Digital Commons Network^™

Slotted Aloha Protocol For Packet Transmission Via Satellite Link : Throughput Performance Of Continuous Transmission Packet, Solon Karashialis

Theses

The throughput performance of multi-access schemes for data traffic through a satellite channel is analyzed in this paper. Three general schemes are described: channel reservation schemes, random access schemes, and padket reservation schemes. This thesis considers only the random access schemes. Analysis and comparison between ALOHA and Slotted ALOHA are made, but the main emphasis is on satellite channel throughput. A continuous transmission protocol for Slotted ALOHA is suggested in which each ground earth station repeats the transmission of each packet in a number of random repetition slots. The channel is idle when no ground station (GS) is transmitting on …

The Dewaterability Of Anaerobically-Digested Sludges, Hui-Ching Lee

Theses

Vacuum filtration is the most common method used for sludge dewatering. Filtering or dewatering was operated to reduce the moisture content of the sludge after anaerobic digestion treatment.

The main purpose of this study is to determine the effect of the operating conditions of anaerobic digestion system on specific resistance in sludge filtration. The anaerobic sludges used for the present study were produced from the conventional single stage system and the multiple-stage system. From the experimental results, presently obtained that it is possible to compare the advantage and disadvantage of the two different digestion systems.

In addition, the effectiveness of …

Temperature Scale-Up On Rotating Biological Contactor Nitrification System, Kuanchun Lee

Theses

The relationship between RBC scale-up factor (SUF) and wastewater temperature is successfully developed by using Dr. Wu's mathematical model as a basis and 114 sets of data from the operation of 8 full-scale and 5 pilot-scale RBC plants served for NH3-N removal. The SUF obtained from this study is put into practice to present the scale-up of hydraulic loading for basic full-scale RBC plant design when the pilot study results are known and the design efficiency is fixed. An additional study is made to investigate two different RBC products manufactured by Autotrol Inc. and Lyco Inc. in terms of the …

Evaluation Of Rates Constants In An Isothermal Turbular Reactor, Yu-Hsin Lin

Theses

To view upon an incompressible laminar-flow fluid in fully developed in a plug reactor, in which a layer of catalyst coated on the inside surface of this reactor. Two kinds of reaction will occur : one is bulk ( homogeneous ) reaction, i.e., the reaction of reactants themselves; another is a first-order irreversible catalyst ( heterogeneous ) reaction, i.e., the reaction of reactants and catalysis.It is apparent that two reactipn rate constants, Κ_b for the homogeneous reaction and Κ_ω for the heterogeneous reaction, will be caused because of these two reactions

One partial differential equation after working of …

Study And Characterization Of Ingaas Photodiode And Photodiode Arrays, Krishna R. Linga

Theses

This thesis describes the InGaAs p-i-n photodiodes, photodiode arrays and their characterization. A work station was also built for the opto-electrical characterization. The main feature of the In,_zGa_iAs photodiodes with x > 0.53 is its response to higher wavelengths than the standard lattice-matched photodiodes. An In_xGa_1-xAs photodiode with x = 0.88 respond to 2.6 μm wavelength. The application of these photodiodes is forlIber optic communications, spectroscopy and instrumentation. A complete characterization and analysis of the In_0.88Ga_0.12As photodiodes is presented. Dark current analysis, which is a critical parameter in photodiodes, …

How Effective Is The Union Title Vii Grievance Procedures, Yu-Wen Liu

Theses

Title VII forbids certain kinds of discrimination in employment and establishes a federal forum to enforce employee's rights. It means an employer discriminates against any individual in hiring or discharging, because of such individual's race, color, religion, sex, or national origin.

It has been a long time to use Title VII in unlawful practice employment. Therefore, in my thesis, I investigate the development of labor law, special for the development of Title VII of the Civil Right Act of 1964. Secondly, I emphasize on the individual and union that they can effectively make use of their rights under Title VII. …

Optimization On Isdn In Multihop Radio Networks Through Genetic Algorithm, Prashant H. Pahade

Theses

Integrated service of voice and data on a single network has received considerable attention recently. Various techniques have been proposed and analysed for multiplexing voice and data over a large bandwidth channel. Efficient channel allocation for voice and data on multihop radio network is what we are most concerned about. In this paper, we address the problem of determining optimal access policies for a tandem ISDN network by using Genetic Algorithm. Computer Simulation shows that this leads to the decision which is beneficial to the services of both voice and data in the network.

Holographic Photo-Induced Electrochemical Etching Of Diffraction Grating In N-Inp, Pei-Chen Pien

Theses

Maskless laser-induced etching and plating is a novel technology for etching a three dimensional profile on semiconductor wafers. Using this technique, we may avoid the contaminating mask stage and achieve in-situ monitoring of the on-going process. In this thesis, we have presented findings on light diffraction from an etched pattern in a thin-film cell configuration. We suggest that the etched pattern develops mostly linearly in time with this arrangement, although indirect monitoring of the reaction process such as by light diffraction, should be carefully interpreted. In-situ light diffraction monitoring appear as if light was scattered from an etched pattern developed …

A Petri Net Simulation Tool, Ashish H. Shukla

Theses

A user friendly and highly interactive graphical tool for drawing, editing and simulating translated Petri Net models is developed. This SunView based tool allows simulation to be carried out in the 'step' and 'run' modes. In the 'run' mode it produces a log file of the simulation run which consists of: a) total number of tokens in the net; b) names of the transitions that fired; and c) the system state reached after each step's execution. The tool offers a new solution to the problem of modeling concurrent and interlocked systems, such as computer systems, modular software, flexible manufacturing systems …

Effective Disciplinary Process In Management, Ying-Lung Teng

Theses

The application of discipline is the punitive behavior by the employer to suppress the employee's undesired behavior in the work place. However, there are many considerations have to be concerned when applied discipline.

An organization has to support the supervisor when applying discipline because it gives the supervisor the great power in dealing with problem workers. Organizational policy has to specify the degree of discipline and timing of discipline in order to make the supervisor and the employee have an idea about discipline.

The employee becomes satisfied with supervision when the supervisor uses good leadership skills to manage. In order …

Electrical Measurements Of Mos Structures Fabricated On Etched Silicon Surfaces, Venkata Ramana Vankayalapati

Theses

This thesis details the electrical characterization of thermally grown thin SiO₂ films on virgin and plasma etched silicon surfaces. The electrical characterization techniques employed for the present study are high frequency Capacitance Voltage(C-V) and Current-Voltage(I-V) measurements. The structures used in this study are Al/Polysilicon/SiO₂/Si/A1 capacitors fabricated on n-Si and p-Si substrates. These capacitors with areas in the range of 0.001-0.05 cm₂, were made using various plasma process conditions and etch reactors.

Based on the experimental results of the C-V anlaysis, in comparison of the controls samples with the plasma treated samples, we could not see …

Experimental Study On Filterability Of Leukocytes, Qi Wang

Theses

The filterability of leukocytes treated with A23187, Cytochalasin B, PAF and FMLP and pumped through 5 µm polycarbonate filters at a constant flow rate was examined. The concentration of the four agents was systematically varied. The filtration pressure was continuously recorded for data analysis. The pressure-time curves generally showed multiphasic components, following a small jump step at the beginning of the filtration process. The pressure rise was initially fast (initial faster increased phase, IP) and then rose more slowly (later slower increased phase, LP). The leukocytes treated with A23187 showed increased IP and higher LP values; those which were treated …

Electron Field Emission Through A Very Thin Oxide Layer, Guang Yang

Theses

Field Emission of an emitter covered with a very thin oxide layer is modeled and calculated numerically. The additional barrier due to the oxide layer is included in the tunnelling problem by using the standard WKB method and tunnelling transmission matrix method. The following physical parameters are considered: the oxide barrier height, the oxide conduction band edge electron effective mass, and the oxide dielectric constant. Compared with the Fowler-Nordheim equation, which was derived for a clean metallic emitter, the calculation of this work shows a reduction of the emission current density from an emitter covered with an oxide layer a …

Characterization Of Material Removal In The Course Of Abrasive Waterjet (Awj) Machining, Yu Yang

Theses

The objective of this study is to develop a practical procedure for prediction of the results of abrasive waterjet (AWJ) machining. The first stage of the study involves the development of the technique for prediction of the rate of material removal in the course of abrasive waterjet (AWJ) machining. A new parameter, Exergy Distribution Density (EDD), is introduced and used in order to characterize the cutting conditions. EDD, determined as the kinetic energy of particles delivered to a unit length of the generated surface, is the function of diameters of the sapphire nozzle (Dn) and the focusing tube (Dc), the …

Simulation Based Modeling And Scheduling Of A Generalized Flow- Line, Srinivas Anne

Theses

Simulation is a state of art technique, widely used to analyze the behavior of complex and dynamic real time systems. This study consists of two parts. The first part involves in the development of a simulation model of a real time flow line, used to assemble Printed Circuit Boards. The desired performance measures of the system, like, utilization, starving, blocking, failure and maintenance are recorded. The model developed can be used as a test pad to analyze scheduling rules and heuristics. This is illustrated in the second part of the study which consists of studying the behavior of the Apparent …

A Proposed Model For Comparing The Performance Of Neural Networks And Statistical Approaches In Predicting Project Profits Of An Asphalt Paving Company, Josephine Giaimo

Theses

It is currently assumed that the performance of a model for predicting project profits of an asphalt paving company varies with an unknown number of parameters. An earlier study indicates that the parameters are not well understood (Berry, 1990). A search of the literature suggests that the available models usually are described by those who develop and use them as universally reliable and valid tools for solving complex problem (Allman, 1989; Bumke, 1988; Clark, 1988; Cohen & Howe, 1988; Fillon, 1989; Kling, 1990; Lawrence, Petterson, & Hartzberg, 1990; Marose, 1990; Pollak, 1988; Reynolds, 1988; Sullivan & Reeve, 1988; Thurber, 1988). …

Design And Development Of Ccd Camera For Document Scanner Using Optical Fiber Bundle, Aniruddha P. Joshi

Theses

A CCD camera for the gray scale document line scanner has been designed and developed at Photon Imaging Corp. The scanner consists of a revolutionary optical fiber bundle, CCD camera, and control electronics. The key concept resides in the fiber-optic bundle. At one end it has a linear array of equally spaced light guides. These terminate at the opposite end in a square array with a polished surface for viewing by a camera. The fan-out from linear to square end is not done with attention to ordering, so the bundle may be relatively inexpensive. Reordering is done electronically using an …

Finite Element Analysis Of Torsional Concentric Composite Shaft Using Isoparametric Circular Element, Yee-Haur Wong

Theses

Finite Element Method is used to analyze the concentric composite material shaft subjected to torsion. Isoparametric circular ring element has been formulated to solve the one-dimensional problem. An intermaterial element at the interface has been developed to accomodate the changing modulus of rigidity.

Solutions of Prandtl's stress functions are used to compute shear stresses and torque in the composite shaft. Results of torque of the composite shaft are established using convergence tests of homogeneous solid and hollow shafts. Good agreement with classical solutions are obtained for homogeneous solid and hollow shafts.

A Torsional Concentric Composite Chart has been developed showing …

Wideband Microstrip Antenna Optimization, Amer Muhammad Alsawadi

Theses

An annular ring patch microstrip antenna was investigated numerically from the bandwidth aspect for a satellite link application. The desired portable antenna should occupy the physical volume of a typical briefcase and operate in the 400-500 MHz band. Numerical optimization is carried out using a commercially available computer package (EM, by Sonnet Software Inc.). The parameters optimized include the substrate thickness, feed location along the annular patch antenna and its relative dimensions. The software package was numerically validated for the rectangular patch geometries reported in the open literature. Experimental verification of this work is left to be carried out in …

A Training Module For The Integration Of Text, Scanned Graphics, And Computer-Generated Artwork Into A Page Layout Program On A Macintosh Design System, Linda A. Jackson

Theses

The purpose of this study is to develop a training module for integrating text, artwork, and graphics into a page layout program. Currently, the information for successful integration must be referenced from several sources. By having the key elements of integration in one volume, users attempting to layout and/or design a publication using these programs will be able to proceed quickly with fewer technical problems. Rapid growth is predicted for computer-based tools in graphic design studios, advertising agencies, and magazines which normally use computer design stations. These computer design stations require proper training to be used cost effectively. Consequently, training …

Relationship Between Chromatographic Retention And Donor And Acceptor Numbers, Peter J. Michelsen

Theses

The prediction of chromatographic retention times for a wide range of chemical compounds has been a subject of interest and intense study during the past few decades. Several of these studies are discussed, in particular those which utilize empirical parameters of solvent polarity in a correlation to chromatographic retention. Several of these empirical scales of solvent polarity are discussed in detail. The compilation of accurate acceptor and donor numbers is thoroughly discussed. Correlation of some of these empirical parameters to the solvent's normal phase liquid chromatographic retention was attempted. The multiple variable correlation equation which resulted in the best correlation …

A Ccd Based Bidirectional Spectral Reflectance Field Instrument, Michael H. Davis

Theses

Accurate interpretation and maximum use of multispectral data acquired from spaceborne and aircraft instruments require increased knowledge and understanding of the bidirectional reflectance distribution function (BRDF) of earth scene elements. Knowledge of the relationships between the spectral characteristics and important parameters of earth surface features can best be obtained by carefully controlled studies over areas, fields or plots where complete data describing the condition of targets is attainable and where frequent, timely spectral measurements can be made. The Bidirectional Spectral Reflectometer (BuSTeR) described in this thesis was developed to provide the Digital Imaging and Remote Sensing Laboratory (DIRS) with the …

Comparison Of Methods For Generation Of Absolute Reflectance Factor Measurements For Brdf Studies, Xiaofan Feng

Theses

For remote sensing applications, there is a need for knowledge concerning the reflectance properties of natural and man-made materials as a function of measurement geometry and wavelength. This information is used to determine the so-called bidirectional reflectance distribution function (BRDF). This study is intended to generate an absolute bidirectional reflectance factor for BRDF studies. This is accomplished by development of a goniospectroradiometer which can simulate any source-sensor-target geometry. The spectral range is from visible to near- infrared (2500 nm) with a spectral resolution of 10 nm. The study involves both theoretical and experimental work for calibration of BRDF by: (1) …

Collage And Installations: Between The Sky And The Earth, Misun Hong

Theses

My work comes from my feelings about abortion. It is a difficult situation for all involved. It is a painful decision for a woman to make, one which not only affects her life but also that of a fetus and other people close to her. I wanted to inform others about the chaotic and complicated sadness that abortion brings to one experiencing it. A woman may ask, "Why do I have to make this decision? I have always tried to be a good person. Why me? Why woman? Why not men? Who's fault is this? I feel trapped, but in …

American Dreams, Mark Lyons

Theses

The intention of this thesis is to investigate metaphorical narratives about experiences in American life. The commentaries depict cultural ironies and satirical imagery of everyday activity. The vessel is used as a stage for these metaphors. I used various glazes, stains, and atmospheres in firing, multiple techniques in construction, and a collection of common historical and personal imagery in each piece. A narrative environment appeared to be the best mechanism to convey statements in the vessels. This body of work reflects many of the experiences I had as a child. These experiences translate into many of the values our society …

Modification Of Organic Polymers With Vacuum Ultraviolet Radiation From Inert Gas Plasmas Rotating In A Magnetic Field, Jian-Xin Chen

Theses

DC arc plasmas containing He and Ar, which were made to rotate by the application of a magnetic field, were used for generating vacuum UV light (VUV) to modify polymer surfaces. Polymers such as poly(tetrafluoroethylene) (PTFE), fluorinated ethylene propylene copolymer (FEP), polyimide (PI), UPDLEX-S and UPILEX-R were modified with and without optical filters for different exposure times. PTFE was also exposed to helium and argon arc plasmas at different exposure temperatures. After the treatment, the polymerfilms were measured by weight loss, contact angle and Scanning Electron Microscopy (SEM). Copper was sputter deposited onto some of the treated samples and the …

Conventional And Differential Scanning Optical Microscopy Using Higher-Order Gaussian-Hermite Beam Patterns, Peter Chrusch

Theses

This thesis addresses the problem of contrast in scanning optical microscopy by resorting to differential imaging. The use of a unique, two-wavelength laser as the coherent source in a scanning format is investigated. In particular, it is shown that the TEM10 mode of this laser provides a novel method for performing simultaneous conventional and differential microscopy. Results are presented on the use of the laser for performing differential imaging. In addition, the technique is extended to encompass a second, tunable, laser. Rather than performing electronic differentiation, the TEMi0 mode of this, second, laser provides an in-situ, optical differential microscope. Two …

Analysis Of Umberger's Theory For Subtractive Color Reproduction, Paul R. Bartel

Theses

A method, proposed by Umberger, for the identification of additive stimuli representative of the red, green, and blue primaries controlled by dyes obeying Beer's law was examined. The primary stability study suggests that for a set of colors created of various dye concentrations, the pattern of Umberger's primary distribution is a translation of the original colors on a chromaticity diagram. Results of a theoretical color reproduction study where the colormatching functions of Umberger's primaries were assumed as the color reproduction system's spectral sensitivities indicate an increase in metric chroma of reproduced colors. Color reproduction errors for a large number of …

Striking Visual Contrasts, Pei-Yung Chou

Theses

In the thesis, I plan to make experiments mainly about blending graphic forms in painting, possibly combining all kinds of different forms that I am interested in, for instance, Expressionism, Hard-edge, Symbolism, Abstractionism, and Realism to create a striking visual contrast. Simultaneously, I hope to research the following areas during the development of the work. (They will influence the pictorial effects to some degree.): 1 The relation between the artwork and the exhibition space. 2.The extension of painting in terms of reconstituting or changing the order of complete paintings. In my final work, I spent most of my time on …

The Design, Fabrication, And Test Of A Cmos Operational Amplifier, Edward P. Sayre

Theses

The topic of this thesis is the design, fabrication, and testing of a CMOS operational Amplifier. This Operational Amplifier was first realized as a class design project for Advanced Analog IC design. Specifications for the device performance were determined by Dr. Fuller and Edward Sayre to enable the op-amp to be incorporated into a larger more complex design. The specifications of the operational amplifier were made to enable design integration into an amplifier which would operate in the audio frequency range. The main constraints placed on the design of the op-amp were low power consumption and a relatively moderate gain.