Engineering Commons^™

Seizure And Wear Testing Methodology, I-Tsung Shih

Theses

In this work the seizure as an adhesive wear has been discussed and analyzed The diffusion hypotheses is accepted as the seizure mechanism. It was determined that the surface of machine components, material properties, and contact stresses in sliding and loading zone are responsible for the wear.

A computer controlled wear testing methodology has been developed and a wear testing machine has been designed and assembled. The tests for the selected gray cast non and alloy steel specimens with different surface treatment were performed on the designed wear testing machine.

The test results showed that the selected materials with additional …

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 …

Wastewater Treatment : Phenol Extraction By Liquid Membrane, Jan-Ming Hou

Theses

Two models for the extraction of phenol by means of liquid surfactant membranes is presented in which external mass transfer around w/o emulsion drop, phase and chemical equilibria are taken into account.

The nonlinear coupled P.D.E.'s is solved under assumptions to get a close-formed analytical approximate solution. The experimental results on the batch extraction of phenol are found to be satisfactory simulated by one of the proposed models provided that phenol concentration is higher than 0.01N. The model requires no adjustable parameter thus it can predict the extraction behavior without doing experiments.

Investigation Of Different Cmos Dram Sense Amplifier Configurations In Vlsi, Bihju Chiu

Theses

Sense amplifiers are particularly difficult circuits to design. In this work, only CMOS sense amplifiers are considered. There are typically two configurations of CMOS sense amplifiers: the cross-connected flip flop configuration and the current-mirror configuration. They are widely used nowadays with various modifications. These improved configurations are simulated and optimized with SPICE package, and their relative performances are also compared in this thesis.

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 …

System Performance Criteria In Cdma Networks Using Gold Codes, Yong H. Kim

Theses

First, we have presented the autocorrelation and crosscorrelation properties for periodic and aperiodic binary sequences. The generation of binary sequences using shift registers with feedback was reviewed. We have also included correlation properties for the Gold codes.

Next, we discussed Gold code generation for the balanced and unbalanced Gold codes.

Thirdly, we investigated the number of simultaneous users in a CDMA system using Gold codes for the worst case and the average case of mutual interference.

Finally, we simulated the probability of interference exceeding a threshold value, and the average crosscorrelation value caused by interference in a CDMA network which …

Modeling And Simulation Of Robot Arms With Flexible Links, John G. Danis

Theses

The design of lightweight robot arms introduces a degree of flexiblity in the individual links which renders the arm difficult to control. Solution of the control problem requires accurate and detailed mathematical models of the arm dynamics. A comprehensive survey of the current literature in this area has shown that although many such models exist, there is a great diversity in their structure, function, and applicability. The different objectives and techniques of model development which lead to this diversity are examined and summarized in this thesis. Bases for classification of the mathematical models and techniques of development are established, and …

An Investigation Of Electrical And Optical Properties Of Reactively Sputtered Silicon Nitride And Amorphous Hydrogenated Silicon Thin Films, Tae Hoon Kim

Theses

Thin films of silicon nitride and amorphous hydrogenated silicon were prepared by radio frequency reactive sputter deposition and their properties optimized for their use as low temperature passivation coatings for optoelectronic devices. The effect of various sputter deposition parameters on the conduction and optical properties were studied. Infrared spectrophotometry and ellipsometry were used to determined the optical properties of the films whereas the electrical properties were determined from current-voltage measurements of MIS capacitors.

Typical parameters of a sputter deposition run for the best Si₃N₄ films were: base pressure, 1-2x10^-6 torr; sputtering pressure, 5 mtorr; nitrogen partial …

Agitation Requirements For Complete Dispersion Of Emulsions, Dun-Huang Tsai

Theses

An investigation on the minimum agitation speed required to achieve complete dispersion in liquid-liquid systems has been carried out. A model based on the momentum balance for a droplet and on Kolmogoroff's theory of isotropic turbulence was used for the prediction of the role of the most important variables on the minimum agitation speed. The equation so derived can be expressed in terms of a number of non- dimensional groups (such as Re, Ar, and Su). For geometrically similar systems the equation contains only one adjustable parameter ( to be determined experimentally) in the form of the proportionality constant correlating …

Bead Design For Biodegradation Of 2-Chlorophenol Using Microorganisms Entrapped In Alginate Gel, Fayaz Lakhwala

Theses

The performance of immobilized cell reactors varies with a number of parameters, one of which is proper bead design. A mixed microbial population from a waste water treatment plant was immobilized in calcium alginate gel. The viability of these organisms was studied in a microassay reactor by varying parameters such as concentration of calcium chloride, concentration of sodium alginate, temperature of operation, biomass concentration within the beads and concentration of a model compound (2-chlorophenol). The effect of storage on viability over a period of three months was also investigated. It was found possible to have access to active biomass by …

Biosynthesis Of Amine Oxides Using Calcium-Alginate Immobilized Hog Liver Microsomes : An Evaluation Of Process And Reactor Design, Ioannis I. Valvis

Theses

An evaluation of the biocatalytic ability and the potential utilization of Calcium-alginate immobilized hepatic microsomes (beads) for the biosynthesis of amine oxides has been performed, To accomplish this task, the following three areas Were investigated: immobilization, catalytic biooxidation ability, and reactor configurations.

Immobilization was found to result in higher yields over free microsomes at the expense of higher cofactor requirements. Refrigerated drying of immobilized micro-somes appears to be a better storage technique than wet storage in buffer. Smaller beads resulted in higher rates than larger beads, but size did not affect the overall yield.

Chlorpromazine (CPZ), diphenylamine (DPA) and 4-hydroxy-2,2,6,6-tetramethylpiperidine …

Use Of Recirculation Reactor To Study Biodegradation Of 2-Chlorophenol, Kai-Chung Yang

Theses

The performance of immobilized cells in the treatment of hazardous waste was investigated using a recirculation flow reactor run in a batch mode. A mixed microbial population from a municipal wastewater treatment plant was immobilized in calcium alginate gel. The bio-oxidation ability of these microbes towards a model toxin (2-chlorophenol) was studied. The process parameters studied were as follows:

1. Flow rate of the recycle stream;
2. Biomass loading;
3. Spiking concentration of 2-chlorophenol;
4. Use of buffered vs. non-buffered defined medium.

Dissolved oxygen concentration was monitored using a flow Clark-type dissolved oxygen probe. Oxygen consumption was correlated with the biodegradation of 2-chlorophenol. Physical …

Investigation Of Forces In The Course Of The Water Jet--Work Piece Interaction, Hung-Yuan Li

Theses

This study is concerned with the dynamic of the interaction between the water jet and the work-piece. The piezoelectric transducer was used to construct an experimental setup. The simultaneous use of the constructed setup and strain gage enables us to validate the experimental procedure. The forces in the impingment zone were measured at different operational conditions. Totally about 400 different combinations of these conditions were tested. It was found that the force is mainly determined by the diameter of the sapphire. The effects of the abrasive size , abrasive flow rate, the diameter of the carbide tube, and the stand-off …

A Dynamic Model Of A Fill-And-Draw Reactor And Its Implications For Hazardous Waste Treatment, Shing-Hwa Chang

Theses

A dynamic model of a fill-and-draw reactor has been developed, which includes a number of operational parameters such as the draw-down volume, the fraction of total cycle time devoted to fill, reaction, and draw, and the concentration of the toxic substance in the feed to the reactor. The model has been solved numerically for two cases, one assuming Monod kinetics, and one considering substrate inhibition (Andrews kinetics).

The conversions achieved with this type of reactor have been compared to that of a conventional activated sludge (CSTR) design. These results indicate that for most practical settings of the operating parameters, the …

Synergistic Fillers In Polymer Concrete : New Composites, Syed Hassan Javed

Theses

The objective of this study was to examine the effects of synergistic fillers on underwater construction, burning and mechanical properties of polymer portland cement concrete(PPCC).

Fine grains of hydrous calcium sulfate, Trihydrated alumina, Calcium carbonate and fibrous unhydrous calcium sulfate were examined in PPCC. It has been observed that these synergistic filler improves the mechanical property (stress) and reduce the average time of burning of PPCC. With fixed quantity of polymer, the deterioration of PPCC in water increases by replacing the sand with above stated fillers.

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 …

Fetal Phonocardiography, Jeng-Kwan Lin

Theses

A reliable non-invasive tracking of the fetal heart rate from the maternal abdominal surface could be of significant diagnostic importance in the monitoring of pregnancies, not only for fetal heart rate assessment, but also for the observation of congenital cardiac malformations and transient difficulties during labor. Further, the fetal heart rate recording may be used to assess fetal heart rate variability in the antepartum period of gestation when it is not possible to obtain a fetal scalp lead electrocardiogram.

There are several methods being used to detect the fetal heart rate. Phonocardiography, abdominal electrocardiography and ultrasound cardiography are the three …

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 …

Development Of 8052ah-Basic Based Single Board Computer Ii, Suping Lou

Theses

8052AH-BAISC Based Single Board Computer II ( SBC II ) is designed and developed for the application in biomedical instruments as an embedded central processing unit. SBC II offers powerful function in digital signal acquisition, storage and processing, smart on-board EPROM programming, various preipheries supporting and custom supervisor program. The techniques of design and development of SBC II includes computer aided circuits analysis and schematic, optimal design algorithms and computerized setting up SBC II prototype.

This thesis combines the analysis of SBC II circuitry, set up and operation of the complete computer aided electrical circuit design software OrCAD/SDT specifics in …

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.

High Frequency Gaussian Beams Solution Of A Plane Wave Coupling Into Cylindrical Cavity, Christine Issa Mourad

Theses

Propagation of high frequency fields as a superposition of Gaussian beams instead of geometrical ray fields has potential advantages in complicated environments because the beams do not fail in ray optic transition regions. While the Gaussian beam method can be made rigorous through self consistent stacking of displaced and tilted beams on a Gabor phase space lattice, with retention of full beam spectra, computation is facilitated when the propagation domain is covered with paraxially approximated nontilted beams. The spectral deficiencies introduced by this simplified propagation model depend on the propagation environment. They are examined here for a plane wave coupling …

A Dynamic Set-Based Multiaccess Protocol For Local Area Networks, Parul S. Nanavati

Theses

The packet-broadcasting technique brings together the advantages of both packet switching and broadcast communication. The central problem of a packet broadcast network is conflict resolution among the users sharing the broadcast communication link. Collisions are the major source of transmission errors which degrade the performance of a LAN. Proposed here is a novel multiaccess protocol which offers full communication resources to the user at low traffic requirements. It dynamically adjusts the number of users allowed to access the medium at heavy traffic requirements such that number of collisions are reduced and thus maintains the efficient utilization of the medium and …

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 …

Reliability Problems In Semiconductor Lasers, Ajay R. Patel

Theses

The stability and reliability of semiconductor laser is dependent on its design, fabrication, and output power. The best way to assure high reliability of these devices is by accelerated aging test and by selection of strict and meaningful criteria for the acceptance or rejection of a particular device. In this thesis emphasis is given on different failure mechanisms that are known. As new development takes place, other mechanisms may be found. Catastrophic degradation, gradual degradation, darkline defects, and contamination during the fabrication process are the main source of device failure.

The noise generation and the packaging issue of semiconductor laser …

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 …

Image Enhancement And Edge Detection Using Fuzzy Algorithm, Samir Patel

Theses

A method of image enhancement and edge detection by computer using the fuzzy set is illustrated. The algorithm involves extraction of fuzzy properties corresponding to pixels and then succesive application of fuzzy operator 'contrast intensification' along with smoothing in the fuzzy property plane before detecting its edges. The property plane is extracted from the spatial domain using S, π, and (1- π) functions and the fuzzifiers. Edge detection is achieved using KIRSH operator. A computer routine is developed and the effectiveness of the algorithm with different value of the system parameter is demonstrated on different images. The digital computer HP …