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Cad/Cam : An Analysis And Application To An Industrial Environment, Kulendu Vyas May 1990

Cad/Cam : An Analysis And Application To An Industrial Environment, Kulendu Vyas

Theses

This work is intended to explore details of CAD/CAM techniques and to check its application in medium size industry. To achieve this goal, a thorough study has been carried out on current CAD/CAM techniques, keeping in mind it's requirements, source and application, considering both the hardware and software side of it. To check application of CAD/CAM in an industrial environment, Schering Plough corporation was chosen as a subject. The main theme behind this application to the Schering Corp. was to develop the CAD/CAM capability within company, in order to gain better control over the quality and productivity, and to reduce …


Computer-Aided Planning For Automatic Assembly Of Printed Circuit Boards, Qin Xiang May 1990

Computer-Aided Planning For Automatic Assembly Of Printed Circuit Boards, Qin Xiang

Theses

A study of printed circuit board assembly in the context of process planning and optimization of assembly motion is presented. A knowledge-based system is developed utilizing software packages VP-Expert, dBase 3 for the Universal automatic assembly machines. The planning of time-optimal assembly motion falls into the travelling salesman problem whose solution is obtained using a composite algorithm. Branch-and-bound algorithm is also discussed for solving the travelling salesman problem.


Automatic Infrared Inspection Of Solder Joints On Mounted Circuit Boards, Ken Kekuan Zhou May 1990

Automatic Infrared Inspection Of Solder Joints On Mounted Circuit Boards, Ken Kekuan Zhou

Theses

This thesis reports the research work on automatic infrared and visual light inspections of solder joints on printed circuit boards (PCBs) utilizing an image processing system and statistical pattern recognition techniques.

A small scale image processing system, consisting of a SUN workstation and several DATACUBE modules, is set up for the research. Software packages for imaging, displaying and solder joint inspection are developed and ready for public usage.

The capability of infrared inspection for solder joints on PCBs is demonstrated. The fusing of infrared and visual light imagery for the inspection is shown to offer better results than that obtainable …


Biodegradation Of Phenol By Two Competing Microbial Species In A Sequencing Batch Reactor, Yoo-Suk Ko May 1990

Biodegradation Of Phenol By Two Competing Microbial Species In A Sequencing Batch Reactor, Yoo-Suk Ko

Theses

Biodegradation of a single pollutant by two competing microbial species has been mathematically described for the case where a sequencing batch reactor is used. The model has been solved numerically to predict the behavior of the reactor under different operating conditions and for different kinetic expressions for biodegradation.

Experiments were performed to verify the predictions of the model. Serratia marcescens (ATCC 17991) and Pseudomonas putida (ATCC 31800) were the species used. Experiments were first performed in order to reveal the kinetics of biodegradation for each individual species. The biodegradable substance used was phenol, which was the sole carbon source in …


Impacts Of Treated Municipal Waste-Waters On Development And Growth Of Hudson-Raritan Estuary Fishes, Chien-Min Chen May 1990

Impacts Of Treated Municipal Waste-Waters On Development And Growth Of Hudson-Raritan Estuary Fishes, Chien-Min Chen

Theses

The Hudson—Raritan Estuary, known as one of the worst polluted estuaries in the world, receives pollutants from many point sources. Treated municipal wastewater (TMW) counts for 13% of its total freshwater input and more than 98% of the chemicals classified as priority pollutants been infused. Because of the complexity of the input, treatment facilities cannot remove toxicants efficiently. In addition, generation of new compounds by water treatment such as chlorination occurs. Batch-to-batch variability in the chemistry of this effluent was reflected in the early life stage toxicity bioassays using mummichog (Fundulus heteroclitus) and winter flounder (Pseudopleuronectes americanus) embryos.

TMW has …


Thermal Desorption Of Hazardous And Toxic Organic Compounds From Sand Matrices, Jaeil Kwon May 1990

Thermal Desorption Of Hazardous And Toxic Organic Compounds From Sand Matrices, Jaeil Kwon

Theses

Incineration processes are effective and sometimes efficient technologies for the remediation of contaminated solids which result in permanent destruction of most organic hazardous compounds. A less energy intensive, but more efficient process to remove contaminants from the soil is the application of heat and a flow of inert gas where the entire soil mass is not heated to incineration temperatures. This thermal treatment increases volatilization and often effects complete removal of organic compound depending on soil conditions and species volatility,

The goals of this research are to develop an understanding of the mass transport phenomena and adsorption thermodynamics that control …


A Comparison Of Integrated And Differential Estimates Of Flourescent Intensity Profiles Using Digital Video Image Analysis, Langfang Wu May 1990

A Comparison Of Integrated And Differential Estimates Of Flourescent Intensity Profiles Using Digital Video Image Analysis, Langfang Wu

Theses

The dynamics of macromolecular transport across microvascular walls in the hamster cheek pouch have previously been studied by other investigators using fluorescence intravital microscopy. Fluorescein Isothiocyanate labeled Dextrans (FITC-Dx) of 20,000, and 70,000 molecular weight (FITC-Dx-20 and FITC- Dx-70) were used as macromolecular probes. Values of fluorescent intensity were previously recorded on videotape as a function of distance perpendicular to leaking vessels over a period of about 2.5 hr to allow for tracer equilibration in the interstitial space. In this study, these videotapes were played back frame-by-frame and 215x130-pixel windows around each leaking vessel were selected for further analysis of …


Mathematical Modeling And Computer Simulations Of Biodenitrification In Batch And Sequencing Batch Reactors, Sugata Sanyal May 1990

Mathematical Modeling And Computer Simulations Of Biodenitrification In Batch And Sequencing Batch Reactors, Sugata Sanyal

Theses

Mathematical models have been derived for describing biodegradation of ni¬trate and nitrite in an anaerobic environment. Monod model for nitrate and Andrews model for nitrite were used as kinetic models. Experimental data from literature suggest that nitrate is not an inhibitory substance, while nitrite is not only inhibitory but it may also have a toxic effect on the biomass. The models were brought in dimensionless form in order to reduce the number of parame¬ters. Biodegradation was mathematically described for a batch, and a sequencing batch mode of operation. Computer programs were developed for numerically simulating the process. Some of the …


The Oxidation Of Methylene Chloride Over Manganese Dioxide Catalyst, Jun Du May 1990

The Oxidation Of Methylene Chloride Over Manganese Dioxide Catalyst, Jun Du

Theses

This research presents results from a study with the goal of using a transition metal oxidation catalyst, manganese dioxide (MnO2) I to convert low concentrations of methylene chloride (CH2Cl2) in air and in a methane/air stream into CO2, H2O and HCl. Our objectives were to determine the oxidative effectiveness of the catalyst and its durability under the corrosive exposure to chlorine, HCl and other likely stack gas contaminants.

Experiments were carried out in a tubular packed bed integral reactor using gas chromatographic (FID and TCD) analysis for chlorocarbons and non-dispersive …


Removal Of Nitric Oxide From Flue Gas With Ferrous Cysteine Solutions, Chun-Chiao Chou May 1990

Removal Of Nitric Oxide From Flue Gas With Ferrous Cysteine Solutions, Chun-Chiao Chou

Theses

The removal of NO from flue gas with aqueous ferrous cysteine solution as the reducing agent was discovered by S. G. Chang et al. (1988), at University of California, Berkeley. The purpose of this research is to extend the experimental works done by Chang et al., and to find methods to minimize the problems associated with the sensitivity of the medium to oxygen gas and emission of nitrous oxide, a greenhouse gas. The main objective was to determine the feasibility of using ferrous cysteine in the treatment of NOx emissions from incinerators. In the present study, it was found that …


Finite Element Stress Analysis Of Engine Piston, Anil Nanalal Mistry May 1990

Finite Element Stress Analysis Of Engine Piston, Anil Nanalal Mistry

Theses

In this analysis, Ford Motor Company's, modular engine seriespiston was selected for the analysis purposes. The engine has a capacity of 4.6 liter, V-8 cylinder and with 2 valves.The piston is made of aluminum alloy material Z-16-T6. A three-dimensional finite element model was created to analyze the piston. The model, which contains only the quarter section of the piston due to loading symmetry and geometry, was used to calculate operating temperatures and the corresponding thermal expansion. Operating stresses due to thermal and mechanical loads were also calculated. The accuracy of the model was verified by material data published in the …


Modeling Packed Bed Catalytic Reactors, Jing Yang May 1990

Modeling Packed Bed Catalytic Reactors, Jing Yang

Theses

Catalytic reactors provide a potentially important tool in the control of process emissions to the environment. This work provides a detailed chemical/physical model for analysing the operational characteristics of packed bed catalytic reactors. Mass, momentum, and energy conservation equations are written for the gas and solid phases. Heterogeneous and homogeneous reactions are used to convey the required stoichiometry, reaction rate, and heat release rate. Reaction in each phase is modeled as a one-step, global reaction. Heat and mass transfer, fluid friction, and axial heat conduction in the solid phase are modeled using suitable literature correlations. The resulting non-linear, first-order differential …


A Theoretical Model For Radio Attenuation Inside Buildings, Kyu-Sung Kim May 1990

A Theoretical Model For Radio Attenuation Inside Buildings, Kyu-Sung Kim

Theses

Research to expand the capability of indoor, portable, radio frequency links for voice and data transmission is being pursued worldwide. Sophisticated communication systems using digital portable radio telephones have been proposed. To accomplish this goal, it is necessary to ascertain the attenuation of electromagnetic signal propagation inside buildings. Because modeling of the indoor environment at radio frequencies is very complicated, most publications document experimental results. In this study,. a theoretical model is proposed for predicting path loss inside buildings. The theory involves a waveguide model of the indoor environment which permits a rigorous modal solution similar to that developed by …


Development Of Air-Break Circuit Breaker, Ravi Kanth Korrapati May 1990

Development Of Air-Break Circuit Breaker, Ravi Kanth Korrapati

Theses

This thesis describes the development of an Air-Break circuit breaker, for Heinemann Electric Co., New Jersey, using I-DEAS CAD software. The physical properties obtained from the software, for the components of the armature assembly and the contact arm and the carriage, are used in determining the initial forces on a helical delay spring and in calculating accelerations of links in the trip mechanism. The trip mechanism is a four-bar mechanism with a spring as a coupler. Two second order differential equations define the motion of its links, the contact arm and the carriage. A time history of the links is …


Chemical Activation Analysis Of The Reaction Of Methyl, Ethyl, Propyl And Butyl Radicals With O2, Hsing-Hui Yu May 1990

Chemical Activation Analysis Of The Reaction Of Methyl, Ethyl, Propyl And Butyl Radicals With O2, Hsing-Hui Yu

Theses

The addition reactions of methyl, ethyl, propyl and butyl radicals with molecular oxygen to form the energized adducts CH3OO#, CCOO#, CCCOO#, C2COO#, C*CCOO#, CCCCOO#, CCCOO.C#, C2CHCOO#, C3C00#, C*CCCOO#, CC*CCOO# and C*CCOO.C# and the reactions of the adducts to varied products have been analyzed using the bimolecular version of the quantum Rice-Ramsperger-Kassel (QRRK) theory. The analysis encompassed a temperature range from 200 to 2000 K and pressures between 0.001 to 10 Atm in argon (CH3 + O2 reaction only), helium and nitrogen bath gases. The calculations satisfactorily explain the experimentally observed rate constants for loss …


Investigation Of Material Erosion By Abrasive Water Jet Cutting, Fang Hu May 1990

Investigation Of Material Erosion By Abrasive Water Jet Cutting, Fang Hu

Theses

This study is concerned with the investigation of material erosion phenomena occurring in the abrasive waterjet (AWJ) cutting process.

A series of scratches were generated by the abrasive waterjet on the polished surface of aluminum samples. The tests were carried out at different traverse speeds, abrasive flow rates, diameters of sapphire nozzles, diameters of carbide tubes and initial abrasive particle sizes. Material volume loss in the erosion zone was measured directly or calculated by the use of the suggested mathematical models. An analysis of experimental results enabled us to introduce a new process criterion, particle distribution density, which determines the …


Simulation Of Random Packing Of Hard Spheres Using Monte Carlo Method, Sung-Ho Park May 1990

Simulation Of Random Packing Of Hard Spheres Using Monte Carlo Method, Sung-Ho Park

Theses

A computer based method of generating a random packing of hard spheres is described. Using a Monte Carlo method as employed in the field of Computational Statistical Physics, packing of hard spheres are generated and analyzed.

The mean packing fractions for the present assemblies of 1000 spheres are 0.555±0.015 after pouring and 0.582±0.018 after 10 cycles of shaking. These values are approximately 5 to 6 per cent lower than the experimental results of G.D. Scott[30], but similar with the result of Visscher & Bolsterli [17].

The mean coordination numbers are 5.97 and 6.33 for the pouring and shaking case, respectively. …


X-Ray Powder Diffraction, Scanning Electron Microscopy And Energy Dispersive Spectroscopy Studies Of Soil Containing Chromium Immobilized By Microwave Treatment, Nagui Ibrahim May 1990

X-Ray Powder Diffraction, Scanning Electron Microscopy And Energy Dispersive Spectroscopy Studies Of Soil Containing Chromium Immobilized By Microwave Treatment, Nagui Ibrahim

Theses

The orientation of soil contaminants such as chromium is altered during microwave heating. The SEM and EDS were utilized in the study. The nature of the orientation is related to the heating time. This results in immobilizing the contaminant in leaching tests. The non-leachibility was related to the reactivity of the chromium salt with the soil hematite phase (Fe2O3) during the microwaving. This was proved By the X-ray diffraction analysis. The spectrums obtained from 30 and 60 minutes microwaved samples were identical in the crystal phases and were significantly different from the contaminated unheated sample.


An Investigation Of The Dynamics Of Abrasive Waterjet Formation, Md. Ekramul Hasan Khan May 1990

An Investigation Of The Dynamics Of Abrasive Waterjet Formation, Md. Ekramul Hasan Khan

Theses

The aim of this research was to investigate the jet formation and the jet behavior, as characterized by the velocity field, the force exerted by the jet on a work-piece and the jet geometry. The velocity and force distributions were measured using a laser transit anemometer (LTA) and a piezoelectric force transducer (PFT) respectively for constant water pressure (334.6 MPa) supply. The jet structure and its instantaneous behavior were visualized by the used of high speed filming. LTA and PFT measuring techniques were established and verified. The measurements were performed under different operating conditions. It was found that at a …


Eeg Mapping Using The Personal Computer, Zhuan-Zhang Pei May 1990

Eeg Mapping Using The Personal Computer, Zhuan-Zhang Pei

Theses

An approach for brain electrical activity mapping using a personal computer has been investigated to enhance the visibility of the EECs. An automatic procedure from data acquisition to the final mapping has been developed for on-line or off-line data processing, in which a table-look-up technique has been introduced to eliminate redundant processing. The power spectra in different EEC frequency bands for four electrodes are coded into 15 colors and mapped on a color monitor. The data correspondings to the areas between electrodes are interpolated by the surface spline method. The mapping speed and smoothness has been optimized. An experiment has …


A Comparative Study Of Cadmium Uptake By Cells Of Gram-Positive And Gram-Negative Bacteria, Shubhangi Rajan Bhende May 1990

A Comparative Study Of Cadmium Uptake By Cells Of Gram-Positive And Gram-Negative Bacteria, Shubhangi Rajan Bhende

Theses

Cadmium uptake by cells of Gram-positive and Gram- negative bacteria was studied. Gram-positive and Gram- negative bacterial cells were separated from activated sludge collected from the Parsippany Troy Hills Water Pollution Control Plant (NJ) by isolating them on agar plates. These were grown separately and used for uptake experiments.

Gram-positive bacterial cells showed 17% more uptake of cadmium as compared to Gram-negative cells at 30°C and pH 6.6. More than 95% of the total cadmium removal from the solution was observed during first 5 min. of cell-metal contact time. In case of Gram-positive bacteria cadmium uptake decreased by 5-10% after …


Mathematical Modeling And Simulation Of The Progression Of Aids, Anju H. Nagpal May 1990

Mathematical Modeling And Simulation Of The Progression Of Aids, Anju H. Nagpal

Theses

Acquired Immunodeficiency Syndrome (AIDS) caused by Human Immunodeficiency Virus (HIV) is a pernicious disease acknowledged as a world health problem. One of the major issues in the study of AIDS is understanding the manifestation and the progression of the disease following the transmission of HIV. Unfortunately, the present state of biological knowledge does not yet give us a reliable means of evaluating these phenomena. A simulation approach is, therefore, extremely useful in predicting the various phases of the deteriorating physiological status of the patient. In the present study we have focused on the development of a mathematical model of the …


Design Of A Real Time Optical Sensor For Continuous Blood Cell Separation, Girish S. Yerande May 1990

Design Of A Real Time Optical Sensor For Continuous Blood Cell Separation, Girish S. Yerande

Theses

For continuous measurement and display of oxygen saturation and RBC content in blood during cell separation a reflection type optical sensor is designed based on the theoretical model using the photon diffusion theory. The prototype sensor consists of two arrays of light emitting diodes, red and infrared, and photodiodes. The emission wavelength of LEDs are 660 nm and 800 nm. The 800 rim which is in the infrared region is very close to isobestic value for blood. The prototype sensor is mounted on the blood cell separator equipped with an antitwister mechanism. Each LED emits a specific wavelength of light …


The Accreditation Of Professional-Technician Occupations, Michael William Allgaier May 1990

The Accreditation Of Professional-Technician Occupations, Michael William Allgaier

Theses

This study investigates the relevance of different elements of accreditation as applied to professional and technical occupations. The impact of essential elements of typical accreditation programs on the outcome of the credentialing process is studied. The credentialing process is viewed in the context of how it affects the public safety, health and well being of society. The health, legal, engineering, and educational professions are analyzed to form a conventional professional base of comparison with the emerging professional-technical occupations in the nuclear industry, especially nondestructive examiners.

Nurses, attorneys, engineers, and teachers accreditation programs are analyzed for their strengths and areas for …


An Implementation Of Mht Algorithm For Adaptive Transform Coding Of Speech, Peter Battenschlag May 1990

An Implementation Of Mht Algorithm For Adaptive Transform Coding Of Speech, Peter Battenschlag

Theses

The Modified Hermite Transform (MHT), a suboptimum block transform scheme, is implemented on a TMS320C25 signal processing system with the objective of reducing the redundancy in speech signals and transmit a quantized vector representation at bitrates as less as 0.5 bits per sample.

The generation of the Hermite polynomials with a binomial and several first order IIR filter structures is presented focusing on the fact that no muliplications are required which simplifies the MHT algorithm considerably.

An assembler program performs forward and inverse transformation together with a vector quantization using adaptive bitallocation based on short-time statistics for the transform coefficients. …


Prestressed Concrete Columns Under Bending And Axial Load, Ajit Chiplunkar May 1990

Prestressed Concrete Columns Under Bending And Axial Load, Ajit Chiplunkar

Theses

A general analysis and design equation for slender and nonslender prestressed concrete columns subjected to uniaxial or biaxial moments combined with axial load is proposed. The proposed equation is an extension to the one developed by Hsu for reinforced concrete columns. The analytical results of the ultimate loads of eccentrically loaded slender prestressed columns are compared with the experimental results reported by Brown and Hall and Aroni respectively. The comparative study shows that the proposed equation of interaction diagram is in good agreement with the actual tests.

The ultimate loads of biaxially loaded short columns are also compared with the …


Teaching Mechanical Design Using The Axiomatic Approach, Lisa E. Hailey May 1990

Teaching Mechanical Design Using The Axiomatic Approach, Lisa E. Hailey

Theses

Many authors on the subject of design state that it cannot be taught, it must be learned through experience. This thesis offers a method in which design can be taught to senior mechanical engineering students. The axiomatic approach to design, authored by Dr. Nam P. Suh of the Massachusetts Institute of Technology, states that all good designs follow two axioms, the independence axiom and the information axiom. By teaching students to use these axioms, and the corollaries and theorems derived from the axioms, educators can teach students the basic concepts of good design.

To show how this approach can be …


Non-Parametric Dominant Point Detection Algorithms, Kuo-Wei Huang May 1990

Non-Parametric Dominant Point Detection Algorithms, Kuo-Wei Huang

Theses

Dominant point detection is one of the most important preprocessing steps for landmark-based shape recognition and point-based motion estimation. Two new methods for detecting dominant points are presented. Both methods do not require any input parameter and the dominant points obtained by these methods remain relatively the same even when the object curve is scaled or rotated.

In the first method, for each boundary point, a support region is assigned to the point based on its local properties. Each point is then smoothed by a Gaussian filter with a width proportional to its determined support region. A significance measure for …


Adhesion Effects In Micro Mechanisms, Dennis Alan Kalgren May 1990

Adhesion Effects In Micro Mechanisms, Dennis Alan Kalgren

Theses

Dielectric resonators (DR) are suitably shaped objects made of high dielectric constant materials like TiO2, BaO, ZnO, and accessory ingredients, which can function as electrical resonators covering a very wide frequency range upto 40GHz. The physical dimensions of dielectric resonators are in mm range. High dielectric constant material resonators seem to be ideally suited for microwave applications because of their miniature size, low loss, insensitivity to magnetic dc biasing fields, and ability to concentrate large RF magnetic fields in small volumes. However temperature stabilization of dielectric resonators is an important consideration as the center frequency is a function of temperature. …


Design Of Spatial Linkages For Dwell Function Generation, Donald F. Kelly May 1990

Design Of Spatial Linkages For Dwell Function Generation, Donald F. Kelly

Theses

Certain single-loop spatial linkages containing spherical pairs may be used as dwell function generators. Analysis and design of these linkages, however, may be too complex for the practicing engineer.

In this study a method is presented, where the set of link lengths representing a linkage are determined from a smaller set of design parameters. Graphical relationships are also found between the design parameters and functional requirements for dwell, such as output function amplitude and dwell range. These graphs may be used as design charts, and design becomes the calculation of link lengths from design parameters chosen to satisfy the functional …