Digital Commons Network^™

A Window-Oriented User-Interface For Image Processing Systems On Unix Based Workstations., Sandeep Mehta

Theses

The advent of digital image processing has led to the availability of a very large number of software systems. However there is an absence of a cohesive general-purpose image processing environment isolated from hardware or the underlying operating system. The trend in computing in science and engineering, is towards distributed workstations, especially with the availability of high-performance microprocessors. Hence there is a need for a unified software environment on workstations for use in scientific applications. This thesis describes the design and implementation of a window oriented user-interface. The interface runs on top of a Image Processing system, running on workstations …

Medical Illustration On The Macintosh Personal Computer, Bobby Louis Pitts

Theses

None provided.

Analytical Study Of The Aerodynamic Removal Of Small, Charged Particles From A Dielectric Surface, Carl Bothner

Theses

The need to aerodynamically remove isolated charged particles 50 to 500 micrometers in size from a bed comprised of numerous smaller 10-15 micrometers size charged particles is identified. To facilitate accurate prediction for successful particle removal, a new analytical method is presented for determining the magnitude and location of the aerodynamic drag force acting on a spherical particle in a boundary layer flow. Wind tunnel experiments are conducted on spheres of 2 to 2.5 cm diameter in turbulent boundary layer flow for sphere Reynolds numbers on the order of 10,000. The experiments measure the drag force on the sphere and …

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 …

Effective Techniques For Selection Of Information Systems Personnel, Robert Reginald Downs

Theses

Although major developments in information systems have occurred within the last two decades, staffing to manage these systems has received limited attention. Staffing information systems personnel is investigated in this study to develop effective techniques that can be used in the selection process.

Recent literature on selection and staffing has been reviewed to establish methods that can be used to identify qualified candidates. Technological developments and the resulting effects upon organizational operations are examined, revealing the transition in the information systems management function as well as the effects upon the role of these personnel. The qualifications that are associated with …

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 …

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 …

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 …

On Conventional And Harmonic Load Flow Analysis, Ranjit B. Pradhan

Theses

In conventional power flow analysis, simultaneous linear equations numbering in thousands must be solved repeatedly and in many instances on-line. Luckily the matrix of coefficients of these equations is sparse with a few elements in each row. Therefore for a faster solution and to save computer memory, sparsity must be exploited and an optimal ordering of the equations must be sought. When considering harmonics, the number of the simultaneous equations to be solved is multiplied and therefore, considering sparsity and optimal ordering is doubly important.

In this thesis a software package for optimizing computation time and memory requirements through exploitation …

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 …

An Investigation Of Electrical And Physical Properties Of Reactively, Diode Sputtered Silicon Nitride Thin Films, Divyang Manharlal Shah

Theses

Silicon nitride thin films were deposited by r.f. reactive sputtering of silicon in nitrogen and argon discharge. Biased and unbiased modes of diode mode sputtering were used. Typical parameters for a sputter deposition run were: base pressure, 1-2x10-6 torr; sputtering pressure, 5-7 mtorr; nitrogen partial pressure, 15-16%; cathode-anode gap, 4 inch; r.f. power, 200-250 watts; cathode voltage, 1.8-2.1 V r.f.; water vapor pressure, 20-30% of the base pressure. The film thickness and the refractive index were measured by ellipsometery. The films of thickness 300-2500A, refractive index 1.9-2.1 and resistivity 10101Ω — cm were obtained. The deposition rate was in the …

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 …

A New Hazardous Waste Treatment Technology Utilizing Low Power Density Microwave Energy, Gabriele Else Windgasse

Theses

Two major applications of a new hazardous waste treatment technology using low power density microwave energy have been characterized: 1) Desorption of organic materials such as: trichloro-ethylene, para-xylene, naphthalene and gasoline hydrocarbons from substrates such as: sand and granulated activated carbon was achieved by microwave induced steam distillation and the application of a new phenomenon: arcing between GAC particles when they are exposed to microwave radiation. All contaminants could be removed to 100% (non-detectable with GC and GC-MS). 2) Decomposition of organic contaminants such as: trichloro-ethylene and trichloro-ethane in arcing/heating GAC beds. A new fluidized bed reactor ("RDW-reactor", after Ray, …

Analysis Of Selected Pollutants In Complex Media, Suyi Luo

Theses

Part one: A rapid and reliable procedure is developed for the measurement of the carcinogen benzo(a)pyrene in food. It is a streamlined hybrid of two published methods. These involve ethanalic potassium hydroxide digestion of samples, isooctane extraction, column chromatography on florisil, separation of B(a)P by thin-layer chromatography and measurement of B(a)P by fluorimetry. The recovery of a B(a)P spike of sample is 86.0 + 14.5 % . The procedure which has a limited of detection of 0.05 ng/g (0.05ppb), has been applied to the Human Exposure to B(a)P study.

Part Two: Hexachlorocyclohexane, hexachlorobenzene and some selected PCB congeners were found …

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 …

Culture Analysis In A Merger Environment, Dorairaj Sharathram

Theses

The effects of the merger upon the People Express Airline company is studied with particular emphasis upon changes in corporate culture and structure.

A case study approach utilizes an extensive literature search and interviews with People Express executives. It is confirmed that the structural change has led to the cultural change.

With a unique style of management structure and culture, People Express, due to its own mistakes and problems, quickly lost its market share and allowed itself to be taken over by Continental Airlines a subsidiary of Houston based Texas Air Corp.

It is interesting to note that the corporate …

The State And Future Of Televised Professional Training Systems, Robert Michael Brady

Theses

This paper investigates the topic of televised professional training -- that is training and educating managers and technical professionals via live or videotaped television broadcasts. The investigation begins with a description of how some typical educational networks operate; it then goes on to analyze in a strictly theoretical sense, some of the advantages and disadvantages that such a system would have compared with the traditional methods of offering continuing education; it then discusses the results of two specially prepared surveys -- one addressed to the administrator/manager, and one addressed to the student. These areas are then united in a final …

3-D Reconstruction Of Microvasculature From High Voltage Electron Microscopy (Hvem) Data, Pradip Kumar Paul

Theses

This is a new method for histoarchitectural and volumetric analyses of cell compartments of microvasculature with the use of a unique combination of computerized 3-D reconstruction and HVEM thick serial cross sections. The technology is potentially a reliable, simple, accurate and fast method. Pioneering work in this area was started by Todd et al. (Circ Res Vol :53 p 319 ;1983) basically using light microscopy, but supported by conventional ultrathin transmission electron microscopy. These techniques are important in that they promise to resolve controversies in terms of evaluating the occurance of hyperplasia and hypertrophy in small resistance vessels in various …

Adsorption And Kinetics Of Adsorption By Flyash In Solution, Murthy K. Jogimahanti

Theses

The phenomena of adsorption is extremely important in water/wastewater treatment process. A process which uses flyash as the sorbent for removing organic compounds from aqueous solutions has been investigated. Also, the rate at which this process occurs, i.e., the kinetics of adsorption, has been studied. Single solute systems were examined and the samples were analyzed using a Flame Ionization Detector Gas Chromatograph. The potentialities of adsorption on flyash as a method of renovation of water have not been realized fully, because little knowledge is available regarding the effective application of the method for this purpose.

Flyash has been known to …

Messaging, The Effects Of The Use Of Voice Mail On The Use Of Electronic Mail, Terese M. De Troia

Theses

A number of office automation products have evolved over the years to address the messaging needs of organizations. The 1800's brought us telegraph systems which led the way for teletype and Telex systems, followed by facsimilie, computer-based message systems, document based electronic mail and, most recently, voice store and forward (or voice messaging) systems (Advances in Office Automation, 1985). Voice messaging systems, a newly emerging method of communications, are having a significant impact on communications. The concept of messaging services is rapidly gaining acceptance in business communities (Girishankar 1986, Hirschheim 1985). With costs rising and time becoming more valuable, organizations …

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 …

Integration Of Cad/Cam System Into A Waterjet Cutting Cell, Sanjay C. Shah

Theses

The work is intended to bridge the gap between CAD and CAM fora waterjet cutting cell. The output of CAD is used by CAM directly through the software interface developed. To achieve this, a postprocessor is designed for a two-dimensional system for the series 8200 Allen Bradley's 5-axes Robot Controller. Calma's DDM & DIMENSION III interactive graphics system implemented on VAX was used for the part design. The postprocessor is a computer program, written in the structured FORTRAN, that is unique for a given machine-tool/controller combination. The conversion of the coding and recording format of the APT file to the …

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 …

Pentachlorophenol And Oxygen Consumption Of Immobilized Mixed Bacterial Culture, Tesfamariam Stephanos Tsadwa

Theses

This study was undertaken to investigate the effects of Pentachlorophenol (PCP) concentration on oxygen consumption of immobilized microbial cells. The microbial population, from a municipal wastewater treatment plant, was immobilized in calcium alginate gel. The following studies have also been conducted in this project:

1. Comparison of the effect of PCP concentration on oxygen uptake between immobilized and free cells.
2. Comparison of the effects of PCP concentration on oxygen uptake between acclimated and an unacclimated bacterial beads.

Dissolved oxygen concentration was monitored using a flow Clark-type oxygen probe, in a micro-assay bioreactor. It was found that PCP concentrations higher than 2000ppm …

Design Of A Fiber Optic Oxygen Sensor Based On Immobilized Hemoglobin, Mendu Govind Raj

Theses

The fiber optic Oxygen sensor consists of a thin layer of immobilized deoxyhemoglobin at the common end of a bifurcated fiber. Immobilization is done using the alginate gel procedure. The immobilized reagent is separated from the standard oxygen sample by the gel with or without semi-permeable membrane, and the entire configuration is enclosed in an oxygen free sample cell. Light from a tungsten-halogen lamp, filtered through a 405nm filter is passed through one arm of a bifurcated fiber to the sample cell. The reflected intensity (a highly polished aluminum foil or a plate is placed at the bottom of the …

Seaforms, Karen Louise Wright

Theses

None provided.

Design And Implementation Of A Simulator For A Local Area Network Utilizing An Ibm Pc/At Or Compatible Computer, Christian G. Midgley

Theses

The purpose of this project is to provide a fixture which may be used as a local area network for a course similar to the Small Systems Workshop course (EECC756) as taught in the spring of 1986. This fixture will provide the physical layer of the local area network. This network would be Ethernet like but use an RS-232C communication between the fixture and the nodes. In addition to simulating the ether the fixture would provide for on-line analysis of the packets being sent to provide feedback to the student as well as the professor. The IBM PC/AT type personal …

Microcomputer Graphic Intelligence, Thomas Tillman Shaffner

Theses

None provided.