Engineering Commons^™

Assessment Of Autonomic Regulation Of Heart Rate Variability, Shaw-Jyh Shin

Dissertations

Complex demodulation, accompanied by the techniques of interpolation, detrending and zero-phase-shift lowpass filtering were used to examine the effect of both divisions of the autonomic nervous system (sympathetic and parasympathetic) on heart rate by analyzing the heart rate variability signal from dogs under two different classical conditionings: CS+ and CS-, which cause different dynamic pattern changes in the autonomic nervous system to regulate the heart rate.

Unlike power spectral analysis, complex demodulation gives results in the time domain and shows the variation of amplitude and phase over time at a given frequency. The variation of phase indicates the frequency deviation …

Multiyear Drought Simulation With Periodic-Stochastic Hydrologic Processes, Lankeswara Hemal Wijayaratne

Dissertations

Previous studies on multiyear droughts are often limited to the analysis of historic annual flow series. A major problem in these studies is the unavailability of long historic flow records, on which to perform the analysis. To overcome this difficulty, the present study has used synthetically generated mean annual flow series to suppliment the historic flows. For the purpose of generating flows, a general methodology was developed to propose a mathematical model based on the harmonic and stochastic analyses of the historic flow series. The main objective was to derive a large population of multiyear drought events from the generated …

Sorption And Desorption Of Organic Compounds By Flyash, Kashinath Banerjee

Dissertations

A sorbent treatment process has been developed which uses flyash as sorbent in the treatment of highly toxic and hazardous chemicals; these include: Alcohols, Aldehydes, Ketones and Aromatics. Batch, as well as dynamic, studies were performed, in different phases, during the investigation. Single and multiple solute systems were examined separately. The samples were analyzed using a Flame Ionization Detector Gas Chromatograph.

The result of this study demonstrates that isolation/ immobilization of the organic pollutants is technologically feasible by adsorbing the contaminants onto flyash. The residual carbon content of the flyash plays a very significant role during the treatment process. The …

Design Of Bridge Inter-Connecting Token Ring & Token Bus Local Area Networks, Kasinath Anupindi

Theses

A Bridge interconnecting two Local Area Networks has been modelled. The two interconnected networks are the Token Ring and the Token Bus LANs. Concepts of Queueing theory have been employed in the design. Initially it is assumed that the buffer size at the Bridge is infinite. Further it is assumed that the arrival rate of the messages is Markovian and the service rate is General, Le it is an M/G/1 system. Expressions for the average waiting time at the Bridge and the size of the buffers is computed. Graphs for various parameters have been plotted. Based on these graphs the …

Data Flow Dependency Generator, Chin-Piao Chan

Theses

Data flow is a new approach to parallel computing. The concept is to enable the execution of an instruction whenever its operands become available. The only constraints in a data flow machine are the data flow dependencies between instructions.

In this thesis, a simulation package called the Data Flow Dependency Generator is developed. This package is designed to express the idea of data flow computations, the data flow dependencies and the use of multiprocessors.

Given a number of processors, a number of time units for each operation and a program, the Data Flow Dependency Generator finds the data dependencies between …

Utilization Of The Theory Of Constraints Approach For Improving A Manufacturing Enterprise Profitability : A Case Study, Yaron Chaut

Theses

The past two decades have been a difficult period for the U.S. as it lost its dominant position in one manufacturing industry after another to Japan. The American worker was initially blamed for this phenomenon - he was too expensive, was less productive, and produced lower quality products then the Japanese worker. The opening of factories in the U.S. managed by Japanese with American workers proved this claim to be wrong, as their products were competitive and often even better then the original Japanese products. It also indicated that the Japanese production planning and control methods are the primary reason …

A 3-D Tactile Sensor With Digital Output, Sin-Shou Cho

Theses

This thesis details the design of a new tactile sensor for general-purpose robot manipulators. Such manipulators, designed to be functionally equivalent to the human hand, will require sensor arrays that fulfill several requirements : (1) many sensor elements to minimize tactile imaging time, (2) close spacing of small sensing elements for fine spatial discrimination, (3) ability to be molded to a convex fingertip surface for taction on concave surfaces, (4) tolerance to over-scale forces without damage. In addition to the above, which are considered requirements, several other characteristics are desirable. Foremost is the ability to sense shear forces, which provide …

Expert Systems Approach For Means Of Egress Analysis, Dimitrios N. Dontas

Theses

The use of Expert Systems has grown dramatically during the 1980's. Developed as a branch of Artificial intelligence, knowledge based Expert Systems were at first of academic interest only. With successful application of knowledge based Expert Systems to medical and other diagnostic problems, industrial and commercial use of this technique is also increasing significantly. As of 1986, fifty percent of the Fortune 500 companies are embarked in their own Expert Systems research.

A variety of knowledge based Expert Systems has been developed for the Civil Engineering design and construction industries. The applications cover a wide range of subjects, including among …

A Methodology For Evaluating Prospective Investments In Flexible Automation, Werner A. Eikenbusch

Theses

The flexible automation of production systems (FA) provides the technology necessary for competitive success. However, the use of traditional budgeting methods has proved unsatisfactory when evaluating this type of investment, primarily because of the inadequate consideration being given to the resultant strategic benefits.

A methodology considered suitable for evaluating FA investments is proposed together with an illustrative application. To determine its industrial usefulness, manufacturing managers of North American and West German companies were surveyed both via interviews and via questionnaires. Their response confirms the merit of the procedure, despite the differences in competitive foci found between the American and the …

Effects Of Peripheral And Microwave-Core Heating On Survival In Hemorrhagic Shock In Rats, Ashraf Sabry El-Assuooty

Theses

In a model of rats resuscitated from hemorrhagic shock,where 11 of 12 animals were alive up to 4 hours after shock, there was an average drop of 10°C in core body temperature. Survival and morbidity was much impaired when the shocked animals were externally heated with an infrared lamp to maintain a core body temperature of 35°C. Since the increased intrashock mortality is possibly due to the circulatory changes induced by peripheral heating, an attempt was made to determine the effects of heating the animal at its core. Twelve rats were shocked in the same fashion, however the body core …

Stepping Motor Control And Position Monitoring, Pei-Kuan Feng

Theses

Stepping motors provide precise digital control of speed, without speed detector feedback. A stepping motor can produce a large torque for a relatively small displacement, without a shaft-position sensor or special compensation. This provides accurate control of motor position. This thesis describes the development of stepping motor torque characteristics and the different approaches stepping motor phase current waveform detection. It is shown that one of the most useful indicators of rotor position is the initial rate of current rise. The Hybrid, Permanent-magnet and Variable-reluctance step motors have been applied in the drive circuits. The open-loop control circuits are implemented to …

The Tapered Dielectric Rod-Conical Antenna, Nicholas I. Georghiades

Theses

The problem of the linearly tapered dielectric rod/conical antenna, excited by the HEI1 hybrid mode in a metallic circular waveguide , is rigorously studied. A theoretical model, and numerical investigation for the radiation characteristics of such an antenna are presented. The model is based on the combination of classical analysis of the Electromagnetic Fields within the dielectric rod, Local Mode Theory, and the Equivalence Principle for the determination of equivalent current distributions.

The far-zone radiation field is considered to be the summation of the fields produced by two radiative components in the dielectric rod/conical structure: The "aperture" of the uniform …

Micro Cad/Cam System Selection And Implementation, Christian Georg Haas

Theses

The rapid growth of the computer market in the last four decades causes difficulties in evaluating the various systems and configurations of this complex market.

This thesis focuses on graphics capable microcomputers in the computer aided design (CAD) and computer aided manufacturing (CAM) field. The thesis emphasizes the technical possibilities such a system offers in terms of hardware, software and applications. Each hardware and software component is detailed to give a new-comer the opportunity to update him or herself in this high technology field. Technical information, as well as installation and implementation are described. Also, provided are lists of several …

Microcomputer-Controlled Respiratory Rate Monitor, David John Hartmann

Theses

In order to measure the metabolic change in an animal due to the administration of anti-obesity drugs, an instrument was constructed which will allow the continuous sampling of twelve individual animals residing in enclosed chambers. The instrument is based on the principle of Indirect Calorimetry, which measures metabolic rate by sampling the inlet and outlet concentrations of respiratory gases (oxygen and carbon dioxide) of the chamber. The system is controlled by an IBM PC which will control six chambers or twelve chambers simultaneously.

The system assesses the metabolic rate of the animal by calculating the Respiratory Quotient (RQ) and the …

A Computer-Based Microwave Interferometer Instrumentation System As A Non-Invasive Cardiopulmonary Monitor, Chin-Yee Eric Ho

Theses

The system comprises a microwave interferometer as a computer-based non-invasive cardiopulmonary monitor. The microwave interferometer records the mechanical vibration of the chest wall. The objective is to determine whether the signals may have diagnostic value and to evaluate the instrument as a non-invasive and non-contacting cardiopulmonary monitor.

With the help of a computer it is possible to analyze the mechanical vibration of the chest wall produced by the heart and thereby detect, and possibly categorize, cardiac abnormalities. This system is able to process two channels, the first signal from microwave interferometer records chest wall vibrations and the second signal is …

Role Of Contact Stresses In Surface Fatigue And Wear, Chih-Chi Huang

Theses

This thesis is devoted to the role and analysis of stress distribution at the area of load and slide contact in the surface fatigue. The orthogonal shear stresses are critical stresses for surface fatigue in pure rolling contact. On sliding combination with rolling, the maximum shear stresses become to be the prime cause for surface fatigue because they move from subsurface toward the surface. The compressive residual stress induced during manufacturing could increase the resistance to surface fatigue. Sliding speed rarely affects the stress distribution and surface fatigue. From investigation of the stick-slip region in the contact area, sliding wear …

Failure Mechanisms Of Hermetically Sealed Solid Tantalum Capacitors, Syed R. Kazmi

Theses

This study has determined the failure mechanisms of solid tantalum capacitors and their causes. It was observed that high leakage current and electric shorts are the most prominant modes of failure. The experimental data has proved that humidity and high temperature are the factors which promote these kinds of failures. It is also stablished that change in electrical parameters due to exposure to harsh weather are reversible. Vacuum treatment to such capacitors helped in improving their electrical characteristics.

Investigation Of A Technology For Glass Shaping By The Use Of Abrasive Waterjet, Wu-Tzung Lee

Theses

This study investigates the effects of AWJ properties on the results of glass machining and examines the feasibility of contour glass cutting. The principal defects of AWJ glass cutting are identified. A practical technique to prevent defects and to improve the quality of the glass surface is presented. A computer package was developed to provide a computer-aided programming function, a control program transformation fuction, and a object image operation function. Throughout the programming function, robot control programs can be generated to improve cutting quality and cutting speed. The transformation function can be used to change the programming modes or the …

Apap: The Arithmetic Pipeline Analysis Package, Chang-Chieh Lin

Theses

This study is aimed at the development of an interactive PC-based package for simulating data flow within an arithmetic pipeline in multiprocessor systems. The user constructs the arithmetic pipeline, specifying the functionality of each segment, the intersegment connectivity and pipeline inputs and outputs. After defining reservation tables and data, analysis is performed with the results available in tabular, simple graphic and animated graphic forms.

APAP allows the user to design hardware and analyze its functionality with-out building the circuit, an economical alternative. Even when circuits are to be built, APAP allows the user to correct logic errors before implementation, leaving …

The Quantitative Determination Of Formaldehyde In Ambient Air (Analytical Method), Chitsan Lin

Theses

A procedure for coating in situ silica gel in prepacked cartridges with 2,4-dinitrophenylhvdrazine (DNPH) acidified with hydrochloric acid is described. The method was evaluated under practical field conditions in The Northern New Jersey-Staten Island Urban Air Toxics Project. The formaldehyde hydrazone formed is desorbed by acetonitrile and determined by high-performance liquid chromatography with UV det.ection. In this study, we have examined trap coaz)ng, trap efficiency, parallel ambient air and inaoor air sampLing, to find the best analysis method. Sampling traps aci:iifled .:ith hydrochloric acid perform better than those using percnicric acid or phosphoric acid. Trap sampling efficiency was significantly affected …

An Analysis Of The Second-Order, Type-One Hilbert Phase-Locked Loop, Inn-Shian Lin

Theses

In this thesis, a second-order, type-one PLL ( Phase- Lock, Loop ) in which the usual lead-lag loop filter is paralleled with a Hilbert Transformer (the whole system is called HPLL) is analyzed. A motivation for the study was that earlier researchers have found improved performance if Ilse lead-lag network is paralleled by a differentiator, result mg in the so called ERPIM (Extended-Range Phase-Locked Demodulator). For the purpose of com-parison with earlier experimental and analytical results on the PLL and the ERPLD, the numerical results in this thesis ale based on the parameters of Acampora and Newton.

The basic characteristics …

Simulation Study Of The Multi-H Continuous Phase Modulation, Min-Ling Lin

Theses

Of particular interest in satellite communications are modulation techniques that have a relatively constant envelope and are power and bandwidth efficient. Attempts have been made to satisfy these requirements by using phase and frequency modulation formats. Recently, one approach has been researched which combines the modulation and encoding functions, which is referred to as multi-h continuous phase modulation. Simultaneously good power and bandwidth efficiencies can be achieved at the expense of increased complexity.

This report examines the performance of multi-h continuous phase modulation by a simulation. A multi-h phase coded modulation is generated, passed through the AWGN transmission channel. The …

Gallium Arsenide Standard Cell Cad Database For Digital Design, Nanchou Liu

Theses

This thesis develops a selected design database of gallium arsenide logic cells for automated design. Uniformly applied 1 um gate length physical layout rules are used for the design database with a standard cell design methodology.

Schottky Diode FET Logic (SDFL) technology with double level metallization was selected following a consideration of alternative gallium arsenide MESFET logic types. The SDFL approach is judged to provide improved noise margin, production yield, density, and lower power dissipation.

A cell library with 60 um cell height has been implemented with double entry for each cell input/output. Each cel1 has been simulated with SPICE …

Contrast Sensitivity Measurement Via Evoked Potential, Ken-Gen Lu

Theses

This work is concerned with the use of the visual Evoked Response (VER) to determine Contrast Sensitivity in humans. For this purpose, a system has been developed where signals, obtained from scalp electrodes, and stimulated by visual grating patterns, are recorded digitized and processed on a personal computer (IBM compatible). Processing includes signal averaging and digital filtering. The system provides storage, retrieval and graphic representation of data as well as the capability to transfer data to other computer systems. Data processing includes parameter estimation of suitable signal models, which provide effective data compression of the signal into a finite set …

Asics Application On Voice Processing Interface Design- Qegg Multiplier, Gwo-Jen Luar

Theses

Application Specific Integrated Circuits (ASIC) is a high density VLSI design that including the lower cost, higher performance, small size, and increased reliability. The ASIC, XILINX's LCA is applied on the signal processing ahead of computer I/O interface, specially for the quantitative Electroglottograph. This thesis covers the logic design, simulation test, realization, and stand alone test.

Computer Aided Synthesis Of A Four-Bar Linkage To Generate A Symmetrical Coupler Curve, Shailendra R. Pachalag

Theses

The purpose of this study is to develop a new analytical technique for the synthesis of four-bar mechanisms to generate symmetrical curves with a coupler point passing through 8 points. The geometric expressions involved in kinematic synthesis often tend to offer difficulties such as negative radicals, alternative choices and repetitions. Here a solution procedure has been developed which avoids these difficulties. This solution procedure includes a development of a computer algorithm that should synthesize a crank-rocker type linkage for any given input crank length. This algorithm dismisses all solutions involving negative radicals and lists magnitudes of members so that those …

Design Criteria Of Coherent Optical Fiber Communication System, Rajesh N. Patel

Theses

Design criteria of coherent optical fiber communication system were discussed and investigated. First, the different types of optical fibers (waveguides) were discussed. Then the laser sources, photo-detectors, transmitter & receiver circuits were discussed in detail.

Design criteria of conventional intensity modulated (direct detection) optical fiber communication system were discussed. Then, the design criteria and estimation of number of photons for different modulation schemes for coherent optical fiber communication system were analyzed.

Coherent optical fiber communication system's advantages and drawbacks were discussed in detail. Improvement in receiver sensitivity of coherent detection compare with conventional direct detection was investigated. Finally, some receiver …

An Improved Method Of Gas Chromatographic Determination Of Trace Organic Vapors In Ambient Air Collected In Canisters, Yong-Jin Shen

Theses

An improved method for analysis and quantitation of volatile organic compounds in ambient air has been developed. Samples are collected in evacuated SUMMA polished stainless steel canisters using a sampling flow apparatus with a critical orifice as flowrate controller. Analysis of VOCs in the collected air is carried out by cryogenically concentrating the sample, then thermally transfering it onto the head of a capillary column in a gas chromatograph. The column effluent is measured by a parallel flame ionization detector (FID), and electron capture detector (ECD). The problems associating with quantitative transfer of the sample to the initial cryofocusing loop …

Recycled Plastics As Fillers In Polymer Cement Concrete Composites, Shian-Jong Liu

Theses

How to handle the plastic waste is a big task for the modern society in environmental protection. People already focus on it, especially in PET soft drink bottles. Although PET bottle can be reclaimed, its usages are restricted due to the limitation in color and difficulty in purification.

On the other side, concrete is the most common material for human beings to used [sic] in construction. Concrete has good compressive strength, but poor [sic] in flexural and tensile strengths, which limits its applications. So, scientists try to improve its properties by adding the polymer into the conventional concrete, to enhance …

Sorptive And Geotechnical Characteristics Of Kaolinite, Chi-Yuan Shih

Theses

The sorption/desorption behavior of phenol and chlorobenzene as well as their influence on geotechnical characteristics of kaolinite were studied. The results reveal that the sorption process follows closely with the Freundlich adsorption isotherm whereas the sorption/desorption ratio depends upon the characteristics of organic compounds.

A series of geotechnical properties tests was also undertaken after achieving equilibrium at different concentrations of organic compounds. It was found that the parameters such as liquid limit, plastic limit, optimum moisture content, and dry density increase with an increasing-concentration of organic compounds.

The relationship between the geotechnical, properties and sorption behavior of soils provides the …