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Full-Text Articles in Engineering

Information Technology And Wealth: Cybernetics, History And Economics, Elin Whitney-Smith Jan 1991

Information Technology And Wealth: Cybernetics, History And Economics, Elin Whitney-Smith

Engineering Management & Systems Engineering Theses & Dissertations

Capitalism developed where and when it did because there was high information access. There was high information access because of a major advance in information technology--the press. Where the technology was not controlled by the "powers that be" there was economic growth and a shift in the entire social structure. Where it was controlled there was no structural change and there was economic ruin. The development of capitalism is a major step change in economic growth. It is also a major change in the way people organize themselves into groups.

Major step changes in the growth and in the organization …


Effect Of Passive Flow-Control Devices On The Drug Of A Tractor-Trailer Model, Jagjit K. Ahuja Jan 1991

Effect Of Passive Flow-Control Devices On The Drug Of A Tractor-Trailer Model, Jagjit K. Ahuja

Mechanical & Aerospace Engineering Theses & Dissertations

The aerodynamic drag of tractor trailers is responsible for approximately half of the fuel consumption at highway speeds (55m.p.h.). Thus, it is important that vehicle drag be reduced in order to reduce operating costs and to conserve fuel. The purpose of the subject research conducted in the Old Dominion University Low-Speed Wind Tunnel was to determine the effect of various add-on flow-control devices, such as a cab-mounted flow deflector and gap seals between the tractor and the trailer. In addition, the effect of trailer rear-edge shaping has been studied. This was accomplished by contouring the trailer's rear end. It has …


Toward The Optimization Of Cell Operator Productivity In Computer Integrated Manufacturing, David Leonard Gobeski Jan 1991

Toward The Optimization Of Cell Operator Productivity In Computer Integrated Manufacturing, David Leonard Gobeski

Dissertations and Theses @ UNI

Computer integrated manufacturing (CIM) has been seen as the answer to maintaining the lead in American productivity. The cell operator was seen as being critical to the success of CIM. The design of the operator's job was seen as very important. As manufacturing engineers design cell jobs, including the roles and tasks, with the operators, it was believed important for the engineer to know what motivated the cell operator. However, past studies of supervisors and their subordinates have shown that supervisors are unable to predict the importance of the elements of job enrichment of the subordinates. It was questioned whether …


Factors Influencing Preparation Needed Of Future Industrial Technology Department Leaders In Higher Education, Rajendra L. Desai Jan 1991

Factors Influencing Preparation Needed Of Future Industrial Technology Department Leaders In Higher Education, Rajendra L. Desai

Dissertations and Theses @ UNI

The object of this study was to help future industrial technology department leaders in higher education develop effective planning strategies and prioritize their preparation before they sought leadership positions in industrial technology. Two hundred fifty-four industrial technology department leaders in higher education from all over the United States were asked to respond to a questionnaire. A five point Likert-type scale was used to rate the importance of 58 statements identified from Marshall's (1984) study. One hundred sixty (62.99%) usable responses formed the basis of this study.

Mean values and standard deviations were determined for all the statements. The grand mean …


Perceived Importance Of Identified Duties And Tasks In The Area Of Design/Drafting Management, John Edward Shultz Jan 1991

Perceived Importance Of Identified Duties And Tasks In The Area Of Design/Drafting Management, John Edward Shultz

Dissertations and Theses @ UNI

The purpose of the study, was to determine the importance of identified duties to the career success of a newly hired design/drafting employee aspiring to become a supervisor or manager as perceived by design/drafting managers and university professors. An opinionnaire was developed which consisted of 141 tasks which were grouped into 13 general duties. The 13 duties represented the job functions for design/drafting managers. The opinionnaire was validated utilizing a jury of experts consisting of eight design/drafting managers and five university professors. It was then mailed to the membership of the American Design Drafting Association (ADDA) who identified themselves as …


Surface Treatment Of Cast Iron By Adding Different Alloying Elements To Form Metallic Glass Structure Layer Using An Industrial Carbon Dioxide Laser, Mohammad Riahi Jan 1991

Surface Treatment Of Cast Iron By Adding Different Alloying Elements To Form Metallic Glass Structure Layer Using An Industrial Carbon Dioxide Laser, Mohammad Riahi

Dissertations and Theses @ UNI

Wear and corrosion are the two factors that make utilization of metals very costly. Extraordinary amount of time and money is spent to replace metallic parts affected by either wear or corrosion. Cast iron that is used very widely in a host of different industrial products is one such metal. Among the various methods used to improve the properties of metals, production of amorphous metals is highly noticeable. This process is done by treating the base metal in a certain technique which produces a metal that is more resistant to wear and corrosion.

This study was conducted to examine the …


On Local Stresses And Spring Constants Of Pipe-Nozzle Connection, Hson-Chih Sun Dec 1990

On Local Stresses And Spring Constants Of Pipe-Nozzle Connection, Hson-Chih Sun

Dissertations

This thesis presents a comprehensive study of local stresses and spring coefficients of pipe with a nozzle connection, analyzed by the finite element method (FEM). Six types of loading are discussed: radial force, circumferential moment, longitudinal moment, circumferential shear force, longitudinal shear force, and torsional moment.

For the local stresses, the bending and membrane stress factors due to each of these loadings are presented in a series of plots with various gamma (piping radius/thick-ness) and beta (nozzle radius/pipe radius) values. These stress factors will readily replace those previously published in WRC No. 107. This work not only gives more accurate …


Wideband Microstrip Antenna Optimization, Amer Muhammad Alsawadi Dec 1990

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 …


Adaptive Stack Filtering By Lms And Perceptron Learning, Yu-Chou Huang Dec 1990

Adaptive Stack Filtering By Lms And Perceptron Learning, Yu-Chou Huang

Theses

Stack filters are a class of sliding?window nonlinear digital filters that possess the weak superposition property(threshold decomposition) and the ordering property known as the stacking property. They have been demonstrated to be robust in suppressing noise. Two methods are introduced in this thesis to adaptively configure a stack filter. One is by employing the Least Mean Square(LMS) algorithm and the other is based on Perceptron learning.

Experimental results are presented to demonstrate the effectiveness of our methods to noise suppression.


Estimating 3-D Motion And Structure Parameters Of A Rigid Planar Object By Establishing Landmark Correspondences, Herman Agustiawan Dec 1990

Estimating 3-D Motion And Structure Parameters Of A Rigid Planar Object By Establishing Landmark Correspondences, Herman Agustiawan

Theses

The application of a landmark based approach in recognizing 3-D rigid planar objects[3] along with two different motion and structure estimation algorithm [21][23] have been studied to perform motion and structure estimation tasks of moving objects. The recognition algorithm is based on a sphericity value derived from affine transformation that maps feature points in the object under observation from first to second view in the 2-D image space. The motion and structure estimation algorithm is based on a unique mapping given four or more feature point correspondences.

More than ten experiments have been done including small and large rigid motions. …


A Transistor Delay Model Based On Charge Conservation, Bharatsingh K. Bisen Dec 1990

A Transistor Delay Model Based On Charge Conservation, Bharatsingh K. Bisen

Theses

Delay information of a circuit is often used in the areas of timing verification, timing analysis, race detection and circuit optimization. Given a circuit its delay can be estimated by various simulation techniques. SPICE is one of the simulation techniques, but it is seen that with the increase in the complexity of the circuit the SPICE circuit simulation technique to obtain delay information become cumbersome and computationally too expensive. So as to overcome the above disadvantages of the circuit simulation technique to obtain delay information various timing delay models were developed. However general survey of most of these timing delay …


A Pc Based Computer Model With A Postprocessor For The Movement Of Groundwater, Joseph Byra Dec 1990

A Pc Based Computer Model With A Postprocessor For The Movement Of Groundwater, Joseph Byra

Theses

Currently available computer programs that model groundwater flow are inherently limited in their capabilities, in one way or another. Additionally, many of these computer programs are relatively inaccessible to the general user because they operate off of mainframe computers and sophisticated plotters. As a result, a simple to use computer program called 2DFLOW has been modified so it can be run on a personal IBM compatible computer. It models steady-state fluid flow through saturated porous media. In addition, a postprocessor called 2DPLOT has been developed. The postprocessor generates the equipotential contours and the flux vectors that describe the physics of …


Digital Correlators For Spread Spectrum Communications, Raymond B. Chadwick Dec 1990

Digital Correlators For Spread Spectrum Communications, Raymond B. Chadwick

Theses

The design and application, in spread spectrum communications, of a digital correlator implemented in a Xilinx Field Programmable Gate Array is presented. Spread spectrum communications, correlators and Xilinx Field Programmable Gate Arrays are first introduced. A digital correlator is designed and implemented in a Xilinx Field Programmable Gate Array. Cascading correlators to increase the correlation dimensions is next explored. The maximum operating frequency of the digital correlator is calculated and simulated to be 40 Mhz; a significant speed improvement over commercially available correlators such as those from TRW.


Molecular Modeling Studies Of Anatoxin Agonist Analogues, Qizhan Yao Dec 1990

Molecular Modeling Studies Of Anatoxin Agonist Analogues, Qizhan Yao

Theses

Thirty two anatoxin agonist analogues were investigated by means of computerassisted molecular modeling studies to delinate factors that may contribute to potency. The structures were generated from the fragment libraries from the SYBYL program, and minimized by the MM2 program. Then a systematic conformational search was done based on the global minimized structures to get bioactive conformations.

Ten agonists were further studied after the conformation optimization. The most potent agonists among these analogues, (+)-anatoxin-a (11), about 300 times as potent as carbamylcholine, severed as a template for the rest to examine the superimposability of the hydrogen bonding acceptor site and …


A Study Of Machining Parameters To Optimize Surface Finish In Metal Cutting Through Cnc, S. Waseem H. Zaidi Dec 1990

A Study Of Machining Parameters To Optimize Surface Finish In Metal Cutting Through Cnc, S. Waseem H. Zaidi

Theses

The purpose of this thesis is to find the relationship between surface finish and machining parameters. A series of experiments have been performed at shop floor of NJIT, on MAZAK(CNC turning center), using two different cutting tool materials(high speed steel and cemented carbide) and a workpiece of Aluminium. The results have been then evaluated and analyzed to see the effects of various combinations of cutting conditions, that is, feed, speed, and depth of cut. Recommendations have been made on the basis of analysis to estimate the minimum and maximum values of surface roughness with respect to the cutting conditions for …


An Investigation Of Optoelectronic Integrated Circuit Receiver, Dinar S. Gupte Dec 1990

An Investigation Of Optoelectronic Integrated Circuit Receiver, Dinar S. Gupte

Theses

This thesis report presents an investigation of an OptoElectronic Integrated receiver Circuit (OEIC). An OEIC on Silicon (Si) substrate is analyzed and simulated as part of this investigation. The OEIC is based on GaAs technology. The advantages of this are its compactness, high speed, low noise and high reliability in light wave communication systems. A higher output signal is required to make such devices suitable for practical applications. This is achieved by the use of a cascode stage. The fabrication techniques of the relevant semiconductor devices have also been discussed.

In light wave communication systems, the region of minimum losses …


Design And Development Of Ccd Camera For Document Scanner Using Optical Fiber Bundle, Aniruddha P. Joshi Dec 1990

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 …


Analysis Of Field Distribution Of A Dielectric Resonator And Its Applications, Manohar R. Kamath Dec 1990

Analysis Of Field Distribution Of A Dielectric Resonator And Its Applications, Manohar R. Kamath

Theses

Dielectric resonators (DR) are suitably shaped objects made of high dielectric constant materials like TiO2, BaO, ZnO, and accessory ingredients, which can function as electrical resonators covering a very wide frequency range upto 40GHz. The physical dimensions of dielectric resonators are in mm range. High dielectric constant material resonators seem to be ideally suited for microwave applications because of their miniature size, low loss, insensitivity to magnetic dc biasing fields, and ability to concentrate large RF magnetic fields in small volumes. However temperature stabilization of dielectric resonators is an important consideration as the center frequency is a function …


Slotted Aloha Protocol For Packet Transmission Via Satellite Link : Throughput Performance Of Continuous Transmission Packet, Solon Karashialis Dec 1990

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 …


Performance Evaluation Of Extended Token Ring Network Under Message Priorities, Prakash B. Kukadia Dec 1990

Performance Evaluation Of Extended Token Ring Network Under Message Priorities, Prakash B. Kukadia

Theses

Local Area Networks carrying multiple priority classes of messages have received considerable attention recently. A simulation model of a symmetric, priority based network, consisting of token ring networks interconnected by a bridge is implemented. Messages are divided into two priority classes, namely, high priority classes and low priority classes. Two different approaches are considered for transmission of high priority messages. [1] Each station transmits the same amount of high priority traffic when the token reaches the station, regardless of the time elapsed from previous token arrival. [2] The amount of high priority traffic transmitted by each station may vary at …


An Integrated Circuit X-Ray Sensing Array Based On A Cmos Flip-Flop Cell, Huan-Chung Lee Dec 1990

An Integrated Circuit X-Ray Sensing Array Based On A Cmos Flip-Flop Cell, Huan-Chung Lee

Theses

A novel X-ray sensor IC has beeli designed which counts individual photons at rates up to 5,000,000 counts per second. A two-dimensional X-ray flip-flop sensor array, consisting of an 30 x 30 matrix of CMOS flip-flop sensors integrated in one chip together with an internal clock generator and access selection circuitry is described. A flip-flop sensing cell contains cross-coupled CMOS devices, one of which is connected to a large-area reverse-biased diode. A large area diode exposed to X-ray flux triggers the flip-flop. By reading out the final stable state of the flip-flop, the absence or presence of an X-ray photon …


The Dewaterability Of Anaerobically-Digested Sludges, Hui-Ching Lee Dec 1990

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 …


Evaluation Of Rates Constants In An Isothermal Turbular Reactor, Yu-Hsin Lin Dec 1990

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, Κb for the homogeneous reaction and Κω 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 Dec 1990

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,zGaiAs photodiodes with x > 0.53 is its response to higher wavelengths than the standard lattice-matched photodiodes. An InxGa1-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 In0.88Ga0.12As photodiodes is presented. Dark current analysis, which is a critical parameter in photodiodes, …


Optimization On Isdn In Multihop Radio Networks Through Genetic Algorithm, Prashant H. Pahade Dec 1990

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 Dec 1990

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 …


Electromagnetic Transients Program Interfacing, Enhancement And Comparison With Spice, Siswa Trihadi Dec 1990

Electromagnetic Transients Program Interfacing, Enhancement And Comparison With Spice, Siswa Trihadi

Theses

The Electromagnetic Transients Program (EMTP) is a computer program used to simulate high speed power system transients. The EMTP input data structures and the rules in setting up the input data file are described in this thesis by means of two sample cases i.e an RLC series circuit and a sin le line to ground fault in power system.

The EMTP input data are very detailed an highly-structured column-dependent. To improve the user-friendliness of EMTP by ignoring the difficulty of arranging the column structures, this thesis presents the EM P User Interactive Program. Sample cases using this interactive program are …


Electrical Measurements Of Mos Structures Fabricated On Etched Silicon Surfaces, Venkata Ramana Vankayalapati Dec 1990

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 Dec 1990

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 …


Finite Element Analysis Of Torsional Concentric Composite Shaft Using Isoparametric Circular Element, Yee-Haur Wong Dec 1990

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 …