Engineering Commons^™

Some Reasons Why New Technologies Are Not Always Successful - Specifically Directed Toward Cim, Shuk Fong Lai

Retrospective Theses and Dissertations

To keep the competitive edge, many companies constantly implement new technologies. However, the implementation of these new technologies are not always successful. Why?

Problems with implementation of new technologies can be either technical or managerial. This paper presents research limited to management problems and suggests the necessary changes. It also outlines the important factors in the decision-making process and the criteria for a successful implementation of a Computer Integrated Manufacturing (CIM) system. Many experts believe that CIM is the ultimate solution to slow and reverse the decline of the U.S. global manufacturing market. However, some companies that have implemented CIM …

The Application Of Transfer Matrices In The Dynamic Analysis Of Planar Elastic Mechanisms, Richard Kent Lindenberg

Retrospective Theses and Dissertations

Transfer matrices are used in the dynamic analysis of planar elastic mechanisms. Mechanism motion is discretized by dividing the motion into a finite number of intervals over which the mechanism is considered to be an instantaneous structure with constant geometry. Transfer matrix methods are then used to calculate the natural frequencies and corresponding mode shapes of the instantaneous structure. A transfer matrix relating the continuous, non-zero components of the state vector across a pin joint is developed. An elastic four bar mechanism and a crank slider mechanism with a rigid crank and elastic connecting rod are analyzed using lumped mass …

A System For Measuring The Phase Difference Between Two Points Of A Propagating Laser Beam, Jefferson E. Odhner

Retrospective Theses and Dissertations

An optical system has been designed, analyzed, implemented, and calibrated which measures the phase difference between two points of a propagating laser beam. The system is a quadrature interferometer whose detector outputs are processed by a computer. This quadrature interferometer measures both the phase and amplitude variations between two points of a laser beam after the beam passes through turbulence . These measurements are in turn processed by a computer to isolate the phase variations from the amplitude variations. Further statistical analysis which can be performed on these phase variations should provide an understanding of the phase fluctuations of propagating …

Method For Sizing Mos Transistors For Vlsi, Matthew J. Amatangelo

Retrospective Theses and Dissertations

Determining the device width to length ratios has typically been an iterative process for the custom IC digital design engineer. After the logic design phase is complete for a particular circuit, the designer would make an educated guess at the device sizes. Then by trial and error, using SPICE or another circuit simulator, suitable sizes would be determined. Unfortunately, this approach is time consuming and the resulting sizes are often a good bit larger than they need to be to maintain a certain speed because of the lack of a rigorous sizing methodology. This paper describes a method for reducing …

A Proposed System For Determination Of Percent Cloud Cover, Carol L. Emrich

Retrospective Theses and Dissertations

A method for determining percent cloud cover by taking two consecutive images using different color contrast filters, specifically a red filter and a blue filter, is described. This method (RF/BF estimate) involves dividing the "red" image by the "blue" image, pixel by pixel, and determining the percentage of pixels in the resultant image with intensity values of one. This is the percent cloud cover. The RF/BF estimate is based on the different effects of molecule and particle scattering of electromagnetic waves in the visible portion of the spectrum. These two types of scattering, Rayleigh and Mie scattering respectively, are described …

The Design Of A Dual Method Metal-Organic Chemical Vapor Deposition System, David B. Cox

Retrospective Theses and Dissertations

For the fabrication of semiconductor devices, solar cells, and infrared detectors, thin film deposition methods are required. Of the deposition methods currently available including MBE, LPE, and MOCVD; MOCVD is preferred due to its relatively low cost per wafer, versatility, and high wafer throughput. Requirements which must be considered in the design of a deposition system are discussed. An MOCVD system is designed such that MOCVD can be carried out by plasma enhanced deposition (PED) or low pressure metal-organic chemical vapor deposition (LPMOCVD). As a result of the inherent characteristics of the two methods, a wide range of operational temperatures …

Effects Of 0.5 Weight Percent Boron On Cobalt Aluminide, Kevin Thomas Slattery

Masters Theses

"A study was made on the effects of adding 0.5 weight percent boron to the ordered intermetallic Cobalt Aluninide. Thirty gram (30g) specimens were induction melted in an pure argon atmosphere and cast into a copper alloy bar mold. The addition of boron raised the modulus of rupture from 30.1 to 44.3 ksi; increased the Knoop microhardness from 543 to 693; reduced the average grain size from 190 to 70 microns; and gave a more equiaxed grain structure. X-ray diffraction detected the presence of a second phase, AlB , 12 in the material containing boron. Scanning electron micro-scopy revealed that …

Paraffin Deposition Property Measurement Using Differential Scanning Calorimetry, Kevin Lynn Thornsberry

Masters Theses

Differential Scanning Calorimetry (DSC) has been used in past studies to identify the cloud points of diesel fuels, lube oils, jet fuels etc. and it has been assumed that its application extends to all paraffinic hydrocarbons. To verify this and to investigate the possible application of Differential Scanning Calorimetry to the production phase of the petroleum industry, the onset of wax crystallization is compared with ASTM cloud point for a number of paraffinic mixtures including a variety of crude oils. Results show cloud point can be determined for crudes using DSC. Additionally, wax content can be found on a known …

Optimizing Transformer Impedance For Short Circuit Analysis, Louis Scott Becker

Masters Theses

"Transformer impedances change when the tap positions on the primary or secondary are changed. Models were designed that gave the maximum impedance variation for a large percentage of transformers studied. These models were used to study how fault currents deviated from the predicted values if the actual transformer impedance was not the same as the predicted impedance. The effects of the change in turns ratio was also taken into account, and the base voltages were chosen to be different from the transformer voltages to include this possible error.

Faults were placed on the secondary of a model radial power system, …

Behavior Of Reinforced Loess Specimens Under Triaxial Load, Mohammad Taghi Izadi

Masters Theses

"Effects of reinforcement on shear strength of a loessial (silty) soil arc studied. Unconsolidated undrained triaxial tests are performed on unreinforced and fabric reinforced soil specimens. Analyses of the test results showed that in general the shear strength of remolded loess specimens were improved substantially and increase in the shear strength was directly related to reinforcement spacing.

The mechanism of soil-reinforcement interaction and several existing analytical models are described. A modified analytical model based on enhanced confining theory is developed. This model can be used in assessing the effects of the reinforcement on shear strength of triaxial specimens. Comparison of …

Vle For 1,3-Butadiene With 1,2-Butadiene And Propyne, Patrick J. Gripka

Masters Theses

"Vapor pressures for pure 1,3-butadiene, 1,2-butadiene and propyne and 10 binary mixtures are reported at 5, 20, 35, 50, and 65°C. An equation of state utilizing saturated vapor and liquid densities is used to correlate the experimental data. Calculated relative volatilities and saturated densities are reported for the systems 1,3-butadiene - 1,2-butadiene and 1,3-butadiene - propyne. The thermodynamic excess functions Helmholtz free energy, Gibbs free energy, entropy, enthalpy, internal energy, volume, and heat capacity are derived for the equation of state and the excess properties are reported for the two systems"--Abstract, p. iv.

The Effect Of Phosphate Additives On Alumina, Alumina-Calcia, Alumina-Silica Refractory Castable Systems, Sukendro Widjaja

Masters Theses

The effects of the addition of phosphate chemicals to Al₂O₃, Al₂O₃-CaO, and Al₂O₃-SiO₂ systems have been studied concentrating on selected dry and fired properties. The various refractories evaluated were formulated from all alumina aggregate systems based on 1) a mix of tabular and calcined fine aluminas, 2) a combination of calcium aluminate cement bonded-tabular and calcined fine aluminas, and 3) an alumina aggregate-silica fume mixture. Specimens were vibration-cast, dried at 110°C and fired at 1450°C. It was found that each system has different property responses to different …

Sessile Drop Studies Of Aluminum On Sapphire, Ke Wen K. Li

Masters Theses

A sessile drop technique employing a drop placement method has been used to investigate the wetting behavior and interfacial phenomena between aluminum and single crystal α-alumina. Measurements were made under a flowing mixture of H₂ and He atomsphere from 1200°C to 1600°C. Acute contact angles decreased continuously in all cases during the 8-hour experimental time. Neither the oxygen partial pressure of the flowing gas nor the orientation of the single crystal alumina substrate affected the contact angles, but the shapes of crystals grown at the substrate-metal interfaces were dependent on the orientation of the substrate surface to some extent. …

An Experimental Study Of Adsorption And Variable Temperature Desorption Of Ethanol-Water, Propane-Propylene And Hydrogen Sulfide-Carbon Dioxide-Propane, Suvit Kulvaranon

Masters Theses

"An ideal adsorption only removes the desired components. Many times one or more other components are also adsorbed. If two or more components are adsorbed, an adsorption separation may not be satisfactory or may require additional separation procedures, even though one is highly preferentially adsorbed. In such cases it may be possible to get additional separation during the desorption stage by using variable temperature desorption.

To study such problems, two experimental apparatus were set up, one for adsorption for ethanol and water mixtures on activated carbon and silicalite, the other for propane-propylene mixtures, and hydrogen sulfide-carbon dioxide-propane mixtures both on …

Fabrication And Mechanical Property Analysis Of A Transparent, Glass Fiber Reinforced Polymer Matrix Composite, James R. Olson

Masters Theses

"A "transparent” composite was produced by reinforcing poly(methyl methacrylate) (PMMA) with unidirectional borosilicate glass fibers. Composites with 40 volume percent fiber had a modulus of rupture of 600 MPa which is six times greater than that of pure PMMA. Young's modulus for the same composite was 18 MPA which is nine times greater than the 2 MPa measured for pure PMMA. Work of fracture was 110 kJ/m² or more than double the 45 kJ/m² required to fracture pure PMMA. The optical transmission of the composite with 30 volume percent fiber was approximately 40 percent through a 10 mm …

A Three-Dimensional Bistatic Radar Target Position Measurement Error Model, Robert Kenneth Lynn

Masters Theses

"The accuracy of target position measurements for an airborne bistatic radar receiver are calculated. Two methods of information measurement are utilized, both of which assume cooperative synchronization between the transmitter and receiver. Gimbal angle errors are incorporated into both methods. The size and orientation of the error ellipsoid about the true target position is found. Loci of constant circular error probable are plotted in a horizontal plane of interest"--Abstract, page ii.

The Effect Of Additives On Properties Of Pfn-Pfw Dielectric Materials, Weih-Min Liao

Masters Theses

"The purpose of this study was to investigate the effect of processing and additives on the properties of the Pb(Fe_1/2Nb_1/2)O₃-PB(Fe_2/3W_1/3)O₃ solid solutions. The basic composition was 70 m% Pb(Fe_1/2Nb_1/2)O₃ and 30 m% Pb(Fe_2/3W_1/3)O₃. The additives used were MnO, PbO and ZnNbO₆. Pressed compacts were sintered over the temperature range 900'C to 1050°C for 1 to 5 hours.

The influence of processing and composition on the properties was determined by measurement of density, shrinkage, dielectric constant, dissipation factor and …

Reductive Stripping Of Iron(Iii) From Di(2-Ethylhexyl) Phosphoric Acid, Byron G. Belew

Masters Theses

"Unwanted impurities, present in raw materials, are often coextracted along with desired constituents during leaching. If left unchecked, impurity levels may increase in hydrometallurgical process streams until their presence has deleterious effects upon subsequent unit processes. Due to its abundance and ease of extraction, the presence of ferric iron in solvent extraction circuits has always been a problem. The technique proposed herein constitutes a novel approach to remove iron from zinc hydrometallurgical circuits; but the principles employed may find a variety of applications.

This research investigated the reduction and stripping of ferric iron from di(2-ethylhexyl) phosphoric acid into a …

Ion Exchange Properties Of Titania Gels Prepared From Titanous Chloride And Amonium Carbonate, Nahed Latif Yacoub

Archived Theses and Dissertations

No abstract provided.

Numerical Solutions Of Poisson's Equation In A Superlatice Device, Norman Todd Rollins

Retrospective Theses and Dissertations

The relationship between the built-in potential and the energy bands in a heterojunction device is defined using the Anderson model. Based on this model, Poisson's equation for a nonhomogeneous semiconductor device in thermal equilibrium is derived and solved analytically for the special case of a doubly intrinsic abrupt heterojunction. Several numerical methods of solving Poisson's equation for general cases are explored to find the most efficient method. The validity of the chosen numerical method is tested against both the analytical solution for a Ge/GaAs doubly intrinsic diode and recently published results from similar numerical simulation studies. A p-i-n superlattice device …

Dynamic Allocation Of Responsibility Between Operators With Different Models Of System Information Using Computer-Mediated Communication, Michele Terranova

Psychology Theses & Dissertations

This research focused on the effectiveness of two operator teams for dynamic control of a process simulation. The responsibility for system optimization and failure detection was shared by the operators through computer-mediated communication. System information was displayed to both operators by one of three mental models of the systems: an alphanumeric/separable representation, a graphic/integral system representation, or both representations. The following team-display configurations were used: primary operator with graphic display, support operator with alphanumeric (GRAL); primary operator with alphanumeric display, support operator with graphic (ALGR); both operators with alphanumeric displays (BOAL); both operators with graphic displays (BOGR); and both operators …

A Simple Solid-Phase Electrophoretic Procedure For The Separation Of Plasmid Dna, Linda Ann Simurra

Biological Sciences Theses & Dissertations

A method was developed for extraction of plasmid DNA from bacterial cells embedded in agarose blocks. Cell - containing blocks were treated with various lysing reagents and inserted into the wells of an agarose gel. Upon electrophoresis the plasmid DNA migrated out of the embedding block and into the gel leaving intact chromosomal DNA in the well. This method was tested with various organisms and found to be effective for plasmid isolation. In comparison to "traditional" procedures, this new method is less tedious since chemical separation of plasmids is not required prior to electrophoresis. Also, a higher yield of plasmid …

A Modified Extended Kalman Filter As A Parameter Estimator For Linear Discrete-Time Systems, Bruno Johannes Schnekenburger

Theses

This thesis presents the derivation and implementation of a modified Extended Kalman Filter used for Joint state and parameter estimation of linear discrete-time systems operating in a, stochastic Gaussian environment. A novel derivation for the discrete-time Extended Kalman Filter is also presented. In order to eliminate the main deficiencies of the Extended Kalman Filter, which are divergence and biasedness of its estimates, the filter algorithm has been modified. The primary modifications are due to Ljung, who stated global convergence properties for the modified Extended Kalman Filter, when used as a parameter estimator for linear systems.

Implementation of this filter is …

Accelerator Waveform Synthesis, Jay Wilson Heefner

University of the Pacific Theses and Dissertations

The Induction Linac System Experiment (ILSE) is a heavy-ion fusion (HIF) device that is being designed at Lawrence Berkeley Laboratory (LBL). The machine will be capable of accelerating 16 carbon ion beams, which are subsequently merged into 4 beams, to energies in the neighborhood of 10 MeV (10 million electron- volts). The purpose of the experiment will be to demonstrate the process of simultaneous acceleration and current amplification for a multiple beam accelerator configuration. If this process can be mastered, the beams produced by a machine such as ILSE would be used to implode and heat a deuterium-tritium (D-T) fuel …

Toward The Development Of A Knowledge-Based Construction Schedule Planning System, Nordin Bin Yunus

Doctoral Dissertations

"This research attempts to model and prototype a knowledge-based system for use in the construction industry to accomplish the automatic generation of initial construction schedules. The schedule can be transformed into a logical network that provides a physical representation of the construction operations plan. The prototype system, which requires symbolic processing and reasoning, is developed based on an intensive modeling that rationally examines industry practice.

The model identifies work breakdown and precedence relationship as the two major concepts in schedule planning. Work breakdown is concerned with the identification of construction activities that result in the completion of project elements. Precedence …

An Analysis Of The Abaca Natural Fiber In Reinforcing Concrete Composites As A Construction Material In Developing Countries, Rolando V. Magdamo

Dissertations and Theses @ UNI

This study was undertaken to analyze the flexural and splitting tensile strengths and the ductility of abaca fiber-reinforced concrete composites. Abaca fibers are natural fibers of vegetable origin prepared from the abaca plant which is a native plant of the Philippine Islands. The purpose of the study was to investigate how various volume-fractions of the abaca fiber in the concrete mix could affect the mechanical properties of the concrete matrix.

A concrete design mix containing a volume ratio of 1.0 part Type I Portland...cernent and 3.0 parts sand was utilized in the preparation of laboratory test samples. Abaca fibers were …

The Importance Of Computer-Based Subject Matter Topics For Graduates Of An Undergraduate Manufacturing Technology Program As Perceived By Practicing Manufacturing Engineers, Anthony Cecil Favre

Dissertations and Theses @ UNI

The problem of this study was to identify the perceptions of practicing manufacturing engineers regarding the importance of computer-based subject matter topics required for graduates of undergraduate manufacturing technology programs. This problem is reflective of the literature which indicates that there is a need for the further development of manufacturing science curricula in order to provide the types of knowledge needed in the emerging computer-based manufacturing field.

A questionnaire was used to collect data. It was mailed to 425 randomly selected practicing manufacturing engineers. Thirteen were returned as undeliverable, thus reducing the number to 412. The size of the sample …

An Experimental Cost Model For The Analysis Of Quality Cost In A Manufacturing Enterprise, Wallace Charles Carlson Jr.

Dissertations and Theses @ UNI

The intent of the study was to construct a quality cost model for manufacturing enterprises. A quality cost model provides a manufacturing enterprise with a cost structure which enables it to gauge and measure the efficiency and effectiveness of its management and processes. The quality cost model was specifically constructed to aid a manufacturing enterprise in establishing a quality cost system for its operations and activities and contains three distinct initial implementation or decision areas; the quality cost management decisions area, the quality cost system applications area, and the quality cost system utilization area.

The quality cost model was evaluated …

Fundamental Concepts Required By Electromechanical Technology Graduates For Entry-Level Employment In Related Industry, Julio R. Garcia

Dissertations and Theses @ UNI

The objective of this study was to determine the fundamental electromechanical concepts needed by electromechanical technology graduates to perform efficiently at the entry-level employment in related industry. An extensive review of the literature indicated that it was necessary to prepare electromechanical technologists with emphasis given to the area of electrical/electronics technology, mechanical technology, fluids, and fiber optics. Thusly prepared, these graduates would be able to service modern industrial equipment and would have greater opportunities in the job market than at present.

A Likert format questionnaire was developed to gather the necessary data. The survey instrument consisted of 91 concept statements …

The System Design And Evaluation Of A Microprocessor Controlled Dispenser Using A Radar Ground-Speed Sensor, Yu-Charn Chen

Dissertations and Theses @ UNI

This experimental research focused on the design of a new approach to control seed dispensers and to analyze the performance characteristics of a Doppler radar ground speed sensor for a microprocessor control dispenser. The research focused on comparing the effectiveness of using a radar unit with a fifth-wheel encoder for measuring ground speed when both were connected to a microprocessor controlled seed dispenser.

The system designed for this study consisted of hardware and a computer program in 6502 assembly language. The hardware for this study consisted of a monitor device, microprocessor control unit, stepper motor, fifth-wheel encoder, Doppler radar and …