Digital Commons Network^™

Invariant Operator Ranges Of Operator Algebras, D Benjamin Mathes

Doctoral Dissertations

Given a norm closed unital algebra ${\cal A}$ of operators on Hilbert space, a sublattice of Lat$\sb{1/2}{\cal A}$ is identified, which we denote Lat$\sb{\rm cb}{\cal A}$. It is proved that Lat$\sb{\rm cb}{\cal A}$ is lattice isomorphic to Lat$\sb{1/2}{\cal A}\otimes{\cal K}$ (where ${\cal K}$ denotes the ideal of compact operators on an infinite dimensional separable Hilbert space). This isomorphism is used to prove theorems describing Lat$\sb{\rm cb}{\cal A}$ by carrying over know results concerning Lat$\sb{1/2}{\cal A}\otimes{\cal K}$. It is then shown that Lat$\sb{\rm cb}{\cal A}$ can always be written as the set of ranges of operators that intertwine the algebra with …

Twist-Bending Vibrations Of Horizontally Circular Curved Beams Considering Effects Of Transverse Shear, Rotatory Inertia And Warping, Bor-Tsung Hsiao

Doctoral Dissertations

This thesis is devoted to the dynamic analysis of horizontally circular curved beams. The direct stiffness method is used to derive the dynamic stiffness matrix for finding the natural frequencies and joint moments of curved beams having different rectangular cross-sections. Four examples are presented to illustrate the application of the proposed method and to show the effects of rotatory inertias, shear deformation, warping and opening angle of the arc on the beam. First three examples are for the free vibration of the beam. In these examples, beams with different thickness are used for finding effects of warping. In each example, …

An Integrated Programming Environment For Pseudo-Code Development, Ipe-Pc, Nurcan Coskun

Doctoral Dissertations

"An Integrated Programming Environment, IPE-PC, that supports pseudo-code development has been designed and implemented. This environment is based on a Pascal-like language which is designed according to the requirements of a language-based environment. The nucleus of IPE-PC is a language-based editor which represents programs as graphs internally. The same representation is used in every mode of the environment (i.e., editing, compilation, execution, debugging and translation). The system provides facilities to take advantage of both top-down and bottom-up programming. Stepwise refinement has been supported by providing comment structures that can be transformed into procedures. Bottom-up programming is supported because it is …

The Role Of Term Symmetry In E-Unification And E-Completion, Blayne E. Mayfield

Doctoral Dissertations

“A major portion of the work and time involved in completing an incomplete set of reductions using an E-completion procedure such as the one described by Knuth and Bendix [KB70] or its extension to associative-commutative equational theories as described by Peterson and Stickel [PS81] is spent calculating critical pairs and subsequently testing them for coherence. A pruning technique which removes from consideration those critical pairs that represent redundant or superfluous information, either before, during, or after their calculation, can therefore make a marked difference in the run time and efficiency of an E-completion procedure to which it is applied.

The …

Complete Sets Of Reductions Modulo A Class Of Equational Theories Which Generate Infinite Congruence Classes, Timothy B. Baird

Doctoral Dissertations

"In this paper we present a generalization of the Knuth-Bendix procedure for generating a complete set of reductions modulo an equational theory. Previous such completion procedures have been restricted to equational theories which generate finite congruence classes. The distinguishing feature of this work is that we are able to generate complete sets of reductions for some equational theories which generate infinite congruence classes. In particular, we are able to handle the class of equational theories which contain the associative, commutative, and identity laws for one or more operators.

We first generalize the notion of rewriting modulo an equational theory to …

Toward The Development Of A Knowledge-Based Construction Schedule Planning System, Nordin Bin Yunus

Doctoral Dissertations

"This research attempts to model and prototype a knowledge-based system for use in the construction industry to accomplish the automatic generation of initial construction schedules. The schedule can be transformed into a logical network that provides a physical representation of the construction operations plan. The prototype system, which requires symbolic processing and reasoning, is developed based on an intensive modeling that rationally examines industry practice.

The model identifies work breakdown and precedence relationship as the two major concepts in schedule planning. Work breakdown is concerned with the identification of construction activities that result in the completion of project elements. Precedence …

Symbolic Automation And Numerical Synthesis For Robot Kinematics, Jen Sriwattanathamma

Doctoral Dissertations

"This research analyzes three topics in robot arm kinematics. First, the direct kinematics which determines the Cartesian position and orientation of the end effector for the specified values of joint parameters is analyzed. Second, the differential motions concerning the differential relationships between the command variables in position and orientation of the end effector and the joint-controlled variables are studied. Finally, the inverse kinematics which determines the joint variables for a specified Cartesian position and orientation of the end effector is considered.

This dissertation presents a methodology for incorporating the artificial intelligence types of knowledge into automating solutions for the direct …

Resource Use Rates: Estimation Of Time Invariant Decision Rules (Erosion), Douglas John Lawrence

Doctoral Dissertations

As interest in soil conservation has increased, understanding the soil management decision rule used by farmers has become more important. The model developed to analyze the optimal decision rule for soil use rates is essentially a supply response model which assumes rational expectations. It can be characterized as a dynamic optimal control model with feedback from decisions to states. Three Stage Least Squares estimation is re-interpreted to fit the requirements of rational expectations. The estimated coefficients suggest that soil conservation policy must consider general economic variables as well as traditional variables such as soil depth and cost sharing to be …

Town And Province In Revolutionary New Hampshire: A Stable Political Culture Confronts Change, 1765--1776, Marilyn Mulzer Robbert

Doctoral Dissertations

The study analyzes the relationship of the towns to the provincial government between 1765 and 1776 to understand the underlying process of the coming of the Revolution in New Hampshire. The focus is on the towns, and the main sources are unpublished town records.

For one part of the study, I developed a system to identify legislative leaders (a modification of Jack Greene's method), used Gini scores to compare the General Assemblies with the Provincial Congresses and the 1776 House of Representatives, and constructed a composite biography for the 296 men who served during the period.

A comparison of the …

The Ronson Ship: The Study Of An Eighteenth-Century Merchantman Excavated In Manhattan, New York In 1982, Warren Curtis Riess

Doctoral Dissertations

During a pre-construction archaeological investigation at 175 Water Street, Manhattan, New York in 1982, excavators discovered an eighteenth-century merchant ship. The port side of the ship was excavated and recorded and the bow was taken apart and saved. Since that time historical and archaeological studies have been conducted to interpret the site to glean information about eighteenth-century technology and economics. The remains of this ship are particularly important because no draft or other remains of early eighteenth-century transatlantic merchantmen have been discovered.

The ship appears to be a Virginia-built ship which sailed between the Chesapeake and England or Scotland carrying …

Simplified Analysis Of A Cladding-Frame Structural System, Nancy Marie Alberto

Doctoral Dissertations

This dissertation presents a simplified approach for the preliminary design and static analysis of a cladding-frame structural system subjected to concentrated, lateral loading conditions. The simplified approach, which utilizes the finite element analysis method, reduces the number of computations required for analysis of a structurally cladded frame to that of an architecturally cladded frame. This research develops a modified beam element to analytically replace a cladding panel element while retaining its structural benefits. The modified beam element is derived using a 16 degree of freedom isoparametric element and displacement correlations determined from the studies of a two-story, single bay frame …

Parasites Of The Yellowtail Flounder (Limanda Ferruginea, Storer, 1839) From The Western North Atlantic, Salvatore Anthony Testaverde

Doctoral Dissertations

A study was conducted of parasites from the yellowtail flounder, Limanda ferruginea (Storer, 1839) taken from the western North Atlantic, United States. Monthly studies, from the Cape Ann, Massachusetts area, April 1977 to 1979, were initiated to determine prevalence, mean intensity, and range of parasites in relation to host and environmental factors. A second study was conducted to determine parasite-mix between the Cape Cod and the Georges Bank subareas, including preliminary findings from the southern New England and the Middle Atlantic subareas. From 40 previously reported parasites, including adults, metacercariae, plerocercoids, and juvenile forms, a total of 15 species of …

Intensional Reasoning About Knowledge, Oliver B. Popov

Doctoral Dissertations

"As demands and ambitions increase in Artificial Intelligence, the need for formal systems that facilitate a study and a simulation of a machine cognition has become an inevitability. This paper explores and developes the foundations of a formal system for propositional reasoning about knowledge. The semantics of every meaningful expression in the system is fully determined by its intension, the set of complexes in which the expression is confirmed. The knowledge system is based on three zeroth-order theories of epistemic reasoning for consciousness, knowledge and entailed knowledge. The results presented in the paper determine the soundness and the completeness of …

Development Of Design Criteria For Ferritic Stainless Steel Cold-Formed Structural Members And Connections, Pieter Van Der Merwe

Doctoral Dissertations

"This dissertation describes the development of the basic criteria needed for the design of structural members cold-formed from certain ferritic stainless steels. The Allowable Stress Design method as well as the Load and Resistance Factor Design method receive attention. The ferritic stainless steels under consideration are: Types AISI 409 and 430 as well as a modified Type 409 steel, designated 3CR12 steel, developed and produced by the speciality steel producing company, Middelburg Steel and Alloys in South Africa.

The mechanical properties needed for structural design are established. It is shown through an experimental study that the design provisions for the …

Effects Of The Luminous Environment On Managerial Decision Making, Marc Clay Belcher

Doctoral Dissertations

"Little is known about the influence the physical environment may have on the way a manager goes about making decisions. This work considers one element of the environment, lighting, and attempts to establish a relationship between that element and the decision strategy a manager may select.

From a review of the literature on the effects of light on man and from the field of decision making, a model is posited suggesting that the luminous environment affects decision making. Since others have established that mood influences how decisions are made, and since it is suggested in the literature that lighting affects …

Microemulsions, Lyotropic Liquid Crystals, And Other Association Structures, Jiafu Fang

Doctoral Dissertations

"Phase diagrams have been determined showing the extent of the inverse micellar or microemulsion region for several ionic surfactants and some cosurfactants. Hexylamine has been found to be a very effective cosurfactant giving rise to very good water solubilizing capacity at extremely low surfactant concentrations and very low cosurfactant levels at rather high initial hydrocarbon levels.

A fairly extensive study of phase equilibria of the system composed of sodium dodecyl sulfate, hexylamine, heptane, and water has been carried out. The conductivity behavior of the inverse micellar or microemulsion phase of the system shows the percolation phenomenon. Low angle X-ray diffraction …

Phase Equilibria From Pvt Measurements For Carbon Dioxide, Water And N-Decane, Michael Nduka Okafor

Doctoral Dissertations

"Phase equilibrium properties for the carbon dioxide - water - n-decane system were determined from pressure-temperature-volume (PVT) measurements. PVT properties were also obtained for pure carbon dioxide and water, and the binary mixtures of carbon dioxide - water and carbon dioxide - n-decane. The experiments were conducted at temperatures of 313.17, 353.15 and 393.15 Kelvin, and at pressures from 37 to 416 bar. Measurements for the mixtures were terminated when complete miscibility was observed.

The Perturbed-Hard-Chain (PHC) equation of state developed by Gmehling et al. (1979) was chosen to correlate the measured data because of its ability to handle the …

Amphiphile Association Structures, Yun Yang

Doctoral Dissertations

"The amphiphile association behavior of Aerosol OT (sodium di-w-ethylhexylsulfoccinate) and p-xylene in combination with mixtures of different ratios of glycerol/water systems was studied and compared to that in the corresponding water and glycerol systems. The presence of glycerol strongly destabilized the inverse hexagonal liquid crystal phase observed in the aqueous system. The glycerol showed more ability to penetrate into the amphiphile bilayer than water in the lamellar liquid crystal phase. The influences of water and glycerol on the organization of amphiphile in the lamellar liquid crystal phase are of the same order.

The gross diffusion coefficient of 1% 2,4-diamino-6-piperidinopyrimidine-3-oxide in …

Operator Ranges Of Shifts And C*-Algebras (Strange Range, Quasi-Similarity, Lattice), Charles Lucien Roy

Doctoral Dissertations

It is shown that Lat(, 1/2)(H('(INFIN))(S)), the invariant operator ranges of the commutant of the unilateral shift, is a proper sub-lattice of the lattice of invariant operator ranges of the unilateral shift, S. The notion of a strange operator range for S of order n where n (ELEM) is introduced and it is demonstrated that there exist strange ranges for S of every order. This is done by deriving an operator range condition which is sufficient to insure that a pair of quasi-similar compressions of shifts really be similar. A set of operator ranges which forms a sub-lattice of Lat(, …

Estimation Of The Fisher Effect On The Term Structure Of Interest Rates Employing A Term Structure Of Inflationary Expectations, Phyllis Wells Isley

Doctoral Dissertations

This study deals with the estimation of the effect of a term structure of inflationary expectations on the term structure of interest rates. By estimating the Fisher effect over the entire term structure, this analysis captures the associational effects between values of the interest rates along a term structure and values of inflationary expectations along a term structure.

The study contains a discussion of the Fisher hypothesis as it was developed and tested by Irving Fisher. Models of inflationary expectations and previous applications of these to test the Fisher effect are discussed.

A method of constructing a term structure of …

Technical Change And Profitability: The Long-Period Behavior Of The Rate Of Profit (Competition, Rationality), Benigno Valdes

Doctoral Dissertations

This dissertation provides a theoretical inquiry into the effects of technical change on profitability. In the center of the discussion lies the Marxian 'Law of the Falling Tendency of the Rate of Profit' (LFTRP). The LFTRP maintains that mechanization, i.e. the introduction of cost-reducing techniques of the capital-using-labor-saving type, results in a lower average rate of profit. This proposition is denied by the Okishio theorem, which says that the introduction of such techniques is incompatible with a falling rate of profit.

In order to evaluate Okishio's claim, a model of the economy which incorporates fixed capital is constructed, and on …

Interaction Of Polycyclic Aromatic Hydrocarbons With Dissolved And Sediment Associated Humic Materials (Nmr, Fluorescence), Thomas Donald Gauthier

Doctoral Dissertations

A fluorescence quenching method was developed for determining association constants of polycyclic aromatic hydrocarbons (PAH)s with dissolved and sediment bound humic materials. The technique is based upon the observation that PAH fluorescence in aqueous solution is quenched upon association with humic material. Association constants are derived from the fractional decrease in fluorescence intensity as a function of added humic material using Stern-Volmer plots. No separation is required and since the technique involves a ratio measurement the exact concentration of pollutant is not required. Anthracene-humic acid association constants normalized to the fraction of organic carbon in the sorbent (K(,oc)), determined by …

Analysis And Simulation Of The Pneumatic Braking System Of Freight Trains, Khaled Sayed Abdol-Hamid

Doctoral Dissertations

In North America, and in many other parts of the world, freight trains still employ pneumatic equipment for braking. The 26C locomotive valve and control valves of the cars are connected by a brake pipe which serves the dual purpose of conducting pneumatic power and transmitting the control signal (brake signal) from the locomotive to each car of the train. The development of the air brake system has been largely empirical and experimental, which may take years to develop a new design.

In this thesis, a new brake pipe mathematical model is developed, including the interaction of the branch pipe. …

The Role Of Error Analysis, Diagnostic Grading Procedures, And Student Reflection In First Semester Calculus Learning (Epistemology, Metacognition, Inquiry), Karen Jean Geuther

Doctoral Dissertations

The present study is an integrative study designed to explore the nature of student difficulties within the context of a first semester college calculus course. The techniques of error analysis were used to identify and categorize the student difficulties. Insights gained from this categorization served as the basis for the design and development of calculus grader preparation materials implemented with a subgroup of undergraduate calculus graders. These grader preparation materials emphasized grader diagnosis of student difficulties and student reflection on errors and process. Current preparation procedures served as the control on the basis of which comparisons and evaluations were made. …

Fire Resistance Of Concrete-Filled And Reinforced Concrete Columns, Mohamed El-Shayeb

Doctoral Dissertations

In order to calculate the fire resistance of a building component, it is necessary to know the temperature history of the component during exposure to fire. In this dissertation a numerical method is described for calculating the temperature field in fire-exposed columns. The procedure is based on a finite difference method for calculating the temperature history of concrete-filled square steel and cylindrical reinforced concrete columns. Two mathematical models and their related computer programs for these columns are presented in this dissertation.

Furthermore, the Division of Building Research of the National Research Council of Canada, is now carrying out extensive experimental …

A Study Of Electron-Ion And Ion-Ion Recombination In Atmospheric Gas Discharges, Michael Corbin Cornell

Doctoral Dissertations

"In separate experiments, the electron-ion recombination rate, Y_ei, has been measured in CO₂ and in mixtures of He, CO₂, and N₂; and the ion-ion recombination rate, Y_ii, has been measured in SF6 and in mixtures of SF₆ and CH₄. The rate constant was determined by analyzing the rising edge of the discharge current pulse. Measurements were made as functions of reduced electric field strength, gas pressure, and gas composition.

In the electron-ion recombination study, Y_ei in CO₂ and in mixtures containing N₂ and CO_{2 …}

An Investigation Of Signs For Median Crossovers, Gillian M. Worsey

Doctoral Dissertations

“This paper describes a study of advance warning signs for median crossovers on divided highways. Candidate crossover signs were identified from a literature review, survey of current State practices and discussions with FHWA personnel. Seven of these signs were selected for further testing in a laboratory study for legibility, understanding and driver preference. Sixty subjects representing a cross-section of drivers took part in the study, thirty at the Turner-Fairbanks Highway Research Center in McLean, Virginia and thirty at the University of Missouri--Rolla in Rolla, Missouri.

Two of the seven signs were word messages and five were symbolic signs. The results …

Oxidation Kinetics Of Polycrystalline Srtio₃ And Lacro₃, Chi-Kung Jerry Yu

Doctoral Dissertations

"The oxidation kinetics of polycrystalline SrTiO₃ and LaCrO₃ were determined by measuring the time and temperature dependence of the weight and conductivity change of reduced samples. A region of fast diffusion followed by a reduced diffusion tail was observed in the TGA measurements. This observation can be interpreted as the initial diffusion along the boundaries and then spreading out into the lattice. The absence of the tail in the conductivity measurements is due to the high electron and hole mobility at the boundaries. The electrical conductivity and TGA results on Nb-doped LaCrO₃ show that at low oxygen …

Amphiphilic Association Structures And Some Aspects Of Foam Stability, Jia-Hwa Fang

Doctoral Dissertations

"This investigation was performed in order to study two interesting and important problems in foams.

Foam separation was studied in the model system of water - sodium octylsulfonate - decanol. The efficiency of foam separation as a function of surfactant concentration and decanol content were measured. The results were related to the association structures of amphiphiles in aqueous systems.

Foam polymerization was conducted in the amphiphilic system containing water, polymerizable surfactant and oleyl alcohol. Liquid foams were produced in one three - phase region. The location and optical pattern of liquid crystals on the foam surface were observed by photomicroscope …

A Semantic Basis For Parallel Algorithm Design, Roger E. Eggen

Doctoral Dissertations

"As computing demands increase, emphasis is being placed on parallel architectures- To efficiently use parallel machines, software must be designed to take advantage of these machines. This research concentrates on an abstraction of algorithm design to permit the expression of parallel programs. The abstraction emphasizes thought about algorithms at a high level as opposed to algorithm implementation at a statement level. A model based on data flow allows algorithm expression using flow diagrams. The model specifies operating system requirements that support parallel programming at a module level. Paths are used to carry data between modules. Data enter modules through ports. …