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Taiwan's Economic Development, Liwen Chang Aug 1990

Taiwan's Economic Development, Liwen Chang

Theses

Development, by definition, brings new resources into a society that allow for a higher standard of living. Many developing nations which changed from a traditional survival type society to a self-supporting society experienced a high rate of economic growth after the World War II. No matter what route these countries or regions took to success, in the process of development they all faced similar international trade and balance of payments problems.

This paper presents a case study of Taiwan as a developing country's model. Taiwan certainly qualifies as a successful example of development. Although there is really no complete normative …


Hardware Algorithms For Computing Transcendental Functions, Xin-Pei Gong Aug 1990

Hardware Algorithms For Computing Transcendental Functions, Xin-Pei Gong

Theses

The COordinate Rotation Digital Computer(CORDIC) is a special-purpose digital computer for real-time airborne computation. In this computer, a unique computing technique is employed which is especially suitable for solving the trigonometric relationships. A new computing technique based on the CORDIC algorithm is developed to reduce the number of iterations by one half for each input angle. This improvement is accomplished. by scanning multiple bits of the input angle(in our case, two) at a time. The CORDIC equations are rewritten accordingly and a hardware implementation structure is also presented. The results of the software simulation of the new algorithm are as …


Decomposing Non-Product Form Queuing Lattices Through Genetic Algorithm, Wei Han Aug 1990

Decomposing Non-Product Form Queuing Lattices Through Genetic Algorithm, Wei Han

Theses

In this paper, a Genetic Algorithm technique is adapted to decompose the state transition lattice of a class of non-product form queueing models. Genetic Algorithms are search algorithms based upon the mechanics of natural genetics. They combine a survival-of-the-fittest among string structures with a structured, yet randomized, information exchange to form a search algorithm with some of the innovative flair of human search. While randomized, genetic algorithms are no simple random walk. They efficiently exploit historical information to speculate on new search points with improved performance. Here genetic algorithms is applied to a non-product queueing lattices optimization problem. Only the …


Scatterer Number Density Estimation For Tissue Characterization In Ultrasound Imaging, Hui Zhu Aug 1990

Scatterer Number Density Estimation For Tissue Characterization In Ultrasound Imaging, Hui Zhu

Theses

Ultrasound RF signal, backscattered from an inhomogeneous parenchymal tissue has the character of a random signal. It is the random fluctuating nature of this signal that is responsible for the speckle pattern observed in the images. These random signals, nevertheless, bear information related to the random scattering structure of the medium. Statistical moments of the signal can serve as feature parameters that are related to mean scatterer spacing in the random structure. However, such a feature is biased because the statistical nature of the RF signal depends, not only on the random tissue scattering structure, but also on the resolution …


Measurement Of Thermal Conductivities Of Polymer Films With The Tc-1000 Thermal Comparator, Dong Ming Li Aug 1990

Measurement Of Thermal Conductivities Of Polymer Films With The Tc-1000 Thermal Comparator, Dong Ming Li

Theses

The single-probe, direct reading thermal comparator has been used extensively to measure the thermal conductivity of bulk solids, liquids, and gases. With the use of an analytical heat flow model based on the work of Dryden1 and the work of Carslaw and Jeager2, the comparator can also be used to obtain an in-situ measurement of the thermal conductivity of a film while attached to a substrate. The purpose of this paper is to test this model by measuring the thermal conductivities of commercially available polymer films (DuPont Kapton and Teflon). The values obtained with the comparator were found to be …


Transputer-Based Robot Controller, Wei-Chieh Chang Aug 1990

Transputer-Based Robot Controller, Wei-Chieh Chang

Theses

A cost-effective architecture for the control of robot manipulators based on functional decomposition of the equations of motion is described. The Lagrange-Euler( LE) and the Newton-Euler( NE) formulations are used for decomposition. According to real-time control criterion, the LE equations are not suitable for implementation using currently available hardware because the required number of computations is too high, even after taking the inherent parallelism into account. However, the recursive nature of the Newton-Euler equations of motion lend themselves to being decomposed to terms used to generate the recursive forward and backward formulations. A special architecture implemented on a network of …


Prediction Of Screener-Induced Moire In Digital Halftone Pattern Generation, Richard Comeau Aug 1990

Prediction Of Screener-Induced Moire In Digital Halftone Pattern Generation, Richard Comeau

Theses

In the graphic arts, objectionable moire patterns are often observed on films or printed products due to the interaction of various periodic structures of halftone images. A particular type of moire pattern that results from digital halftoning at arbitrary angles and frequencies using a virtual screen function has been studied. A computer program was developed that produces uniform digital halftone patterns using a virtual screen approach and that calculates the corresponding amplitude spectra. It was found that aliasing due to the sampling of the virtual screen causes low frequency components in the amplitude spectrum. Moire patterns with fundamental vector frequencies …


Investigation Of An In-Situ Method For Determining The Modulation Transfer Function And Its Applications In A Microlithographic Wafer Stepper, Steven D. Carlson Aug 1990

Investigation Of An In-Situ Method For Determining The Modulation Transfer Function And Its Applications In A Microlithographic Wafer Stepper, Steven D. Carlson

Theses

Research into characterization of wafer stepper systems has been done primarily by analyzing a series of wafer exposures. This method does not allow for easy separation of the effects of the exposure system and the resist processing system. In addition, determination of the transfer characteristics of projection lithographic lenses is typically done before the lens system is installed into the wafer stepper system. A method is presented which allows for the in-situ determination of the modulation transfer function. This method separates the processing effects from those of the exposure system. Scattered light from a polys il icon edge is shown …


Improved Techniques For Bispectral Reconstruction Of Signals, Gopalakrishnan Sundaramoorthy Aug 1990

Improved Techniques For Bispectral Reconstruction Of Signals, Gopalakrishnan Sundaramoorthy

Theses

Higher order cumulants and spectra have found a variety of uses in many areas of digital signal processing. The third order spectrum, or bispectrum, is of specific interest to researchers because of some of its properties. The Bispectrum is defined as the fourier transform of the third order cumulant se quence for stochastic processes, and as a triple product of fourier transforms for deterministic signals. In the past, bispectral analysis has been used in applications such as identification of linear filters, quadratic phase coupling problems and detection of deviations from normality. This work is aimed at developing techniques for reconstructing …


A Study Of Design Parameters Of A Road Racing Endurance Car, Donald N. Kords Aug 1990

A Study Of Design Parameters Of A Road Racing Endurance Car, Donald N. Kords

Theses

Analytical methods are presented to assess design parameters and aerodynamic effects on a road racing endurance car design. A six degree of freedom model of the vehicle dynamics was used to determine the design equations and objectives. Some of the more important parameters investigated were vehicle mass and inertia, aerodynamic drag and down force, rolling resistance, center of gravity, cornering capacity and braking performance. The effects of these parameters on the vehicle acceleration, velocity, and lap times were investigated analytically and verified by data obtained by on-board instrumentation. Given nearly identical engine performance from car to car, the aerodynamic parameters, …


A New Image, Scott E. Rummler Jul 1990

A New Image, Scott E. Rummler

Theses

This thesis paper is about the development and completion of a series of oil paintings. Some of the images were exhibited at the Bevier Gallery at the Rochester Institute of Technology this Spring, in partial completion of the requirements for the Master of Fine Arts degree. This paper will complete the requirements. The paper will give a chronology of the development of the paintings, beginning with the ideas that preceded the works, and leading through the various stages of their completion. A final section will consist of an artist's statement and will relate my work to some of the dilemmas …


Small Disturbance Stability As Affected By Excitation Controls, Alfredo Flores Jun 1990

Small Disturbance Stability As Affected By Excitation Controls, Alfredo Flores

Theses

The effect of excitation control systems on the power system's small disturbance stability limits has been investigated in this thesis. Three excitation control schemes namely the proportional, fast?acting and the modified fast?acting have been studied.

The stability results were predicted directly in terms of the AVR gain controlling parameters following one?dimensional and two?dimensional frequency domain separation technique. The necessary algorithms and computer simulation programs have been developed.

In case of a modified fast?acting excitation control with three unknown variables, a procedure has been proposed to obtain the stability results by extending the two?dimensional frequency domain separation technique.


Improving Solids Conveying In Plasticating Extruders : An Investigation Into Manufacturing Processes And Manufacturing Systems For Profiled Thermoplastic Pellets, Oommen Cherian Jun 1990

Improving Solids Conveying In Plasticating Extruders : An Investigation Into Manufacturing Processes And Manufacturing Systems For Profiled Thermoplastic Pellets, Oommen Cherian

Theses

The objective of the thesis is the manufacture of thermoplastic bilobal and trilobal profiled pellets for the determination of the interparticulate co-efficient of friction exhibited by solid beds of such pellets. The enhancement of the interparticulate coefficient of friction is expected to lead to ameliorated solids conveying rates in plasticating extruders.

Predicting the product shape from a profile die is very difficult due to the elastic memory of plastics and the complex boundary conditions. Consequently the cost involved in experimenting with different profile dies is high. Therefore a standard die with several die inserts of varying cross-sections were used to …


Correlation Of Finite Element And Experimental Eigenvectors, Derek J. Krebs Jun 1990

Correlation Of Finite Element And Experimental Eigenvectors, Derek J. Krebs

Theses

A technique for correlating a complex structure's finite element eigenvectors with its respective experimental eigenvectors is presented. The technique provides a quantitative comparison of the finite element and experimental eigenvectors by using a reduced finite element mass matrix in a "cross" orthogonality check. Comparisons of two case studies are presented: a thin plate with motion in the Z-direction only and a 3-dimensional table structure with motion in three principal coordinate directions . Along with the orthogonality check, the difference in the eigenvectors is computed and shown graphically. The orthogonality check between the finite element and experimental eigenvectors can serve as …


A Comparative Study Of Edge Detection Techniques, Jaskaran Singh Dhaliwal May 1990

A Comparative Study Of Edge Detection Techniques, Jaskaran Singh Dhaliwal

Theses

The problem of detecting edges in gray level digital images is considered. A literature survey of the existing methods is presented. Based on the survey, two methods that are well accepted by a majority of investigators are identified. The methods selected are: 1) Laplacian of Gaussian (LoG) operator, and 2) An optimal detector based on maxima in gradient magnitude of a Gaussian-smoothed image. The latter has been proposed by Canny[], and will be referred as Canny's method. The purpose of the thesis is to compare the performance of these popular methods. In order to increase the scope of such comparison, …


An Artificial Neural Network For Redundant Robot Inverse Kinematics Computation, Wibawa Utama May 1990

An Artificial Neural Network For Redundant Robot Inverse Kinematics Computation, Wibawa Utama

Theses

A redundant manipulator can be defined as a manipulator that has more degrees of freedom than necessary to determine the position and orientation of the end effector. Such a manipulator has dexterity, flexibility, and the ability to maneuver in presence of obstacles. One important and necessary step in utilizing a redundant robot is to relate the joint coordinates of the manipulator with the position and orientation of the end-effector. This specification is termed as the direct kinematics problem and can be written as x = f(q)
where x is a vector representing the position and orientation of the end-effector, q …


Statistical Process Control For High Precision Deep Drawn Sheet Metal Parts, Sunil S. Shah May 1990

Statistical Process Control For High Precision Deep Drawn Sheet Metal Parts, Sunil S. Shah

Theses

In today's world, industrial expertise has come to be judged in terms of the quality of the product. Good quality has become the ultimate aim in a manufacturing environment, which leads to many innovations for ease in the inspection of parts. In considering a metal working company like Hudson Tool & Die Company, a study of the various operations and the application of Statistical Process Control to the forming operations is performed using STORM software. Important characteristics have been carefully studied with regards to metal forming like uniform metal thickness, radius of the bend, depth of the drawing operation. In-depth …


Multiprocessor System Design Tutor : Expert System Approach, Rakesh Kamdar May 1990

Multiprocessor System Design Tutor : Expert System Approach, Rakesh Kamdar

Theses

To increase computational bandwidth and system resilience, integration of several microprocessors in a single system becomes necessary. The overall throughput and efficiency of such a system is directly dependent on the hardware and software interconnection supported by the basic microprocessor chip. Sometimes it becomes difficult to put together all the information for design criteria and all the design related formulas.

The approach made here is to continuously update the hardware and software information in the database related to a given microprocessor. This information can be accessed at any time for efficient design solution. Intel 80386 and Motorola 68020 microprocessors are …


A Study Of The Effects Of Weighting Matrices In Power System State Estimation, Yanshi Wang May 1990

A Study Of The Effects Of Weighting Matrices In Power System State Estimation, Yanshi Wang

Theses

The effects of weighting matrices that may be used in the Weighted Least Squares (WLS) method when applied to the problem of Power System State Estimation (PSSE) are studied. These weighting matrices include the one usually used in the literature and the one used in the utility PSSE programs

The performances of these weighting matrices are compared using the Monte Carlo simulation technique.

To test the performances of the weighting matrices, a PSSE program is developed, different performance indices for state comparison are defined, and many cases are studied.

Results show that the weighting matrix usually used in literature, 1/σ², …


Trends Of Metals (Pb, Zn, Cd, Cr, Mn, Fe, Hg And Ni) Concentration In The New Jersey Air Environment, Shobha R. Boddu May 1990

Trends Of Metals (Pb, Zn, Cd, Cr, Mn, Fe, Hg And Ni) Concentration In The New Jersey Air Environment, Shobha R. Boddu

Theses

The atmospheric concentrations and relative trends of ten trace elements (Co, Cd, Fe, Hg, Pb, Ni, Zn, Cu, Cr and Mn) were studied at Elizabeth and Carteret, New Jersey from July 1987 to September 1989. The specific sites are Industrial and Residential Interface areas. The analytical procedure involved collection of the airborne particulates on a quartz microfiber filter using a high volume sampler. The samples were digested and then analyzed using the atomic absorption spectrometer. Elizabeth usually showed lower values for the metals than Carteret. Average concentrations (ng/m3) for the respective metals over the entire project are: Metal: Co Cd …


Biodegradation Of Polymers And Isolation And Crude Characterization Of Proteins From These Studies, Sunil S. Godbole May 1990

Biodegradation Of Polymers And Isolation And Crude Characterization Of Proteins From These Studies, Sunil S. Godbole

Theses

The performance of immobilized and free microorganisms in the biodegradation of polymers was investigated using a recirculation flow reactor and an air-sparged reactor respectively. The bio-oxidation ability of these microbes towards polyamide emulsion was studied.

Extracellular protein cuts isolated were checked for oxidative activity in a microassay reactor. These fractions were compared from various biodegradation studies.

Microassay tests and monitoring of the oxygen consumption in recirculation flow confirmed substrate dependent oxygen consumption, polyamide being provided as the sole carbon source. Increases in extracellular protein buildup were a positive indication of biodegradation.

The protein cut greater than 500,000 daltons was found …


Thermal Desorption Of Contaminated Soils, Chengdi Dong May 1990

Thermal Desorption Of Contaminated Soils, Chengdi Dong

Theses

The objectives of this research are of twofold, namely, to investigate the desorption behaviors of hazardous constituents evolved from several types of contaminated soils, and to evaluate the in-situ thermal treatment of organic chemical contaminated soil.

Two clay soil minerals and a silty sand with five organic compounds, dichlorophenol, trichlorophenol, pentachlorophenol, trichloroethylene, and tetrachloroethylene (TCE) were used in this study. The desorption behaviors were evaluated by thermogravimetric analyzer (TGA) and a simulator of in situ desorption by heating probes. The results of TGA analysis revealed that a completely removal of organic contaminants can be achieved in a moderate temperature. They …


Quality Assurance Studies For Collection Of Whole Air Samples In Stainless Steel Canisters, For Volatile Organic Compound Determinations, Weifang Ji May 1990

Quality Assurance Studies For Collection Of Whole Air Samples In Stainless Steel Canisters, For Volatile Organic Compound Determinations, Weifang Ji

Theses

Internally polished stainless steel canisters are being used in many laboratories to collect whole air samples for VOC analysis. The replacement of adsorbents for collection and concentration of VOC by canister collection, with in-laboratory cryogenic concentration, may solve some problems associated with adsorbents, such as artifact generation and breakthrough. However, the canisters can be a source of new problems, ranging from wall adsorption to memory effects.

In this work, four major contamination sources in the whole air sampling and analyzing system have been identified. They are the canister internal adsorption, the whole system transfer line, the air pump and the …


Chemical Degradation Of Pcp And Polychlorophenols, Kon-Tsu Kin May 1990

Chemical Degradation Of Pcp And Polychlorophenols, Kon-Tsu Kin

Theses

There are generally two ways of removing PCP and polychlorophenols from the environment: biodegradation and photodecomposition. However, no convenient way has yet been available to destroy PCP wastes which exist in a concentrated form which may result from some cases of emergency spills. In this thesis, a chemical oxidation procedure is proposed for the destruction of PCP and polychlorophenols.

In a water medium and in the presence of base and oxidant, the PCP and model polychlorophenols destruction percentage obtained is higher than 99.8%. Sodium hydroxide (NaOH) and calcium hydroxide (Ca(OH)2) are utilized as the bases, and sodium hypochlorite …


Image Data Compression With Neural Networks, Jianjun Li May 1990

Image Data Compression With Neural Networks, Jianjun Li

Theses

Three efficient image coding schemes, based orb neural networks, have been developed in this thesis: (1) Neural network vector quantization (NNVQ). The main advantage of this new technology is that it can accomplish the complex encoding process much faster than the previous algorithms. Its properties are studied and demonstrated by simulations. (2) A adaptive NNVQ for image sequence coding. Simulation experiments have been carried out with 4 x 4 blocks of pixels from an image sequence consisting of 40 frames. At 0.67 bits/pixel, this scheme achieves good image quality suitable for videoconferencing systems; (3) Neural network prediction. This new prediction …


Cascading Of Arithematic Coding Method With The Lzw Algorithm, Venkat R. Maram, Nageshwar R. Kadakuntla May 1990

Cascading Of Arithematic Coding Method With The Lzw Algorithm, Venkat R. Maram, Nageshwar R. Kadakuntla

Theses

Two known compression algorithms appropriate for communication are the LZW algorithm and the Arithmetic Coding method. Both algorithms are adaptive and require no extra communication from the encoder to the decoder. We present a scheme to cascade these algorithms into an adaptive algorithm which achieves higher compression ratio and is appropriate for communication.


Trellis Coded Tamed Frequency Modulation In Rayleigh Fading Channels, Kiran R. Patel May 1990

Trellis Coded Tamed Frequency Modulation In Rayleigh Fading Channels, Kiran R. Patel

Theses

It is usually difficult to reduce the effects of channel impairements on transmitted information. A fading channel is one such media in which digital communications system operates. A signal is subject to distortion in amplitude and phase when propagating towards the receiver. This puts constraint in required SNR at the receiver, for given performance. Various modulation/coding and demodulation/decoding techniques are employed to lessen the effects of fading. Bit error rate is a performance parameter that sets the criteria for signal design, system architecture and performance.

Here, a slow Rayleigh fading channel with three propagation paths possesing a scattering function of …


Selection Of Master Degrees Of Freedom In Model Reduction Techniques, Yixing Qi May 1990

Selection Of Master Degrees Of Freedom In Model Reduction Techniques, Yixing Qi

Theses

Based on the model reduction technique called SEREP (System Equivalent Reduction Expansion Process), systematic ways to select the master degrees of freedom (the degrees of freedom kept in the reduced model) are developed and their usefulness is demonstrated by the examples. The following two criteria are ' developed for two specific objectives.

When we need to identify the response of the full model from the response of the reduced model (usually obtained from the experiments,) we hope to reduce the estimation error between the estimated response and the actual one. We also hope to keep the points which will have …


Modification Of Turret For Enhancement Of Internal Turning Operations On A Cnc Lathe, Talla Rajasekhar May 1990

Modification Of Turret For Enhancement Of Internal Turning Operations On A Cnc Lathe, Talla Rajasekhar

Theses

Towards the modification of the CNC turret a complete set of tool holders have been designed. They have been manufactured and installed according to the specifications. A detailed study of MARK CENTURY 2000 controller and PartMaster is presented. Additionally a component has been designed to be machined on the CNC lathe utilizing the MC2000 part programming capabilities. The part program of the machine component has been developed utilizing various phases of MC2000's Partmaster software. The generated part program has been executed on the CNC lathe.


A Study Of Signal Cancellation Effects In Adaptive Arrays, Cheng-Der Sun May 1990

A Study Of Signal Cancellation Effects In Adaptive Arrays, Cheng-Der Sun

Theses

An adaptive array can automatically place pattern nulls in directions from which undesired signals (interference, jamming, or clutter, etc.) arrive and can also provide gain for a desired signal. The purpose of this study was to study the effects of the adaptive array on the desired signal while suppressing the undesired signal.

This was done by studying the transfer characteristics of the adaptive array between its input and output. In this study, C.W. jammers along with the desired signal were considered and input and output relationship of the adaptive array were determined. Several basic types of adaptive arrays were studied …