Digital Commons Network^™

The Dielectric Slab-Wedge Antenna, B. Keith Christensen

Theses

A theoretical model and numerical investigation of the directive gain of a dielectric slab-wedge radiator is presented. The model is based on a union of the classical dielectric slab equations, local mode theory, and equivalent current distribution treatments of the truncated dielectric slab and wedge geometries.

The far field is developed from the sum of two current distributions. The slab region, up to the transition plane between slab and wedge, is replaced by equivalent electric and magnetic surface current densities. The wedge contribution is developed from a volume polarization current distribution.

Conservation of power is used to approximate the field …

Human Resources Planning In Construction Through Operations Research, Maria Pyla-Christodoulou

Theses

The purpose of this thesis is to examine different methods in the allocation of human resources in construction, using decision making through Operations Research. The methods described are divided into methods using mathematical models, and methods using heuristics. The mathematical models yield the optimum solution, while heuristics result in a satisfactory solution which can be improved by applying the optimization procedures described herein.

The human factor in construction is also examined, and methods of improving motivation among the construction workers are discussed.

Preparation And Testing Of Novel Blocked Isocyanate Dental Adhesives Based Upon Hydroxyhexylmethacrylate, Gururajan Rao

Theses

In this study dental adhesives synthesised from TDI/HHMA/pentaerythritol, with either of the blocking agents namely eugenol, o-methoxyphenol, p-cresol or o-chlorophenol were tested. Bond strengths in dentin as influenced by spacer molecules were tested. Comparison studies to determine this were performed using the same blocking agents and TDI/HEMA/pentaerythritol. The effects of i. post-extraction time and ii. dentin depth on bond-strengths were tested using two monomers: o-methoxyphenol/ TDI/HEMA/pentaerythritol and p-cresol/TDI/HEMA/pentaerythritol 1. From teeth recently extracted (2h) vs dentin aged from one to six months 2. From dentin cut from three different levels within the tooth.

The prepared dentin-adhesive samples were stored in …

Design And Optimization Of Nmos Sense Amplifiers For Vlsi Drams, Nimish K. Shah

Theses

The aim of this thesis is to study and optimize the performance of NMOS sense amplifiers used in modern VLSI DRAMs.

Initially dynamic memory cells and popular sense amplifier circuits are surveyed.

A standard five transistor sense amplifier is later chosen for detailed analysis. Layout of the circuit is drawn to get the physical parameters. Using SPICE simulator, various effects of circuit parameters are studied. From these results optimal values of these parameters are arrived at.

Also an effort is made to derive theoretically equations for the latching time of a post amplifier which is the most important part in …

Human Factors In The Design Of Computer Application Software, Curtis Springstead

Theses

The use of computers in business has expanded tremendously over the past two decades. This expansion has been possible due to increasing economies within the computer industry, and in spite of the lack of consideration shown for the users of such data processing systems. The popularity of computers has compelled users to expand their list of requirements from a computer system so that it includes ease of use.

This thesis attempts to bring together many widely dispersed studies and principles that can affect the ease of use of interactive computer systems. The material has been organized according to five components …

The Decline Of Unionism With A Legal Analysis Of The Individual Rights Of Union Members, Maria-Isabel Cubides De Gast

Theses

The American labor movement has been losing power and membership for the last few years. Historical development and several facts have affected American unionism in such a manner that nowadays less than 20% of the labor force belongs to unions.

Among the most important causes of such decline discussed herein, are the following: lack of social role of unions, failure to satisfy new workers' needs, political reality under this Administration, high unemployment rate, and lack of union democracy.

Lack of union democracy is believed to be the most damaging factor for unionism's decline. Therefore it is studied in more detail, …

The Stress Distribution Of The Frp Pressure Vessel By Using Ansys Program, Lung-John Tsai

Theses

The objective of this paper is to take advantage of a general purpose finite element computer program, called ANSYS, to analyze the surface stress distribution of a fiber reinforced plastic (FRP) laminated composite pressure vessel. The vessel is subjected to internal pressure, which is assumed to be constant over the interior surfaces.

In this paper, the material is assumed to be orthotropic, and the stress-strain relationship linear.

A FRP pressure vessel subjected to an Internal pressure, 6.895 MPa (1000 psi), is taken as an example. The results show that this approach compares well with a theoretical solution.

Ray And Beam Representation Of The Glancing Phenomena, Michael Sotiriou Vogas

Theses

Asymptotic ray theory (ART) is a widely used method dealing with problems of wave propagation in an inhomogeneous medium. The main deficiency of ART is in transition regions where rays near caustics, glancing and critical incidence fail to represent the actual wave field. Ray bundles in such transition regions have been successfully replaced with modal bundles and remainders El] in well defined profiles. However , in practical problems it is difficult to implement modal representations and almost impossible to express remainders. Recently emerging Gaussian beam method (GBM) has shown promising results in representing the total field produced by a source …

Chebyshev Approximate Solution For Stiff Problems, Kwo-En Hoh

Theses

Chebyshev polynomial and collocation methods are adapted to solve general ordinary differential equations ( initial-value problems and boundary-value problems ). Approximate solutions of initial-value problems are obtained in step-by-step fasion. the solutions have minimax absolute error in the interval and correct values at the end points. The approximate solutions of boundary-value problem will be continuous on the whole domain and have piecewise Chebyshev approximation characteristics in each subinterval of the chosen partition.

Sensitivity Analysis Of Linear Goal Programming On Priority Level Reordering, Fu-Chia Hor

Theses

The purpose of this research is to study on the sensitivity analysis of priority level reordering of a goal programming model. Two approaches are presented in this study to handle this priority level reordering analysis. The first one is an algorithm to generate the solution of a similar problem with different priority level ordering of the original one utilizing the final solution tableau of the original problem. In doing so, calculation steps and time are saved tremendously.

The second approach is based on the fact that some goal programming problem of different priority level ordering has the same solution as …

Study Of The Effects Of Pumping Pressure On The Properties Of Fresh Concrete, Dinesh Vithal Kenkre

Theses

This thesis has a two-fold objective. One, to develop a suitable testing apparatus in the labaratory to simulate the effect of field pumping of concrete and two, to conduct some preliminary tests to investigate the feasibility of the testing apparatus.

Pumping of concrete has been practiced in the U.S.A. since 1930. The behaviour of concrete in a pipeline has not been studied in much detail while development in the pumping technology raced ahead of the research in this field. Previous studies done in this field have clearly indicated the need for a laboratory simulation of pumping process in order that …

Computational Method For Robot Manipulator Dynamics Based On The Gibbs-Appell Equations, Kwang Bok Kim

Theses

Industrial robots are open-loop multi-degree of freedom mechanisms whose dynamic characteristics are described by nonlinear differential equations. The computations of forces and torques required at each joint of robot manipulator are crucial step for real time control of robot manipulators.

Vukobratovic developed a new computational method for rigid body articulated open-loop mechanisms based on the Gibbs -Appell equations to generate differential equations of motion for spatial open - chain mechanisms. To solve these equations, he introduced the recursive kinematic transformation matrices that represent the motion of each linkage with respect to the base linkage.

Computer programs are developed in this …

Preparation And Properties Of Monomers Derived From Hydroxyhexyl Methacrylate For Dental Adfesive, Ren-Dar Ku

Theses

Although methacrylic acid is the simplest unsaturated carboxylic acid and its hydroxyl ester polymerize readily, yielding useful resins, no adequate study of the preparation and application of the higher hydroxyl alkyl methacrylates has been published. The commercially important hydroxyethyl and hydroxypropyl methacrylates are manufactured from the appropriate alcohol in the presence of sulfuric acid, a method which appears to be less suitable for production of higher hydroxyl alkyl methacrylates. The purpose of the present work was to prepare the hydroxyhexyl methacrylate (HHMA) by a generally applicable method and determine its common physical properties. In addition, the urethane methacrylates were synthesized …

An 8052 Ah - Basic, Based Development System, Suresh Vishwanath Leley

Theses

This project exploits the latest in microcontrollers-an entire environment for developing and prototyping a microcontroller application. With one key chip, a little glue, and a Dumb terminal a powerful system is achieved at a vanishingly small cost. This "one chip" system is adequate for realizing a wide range of applications calling for a small computer or an embedded processor.

Besides economy of system cost, the turn around time from concept to functioning application can be extremely short, even when the development engineer is not particularly well acquainted with traditional assembly language and microprocessor development practices. This economy is achieved by …

An Analysis Of Minimum Shift Keying From The Viewpoints Of Quadrature Multiplexed And Multi-H Continuous Phase Modulation Signaling, Alfred Anthony De Seta

Theses

Minimum Shift Keying (MSK) is a bandwidth efficient modulation scheme which offers superior performance over Quadrature Phase Shift Keying (QPSK) and Offset Quadrature Phase Shift Keying (OQPSK). This paper discusses these modulation techniques from a quadrature multiplexed signaling viewpoint and compares them in terms of error performance, bandwidth properties and bandlimiting and hardlimiting effects. MSK is also considered as a special case of a multi-h Continuous Phase Modulation (CPM) signal and the Viterbi algorithm is presented as an optimal detection scheme for this class of signals. A computer simulation is performed with the VA as the detection mechanism for an …

Reliability Study Of Liquid Crystal Display, Kalpesh Mahendra Desai

Theses

The purpose of this thesis is to study the reliability of liquid crystal display under different temperature conditions. To accomplish this, accelerated life testing was done on the soft glass and the hard glass liquid crystal display units at 77 C and 85 C temperature without any added humidity or voltage.

As the current is a usefu1 indicator for probable wear of liquid crystal display, leakage current was measured at 0 hour, 1000 hours, 2000 hours and 3000 hours when the units have stabilized at room temperature.

The date shows higher spread for the hard glass units. This may indicate …

The Effect Of Toxic Substances On The Index Properties Of Soils, Ronald Dicola

Theses

Contaminated soils were tested to determine if a relationship existed between their index properties and hydraulic conductivity. Atterberg Limit tests and Particle Size Analysis tests were performed on Woodbury, Raritan and Brunswick formation soils. The chemicals examined were Benzene, Phenol and Trichloroethylene (TCE). Tests were performed following the ASTM Standard Test Methods with only slight modification to accommodate the use of contaminated soils. Two different methods of soil contamination were used, one for chemical solutions and the other for pure chemicals.

Particle Size Analysis tests were performed both with and without dispersing agent. Hydrometer tests with dispersing agent resulted in …

Cybernetic Theory Applied In Production Control, Ding-Hsin Fang

Theses

There are many theories for the control of production. Also. there are many successful cases for each of the different theories.

Cybernetic theory is quickly evolving as a design basis for management control systems. Cybernetics is the science of self-regulation and its basic tenents are control, or the ability to direct action toward a predetermined goal, and communication, or the ability to send and receive information.

The objective of this thesis is to identify and discuss this theory applied to the management techniques of production control for a Far Eastern textile firm and to investigate the extent that the firm …

A Computer Aided Manufacturing System For Small Quantity Prototype Board Production, Santiago Garcia-Perez

Theses

A matrix addressed manufacturing tool has been built, tested, and integrated in a system aimed to exploit wire-wrap wiring technology for protoboard production in small quantities. Extensive software exploits the power and economy of the personal computer as a superb manufacturing tool and documentation system. Computer graphics are used as a visual aid that takes advantage of the cognitive capabilities of the human mind and eliminates the boredom and high costs involved with heavy automation achieving instead a tolerable level of human engagement with significantly increased efficiency. The approach presented is new and delivers substantial gains in productivity. The software …

Splchk: A Vax/Vms Spelling Checker And Corrector Utilizing A Trie-Structured Dictionary, Roman George Lewyckyj

Theses

This paper presents a "user-friendly" spelling checker and corrector written in C, which utilizes a "trie" structure to store its main dictionary of words, thereby eliminating redundancy of letters. The program allows the user to either check the spelling of words or files, or to correct "misspelled" words in files. The program is designed to operate primarily in a minicomputer environment, such as the VAX/VMS environment.

The Design And Construction Of Furniture For Mass Production, Kevin Stark

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Micro Computer Animation, Peter Sterling Franks

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Fiber Optic Garments, Heather Pedersen

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Not Included

Collage, And Transposing Space, David King Werberig

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An Analysis Of Variation In Response Time Of Cpu Scheduling Algorithms As A Function Of Load: A Simulation, John Dehority

Theses

This thesis analyzes a group of cpu scheduling algorithms on the basis of the variation in response time that results from changes in the system load. The results of this study quantify the differential degradation of performance across job categories. The job categories include short-burst interactive jobs as well as cpu intensive jobs. For each job type, measurements were made of average job turn-around time, weighted average turn-around time, and worst case response time. Additional statistics gathered include: ready-to-run queue size, cpu utilization and throughput. The three cpu scheduling algorithms compared are round-robin, shortest-job-first, and a multi-queue priority scheduler. The …

La Bella Del Interno, M. Renee Kroner

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Genre Painting: Personal Significance Of The Environment, Leslie Loving

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Diva, A Data Flow Language, Edith Lawson

Theses

The underlying principles of concurrency and data flow are summarized along with a survey of the current data flow languages. A high level data flow language, DIVA, is developed that provides the basic data types and language constructs of traditional languages as well as some unique features of data flow. The organization and data structures of the compiler and assembler are also discussed.

Diverse Realities, Julia Dutton Peterson

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Not Included

Moody Atmosphere Of The Self, Kurt Ruff

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Not Included