Engineering Commons^™

Reliability Of Dielectrics : Using Noise As A Diagnostic Tool, Ramesh K. Jain

Theses

The aim of this thesis is to develop a screening method to predict the reliability of a dielectric material. The screen chosen is an electrical noise. The dielectric material studied is varnished fibre glass cloth material supplied by Westinghouse Electric Corporation.

The dielectric material will have varying amount of voids, crystal defects, and surface contaminants impurities introduced during manufacturing process. On application of the electric stress, ionization (corona) will take place. The corona degrades the material due to thermally generated heat, chemical reactions in the voids and ionic bombardment of the material.

An experimental set up is developed to monitor …

Investigation Of Water-Binding Properties Of Industrial Sludges Using Thermal Analysis As A Monitoring Tool, Ron Josephson

Theses

As part of a program to develop new and more cost-effective dewatering approaches for industrial hazardous wastes, sludges and synthetic "model" materials were analyzed by thermal methods in an attempt to comprehend their water-binding qualities and differentiate free and bound water. These thermal methods included Differential Thermal Analysis (DTA), Thermogravimetric Analysis (TG), and Differential Scanning Calorimetry (DSC). Industrial sludges and laboratory models were compared using both standard heating techniques and subambient cooling (to -60°C). This latter technique provides direct indication of the amount of free water. This information can be very useful in evaluating and improving dewatering techniques for industrial …

The Modeling Of A Self-Oscillating Dc-To-Dc Converter, Frank Andrew Linkowsky

Theses

This thesis develops a model of a nonlinear self oscillating current-or-voltage step-up dc-to-dc converter. Expressions are given that predict the operation of the converter in the time domain and in the state plane. To verify these expressions, a large signal computer simulation technique [1] is used to compare theoretical results with actual measurements. This type of simulation allows a nonlinear switching converter to be modeled with a series of piecewise-linear operating intervals. The resulting waveforms predicted by the developed model show close agreement with waveforms found in the laboratory. Therefore, the model represents a powerful tool that may be used …

Tests On Square Reinforced Concrete Members Under Combined Biaxial Bending And Tension, Bhadresh Shah

Theses

The research reported herein studies the ultimate strength behavior for square-shaped reinforced concrete short columns under combined biaxial bending and tension that is a common design problem. The present ACI building code (ACI 318-83) (1) and design hand book (2) do not offer an insight into the determination of strength and ductility behavior of biaxially loaded reinforced concrete columns. A design equation developed by Hsu (3,4,5 ) to study the ultimate strength behavior and failure surfaces for members under these combined action was used and the computed results were compared with the present analytical results and experimental results for square-shaped …

Theoretical Investigation Of Submerged Turbulent Jet, Talal N. Hindi

Theses

A theoretical investigation concerning the flow characteristics velocity distribution of a circular submerged turbulent axisymetricic water jet impinging on a flat plate was carried out. Starting with the use of the available data and equations obtained by previous investigators and found room for improvement. By solving these equations for the velocity distribution and comparing them to the experimental results is was found out where improvements of the analysis were were necessary. Then taking Tollwien's solution for the velocity distribution and changing the reference axis to see whether or not the equations would give better results for velocity calculations. With certain …

A Tracheoesophageal Puncture Voice Prosthesis, Georghios Makris

Theses

A voice prosthesis was developed that allows verbal communication of laryngectomised patients. The prosthesis requires a superiorly directed tracheoesophageal puncture in which the periscope mounted on the tracheal stoma vent is introduced. The prosthesis is operated by air injection through the periscope. Air injection is achieved by pulmonary pressure after the occlusion of the stoma vent. Stoma vent occlusion can be achieved either by the patient's finger or by the designed cover valve mounted on the prosthesis. The cover valve allows free breathing, hand-free prosthesis use, and it can release excess pressure during coughing. Periscope valve air resistance tests have …

A Theoretical Study Of Pure And Simple Competition Between Two Microbial Species In Configurations Of Two Interconnected Chemostat, Cheng-Ming Kung

Theses

It is known that two microbial populations competing purely and simply for a common substrate cannot coexist in a steady state in an environment which is spatially homogeneous. Hence they cannot coexist in a chemostat something which implies that a mixed culture of two pure and simple competitors cannot be maintained in a single ideal reactor in a steady state. The present study investigates theoretically pure and simple competition between two populations in two interconnected chemostats. Three reactor configurations are considered and analyzed. It is proved that two pure and simple competitors can coexist in a steady state in both …

In Vitro Comparative Hydrodynamic Study Of Heart Valve Bioprostheses Under Accelerated Fatigue Conditions And Under Physiological Conditions, Mario Cincinat Iosif

Theses

The present study involves the use of an accelerated fatigue testing system*, and a pulse duplicator (heart simulator)*, to evaluate the hydrodynamic characteristics of cardiac bioprostheses.

The hydrodynamic performance of these prosthetic valves is compared when tested using each machine, in order to assess the determining conditions that exist for each case, and try to correlate them.

Pressure drop and pulsatile flow across valves are measured, using a real-time on-line data acquisition system, which includes, in addition to the fatigue tester and the pulse duplicator, a DC amplifier, an analog-to-digital converter and a digital microcomputer. Special acquisition software has been …

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 …

Systems Building Theory Application Within The Residential Housing Construction Market, Gary Alexander Newhard

Theses

The primary purpose of this report is to introduce the economical value in utilizing certain "systems building" applications. In this report I focus on integrated system methodologies that encourage residential building economy and submit such systems as a viable alternative to traditional labor intensive housing construction. The consumer market that could be particularly enhanced by these systems ranges from low income to middle income and the by-product would be classified as "affordable" housing.

This report focuses on the New Jersey real estate market and presents certain prefabricated housing systems as an economical means of meeting the large demand for residential …

Modal Analysis Of A Cantilever Plate, Ohseop Song

Theses

This thesis discusses the vibration of a thin, flat cantilever aluminum plate. Results are based on both an analytical finite element method using the ANSYS program and an experimental analysis using a digital Fast Fourier Transform (FFT) analyzer. The FFT analyzer permits extraction of modal parameters (natural frequency, damping, mode shape) for the plate.

Measurements Of Basic Semiconductor Properties, Abdolreza Ariantaj

Theses

Mobility, resistivity, and total impurity concentration of several purchased p-type silicon samples with known resistivities were measured by Hall effect, experiments utilizing the Van Der Pauw method. The silicon samples will serve as Hall effect standards for future measurements on other semiconductor materials, particularly gallium nitride ion cluster beam (ICB) deposited thin films. The samples which were Freshly etched with hydrofluoric acid had measurement values of 455 cm ² / V.sec, 45.9 Ω cm, and 2.6 X 10¹⁴ cm³ for mobility, resistivity, and total impurity concentration, respectively. The mobility values were within 9.9 per cent, of the published values …

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. …

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 …

Introductory Guide To Bridgeport Series I Cnc Milling, Drilling And Boring Machine, Apurva Vinodchandra Doshi

Theses

This thesis is intended to serve as an easy introductory guide on how to work with Bridgeport Series I CNC Milling, Drilling and Boring machine. An attempt has been made to make the subject matter simpler to give the reader a good start in programming and operating this machine

The spectrum of technological implementation of CNC machine tools is extremely broad,. Companies utilizing advanced technologies such as computer graphics, DNC and Group Technology are in this field for some time. Even small shops are getting equipped with CNC machine tools. The present CNC systems, which are less costly, more reliable …

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 …

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 …

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 Kinetics And Mechanism Studies Of A Polymer Powder Coating On Metal Surface By Cathodic Electrodeposition Process, Wen-Lin Wu

Theses

A polymer dispersion of fluorocarbon with solid constent in the range of 10-25% were prepared from white powder polytetrafluorethylene (PTFE), emulsifier combination of dodecylbenzyldimetlyl sulfonium chloride and Trition N-150, and other components or additives. Such a fluorocarbon dispersion is very stable against coagulation and has a pH in the range of 8-10, which is especially suitable for powder coating purpose.

A new electrocoating technique, which is called cathodic electrodeposition powder coating method, was conducted in this study. This new coating method includes four steps: pretreatment, electrocoating, drying and baking. Two kinds of degreased metal substrates, aluminum and steel plates, were …

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 …

The Effects Of Different Administrative Parameters On Learning In A Management Simulation, Stephen Christopher Betts

Theses

This research puts forth a set of conclusions regarding the relationship between how a full scale interactive and competative management simulation is organized and executed and how effective the experience seems to participants. One hundred sixty students who participated in management simulations in five different schools were questionaired about how effective the simulation was in teaching ten different subject areas. Their instructors and other game administators were interviewed to Find out how and why the simulation was organized and executed the way that it was in their school. The simulation used in all five samples was the Tempomatic IV. The …

Modelling Of Pile Load Tests In Weak Rock, Daniel Walter Caruso

Theses

The purpose of this thesis was to investigate the loss of load capacity of relaxed pile groups driven into weak bedrock. This was accomplished in the laboratory using a dynamic driving apparatus equipped with a static load testing system. The static load testing system applied loads hydraulically, and the load settlement behavior was monitored using an electronic load cell and a linear variable differential transducer (LVDT).

Tests were performed using 1" diameter steel pipe piles driven in a five pile group pattern at spacings of two diameters and four diameters. Piles were driven into a simulated rock mass consisting of …

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 …

Utilization Of The Microcomputer To Improve The Productivity Of Small Manufacturing Companies, Hung-Gi Chang

Theses

The ongoing microcomputer development has led to its increasing application in manufacturing to reduce costs and improve productivity. Being more aware of this technology, most of these benefits have accrued to large firms. The intent of this thesis is to show that it is equally advantageous for small manufacturing companies to utilize them and show how they can do so.

The paper discusses the role and characteristics of microcomputers. Available software to do engineering designs, materials requirements planning, process planning, and master production scheduling is described. Using a case study a method that can be followed in selection and implementation …

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 …

Pressure Drop In A Strainer Element By The Finite Element Method, Wei-Long Chen

Theses

The pressure drop in a strainer element which consists of a channel and a diffuser has been investigated by the finite element method and the semi-empirical analysis.

An existing finite element program, FEM2D using the penalty parameter model, was employed. It was found that the range of Reynolds numbers in the strainer element was 0.193 to 4.824. For the pressure drop in the channel, the finite element method is in agreement with the analytical solution. For flow in the diffuser, the finite element method failed to give satisfactory results due to flow separation.