Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 190261 - 190290 of 196433

Full-Text Articles in Engineering

Anodic Oxidation Of Pure And D.S. (Dispersion Hardened) Lead In Sulfuric Acid Solutions, Rafael San Martin Aldazabal Jan 1969

Anodic Oxidation Of Pure And D.S. (Dispersion Hardened) Lead In Sulfuric Acid Solutions, Rafael San Martin Aldazabal

Masters Theses

"The anodic oxidation of pure and dispersion hardened lead in 1 N H₂SO₄ was studied potentiostatically in the range - 0.28 to 2.0 volts (SHE). The anode surfaces were observed at various stages on a scanning electron microscope and x-ray diffraction techniques were used to determine the phases present. It was established that by oxidation up to 0.25 v only PbSO₄ is obtained. At potentials between 0.25 and 1.57 v, PbO (tetragonal) is formed beneath the lead sulfate layer. At potentials above 1.57 up to 2.0 v, a layer of ßPbO₂ forms in the outermost part of the anode underlying …

Go to article

An Investigation Of Transient Negative Resistance In A Cadmium Sulfide Device, John Irvin Giem Jan 1969

An Investigation Of Transient Negative Resistance In A Cadmium Sulfide Device, John Irvin Giem

Masters Theses

"An analysis has been made of a CdS device which exhibits a transient negative resistance at room temperature and low field strengths whereas previously reported cases of negative resistance in CdS were observed at low temperatures and moderate to high electric fields. The CdS bar was illuminated on one end in the vicinity of an ohmic In contact. Contact was made to the other end of the device with a rectifying Ag contact and the device was reverse biased. Experimental evidence and the analytical results both indicated that it is necessary that the material used to make the negative resistance …

Go to article

Solution Of The Two-Dimensional Multigroup Neutron Diffusion Equation By A Synthesis Method, William Ray Heldenbrand Jan 1969

Solution Of The Two-Dimensional Multigroup Neutron Diffusion Equation By A Synthesis Method, William Ray Heldenbrand

Masters Theses

"A method, called the higher mode synthesis method, for the solution of the two-dimensional neutron diffusion equation is developed. In this method, the two-dimensional eigenfunction is expanded in terms of one-dimensional fundamental and higher eigenfunctions. A substitute, weight, and integration procedure is applied and the two-dimensional equation is reduced to a one-dimensional equation in terms of expansion coefficients. The expansion coefficients are combined with the trial functions in order to obtain the two-dimensional eigenfunction. This procedure results in a significant reduction of computation time as compared with standard iteration methods"--Abstract, page ii.

Go to article

The Design Of Three-Port Strip Line Circulator, Jeng Seng Chang Jan 1969

The Design Of Three-Port Strip Line Circulator, Jeng Seng Chang

Masters Theses

"This dissertation is concerned with the analysis and design of the radius of ferrite disk of strip line circulator using a generalized analytical field expression. The first part consists of an analysis of the field in the ferrite disk with the TEM wave incident normally on the air-ferrite boundary. It is approximated by taking the boundary condition at the incident and outlet points, so that analytical expressions for the electric and magnetic fields can be obtained. The next part consists of an approximate method to determine the radius of the ferrite disk based on the result obtained in the first …

Go to article

Method For Optimizing Multi-Layer Insulation, William Donald Morath Jan 1969

Method For Optimizing Multi-Layer Insulation, William Donald Morath

Masters Theses

"The use of multi-layer insulation can result in reduced material cost, weight, or volume. A method for selecting layer materials is described. Each layer material is selected to operate at its upper temperature limit and to contribute to the overall performance of the wall. The analyses required for optimizing flat and cylindrical walls are developed. Use of the digital computer makes it feasable [sic] to select layer materials from a large group of candidates. Fortran IV programs for optimizing flat and cylindrical walls are presented, and their use is demonstrated by the solution of example problems. Methods for improving the …

Go to article

Design Of R-C-C-R Spatial Mechanism, Kao-Chien Hsei Jan 1969

Design Of R-C-C-R Spatial Mechanism, Kao-Chien Hsei

Masters Theses

"An analysis to design a particular R-C-C-R spatial mechanism was developed using tensor notations and operations. This specific R-C-C-R spatial mechanism can be used to couple two shafts intersected at a skew angle with constant rotating speed ratio. This skew angle, or bending angle of the two shaft, may vary from 30 up to 180 degrees. The governing equations of relative positions of the mechanism were formulated as a function of two variables: the bending angle of the shafts and the rotating angle of the input link. To exemplify the various design conditions, the design parameter versus the bending angle …

Go to article

Precipitation Hardening Of A Mg - 3.5 Wt. % Th - 1. Wt. % Mn Alloy, Adolf Chun-Chiung Huang Jan 1969

Precipitation Hardening Of A Mg - 3.5 Wt. % Th - 1. Wt. % Mn Alloy, Adolf Chun-Chiung Huang

Masters Theses

"The precipitation process in a Mg - 3.5 wt. % Th - 1. wt. % Mn alloy during aging at 260⁰, 350⁰ and 400⁰C was determined principally by transmission electron microscopy. At 350⁰ and 400⁰C, general precipitation of the equilibrium Mg₄Th phase moderately hardens the alloy. No transition lattice of this phase was seen. The Mg₄Th precipitate forms initially as disc shaped plates parallel either to the prism or basal plane of the matrix...During prolonged aging at 400⁰C the plates lengthen into long laths on either of the above planes in the close packed direction...At 260⁰C an unidentified G. P. …

Go to article

Establishment Of A Torsion Pendulum And Its Evaluation, Ashwin Kantilal Ghatalia Jan 1969

Establishment Of A Torsion Pendulum And Its Evaluation, Ashwin Kantilal Ghatalia

Masters Theses

"A torsion pendulum apparatus has been constructed. The pendulum has been evaluated by studying the Zener relaxation in α brass. Three wire specimens of commercial alloy of Cu-Zn were used and the value of log decrement has been obtained by the method of free decay of the oscillations. The known Zener peak was observed"--Abstract, page ii.

Go to article

An Analysis Of An Audio Amplifier Utilizing An Operational Amplifier And Negative Feedback, Anthony Francis Lexa Jan 1969

An Analysis Of An Audio Amplifier Utilizing An Operational Amplifier And Negative Feedback, Anthony Francis Lexa

Masters Theses

"An audio amplifier utilizing a monolithic operational amplifier is analyzed. The analysis is a block diagram approach where the amplifier is divided into three parts; operational amplifier, power amplifier, and feedback network. A Fourier series analysis is used to describe the distortion and signal components of the amplifier output. The results of this analysis demonstrate the advantage of large negative feedback on frequency response and harmonic distortion. Using relatively few passive components a high quality audio amplifier is constructed with an output power of 15 watts RMS power and negligible harmonic distortion"--Abstract, page ii.

Go to article

Analysis Of A Water Level Control, Bhupendra Girdharlal Shah Jan 1969

Analysis Of A Water Level Control, Bhupendra Girdharlal Shah

Masters Theses

"This thesis presents the analysis of a controller for a liquid level control system. The controller was built using an analog computer providing the ability to easily construct up to three modes of control. The controllers analyzed were: 1.) Proportional, 2.) Proportional plus reset, and 3.) Proportional plus reset plus preact. The system was tuned experimentally to provide satisfactory operation and root loci were also plotted to show the system stability for the three modes"--Abstract, page ii.

Go to article

Calculation Of Optimum Conditions For Simultaneous Heat And Mass Transfer In Porous Membranes, Chia-Chang Liu Jan 1969

Calculation Of Optimum Conditions For Simultaneous Heat And Mass Transfer In Porous Membranes, Chia-Chang Liu

Masters Theses

"The object of this investigation was to study desalination using evaporation through porous membranes and to estimate the economic potential of the method. The major factors affecting the economics were: 1. The saline water temperature into the evaporator, tsl; 2. the temperature driving force in the evaporator, DF; 3. the temperature driving force in the heat exchanger, DTEX; and 4. the saline water temperature leaving the evaporator, ts2. The optimum conditions based on cost of water product were studied by calculating water costs under a wide range of conditions. for any given set of variables t …

Go to article

Film Boiling From Inclined Flat Surfaces, Charles Ernest Price Jan 1969

Film Boiling From Inclined Flat Surfaces, Charles Ernest Price

Masters Theses

"The object of this investigation was to determine the effect of inclination on the heat transfer for saturated film pool boiling from a flat plate heater. Nitrogen at atmospheric pressure was used as the test fluid. The test plate was oriented at various angles from the horizontal position and the convective film coefficient was determined for each angle. Tests were conducted for heater angles of 0°, 30°, 60°, and 90°. The heater strip was placed in a container of the liquid and was heated electrically. Heat transfer results were obtained for plate temperatures ranging from 100 to 800°F. As the …

Go to article

Nuclear Parameter Study In One, Two, And Three Dimensions, Jan Robert Lojek Jan 1969

Nuclear Parameter Study In One, Two, And Three Dimensions, Jan Robert Lojek

Masters Theses

"A parameter study comparing one-, two-, and three-dimensional reactor design analyses was undertaken. Computer programs (codes) were used extensively for the computations and running times on the IBM 360/50 were observed. The values of primary concern were neutron flux shapes, effective multiplication factors, and fuel depletion. Dresden I nuclear power plant with fuel type 1 represents the model reactor. Cross section calculations were performed using the nuclear codes HRG and TEMPEST II, FEVER, EXTERMINATOR-2, AND FLARE generated the nuclear parameters"--Abstract, page ii.

Go to article

A Study Of Different Types Of Connections To Structural-Steel Square Tubings, Chao-Sheng Chen Jan 1969

A Study Of Different Types Of Connections To Structural-Steel Square Tubings, Chao-Sheng Chen

Masters Theses

"Although square tubular element has long been recognized as an ideal structural member, its acceptance was limited by the lack of detailed knowledge on suitable connections related to this geometric shape. It is structurally inefficient to use a strong column poorly connected to a strong beam. So it is necessary to understand, in advance of adoption, the effect and behavior of different types of connections and to develop an efficient structural system. In this study, the ordinary column-to-beam framing with different types of connections has been investigated. The three types of connections are single-plate connection, double-angle connection, and multi-angle connection. …

Go to article

Thermal Fatigue Testing Of Die Casting Die Steels, Kulwant Singh Sabharwal Jan 1969

Thermal Fatigue Testing Of Die Casting Die Steels, Kulwant Singh Sabharwal

Masters Theses

"Thermal fatigue is a form of surface failure produced by repeated thermal stresses and is the main cause of die retirement in the die casting industry. A general review of the fundamental and practical aspects of thermal fatigue as encountered in the dies, based on earlier published work, is given and preliminary experiments in an effort to set up a suitable method of testing to study this phenomenon are then described. In the present technique developed to create the thermal conditions experienced by a die steel in aluminum die casting, a small portion of one face of a cylindrical test-piece …

Go to article

Static And Dynamic Instability Analysis Of Rigid Frames With Timoshenko Members, Carlton Lee Smith Jan 1969

Static And Dynamic Instability Analysis Of Rigid Frames With Timoshenko Members, Carlton Lee Smith

Masters Theses

"In this thesis, a technique has been developed to determine the natural frequencies of plane rigid frames with the consideration bending, shear deformation, rotatory inertia, and internal axial forces. The internal forces are functions of the instability load of the vibrating system for which the effects of bending and shear deformation on the stability of this structure are considered. For the sake of completeness, the matrix formulations for the dynamic or stability analysis of a rigid frame are given. The stiffness matrices of these formulations are then derived. The influence of shear deformation, rotatory inertia, and internal axial force is …

Go to article

Further Investigation Of The Traveling-Wave Transistor, Robert J. Feugate Jan 1969

Further Investigation Of The Traveling-Wave Transistor, Robert J. Feugate

Masters Theses

"A brief introduction to the concept of a traveling-wave field-effect transistor is presented. Analytic solutions for certain lossless and lossy special cases are derived and a numerical method for solution of the general case developed. A possible computer program for implementing this numerically is given and utilized to compare the traveling-wave transistor to a conventional field-effect transistor amplifier"--Abstract, page ii.

Go to article

Numerical Simulation Of Pressures In A Radical System, Vijender Nath Gopal Jan 1969

Numerical Simulation Of Pressures In A Radical System, Vijender Nath Gopal

Masters Theses

"The time-space location of an advancing front has been described in such a manner as to permit the calculation of frontal pressures when a heterogeneous (in permeability) radial system is subjected to water encroachment. A finite difference application has been developed to calculate these pressures at specified radial distances from the injection or production wellbore. These pressure have been further utilized to predict the pressures at the advancing front for different time intervals"--Abstract, page iii.

Go to article

A Computerized Method For Finding The Dynamic Response Of Multi-Mass Systems With Damping To Arbitrary Inputs, Bakulesh Balbhadra Patel Jan 1969

A Computerized Method For Finding The Dynamic Response Of Multi-Mass Systems With Damping To Arbitrary Inputs, Bakulesh Balbhadra Patel

Masters Theses

"A practical procedure for the systematic application of Foss's method to the solution of multi-degree-of-freedom damped systems is presented. It is relatively easy to determine the response of classically damped systems to various inputs. For non-classically damped systems the method proposed by K. A. Foss has been employed. This method gives an exact and complete solution for the response of linear multi-mass damped systems subjected to arbitrary inputs. Since the method requires lengthy and complex computations, the use of a digital computer is essential. In order to obtain the complete response of a multi-mass damped system to both sinusoidal and …

Go to article

Vibration Of An Internally Damped Tapered Truncated Cantilever Beam, Chimanbhai Magandas Patel Jan 1969

Vibration Of An Internally Damped Tapered Truncated Cantilever Beam, Chimanbhai Magandas Patel

Masters Theses

"This thesis provides a vibration analysis of an internally damped, tapered, truncated, cantilever beam. Using two formulations of the problem based on: (1) Discrete mass and (2) continuous mass distribution, solutions are given for a beam having square cross section with linear depth and linear width variation. A Kelvin viscoelastic material for the beam is assumed. The vibration of the beam is considered to produce plane stress in the material, and the stress-strain relationship is applied only to the strain in the plane of bending. An exact solution for frequency of oscillation, mode shape, and steady state response is obtained …

Go to article

Fast Neutron Effects On Transistor Scattering Parameters, David Leslie Gray Jan 1969

Fast Neutron Effects On Transistor Scattering Parameters, David Leslie Gray

Masters Theses

"It has not been possible in the past to characterize a transistor or other semiconductor device with regard to its performance in a fast neutron (E>10keV) environment when the device is operated at high (>100 MHz) frequencies. Using the scattering (s-) parameter concept, which regards a device as a two-port "black box", a full characterization of the trends in the neutron bombarded high-frequency performance of a typical transistor can be made. Scattering parameters are not only an accurate means of describing the high-frequency performance of any device, but are now reasonably easily measured with the advent on the …

Go to article

Neutron Induced Changes To The Modified Ebers-Moll Transistor Model Used In The Net-1 Program, Kenneth Robert Smith Jan 1969

Neutron Induced Changes To The Modified Ebers-Moll Transistor Model Used In The Net-1 Program, Kenneth Robert Smith

Masters Theses

"The development of theoretical and empirical relations which predict the permanent changes to the electrical characteristics of silicon transistors is described in this paper. Analytical techniques are also developed to obtain the parameters used in the Modified Ebers-Moll transistor model. The method employed is to determine the effects on externally measurable characteristics and to relate these changes to the parameters in the Modified Ebers-Moll transistor model. Further, all nonlinear characteristics are related to the independent variables with interpolating polynomials and degraded characteristics presented. then degraded characteristics are used to establish the parameters for and parameter changes to the transistor model …

Go to article

A Study Of The Effect Of Tube Bundle Geometry On The Nucleate Boiling Region Of A Series Of Hydrocarbon Liquids, Robert Terry Montgomery Jan 1969

A Study Of The Effect Of Tube Bundle Geometry On The Nucleate Boiling Region Of A Series Of Hydrocarbon Liquids, Robert Terry Montgomery

Masters Theses

"The primary purpose of this heat transfer investigation was to determine quantitatively in what manner tube bundle geometry affects the nucleate boiling region of a tube whose single tube boiling characteristics are known. A series of tests were conducted with horizontal tube bundles which produced boiling in a saturated pool of n-hexane, n-pentane, and seven carbon (C₇) hydrocarbon mixture at atmospheric pressure. Tube bundle size and pitch were the principle independent variables considered. The phenomena of heater hysteresis and aging were also studied. Data are presented which indicates that aging probably is not a direct consequence of gas adsorption on …

Go to article

The Effect Of Aging On The Exfoliation Corrosion Characteristics Of 7178 Aluminum Alloy, J. James Slavick Jan 1969

The Effect Of Aging On The Exfoliation Corrosion Characteristics Of 7178 Aluminum Alloy, J. James Slavick

Masters Theses

"The objective of this investigation was twofold: 1) to determine the effect of the quench-to-artificial aging delay period on the exfoliation corrosion of 7178 aluminum alloy subsequently aged at 250F for 24 hours and 2) to determine the effect of an initial aging treatment at 212F on the tensile properties and exfoliation of 7178 aluminum subsequently aged at 250F. Testing was conducted on 0.125 inch thick sheet. Quench-to-aging delay periods of 0 to 28 days, and initial artificial aging treatments at 212F for 24 and 48 hours were investigated. In addition, the effect of overaging T6 material at 320F for …

Go to article

Tunnel Diode Models For Electronic Circuit Analysis Program (Ecap), Carmon Dale Thiems Jan 1969

Tunnel Diode Models For Electronic Circuit Analysis Program (Ecap), Carmon Dale Thiems

Masters Theses

"In this paper ECAP models for the tunnel diode are presented. Results showing the model, the current-voltage charateristics [sic] are discussed. Operation in typical circuits is presented. A summary of the current state of the art in modeling appears in Appendix I. Since ECAP is only structured to accept piecewise-linear models of these devices, that type of model is presented here. All of the models are developed to approximate the typical tunnel diode current-voltage characteristic"--Introduction, page 1.

Go to article

A Synthesis Procedure Of Distributed Rc Parameter Networks, Chun-Ming Wen Jan 1969

A Synthesis Procedure Of Distributed Rc Parameter Networks, Chun-Ming Wen

Masters Theses

"Synthesis procedures for driving-point functions and transfer functions in the w plane are developed in this thesis. For driving-point functions and transfer functions which are single-valued in s, where s is the complex frequency variable, the synthesis procedures were derived from the extension of the O'Shea's trasformation [sic]. For the transfer functions which satisfy the stability theorem in the w plane, a synthesis procedure is developed by using a distributed-lag element (DL) or a uniform distributed RC (UDRC) network with matched terminations"--Abstract, page ii.

Go to article

A Photoelastic Study Of The Stresses Around An Underground Opening And Its Support System, Alphonse C. Van Besien Jan 1969

A Photoelastic Study Of The Stresses Around An Underground Opening And Its Support System, Alphonse C. Van Besien

Masters Theses

"The stress conditions around openings in rock have long been of interest to the field of rock mechanics. The purpose of this investigation was to determine the stress distribution around an opening with a rib and wall-plate support system. A photoelastic model of the opening (a modified horse-shoe section) was loaded in the centrifuge to determine the effect of body loading. Both the tangential stress and the stress within the rock bench, due to the opening, were determined. The stress conditions within the bench were examined using simulated ribs and a loading frame. Application of the data is discussed, as …

Go to article

A Study Of Low-Cost Heat Exchangers For Desalination, Chin-Tsai Lin Jan 1969

A Study Of Low-Cost Heat Exchangers For Desalination, Chin-Tsai Lin

Masters Theses

"This investigation was proposed to search for simple and inexpensive but effective heat exchangers for the recovery of heat in water desalination by evaporation through non-wettable porous membranes. Aluminum was chosen as the material for constructing the heat exchangers. Various fluted arrangements and one plate type arrangement were chosen to increase heat transfer coefficients and conserve material. Equations correlating the heat transfer coefficients to temperatures and flow rates have been suggested for estimating the overall heat transfer coefficient at different conditions. The results of economic calculations indicate that the cost per unit transfer area of the exchangers in this investigation …

Go to article

A Study On Load Transfer Of Model Friction Piles, Richard Milton Franke Jan 1969

A Study On Load Transfer Of Model Friction Piles, Richard Milton Franke

Masters Theses

"Previous investigations concerned with disturbance of soft clay by driving displacement piles are summarized. The initiation of excess pore water pressures due to pile driving, and mechanisms of load transfer are also described, along with the applicapability of model pile testing in analysis of the various phenomena. Load tests were conducted on assorted sizes of model friction piles embedded in sedimented soil samples with consisted of a silt and clay mixture. Pilot holes of various diameters were cut in the samples. A theoretical load distribution curve was used to calculate the load transferred to the soil as a function of …

Go to article

Design And Use Of A Universal Logic Circuit, Mahendrakumar Punjalal Shah Jan 1969

Design And Use Of A Universal Logic Circuit, Mahendrakumar Punjalal Shah

Masters Theses

"Yau and Tang have designed universal logic circuits (ULC's) of three variables with 8 I/O pins. They assumed that only one variable was available as a free input variable in its true and complementary form, the others were available as fixed input variables and the circuit generated true and complementary outputs. Their design required 22 I/O pins for a four-variable ULC, constructed from three variables ULCs. This paper decrived [sic] an algorithm for determining the input-pin connections, directly from the K-map of a given output function, for any n-variable ULC. Forslund and Waxman have designed a three-variable ULC using the …

Go to article

First Prev Next Last