Engineering Commons^™

The Effect Of Recycle Control On Activated Sludge Clarification Efficiency, Joseph A. Margio

Retrospective Theses and Dissertations

Recent advances in activated sludge facilities operations utilize sludge recycle flow rate control to minimize adverse effects on the clarifier during peak solids loading situations. Although this control action is directed at the thickening function, there has been speculation that the elevated recycle rates may be responsible for an increased effluent solids concentration. To evaluate the significance of recycle rate to the steady-state effluent suspended solids concentration, identical side-by-side settling columns were operated with recycle rates spanning the range of normal practice. The studies were conducted so that each side-by-side unit received identical activated sludge feed slurries. Replicate experimental units …

Survey Of Fiber Optic Connectors And Cables, John B. Ostlund

Retrospective Theses and Dissertations

Today the world of fiber optics is bigger than ever. What is available to the engineer and the technician is now only apparent to the well informed. Not all engineers and technicians have a background or an education in the field of fiber optics. This report is intended to be an informative preliminary guide to those readers whose interest lies in the field of fiber optics.

The advantages of fiber optic systems are discussed and compared to conventional systems. Although a fiber optic system includes transmitters and receivers, this report concentrates primarily on fiber optic connectors and cables. It also …

Model For A Nonlinear Tank System Under Proportional-Integral-Derivative Control, Charles W. Bishop

Retrospective Theses and Dissertations

A model (NONLINRK) was developed for a closed tank system under feedback control by an ideal proportional-integral-derivative controller. Under servo action the fluid level in the tank is altered from its equilibrium set point. Under regulatory action the feed pressure to the inlet valve and/or the outlet valve percentage opening are varied from equilibrium settings. The numerical model uses Gill’s fourth-order Runge-Kutta algorithm to solve the system equation. The equation was made separable by approximating an exponential factor by the tangent at the beginning of each time step in the numerical solution. NONLINRK simulation trials exhibited many characteristics of linear …

A Computer Graphics Head-Up Display For Air-To-Air And Air-To-Ground Flight Simulation, Daryl R. Mair

Retrospective Theses and Dissertations

A computer graphics simulation of an aircraft Head-Up Display was designed using an RDS-3000 Ikonas Graphics Processor and a PDP-11/34 host computer system. The software control and display modules were accomplished using Ikonas microcode and Digital Equipment Corporation Fortran IV-PLUS. The Head-Up Display system consists of the basic flight data, which includes aerodynamic flight information, Roll/Pitch Ladder, and the Velocity Vector or Flight Path Marker. The system was designed for flexibility in modifications and evaluation of various weapons delivery systems. These will be adapted to specific needs by research scientists and engineers at the Visual Technology Research Simulator in Orlando, …

Design And Analysis Of A 4ghz Low Noise Amplifier, Abdulla I. Al-Rawahy

Retrospective Theses and Dissertations

The Gallium Arsenide Field Effect transistor (GaAs FET) is experiencing a widespread acceptance in space and terrestrial systems due to its low noise, high gain and frequency characteristics unmatched by bipolar devices. This paper describes a design of a 4 GHz low noise amplifier with GaAs FETs using the scattering parameters method. Special attention is given to overall noise/gain optimization in the band of interest. The Smith Chart is used extensively to match the two-port device with microstrip networks. Analysis and performance of the amplifier are presented.

Use Of The Ada Language System In Configuration Control Of Fortran-Based Software, Daniel L. Dyke

Retrospective Theses and Dissertations

The Configuration Control and Management of Trainer Systems Software has been recognized as a significant problem for many years. Many software tools are being developed for use as aids in this task. The efforts of the Department of Defense in the development of Ada and an Ada Programming Support Environment (APSE) have strongly addressed the problems of configuration control and management. However, these efforts have been targeted for Ada-based software as it is anticipated it will be the primary language of the DOD. The author feels that FORTRAN based software will require maintenance for many years even after the acceptance …

An Algorithm For Computing Fast, Accurate, Z-Plane Root Locus Plots, David R. Jahn

Retrospective Theses and Dissertations

Root locus analysis/synthesis is an extremely powerful tool used in classical control system design. Its results can be used to check stability, speed of response, and system damping. However, the solutions to root locus problems can be extremely difficult to obtain in digital control system because the poles are in close proximity. Optimized algorithms will be presented which circumvent this problem and allow for fast, accurate z-plane root locus plots. Prompting for data entry, minimum memory in-place computations, and very little processing requirements yield an easy to use, highly efficient program.

Design Considerations For A Digital Audio Equalizer, Timothy Young

Retrospective Theses and Dissertations

The objective of this thesis is to consider a method for designing a digital audio equalizer. The primary design criteria is minimum audible frequency response error between a digital and a "reference" analog equalizer throughout the entire audio frequency range from 20 Hz to 20 Khz. The first step is to obtain a set of analog filters that suitably represent the reference equalization. From these filters, digital filter coefficients are generated using the bilinear transformation. Then, the digital filters are combined with anti-aliasing and D/A reconstruction filters and a zero-order hold to complete the design. Analysis of methods to minimize …

Digital Signal Processing Capabilities Of The Fujitsu Mb8764, Harold B. Creech

Retrospective Theses and Dissertations

The Fujitsu MB8764 digital signal processing chip is designed to operate with a machine cycle of up to 10 MHz. The chip’s ability to perform a 16-by-16 bit multiply and add operation in one machine cycle makes it a good candidate for real time digital signal processing. Unlike the Intel 2920 the Fujitsu MB8764 does not have an onboard analog-to-digital, digital-to-analog converter. Therefore, this paper will be restricted to the operation of this device with digital data input and output. The use of the MB8764 as a digital filter is analyzed. Performance limitations due to finite word length, memory size …

Computerized Displacement Data Analysis In Laser Speckle Photography, Bijan Chitsaz

Retrospective Theses and Dissertations

Laser speckle photography is an experimental technique which provides a non-contract means for direct measurement of in-plane displacements of objects subjected to different loading conditions. It requires a camera system to record two images of the object that are illuminated with laser light on a high resolution film. The double-exposure film (specklegram) is a permanent record of the displacement information of the object. Point-by-point analysis of the specklegram will yield the displacement data, but requires considerable time to complete the data reduction. An automated data analysis system is developed and described in this report. He-Ne laser and computer-controlled translation stages …

Evaluation Of Miramat Under High Velocity Flows, C. Earl Israelsen, Frank W. Haws

Reports

Introduction: Newly constructed earth channels and steep cut and fill slopes on construction projects need temporary protection from water erosion until a protective cover of vegetation can be grown. In some instances the temporary protective measures can be left in position to serve as part of the permanent system. Various kinds of vegetative and chemical mulches are available for use as temporary control measures, and other materials such as jute, fiberglass roving, and excelsior blanket are also in use. However, for large volumes of flow and for high velocities, more substantial materials are required. One class of such materials is …

The Effect Of Electrodes On The Thermally Stimulated Currents In Sodium Silicate Glass, Ruth Mogrovejo Cuzmar

Masters Theses

“Electrodes play an important role in the study of alkali ion motion in glasses when TSPC/TSDC techniques are used. Silver, gold and combinations of them were used in the study of Na⁺ motion in Na₂O·3SIO₂ glass. The lower temperature peak is not affected by any of these electrodes, so it is attributed to the bulk glass. A second and third peak are strongly dependent on the kind of electrode used. A gold anode is a blocking electrode, and a gold cathode, is partially blocking. There is a tendency for a space charge polarization to form when …

Sintering Of Catio₃ With The Addition Of Caco₃ And Lif, Surapol Pleekram

Masters Theses

"The densification of CaTiO₃ with the addition of 4.74, 5.90, 6.88 mol% CaCO₃ and 22 mol% LiF was investigated over the temperature range 800° to 1050°C, for sintering times ranging from 1 to 216 hours. It was found that CaCO₃ reacts with LiF and to form a liquid at a temperature of about 450°C. This liquid enhances the densification of CaTiO₃ . The densification process was followed by making weight loss, shrinkage and porosity measurements. The microstructural development was determined by scanning electron microscope examination of both fractured and polished surfaces. X-ray diffraction and DTA/TGA were …

An Evaluation Of Magnetic Field Shielding And Cross Talk For Various Cable Configurations, Amir Hossein Nafar

Masters Theses

"The effect of shield grounding on magnetic field coupling in coaxial and twisted pair cables, was studied for various positions of the ground connection at 50 KHz. For the case of only one end of shield grounded the attenuation was about 60 dB. Furthermore, the effect of frequency from 50-500 KHz was considered on three cases. Thus it was concluded that attenuation increases as frequency increases. A combined experimental and analytical investigation was also conducted to characterize the mechanism of cross talk between wires of ribbon cable and traces on printed circuit boards. Inductive and capacitive coupling were studied in …

The Effect Of The Degree Of Saturation On The Permeability Of A Compacted Clay To Organic Permeants, Mark Alan Harms

Masters Theses

"Relationships for permeability of kaolinite versus degree of saturation and permeability versus flow are developed for 0.005 N calcium sulphate, xylene and aniline permeants using the triaxial flexible wall permeameter. The clay was statically compacted at degrees of saturation of 50%, 75% and 100%. A gradient of 277 was used for the permeability tests.

The initial degree of saturation was inversely related to the permeability of the clay. Saturated clay samples were found to be virtually impervious to aniline and xylene. As the degree of saturation decreased, the permeability increased with the initial volume of flow equivalent to the volume …

Speed Report No. 118 : Interim Report, C. J. Oliva, Robert M. Shanteau, George K. Stafford, Leroy Gray

JTRP Technical Reports

No abstract provided.

Embark-Telar-Surfactant-2, 4-D Combination For Vegetation Management Along Indiana Roadsides : Interim Summary Report, D. James Morré

JTRP Technical Reports

No abstract provided.

Development Of An Energy Audit Manual For Indiana Department Of Highway Buildings, Brett Michael Partridge

JTRP Technical Reports

No abstract provided.

Systematic Analysis Of Noninferior Transfer Assignments, J. R. Wright, Steven Christian Egly, H. W. Gallivan

JTRP Technical Reports

No abstract provided.

Effects Of Endomycorrhizal Inoculation On Growth Of Selected Landscape Plants Used In Highway Revegetation, Stephen Dunning Verkade, Philip L. Carpenter

JTRP Technical Reports

No abstract provided.

The Identification Of Areas Of Routine Maintenance Productivity Improvement, Stephen M. O'Brien, Kumares C. Sinha

JTRP Technical Reports

No abstract provided.

Stabl5: The Spencer Method Of Slices, James Richard Carpenter

JTRP Technical Reports

No abstract provided.

The Use Of Fuzzy Sets Mathematics To Assist Pavement Evaluation And Management, Manol Andonyadis, A. G. Altschaeffl, Jean-Lou Chameau

JTRP Technical Reports

No abstract provided.

Compressibility And Shear Strength Characteristics Of Impact Compacted Lacustrine Clay : Informational Report, Samuel Onyeabor Nwabuoekei

JTRP Technical Reports

No abstract provided.

Rigid Pavement Pumping: (1) Subbase Erosion And (2) Economic Modeling : Informational Report, Wijk Adriaan Van

JTRP Technical Reports

No abstract provided.

Behavior Of Mucks And Amorphous Peats As Embankment Foundations : Interim Report, Paul Gerard Joseph

JTRP Technical Reports

No abstract provided.

Evaluation Of Low Temperature Properties Of Gas Oil, Dina Atef Abd El Ghaffar

Archived Theses and Dissertations

No abstract provided.

Seabrook: A Case Study In Mismanagement, Irvin C. Bupp

New England Journal of Public Policy

The Seabrook nuclear power plant construction project is an unqualified financial disaster. It simultaneously threatens its chief owner, the Public Service Co. of New Hampshire (PSNH) with bankruptcy and the company's electricity customers with huge rate increases. The fifteen-year history of the project is reviewed to identify "what went wrong?"

The review suggests that the basic problem has been mismanagement by both PSNH and by government regulators. A three-year regulatory imbroglio over the environmental effects of the plant's cooling system was extremely costly in the mid-1970s.

By the time this problem was belatedly resolved, the project had begun to outstrip …

1985 Directory Of Indiana State, County, City And Town Officials Responsible For Road And Street Work, Herpicc

Indiana Local Technical Assistance Program (LTAP) Directory

Contact information for agency officials and employees responsible for Indiana’s local road infrastructure.

Writing A Scientific Paper Prior To The Research, Charles F. Babbs, Martha M. Tacker

Weldon School of Biomedical Engineering Faculty Publications

The traditional approach to preparing a research report for publication is to begin writing after the study has been completed. We propose another approach- to write a "zeroth" draft before the study is begun. This approach helps to focus the investigator's attention during the planning stage on critical aspects of the study. The discipline of writing down the rationale, the methods, and the variety of possible outcomes and their significance helps to clarify the logic on which the study is based. If these are acceptable to all authors and colleagues in the zeroth draft, it is likely that the research …