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Full-Text Articles in Engineering

Development Of Adsorption Filtration Process For Virus Removal For Drinking Water Treatment, Vishal Vijay Gawarikar May 2005

Development Of Adsorption Filtration Process For Virus Removal For Drinking Water Treatment, Vishal Vijay Gawarikar

Dissertations

Recent monitoring studies have indicated that many ground water (GW) sources would benefit from the development of effective technologies for removing viruses. Although reverse osmosis can achieve high log removal it is not economical. The main objective of this study is to test and validate a novel adsorption filtration (AF) technology for removing viruses from GW sources for drinking water production in New Jersey.

The convective diffusion of viruses to adsorbent particle surfaces in flow packed beds (FPB) enhances their removal efficiency if the adsorbent particle size can be decreased to about 100 microns. The development of effective virus removal …


Mechanics Of Biocell Landfill Settlements, Chamil Hiroshan Hettiarachchi May 2005

Mechanics Of Biocell Landfill Settlements, Chamil Hiroshan Hettiarachchi

Dissertations

Prediction of landfill gas generation and settlements are of concerns in design and maintenance of biocell landfills. Accurate settlement prediction is essential for design of piping systems used for the delivery of re-circulated leachate and recovery of landfill gas. Landfill settlement is the result of change in overburden stresses and biodegradation of waste. Biodegradation-induced settlement results from the re-arrangement of waste skeleton in response to the decomposition of waste mass.

Current practice of landfill settlement modeling is predominantly empirical, thus most of the available techniques make no attempt to simulate the real mechanisms of waste settlement. Traditionally compressibility index is …


Evaporating Cross Flow Spray Jets In Gas-Solid Circulating Fluidized Bed, Tong Hoon Lee May 2005

Evaporating Cross Flow Spray Jets In Gas-Solid Circulating Fluidized Bed, Tong Hoon Lee

Dissertations

Three-phase flow of solid-gas suspension with liquid spray is found in many industrial applications, including fluidized catalytic cracking in petroleum refinery process, and wet scrubbing process. This dissertation study is aimed to understand the gas-solid-liquid three-phase flow structure, phase interactions and transport in a gas-solid circulating fluidized bed where an evaporating cross-flow liquid spray jet from a rectangular nozzle with a fan angle is injected. The investigation is based on both numerical and experimental approaches. The numerical study is for detailed field descriptions of the flow structure, phase interaction and distributions whereas the experimental study is for simulation validations. The …


Fluid-Phase Thermodynamics From Molecular-Level Properties And Interactions Based In Quantum Theory, Steven G. Arturo May 2005

Fluid-Phase Thermodynamics From Molecular-Level Properties And Interactions Based In Quantum Theory, Steven G. Arturo

Dissertations

A methodology to predict the thermodynamics of macroscopic fluid systems from quantum chemistry and statistical thermodynamics has been developed. This work extends the group-contribution concepts most utilized in chemical engineering. Computational chemistry software is used to define the geometries and electron density profiles of target molecules. Atoms in Molecules theory and associated software packages are used to calculate rigorous properties of the functional groups within molecules of interest. These properties are incorporated into an intermolecular potential energy function which describes interactions between entire molecules as a set of interactions between functional groups. This information is applied to a lattice-fluid model …


Direct Numerical Simulations And Experimental Investigation Of Dielectrophoresis, Arun Thankamony John-Kadaksham May 2005

Direct Numerical Simulations And Experimental Investigation Of Dielectrophoresis, Arun Thankamony John-Kadaksham

Dissertations

This dissertation deals with the numerical and experimental studies of the phenomenon of dielectrophoresis, i.e., the motion of neutral particles in nonuniform electric fields. Dielectrophoresis is the translatory motion of neutral particles suspended in a dielectric medium when they are subjected to an external nonuniform electric field. The translatory motion occurs because a force called the dielectrophoretic force, which depends on the spatial variation of the electric field, acts on the particles. As the generation of force involves no moving parts and the particles can be moved without touching them, dielectrophoresis can be used in many applications, including manipulation and …


Analysis And Characterization Of The Integrated Dielectric Slab Waveguide-Wedge Antenna Using Iterative Mode-Matching Technique, Chairat Pinthong May 2005

Analysis And Characterization Of The Integrated Dielectric Slab Waveguide-Wedge Antenna Using Iterative Mode-Matching Technique, Chairat Pinthong

Dissertations

A rigorous solution for the TB and TM polarization to the dielectric wedge antenna fed by a slab waveguide of the same material is presented. The method of solution involves modeling the wedge as a sequence of step discontinuities and using an iterative procedure to track forward and backward partial wave fields, expressed as modal expansions, to obtain the rigorous field solution. Radiation patterns of directive gain are presented. All patterns smoothly decrease from a maximum in the endfire direction and exhibit very low side lobes. Longer length wedges are shown to produce higher directivity and smaller half-power beamwidths (HPBW). …


Virtual Transshipments And Revenue-Sharing Contracts In Supply Chain Management, Zhaoqiong Qin May 2005

Virtual Transshipments And Revenue-Sharing Contracts In Supply Chain Management, Zhaoqiong Qin

Dissertations

This dissertation presents the use of virtual transshipments and revenue-sharing contracts for inventory control in a small scale supply chain. The main objective is to maximize the total profit in a centralized supply chain or maximize the supply chain's profit while keeping the individual components' incentives in a decentralized supply chain.

First, a centralized supply chain with two capacitated manufacturing plants situated in two distinct geographical regions is considered. Normally, demand in each region is mostly satisfied by the local plant. However, if the local plant is understocked while the remote one is overstocked, some of the newly generated demand …


Simulation Of Creep In Nickel Based Single Crystal Superalloys, Yunhong Pang May 2005

Simulation Of Creep In Nickel Based Single Crystal Superalloys, Yunhong Pang

Dissertations

Nickel based single crystal Superalloys are finding wide spread use in high temperature gas turbines and other similar applications because of their superior high-temperature strength and creep properties as compared to the other materials. This is due to two factors: solid solution and precipitation strengthening of the gamma (γ) and gamma prime (γ') phases, and the elimination of grain boundaries. Creep of Nickel based single crystal Superalloys are caused by two primary mechanisms, dislocation creep and diffusion creep. Several factors that affect the creep life of Nickel based single crystal Superalloys are the specific microstructure, stress, temperature and rafting. Also, …


Security Information Management With Frame-Based Attack Presentation And First-Order Reasoning, Wei Yan May 2005

Security Information Management With Frame-Based Attack Presentation And First-Order Reasoning, Wei Yan

Dissertations

Internet has grown by several orders of magnitude in recent years, and this growth has escalated the importance of computer security. Intrusion Detection System (IDS) is used to protect computer networks. However, the overwhelming flow of log data generated by IDS hamper security administrators from uncovering new insights and hidden attack scenarios. Security Information Management (SIM) is a new growing area of interest for intrusion detection. The research work in this dissertation explores the semantics of attack behaviors and designs Frame-based Attack Representation and First-order logic Automatic Reasoning (FAR-FAR) using linguistics and First-order Logic (FOL) based approaches. Techniques based on …


Transceiver Design And System Optimization For Ultra-Wideband Communications, Hongshan Sheng May 2005

Transceiver Design And System Optimization For Ultra-Wideband Communications, Hongshan Sheng

Dissertations

This dissertation investigates the potential promises and proposes possible solutions to the challenges of designing transceivers and optimizing system parameters in ultra-wideband (UWB) systems. The goal is to provide guidelines for UWB transceiver implementations under constraints by regulation, existing interference, and channel estimation.

New UWB pulse shapes are invented that satisfy the Federal Communications Commission spectral mask. Parameters are designed to possibly implement the proposed pulses. A link budget is quantified based on an accurate frequency-dependent path loss calculation to account for variations across the ultra-wide bandwidth of the signal.

Achievable information rates are quantified as a function of transmission …


Quality-Of-Service Provisioning In High Speed Networks : Routing Perspectives, Gang Cheng May 2005

Quality-Of-Service Provisioning In High Speed Networks : Routing Perspectives, Gang Cheng

Dissertations

The continuous growth in both commercial and public network traffic with various quality-of-service (QoS) requirements is calling for better service than the current Internet's best effort mechanism. One of the challenging issues is to select feasible paths that satisfy the different requirements of various applications. This problem is known as QoS routing. In general, two issues are related to QoS routing: state distribution and routing strategy. Routing strategy is used to find a feasible path that meets the QoS requirements. State distribution addresses the issue of exchanging the state information throughout the network, and can be further divided into two …


Tcp Performance Enhancement In Wireless Networks Via Adaptive Congestion Control And Active Queue Management, Kai Xu May 2005

Tcp Performance Enhancement In Wireless Networks Via Adaptive Congestion Control And Active Queue Management, Kai Xu

Dissertations

The transmission control protocol (TCP) exhibits poor performance when used in error-prone wireless networks. Remedy to this problem has been an active research area. However, a widely accepted and adopted solution is yet to emerge. Difficulties of an acceptable solution lie in the areas of compatibility, scalability, computational complexity and the involvement of intermediate routers and switches.

This dissertation rexriews the current start-of-the-art solutions to TCP performance enhancement, and pursues an end-to-end solution framework to the problem. The most noticeable cause of the performance degradation of TCP in wireless networks is the higher packet loss rate as compared to that …


Gas Fluidization Of Nanoparticles, Qun Yu May 2005

Gas Fluidization Of Nanoparticles, Qun Yu

Dissertations

The primary objective of this study is to perform a systematic investigation on the gas fluidization of various nanoparticle agglomerates. Firstly, the gas fluidization characteristics and regime classifications without any additional external force fields are identified using both experimental measurements and modeling. Secondly, the effect of introducing certain external force fields on nanoparticle fluidization is experimentally investigated. Two external force fields were applied: sound waves from a loud speaker (acoustic assistance) and in-bed magnets that were excited by an external oscillating magnetic field (magnetic assistance). Thirdly, exploratory experimental research on the use of nanoparticle agglomerates as a granular filtration media …


On Rate Capacity And Signature Sequence Adaptation In Downlink Of Mc-Cdma System, Jianming Zhu May 2005

On Rate Capacity And Signature Sequence Adaptation In Downlink Of Mc-Cdma System, Jianming Zhu

Dissertations

This dissertation addresses two topics in the MC-CDMA system: rate capacity and adaptation of users' signature sequences. Both of them are studied for the downlink communication scenario with multi-code scheme.

The purpose of studying rate capacity is to understand the potential of applying MC-CDMA technique for high speed wireless data communications. It is shown that, to maintain high speed data transmission with multi-code scheme, each mobile should cooperatively decode its desired user's encoded data symbols which are spread with different signature sequences simultaneously. Higher data rate can be achieved by implementing dirty paper coding (DPC) to cooperatively encode all users' …


A Versatile Programming Model For Dynamic Task Scheduling On Cluster Computers, Dejiang Jin May 2005

A Versatile Programming Model For Dynamic Task Scheduling On Cluster Computers, Dejiang Jin

Dissertations

This dissertation studies the development of application programs for parallel and distributed computer systems, especially PC clusters. A methodology is proposed to increase the efficiency of code development, the productivity of programmers and enhance performance of executing the developed programs on PC clusters while facilitating improvement of scalability and code portability of these programs. A new programming model, named the Super-Programming Model (SPM), is created. Programs are developed assuming an instruction set architecture comprised of SuperInstructions (SIs). SPM models the target system as a large Virtual Machine (VM); VM contains functional units which are underlain with sub-computer systems and SIs …


Characterization Of Mismatch Between Behavioral Stimuli And Frmi Data Using The Kalman Filter, Jason Steffener May 2005

Characterization Of Mismatch Between Behavioral Stimuli And Frmi Data Using The Kalman Filter, Jason Steffener

Dissertations

The advance of blood oxygen level dependent function magnetic resonance imaging, (BOLD fMRI), allows researchers to non-invasively investigate the functioning human brain. The BOLD fMRI response to brief stimuli is called the hemodynamic response function (HRF), which can vary across brain regions and across subjects.

Models of the HRF are used to increase sensitivity of statistical maps; however, they often don't account for spatial and temporal variance. Physiological effects, such as learning, fatigue or habituation, introduce mismatch between statistical models and the data. Methods that use minimal a priori information and track time varying signals are able to show the …


Utility Of Remote Sensing Data In Retrieval Of Water Quality Consituents Concentrations In Coastal Water Of New Jersey, Ting Yu May 2005

Utility Of Remote Sensing Data In Retrieval Of Water Quality Consituents Concentrations In Coastal Water Of New Jersey, Ting Yu

Dissertations

Three important optical properties used for monitoring coastal water quality are the concentrations of chlorophyll (CHL), color dissolved organic matter (CDOM) and total suspended materials (TSM). Ocean color remote sensing, a technique to collect color data by detection of upward radiance from a distance (Bukata et al.,1995), provides a synoptic view for determining these concentrations from upwelling radiances. In the open ocean (Case-I), it is not difficult to derive empirical algorithms relating the received radiances to surface concentrations of water quality parameters. In coastal waters (Case-Il), there are serious unresolved problems in extracting chlorophyll concentration because of high concentration of …


Non-Linear Digital Control Of A Mckibben Muscle System, Surinkumar Patel May 2005

Non-Linear Digital Control Of A Mckibben Muscle System, Surinkumar Patel

Theses

McKibben muscles are pneumatic actuators that have potential application in the rehabilitation of persons with physical impairments. These actuators have been known to exhibit similarities in human musculoskeletal systems. In order to better understand and improve the closed - loop control of these pneumatic muscles, a physical joint model was constructed with an agonist and an antagonist muscle operating under non-linear control. With the use of LabVIEW software, compliant McKibben air muscles and Flock-of-Birds sensor, the author was able to implement and compare a standard bang-bang controller and experimental non-linear digital Proportional (P) controller. The feedback mechanism is based on …


Relationship Between The Autonomic Nervous System And The Recovering Heart Post Exercise Using Heart Rate Variability, Pierre Asselin May 2005

Relationship Between The Autonomic Nervous System And The Recovering Heart Post Exercise Using Heart Rate Variability, Pierre Asselin

Theses

The goal of this thesis is to determine if a relationship exists between the activity of the autonomic nervous system (ANS) and the speed of heart rate recovery post maximal exercise. The parasympathetic branch of the ANS was assessed during rest by obtaining the high frequency (HF) component of the heart rate variability (HRV) frequency spectrum. The recovery time was estimated by fitting an exponential curve to the heart rate post exercise where the exponent was used to calculate the time constant to indicate recovery time. A regression was then performed on the HF and recovery time in order to …


Difference-Expansion Based Reversible Data Hiding And Its Steganalysis, Guangsen Tian May 2005

Difference-Expansion Based Reversible Data Hiding And Its Steganalysis, Guangsen Tian

Theses

A novel reversible data embedding method was reported in a recent IEEE journal article. The method was based on difference expansion (DE) technique. It used redundancy in digital images to achieve a high embedding capacity, while keeping visual distortion of the stego-image low. In this thesis, this technique was studied and experimentally evaluated. An effective steganalysis scheme for this DE-based reversible data embedding method was proposed, which used 12-dimensional feature vectors and a Bayes Classifier. The proposed steganalysis scheme steadily achieved a correct classification rate of 99%.


Ambulatory Biopotential Measurement, Lakshmi Chitra Penugonda May 2005

Ambulatory Biopotential Measurement, Lakshmi Chitra Penugonda

Theses

Biopotential signals measure the electrical activity of different parts of the body. Conventional bedside monitors only provide information about the body under restricted conditions. Observation and documentation of biopotential signal during daily activities and the relation to patient symptoms may be important factors for clinical decision-making. Ambulatory monitoring helps to monitor the biopotential signal of a patient in the natural environment. The effective ambulatory system can help a physician to diagnose the patient's abnormality.

In this project, a low cost and flexible ambulatory biopotential system, compared to the commercially available systems, was designed and tested. Concurrently a software program was …


Evaluation Of Knox Group Contribution Parameters Using Quantum Based Molecular And Group Properties, Myriam Carrillo May 2005

Evaluation Of Knox Group Contribution Parameters Using Quantum Based Molecular And Group Properties, Myriam Carrillo

Theses

Thermodynamic property prediction through the group contribution methods has been improving. However, the approaches considered in the past present not only limitations on the physical basis but often have restrictions as to certain substances, such as isomers. A new group contribution method is proposed that uses AIM theory, which is based on computational chemistry and quantum mechanics, to overcome these limitations by treating each molecule individually. An evaluation of this method as applied to the Knox model is proposed and analyzed for Vapor Liquid Equilibrium (VLE) of mixtures with the help of nine global parameters that are obtained by correlation. …


Enabling Cost Aware Routing With Auctions In Wireless Ad-Hoc Networks, Ali Yuksel May 2005

Enabling Cost Aware Routing With Auctions In Wireless Ad-Hoc Networks, Ali Yuksel

Theses

Battery power is a precious resource in wireless ad-hoc networks, and most routing protocols that have been proposed so far do not generate cost efficient routes. In this thesis, a novel auction-based cost-aware routing scheme, called CARA, is presented. CARA is designed as an extension of the MAC layer, and is shown to improve the cost efficiency of existing ad-hoc routing protocols through dynamic power control, while introducing only minimal additional overhead. The MAC layer at each node is given the capability to run local sealed-bid second-price auctions for the user data packets that need to be transmitted, and to …


Cluster-Based Wireless Mobile Ad-Hoc Network Security, Mandur Bajra Bajracharya May 2005

Cluster-Based Wireless Mobile Ad-Hoc Network Security, Mandur Bajra Bajracharya

Theses

A wireless ad-hoc network is a cooperative communication network deployed with a specific purpose. It is characterized by dynamically changing topology with no fixed infrastructure which exhibits a perfectly vulnerable state for a number of different kinds of attacks.

This thesis proposes a novel technique of achieving security in wireless mobile ad hoc networks by integrating a simple clustering and a voting mechanism together. The purpose of forming a cluster is to facilitate security in the network and the voting is performed to support the decision making process in the cluster. A procedure of forming small homogenous clusters throughout the …


Stereo Vision Algorithm Using Propagation Of Correspondences Along An Array Of Cameras, Danyan Ganjali May 2005

Stereo Vision Algorithm Using Propagation Of Correspondences Along An Array Of Cameras, Danyan Ganjali

Theses

One well known problem in stereo vision is the trade-off between precision and accuracy.

In a conventional two camera model, as the baseline separating the two cameras becomes smaller, the images that both cameras produce become more identical. This results in a more accurate set of correspondences, however at the same time causing less precise depth measurement due to the small angle used for triangulation. Similarly, in a larger baseline model, the depth measurement is more precise while the correspondences are not as accurate as of the shorter baseline model. This thesis proposes a method that promises to solve the …


Evaluation Of Unifac Group Interaction Parameters Usijng Properties Based On Quantum Mechanical Calculations, Hansan Kim May 2005

Evaluation Of Unifac Group Interaction Parameters Usijng Properties Based On Quantum Mechanical Calculations, Hansan Kim

Theses

Current group-contribution methods such as ASOG and UNIFAC are widely used for approximate estimation of mixture behavior but unable to distinguish between isomers. Atoms in Molecules (AIM) theory can solve these problems by using quantum mechanics and computational chemistry to compute atomic contributions to molecular properties and to intermolecular interactions. Rigorously defined properties available through AIM theory and new functional group definitions are used for the UNIFAC model to predict the behavior of various mixtures. Results are presented for various mixtures with nine regressed global parameters to optimize model's predictive capability. The results are also compared to analogous results for …


Analysis Of Acceleration And Deceleration During Cyclic Exercise, Jeena Vadi May 2005

Analysis Of Acceleration And Deceleration During Cyclic Exercise, Jeena Vadi

Theses

The Cyclic Exercise Protocol is a novel protocol that is designed to create a series of cyclic waves of exercise and recovery. This exercise protocol involves short bursts of exercise lasting for 60 seconds or less followed by a period of complete cardio recovery. This study involves the analysis of the acceleration and the deceleration regions of the cyclic exercise sessions. The objective of this study was to develop an algorithm to quantitatively analyze the acceleration and the deceleration regions of cyclic exercise sessions. The acceleration and the deceleration regions of cycles were split into three segments and each segment …


Analysis Of Mhpdm Algorithm For Data Hiding In Jpeg Images, Pooja Gore May 2005

Analysis Of Mhpdm Algorithm For Data Hiding In Jpeg Images, Pooja Gore

Theses

In the recent years, there has been a great deal of interest in developing a secure algorithm for hiding information in images, or steganography. There has also been a lot of research in steganalysis of images, which deals with the detection of hidden information in supposedly natural images. The first section of this thesis reviews the steganography algorithms and steganalysis techniques developed in the last few years. It discusses the breadth of steganographic algorithms and steganalytic techniques, starting with the earliest, based on LSB flipping of the DCT coefficients, to more recent and sophisticated algorithms for data hiding and equally …


On Performance Analysis Of Optimal Diversity Combining With Imperfect Channel Estimation, Yong Peng May 2005

On Performance Analysis Of Optimal Diversity Combining With Imperfect Channel Estimation, Yong Peng

Theses

The optimal diversity combining technique is investigated for multipath Rayleigh and Ricean fading channel with additive white Gaussian noise where only imperfect channel knowledge is available at the receiver. The non-observable estimation error contributes as an additive source of noise which is not white. Therefore, the optimal combining weight is derived taking into consideration the imperfect channel knowledge.

The bit error rate for BPSK modulation over correlated Rayleigh and Ricean fading channel is derived for minimum mean square channel estimation using pilot symbol assisted modulation. Analytical result and Monte-Carlo simulation are presented for specific channel and estimation models to demonstrate …


Planar Visual Fusion Scintigraphy, Jacob Puthiamadathil May 2005

Planar Visual Fusion Scintigraphy, Jacob Puthiamadathil

Theses

Planar scintigraphy, while providing useful information about the distribution of the radiopharmaceutical being used, often does not provide adequate information about the surrounding anatomical structures. A proposed method to solve this problem is by registering and fusing a scintigraphic image with a digital visual image. Fusing planar scintigraphic images with visual photographic images to supply an anatomic correlate to regions of radiopharmaceutical accumulation has been explored in this study. The digital visual image will provide a context for the relevant structures in the scintigraphic image. The validity of using one set of affine transformation parameters for registering all patient data …