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A Comprehensive Part Model And Graphical Schema Representation For Object-Oriented Databases, Michael H. Halper Oct 1993

A Comprehensive Part Model And Graphical Schema Representation For Object-Oriented Databases, Michael H. Halper

Dissertations

Part-whole modeling plays an important role in the development of database schemata in data-intensive application domains such as manufacturing, design, computer graphics. text document processing, and so on. Object-oriented databases (OODBs) have been targeted for use in such areas. Thus, it is essential that OODBs incorporate a part relationship as one of their modeling primitives. In this dissertation, we present a comprehensive OODB part model which expands the boundaries of OODB part-whole modeling along three fronts. First, it identifies and codifies new semantics for the OODB part relationship. Second, it provides two novel realizations for part relationships and their associated …


Morphological Operations In Image Processing And Analysis, Chamim Christopher Pu Oct 1993

Morphological Operations In Image Processing And Analysis, Chamim Christopher Pu

Dissertations

Morphological operations applied in image processing and analysis are becoming increasingly important in today's technology. Morphological operations which are based on set theory, can extract object features by suitable shape (structuring elements). Morphological filters are combinations of morphological operations that transform an image into a quantitative description of its geometrical structure which based on structuring elements. Important applications of morphological operations are shape description, shape recognition, nonlinear filtering, industrial parts inspection, and medical image processing.

In this dissertation, basic morphological operations are reviewed, algorithms and theorems are presented for solving problems in distance transformation, skeletonization, recognition, and nonlinear filtering. A …


Medium Access Control Mechanisms For High Speed Metropolitan Area Networks, Michail Papamichail Oct 1993

Medium Access Control Mechanisms For High Speed Metropolitan Area Networks, Michail Papamichail

Dissertations

In this dissertation novel Medium Access Control mechanisms for High Speed Metropolitan Area networks are proposed and their performance is investigated under the presence of single and multiple priority classes of traffic. The proposed mechanisms are based on the Distributed Queue Dual Bus network, which has been adopted by the IEEE standardization committee as the 802.6 standard for Metropolitan Area Networks, and address most of its performance limitations. First, the Rotating Slot Generator scheme is introduced which uses the looped bus architecture that has been proposed for the 802.6 network. According to this scheme the responsibility for generating slots moves …


On Generalized Adaptive Neural Filter, Zhiqiang Zhang Oct 1993

On Generalized Adaptive Neural Filter, Zhiqiang Zhang

Dissertations

Linear filters have historically been used in the past as the most useful tools for suppressing noise in signal processing. It has been shown that the optimal filter which minimizes the mean square error (MSE) between the filter output and the desired output is a linear filter provided that the noise is additive white Gaussian noise (AWGN). However, in most signal processing applications, the noise in the channel through which a signal is transmitted is not AWGN; it is not stationary, and it may have unknown characteristics.

To overcome the shortcomings of linear filters, nonlinear filters ranging from the median …


Statistical, Random And Fractal Characterizations Of Surface Topography With Engineering Applications, Gongyao Zhou Oct 1993

Statistical, Random And Fractal Characterizations Of Surface Topography With Engineering Applications, Gongyao Zhou

Dissertations

Two methods, namely the conventional and fractal geometry methods, are developed for surface topography characterization. The conventional method utilizing statistical and random process techniques is used to study waterjet machined surfaces. In the study the waterjet surfaces are separated into smooth and striation zones, where striation influence is negligible in the smooth zone. It is found that the smooth zone has a random, moderately isotropic texture, with the height distribution nearly Gaussian. In the striation zone the major frequencies of the surface profile power spectra are independent of cutting parameters, while the amplitudes of these frequencies monotonically increase with cutting …


Distances Associated With Subgraphs And Subdigraphs, Steven John Winters Jun 1993

Distances Associated With Subgraphs And Subdigraphs, Steven John Winters

Dissertations

The defining properties of several important subgraphs and subdigraphs rely on the concept of distance in graphs and digraphs. In this dissertation, we investigate many of these subgraphs and subdigraphs.

In Chapter I, we present some preliminary definitions and examples. In addition, many known results are recalled. We then introduce several new induced subgraphs and subdigraphs.

In Chapter n, we investigate the general structure of the center and periphery of a graph. We introduce two new induced subgraphs of the center along with a new induced subgraph of the periphery of a graph in order to study these structures.

For …


The Job Search Process In Michigan 1990-1991, Zhuoyan Gu Jun 1993

The Job Search Process In Michigan 1990-1991, Zhuoyan Gu

Dissertations

Two statewide general public surveys of non-retired adults conducted in March of 1990 and 1991 were analyzed to examine patterns of job search activity. Primary attention was placed on the 1991 survey. The core questions asked were about preferences for future job search media in terms of the respondents' past job seeking experiences . The general pattern observed was a movement away from the public state employment service towards "informal" contacts. There were, however, important differences in terms of the respondents' age, sex, education, occupation, and prior employment experiences.


The Effects Of Two Motivational Factors On Accuracy And Persistence For Second Graders, Jesse D. Baker Jun 1993

The Effects Of Two Motivational Factors On Accuracy And Persistence For Second Graders, Jesse D. Baker

Dissertations

Promoting and maintaining motivation in elementary students is an ongoing problem. This study hypothesized that (a) feedback has a greater motivational effect on persistence and on accuracy for second graders than does no feedback, and (b) knowledge of results feedback has a greater motivational effect than does pleasant feeling tone feedback. Evidence from the study showed mixed support for the hypotheses.

The study compared two forms of feedback and the absence of feedback. One group received praise in the form of general, positive statements—classified as feeling tone—about their work while completing mathematics computational portions of the second grade 1989 Stanford …


A Comparison Of Strategic Decision Task Variable Analysis Between School And Business Executives, Peter A. Behnke Jun 1993

A Comparison Of Strategic Decision Task Variable Analysis Between School And Business Executives, Peter A. Behnke

Dissertations

The purpose of this study was to examine the differences between school and business executives when making strategic decisions through a comparison of task variable analysis skills. The hypothesis for the study was: After reading a case study describing a strategic decision- making situation, business executives will have more correct responses than school executives on an author written evaluation instrument. The evaluation instrument was designed to measure the subjects' analysis skills of 10 different decision-making task variables.

Thirty Wisconsin school district superintendents and 30 business executives were randomly selected to participate in the study. The results indicated that the difference …


The Identification And Validation Of Sociopsycholinguistic Strategies For Integrating Reading And Writing At The Postsecondary Level, Gail L. Landberg Jun 1993

The Identification And Validation Of Sociopsycholinguistic Strategies For Integrating Reading And Writing At The Postsecondary Level, Gail L. Landberg

Dissertations

The purpose of this study was to identify a common set of strategies as determined by two panels of experts (practitioners and theorists), which reflected a sociopsycholinguistic teaching model integrating reading and writing processes on the postsecondary level.

At the present time approximately 30% of the students entering college have some type of skill need, and tertiary institutions have been compelled to admit this type of developmental student to survive financially. Higher education has responded to this crisis by providing developmental programs to assist students in improving their basic skills.

Despite the fact that recent educational research on language acquisition …


Constitutive Equation For Concrete Using Strain-Space Plasticity Model, Yuxiang Xing May 1993

Constitutive Equation For Concrete Using Strain-Space Plasticity Model, Yuxiang Xing

Dissertations

Plasticity theory has been used to model the concrete constitutive relationship for about two decades. With the modifications and refinement based on experimental data, achievement has been made in these plasticity models for concrete. Almost all the existing models are developed in stress space. With a lot of experimental data and more understanding about stress states of concrete, the stress-space model shows many advantages. Because of this and also due to conventional engineering practice, the stress-space plasticity approach has been in the dominant position. However, the conventional stress-space plasticity method has one inherent drawback in which it cannot deal with …


On Orthogonal Collocation Solutions Of Partial Differential Equations, Herli Surjanhata May 1993

On Orthogonal Collocation Solutions Of Partial Differential Equations, Herli Surjanhata

Dissertations

In contrast to the h-version most frequently used, a p-version of the Orthogonal Collocation Method as applied to differential equations in two-dimensional domains is examined. For superior accuracy and convergence, the collocation points are chosen to be the zeros of a Legendre polynomial plus the two endpoints. Hence the method is called the Legendre Collocation Method. The approximate solution in an element is written as a Lagrange interpolation polynomial. This form of the approximate solution makes it possible to fully automate the method on a personal computer using conventional memory.

The Legendre Collocation Method provides a formula for …


Minimum Redundancy Array Structure For Interference Cancellation, Wan-Ling Chen May 1993

Minimum Redundancy Array Structure For Interference Cancellation, Wan-Ling Chen

Dissertations

Adaptive antenna arrays are widely used in many advanced radar, sonar, and communication systems because of their effectiveness in cancelling intentional or unintentional interferers. A uniformly spaced linear array, referred to as a Uniform Regular Array (URA), is the usual structure used for interference cancellation. The Minimum Redundancy Array (MRA) structure proposed in this work is a special kind of thinned array whose application was limited in the past to direction finding. MRAs with the same number of array elements can resolve directions of much more closely spaced signals than URAs.

The URA structure is customarily utilized for interference cancellation, …


Algorithms For Generation Of Path-Methods In Object-Oriented Databases, Ashish Mehta May 1993

Algorithms For Generation Of Path-Methods In Object-Oriented Databases, Ashish Mehta

Dissertations

A path-method is a mechanism in object-oriented databases (OODBs) to retrieve or to update information relevant to one class that is not stored with that class but with some other class. A path-method is a method which traverses from one class through a chain of connections between classes to access information at another class. However, it is a difficult task for a user to write path-methods, because it might require comprehensive knowledge of many classes of the conceptual schema, while a typical user has often incomplete or even inconsistent knowledge of the schema.

This dissertation proposes an approach to the …


Dmodel And Dalgebra : A Data Model And Algebra For Office Documents, Fortune Solani Mhlanga May 1993

Dmodel And Dalgebra : A Data Model And Algebra For Office Documents, Fortune Solani Mhlanga

Dissertations

This dissertation presents a data model (called D_model) and an algebra (called D_ algebra) for office documents. The data model adopts a very natural view of modeling office documents. Documents are grouped into classes; each class is characterized by a "frame template", which describes the properties (or attributes) for the class of documents. A frame template is instantiated by providing it with values to form a "frame instance" which becomes the synopsis of the document of the class associated with the frame template. Different frame instances can be grouped into a folder. Therefore, a folder is a set of frame …


Characterization Of Advanced Etching Reactors Using Novel Diagnostic Tools, Vipulkumar Patel May 1993

Characterization Of Advanced Etching Reactors Using Novel Diagnostic Tools, Vipulkumar Patel

Dissertations

Plasma etching equipment used for sub-micron integrated circuit fabrication at present are exclusively based on 13.56 MHz, capacitively coupled, parallel-plate geometry. The underlying mechanisms of plasma processes in these reactors are not well understood and there is even less understanding of how the etch-tool parameters relate to the plasma discharge characteristics which actually determine the etch process. In this thesis, new diagnostic techniques were applied for the characterization and optimization of plasma etching processes in various reactor configurations.

Specifically, diode and triode configurations were studied extensively using tuned scanning Langmuir probes. Both radial and axial distributions of plasma density were …


Unreinforced Masonry Structures : Nonlinear Analysis And Evaluation Of Some Rehab Schemes, Sanjay Mehta May 1993

Unreinforced Masonry Structures : Nonlinear Analysis And Evaluation Of Some Rehab Schemes, Sanjay Mehta

Dissertations

Unreinforced masonry (URM) structures have been a common type of construction in the past and are still used in regions of low seismicity. Retrofitting of these structures is necessary because of two reasons: Firstly, observed damage after earthquakes reveals that URM construction is one of the most hazardous constructions even in the region of low seismicity; secondly, reclassification of seismic zones would require retrofitting of existing structures to comply with new guidelines for earthquake design.

Retrofitting measures require that the response of original and new structural systems as well as their interaction be considered. It is therefore important to correctly …


Megsdf Mega-System Development Framework, Tamar Zemel May 1993

Megsdf Mega-System Development Framework, Tamar Zemel

Dissertations

A framework for developing large, complex software systems, called Mega-Systems, is specified. The framework incorporates engineering, managerial, and technological aspects of development, concentrating on an engineering process. MegSDF proposes developing Mega-Systems as open distributed systems, pre-planned to be integrated with other systems, and designed for change.

At the management level, MegSDF divides the development of a Mega-System into multiple coordinated projects, distinguishing between a meta-management for the whole development effort, responsible for long-term, global objectives, and local managements for the smaller projects, responsible for local, temporary objectives.

At the engineering level, MegSDF defines a process model which specifies the tasks …


Competition Between Two Microbial Populations In A Sequencing Fed-Batch Reactor And Its Implications For Waste Treatment Applications, Sitaram Dikshitulu May 1993

Competition Between Two Microbial Populations In A Sequencing Fed-Batch Reactor And Its Implications For Waste Treatment Applications, Sitaram Dikshitulu

Dissertations

Pure and simple competition between two microbial populations in a sequencing fed-batch reactor (SFBR) was studied both at the theoretical and experimental level. Competition occurred for a single chemical pollutant which could serve as the sole carbon and energy source for both competitors. A mathematical model describing the process under inhibitory kinetics (as is usually the case with hazardous and toxic substances) was derived and theoretically analyzed. The model predicts that the dynamics of a SFBR, and the kinetics of biodegradation, result in a complex set of operating regimes in which neither species, only one species, or both species survive …


Robust Rank-Based Inference Procedures In The Heteroscedastic Linear Model, Sherry L. Dixon Apr 1993

Robust Rank-Based Inference Procedures In The Heteroscedastic Linear Model, Sherry L. Dixon

Dissertations

No abstract provided.


The Impact Of Test Sophistication On Tenth Grade Students’ Michigan Educational Assessment Program (Meap) Scores, Iris Williams Apr 1993

The Impact Of Test Sophistication On Tenth Grade Students’ Michigan Educational Assessment Program (Meap) Scores, Iris Williams

Dissertations

The primary purpose of this study was to determine whether test sophistication training would result in more tenth grade students achieving performance levels on the Michigan Educational Assessment Program (MEAP) subtests in mathematics and reading which would entitle them to receive the state endorsed diploma.

Two groups of English II students (grade 10) from the same school participated in the study. One group received test sophistication instruction, and the other received no treatment. During the test sophistication training, students were instructed using the Ace That Test Preparation for Success Student Guide (Yarosz & Yarosz, 1991a) which was based on the …


Analysis Of The Optimum Extraction System Design For The Separation And Purification Of Rare Earths, Kenneth Yeon-Kang Chan Jan 1993

Analysis Of The Optimum Extraction System Design For The Separation And Purification Of Rare Earths, Kenneth Yeon-Kang Chan

Dissertations

A mathematical model for the liquid-liquid equilibrium of the lanthanide and yttrium oxides in the nitric acid - water - tributyl phosphate (HNO3-H2O-TBP) two-phase system has been developed. This model is based on the interrelationships of chemical reactions, phase equilibrium, and material balance. The chemical reactions were modelled using experimentally derived empirical equations for components involved. The distribution coefficients of 16 rare earths which were experimentally determined. by UK Harwell Laboratory were used to evaluate the parameters of this equilibrium model. Once model parameters are determined, material balance for all species in the HNO3-H …


Analysis Of A Band-Saw, Suat Ali Ozsoylu Jan 1993

Analysis Of A Band-Saw, Suat Ali Ozsoylu

Dissertations

The solution for the transverse oscillations of a band-saw is determined. Two different models are treated: a fourth-order model and a second-order model. The response characteristics for both models are determined using Laplace transformation. To obtain the inverse Laplace Transform for the fourth-order model, it was necessary to fmd the frequencies by applying the Extended Lanczos Method in order to overcome the problem for computer overflow.

The limits of stability for both models are studied by plotting the eigenvalues against changing parameter values. Conditions for the onset of divergence and flutter instabilities, which need to be taken into account in …


Study Of Surface Properties Produced By Magneto-Plasma On Nitriding For Improving Wear Resistance, I-Tsung Shih Jan 1993

Study Of Surface Properties Produced By Magneto-Plasma On Nitriding For Improving Wear Resistance, I-Tsung Shih

Dissertations

In this work a newly developed surface treatment process, Magneto-Plasma Ion Nitriding process, was developed and studied. This process was developed to increase durability and wear resistance of operational surfaces of different machine components.

In this study, orthogonal experimental analysis was used to develop, optimize, and select the process parameters. Coating layers were characterized and studied by using scanning electron microscopy(SEM), Auger electron spectroscopy(AES), and image analysis system. The influence of different process treatment parameters, such as temperature, nitrogen concentration, and magnetization, on the layers properties was studied. The mechanism of layer formation and bonding was proposed and a mathematical …


Investigation Of The Consumer Electronics Bus, Jaesoo Yang Jan 1993

Investigation Of The Consumer Electronics Bus, Jaesoo Yang

Dissertations

The objectives of this dissertation are to investigate the performance of the Consumer Electronics Bus (CEBus) and to develop a theoretical formulation of the Carrier Sense Multiple Access with Contention Detection and Contention Resolution (CSMA/CDCR) with three priority classes protocol utilized by the CEBus

A new priority channel assigned multiple access with embedded priority resolution (PAMA/PR) theoretical model is formulated. It incorporates the main features of the CEBus with three priority classes. The analytical results for throughput and delay obtained by this formulation were compared to simulation experiments. A close agreement has been found thus validated both theory and simulation …


On Adaptive Censored Cfar Detection, Loizos Anastasiou Prastitis Jan 1993

On Adaptive Censored Cfar Detection, Loizos Anastasiou Prastitis

Dissertations

In an automatic radar detection system the received signal in every range resolution cell is compared with a threshold to test for the presence of a target. A Neyman-Pearson type test is used which maximizes the probability of detection for a fixed probability of false alarm. For the simple case where the noise is homogeneous a fixed threshold is chosen to achieve the designed constant false alarm rate (CFAR). In the more realistic case the noise background is non-stationary due to clutter and interference. In this situation, the threshold used for testing a particular cell is usually set adaptively using …


An Evaluation Study Of The Effects Of The Pirk Reading Program On Reading And Learning Development In Learning-Disabled Students, Ethelyn Elliott Shippey Edd Jan 1993

An Evaluation Study Of The Effects Of The Pirk Reading Program On Reading And Learning Development In Learning-Disabled Students, Ethelyn Elliott Shippey Edd

Dissertations

An emerging view on learning disabilities is that failure in learning to read in the early grades results in continuing failure in school, along with cognitive and social/emotional dysfunctions: Educational leaders have called for reading programs that are maximally effective and minimally time-consuming, and are suited to the needs of our particular students. Leaders in the field of special education stressed a need for the prevention of failure. This evaluation study examined how the PIRK reading program components fit with the current literature on teaching reading and language arts to all children and to LD children. This study investigated the …


A Continuous Culture Model To Examine Factors That Affect Transduction Among Pseudomonas Aeruginosa, Jean Replicon Jan 1993

A Continuous Culture Model To Examine Factors That Affect Transduction Among Pseudomonas Aeruginosa, Jean Replicon

Dissertations

No abstract provided.


An Analysis Of Elementary School Districts With Merit Pay Programs For Their Principals, Winston Johnson Jan 1993

An Analysis Of Elementary School Districts With Merit Pay Programs For Their Principals, Winston Johnson

Dissertations

No abstract provided.


The Evolving Role Of Research In Mexican Graduate Programs In The Field Of Education: A Case Study Of Six Selected Programs (1980-1992), Romay Maria De La Luz Munoz Jan 1993

The Evolving Role Of Research In Mexican Graduate Programs In The Field Of Education: A Case Study Of Six Selected Programs (1980-1992), Romay Maria De La Luz Munoz

Dissertations

No abstract provided.