Digital Commons Network^™

Chat And Instant Messaging : The Risks Of Secondary Orality, Gregory P. Kohn

Theses

The synchronous nature of chat and instant messaging (IM) make them unique among computer-enabled communications technologies in that their real-time exchange of data allows for rich media experiences, even though users can only use text symbols to trade messages. Chat and IM are also important in that they enable secondary orality, or the merger of the most beneficial aspects of orally-based cultures with the well-documented benefits of print and text. Where print in the modem day has fostered contemplative behavior and inward thought among human beings, chat and IM breathe vitality into print and, in a sense, allow print to …

Towards Digital Library Service Integration, Prateek Shrivastava

Theses

Digital Library Service Integration (DLSI) aims to provide a systematic approach in integrating the services and collections of National Science and Digital Library. The National Science and Digital Library collections can share the services among themselves in a totally integrated environinent. Collections as such will require no change to plug into the DLSI architecture. Collections will keep using the services of NSDL in the similar manner as before. These services will in turn pass few parameters to the services of DLSI. With the help of these parameters, wrappers will fetch the details and priority of the users. These wrappers will …

Addition Of A Chain-Cell Search Method And A Van Der Waals Force Model To A Particle Dynamics Code, Michael J. Sweetman

Theses

This project studies the implementation of a computational time saving technique and adds an additional force model into a discrete element method simulation code. Both aspects of the project are focused on increasing the versatility of an existing particle dynamics code by increasing the execution speed and available force models for simulation.

The first portion of the project consisted of adding a function to the collision detection mechanism to hash the particles into a spatial grid. This hashing function allows a search for near neighbor particles to be restricted to the space immediately adjacent to the particle of interest, thereby …

The Illusion Of Science : Images Of Science On Stage, Preethi Ganapathy

Theses

Science has long been regarded as a process of thinking, of pursuing the truth. This quest traditionally has been reserved for an elite group of thinkers, since at least the time of Aristotle, who was considered as the undisputed authority on philosophical truth, including that which we call science. The Scientific Revolution challenged Aristotle's authority and paved the way for the new method of evaluating scientific truths developed by Bacon, Descartes, and Galileo. Science became, over time, a process of inquiry open to all social and economic classes and accessible to all. In the twentieth century, the role of science …

Fresh Kills Dumped : A Policy Assessment For The Management Of New York City's Residential Solid Waste In The Twenty-First Century, Aaron William Comrov

Theses

New York City ceased disposing of its daily residential solid waste output within its municipal borders in March 2001 when the Department of Sanitation completed its phase-down of the Fresh Kills landfill on Staten Island. The closure of this facility has, for the first time in history, stripped New York City of its waste management selfsufficiency, created a situation in which municipal officials are reliant on private firms and other governmental jurisdictions for disposal services, and contributed to deteriorating fiscal, environmental, political, economic, social and practical conditions.

Consequent and concurrent to this predicament, a multitude of alternative policies have been …

Feedback Algorithm For Switch Location : Analysis Of Complexity And Application To Network Design, Yuriy S. Polyakov

Theses

An accelerated feedback algorithm to solve the single-facility minisum problem is studied with application to designing networks with the star topology. The algorithm, in which the acceleration with respect to the Weiszfeld procedure is achieved by multiplying the current Weiszfeld iterate by an accelerating feedback factor, is shown to converge faster than the accelerating procedures available in the literature. Singularities encountered in the algorithm are discussed in detail. A simple practical exception handling subroutine is developed. Several applications of the algorithm to designing computer networks with the star topology are demonstrated. Applications of the algorithm as a subroutine for multi-switch …

Uber-Claws : Unsupervised Pattern Classification For Multi-Unit Extracellular Neuronal Burst Extraction, Rama Natarajan

Theses

To further an understanding of how a neuronal population generates patterns of rhythmic activity, the temporal dynamics of the group of neurons must be formalized. Essential to this pursuit, is the ability to reliably detect and separate the classes of single-unit neuronal activity from multi-unit extracellular signals recorded in a single channel. This study proposes a unified approach to automatically detect and classify single-unit bursts, and to observe the precise onset and offset of burst activity. Existing approaches to the problem fundamentally depend on the statistics of spike waveform variability, both extrinsic and intrinsic to the neuron. In contrast, the …

Analysis Of Random Packing Of Uniform Spheres Using The Monte Carlo Simulation Method, Sai S. Tulluri

Theses

The study of random packing of spheres has had a long history. It particularly interests many researchers because randomly packed hard spheres exhibit some features of the properties of simple liquid, e.g. the packing density and the radial distribution. Many researchers have studied random packing both experimentally and also by using computer simulation.

Monte Carlo simulation method was used to generate random loose packing of hard spheres. Packing characteristics like packing density, radial distribution function, co-ordination, angular distribution and fabric tensor have been computed for this packing system.

The packing density for a system of 8000 particles with a diameter …

Spatio-Temporal Correlation Models For Indoor Mimo Channels, Kaustubha Raghukumar

Theses

Accurate modeling of the spatio-temporal cross-correlation between the subchannels of a multiple-input multiple-output (MIMO) channel is an important prerequisite of multi-element antenna system design. In this thesis, a new model for indoor MIMO channels is proposed, and a closed form expression for the spatio-temporal cross-correlation function is derived. This new analytical correlation expression includes many physical parameters of interest such as the angle-of-arrivals at the base station and the user, the associated angle spreads, and other parameters, in a compact form. Comparison of this model with narrowband indoor MIMO data collected at Brigham Young University exhibits the utility of the …

The Rationale For Preserving Neighborhood Open Space In Newark, New Jersey's North Ward, Stephen M. Wiessner

Theses

A study was conducted to determine the shifts in open space availability between 1950 and 2003 in four neighborhoods in the North Ward of Newark, New Jersey. Total open space in square feet and open spaces ten thousand square feet and less were quantified to determine the extent of usable open space for the creation of community gardens or vest pocket parks.

The study identified large reductions of open space recently in the two least affluent study areas. The two more affluent study areas have also lost open space recently, but not at the magnitude of the poorer study areas. …

Shape Finding Of Fabric Structures Using Grid Method, Armin Bischof

Theses

Fabric structures can span large distances with a very low self-weight, which makes them very efficient for covering huge areas. They have attractive shapes and an appealing architecture. These properties make them very popular and they are used in many different kinds of buildings. Airports, stadiums and halls are typical examples where the use fabric structures is often recommendable.

Fabric structures are built mainly out of fabric and cables; two structural members that can only take tension stresses. Therefore these structural members must be prestressed in such a way that their shape can carry all loads that might affect the …

Data Recording And Analysis Of American Sign Language, Robert Michael Demarco

Theses

American Sign Language (ASL) is a form of communication that is used by the Deaf. It consists of hand shapes and gestures to express words and phrases. Translators on the market today consist of interpreting a simple form of ASL known as finger spelling. In order to develop a more effective translator, instrumentation was developed utilizing a Flock of Birds and Cyberglove system to record in hand shapes and movements in a LabVIEW environment. Experimentation done included reading in data and subjectively analyzing the data recorded for accuracy. Initial results have show that the instrumentation worked and data was recorded …

Sparse Matrix Product Implementation On Field Programmable Gate Arrays (Epgas), Amit Mahendra Sheth

Theses

If dense matrix multiplication algorithms are used with sparse matrices, they can result in a large number of redundant calculations, as numerous elements in sparse matrices are zero valued, thus available resources and time may be wasted. The algorithm discussed here aims to take advantage of the sparseness of the matrices by multiplying only nonzero elements.

The NIOS development board from Altera is used for implementing the above algorithm. First a sequential program in the C programming language is downloaded onto the FPGA and run by the NIOS soft-processor. Then the same board is also used for a parallel implementation …

An Application In Bioinformatics : A Comparison Of Affymetrix And Compugen Human Genome Microarrays, Milind Misra

Theses

The human genome microarrays from Compugen® and Affymetrix® were compared in the context of the emerging field of computational biology. The two premier database servers for genomic sequence data, the National Center for Biotechnology Information and the European Bioinformatics Institute, were described in detail. The various databases and data mining tools available through these data servers were also discussed. Microarrays were examined from a historical perspective and their main current applications-expression analysis, mutation analysis, and comparative genomic hybridization-were discussed. The two main types of microarrays, cDNA spotted microarrays and high-density spotted microarrays were analyzed by exploring the human genome microarray …

Discrete Element Simulation And Nonlinear Dynamic Analysis Of Particles In A Simple Lattice Structure, Liam E. Buckley

Theses

The study of particles interacting in lattice structures allows for insight into the complex interactions of granular flow, and the adaptation of such structures to mechanical apparatuses to handle the separation of bulk particulate matter. Applying methods of computer analysis to the interactions taking place within the particle-lattice system provides a particle level methodology to the study of the phenomenon taking place, as well as a stepping stone for future design of related devices.

A two prong approach is presented to the study of such particle-lattice systems. The first approach is composed of adapting an existing discrete element computer code …

Experimental And Modeling Studies Of Formation Of Products Of Incomplete Combustion And Chlorocarbon Incineration, Roman Brukh

Dissertations

The two-stage combustor facility was used to investigate the process of chlorocarbon incineration and formation of products of incomplete combustion. For this purpose methylene chloride was used as a chlorine-containing compound. The propose of this research was to obtain a better understanding of the incineration process of chlorocarbons, such as methylene chloride, especially regarding its destruction efficiency and formation of products of incomplete combustion. For measuring near-real time very low concentrations of benzene and methylene chloride, on-line microtrap gas chromatography system was used.

The experimental system was validated using a known combustion reaction mechanism from literature. Modeling of combustion process …

Handgrip Pattern Recognition, Zong Chen

Dissertations

There are numerous tragic gun deaths each year. Making handguns safer by personalizing them could prevent most such tragedies. Personalized handguns, also called "smart" guns, are handguns that can only be fired by the authorized user. Handgrip pattern recognition holds great promise in the development of the smart gun.

Two algorithms, static analysis algorithm and dynamic analysis algorithm, were developed to find the patterns of a person about how to grasp a handgun. The static analysis algorithm measured 160 subjects' fingertip placements on the replica gun handle. The cluster analysis and discriminant analysis were applied to these fingertip placements, and …

Joint Buffer Management And Scheduling For Input Queued Switches, Dequan Liu

Dissertations

Input queued (IQ) switches are highly scalable and they have been the focus of many studies from academia and industry. Many scheduling algorithms have been proposed for IQ switches. However, they do not consider the buffer space requirement inside an IQ switch that may render the scheduling algorithms inefficient in practical applications.

In this dissertation, the Queue Length Proportional (QLP) algorithm is proposed for IQ switches. QLP considers both the buffer management and the scheduling mechanism to obtain the optimal allocation region for both bandwidth and buffer space according to real traffic load. In addition, this dissertation introduces the Queue …

Acoustical Characterization And Parameter Optimization Of Polymeric Noise Control Materials, Emile N. Homsi

Dissertations

The sound transmission loss (STL) characteristics of polymer-based materials are considered. Analytical models that predict, characterize and optimize the STL of polymeric materials, with respect to physical parameters that affect performance, are developed for single layer panel configuration and adapted for layered panel construction with homogenous core. An optimum set of material parameters is selected and translated into practical applications for validation.

Sound attenuating thermoplastic materials designed to be used as barrier systems in the automotive and consumer industries have certain acoustical characteristics that vary in function of the stiffness and density of the selected material. The validity and applicability …

Closed-Loop Control Of Vortex Shedding By Means Of Lorentz Force, Xiaoyun Sun

Dissertations

When an incompressible fluid flows past a circular cylinder, vortex shedding occurs as soon as the Reynolds number exceeds about 40. Vortex shedding is usually undesirable, as it generates a significant increase in drag, as well an oscillating lift force on the cylinder leading to cross-stream structural vibrations. Flow control to either delay the appearance of vortex shedding or fully suppress it has attracted much attention during the last decade. The focus of this dissertation is to control vortex shedding from a circular cylinder by applying an external electromagnetic field. As in previous works, the latter is generated by electrodes …

Evaporating Crossflow Sprays In Gas-Solid Flows, Guangliang Liu

Dissertations

Injection of evaporating sprays into gas-solid flows is encountered in many engineering processes such as energy production industry and chemical industry. The phenomenon involves phase change, three-phase interactions, heat and mass transfer. All of these characteristics control the process efficiency, pollutant production and product quality. However, very limited studies are available on the evaporating spray jets in gas-solid flows, especially on the spray evaporation rate within a gas-solid medium. A combined study of experiments and theoretical analysis has been carried out here to investigate the fundamental mechanism of evaporating Crossflow spray jets in gas-solid flows.

In this study, in addition …

Study Of Vapor/Gas Permeation Using Thin Immobilized Liquid Membrane, Gordana Obuskovic

Dissertations

To improve liquid membrane selectivity and stability for removal of vapor and gases from a gas stream, a thin immobilized liquid membrane (ILM) has been studied. Low vapor pressure liquid solvent/solutions were immobilized in part of the micropores of a hydrophilic, hydrophobic or ceramic hollow fiber substrate. To prepare such thin ILMs, three approaches were used: evaporation of the a volatile solvent; acrylic acid-grafted hollow fibers providing a thin hydrophilic layer; pressurization technique.

For removal of volatile organic compound (VOC), a thin ILM of silicone oil incorporated in the micropores of a hydrophobic hollow fiber with a silicone rubber coating …

Thermochemistry And Kinetics In Pyrolysis And Oxidation Of Oxygenated Chlorocarbons And Chlorinated Aromatics, Li Zhu

Dissertations

Thermochemical. properties, Δf_H°₂₉₈, S°₂₉₈, and Cp°(T) (5<=T/K<=6000), are determined using different ab inifio and density functional theory methods for three chloromethyl radicals, CH₂Cl, CHCl₂, CCl₃, all chlorobenzenes from monochlorobenzene to hexachlorobenzene, and all chlorophenols from ortho-, meta-, para-chlorophenol to pentachlorophenol. The B3LYP/6-31G(d,p) method is used in the structure optimization. The B3LYP/6-31G(3df,2p), QCISD(T)/6-3 I G(d,p), and CB S-Q methods are used in single point calculations of total electronic energies. Harmonic vibration frequencies are scaled for zero point energies and thermal corrections. Isodesmic reaction(s) are utilized at each calculation level to determine Δf_H°₂₉₈ of each species. Contributions to S°₂₉₈ and Cp°(T) from …

Robust And Efficient Video/Image Transmission, Xi Min Zhang

Dissertations

The Internet has become a primary medium for information transmission. The unreliability of channel conditions, limited channel bandwidth and explosive growth of information transmission requests, however, hinder its further development. Hence, research on robust and efficient delivery of video/image content is demanding nowadays.

Three aspects of this task, error burst correction, efficient rate allocation and random error protection are investigated in this dissertation. A novel technique, called successive packing, is proposed for combating multi-dimensional (M-D) bursts of errors. A new concept of basis interleaving array is introduced. By combining different basis arrays, effective M-D interleaving can be realized. It has …

Analysis Of Gene Expression Data Using Expressionist 3.1 And Genespring 4.2, Indu Shrivastava

Theses

The purpose of this study was to determine the differences in the gene expression analysis methods of two data mining tools, Expressionistic^TM 3.1 and GeneSpring^TM 4.2 with focus on basic statistical analysis and clustering algorithms. The data for this analysis was derived from the hybridization of Rattus norvegicus RNA to the Affymetrix RG34A GeneChip. This analysis was derived from experiments designed to identify changes in gene expression patterns that were induced in vivo by an experimental treatment.

The tools were found to be comparable with respect to the list of statistically significant genes that were up-regulated by more …

Electrohydrodynamical Manipulation Of Particles Based On Dielectrophoresis, Oleksii Vasylyschuk

Theses

The movement of matter in a non-uniform electric field, termed dielectrophoresis, is of interest to scientists of various branches: physics, chemistry, engineering, and life science. To chemists and physicists it is a science of many varied phenomena. To engineers it is a source of new and useful techniques for separating materials or improving materials’ behavior. To ecologists it provides a major means of minimizing pollution. To life scientists it offers new ways to study and manipulate cells and their subparticles, and to help unravel the nature of living systems.

The purpose of this thesis is to concentrate on some aspects …

Reconsidering Restoration, Brian Hoffner

Theses

What does the process of ecological restoration actually produce? For some restoring nature is a point of no contention. By replacing ecosystems that have been damaged by human interference, humans are taking proper responsibility for their actions. However, the environmental ethics community is all but in agreement over humans' obligations to damaged ecosystems. Some in the field claim that it is human's responsibility to perform "wild gardening", through restorations, to "our" environments. While other philosophers insist that these acts produce "faked nature".

This thesis offers a compromise vision of the meaning of restoration. The author uses the concept of Autonomous …

Implementation Of A Two-Dimensional Discrete Element Method To Describe Granular Materials Composed Of Elliptical Cohesionless Particles, Juan Jose Martinez Alvez

Theses

This work is aimed at developing a discrete element simulation that models the contact between elliptical grains or particles in granular materials. The goal is to implement an algorithm to carry out collision detection between ellipses as well as ellipsoidal objects. The practical issue here is that the real shape of macroscopic grains can be approximated better using elliptical curves than using spherical curves. In addition, the simulation model will also be valid for spheres, since these objects are special cases of ellipsoids.

An accurate contact detection algorithm was investigated by means of two different formulations. The first formulation determines …

Characterization And Corrosion Of Bcc-Tantalum Coating Deposited On Aluminum And Steel Substrate By Dc Magnetron Sputtering, Chirag Joshi

Theses

Tantalum is one of the most versatile highly refractory corrosion-resistant metals. Tantalum coating can be used as an effective corrosion barrier if it is continuous, free from defects and it adheres well to the substrate. A DC magnetron sputtering technique was used to deposit tantalum on aluminum and steel. X-ray diffraction measurements revealed that the tantalum films produced by sputtering had two crystallographic structures: a body centered cubic α-phase and a metastable tetragonal β-phase. Tough and ductile alpha phase tantalum is preferred over the hard and brittle beta phase tantalum, as a protective coating. Alpha phase coatings were successfully deposited …

Computer Simulation Of Automotive Disc Brake Noise, Vadims Milovs

Theses

Disc brake noise continues to be a major concern throughout the automotive industry despite efforts to reduce its occurrence. Many articles are written on this subject, but there still is no agreement on what exactly causes disc brake noise and what part of the braking system is responsible for it.

The goal of current research was to build a simplified but inclusive mathematical model of a disc brake system and investigate it using Matlab software. The twodimensional model including damping, Stribeck effect and stick-slip friction was built.

The model is unique in a way that all the similar models have …