Digital Commons Network^™

The Cocoa Rehabilitation Project In Ghana, Kwane Boakye Dankwah

Theses

Several studies have been done in an attempt to find out the cost involved in establishing an acre of cocoa farm and most of these used the questionnare method to gather the information. However, most data gathered this way did not include detail establishment cost information on inputs as the farmers relied on recollection of cost they incurred.

The study done by C. Okali at Dominasi in the Brong Ahafo Region did not follow this pattern. Data collection for this study was started in May 1971 and ended in September 1972 and there were 45 farms involved. This sample was …

A Study Of Hazardous Wastes Generated In New Jersey With Regard To The Siting Of Waste Disposal Facilities In The State, Shreerang Narayan Dharasker

Theses

The effective treatment and disposal of hazardous wastes is one of the most urgent problems facing the State of New Jersey today. New Jersey is the most densely populated state and is a leader in industry. Nearly every major industry in the nation is represented by one or many production units all of which generate copious amounts of hazardous and toxic wastes each year. Although the state has the toughest rules and regulations on the management of hazardous waste, there are very few options exercised or facilities cited for the effective treatment and disposal of wastes within the state boundaries. …

Substructuring Analysis For Impact Dynamics Using Ansys Finite Element Package, Chang Ho Cho

Theses

This thesis is intended to serve as an introductory guide to ANSYS finite element package for the analysis of impact dynamics. Substructuring technique has been used to reduce the degrees of freedom.

Finite element method is essentially a numerical technique to calculate elastic deformations. However, by introducing some techniques like gap element, the technique can be easily extended to rigid body dynamic analysis. To solve the equation of motion both for rigid body and elastic deformations, direct integration technique is used in this thesis, i.e., Houbolt method.

ANSYS is a large scale general purpose computer program for finite element analysis. …

Emergency Stop Devices And The Human Factors Of Response, Robert Paul Guinter

Theses

The manual emergency stop Was recognized as an im- portant aspect of machine control very early during the history of powered mechanical systems. The purpose, of course, was to allow machinery to be quickly stepped during emergencies to minimize equipment damage and/or personal injury. Today, however, the emphasis of control is being shifted more and more toward totally automatic systems. Often, the importance of manual emergency stopping and override of these systems is lost in the zeal to perfect automatic controls. The problem that evolves is how and when to provide an efficient human-machine interface to allow a manual emergency …

Circular Plate Analysis Using Finite Element Method, Shyh-Rong Chiu

Theses

The ANSYS computer program is the application of finite element methods to large-scale engineering problems. In this work the ANSYS program has been employed to solve the circular plate under uniformly loaded with various boundary conditions as follows: (1) clamped along entire edge, (2) simply supported along entire edge, (3) clamped at several points along the boundary, (4) simply supported at several points along the boundary, and (5) simply supported 36 points with 4 points clamped..

The results obtained from the ANSYS program illustrated that the finite element method has no boundary conditions constraints and presents good approximations to the …

Fracture Energy And Tensile Behavior Of Concrete, Wen-Jinn Chiou

Theses

Fracture behavior of concrete has been a subject of investigation for the past two decades. The need of understanding the complete tensile response of concrete is absolutely essential for theoretical modelling as well as design application of plain concrete structures.

In this study, attempts were made to investigate the validity of two important fracture parameters, namely, the fracture energy and the critical crack tip opening displacement. Three types of test specimen, dog- bone shaped tension specimen, notched beam and compact tension specimen, were investigated. These tests were conducted using the closed-loop MTS 810 strain-controlled testing system. For the uniaxial tension …

A Research Study To Determine The Characteristics And Attitudes Shared By Entrepreneurs And Intrapreneurs And The Similarities And Differences Between Them, Miguel A. Vargas

Theses

The United States of America has been the mecca of many ventures for people with vision, goals and perseverance. The prosperity of our nation has been paved by individuals with great ambition, determination and insight, who have dared to take on a risk in owning a business enterprise.

This research study was conducted to determine the characteristics and attitudes of both entrepreneurs and intrapreneurs, as well as the similarities and differences between them.

For this study, a survey of entrepreneurs.was conducted through the use of questionnaires distributed to business owners located in the counties of Essex, Passaic and Hudson, in …

Reliability Studies On Solid Tantalum Electrolytic Capacitors By Means Of Accelerated Life Tests, Venkata R. Golthi

Theses

The purpose of this thesis is to understand the failure mechanisms in Solid Tantalum Capacitors encapsulated in plastic, and to suggest the precautionary measures that prevent the occurrence of these failures.

The reliability of Solid Tantalum Capacitors encapsulated in plastic is of considerable interest because in some applications where the mechanical accelerations or shocks are considerable the "better" "hermitically" sealed type are not able to sustain themselves. Poor adherence between the dielectric film and the base metal Tantalum under the conditions of sudden mechanical shocks, causes problems.

Our study was carried out in two different directions, theoretical and experimental. The …

Osmotic And Mean Activity Coefficients Of Cacl2, Nai, Libr And Licl In Ethanol At 50 Degrees C, Gregory J. Czerwienski

Theses

Vapor pressure depression data for CaCl₂, NaI, LiBr, and LiCl were measured at a molality ranging between 0.2-7.5 depending on the solubility of the salt in ethanol. Data were also measured at 35° C for the LiCl. The apparatus used was a recirculation still of the Othmer type.

Osmotic coefficients were calculated from the total pressure of the system. The one parameter Bromley equation and the three parameter Pitzer equation were used to correlate the data. For all the systems, the Pitzer equation correlated the data better as one would expect. Mean activity coefficients were calculated graphically and …

Biodegradation Of Mixed Phenolic Substrates, Prasad Gonnabathula

Theses

The biological degradation of phenol, with either 2-chlorophenol, 2,6-dichlorophenol, or nitrobenzene as cosubstrates was studied in aerated five - liter batch reactors using mixed liquor from the Passaic Valley Sewarage Commissioners wastewater treatment plant (Newark, NJ). The initial substrate concentrations were: 100 – 150 ppm phenol, 10 - 20 ppm 2-cp, 10 ppm 2,3 dcp, and 10 - 20 ppm nitrobenzene. The concentration vs. time data were fit to three kinetic models: zero-order, first-order, and Monod(assuming constant biomass). Most of the data were best fit by either the Monod or zero-order model. For all compounds tested, biodegradation was the primary …

Physical And Mechanical Properties Of A New Type Of Polymer Concrete, Kyan Bin Khoo

Theses

A new type of Polymer concrete is an admixture of a special Latex, Portland cement and Sand. It has high bond strength, quick curing, durability and adequate strength. The Mechanical and Physical properties were investigated in this paper. Reinforcement with Glassfiber was done and its properties compared to those of control specimens. The heat generation in Polymer Concrete (PC) and its relationship with the properties of PC was also investigated.

A new type of Polymer concrete is an admixture of a special Latex, Portland cement and Sand. It has high bond strength, quick curing, durability and adequate strength. The Mechanical …

Dispersion In The Laminar Flow Of Ellis Model Fluids Through Straight Tubes, Yeong-Hua Huang

Theses

Taylor-Aris dispersion theory is extended to the laminar tube flow of Carreau model fluids and Ellis model fluids and the results are compared with those of power law fluids. It is found that Carreau and Ellis models are more appropriate than power-law model, especially at low pressure gradient.

An exact solution to the unsteady convective diffusion equation in fully developed laminar flow in tube is obtained by applying the generalized dispersion theory of Gill and Sankarasubramanian for Ellis model. The results are compared with those obtained by Booras and Krantz for power-law model. The most interesting result of this work …

The Separation Of Proteins Via Charged Electromembrane Process, Chi-Wen Lin

Theses

A new method for separation and concentration of protein and other biocolloids such as hemoglobin and albumin was developed by a process called the charged electromembrane (CEM) process. The process is characterized by using a metallic membrane as a filter which can carry either positive or negative electric current.

The effect of various factors on the separation coefficient and filtration efficiency were investigated experimentally. These factors include strength of electric field, pH of colloidal solution, electric current through membrane filter and flow rate.

It was found out that the thickness of the gel layer formed on the membrane could be …

Prediction Of Vapor And Liquid Equilibrium Properties For 25 Organic Priority Pollutants In Aqueous Solution, Pinchieh Pai

Theses

Activity coefficients and Henry's law constants for 25 organic priority pollutants were estimated using UNIFAC thermodynamic calculations. For 6 of these compounds, the results were compared with measured values reported in the literature. This indicated errors in the UNIFAC predictions varying from 24.0% to 95.0%. Best results with UNIFAC were obtained using liquid-liquid equilibria, rather than vapor-liquid equilibria.

Octanol/water partition coefficients were also estimated for the same 25 organic priority pollutants using the fragment constant method. Results differed from values reported in the literature by 5% to 170%.

Estimated activity coefficients were also used to predict stripping rates of organic …

Biodegradation Of Phenol And 2-Chlorophenol Using A Fill-And-Draw-Reactor, Chi-Chun Tsai

Theses

The biological degradation of phenol and 2-chlorophenol was studied at room temperature in a microprocesser controlled fill-and-draw reactor using activated sludge from the Passaic Valley Sewerage Commissioners wastewater treatment plant (Newark, New Jersey). The reactor was cycled through four unit processes: fill, react, settle, and draw. Different cycle times were tested, and the system response was characterized by dissolved oxygen measurements and substrate analysis (by gas chromatography).

With inhibitory substrates, such as those tested, this reactor had much more flexibility, and was therefore much easier to operate, than a standard continuous flow reactor.

Comparison Of Several Manufacturing Techniques Used To Produce A Sterile Antibiotic Powder, Antonio Joseph Barberio

Theses

There are several manufacturing processes (crystallization, spray drying, freeze drying, and closed crystallization) that are used to produce a sterile antibiotic powder. A pharmaceutical manufacturer is faced with the problem of deciding which process is best suited for their operations. The purpose of this thesis is to propose a comparison technique that might aid in a solution to this problem. In the first step of the comparison technique, a fixed rating is assigned to a number of different categories (i.e. initial cost of equipment, product purity, etc.) for each process. The fixed ratings were established from an industrial survey, and …

Effect Of Humidity And Moderate Temperature On Microcircuit Failure, Antoine Mikhayel Chaia

Theses

The increased use of microprocessors has brought forth many questions concerning the reliability of these devices.

This research discuss the TTL integrated circuit failure rates, and provides information on the effects of temperature, device complexity and packaging on TTL failure rates under storage condition of 100% R.H. (Relative Humidity) and 100°C and no added humidity at 100°C. Other factors which can affect failure rate are also discussed, including designs, materials process.

Approximately 200 microcircuits of TTL (74LS00) were subjected to extend life testing at 100°C; where 125 chips are tested at 100°C ± 2° and no added humidity and the …

Nervous System Simulation, Jian Chen

Theses

This thesis deals with the nervous system simulation. The Hodgkin-Huxley model and Stein's model are used as basic tools. The author has tried to describe some practical problems by mathematical models.

First, the horse-shoe crab eye is investigated. Light intensity is reported to the brain by the firing frequency of the photoreceptoe. A Poisson process is used to simulate the stimulus to the receptor. The result of the stochastic model coincides with the theoretical one: receptor overlapping decreases the resolving power of the eye; and the lateral inhibition compensates the effect of overlapping.

Second, a nerve muscle model was set …

Pozzolanic Admixtures In Concrete Mix, Ronghao Chen

Theses

Fly ash and condensed silica fume are two main mineral pozzolanic admixtures in portland cement concrete. The increasing use of the fly ash in concrete projects and concrete products during the past 3O years and condensed silica fume in several projects during the past 1O years indicates a greater acceptance of them as the mineral pozzolanic admixtures in concrete. Although the engineers are of some identical views in using these industrial byproducts in concrete projects, there are different views on how the behavior and utilization of fly ash con-crete and condensed silica fume concrete since the byproducts are not the …

The Issues Facing Filipinos In The U.S. Health Care Industry, Laleh Amighi

Theses

In this paper the involvement of minorities in the health care industry is examined. In particular, Filipino minorities working in nursing homes throughout the U.S. are studied. The various aspects of the lives of these workers and their relationship with the health care industry are analyzed and discussed in detail. These include the workers' legal status, pay scale, working environment and the pertinent legislative laws and regulations. A good deal of attention has been paid to the management-employee relationship and the duties and responsibilities of each party. Another entity affecting this relationship is the labor union; thus, the role and …

A Closed Form Image Force Function For Deposition Of Particles In A Cylindrical Tube, Hsi-Chung Chiou

Theses

This study investigated the behavior of charged particles suspended in a laminar steady incompressible flow in a cylindrical tube under the influences of image , inertia , viscous and gravitational forces. A new expression for the image force was obtained by introducing an approximate potential energy function. The velocity profiles employed in the analysis were uniform and parabolic.

The governing equations derived were based on Newton's second law of motion and were solved by a Runge-Kutta numerical method. The results were obtained for different values of Q, a dimensionless inertia-charge parameter. For a value of Q equal to zero the …

On Torsional Spring Constants At The Juncture Of Piping-Nozzle, Shean-Juinn Chiou

Theses

Numerical results of torsional spring constants at the juncture of piping-nozzle are studied in this thesis by using the "ANSYS" program and run on VAX computer. These results are presented in tabulated form for a piping-nozzle vessel with constant thickness of 0.375 in. Plot for the torsional spring constants in terms of beta (nozzle radius/pipe radius), gamma (pipe radius/thickness) and alpha (pipe length/radius) are also presented in this thesis. These data are under zero piping internal pressure with beta ranging from 0.1 to 0.8, and gamma ranging from 10 to 150. A numerical example with verification is also given.

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 …