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Protein And Endotoxin Interactions And Endotoxin Removal From Protein Solutions, Liping Li Aug 1999

Protein And Endotoxin Interactions And Endotoxin Removal From Protein Solutions, Liping Li

Dissertations

The investigation objectives of this study include: endotoxin disaggregation by proteins; protein concentration effect on protein-endotoxin binding and endotoxin removal; size exclusion high performance liquid chromatography (SE-HPLC) studies on endotoxin dissociation by bovin serum albumin (BSA); use of Ca+2 to re-aggregate endotoxin in hemoglobin solutions and the subsequent removal of endotoxin by ultrafiltration; quantitative determination of Ca+2 effects on endotoxin removal and protein yield in a two-stage ultrafiltration.

It is known that some proteins can disaggregate endotoxins and form complexes with lipopolysaccharides (LPS). It is also known that Ca can act as "bridges" to aggregate LPS in aqueous …


Evaluation Of Raman Spectroscopy And Ruby Piezospectroscopy As Tools For Investigating The Corrosion Of Metallic Alloys, Daniel P. Renusch Aug 1999

Evaluation Of Raman Spectroscopy And Ruby Piezospectroscopy As Tools For Investigating The Corrosion Of Metallic Alloys, Daniel P. Renusch

Dissertations

Stainless steel system components that operate in high temperature oxidizing environments obtain protection from corrosion by means of thermally grown chromia and alumina scales. Ongoing investigations of protective scales utilize a battery of experimental and theoretical techniques. A technique which has received little attention is Raman scattering. The reason for its limited use has been long data acquisition times required to obtain suitable spectra from thin surface oxides. Because advances in detection systems, namely the multichannel CCD (charge coupled devices), have recently provided dramatic improvement in the sensitivity of Raman scattering experiments, we decided to reevaluate the technique as a …


Active Local Volume Displacement Cancellation Of A Vibrating Baffled Beam, Marcellin Zahui Aug 1999

Active Local Volume Displacement Cancellation Of A Vibrating Baffled Beam, Marcellin Zahui

Dissertations

An active noise control apparatus is developed. The device reduces the sound radiated from a vibrating clamped beam. The attenuation of the sound field is obtained through minimization of local volume displacements of the vibrating beam. Two single-input/single-output cancellation devices are used. Each device employs a motion sensor and an acoustic actuator. The actuator is a loudspeaker equipped with a pressure sensor to detect its volume displacement. The motion sensor signal is related to the local volume displacement of the structure which is then reduced by a loudspeaker driven with an equal but opposing volume displacement. The volume displacement sensors …


Improving Special Education Teachers' Use Of Data-Based Instruction, Steven D. Goodman Jun 1999

Improving Special Education Teachers' Use Of Data-Based Instruction, Steven D. Goodman

Dissertations

The data-based decision model involves frequent measures of student performance (i.e., 2 - 5 times per week), frequent analysis of performance data (weekly or bi-weekly), and the application of decision rules. In the first study, we surveyed 406 special education teachers state-wide. Results of the survey suggest that the databased decision model is not generally practiced by special educators in the field. Just over one quarter of the respondents report to assessing student performance frequently enough to qualify as using the model. Only 10% of respondents indicate that they generally graph student performance. Additionally, less than 23% of respondents who …


Adaptive Interference Cancelation Techniques For Multicarrier Modulated Systems, Matthijs A. Visser May 1999

Adaptive Interference Cancelation Techniques For Multicarrier Modulated Systems, Matthijs A. Visser

Dissertations

Current wireline systems and wireless broadcasting systems employ multicarrier modulation (MCM). This includes the high-rate digital subscriber line (HDSL), digital audio broadcasting system (DAB) and the digital terrestrial television broadcasting system (dTTb). Multicarrier modulation is also envisioned for high-speed indoor wireless local area networks (WLAN). Additionally, multicarrier code division multiple access (MC-CDMA), a hybrid of orthogonal frequency division multiplexing (OFDM) and CDMA, is proposed for the downlink (base-to-mobile) of a 3rd generation wireless system as part of the IMT-2000 standardization process.

The performance of an MC-CDMA system--similar to a direct sequence CDMA (DS-CDMA) system--is limited by the presence of multiple …


Cadmium, Chromium And Lead In Environmental Samples : Speciation And Determination, Hsing-Hui Yu May 1999

Cadmium, Chromium And Lead In Environmental Samples : Speciation And Determination, Hsing-Hui Yu

Dissertations

Heavy metals are important contaminants in many environmental media. This work focuses on the improvement of current methods for water and sediment analysis for three metals, cadmium, chromium and lead. Batch ion exchange was used for water speciation and a microwave assisted sequential extraction scheme was developed for sediment characterization. The developed methods were applied to a group of environmental samples.

The exchangeable species of these metals in water were preconcentrated on ion exchange resins. These include the bioavailable free ions and weakly complexed ions. Metals sorbed on particles and strongly complexed ions, less bioavailable, were eliminated. The method was …


Applications Of A Microtrap For On-Line Monitoring Of Volatile Organics, Chaohua Feng May 1999

Applications Of A Microtrap For On-Line Monitoring Of Volatile Organics, Chaohua Feng

Dissertations

Microtrap is made by packing a narrow metal tubing with adsorbents. The advantage of a microtrap is that it can be heated and cooled in the order of seconds. It has been used previously as a concentration cum injection device for on-line gas chromatography and also monitoring non-methane organic carbon in air emissions. In this research breakthrough and desorption characteristics of the microtrap were studied. A two-stage microtrap system was developed to reduce breakthrough while making sharp injection for GC separation. Microtrap was also used as a concentrator cum injector in on-line mass spectrometry. Finally, a microtrap based, continuous non-methane …


Development Of Membrane Extraction Systems For Measuring Trace Level Organic Compounds In Water, Xuemei Guo May 1999

Development Of Membrane Extraction Systems For Measuring Trace Level Organic Compounds In Water, Xuemei Guo

Dissertations

The presence of volatile organic compounds (VOCs) in ground and surface water resources poses a threat to public health. The measurement of these trace level contaminants in water is of significant importance. Conventional methods for analysis of trace volatile organic compounds in water include purge and trap, head space analysis, and solid phase microextraction (SPME). While these are excellent laboratory techniques, none of them can be used for continuous, on-line monitoring of water streams. Membrane separation of organic compounds from water provides an exciting possibility for on-line extraction and analysis. In previous investigations, water continuously flowed on the feed side …


Chemical Reactions And Mass Transport In Emulsion Liquid Membrane, Huifang Fan May 1999

Chemical Reactions And Mass Transport In Emulsion Liquid Membrane, Huifang Fan

Dissertations

Emulsion liquid membrane (ELM) systems are an important technique for wastewater cleanup. For this purpose, emulsion globules are dispersed in wastewater (external phase), each emulsion globule consisting of many tiny aqueous droplets (internal phase) enclosed in oil (membrane phase). Hazardous chemicals in the wastewater are transported into the internal droplets by mass transfer mechanisms.

Since Li first invented an ELM system in the 1960s, much research effort has been devoted to experimentally finding the optimal conditions for ELM recovery of various chemicals. Such studies would have benefited greatly from the guidance of mathematical models, especially those that provide analytical predictions. …


Long Term Risks Associated With Brownfield Containments, Shailesh Shirish Chirputkar May 1999

Long Term Risks Associated With Brownfield Containments, Shailesh Shirish Chirputkar

Dissertations

The sites at which the development is hindered by real or perceived contamination are called as Brownfield sites. It is a common trend in industry to develop these types of sites with surface and peripheral containments. It might prove unwise to develop the sites in this manner from a long term perspective without considering the associated risk. Because of this, a model has been proposed for long term risk assessments of brownfield containments.

Objectives of this study were to develop a contaminant transport model for flow of contaminants towards the surface and peripheral containments inside the site, a model for …


Utilization Of Processed Fly Ash In Mortar, Walairat Bumrongjaroen May 1999

Utilization Of Processed Fly Ash In Mortar, Walairat Bumrongjaroen

Dissertations

Grinding process is introduced to provide fine particles of coal fly ash that enhances the strength gain of cement mortars. It is discovered that grinding can make all the studied fly ashes more suitable for concrete use at higher replacement value than previously anticipated even when the effect of high carbon content is considered.

In this study, new mechanisms for strength gain of fly ash mortars are proposed. They are dispersion and nucleation, which are results from the presence of fly ash in the cement mortar. These effects are shown to enhance the hydration of cement. The pozzolanic action of …


Developing Techniques For Enhancing Comprehensibility Of Controlled Medical Terminologies, Huanying Gu May 1999

Developing Techniques For Enhancing Comprehensibility Of Controlled Medical Terminologies, Huanying Gu

Dissertations

A controlled medical terminology (CMT) is a collection of concepts (or terms) that are used in the medical domain. Typically, a CMT also contains attributes of those concepts and/or relationships between those concepts. Electronic CMTs are extremely useful and important for communication between and integration of independent information systems in healthcare, because data in this area is highly fragmented. A single query in this area might involve several databases, e.g., a clinical database, a pharmacy database, a radiology database, and a lab test database.

Unfortunately, the extensive sizes of CMTs, often containing tens of thousands of concepts and hundreds of …


Porting The Sisal Functional Language To Distributed-Memory Multiprocessors, Jui-Yuan Ku May 1999

Porting The Sisal Functional Language To Distributed-Memory Multiprocessors, Jui-Yuan Ku

Dissertations

Parallel computing is becoming increasingly ubiquitous in recent years. The sizes of application problems continuously increase for solving real-world problems. Distributed-memory multiprocessors have been regarded as a viable architecture of scalable and economical design for building large scale parallel machines. While these parallel machines can provide computational capabilities, programming such large-scale machines is often very difficult due to many practical issues including parallelization, data distribution, workload distribution, and remote memory latency.

This thesis proposes to solve the programmability and performance issues of distributed-memory machines using the Sisal functional language. The programs written in Sisal will be automatically parallelized, scheduled and …


A Methodology For Solving The Network Toll Design Problem, Mei Chen May 1999

A Methodology For Solving The Network Toll Design Problem, Mei Chen

Dissertations

Congestion pricing has been regarded as an efficient method to reduce network-wide travel cost. In this dissertation, a methodology for toll design is developed to provide policy-makers with suggestions on both where to charge tolls and how much the tolls should be. As opposed to the traditional approach of marginal social cost pricing, this methodology is capable of dealing with the more realistic case, in which only a small number of links can be tolled. Furthermore, this methodology is expanded to accommodate multiple user groups.

The toll design problem can be formulated using both deterministic and stochastic route choice models. …


Physical And Geotechnical Characterization Of Water Treatment Plant Residuals, Swamy C. Basim May 1999

Physical And Geotechnical Characterization Of Water Treatment Plant Residuals, Swamy C. Basim

Dissertations

The study of Water Treatment Plant (WTP) residuals is of recent origin and very little information is available in literature regarding these residuals. These waste materials have high solids contents, even in the mechanically dewatered condition, making it difficult to handle. These, along with stringent environmental regulations have forced the water utilities to look for new disposal options for these residuals. For this purpose as well as for evaluating suitable options for the beneficial reuse of residuals, it is essential to characterize WTP residuals.

As the dewatered residuals are plastic, the researcher may be prompted to treat these materials as …


Flame Dynamics In Steady Strained Flows, Zili Huang May 1999

Flame Dynamics In Steady Strained Flows, Zili Huang

Dissertations

In this dissertation, the response of a premixed flame to time-dependent strained flow fields is investigated. Because of the potential application to turbulent combustion modeling, the main focus is on the particular case of a flame in stagnation point flow with an imposed oscillatory strain rate. The flame is modeled as a hydrodynamic discontinuity separating burned from unburned gasses. To complete the formulation of the problem, conditions relating the fluid variables across the flame front are needed, as is a flame speed equation that determines the evolution of the discontinuity. These conditions are derived through asymptotic analysis of the flame …


Dynamical Systems Associated With Particle Flow Models : Theory And Numerical Methods, Roman V. Samulyak May 1999

Dynamical Systems Associated With Particle Flow Models : Theory And Numerical Methods, Roman V. Samulyak

Dissertations

A new class of integro - partial differential equation models is derived for the prediction of granular flow dynamics. These models are obtained using a novel limiting averaging method (inspired by techniques employed in the derivation of infinite-dimensional dynamical systems models) on the Newtonian equations of motion of a many-particle system incorporating widely used inelastic particle-particle force formulas. By using Taylor series expansions, these models can be approximated by a system of partial differential equations of the Navier-Stokes type. Solutions of the new models for granular flows down inclined planes and in vibrating beds are compared with known experimental and …


On Scheduling Input Queued Cell Switches, Shizhao Li May 1999

On Scheduling Input Queued Cell Switches, Shizhao Li

Dissertations

Output-queued switching, though is able to offer high throughput, guaranteed delay and fairness, lacks scalability owing to the speed up problem. Input-queued switching, on the other hand, is scalable, and is thus becoming an attractive alternative. This dissertation presents three approaches toward resolving the major problem encountered in input-queued switching that has prohibited the provision of quality of service guarantees.

First, we proposed a maximum size matching based algorithm, referred to as min-max fair input queueing (MFIQ), which minimizes the additional delay caused by back pressure, and at the same time provides fair service among competing sessions. Like any maximum …


On-Line State And Parameter Estimation In Nonlinear Systems, David A. Haessig May 1999

On-Line State And Parameter Estimation In Nonlinear Systems, David A. Haessig

Dissertations

On-line, simultaneous state and parameters estimation in deterministic, nonlinear dynamic systems of known structure is the problem considered. Available methods are few and fall short of user needs in that they are difficult to apply, their applicability is restricted to limited classes of systems, and for some, conditions guaranteeing their convergence don't exist.

The new methods developed herein are placed into two categories: those that involve the use of Riccati equations, and those that do not. Two of the new methods do not use Riccati equations, and each is considered to be a different extension of Friedland' s parameter observer …


Automatic Document Classification And Extraction System (Adoces), Xuhong Li May 1999

Automatic Document Classification And Extraction System (Adoces), Xuhong Li

Dissertations

Document processing is a critical element of office automation. Document image processing begins from the Optical Character Recognition (OCR) phase with complex processing for document classification and extraction. Document classification is a process that classifies an incoming document into a particular predefined document type. Document extraction is a process that extracts information pertinent to the users from the content of a document and assigns the information as the values of the “logical structure” of the document type. Therefore, after document classification and extraction, a paper document will be represented in its digital form instead of its original image file format, …


Optimization Of Urban Traffic Control Strategies By A Network Design Model, Wu Sun May 1999

Optimization Of Urban Traffic Control Strategies By A Network Design Model, Wu Sun

Dissertations

The efficiency of congested urban transportation networks can be improved by implementing appropriate traffic control strategies, such as signal control timing, turning movement control; implementation of one-way traffic policies, lane distribution controls etc.. In this dissertation, the following strategies are addressed: 1) Intersection left turn addition/deletion, 2) Lane designation,. and 3) Signal optimization.

The analogy between the network design problem (NDP) and the optimization of traffic control strategies motivated the formulation of an urban transportation network design problem (UTNDP) to optimize traffic control strategies. An UTNDP is a typical bi-level programming program, where the lower level problem is a User …


Knowledge Management For Texpros, Jianshun Hu May 1999

Knowledge Management For Texpros, Jianshun Hu

Dissertations

Most of the document processing systems today have applied Al technologies to support their system intelligent behaviors. For the application of Al technologies in such systems, the core problem is how to represent and manage different kinds of knowledge to support their inference engine components' functionalities. In other words, knowledge management has become a critical issue in the document processing systems. In this dissertation, within the scope of the TEXt PROcessing System (TEXPROS), we identify knowledge of various kinds that are applicable in the system. We investigate several problems of managing this knowledge and then develop a knowledge base for …


Development Of Computer Model And Expert System For Pneumatic Fracturing Of Geologic Formations, Brian Michael Sielski May 1999

Development Of Computer Model And Expert System For Pneumatic Fracturing Of Geologic Formations, Brian Michael Sielski

Dissertations

The objective of this study was the development of a new computer program called PF-Model to analyze pneumatic fracturing of geologic formations. Pneumatic fracturing is an in situ remediation process that involves injecting high pressure gas into soil or rock matrices to enhance permeability, as well as to introduce liquid and solid amendments. PF-Model has two principal components: (1) Site Screening, which heuristically evaluates sites with regard to process applicability; and (2) System Design, which uses the numerical solution of a coupled algorithm to generate preliminary design parameters.

Designed as an expert system, the Site Screening component is a high …


Fdtd-Based Full Wave Co-Simulation Model For Hybrid Electromagnetic Systems, Tong Li May 1999

Fdtd-Based Full Wave Co-Simulation Model For Hybrid Electromagnetic Systems, Tong Li

Dissertations

In high-frequency ranges, the present electronic design automation software has limited capabilities to model electromagnetic (EM) systems where there are strong field effects influencing their characteristics. In this situation, a full-wave simulation tool is desired for the analysis and design of high-speed and non-linear EM systems. It is necessary to explore the interaction between the field and electronic components during a transient process when field effects are more significant. The finite-difference time-domain (FDTD) technique receives growing attention in the area of EM system analysis and simulation due to its simplicity, flexibility and robustness. It is a full-wave simulation method that …


Pattern Discovery In Trees : Algorithms And Applications To Document And Scientific Data Management, Chia-Yo Chang May 1999

Pattern Discovery In Trees : Algorithms And Applications To Document And Scientific Data Management, Chia-Yo Chang

Dissertations

Ordered, labeled trees are trees in which each node has a label and the left-to-right order of its children (if it has any) is fixed. Such trees have many applications in vision, pattern recognition, molecular biology and natural language processing.

In this dissertation we present algorithms for finding patterns in the ordered labeled trees. Specifically we study the largest approximately common substructure (LACS) problem for such trees. We consider a substructure of a tree T to be a connected subgraph of T. Given two trees T1, T2 and an integer d, the LACS problem is to find …


Observers For Discrete-Time Nonlinear Systems, Walter D. Grossman May 1999

Observers For Discrete-Time Nonlinear Systems, Walter D. Grossman

Dissertations

Observer synthesis for discrete-time nonlinear systems with special applications to parameter estimation is analyzed. Two new types of observers are developed. The first new observer is an adaptation of the Friedland continuous-time parameter estimator to discrete-time systems. The second observer is an adaptation of the continuous-time Gauthier observer to discrete-time systems. By adapting these observers to discrete-time continuous-time parameter estimation problems which were formerly intractable become tractable.

In addition to the two newly developed observers, two observers already described in the literature are analyzed and deficiencies with respect to noise rejection are demonstrated. improved versions of these observers are proposed …


A New-Generation Class Of Parallel Architectures And Their Performance Evaluation, Qian Wang May 1999

A New-Generation Class Of Parallel Architectures And Their Performance Evaluation, Qian Wang

Dissertations

The development of computers with hundreds or thousands of processors and capability for very high performance is absolutely essential for many computation problems, such as weather modeling, fluid dynamics, and aerodynamics. Several interconnection networks have been proposed for parallel computers. Nevertheless, the majority of them are plagued by rather poor topological properties that result in large memory latencies for DSM (Distributed Shared-Memory) computers. On the other hand, scalable networks with very good topological properties are often impossible to build because of their prohibitively high VLSI (e.g., wiring) complexity. Such a network is the generalized hypercube (GH). The GH supports full-connectivity …


The Field Study Of A Training Transfer Enhancement Process And Its Effect On Transfer Of Training, Andrew W. Bowne Apr 1999

The Field Study Of A Training Transfer Enhancement Process And Its Effect On Transfer Of Training, Andrew W. Bowne

Dissertations

Transfer of training is defined as the degree to which trainees apply, in their jobs, the knowledge, skills, and attitudes they gained in training. Research regarding transfer of training has called training effectiveness into question. For example, Baldwin and Ford (1988) reported average transfer rates typically in the 10% range.

The study tested the effectiveness of particular procedures and tools intended to enhance transfer of training. These transfer enhancing tools were employed by an experimental group of trainees’ supervisors (who received training from the researcher in the application of the tools) before a half-day problem-solving training workshop for their employees …


The Relationship Between Selected Environmental Variables And Attrition, Persistence, And Academic Success Of Majority And Minority College Students, Carole J. Woolford-Hunt Apr 1999

The Relationship Between Selected Environmental Variables And Attrition, Persistence, And Academic Success Of Majority And Minority College Students, Carole J. Woolford-Hunt

Dissertations

Research indicates that college student persistence, attrition, and success is related to the student’s ability to gain academic and social integration into the university community. This theory has guided researchers to explore either the academic or social factors that promote integration. Under the umbrella of social integration exists the underresearched category of environmental factors.

The overall purpose of this study was to identify selected environmental factors that affect minority and majority students’ persistence and success rates in a Midwestern state-run university. The environmental variables of size of college within a larger university, residential versus nonresidential nature of colleges within a …


A Novel Readout Method For Focal Plane Array Imaging In The Presence Of Large Dark Current, Changqing Qiu Jan 1999

A Novel Readout Method For Focal Plane Array Imaging In The Presence Of Large Dark Current, Changqing Qiu

Dissertations

This research was an investigation of a novel readout method for focal plane array (FPA) optical imaging, especially for very sensitive detectors with large dark current. The readout method is based on periodically blocking the optical input enabling the removal of the dark current integration from the output. The research demonstrated that it is feasible to modulate the optical input with the designed readout circuit and thus achieve longer signal integration time to enhance the signal-to-noise ratio.

Study of a proposed circuit model showed that in theory the correlated readout method could increase the output voltage swing and reduce the …