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Gated Multi-Cycle Integration (Gmci) For Focal Plane Array (Fpa) Applications, Haijiang Ou May 2001

Gated Multi-Cycle Integration (Gmci) For Focal Plane Array (Fpa) Applications, Haijiang Ou

Dissertations

In this thesis, the model and the theory of gated multi-cycle integration (GMCI) were first developed specifically for focal plane array dealing with repetitive or modulated image. The operational modes of GMCI include gated integration (GI), phase sensitive integration (PSI), multi-point summation, multi-point subtraction, multi-sample averaging and some of their combinations. Thus, the analytic theory of GMCI somehow unifies the theories of gated integration, phase sensitive detection, multiple summation and average. PSI works with background and/or dark current subtraction. As a result, the storage well of a pixel is mainly used for signal integration even if there exists a strong …


Modeling, Design And Scheduling Of Computer Integrated Manufacturing And Demanufacturing Systems, Ying Tang May 2001

Modeling, Design And Scheduling Of Computer Integrated Manufacturing And Demanufacturing Systems, Ying Tang

Dissertations

This doctoral dissertation work aims to provide a discrete-event system-based methodology for design, implementation, and operation of flexible and agile manufacturing and demanufacturing systems. After a review of the current academic and industrial activities in these fields, a Virtual Production Lines (VPLs) design methodology is proposed to facilitate a Manufacturing Execution System integrated with a shop floor system. A case study on a back-end semiconductor line is performed to demonstrate that the proposed methodology is effective to increase system throughput and decrease tardiness. An adaptive algorithm is proposed to deal with the machine failure and maintenance. To minimize the environmental …


Transit Productivity Analysis In Heterogeneous Conditions Using Data Envelopment Analysis With An Application To Rail Transit, Manuel J. Martinez May 2001

Transit Productivity Analysis In Heterogeneous Conditions Using Data Envelopment Analysis With An Application To Rail Transit, Manuel J. Martinez

Dissertations

This dissertation extends transit productivity analysis by developing a new method of Data Envelopment Analysis (DEA), the linear programming approach to productivity analysis. The new model analyzes productivity of transit working under heterogeneous operating conditions. It is named Two-Farrell DEA for it applies DEA in two stages, DEA (1), that calculates the productivity frontiers at given operating conditions and DEA (2), that uses inputs adjusted by multipliers calculated in DEA (l). The model Two Farrell DEA calculated productivity benchmarks for each rail transit agency and estimated its potential for higher revenue or lower expense improvement. Additionally, the results identify two …


A Near-Infrared Filter System And Study Of Solar Umbral Dots At 1.6 Μm, Jingshan Wang May 2001

A Near-Infrared Filter System And Study Of Solar Umbral Dots At 1.6 Μm, Jingshan Wang

Dissertations

The observations of solar magnetic fields are very important because they influence events on the sun. Almost all of magnetographs in the world work in the visible wavelength and they are powerful instruments for measuring strong magnetic fields (above 1000 Gauss) on the sun. To measure the weak solar magnetic fields (below 1000 Gauss), a new filter system (magnetograph) working in near-IR wavelength has been developed in this work. This system includes an interference prefilter (FWHM - 40Å), a liquid crystal magnetic analyzer, a near-IR bireffingent filter (FWHM - 2.5Å), a near-IR Fabry-Perot filter (FWHM - 0.12Å), a near-IR InGaAs …


Joint Source Channel Coding For Progressive Image Transmission, Minyi Zhao May 2001

Joint Source Channel Coding For Progressive Image Transmission, Minyi Zhao

Dissertations

Recent wavelet-based image compression algorithms achieve best ever performances with fully embedded bit streams. However, those embedded bit streams are very sensitive to channel noise and protections from channel coding are necessary. Typical error correcting capability of channel codes varies according to different channel conditions. Thus, separate design leads to performance degradation relative to what could be achieved through joint design. In joint source-channel coding schemes, the choice of source coding parameters may vary over time and channel conditions. In this research, we proposed a general approach for the evaluation of such joint source-channel coding scheme. Instead of using the …


Software And Hardware Improvements For Digital Solar Magnetograph System, Shu Yang May 2001

Software And Hardware Improvements For Digital Solar Magnetograph System, Shu Yang

Dissertations

Digital solar imaging systems have been widely used in solar observations. Their high resolution, high rate of image acquisition and convenience for off-line image processing have provided significant improvements to solar physics research. In this project, two digital magnetograph systems established at Big Bear Solar Observatory (BBSO) have been described. One is used to provide a high frame rate magnetogram system, and the other provides a real-time image alignment, i.e., a correlation tracker system.

The developed correlation tracker system consists of a high-speed 64x64 CCD camera, an EDT image grabbing board, an agile mirror, a D/A board and a Sun …


Novel Multiuser Detection And Multi-Rate Schemes For Multi-Carrier Cdma, Pingping Zong May 2001

Novel Multiuser Detection And Multi-Rate Schemes For Multi-Carrier Cdma, Pingping Zong

Dissertations

A large variety of services is [sic] expected for wireless systems, in particular, high data rate services, such as wireless Internet access. Users with different data rates and quality of service (QoS) requirements must be accommodated. A suitable multiple access scheme is key to enabling wireless systems to support both the high data rate and the integrated multiple data rate transmissions with satisfactory performance and flexibility. A multi-carrier code division multiple access (MC-CDMA) scheme is a promising candidate for emerging broadband wireless systems. MC-CDMA is a hybrid of orthogonal frequency division multiplexing (OFDM) and code division multiple access (CDMA). The …


A Software System For Large-Scale Structural Optimization, Keith M. Macbain May 2001

A Software System For Large-Scale Structural Optimization, Keith M. Macbain

Dissertations

This work is driven by recent developments in mathematical programming, the state-of-the-art of structural optimization, the spectacular performance of linear programming algorithms, and computer hardware developments which imply that applications of structural optimization might be used commonly in engineering design. Currently, there are few general purpose optimization routines available to the structural engineer and much of the work has addressed specific classes of problems. Further, there is little widespread use of the available routines, partly due to the large amount of familiarity one must have with the specific details of both the problem and the optimization method. In response, it …


Force And Effort Analysis Of Unfastening Actions In Disassembly Processes, Manuela Sonnenberg May 2001

Force And Effort Analysis Of Unfastening Actions In Disassembly Processes, Manuela Sonnenberg

Dissertations

Fastening is the process of connecting one or more parts together with the aid of fastening elements. Unfastening, the reverse of fastening, is the process of separating components from each other by removing or detaching fastening elements. So far, the unfastening process is not well understood, and the analysis about it is not very extensive.

However, the need for disassembly is currently increasing. First, parts have to be taken apart for service and repair, and secondly, for the recycling process. Therefore, there is a need to consider unfastening during the design process in order to enable efficient disassemblies.

The purpose …


The Effects Of Educational Development Plans Motivation To Learn, And Attitudes And Behaviors Toward Learning Among Eighth Graders, Mary Alice Schultz-Krajenta Apr 2001

The Effects Of Educational Development Plans Motivation To Learn, And Attitudes And Behaviors Toward Learning Among Eighth Graders, Mary Alice Schultz-Krajenta

Dissertations

Educational Development Plans (EDP) have been utilized by school students to structure their curricular programs to meet their high school educational outcomes and to align their curriculum with their desired adult roles. The focus of this study was to examine the effects of EDPs on motivation, attitudes and behaviors towards learning.

A total of 342 eighth-grade students participated in this research which utilized a quantitative and a qualitative approach. The quantitative study used existing data obtained from a small Midwest school district. There were 151 students in the treatment group and 191 students in the control group. Scores from the …


A Comparison Of Methods For Detection Of Qualitative Interaction In Multicenter Trials, Boyd Jay Hanson Apr 2001

A Comparison Of Methods For Detection Of Qualitative Interaction In Multicenter Trials, Boyd Jay Hanson

Dissertations

This research evaluated and compared three methods for the detection of qualitative treatment-by-center interaction proposed by Azzalini and Cox, Gail and Simon and Ciminera et al., through the analysis of simulated data for multicenter studies of two and three centers with two treatments. The effect of unequal sample size and the presence of an overall treatment effect on characteristics of the methods were examined.

The approach, underlying assumptions and theory of the three methods differ. For this study, they were adapted to establish a common basis for evaluation, thus allowing a meaningful comparison of the methods. For the test presented …


Study Of Automotive Hydromount Mechanism, Min Lu Apr 2001

Study Of Automotive Hydromount Mechanism, Min Lu

Dissertations

The hydromount mechanism is studied. It was determined that the dynamic characteristics of the hydromounts are related to the rubber static stiffness, rubber damping coefficient, volumetric stiffness, and effectiveness of the oscillating fluid in the inertia track. At high frequencies the motion of the fluid in the inertia track diminishes so that its effect is negligible and may be ignored. It is also concluded that the rubber damping has a minimal effect on the hydromount dynamic properties and may be neglected. The maximum loss angle, which corresponds to the maximum damping coefficient of the hydromount, occurs near the inertia track …


An Analysis Of The Impact Of An Outlier On Correlation Coefficients Across Small Sample Data Where Rho Is Non-Zero, Maria A. Suchowski Apr 2001

An Analysis Of The Impact Of An Outlier On Correlation Coefficients Across Small Sample Data Where Rho Is Non-Zero, Maria A. Suchowski

Dissertations

This study addressed the problem o f the probable effectiveness o f the Pearson correlation coefficient (r) as an estimator o f moderate or strong population correlation (rho) when that estimate is based on small sample data which contains an outlier. In such a situation, three components contribute to the size o f a sample correlation coefficient, and so to the subsequent effectiveness o f the resulting estimation decision. These components are 1) rho, 2) sample size, and 3) outlier. Considered in this study were: two conditions o f rho (.5 and .8), three sample sizes (10, 30 and 50) …


Crossing Myriad Borders: A Dimensional Analysis Of The Migration And Health Experiences Of Indigenous Oaxacan Women, Sharon Mcguire Phd, Op, Msn, Rn-C Mar 2001

Crossing Myriad Borders: A Dimensional Analysis Of The Migration And Health Experiences Of Indigenous Oaxacan Women, Sharon Mcguire Phd, Op, Msn, Rn-C

Dissertations

The growing feminization of the migration of ethnic indigenous women, such as Mixtecs, Zapotecs and Triquis from the southern Mexican state of Oaxaca, are altering the dynamics and configuration of traditional Mexican migration, making it especially significant for the health professions. Informed by a postcolonial ecofeminist paradigm, this bi-national grounded theory study explored the migration and health experiences of indigenous Oaxacan immigrant/migrant women. Data collection using participant observation and interviewing occurred in Oaxaca, Mexico, along the US-Mexico border, and the interior of California. Dimensional analysis was used as the method of data analysis to generate theoretical understandings of these phenomena. …


Phase-Locked Loop, Delay-Locked Loop, And Linear Decorrelating Detector For Asynchronous Multirate Ds-Cdma System, Sok-Kyu Lee Jan 2001

Phase-Locked Loop, Delay-Locked Loop, And Linear Decorrelating Detector For Asynchronous Multirate Ds-Cdma System, Sok-Kyu Lee

Dissertations

The performance of phase synchronization and code tracking of a digital phase-locked loop (PLL) and delay-locked loop (DLL), respectively, is investigated in wideband asynchronous multirate DS-CDMA system. Dynamic Partial Correlation (DPC) method is proposed to evaluate the autocorrelation and its power spectrum density (PSD) of the cross-correlated terms in the presence of multirate multiple access interference (MMAI) under additive white gaussian noise (AWGN) and fading channel environments. The steady-state probability density function (PDF) and variance of the phase estimator error and code tracking jitter is evaluated by solving the first-order Fokker-Planck equation.

Among many linear multiuser detectors which decouple the …


Comparison Of Optical Density, Total Cell Protein, And Number Of Viable Cells (Via Fluorescent Straining) As Measures Of Microbial Growth Kinetics In Suspended And Biofilm Cultures During Biodegradation Of Naphthalene, Jeong Seop Shim Jan 2001

Comparison Of Optical Density, Total Cell Protein, And Number Of Viable Cells (Via Fluorescent Straining) As Measures Of Microbial Growth Kinetics In Suspended And Biofilm Cultures During Biodegradation Of Naphthalene, Jeong Seop Shim

Dissertations

Most studies on bacterial growth kinetics have been dependent on theoretical modeling with general biomass measurements using either dry weight or optical density (OD), without distinguishing live from dead bacteria or debris. As a result, there remains considerable uncertainty in reliably predicting rates of biodegradation for design of treatment processes for environmental pollutants.

This research focused on measurement of bacterial growth rates and activities in suspended cultures and biofilms using Pseudomonas putida (ATCC 17484) for biodegradation of naphthalene. As expected, the rates of biodegradation differed between suspended and immobilized cultures. A comparison was made of the impact of three biomass …


Numerical Stimulation Of Stress-Induced Crystallization Of Injection Molded Semicrystalline Thermoplastics, Jianxin Guo Jan 2001

Numerical Stimulation Of Stress-Induced Crystallization Of Injection Molded Semicrystalline Thermoplastics, Jianxin Guo

Dissertations

Injection molded semicrystalline plastic products exhibit variable morphology along their thickness directions. The processing conditions have a significant effect on the crystallinity distribution in the final parts. However, because of the lack of sound theoretical models for stress-induced crystallization kinetics in thermoplastics, simulations of the injection molding process of semicrystalline plastics with the consideration of stress-induced crystallization have been scarce.

A stress-induced crystallization model for semicrystalline plastics is proposed based on the theory that stress induced orientation of polymer chains increase the melting temperature of the plastics, and hence, the supercooling which is the driving force for crystallization. By assuming …


Numerical Modeling And Optimization Of Waterjet Based Surface Decontamination, Konstantin Babets Jan 2001

Numerical Modeling And Optimization Of Waterjet Based Surface Decontamination, Konstantin Babets

Dissertations

The mission of this study is to investigate the high-pressure waterjet based surface decontamination. Our specific objective is to develop a practical procedure for selection of process conditions at given constraints and available knowledge. This investigation is expected to improve information processing in the course of material decontamination and assist in the implementation of the waterjet decontamination technology into practice. The development of a realistic procedure for processing of a chaotic and non-accurate information constitutes the main accomplishment of this study.

The research involved acquisition of representative information about removal of brittle, elastic and viscous deposits. As a result an …


Empirical Model-Based Control For End Milling Process, Abdelmalak Salib Jan 2001

Empirical Model-Based Control For End Milling Process, Abdelmalak Salib

Dissertations

The main objective of this research is to develop an empirical model-based control mechanism to maintain a fine surface finish quality by maintaining on-line cutting force values. The proposed model has been developed to present the control model constraints, by varying the machining parameters to control the force output to be constant. To relate the surface finish and the cutting force in the end milling machining process, a design of experiment has been conducted to determine the effect of two different materials (aluminium and steel) and the machining parameters (feed rate, spindle speed) at a predefined depth of cut.

Regression …


Electro-Magnetic Control Of Cylinder Wake, Zhihua Chen Jan 2001

Electro-Magnetic Control Of Cylinder Wake, Zhihua Chen

Dissertations

The objective of this dissertation is to develop open and closed-loop control algorithms for manipulating wake flows past a solid cylinder in an electrically low-conducting fluid (e.g. seawater). The intent is to avoid both vortex shedding and flow separation from the body. It is desired to reduce the mean drag significantly and prevent the lift from becoming non-zero at all times. This is achieved through the introduction of a Lorentz force in the azimuthal direction generated by an array of permanent magnets and electrodes located on the solid structure. The array of actuators offers the advantage of making the Lorentz …


Assessing The Economic Impact Of Aircraft Noise On Communities, Ithan B. Zimmer Jan 2001

Assessing The Economic Impact Of Aircraft Noise On Communities, Ithan B. Zimmer

Dissertations

The impact of aircraft noise on communities is complex and multi-dimensional. This matter cannot be resolved without careful analysis of a complex array of related problems and issues including the environment, the economy, and quality-of-life concerns of people living in proximity to airports or aircraft routes. The effects of community noise are widespread and varied. Impacts can include sleep and speech interference, activity interference, general annoyance, and property value decrease. In order to improve public policy and provide a foundation for additional research, it is imperative to establish the extent of a problem. Dollars are often the least common denominator …


Kinematic Synthesis Of Adjustable Spatial Four And Five-Bar Mechanisms For Finite And Multiply Separated Positions, Kevin Russell Jan 2001

Kinematic Synthesis Of Adjustable Spatial Four And Five-Bar Mechanisms For Finite And Multiply Separated Positions, Kevin Russell

Dissertations

Although spatial mechanisms are more general in structure than planar mechanisms, their applications are few due to the limited number of practical design tools and the complexity of those available. It is in fact the task of the future to develop effective, but practical design tools for spatial mechanisms.

This research presents several new methods for synthesizing adjustable spatial mechanisms. The first method involves the kinematic synthesis of spatial mechanisms for multiphase motion generation. Using this method, spatial four and five-bar mechanisms can be synthesized to achieve different phases of prescribed rigid body positions. The theory of this approach has …


Analysis And Control Of Monolithic Piezoelectric Nano-Actuator, Xuemei Sun Jan 2001

Analysis And Control Of Monolithic Piezoelectric Nano-Actuator, Xuemei Sun

Dissertations

The study of the monolithic piezoelectric actuator, the dominant type of micropositioner is an attractive and challenging area, where realtime control theory and digital signal processing are effectively applied. The actuator can be applied in precision instruments and precision control, such as microscopes, medical and optics instruments because of the piezoelectric ceramic's high resolution, fast transient response, and potential low cost. However, hysteresis nonlinearity and lightly damped vibration exist in the system, which limit the actuator applications.

This work focuses on the hysteresis characteristics in time and frequency domains along with experimental and simulated results to verify the effectiveness of …


Environmental Science In The New Millennium : A Model To Give Structure And Guidance, James M. Lipuma Jan 2001

Environmental Science In The New Millennium : A Model To Give Structure And Guidance, James M. Lipuma

Dissertations

This work proposes a template for successful interdisciplinary Environmental Science (EVSQ) programs at four-year American learning institutions. The first conclusion reached is that there is no one "perfect" program. Only by identifying clear goals for EVSC can programs improve. It was determined that a clear definition of EVSC and mission statements related to these definitions are necessary first steps to allow improvement to occur. One major outcome of the work is the educational model built to understand EVSC education. The model identifies methods by which the goals and objectives of EVSC can be identified and accomplished. The research found that …


Multi-Mode Cavity Effects In The Microwave Heating Of A Ceramic Slab, Stuart J. Walker Jan 2001

Multi-Mode Cavity Effects In The Microwave Heating Of A Ceramic Slab, Stuart J. Walker

Dissertations

In order to gain insight into hot spot development in microwave heated ceramics, a partially insulated, two dimensional ceramic slab situated in a TEM01 cavity is modeled in the small Biot number limit. If the electrical conductivity is an exponential function of temperture and E0 is the strength of the incident mode, then the relationship between the spatially uniform, steady state leading order temperature, v8, and E01 is characterized by the well known bi-stable, or S shaped, response curve. The steady state second order temperature, v1, is described by a boundary …


Numerical Studies Of Newtonian And Viscoelastic Fluids, Felix J. Alcocer Jan 2001

Numerical Studies Of Newtonian And Viscoelastic Fluids, Felix J. Alcocer

Dissertations

The direct numerical simulation (DNS) approach is used to understand the flow behavior of Newtonian and viscoelastic fluids in porous materials, four-to-one contraction and the flow of a Newtonian fluid past an airfoil.

In simulations the viscoelastic fluid is modeled by the finitely extensible nonlinear elastic (FENE) dumbbell and Oldroyd-B models. The finite element method (FEM) is used to discretize the flow domain. The DNS results show that the permeability of a periodic porous medium depends on the wavelength used for arranging particles in the direction of flow. Specifically, it is shown that for a given particle size and porosity …


Analysis Of Discrete Dynamical System Models For Competing Species, Jerry J. Chen Jan 2001

Analysis Of Discrete Dynamical System Models For Competing Species, Jerry J. Chen

Dissertations

A discrete version of the Lotka-Volterra (LV) differential equations for competing population species is analyzed in detail, much the same way as the discrete form of the logistic equation has been investigated as a source of bifurcation phenomena and chaotic dynamics. Another related system, namely, the Exponentially Self Regulating (ESR) population model, is also thoroughly analyzed. It is found that in addition to logistic dynamics - ranging from the very simple to manifestly chaotic regimes in terms of the governing parameters - the discrete LV model and the ESR model exhibit their own brands of bifurcation and chaos that are …


A More Efficient Document Retrieval Method For Texpros, Yin Dong Jan 2001

A More Efficient Document Retrieval Method For Texpros, Yin Dong

Dissertations

Document processing is a critical element of office automation. Through document classification, extraction and filing, documents are automatically placed into a knowledge base according to certain rules. Document retrieval is a process to get a document back according to a user's requirements and to show the results to the user. Hence, a good user-interface and an efficient retrieval algorithm become core parts of document retrieval.

Unlike previous browsers that have been proposed for this purpose, this dissertation develops a new browser that has a user interface with more tools, and one that has a more efficient retrieval algorithm that can …


Values Education Influence On Elementary Students' Self-Esteem, Ron W. Germaine Edd Jan 2001

Values Education Influence On Elementary Students' Self-Esteem, Ron W. Germaine Edd

Dissertations

The purpose of this study is to determine if there was a significant difference in measures of self-esteem between elementary school students to whom specific values were formally taught in their school as part of the curriculum and those who did not receive such instruction. The setting for the study was a school district in Canada that had identified sixteen values through community consensus. The district developed curriculum and lessons for the teaching of these values. A quasi-experimental research design was utilized. The treatment group was taught values as a formal part of their curriculum for a period of four …


A Comparison Of The Health Beliefs Of Florence Nightingale And Ellen G. White And The Incorporation Of Them Into Their Respective Schools Of Nursing, Ruth Duncan Abbott Jan 2001

A Comparison Of The Health Beliefs Of Florence Nightingale And Ellen G. White And The Incorporation Of Them Into Their Respective Schools Of Nursing, Ruth Duncan Abbott

Dissertations

This study explored the similarities and differences of the health beliefs of Ellen G. White and Florence Nightingale and how these beliefs were incorporated into each of their respective schools of nursing, the Nightingale Training School for Nurses at St. Thomas' Hospital and the Medical Missionary Training School for Nurses at the Battle Creek Sanitarium in Battle Creek, Michigan. The research also examined the contextual factors that shaped each woman's philosophy and influenced the manner in which they carried out their work. Additionally, the research provides information about the historical context surrounding the beginnings of modern nursing, education, health, society, …