Engineering Commons^™

Low Temperature Lattice Parameters And Expansion Coefficients Of Ai2au And Lif Gruneisen Constants Of Lif, Martin E. Straumanis, Jayant S. Shah

Materials Science and Engineering Faculty Research & Creative Works

There is no difference in the thermal expansion behavior of an intermetallic compound (Al2Au) and of an ionic (LiF), except in the magnitude of the expansion coefficients, which for both compounds upon cooling below 40°K approach zero. The lattice parameters of the two compounds mentioned decrease uniformly and without anomalies with lowering the temperature, approaching a constant value below 40°K. The a–T relationship between 40 and 180° is given in form of equations. A pump working on the Joule‐Thomson principle was used for cooling. The GRÜNEISEN parameter, γ, of LiF between 40 and 180°K is a constant, contrary to theoretical …

Thermal Expansion Behavior Of Silicon At Low Temperatures, Jayant S. Shah, Martin E. Straumanis

Materials Science and Engineering Faculty Research & Creative Works

Lattice parameters, thermal expansion coefficients and Grüneisen parameters of silicon are determined by an X-Ray diffraction method in the temperature range of 180-40 K without the use of liquid gases. Thermal expansion of silicon becomes negative below 120 K which is discussed in terms of its lattice vibrations and crystal structure. © 1972.

Comment On The Nature Of The Disaccommodation In Hcp Co-C Alloys, J. Keiser, Manfred Wuttig

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Polynary Telluride Glasses Containing Silver, H. E. Anthonis, N. J. Kreidl

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Pbo Transformation Induced By Water, Charles A. Sorrell

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.

Effects Of Cold Working Under Pressure On Subsequent Yield, J. G. Hoeg, Robert L. Davis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A method utilizing high pressure fluid environments is described whereby a three-dimensional subsequent yield surface was determined for 304 stainless steel cylindrical parent specimens of this material were prestrained in axial compression under fluid pressure and then small sub specimens were sectioned from these parent specimens. Finite element techniques were used to optimize the parent specimen size so that a zone of uniform axial stress woidd result during the prestraining. Longitudinal strains in this zone were monitored during the prestraining and the subspecimens were cut from this region in a manner that did not allow the machining to appreciably affect …

Minimum Distance Classification In Remote Sensing, A. G. Wacker, D. A. Landgrebe

LARS Technical Reports

The utilization of minimum distance classification methods in remote sensing problems, such as crop species identification, is considered. Minimum distance classifiers belong to a family of classifiers referred to as sample classifiers. In such classifiers the items that are classified are groups of measurement vectors (e.g. all measurement vectors from an agricultural field), rather than individual vectors as in more conventional vector classifiers.

Specifically in minimum distance classification a sample (i.e. group of vectors) is classified into the class whose known or estimated distribution most closely resembles the estimated distribution of the sample to be classified. The measure of resemblance …

Minimum Weight Design Of Stiffened Cylindrical Shells Using Structural Synthesis, Joseph Eugene Heckelbeck

Retrospective Theses and Dissertations

Several search methods for unconstrained minimization in the minimum weight design of a stiffened cylindrical shell are investigated. The cylindrical shell, under study, is stiffened with bar shaped stiffeners in the longitudinal and circumferential directions, and capable of being loaded both axially and radially with up to ten separate load conditions. For this investigation, it was necessary to alter an unconstrained minimization program for use on the IBM 360 computer by employing double precision techniques. The computer runs obtained on this system are compared with those provided by the prior work of William Morrow and Lucien Schmit. The results show, …

An Automated Student Advisement And Projected Course Enrollments, Brian Odell Montgomery

Retrospective Theses and Dissertations

One of the major problems of the modern university is the process of student advisement and course scheduling. The purpose of this paper is to write a computer program which will aid in solving this problem of student advisement and course scheduling for the undergraduate students of the College of Engineering at Florida Technological University. the computer program which is developed in this paper, aids in the problem of student advisement by producing a one page output for each student. This output page, which is separated by department, lists all courses the student has taken and passed, all transfer hours, …

Factors Influencing Dehardening And Rehardening Of Forsythia X Intermedia Stems : Progress Report No. 4, David Foster Hamilton

JTRP Technical Reports

No abstract provided.

Evaluation Of Transition Curves On Two-Lane Rural Highways, Robert Walter Lyford

JTRP Technical Reports

No abstract provided.

Procedure Manual For Determining Traffic Patterns For A Simplified Planning Procedure For Major Thoroughfare Planning In Small Urban Areas : Interim Report, Andrew Delaney Jones, William Louise Grecco

JTRP Technical Reports

No abstract provided.

Improvement Of Kentucky Bluegrass Through Selection And Breeding, William Hugh Daniel

JTRP Technical Reports

No abstract provided.

Treatment Of Sanitary Wastes At Interstate Highway Rest Areas, Phase I, James E. Etzel, David W. Hawkins, Kwang Myeung Cho

JTRP Technical Reports

No abstract provided.

Computerized Slope Stability: A Sliding Block Model, Aditya Mohan

JTRP Technical Reports

No abstract provided.

A Simplified Procedure For Major Thoroughfare Planning In Small Urban Areas, Andrew Delaney Jones, William Louise Grecco

JTRP Technical Reports

No abstract provided.

Factors Influencing Dehardening And Rehardening Of Forsythia X Intermedia Stems : Technical Paper, David Foster Hamilton

JTRP Technical Reports

No abstract provided.

An Analytical Study Of A Confined Viscous Vortex, David Edward Crow

Doctoral Dissertations

"A composite solution for the flow field of a three dimensional, incompressible laminar, viscous vortex confined inside a conical converging nozzle is presented. This model is used to study the strong mainstream boundary layer interaction that occurs in confined vortex flows. The confined vortex flow field is divided into mainstream and boundary layer regions. A particular class of solutions of the general equations of motion is used to represent the vortex flow in the mainstream region. That is, the tangential velocity in the mainstream region is assumed to be of the form W = T(e)/R. Velocity and pressure profiles from …

The Use Of Shaped Explosive Charges To Investigate Permeability, Penetration, And Fracture Formation In Coal, Dolomite And Plexiglas, Calvin J. Konya

Doctoral Dissertations

"The concentration of methane gas which exists in the exhaust air from a coal mine is critical. It can be controlled by dilution of the gas with fresh air or by the regulation of the rate of methane emission into the mine workings. Degasification techniques which control the emission rate are currently being developed. The use of shaped charges to initiate fractures in coal and increase the gas flow rate was the object of this research. The three areas of investigation were: 1) permeability changes in coal models after fracturing with shaped charge jets, 2) fracture formation in coal and …

The Electrochemical Reduction Of Fumaric Acid On Hg-Bi Cathodes, Chen Hwei Chi

Doctoral Dissertations

"The electrochemical reduction of fumaric acid was studied on Hg, Hg/1%Bi amalgam, and Bi at 60ºC in acidic solutions of various pH ranging from 0.3 to 3.7. The fumaric acid was reduced to succinic acid with high efficiency on each electrode. The steady state kinetic parameters included Tafel slopes of ca. 2.3 RT/F and first order concentration dependences for both undissociated fumaric acid and H⁺. Transient measurements indicated low coverages of adsorbed fumaric acid and no adsorbed hydrogen species in the potential region of the reaction. A reaction mechanism is proposed which involves a chemical rate determining step between an …

Probabilistic Models For Construction Estimating And Bidding, James E. Spooner

Doctoral Dissertations

"Two probabilistic models are offered as a means for quantitatively determining contingency in a lump-sum bid. The first model is based on the isolated project and requires subjective evaluation of probabilities associated with the individual elements of the estimate. Contingency is defined as a function of the standard deviation of project field costs. Procedures are developed to obtain the variance of the total field cost from three-value estimates of the primary quantities. The second model considers the business as a stochastic process with an initial risk reserve and a positive risk loading, and contingency in this model is a function …

Modal Truncation Of Substructures Used In Vibration Analysis, Suresh Kumar Tolani

Doctoral Dissertations

"The objective of this study is to describe in a unified manner a group of structural dynamics analyses using the substructures technique. An additional effort is to provide a consistent basis for the selection of substructure principal modes as required by this method. Substructure principal mode frequency roots and strain energy are two criteria evaluated for the selection of substructure principal modes. System eigenvalues and system strain energy are investigated for the comparison of results in the principal modes. System strain energy should provide more rational results since it is proportional to the stress times the strain in the system …

The Effect And Compensation Of Time-Base Perturbations In Analog Recording Systems, Clifford D. Skouby

Doctoral Dissertations

"The mean square error between recorded and reproduced signals is used as an error measure to determine the effects of time-base perturbations on an analog singal. The mean square error caused by time-base perturbations is shown to be proportional to the product of the square of the signal bandwidth and the time-base error variance for the case of low pass signal. When the signal is band pass, there is shown to be an additional error term which is proportional to the square of the signal center frequency and the time-base error variance.

Calculations are also carried out to determine the …

A Learning Receiver For Communication In Three-Component Multipath Channels, Richard Paul Brueggemann

Doctoral Dissertations

"An adaptive receiver is designed for transmissions through a time-varying multipath channel which may include both specular and diffuse components. The design is based on the theory of unsupervised learning machines and the receiver is a recursive structure which does not grow in complexity with each new observation, but is Bayes' optimal at each instant of time. The multipath medium is modelled as an aggregate of L conditionally independent transmission paths, each consisting of random and/or fixed reflections, and is identified in terms of three components: (1) indirect diffuse scatter, (2) indirect specular reflection, and (3) direct transmission. The channel …

Iicads--Integrated Interactive Computer Aided Design System, Archie Golden Lambert

Doctoral Dissertations

"This research has three goals. The first goal is to develop a software interface (supervisor) to support and control a variety of interactive subsystem modules; thus eliminating manual scheduling of interactive jobs. The second goal is to develop a common methodology for interactive subsystem design. The third goal is to develop a linear systems analysis package using the facilities developed under the first two goals. A software interface (supervisor) to support and control a variety of interactive subsystem modules is described. The supervisor operates under the constraints of a large multiprogramming variable task operating system as opposed to a time …

Synthesis And Properties Of Cadmium Manganese Ferrites, B. W. Jong

Doctoral Dissertations

"The formation sequence of (Cd,Mn,Fe) (Mn,Fe)₂O₄ from the individual oxides,x CdO + (1-x) MnCO₃ + α-Fe₂O₃,was found by X-Ray diffraction. Cd(Mn,Fe)₂O₄ was formed completely from CdO·Fe₂O₃ and CdO·Fe₂O₄ at 900°C and reacted with MnFe₂O₄ for 0 < x < 0.5 and with α-Fe₂O₃ for 0.5 < x < 1.0 to form a single phase of (Cd,Mn,Fe) (Mn,Fe)₂O₄ at 1150°C. This is the first time that the details involved in the formation sequence of CdMn-ferrite have been shown. A mixture of 0.5 CdO + 0.5 MnCO₃ + α-Fe₂O₃ was calcined at 900°C for 2 hrs forming Cd(Mn,Fe)₂O₄ with no Cd present in the other phases. Sintering was accomplished at 1150°C for 30 minutes forming a single phase of Cd₀.₅Mn₀.₅Fe₂O₄ with a bulk sintered density of 98-99% of the X-Ray density. The rate of changing density followed the relationship, p = K ln t + c, at temperatures between 1050°C and 1300°C. Magnetic properties of CdₓMn₁₋ₓFe₂O₄ were affected by composition x. A relationship, B = gx + h, was found between maximum magnetic flux density B and composition x at room temperature for 0 <̲ x <̲ 0.3. This was rationalized by a modification of Néel's theory. The maximum magnetic flux density decreased with increasing cadmium concentration for 0.3 < x <̲ 0.5. This decrease was attributed to the changing direction of the magnetic moment in the octahedral site sub-lattice according to the superexchange theory. No magnetic properties were observed due to the formation of a compensated antiferromagnetic phase for 0.5 < x <̲ 1.0. Maximum magnetic flux density increased with bulk density, while the coercive force decreased with the grain growth and the initial permeability increased with the bulk density and grain size. A stator core used for a-c electric motor application was formed by pre-sintering at 900⁰C for 2 hrs. Slots were then sawed with a tungsten carbide blade and final sintering was accomplished at 1150⁰C for 1 hr"--Abstract, pages iii-iv.

The Effect Of Impurities And Additives On The Electrowinning Of Zinc, Haruhisa Fukubayashi

Doctoral Dissertations

"The effect of various impurities, commonly found in zinc electro-winning solutions, on the surface morphology of deposited zinc was investigated. Individual additions of the impurities Al, Ag, Cd, Co, Cr, Cu, Ge, Mn, Ni, Sb, Sn, Ti, PbO₂ , PbSO₄, and HCl were studied. In a few cases additives of animal glue, gum arabic, and Na₂SiO₃, were used individually or in combination, to determine their effect on the surface structure of the deposited zinc. Comparisons were then made with deposits from a pure electrolyte consisting of H₂SO₄ and Zn⁺², 200 and 65 g/l, respectively. The zinc was deposited on a …

Secondary Techniques For Increasing Fault Coverage Of Fault Detection Test Sequences For Asynchronous Sequential Networks, Lewis Ronald Hoover

Doctoral Dissertations

"The generation of fault detection sequences for asynchronous sequential networks is considered here. Several techniques exist for the generation of fault detection sequences on combinational and clocked sequential networks. Although these techniques provide closed solutions for combinational and clocked networks, they meet with much less success when used as strategies on asynchronous networks. It is presently assumed that the general asynchronous problem defies closed solution. For this reason, a secondary procedure is presented here to facilitate increased fault coverage by a given fault detection test sequence. This procedure is successful on all types of logic networks but is, perhaps, most …

An Exact Analysis Of Two-Dimensional Radiative Transfer In An Absorbing And Emitting Gray Medium, William F. Breig

Doctoral Dissertations

"The exact formulations for the radiative flux and the emissive power are presented for a two-dimensional, finite, planar, absorbing and emitting, gray medium in radiative equilibrium. Exact expressions are obtained for the medium subjected to the following types of boundary conditions: (1) cosine varying diffuse, (2) cosine varying collimated, (3) constant temperature strip, and (4) the strip illuminated by a uniform collimated flux. The solutions for the physically unrealistic cosine varying models are used to construct the solutions for the more practical finite strip models. The two-dimensional equations are reduced to one-dimensional equations by the method of separation of variables. …

Deformation And Fracture Of Concrete Under Uniaxial Impact Loading, Esteban Eulogio Miranda

Doctoral Dissertations

"Stress wave propagation and interaction in plain concrete leading up to spall fracture was investigated experimentally with a computer numerical analysis of the bar-geometry axial-impact loading. The critical normal fracture strain energy U and mechanical energy W criteria are proposed for the spatial and time dependence explanation of spallation in concrete. The energy criteria are special cases of a more generalized cumulative damage model of the form:....

Finite-difference analyses of the wave propagation and interactions in the split Hopkinson bar showed that early failure in brittle materials limits the application of the conventional method of analysis because equilibrium in the …