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Effects Of Cyclic Strain And Growth Factors On Vascular Smooth Muscle Cell Responses, Kytai Truong Nguyen, Hao Xu Jan 2009

Effects Of Cyclic Strain And Growth Factors On Vascular Smooth Muscle Cell Responses, Kytai Truong Nguyen, Hao Xu

Bioengineering Faculty Publications - Archive

Under physiological and pathological conditions, vascular smooth muscle cells (SMC) are exposed to different biochemical factors and biomechanical forces. Previous studies pertaining to SMC responses have not investigated the effects of both factors on SMCs. Thus, in our research we investigated the combined effects of growth factors like bFGF (basic fibroblast growth factor), TGF-�� (transforming growth factor ��) and PDGF (platelet-derived growth factor) along with physiological cyclic strain on SMC responses. Physiological cyclic strain (10% strain) significantly reduced SMC proliferation compared to static controls while addition of growth factors bFGF, TGF-�� or PDGF-AB had a positive influence on SMC growth …

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Attributes Selection And Package Design To Maximize Visibility Of Objects, Md Zahiduzzaman Miah Jan 2009

Attributes Selection And Package Design To Maximize Visibility Of Objects, Md Zahiduzzaman Miah

Computer Science and Engineering Dissertations - Archive

In recent years, there has been significant interest in the development of ranking functions and efficient top-k retrieval algorithms to help users in ad-hoc search and retrieval in databases (e.g., buyers searching for products in a catalog). We introduce a complementary problem: how to guide a seller in selecting the best attributes of a new tuple (e.g., a new product) to highlight so that it stands out in the crowd of existing competitive products and is widely visible to the pool of potential buyers. For example, assume one wants to sell an iPod in e-commerce site, but the title allows …

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Topology Optimization Using Hyper Radial Basis Function Network, Aditya P. Apte Jan 2009

Topology Optimization Using Hyper Radial Basis Function Network, Aditya P. Apte

Mechanical and Aerospace Engineering Dissertations - Archive

Topology optimization has been conventionally used in automobile and aerospace industries to produce lightweight structures for minimum compliance or maximum fundamental frequency. Today, topology optimization finds application in solving diverse types of problems ranging from medicine to consumer products. Popular continuum based method SIMP fails to provide global solution due to too many variables involved. In this work, a novel hyper radial basis function network is presented as topology description function. The proposed approach provides drastic reduction in number of design variables involved in topology optimization. This makes the use of heuristic global solution possible. Parallel processing, reanalysis formulation and …

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Optimal-Control Theoretic Methods For Optimization And Regulation Of Distributed Parameter Systems, Jennifer Dawn Goss Jan 2009

Optimal-Control Theoretic Methods For Optimization And Regulation Of Distributed Parameter Systems, Jennifer Dawn Goss

Mechanical and Aerospace Engineering Dissertations - Archive

Optimal control and optimization of distributed parameter systems are discussed in the context of a common control framework. The adjoint method of optimization and the traditional linear quadratic regulator implementation of optimal control both employ adjoint or costate variables in the determination of control variable progression. As well both theories benefit from a reduced order model approximation in their execution. This research aims to draw clear parallels between optimization and optimal control utilizing these similarities. Several applications are presented showing the use of adjoint/costate variables and reduced order models in optimization and optimal control problems. The adjoint method for shape …

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Transient Flow Analysis Of Filling In Pulse Detonation Engine, Veera Venkata Suneel Jinnala Jan 2009

Transient Flow Analysis Of Filling In Pulse Detonation Engine, Veera Venkata Suneel Jinnala

Mechanical and Aerospace Engineering Theses - Archive

The Pulse Detonation Engine (PDE) is considered to be a propulsion system of future air vehicles. The objective of the present study is to model an efficient inlet system for filling the detonation tube completely with the fuel/air mixture. In the present study the filling processes is modeled numerically using CFD code FLUENTTM. Calculations for the gas flow are carried out by solving the Navier-Stokes equations coupled with the k- ? turbulence model. Five different inlet configurations were proposed and simulated in both two-dimensionally and three-dimensionally. The model with an orifice plate at the inlets ensured the desired optimum results. …

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Guidance Of Receiver Aircraft To Rendezvous With Tanker In The Presence Of Wind, Jane-Wit Kampoon Jan 2009

Guidance Of Receiver Aircraft To Rendezvous With Tanker In The Presence Of Wind, Jane-Wit Kampoon

Mechanical and Aerospace Engineering Theses - Archive

This thesis work addresses the problem of aircraft rendezvous in the presence of prevailing wind for automated aerial refueling operations. A modified point-parallel rendezvous procedure is defined. The tanker aircraft performs a racetrack maneuver along a pre-specified refueling orbit. The receiver aircraft enters the refueling area through a fixed point and flies along the refueling line that is aligned with on of the straight legs of the race track. It is the responsibility to meet the tanker at the rendezvous point. A virtual target is used to define the trajectory of the refueling orbit. A nonlinear guidance algorithm is used …

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Experimental Investigation Of Flow Boiling And Spray Cooling On Enhanced Surfaces In Fc-72, Gilberto Morenp Jan 2009

Experimental Investigation Of Flow Boiling And Spray Cooling On Enhanced Surfaces In Fc-72, Gilberto Morenp

Mechanical and Aerospace Engineering Dissertations - Archive

In this study the effect of a recently developed, thermally conductive microporous coating on flow boiling and spray cooling performance was studied using FC-72 as the working fluid. The overall goal is to further increase heat transfer in forced convection systems and in doing so, provide a viable option for future cooling applications. In flow boiling, the coating increased heat transfer coefficients by as much as 400% and produced values exceeding 40,000 W-m-2 K-1. This enhancement is believed to be a result of both an increase in active nucleation sites and a decrease of the superheated liquid layer. It is …

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A Comprehensive Study Of Recycled Concrete Aggregates As A Drainable Base Layer For Pavements, Juan Bosquez Jan 2009

A Comprehensive Study Of Recycled Concrete Aggregates As A Drainable Base Layer For Pavements, Juan Bosquez

Civil Engineering Dissertations - Archive

The use of recycled materials in construction is becoming increasingly popular due to the shortage of raw materials. Coupled with the environmental concerns surrounding the quarrying of natural minerals, waste materials are being considered as viable replacement sources. By recycling waste materials, available landfill space is increased and costs of transportation are reduced. This dissertation study was conducted to evaluate the use of recycled concrete aggregates as flexible base as per the requirements of the Texas Department of Transportation (2004). Two sources of recycled aggregates and one source of natural limestone aggregate were collected from the Dallas/Fort Worth Area and …

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Reliability Of Advanced Dielectrics In Gate Oxide And Device Level Packaging In Mems, Mohammad Shahriar Rahman Jan 2009

Reliability Of Advanced Dielectrics In Gate Oxide And Device Level Packaging In Mems, Mohammad Shahriar Rahman

Electrical Engineering Dissertations - Archive

The focus of this work is to study the feasibility, reliability and applicability of advanced dielectrics in both Metal Oxide Semiconductor Field Effect Transistor (MOSFET) gate oxide and device level packaging for Microelectromechanical Systems (MEMS). The scaling of silicon based MOSFET is approaching physical limits imposed by atomic structure. This continuous scaling trend of complementary MOSFET technologies introduces new challenges relating to power, heat and device behavior. To overcome the power dissipation and heating problems arising from gate leakage, high dielectric constant (high-k) materials are proposed. Hafnium based high-k dielectric layers and metal gate electrodes have been extensively investigated as …

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Optimization Of Hydrogen Filling Station, Weiping Xiao Jan 2009

Optimization Of Hydrogen Filling Station, Weiping Xiao

Electrical Engineering Theses - Archive

Due to the price hike of the fossil fuel and the concern of the global warming, the hydrogen economy can be envisioned to address those problems. After the Energy Bill was announced in 2005, a transition of national energy system from hydrocarbon to hydrogen had been recognized. However, safe and convenient refueling and widespread availability of hydrogen from various energy sources are the prerequisite for the development of hydrogen economy. This research focuses on the hydrogen filling station with on-site hydrogen production by electrolysis of water. The virtual wind farm and on-site installed photovoltaic (PV) supply the main and renewable …

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Battery Identification Methods Based On Equivalent Circuit Model, Matthew Cole Ragsdale Jan 2009

Battery Identification Methods Based On Equivalent Circuit Model, Matthew Cole Ragsdale

Electrical Engineering Theses - Archive

Development of an intelligent battery diagnostic system is a necessity for future transportation industry. These technologies will have the potential to create profound impact in other industries such as portable electronics. This thesis reports on battery identification methods that are primarily engineered to detect the chemistry, number of cells, and state of charge in an unknown package of batteries. The proposed methods have the potential to be used for condition monitoring in a known set of batteries thereby, creating a health monitoring apparatus that can be an integral part of a battery management system using any of the prominent lead …

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Blocking Reader: Design And Implementation Of A Low-Cost Passive Uhf Rfid Blocking Reader, Gaurov Narayanaswamy Jan 2009

Blocking Reader: Design And Implementation Of A Low-Cost Passive Uhf Rfid Blocking Reader, Gaurov Narayanaswamy

Electrical Engineering Theses - Archive

In this thesis I present a low-cost passive UHF ISO 18000-6C RadioFrequency Identification, or RFID, reader that is feasible for mobileand privacy applications. Low cost readers are necessary to achievethe promised cost savings and enhanced revenue generation that theInternet of Things promises to deliver. Low cost readers may beinstalled virtually everywhere, providing real-time asset monitoringand a host of new and innovative applications yet to be conceived.While pervasively deployed readers provide tremendous benefits, thepromiscuous nature of the 18000-6C tags means that the readers alsopose a threat to personal security and privacy. Privately owned tags on a person will be read by …

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Dlp Hyperspectral Imaging For Surgical And Clinical Utility, Robert Paul Francis Jan 2009

Dlp Hyperspectral Imaging For Surgical And Clinical Utility, Robert Paul Francis

Bioengineering Theses - Archive

Surgeons want technology to help them see differences in tissue chemistry. If they know how oxygenated tissues and organs are during medical procedures, they are more able to eliminate dangerous tissues and maintain viable organs. Hyperspectral imaging non-invasively measures the optical absorbance spectrum of each pixel in a spatial field of view and, with chemometric image processing, can visualize the spatial distribution of tissue oxygenation. Current hyperspectral imaging systems are too slow to monitor real-time physiological changes in live tissue. Therefore, a novel DLP Hyperspectral Imaging (DLP HSI) system is developed for real-time, non-invasive, in-vivo imaging of tissue chemistry in …

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A Novel Device For The Establishment Of An Animal Model Mimicking Spinal Deformity Surgery For Neurological Deficit Risk Mitigation, Bradley Elmer Jan 2009

A Novel Device For The Establishment Of An Animal Model Mimicking Spinal Deformity Surgery For Neurological Deficit Risk Mitigation, Bradley Elmer

Bioengineering Theses - Archive

Correction forces during spine deformity surgery impart significant multidirectional stress forces to the spinal cord, which in some cases result in severe damage to the spinal cord and permanent paralysis, the most feared complication. Animal models are critical for the development of neuroprotective strategies. However, those currently available are limited to contusion, transection, or unidirectional distraction injuries, which fail to replicate the multidirectional forces that occur during spine corrective surgery. In order to develop an improved model of distraction spinal cord injury we designed a device based on intervertebral grip fixation and linear actuators, capable of inducing controllable bidirectional distraction …

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In Situ Crosslinkable Polyesters For Tissue Engineering And Drug Delivery, Dipendra Raj Gyawali Jan 2009

In Situ Crosslinkable Polyesters For Tissue Engineering And Drug Delivery, Dipendra Raj Gyawali

Bioengineering Theses - Archive

In situ crosslinkable elastic materials are increasingly being explored for various biomedical applications such as drug delivery and tissue engineering due to their site specific nature. The creation of an in situ crosslinkable elastomer rich in pendant chemistry has been a challenge in the field of biomaterials. Herein, we have developed two new in situ biodegradable materials: poly(octamethylene maleate citrates) (POMC) and poly(poly(ethylene glycol) maleate citrate) (PPEGMC). These materials are all low molecular weight in their pre-polymeric form, which shows their potential to be used as an injectable biomaterial. The preservation of pendant carboxylic and hydroxyl groups in these polymeric …

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Development Of An Optical Spectroscopic Method To Detect Neurohemodynamic Changes Induced By Pain In Rats, Sweta Narvenkar Jan 2009

Development Of An Optical Spectroscopic Method To Detect Neurohemodynamic Changes Induced By Pain In Rats, Sweta Narvenkar

Bioengineering Theses - Archive

In my optical spectroscopy study, multi-channel, thin optical probes with short source-detector separation have been implemented, calibrated, and used along with a multi-channel spectrometer as a quantitative technique to observe changes in vascular hemoglobin concentration and hemoglobin oxygen saturation as well as light scattering of tissues. Each of the four needle probes used in my study consists of two bifurcated fibers; one fiber is connected to a halogen light source and the other fiber to a CCD-array spectrometer having a spectral window from 450 nm to 900 nm. Each fiber is 100 micron in diameter. As we utilized the four …

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Integration Of Data Mining Algorithms And Control Charts For Multivariate And Autocorrelated Processes, Weerawat Jitpitaklert Jan 2009

Integration Of Data Mining Algorithms And Control Charts For Multivariate And Autocorrelated Processes, Weerawat Jitpitaklert

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

The objective of this dissertation is to integrate state-of-the-art data mining algorithms with statistical process control (SPC) tools to achieve efficient monitoring in multivariate and autocorrelated process. Process monitoring and diagnosis have been widely recognized as important and critical tools in system monitoring for detection of abnormal behavior and quality improvement. Although traditional SPC tools are effective in simple manufacturing processes that generate a small volume of independent data, these tools are not capable of handling the large streams of multivariate and autocorrelated data found in modern manufacturing/service systems. As the limitations of SPC methodology become increasingly obvious in the …

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Nonlinear Dynamic Analysis Of Hybrid Frames, Dobrinka Radulova Jan 2009

Nonlinear Dynamic Analysis Of Hybrid Frames, Dobrinka Radulova

Civil Engineering Theses - Archive

This study proposes a hybrid frame system consisting of rigid and semi-rigid connections subjected to a dynamic loading. Two building geometries are chosen to represent low-rise and high-rise buildings. Multiple locations for placement of semi-rigid connections are proposed, and the hybrid systems with the most efficient energy dissipation are identified. During this analysis, five earthquake records are used to provide a spectrum of frequencies. Five practical semi-rigid connection types and one connection with analytical parameters are also modeled into the selected hybrid combinations by applying zero-length springs at the ends of beams, in which their nonlinear constitutive relation is defined …

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Energy Efficient Routing Structures And Wakeup Schemes For Wireless Sensor Networks, Byoung Lee Jan 2009

Energy Efficient Routing Structures And Wakeup Schemes For Wireless Sensor Networks, Byoung Lee

Computer Science and Engineering Dissertations - Archive

Wireless sensor networks, which consist of a large number of sensor nodes and a base station, are used for many applications aimed at collecting information. Each sensor node is equipped with a small amount of battery, limited memory, finite radio range and small CPU. It gathers required information and it sends the information to the base station. The large number of sensors can cover a large area by cooperating with each other to build a multi-hop wireless network. However, the small amount of battery is one of the critical concerns because sensor network life time depends on battery longevity. It …

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Novel Nonparametric Control Charts For Monitoring Multivariate Processes, Panitarn Chongfuangprinya Jan 2009

Novel Nonparametric Control Charts For Monitoring Multivariate Processes, Panitarn Chongfuangprinya

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

The objective of this dissertation is to develop novel nonparametric control charts to effectively monitor and diagnose multivariate processes with a minimal set of modeling assumptions. Statistical process control (SPC) is a set of procedures that uses statistical techniques to measure, analyze, and reduce process variation. A control chart, which is a special type of graph showing the results of periodic inspections over time, is the primary and most successful SPC tool in real-world applications. This dissertation proposes two nonparametric multivariate control charts based on (1) a support vector machines (SVM) algorithm and (2) a linkage ranking algorithm. The first …

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Unsupervised Data Mining Methods For Functional Data Analysis And Feature Selection, Panaya Rattakorn Jan 2009

Unsupervised Data Mining Methods For Functional Data Analysis And Feature Selection, Panaya Rattakorn

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

The objective of this dissertation is to develop new unsupervised data mining methods for functional data analysis and feature selection. Unsupervised learning is a modeling process that facilitates the extraction of implicit patterns and elicits the natural groupings within the dataset without using any information from the output (response) variable. This dissertation consists of two main parts: (1) unsupervised clustering approaches for functional data analysis and (2) unsupervised feature selection. Functional data analysis has gained significant attention from a variety of disciplines. In this dissertation we propose an effective clustering procedure to categorize a number of profiles that are formed …

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Methodology To Forecast Product Returns For The Consumer Electronics Industry, Amit Potdar Jan 2009

Methodology To Forecast Product Returns For The Consumer Electronics Industry, Amit Potdar

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Reverse logistics has gained much attention in recent years. It is becoming a value added area of a supply chain network day by day. For enterprises, it has therefore become essential to manage the reverse flow of materials in an efficient way to gain competitive advantage. One important aspect of reverse logistics is to have a correct and timely estimation of the reverse flow of materials. Improved forecast accuracy leads to a better decision making in strategic, tactical and operational areas of an organization. Intrinsic (time series) and extrinsic (causal) forecasting are some of the well known and frequently used …

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Academic Achievement Among Psychology Undergraduates Enrolled In Webct-Assisted Research Design And Statistics Courses, Susan Annette Autrey Jan 2009

Academic Achievement Among Psychology Undergraduates Enrolled In Webct-Assisted Research Design And Statistics Courses, Susan Annette Autrey

Psychology Dissertations - Archive

The current study evaluated performance of 2443/2444 students and the use of WebCT. Undergraduate psychology majors at UT Arlington who successfully completed PSYC 2443 and 2444, Research Design and Statistics I and II, during the Fall/Spring semesters of 2006-2007, 2007-2008, and 2008-2009 semesters were part of this study (N=132). Students became more efficient users of WebCT over the course of the two semesters. Communication variables were significant predictors of performance (Lecture, Lab, and Total grade) in 2443 but not for 2444 performance. WebCT usage was predictive of of Lab grades in 2443 and all performance variables in 2444. The current …

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Theia: Radio Frequency Identification Performance Analysis Tool, Jason Francis Pereira Jan 2009

Theia: Radio Frequency Identification Performance Analysis Tool, Jason Francis Pereira

Electrical Engineering Theses - Archive

In recent years there has been an increase in the adoption of Radio FrequencyIdentication or RFID systems for most applications that deal with investment (products/people) tracking. The ideal requirements of investment tracking systems are :-lost-cost, zero maintenance and eciency.Although the applications are similar in nature, the scenarios and operating environmentsare not. This is a problem that plagues an inexpert consumer of RFIDsystems. RFID systems are application specic and hence have to be properly customizedto the application environment. One solution to this problem is to have theinstallation set up by an expert, but this is impractical due to recurring costs for …

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Implementation Of Autonomous Navigation And Obstacle Avoidance On An Unmanned Ground Vehicle, Pranav Naresh Desai Jan 2009

Implementation Of Autonomous Navigation And Obstacle Avoidance On An Unmanned Ground Vehicle, Pranav Naresh Desai

Electrical Engineering Theses - Archive

This thesis presents the implementation of a novel distributed embedded systems approach to real-time obstacle avoidance and guidance for an Unmanned Ground Vehicle (UGV). The mobility, real-time, and limited size requirements of UGVs, result in computationally limited and resource constrained hardware platform. The use of distributed computational resources, such as multiple embedded micro-controllers, enables the distribution of the computing resources for obstacle avoidance and guidance system functionalities. The resulting system's complexity is significantly greater than that of a single high performance processor performing all of the above functions. The hardware platform is integrated with sensors and micro-controllers to function as …

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"Independence, Liberty, And Justice": The Birth, Life, And Death Of Haden Edwards' Fredonian Rebellion, John Wesley Strunc Jan 2009

"Independence, Liberty, And Justice": The Birth, Life, And Death Of Haden Edwards' Fredonian Rebellion, John Wesley Strunc

History Theses - Archive

To populate Texas, the government of Mexico encouraged foreign empresarios like Stephen F. Austin to bring families and settle. One of those men, Haden Edwards, hoped to turn a profit with his grant in the area around Nacogdoches. Local authorities opposed his efforts, he became involved in political and social squabbles, and the Mexican government felt compelled to revoke his grant. Seeing no alternative, Edwards engineered the Fredonian Rebellion, hoping to maintain his lands.Characters including Edwards, Martin Parmer, and Samuel Norris turned a local dispute involving politics, money, and control, into what could have become a large scale revolution. Only …

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Design And Study Of Phase Locked Loop For Space Applications In Sub-Micron Cmos Technology, Partha Pratim Ghosh Jan 2009

Design And Study Of Phase Locked Loop For Space Applications In Sub-Micron Cmos Technology, Partha Pratim Ghosh

Electrical Engineering Dissertations - Archive

This work proposes a successful design of a radiation hard phase locked loop (PLL) using Silicon-on-Sapphire CMOS (SOS) technology for space applications. A fully self-bias radiation hard PLL providing frequency of 2.5 GHz has been designed for the first time on SOS technology. SOS technology is used to provide radiation hardness from Single Event Effects (SEE), an improvement over the use of commercially available bulk CMOS process. Innovative designs of VCO implemented in the PLL, architectural modifications in the use of buffers, bias stages, asynchronous dividers and optimization of fully self-bias design provide hardness from Total Ionization Dose (TID). Self-bias …

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Designing Multi-Objective Reverse Logistics Networks Using Genetic Algorithms, Sanya Yimsiri Jan 2009

Designing Multi-Objective Reverse Logistics Networks Using Genetic Algorithms, Sanya Yimsiri

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Reverse logistics (RL) involves management of activities that include collection, sort/storage, transportation, recovery, disposal and re-distribution. The product return process is more complicated than forward logistics due to presence of multiple reverse distribution channels, individualized returns with small quantities, extended order cycles associated with product exchanges and a variety of recovery and disposition options. Reverse logistics has been gaining interest from many sectors due to rising costs, environmental concern and tougher regulations. As a result, good reverse logistics network design can help business save costs and meet their bottom lines in this competitive global environment. Most of the previous research …

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Enabling Context-Aware Applications In Smart Environments‏, Roman Arora Jan 2009

Enabling Context-Aware Applications In Smart Environments‏, Roman Arora

Computer Science and Engineering Theses - Archive

Recognizing human activities is an important feature for the development of contextaware applications that are so fundamental to enabling assistive environments. Only once these applications are able to determine the activities that their inhabitants are performing can they assist the individuals and their special needs. In order to do this, it is necessary to build models that can accurately capture and recognize the observed patterns. Equally important is the need to manage and distribute the information that has been inferred, and to provide Quality of Service (QoS) guarantees so that context-aware applications can react effectively to emergent situations. In this …

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Query Auditing Against Partial Disclosure, Mayur Motgi Jan 2009

Query Auditing Against Partial Disclosure, Mayur Motgi

Computer Science and Engineering Theses - Archive

Many government agencies, businesses, and nonprofit organizations need to collect, analyze, and report data about individuals in order to support their short-term and long-term planning activities. Statistical Databases therefore contain confidential information such as income, credit ratings, type of disease, or test scores of individuals. Such data are typically stored online and analyzed using sophisticated database management systems (DBMS) and software packages. On one hand, such database systems are expected to satisfy user requests of aggregate statistics related to non-confidential and confidential attributes. On the other hand, the system should be secure enough to guard against a user's ability to …

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