systems. The urge for faster and compact systems leads to two major problems. Firstly over heating of chips which degrade the chip performance and secondly formation of heat spots on the surface which makes the user uncomfortable. Thermal management engineers, as a result have a major challenge in improving the cooling systems. In this research project simulation using the thermal modeling tool selected is Icepak. The prototype model of the laptop is designed, boundary conditions are applied and analysis is done. The results so obtained in …

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