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Cognitive And Non-Cognitive Characteristics As Predictors Of College Success Among African-American And Caucasian Students In A Comprehensive Community College, Denise Marie Scameheorn Jan 2001

Cognitive And Non-Cognitive Characteristics As Predictors Of College Success Among African-American And Caucasian Students In A Comprehensive Community College, Denise Marie Scameheorn

Dissertations

Problem. This study examined the relationship of selected cognitive and non-cognitive characteristics of community college students, particularly Aftican-American and Caucasian students, with self-concept, class attendance patterns, and GPA.

Method. The subjects were 185 community college students. They completed the Non- Cognitive Questionnaire and the Learning and Study Strategies Inventory. Demographic data were obtained from the college student database. Instructors provided attendance and grade records.

Results.

1. Student self-concept was related to age, academic background and skills, and selected learning and study strategies.

2. Student class attendance was related to family support, ethnicity, academic background and skills, and motivation.

3. Student …


The Impact Of Intentional Learning Experiences For Personal Spiritual Formation On Seminary Students, Carol M. Tasker Jan 2001

The Impact Of Intentional Learning Experiences For Personal Spiritual Formation On Seminary Students, Carol M. Tasker

Dissertations

Problem. Many seminary students describe their time in seminary as a spiritual desert. Most Protestant seminaries do not provide spiritual formation classes for their students, thinking that such measures are unnecessary or inappropriate for theological education, or assuming that the church is the place for spiritual formation to take place. Nevertheless, pastors are expected to be spiritual leaders, and the pastor’s spirituality is ranked by laity as the highest priority needed by seminary graduates for effective church ministry. A literature survey of theological education shows that, in the last 150 years, students have consistently recognized their need for help …


The Effects Of Colonization On The Career Development And Occupational Choices Of African Students Studying In The United States, Augustine E. Bessong Dec 2000

The Effects Of Colonization On The Career Development And Occupational Choices Of African Students Studying In The United States, Augustine E. Bessong

Dissertations

A quantitative research design was utilized to understand the perceptions of the effects of colonization on career choices and occupational development of Africans in the United States. In face-to-face, 60-90 minute interviews using a semistructured interview guide developed by the researcher, participants were asked open-ended questions about the effects of colonization on their career choices and occupational development. Using purposeful sampling, 12 African male and female students, 7 enrolled at one Southeastern university and S from a large metropolitan city in the Southeastern United States, were interviewed for data collection.

Interviews were tape-recorded and transcribed. Transcripts were analyzed using the …


Information Retrieval And Mining In High Dimensional Databases, Xiong Wang Oct 2000

Information Retrieval And Mining In High Dimensional Databases, Xiong Wang

Dissertations

This dissertation is composed of two parts. In the first part, we present a framework for finding information (more precisely, active patterns) in three dimensional (3D) graphs. Each node in a graph is an undecoraposable or atomic unit and has a label. Edges are links between the atomic units. Patterns are rigid substructures that may occur in a graph after allowing for an arbitrary number of whole-structure rotations and translations as well as a small number (specified by the user) of edit operations in the patterns or in the graph. (When a pattern appears in a graph only after the …


Turbulent Mixing And Chemical Reaction In Baffled Stirred Tank Reactors : A Comparison Between Experiments And A Novel Micromixing-Based Computational Fluid Dynamics Model, Otute Akiti Aug 2000

Turbulent Mixing And Chemical Reaction In Baffled Stirred Tank Reactors : A Comparison Between Experiments And A Novel Micromixing-Based Computational Fluid Dynamics Model, Otute Akiti

Dissertations

The optimization of reaction processes to maximize the yield of a desired product while minimizing the formation of undesired by-products is one of the most important steps in process development for drug manufacturing or fine chemical production. In many situations the kinetics of product formation can be quite complex and involve a number of intermediate steps as well as parallel and serial reactions. This renders the systems sensitive to the operating conditions. Often, upon scale-up, a decrease in the yield of the desired product is experienced, while more undesired by-products are produced. A large number of interrelated variables influence the …


Feasibility Study To Extract Iron And Chromium From Chromium Contaminated Soils, Wiwat Kamolpornwijit Aug 2000

Feasibility Study To Extract Iron And Chromium From Chromium Contaminated Soils, Wiwat Kamolpornwijit

Dissertations

Chromium contaminated soils, besides being recognized for toxic and hazardous hexavalent chromium, contain high iron concentrations. At some sites, concentrations of iron oxide are higher than 30%. Both iron and chromium in soils have recyclable value provided they can be either concentrated in the oxide form or separated as metal. The concentrated oxide can be used as a substitute for the iron ore. The extracted metal can also be recycled in the steel industry. The objective of this study is to study the feasibility of extracting iron and chromium from soils.

Chromium contaminated soils, can be classified into two groups, …


Knowledge Discovery In Biological Databases : A Neural Network Approach, Qicheng Ma Aug 2000

Knowledge Discovery In Biological Databases : A Neural Network Approach, Qicheng Ma

Dissertations

Knowledge discovery, in databases, also known as data mining, is aimed to find significant information from a set of data. The knowledge to be mined from the dataset may refer to patterns, association rules, classification and clustering rules, and so forth. In this dissertation, we present a neural network approach to finding knowledge in biological databases. Specifically, we propose new methods to process biological sequences in two case studies: the classification of protein sequences and the prediction of E. Coli promoters in DNA sequences. Our proposed methods, based oil neural network architectures combine techniques ranging from Bayesian inference, coding theory, …


Deactivation And Enhancement Effects Of Sulfur On Supported Platinum Oxidation Catalysts, Mark Ladolcetta Aug 2000

Deactivation And Enhancement Effects Of Sulfur On Supported Platinum Oxidation Catalysts, Mark Ladolcetta

Dissertations

The effects of sulfur poisoning on the oxidation activity of 1.5 % Pt/γ-Al2O3, Pt/TiO2, Pt/ZrO2, and Pt/SiO2, were investigated in this study. Each catalyst was poisoned with an H2S/air or SO2/air mixture at 400°C for 24 hours and a sulfur concentration of 200 ppm. The complete oxidation of mixtures of I % CO, methane, ethane, ethene, ethyne, propane, propene, and n-butane in air were measured over fresh and sulfurpoisoned catalysts.

Non-methane alkane oxidation activity was enhanced significantly after sulfur poisoning on all four catalysts. The temperatures …


Axisymetric Vibrations Of Homogeneous And Sandwich Spherical Shells With A Hole At The Center, Wai-Kwong Wong Aug 2000

Axisymetric Vibrations Of Homogeneous And Sandwich Spherical Shells With A Hole At The Center, Wai-Kwong Wong

Dissertations

Based on Hamilton's principle and the theory of elasticity, both linear and nonlinear governing equations of motion are derived for elastic spherical shells. Most of the analysis is focused on the free axisymmetric vibrations of homogeneous and sandwich shallow spherical shells. The nonlinear behavior, which allows for small deflections, is also discussed.

The linear vibrations of homogeneous and sandwich shallow spherical shells with a hole at the center are investigated with emphasis placed on the effect of thickness-shear deformation and rotatory inertia. The effects of curvature and the size of the central hole are studied for free axisymmetric motions of …


A Preliminary Investigation Of The Acceptability And Effectiveness Of Computer-Based Adjunctive Parent Training For Child Noncompliance, Dwayne M. Munneke Aug 2000

A Preliminary Investigation Of The Acceptability And Effectiveness Of Computer-Based Adjunctive Parent Training For Child Noncompliance, Dwayne M. Munneke

Dissertations

Noncompliance with parent requests is a commonly reported behavior problem for clinic-based child referrals. Parent skills training has been empirically demonstrated as an effective treatment for helping parents increase positive child behaviors and decrease negative behaviors. Unfortunately, many therapists and agencies are unable to implement parent-training programs due to limited therapist training, limited economic resources, or long waiting lists.

Adjunctive, computer-based, treatment programs have become increasingly popular in both research and clinical settings for facilitating psychological assessment and intervention. This project involved the development and preliminary investigation of the effectiveness and acceptability of a computer-based program designed to supplement therapist-delivered …


Public Policy: Affirmative Action, Social Equity, And Employment Patterns In Michigan's Construction Industry 1966-1997, Henry Joseph Bowers Jun 2000

Public Policy: Affirmative Action, Social Equity, And Employment Patterns In Michigan's Construction Industry 1966-1997, Henry Joseph Bowers

Dissertations

Affirmative action public policy did not experience much debate when it was put in place during the late 1960’s. However, the debate is occurring in the 1990s. Its merits are being weighed and there are movements locally to eliminate affirmative action policy.

The Michigan construction industry is the focus of this study. This study examined not only these employment outcome benefits, but also outlines the outcome benefit trends over thirty-one years for national employment and employment in the state of Michigan with an emphasis on the construction industry. Details regarding white-collar and blue-collar occupational grouping trends as well as unemployment …


Study Of Architecture And Protocols For Reliable Multicasting In Packet Switching Networks, Shiwen Chen May 2000

Study Of Architecture And Protocols For Reliable Multicasting In Packet Switching Networks, Shiwen Chen

Dissertations

Group multicast protocols have been challenged to provide scalable solutions that meet the following requirements: (i) reliable delivery from different sources to all destinations within a multicast group; (ii) congestion control among multiple asynchronous sources. Although it is mainly a transport layer task, reliable group multicasting depends on routing architectures as well.

This dissertation covers issues of both network and transport layers. Two routing architectures, tree and ring, are surveyed with a comparative study of their routing costs and impact to upper layer performances. Correspondingly, two generic transport protocol models are established for performance study. The tree-based protocol is rate-based …


Intermodal Transit System Coordination With Dynamic Vehicle Dispatching, Md. Shoaib Chowdhury May 2000

Intermodal Transit System Coordination With Dynamic Vehicle Dispatching, Md. Shoaib Chowdhury

Dissertations

In most urban areas where transit demand is spread widely, passengers may be served by an intermodal transit system, consisting of a rail transit line (or a bus rapid transit route) and a numbers of feeder routes connecting at different transfer stations. In such a system, passengers may need one or more transfers to complete their journey. Therefore, scheduling vehicles operating in the system with special attention to reduce transfer time can contribute significantly service quality improvements. In this study two models, one for coordination of a general intermodal. transit system and another for dynamic dispatching of vehicles on coordinated …


Time Domain Measurement Of The Nonlinear Refractive Index In Optical Fibers And Semiconductor Film, Hernando Garcia May 2000

Time Domain Measurement Of The Nonlinear Refractive Index In Optical Fibers And Semiconductor Film, Hernando Garcia

Dissertations

A new technique to measure the nonlinear refractive index n2 in optical fibers and semiconductor films has been developed. It is based on the time delay two-beam coupling of very intense picosecond laser pulses that have been self-phase modulated in the nonlinear optical medium. The two beams are coupled in a slow responding medium that is sensitive to time dependent phase distortions. We determine that the amount of phase distortion experienced by the pulse is proportional to the nonlinear refractive index of the medium, This time domain approach can also be applied to optical fiber amplifiers in the presence …


Genetically Evolved Dynamic Control For Quadruped Walking, Giorgio Grasso May 2000

Genetically Evolved Dynamic Control For Quadruped Walking, Giorgio Grasso

Dissertations

The aim of this dissertation is to show that dynamic control of quadruped locomotion is achievable through the use of genetically evolved central pattern generators. This strategy is tested both in simulation and on a walking robot. The design of the walker has been chosen to be statically unstable, so that during motion less than three supporting feet may be in contact with the ground.

The control strategy adopted is capable of propelling the artificial walker at a forward locomotion speed of ~1.5 Km/h on rugged terrain and provides for stability of motion. The learning of walking, based on simulated …


A Meta-Semantic Language For Smart Component-Adapters, Leon K. Jololian May 2000

A Meta-Semantic Language For Smart Component-Adapters, Leon K. Jololian

Dissertations

The issues confronting the software development community today are significantly different from the problems it faced only a decade ago. Advances in software development tools and technologies during the last two decades have greatly enhanced the ability to leverage large amounts of software for creating new applications through the reuse of software libraries and application frameworks. The problems facing organizations today are increasingly focused around systems integration and the creation of information flows.

Software modeling based on the assembly of reusable components to support software development has not been successfully implemented on a wide scale. Several models for reusable software …


Endotoxin Removal From Protein Solutions By Immobilized Metal Ion Affinity Chromatography, Yun Kang May 2000

Endotoxin Removal From Protein Solutions By Immobilized Metal Ion Affinity Chromatography, Yun Kang

Dissertations

In the biotechnology/pharmaceutical industry, the removal of endotoxins from final protein product has always been a challenge. A novel method for endotoxin removal from protein solutions, immobilized metal (ion) affinity chromatography (IMAC) has been developed in this study. Fe3+ was charged to a chelating gel that contains iminodiacetic acid (IDA). The IDA- Fe3+ IMAC column was exploited to remove endotoxin from protein solutions. This method involves the adsorption of the endotoxin on IMAC column. More than 99% endotoxin is removed and protein yield is higher than 90%. IDA-Fe3+ IMAC has proved to be an economical and efficient …


Active Feedback Control Of A Wake Flow Via Forced Oscillations Based On A Reduced Model, Fu Li May 2000

Active Feedback Control Of A Wake Flow Via Forced Oscillations Based On A Reduced Model, Fu Li

Dissertations

As it is well known, the flow past a cylinder consists of a symmetric recirculation bubble of vortices at small Reynolds numbers. As Reynolds number increases, the bubble becomes unstable and develops into a Karman vortex street of alternating vortices. This instability is responsible for the occurrence of large amplitude oscillations in the lift and an increase in the mean drag. It was previously shown by numerical simulation that the mechanism driving the bubble instability is well mimicked by Foppl's four dimensional potential flow model where the bubble is represented by a saddle point. In this work, we design two …


Video Traffic Modeling And Delivery, Hai Liu May 2000

Video Traffic Modeling And Delivery, Hai Liu

Dissertations

Video is becoming a major component of the network traffic, and thus there has been a great interest to model video traffic. It is known that video traffic possesses short range dependence (SRD) and long range dependence (LRD) properties, which can drastically affect network performance. By decomposing a video sequence into three parts, according to its motion activity, Markov-modulated self-similar process model is first proposed to capture autocorrelation function (ACF) characteristics of MPEG video traffic. Furthermore, generalized Beta distribution is proposed to model the probability density functions (PDFs) of MPEG video traffic.

It is observed that the ACF of MPEG …


Fluidization And Soot Filtration In A Rotating Fluidized Bed, Gui-Hua Qian May 2000

Fluidization And Soot Filtration In A Rotating Fluidized Bed, Gui-Hua Qian

Dissertations

A horizontal rotating fluidized bed (RFB) has been investigated for the removal of soot from diesel engine exhaust. This requires necessitating an understanding of the nature of fluidization, particle mixing and filtration in the RFB.

In an RFB, particles are subject to a centrifugal force which can be much larger than the force of gravity. Therefore the Geldart classification for conventional fluidized beds must be modified for rotating fluidized beds. A theoretical analysis shows that group A particles (minimum bubbling velocity Umb > minimum fluidization velocity Umf can shift to group B Umb = Umf and group …


Virtual Reality Based Creation Of Concept Model Designs For Cad Systems, Bilal Yehya Maiteh May 2000

Virtual Reality Based Creation Of Concept Model Designs For Cad Systems, Bilal Yehya Maiteh

Dissertations

This work introduces a novel method to overcome most of the drawbacks in traditional methods for creating design models. The main innovation is the use of virtual tools to simulate the natural physical environment in which freeform. Design models are created by experienced designers. Namely, the model is created in a virtual environment by carving a work piece with tools that simulate NC milling cutters.

Algorithms have been developed to support the approach, in which the design model is created in a Virtual Reality (VR) environment and selection and manipulation of tools can be performed in the virtual space. The …


Investigation Of The Baroreflex Of The Rat : Steady State And Dynamic Features, Xiaorui Tang May 2000

Investigation Of The Baroreflex Of The Rat : Steady State And Dynamic Features, Xiaorui Tang

Dissertations

The baroreflex is one of the most important feedback systems in the body to maintain blood pressure variation within the homeostatic range. In this dissertation, the important features of the carotid and aortic baroreflexes have been extensively investigated on ventilated, central nervous system intact, neuromuscular blocked (NMB) rats using different control system and signal processing tools. Studies have demonstrated that sinoaortic denervation (SAD) caused substantial increases in the blood pressure variability. Comparing the pre- and post-SAD blood pressure spectra, there was a significant increase of power in the very low frequency region (0.00195 -0.2 Hz), and a significant decrease of …


Rapid Tooling By Integration Of Solid Freedom Fabrication And Electrodepostion, Bo Yang May 2000

Rapid Tooling By Integration Of Solid Freedom Fabrication And Electrodepostion, Bo Yang

Dissertations

Rapid tooling (RT) techniques based on solid freeform fabrication (SFF) are being studied worldwide to speed up the design-production cycle and thus keep manufacturers at a competitive edge. This dissertation presents a novel rapid tooling process that integrates SFF with electrodeposition to produce molds, dies, and electrical discharge machining (EDM) electrodes rapidly, accurately and cost effectively. Experimental investigation, thermornechanical modeling and analysis, as well as case studies reveal that integration of electroforming with solid freeform fabrication is a viable way for metal tool making.

The major research tasks and results of this dissertation study are as follows:

  • Rapid electroforming tooling …


Laminar Viscous Resuspension In Two-Dimensional Channels, Wenyue Yin May 2000

Laminar Viscous Resuspension In Two-Dimensional Channels, Wenyue Yin

Dissertations

The laminar viscous resuspension of sphere particles in two-dimensional channel with gravity and electrostatic effects is studied numerically. The constitutive equation for particles include the shear-induced diffusion flux, gravitational sedimentation flux and electro-static diffusion flux. In addition the continuity equation and the momentum equations for incompressible flow are solved for developing flow using finite element method.

The parameters in this study are ratio of particle diameter to channel height d/h, Reynolds number Re, Froude number Fr, uniform inlet particle volume fraction Φ0, and electrostatic parameter Q. The numerical simulation included d/h from 0.03 to 0.12, Re from 5 …


An Integrated Membrane-Based Chromatographic Process For Biomolecule Isolation And Purification, Xiaoping Dai May 2000

An Integrated Membrane-Based Chromatographic Process For Biomolecule Isolation And Purification, Xiaoping Dai

Dissertations

Biomolecules obtained from fermentation and cell-culture processes are present in low concentrations in a complex medium/broth. For intracellular products, cells are first harvested. Subsequently, cell lysis and homogenization are undertaken to produce a homogenate. The biomolecules are next separated from the cell debris by lysate clarification. For extracellular products, the biomolecules are separated from the whole cells by clarification. The overall yield is reduced with each additional step. As the cost of bioseparation process accounts for 50-80% of the final product cost, innovations in and improvement of bio-downstream processing are greatly needed.

In this research, a cyclic process integrating a …


Applications Of Agent Architectures To Decision Support In Distributed Simulation And Training Systems, Plamen V. Petrov May 2000

Applications Of Agent Architectures To Decision Support In Distributed Simulation And Training Systems, Plamen V. Petrov

Dissertations

This work develops the approach and presents the results of a new model for applying intelligent agents to complex distributed interactive simulation for command and control. In the framework of tactical command, control communications, computers and intelligence (C4I), software agents provide a novel approach for efficient decision support and distributed interactive mission training. An agent-based architecture for decision support is designed, implemented and is applied in a distributed interactive simulation to significantly enhance the command and control training during simulated exercises. The architecture is based on monitoring, evaluation, and advice agents, which cooperate to provide alternatives to the …


Simulation And Modeling Of Magnetically-Assisted Impaction Coating (Maic) Process For Dry Particle Coating, Bodhisattwa Chaudhuri May 2000

Simulation And Modeling Of Magnetically-Assisted Impaction Coating (Maic) Process For Dry Particle Coating, Bodhisattwa Chaudhuri

Dissertations

The objective of proposed research is to model, and understand the processes happening at multiple length and time scales in magnetically assisted impaction coating process. The smallest length scale is of the order of the molecular size and is important because during collisions the molecules rearrange themselves to form a semi-permanent bond between the core and secondary particles, which is studied by using the results of direct numerical integration of the governing Newton's equations. The effect of parameters such as size, orientation and relative velocity of particles on the collision mechanics is quantified. The largest length scale which is the …


Design And Analysis Of A Scalable Terabit Multicast Packet Switch : Architecture And Scheduling Algorithms, Feihong Chen May 2000

Design And Analysis Of A Scalable Terabit Multicast Packet Switch : Architecture And Scheduling Algorithms, Feihong Chen

Dissertations

Internet growth and success not only open a primary route of information exchange for millions of people around the world, but also create unprecedented demand for core network capacity. Existing switches/routers, due to the bottleneck from either switch architecture or arbitration complexity, can reach a capacity on the order of gigabits per second, but few of them are scalable to large capacity of terabits per second.

In this dissertation, we propose three novel switch architectures with cooperated scheduling algorithms to design a terabit backbone switch/router which is able to deliver large capacity, multicasting, and high performance along with Quality of …


A Study Of Droplet Burning In The Nearly Adiabatic Limit, Juan C. Gomez May 2000

A Study Of Droplet Burning In The Nearly Adiabatic Limit, Juan C. Gomez

Dissertations

We consider a small drop of liquid fuel that burns in an oxidizing gaseous environment and translates slowly (relative to flow 'at infinity') under the action of gravity. Practical applications include the burning of liquid fuels as sprays in domestic and industrial oil-fired burners, diesel engines, and liquid-propellant rocket motors. More relevant to the simple physical set-up of the present study are wellcharacterized laboratory experiments on the burning of a single, isolated fuel drop.

The drop burns in a nearly spherical, diffusion flame, flame sheet regime. We consider a specific example, or limit, referred to as 'nearly adiabatic burning', in …


Numerical Study Of Particle Dynamics In A Falling-Ball Viscometer, Peiwen Hou May 2000

Numerical Study Of Particle Dynamics In A Falling-Ball Viscometer, Peiwen Hou

Dissertations

The falling-ball viscometer is a device where a spherical particle falls along the axis of a circular cylinder filled with viscous fluid. The various classical results for this device are developed under the assumption that the Reynolds number of the flow is zero, i.e., Stoke's flow. Inertial effects are not taken into account. To better understand the dynamics of the particle sedimentation process and the role of inertia in this process, we implemented a numerical simulation.

The ADI (Alternating Direction Implicit) scheme is widely used to solve the vorticity-stream function formulation of the Navier-Stokes equation in axisymmetric geometries. However, a …