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Structure Of Zero Divisors, And Other Algebraic Structures, In Higher Dimensional Real Cayley-Dickson Algebras, Harmon Caril Brown

Doctoral Dissertations

"Real Cayley-Dickson algebras are a class of 2ⁿ-dimensional real algebras containing the real numbers, complex numbers, quaternions, and the octonions (Cayley numbers) as special cases. Each real Cayley-Dickson algebra of dimension greater than eight (a higher dimensional real Cayley-Dickson algebra) is a real normed algebra containing a multiplicative identity and an inverse for each nonzero element. In addition, each element a in the algebra has defined for it a conjugate element ā analogous to the conjugate in the complex numbers. These algebras are not alternative, but are flexible and satisfy the noncommutative Jordan identity. Each element in these algebras can …

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 …

The Structural Behavior Of Cold-Formed Steel Members With Perforated Elements, Charles S. Davis

Doctoral Dissertations

"Analytical and experimental investigations have been conducted to study the influence of perforations on the structural behavior of cold-formed steel structural members. Since in many cases, the load-carrying capacity of cold-formed steel members depends on the buckling behavior of individual component elements, emphasis has been concentrated on the study of the instability and post-buckling strength of perforated elements. In this investigation, the buckling loads and post-buckling strength of stiffened and unstiffened compression elements having single circular and square holes have been studied analytically by using the finite element method. The effects of different holes on the buckling coefficient have been …

A Study Of The Solid Regions In The System Zr-Te, Frances Dolores Jenkins

Doctoral Dissertations

"Relative intensity measurements of X-ray powder diffraction lines were made of compositions in the region ZrTe₀.₅ to ZrTe₂.₀, fired between 600º and 817ºC in evacuated sealed tubes. The experimental relative intensities of samples between ZrTe and ZrTe₂ were compared with values calculated for several theoretical models with different Zr vacancy ordering schemes and Te vacancy concentrations. The most probable structural model for compositions in the range ZrTe to ZrTe₁.₅ is one in which the number of Zr vacancies located at z = 0 ranges from 0% to 30%, with the concentration of Te vacancies ranging from 0 to 35%. A …

The Utilization Of High Sensitivity Noble Gas Mass Spectrometry In The Detection Of Iodine-129 And Plutonium-244, Mervet S. Boulos

Doctoral Dissertations

"Mass spectrometric analysis of the xenon isotopes in natural gas wells demonstrates that radioactive isotopes of element number 53 (I) and element number 94 (Pu) were present at the time of the Earth's formation. Evidence for the now extinct nuclide¹²⁹I (t_1/2 = 17 x 10⁶ years) was found in CO₂ -rich gas while evidence for the now extinct ²⁴⁴Pu (t_1/2 = 82 x 10⁶ years) was discovered in other natural gas wells. The amounts of ¹²⁹I in thyroids was measured by combining neutron activation analysis with noble gas mass spectrometry. The current …

An Asynchronous Circuit Design Language System, Gregory Martin Bednar

Doctoral Dissertations

"This paper presents a system for specifying the behavior of asynchronous sequential circuits. The system consists of a special purpose Asynchronous Circuit Design Language (ACDL), a translator and a flow table generation algorithm. The language includes many special features which permit quick and precise specification of terminal behavior. It is best suited for problems originating from a word description of the circuit's operation. The translator is written with the XPL Translator Writing System and is a syntax-directed compilation method. From the translated ACDL specifications, the flow table algorithm generates a primitive flow table which is the required input for the …

Wall Rock Geochemistry Of The Chester Vein, Sunshine Mine, Kellogg, Idaho, Nicholas Howard Tibbs

Doctoral Dissertations

"The Chester vein has been the major source of ore from the Sunshine mine, largest single producer of silver in the world. 425 samples of quartzite and argillite wall rocks were collected in 13 traverses across this vein on the 4400, 4600, and 4800 mining levels. These samples were analyzed for aluminum, magnesium, calcium, sodium, potassium, manganese, iron, lead, copper, and zinc by atomic absorption spectroscopy, and for silicon and sulfur by x-ray emission spectroscopy. Element distribution plots, linear correlation coefficient matrices, varimax factor analysis, and cluster analysis were employed to determine the geochemical processes that occurred in the wall …

Methods And Applications Of Systems Identification, Allen Glenn Behring

Doctoral Dissertations

"A "Schmidt filter" is proposed to compute an optimal orthonormal basis for a set of "noisy" filter input functions. Procedures for determining the transfer function and inverse transfer function of the filter are given. The Schmidt filter is applied to the problem of determining mathematical models of discrete, stationary, linear, dynamic systems for the case where measurements may be corrupted by noise of unknown statistics. The identification problem is reconsidered for the case where noise and signal moments are specified. Procedures are given which insure unbiased, adaptive estimates of system order and parameters for this case. These theoretical propositions are …

The Scattering Of Elastic Waves By Void Cavities, Jerry Lee Davis

Doctoral Dissertations

"Elastodynamic multipole theory, the theory of least squares, and the theory of integral representation of solutions are employed in solving certain problems involving an elastic solid containing a source and a scatterer. Both the source and scatterer are of finite geometrical extent; they occupy non-intersecting regions. The source is separable, i.e., its mathematical specification consists of an arbitrary vector function of position multiplied by a time function, which is further assumed to be a sinusoid. The scatterer emphasized is a finite void cavity of arbitrary shape; however, scatterers composed of rigid material may also be treated. The calculation of a …

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 …

The Morphology Of Cellular Precipitation In Aluminum Rich Aluminum-Silver Alloys, Santiago Ibarra Jr.

Doctoral Dissertations

"The morphology of cellular precipitation in Al-29.8wt%Ag alloy has been investigated in bulk specimens by transmission electron microscopy and in solution treated specimens by means of hot stage microscopy. Both cellular and general precipitation were observed to occur simultaneously in quench-aged and isothermally aged alloys. By studying the early stages of precipitation in the hot stage, the mechanism for the growth of cells in Al-Ag alloys was developed. According to this mechanism, the grain boundary allotriomorphs begin to form, the boundary then interacts with the allotriomorphs by bowing, and then either trailing precipitation forms on the allotriomorphs or new lamellae …

Grain Boundary Diffusion In Ionic Crystals, Kulwant Singh Sabharwal

Doctoral Dissertations

"The diffusion of ¹³¹I in single crystals and along the tilt grain boundaries of pure and calcium chloride doped (142±5 ppm) bicrystals of sodium chloride, grown by Czochralski technique, was investigated using a microtome sectioning technique. Results on bulk diffusion in pure NaCl agree well with the results of earlier investigators and are represented by the D=(504 cm²/sec)exp (-2.27 ev/kT). Enhanced diffusion of ¹³¹I is observed along the grain boundaries and the presence of the dopant lowers the grain boundary diffusivity over the entire temperature range of 430ºC - 570ºC studied in the present investigation. Thermal activation and electrical polarization …

Radiative And Predissociative Lifetimes Of The A²Σ⁺ State Of Oh, Robert Allen Sutherland

Doctoral Dissertations

"Lifetime measurements have been made on the A²Σ⁺ state of OH by the delayed coincidence technique in conjunction with an interrupted rf discharge through water vapor. Lifetimes are reported for rotational states up to K = 29 and K = 20 in the v = 0 and v = 1 vibrational levels respectively and on the unresolved levels of v =2. A predissociation, previously predicted from relative intensity measurements, resulting from a curve crossing by the repulsive 4 Σˉ state, was observed for the rotational states above K = 23 of v = 0, for those above K = 14 …

Substituent Effects On The Magnetic Resonance Spectra Of 1, 4-Disubstituted Benzenes, Holger Er-Chah Chen

Doctoral Dissertations

"The Nuclear Magnetic Resonance spectra of five complete series of para-substituted benzenes have been investigated: the benzoic acids, benzonitriles, benzoyl chlorides, methyl benzoates and nitrobenzenes. Precise values of aromatic proton chemical shifts and coupling constants were obtained from LAOCOON3 computer analyses of the spectra. Using the relative internal chemical shift technique of Beachell and Beistel, excellent linear correlations among all five series were found. All substituents gave proton shifts which lay on the least-squares line, so it is concluded that all substituents are well behaved. Using the correlation plots the chemical shifts of the aromatic ring protons can be predicted …

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 …

Diffusiophoretic Forces Between Juxtaposed Atmospheric Particles, Allen L. Williams

Doctoral Dissertations

"The role of diffusiophoretics and Stefan flow in droplet growth by accretion and in-cloud scavenging is examined. A calculation is made for the diffusive forces between two juxtaposed spheres one or both of which are undergoing diffusional growth and the influence of the diffusive force on the trajectories of two spheres, assumed to obey the creeping flow equations is found. The results are: a) the diffusiophoretic force between two water droplets is zero. b) the diffusiophoretic force between a spherical ice particle and a water droplet, although non-zero, is too small to appreciably influence the fall trajectories. c) the diffusiophoretic …

An Acceleration Technique For A Conjugate Direction Algorithm For Nonlinear Regression, Larry Wilmer Cornwell

Doctoral Dissertations

"A linear acceleration technique, LAT, is developed which is applied to three conjugate direction algorithms: (1) Fletcher-Reeves algorithm, (2) Davidon-Fletcher-Powell algorithm and (3) Grey's Orthonormal Optimization Procedure (GOOP). Eight problems are solved by the three algorithms mentioned above and the Levenberg-Marquardt algorithm. The addition of the LAT algorithm improves the rate of convergence for the GOOP algorithm in all problems attempted and for some problems using the Fletcher-Reeves algorithm and the Davidon-Fletcher-Powell algorithm. Using the number of operations to perform function and derivative evaluations, the algorithms mentioned above are compared. Although the GOOP algorithm is relatively unknown outside of the …

The Average Dissipation Curve Of An Attenuative Layered Earth Medium, Joong Hee Chun

Doctoral Dissertations

"A feasible method of estimating the attenuative properties of a layered earth medium from a reflection seismogram has been developed. An average attenuation factor of n layers in the least squares sense is designated as ß and its usefulness in real applications is investigated. Techniques of extracting dissipation factors from both noise free and noisy reflection seismic traces are discussed. In order to describe the change of the factors with an increase of depth, an average dissipation curve the form of which is similar to the average velocity of layered medium is also introduced. Both the ß and the average …