Digital Commons Network^™

Feed Drive Design For Numerically Controlled Machine Tools, Subash Bhatia

Masters Theses

"The various types of feed drive control systems used in numerical control of machine tools have been broadly classified. Further a step by step design has been presented for the feed drive of a numerical contouring control milling machine. The aim has been to develop a consistent strategy for tackling a variety of such problems. Consequently stress has been laid on principles and not on design figures"--Abstract, page ii.

Frequency Division Using Cascaded Phase-Locked Loops, Curtis B. Abshier

Masters Theses

"In many practical communication systems it is necessary to generate phase coherent subharmonics of an input tone. A useful system for accomplishing this task is a system of phase-locked loops in cascade. It is shown that when the feed-forward function is matched, the phase error of the second loop is zero. Analytical analysis and computer simulation prove that the minimum time to achieve phase-lock is obtained when the feed-forward function is matched. Under this condition, necessary design parameters are determined with ease"--Abstract, page i.

Design Of A Quadrature Envelope And Correlating Receiver, Clinton Harold Moor

Masters Theses

"A receiver design analysis and rationale is presented. The receiver is capable of performing in an instrumentation role for propagation experiments conducted in the field. The data gathered during the field tests will be used to determine the complex impulse response of the ground-to-ground communications channel and to evaluate the performance of a candidate ranging waveform in this channel. The receiver is capable of operation in either the propagation mode or the ranging mode and each mode of operation can be performed on either a UHF band frequency or an L-Band frequency. During the propagation mode the receiver serves as …

An Analysis Of Solar Noise Outbursts And Their Application To Space Communication, Marion Francis Moen

Masters Theses

"A relationship between sunspot activity, solar flare activity and noise outbursts is presented. Five different types of interference radiation in the 10MH_z to 30,000 MH_z frequency band are discussed. Data obtained by solar radio astronomy are analyzed to determine the extent of solar noise outbursts as a function of sunspot activity. An application of the burst data to future space communication is given"--Abstract, page ii.

Variable-Threshold-Mixed-Weight Threshold Element, Cheng-Chung Liu

Masters Theses

"A threshold element (TE) is a mathematical model of a class of logic gates. The desirability of a threshold element in the application of digital systems stems from its richness of logic power and its relative economy. On the other hand, the tighter tolerences required by the threshold logic element as compared to conventional logic gates have prevented them from being utilized extensively. The purpose of this thesis is to propose a versatile threshold element having high noise immunity and loose tolerance requirement. The proposed TE which has variable threshold and mixed weight capability uses current switching to enhance noise …

An Analog Computer Simulation Of The Flapping Of A Helicopter Hinged Main Rotor Blade, Edward Charles Robinson

Masters Theses

"An analog computer simulation was performed on the Systron Donner SD 40/80 electronic differential analyzer consisting of one panel (SD 40) less three modules augmented by three digital logic modules for iterative operation. The flapping equation was solved in continuous iteration for various values of blade mass and the resultant blade flapping magnitudes and harmonic coefficients were compared in computer plots of the blade tip path plane. A flap compensator was added and the result plotted. Various aerodynamic parameters of the flapping equation solution were plotted"--Abstract, page ii.

A Time And Frequency Domain Approach To The Optimization Of Linear Multivariable Regulators, Eugene Charles Machacek

Masters Theses

"Optimal design and analysis of a multivariable regulator may be achieved in either the frequency or time domain. This paper describes the formulation of the matrix Riccati equation in the time domain and the Wiener-Hopf equation and the root-square-locus in the frequency domain. The necessary requirements which must be satisfied in order to achieve an optimal control vector when using a quadratic performance index are presented for both domains. The resultant optimal control vector is shown to be a linear function of the system state vector. The effect of the quadratic performance index weighting matrices on the optimal system closed-loop …

A Closed Form Method For Predicting The History Of Circular Orbit Altitude Decay Of A Near-Earth Satellite Including The Effect Of A Dynamic Atmosphere, John Copley Buchholtz

Masters Theses

"A closed form expression for the time to decay between two circular orbit altitudes is developed. The long-term dynamic variation of high altitude atmospheric density is included. The density is approximated as a ratio of two quadratics with the numerator being a function of the time-related exospheric temperature and the denominator being a function of altitude. The 11-year cyclic variation of exospheric temperature is then represented as a piecewise linear function of time. The analytic expression for circular orbit altitude decay rate is developed by describing the energy loss due to atmospheric drag. A point mass representation of the Earth's …

An Investigation Of Stress In The Monowall Construction System Subjected To Racking Loads, Louis Alex Kuhlmann

Masters Theses

"Several methods of analysis were employed to investigate the stress conditions of concrete block built in the MONOWALL Construction System, when subjected to racking loads. MONOWALL is a technique of assembling blocks with adhesive rather than conventional portland cement mortar. The analyses used in this study included strain gages on full-scale walls, photoelastic models, and a mathematical solution. Each method of analysis is reported separately in detail and the results compared to each other"--Abstract, page ii.

Perturbation And Sensitivity Analysis Of An Urban Model, Nicola Ann Nelson

Masters Theses

"This work describes a sensitivity analysis of the nine major system variables of the urban model postulated by Dr. Jay W. Forrester in his book Urban Dynamics. This model simulates the growth of a city from a nearly empty land area through a 250 year life cycle. Using small perturbations about the system trajectories, sensitivity matrices were computed at 135 years (growth period) and 240 years (equilibrium). The results show a matrix heavily weighted to give large sensitivity coefficients to the three housing variables, the PH sector being the most sensitive. Each of the housing sectors was analyzed further to …

A Digital Computer Simulation Of A Rural Two-Lane Highway, D. Jay Frankenfield

Masters Theses

"The traffic flow model developed in this study is a digital computer simulation utilizing the technique of periodic scanning to move the vehicles through a series of unit blocks. The model simulates traffic flow on a rural two-lane highway by assuming a straight and level road and incorporating sight distance restrictions and no-passing zones to simulate the effect of limited sight distance. By utilizing various "passing rules" to initiate the passing maneuver, three general topics were investigated. This study investigated the use of 1000 ADT as a criterion for yellow line striping no-passing by using the computer simulation to determine …

A System Study Of A Computerized Grocery Store, Neal Joseph Martini

Masters Theses

"This thesis is a system study of a computer controlled grocery store. Previous work has been done in the area of computerized inventory control, and computerized checkout lines in grocery stores, but the system proposed in this thesis is to control the movement and handling of the products as orders are automatically filled. In the preliminary part of the system study, a comparison between a time shared computer service and a minicomputer is done, which results in the selection of a minicomputer for this control system. Then the general control system is presented, and the system interfacing and control for …

Compressibility Effects On Transient Gas Pipe Flow, Gerald Francis Mouser

Masters Theses

"Abstract (1) Methods of iterative solution for the partial-differential equations that govern the transient flow of gases in pipelines are obtained by using the method of characteristics and linear finite-difference techniques. Solutions are developed for 1) a constant gas compressibility factor throughout transient conditions, and 2) a variable gas compressibility factor at constant temperature dependent upon pressures encountered during transient flow. Theoretical studies are made to compare results using both approaches for pipelines operating at various constant flowing temperatures. Results show greater differences between the two methods at lower values of flowing temperature due to the more rapidly changing compressibility …

Laser Interferometric Holography Investigation Of Free Convection About A Vertical Plate Of Non-Uniform Temperature, Richard Kenneth Thomson

Masters Theses

"An experimental investigation was conducted using a holographic interferometer to detect the temperature variation in a free convection boundary layer about a vertical heated plate. The heated plate was non-isothermal and investigations were conducted for four temperature distributions; the maximum plate temperature ranged from 200F to 493F. Photographs were taken of the fringe patterns and boundary layer thickness measurements, as well as temperature measurements, were made. A theoretical model was constructed by applying the integral method to the energy and momentum equations. The experimental values agree quite well with this model. The advantages of the holographic interferometer over other systems …

An Empirical Method Of Correlating Compressibility Factors Of Nitrogen - Helium - Hydrocarbon Systems, Terry Wayne Buck

Masters Theses

"Compressibility factors have been taken from previous works by Davis and Taneja for twelve different common oil-field hydrocarbon mixtures which contain at least 2 mole % nitrogen. An effort has been made to show that by using the Benedict-Webb-Rubin Equation of State it is possible to predict compressibility factors using a correlation of error in predicted compressibility factor versus reduced pressure, at different mole % of nitrogen with constant reduced temperatures, if the critical points of the mixtures are known or can be calculated. In the mixtures which contain helium, the only effect of helium seems to be the raising …

Development Of An Elastic-Plastic Finite Element Program With The Initial Strain Approach, Vernon Dale Allen

Masters Theses

"A finite element method is presented for solution of plane stress and axisymmetric elastic-plastic problems employing the method of successive elastic solutions with the initial strain approach. The problem of nonconvergence of the initial strain approach for perfectly plastic problems was eliminated by expressing the Prandtl-Ruess equations entirely in terms of strain. Two examples are presented to demonstrate the validity of the method"--Abstract, page ii.

Analysis Of Factors Affecting Station Capacitor Bank Switching Transients, M. Davarpanah

Masters Theses

"The problem presented here is a study using a computer program which predicts the transient response when energizing a station capacitor bank of a power system. The computer program gives the wave shape and magnitudes of switching surges obtained while energized capacitor banks at one location and showing the effect of switching a bank while adjacent banks are already energized. The over voltages are given in line-to-ground voltages on the line side of the capacitor banks as well as at lower voltage levels down to the customer 120 volts service voltages. The purposes are to obtain the optimum values of …

The Use Of Semiconductor Memories In Drug Dispensing, James John De Largy

Masters Theses

"This paper presents the problems encountered and the methods used during the design of an electronic system to be an integral part of a medical drug dispensing machine. The system has a memory composed of both random access and read only memories to enable it to operate, along with many such machines , from one data input line. The system accepts information such as patient's name, social security number, and drug location number. It also provides signal drive to an attached printer in order to reproduce this information for use on the drug label. Finally, the system electronics accepts input …

The Effect Of Skip-Grading On Stability Of Soil-Aggregate Mixtures., Asif Faiz

JTRP Technical Reports

No abstract provided.

Practical Optimization Of Steel Highway Bridge Beams., Robert Henry Busek

JTRP Technical Reports

No abstract provided.

Optimization Of The Structural Design Of Asphalt Pavements : Technical Paper, Joseph C. Oppenlander, Salim Said Hejal, L. D. Burns

JTRP Technical Reports

No abstract provided.

An Evaluation Of Traffic Signal Coordination, Conway Edward Cooper

JTRP Technical Reports

No abstract provided.

The Prediction Of Running Speeds On Urban Arterial Streets, Kenneth Alan Shackman

JTRP Technical Reports

No abstract provided.

Travel Time And Accident Benefits Due To Reconstruction Of U.S. 52 Bypass At Lafayette, Indiana : Progress Report, Alexander Edward Mcneil

JTRP Technical Reports

No abstract provided.

Mechanical Methods Of Steel Placement For The Slipform Construction Of Continuously Reinforced Concrete Pavements : Technical Paper, Charles F. Scholer, Olubayo Timothy Olateju

JTRP Technical Reports

No abstract provided.

Water Conservation Handbook, D J. Carder, G. W. Spencer

Natural resources published reports

This handbook is intended as a practical guide in some of the most common aspects of water conservation in the agricultural areas of Western Australia. It deals mainly with water conserved in dams for stock and domestic purposes on the farm.

the farm. The handbook does not attempt to deal with all aspects of handling and using water for agricultural purposes. This is a vast subject which extends into many fields such as engineering, irrigation and land use.

The guide does, however, touch on some important aspects of good management of agricultural land. It should be read in conjunction with …

A Generalized Investigation Of Potentially Poor Soil Support By Regional Geomorphic Units Within The Adjacent 48 States : Preprint, Matthew W. Witczak, C. W. Lovell

JTRP Technical Reports

No abstract provided.

Techniques In Slipform Paving And Continuously Reinforced Concrete Pavement Construction, Olubayo Timothy Olateju

JTRP Technical Reports

No abstract provided.

Driver Information Systems For Highway-Railway Grade Crossings, Thomas Urbanik

JTRP Technical Reports

No abstract provided.

Young Drivers' Severe Automobile Accidents : Progress Report, William Asher, Michelle Shapiro

JTRP Technical Reports

No abstract provided.