Engineering Commons^™

Microprocessor-Based Closed-Loop Control, Man T. Chan

Retrospective Theses and Dissertations

Microprocessor-Based Closed-Loop Motor Control. A dedicated microprocessor control system was built from chip level using the Motorola M6800 family. The system has a keyboard and the interfaces for four LED displays, a phototransistor and a digital-to-analog converter. The system accepts key input in RPM and drives the motor at the input RPM with display of the real RPM updated approximately every second.

Study Of Virtual Memory, Shridhar S. Dixit

Retrospective Theses and Dissertations

This research report gives a general description of virtual memory systems. The mechanisms and policies and their effect on the operation and efficiency of virtual memory are explained. A virtual memory using a real time virtual address decoder, to decode a 32 bits of virtual address for the secondary memory to obtain the primary address location discussed. The decoder is developed with the use of associative or content-addressable memories. Replacement algorithms, used for selecting the pages of the main memory to be replaced, are described. The hardware implementation of the least recently used and least often used replacement policies using …

Test 1430: Ford 6610 And 6710 (16x4) Diesel 8 And 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …

Computer Driven Training Simulator Of Wastewater Treatment Operations, G. Robert Silkenson

Retrospective Theses and Dissertations

This research involves design and implementation of computer program for simulation of a wastewater treatment plant. The program has the capability to be interfaced with an existing analog wastewater plant process flow training board which is equipped with meter readouts of key process variables and adjustable control valves. It is planned that the total system simulator could be used to train wastewater treatment plant operators to afford them hands-on dynamic experience in plant operations. The wastewater treatment process modeled is the activated sludge process. Beginning with the known plant design stead-state equations for this particular process an algorithm was developed …

Closed Water Systems On Paper And Board Machines Using The Dysco Simulation Program, Stephen Robert Tremont

Masters Theses

This study was conducted to determine the accuracy of the DYSCO simulation program in simulating the open and closed water system on the pilot fourdrinier paper machine located in the Department of Paper Science and Engineering at Western Michigan University. The pilot machine was run at a maximum speed of 76 meters (250 feet) per minute without the press and drier sections, as well as slower speeds of 61 and 46 meters per minute. Retention data were obtained for fiber, titanium dioxide, and water at the three speeds. Upon entering these data along with stream inputs into the DYSCO simulator, …

H & V News : 21st Anniversary Issue

Building Services Engineering

No abstract provided.

Evaluation Of The Utah Operational Weather Modification Program, Geoffrey E. Hill

Reports

This study is an evaluation of a winter orographic cloud seeding project in Utah. The evaluation is based upon both intensive field measurements and historic~l records. For the field measurements, ground and airborne data were collected during February and March, 1981 in the vicinity of the Tushar Mountains. In evaluating the physical data three aspects are emphasized: the dispersal of artificial ice nuclei, the distribution of supercooled liquid water, and the growth and trajectories of precipitation. Ground based measurements were made by K and X band radars, a dual frequency microwave radiometer, a network of precipitation gauges, an ice nucleus …

Improved Finite Element Methodology For Integrated Thermal-Structural Analysis, Pramote Dechaumphai

Mechanical & Aerospace Engineering Theses & Dissertations

An integrated thermal-structural finite element approach for efficient coupling of thermal and structural analysis is presented. New thermal finite elements which yield exact nodal and element temperatures for one-dimensional linear steady-state heat transfer problems are developed. A nodeless variable formulation is used to establish improved thermal finite elements for one-dimensional nonlinear transient and two-dimensional linear transient heat transfer problems. The thermal finite elements provide detailed temperature distributions without using additional element nodes and permit a common discretization with lower order congruent structural finite elements. The accuracy of the integrated approach is evaluated by comparisons with analytical solutions and conventional finite …

Experimental Investigation Of A Direct Expansion Solar-Assisted Heat Pump, James Yau-Jwo Shen

Mechanical & Aerospace Engineering Theses & Dissertations

A direct expansion solar-assisted heat pump, which uses economical bare solar collectors as evaporator, is designed and operated. The experimental results indicate that marked improvement in thermal performance results if the collector/ evaporator temperature is maintained at o0c to 10°c above the ambient temperature. During the course of this investigation, the system thermal performance is determined under various ambient and operating conditions by measuring the incident solar energy flux, refrigerant flow rate, temperature and pressure at various locations in the system. The heat pump coefficient of thermal performance and solar collector efficiency ranging from 2.0 to 3.0 and 40% to …

A Pattern Analysis Algorithm For Wind Ambiguity Removal, Jaime R. Tormos

Electrical & Computer Engineering Theses & Dissertations

Some remote sensing devices, such as satellite microwave scatterometers, produce sampled wind vectors that are accurate in speed and streamline direction, but have a directional ambiguity of 180°. The extraction of information from the two dimensional wind vectors is readily handled using pattern analysis techniques. It is shown that there is sufficient information in the spatial relationships of the generated windstream vectors to recognize the driving meteorological wind patterns. This then leads to the resolution of the wind ambiguity problem. This thesis presents the development of a pattern analysis algorithm that generates a measure of the raw data set that …

Bulletin - March, 1982, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

A twelve page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.

Seasat-Satellite Investigation Of The Structure Of Western Nebraska And Its Application To The Evaluation Of Geothermal Resources, John Stix

United States Department of Energy: Publications

Seasat synthetic aperture radar (SAR) satellite imagery was used to interpret the structural framework and, indirectly, the geothermal potential of an area in western Nebraska. Lineaments were mapped from the imagery and then compared to known structure. It was found that Seasat does record surface manifestations of subtle basement structures, particularly faults and joints. Furthermore, two areas with hot dry rock geothermal potential were delineated using Seasat and other data. It is stressed that more subsurface geology and geophysical data are needed before a final evaluation of the geothermal potential can be made. Seasat imagery is a useful reconnaissance exploration …

Energy In Agriculture: Requirements For Farm Use Of Solar Energy In Kentucky, Richard S. Hiatt

Agricultural Engineering Energy Series

There is increasing interest in utilizing solar energy to supplement heating and grain drying energy needs on the farm, Many Kentucky farmers realize that their demands for heat and the orientation of certain buildings on their farms suggest solar heating potential. But most farmers are not familiar with the requirements and limitations of solar heating.

This publication discusses those factors a farmer must consider when evaluating the solar potential of agricultural structures on the farm. Solar requirements are divided into two main areas: (1) site requirements associated with the building and its surroundings and (2) load requirements associated with the …

Factors Influencing The Production Rate And Quality Of Lead Sinter, John R. Knoepke, Hung Yang Tsai, Arthur E. Morris

Materials Science and Engineering Faculty Research & Creative Works

The sintering characteristics of a typical Missouri lead concentrate were determined for two types of raw sinter mix: conventionally prepared and pelletized. The important sintering characteristics are sulfur elimination, sinter strength, production rate of sinter, permeability of the sinter bed, and bed temperature. These characteristics were analyzed statistically, and are described by an empirical model, in which proportion of returns, moisture content, air flow, bed height, size distribution of returns, and ignition time are the independent variables. The characteristics of a conventionally prepared sinter mix are most strongly affected by the moisture content of the raw mix. The characteristics of …

Polynomial Approximations To Mooring Forces In Equations Of Low-Frequency Vessel Motions, Bohdan W. Oppenheim, P. A. Wilson

Systems Engineering Faculty Works

Multivariate polynomial approximations are considered to the coupled nonlinear mooring forces acting on a vessel moored with multileg moorings. The objective is to yield explicit forms of equations of the low-frequency vessel motions, since the exact mooring forces are known numerically only. Such forms could then be used for analytical solutions of the equations of motion. It is shown that the polynomials lack sufficient generality and accuracy for this purpose, and hence solution of the problem can be considered only by the exact method.

Efficient Infrared Upconversion In Gap, M. A. Gundersen, T. A. Yocom, P. G. Snyder, P. F. Williams

P. F. (Paul Frazer) Williams Publications

Mechanisms for linear conversion of infrared to visible were investigated in extrinsic Gap. Efficient (1 %) conversion of 10 micron to visible was observed in GaP:Zn,O. Several device applications are discussed and a quantum counter scheme involving 111-V photocathodes is presented.

H & V News

Building Services Engineering

No abstract provided.

Constant-Psi Constant-Delta Contour Maps: Applications To Ellipsometry And To Reflection-Type Optical Devices, A.-R. M. Zaghloul, R. M.A. Azzam

Electrical Engineering Faculty Publications

Constant-psi constant-delta contour maps in the reduced angle-of-incidence-film-thickness plane that are useful in ellipsometry and in design of reflection-type optical devices are discussed. As a specific example, a contour map is given for the SiO₂-Si film-substrate system at the 6328-Å He-Ne laser wavelength.

Seismic Design For Buildings, Department Of The Army, The Navy, And The Air Force

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

This updated manual with revised seismic design provisions governs the design and construction of Army, Navy, and Air Force facilities and supersedes the April 1973 issue. Basic criteria are stated herein with augmentations and clarifications of the criteria. Also, commentary and design examples are included to provide comprehensive applications and guidelines for the seismic-resistant design of facilities. The organization of the manual has been revised to present the topics in a more orderly manner. The dynamic analysis approach for seismic design is not covered but its use is not precluded in this manual.

The basic criteria cited are the "Recommended …

Simple Powerful Tunable Single-Mode And Mode-Locked Tea Co2 Laser, R. A. Dougal, M. A. Gunderson, P. F. Williams

P. F. (Paul Frazer) Williams Publications

A simple method for constructing a single longitudinal-mode CO₂ laser that is tunable within individual rotational transitions is presented. Useful power levels, typically 0.3 J per pulse in a single-mode beam, are obtained from a single-stage device. Mode-locked output can also be obtained from the laser. In addition, design and construction of a local oscillator for making absolute in situ frequency measurements is described.

Studies Of Computer Mediated Communications Systems : A Synthesis Of The Findings, Computerized Conferencing & Communications Center, Starr Roxanne Hiltz, Elaine B. Kerr

Computerized Conferencing and Communications Center Reports

This report is an attempt to collect and synthesize current knowledge about computer-mediated communication systems. It focuses on computerized conferencing systems, for which most evaluational studies have been conducted, and also includes those electronic mail and office support systems for which evaluative information is available. It was made possible only through the participation of the many systems designers and evaluators listed below, who took the time to help to build a common conceptual framework and report their findings in terms of that common framework.

Structural Stability Research Council: Proceedings 1982, Structural Stability Research Council

CCFSS Library (1939 - present)

One of the purposes of the the of Council is to maintain a forum where the the of Council is to maintain a forum where the structural stability aspects of metal andcomposite metal and concrete structures and and their components can be presented for evaluation, and pertinent structural research problems proposed for investigation. The Annual Technical Session provides an opportunity to carry out this function.

Metal Cation/Anion Speciation Via Paired-Ion, Reversed Phase Hplc With Refractive Index And/Or Inductively Coupled Plasma Emission Spectroscopic Detection Methods, Richard N. Savage, D. Bushee, I. S. Krull, S. B. Smith, Jr.

Materials Engineering

Conventional high performance liquid chromatography instrumentation and packing materials can be inexpensively and rapidly utilized for the qualitative and quantitative analysis of various metal cations or anions. The final approaches utilize reversed phase HPLC in the form of paired-ion separations. The detection of individually eluted, fully resolved metal cations or anions is possible via conventional refractive index or inductively coupled plasma emission spectroscopic detection. In many cases, unresolved mixtures of metal cations, eluted as a single peak on HPLC, can be resolved and identified via the use of ICP detection. Both metal cations and anions can be easily resolved, according …

Geotechnical Evaluation Of The Support Of Coal Pillars In Underground Coal Mines., John D. Rockaway, Richard W. Stephenson

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Study Described Was Accomplished through an Investigation of Both the Intact and Insitu Geotechnical Properties of the Sub coal Strata and through the Installation of Floor Movement Monitoring Instrumentation. the Method of Bearing Capacity Analysis Developed by A. S. Vesic Was Used to Define Pillar Stability. This Method Includes Provisions for Taking into Consideration a Two-Layer System Such as Assumed for Mine Conditions Where a Weak Underclay overlies Firmer Strata.

Grab Samplers For Benthic Macroinvertebrates In The Lower Mississippi River, C. Rex Bingham, David B. Mathis, Larry G. Sanders, Eva Mclemore

United States Army: Publications

Data from 24 grab samples, eight each taken with the Standard Ponar, Petite Ponar, and Shipek grabs from a backwater habitat were statistically compared using one-way analysis of variance. Total grabs produced 5696 organisms and 24 distinct taxa. Results showed no difference in catch efficiency among grab samplers for distinct taxa, total densities, and densities of the dominant taxa: Lirceus sp., Ilyodrilus templetoni, Hexagenia sp., Limnodrilus cervix, Limnodrilus hoffmeisteri, Sphaerium sp., and immature Ilyodrilus. The Petite Ponar grab captured significantly fewer immature Limnodrilus. This was attributed to clumped distribution of these worms rather than difference …

Vegetative Delineation Of Coastal Salt Marsh Boundaries, H. Peter Eilers, Alan Taylor, William Sanville

United States Environmental Protection Agency: Publications

Two decades of intensive research following the suggestions of Odum (1961) and the work of Teal (1962) have firmly established positive values for undisturbed coastal salt marshes. These intertidal wetlands are noted for high macrophyte production and for export of energy-rich organic detritus and dissolved organic carbon to estuarine waters. They serve as juvenile fish and wildlife habitats, water purifiers, and buffers to erosion of sediment.

Plastic Deformation And Fracture Of Binary And Ternary Aluminum Alloys Under Compressive Loading, Samir Mokhtar Biblawi

Archived Theses and Dissertations

No abstract provided.

Bacterial Mosaic: A New Corynebacterial Disease Of Wheat, Randall R. Carlson, Anne K. Vidaver

Biological Process Development Facility: Staff Publications

Bacterial mosaic is a foliar disease of wheat; characteristic symptoms are small yellow lesions, more or less uniformly distributed over the leaf. It was discovered in Nebraska in the spring of 1976. By 1979, the pathogen was distributed over an 800-km range and had been isolated from 16 cultivars of winter wheat. The pathogen is Corynebacterium michiganense subsp. tessellarius, a Gram-positive coryneform. Wheat was the only host that showed symptoms after inoculation. The pathogen reached high population levels (> 10⁶ colony-forming units per gram of fresh weight) without apparent symptoms in tomato and in six of nine gramineous …

Pressure Drop Across A Restriction Of Annular Geometry, Farshid Yarizadeh

Retrospective Theses and Dissertations

This report presents experimental results for the pressure drop across a restriction of annular geometry used in a typical pressurized water reactor steam generator. The pressure drops were obtained for air, water, and the corresponding two-phase mixtures.

The loss coefficients associated with these pressure drops were experimentally determined and empirical relations correlating the results were developed.

The tests were performed at atmospheric conditions (atmospheric temperature and pressure), and the two-phase flow mass velocity ranged from 236 to 711 1bm/s-ft².

A Computer Method To Evaluate The Vibration Response Of Stiffened Floor Systems To Impact Load, Michael E. Donahue

Retrospective Theses and Dissertations

Composite construction of floor systems with steel joist or I-beam stiffeners supporting a concrete slab have a tendency to sustain perceptible vibration due to small impacts. An engineering design aid, utilizing a small micro-computer and a BASIC computer program, was developed to analyze rectangular floor systems for susceptibility to sustain vibrations perceptible to humans. The analytical method for the normal modes of vibration using the Rayleigh-Ritz method and the superposition of the normal mode response is derived. A vibration index is calculated to qualitatively rate the floor. The computer method was validated using published data for an I-beam supported concrete …