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Articles 5401 - 5430 of 5718
Full-Text Articles in Entire DC Network
An Acceleration Technique For A Conjugate Direction Algorithm For Nonlinear Regression, Larry Wilmer Cornwell
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
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 …
Selected First Row Transition Metal Coordination Compounds Of 2-(N-Aminomethyl)-3-Quinuclidinone Chelates, Richard Cecil Dickinson
Selected First Row Transition Metal Coordination Compounds Of 2-(N-Aminomethyl)-3-Quinuclidinone Chelates, Richard Cecil Dickinson
Doctoral Dissertations
"As part of a project directed towards elucidating the characteristics of ligands which coordinate to give complexes having tetrahedral structures, a study of chelates containing the bulky quinuclidine group has been made. With 2-(N-morpholinylmethyl)-3-quinuclidinone (MQN), complexes having the general formula M(MQN)X₂ were prepared where the metal ion was Co(II), Ni(II), Fe(II), Cu(II), and Mn(II). The ligands 2-(N-piperidinylmethyl)-3-quinuclidinone (PQN) and 2-(N-dimethylaminomethyl)-3-quinuclidinone (DQN) were prepared along with the analogous cobalt(II) chloride complexes. The series of complexes Co(MQN)X₂ where X = Cl, Br, or I were prepared, and magnetic susceptibilities and spectral data obtained. They have room temperature magnetic moments in the range …
The Utilization Of High Sensitivity Noble Gas Mass Spectrometry In The Detection Of Iodine-129 And Plutonium-244, Mervet S. Boulos
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 (t1/2 = 17 x 106 years) was found in CO₂ -rich gas while evidence for the now extinct 244Pu (t1/2 = 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 …
Ionization Mechanisms In Cesium, Yu Bong Hahn
Ionization Mechanisms In Cesium, Yu Bong Hahn
Doctoral Dissertations
"Autoionizing states in Cs between 12 and 20 eV have been studied by electron impact. The retarding-potential-difference(RPD) method was used to obtain an electron beam with energy spread of about 0.1 eV. To determine the threshold energies, inelastically scattered electrons were analyzed by the trapped-electron method. We have been able to identify about 20 levels, and the agreement with spectroscopic data is excellent. A peak appearing at 12.80 eV is probably due to the quartet states observed by Feldman and Novick"--Abstract, page 2. "The structure in the electron impact ionization cross section in cesium can be partially accounted for by …
Geochemical Anomalies In The Igneous Wall Rock At Mayflower Mine, Park City District, Utah, Zuhair Al-Shaieb
Geochemical Anomalies In The Igneous Wall Rock At Mayflower Mine, Park City District, Utah, Zuhair Al-Shaieb
Doctoral Dissertations
"Approximately 500 samples were collected from the igneous wall rock of the Mayflower Mine, Park City District, Utah. The mine is the sixth largest gold producer in the United States. The samples were analyzed for copper lead, zinc silver, manganese, sodium, potassium, calcium, magnesium and iron by atomic absorption spectrophotometry. Gold was determined by neutron activation analysis, silicon and sulfur by x-ray fluorescence spectrometery. The calculation of the mineral norm from the chemical analysis showed the wall rock to be of granodioritic composition. A study of selected vein samples indicates that the copper, silver and gold content in the veins …
Time Resolved Measurements Of Droplet Growth In A Wilson Cloud Chamber, Michael Anthony Vietti
Time Resolved Measurements Of Droplet Growth In A Wilson Cloud Chamber, Michael Anthony Vietti
Doctoral Dissertations
"The growth rates of water drops in a Wilson expansion cloud chamber are measured with air, argon and helium as the carrier gas, in the size range of .5 to 10 microns. The drops growing in the supersaturated chamber exhibit oscillations in the scattered intensity as predicted by Mie theory. Scattered intensity is measured at 30 degrees to the He-Ne laser beam. Supersaturation ratios during growth range from S =1.2 to S = 3.5 for all three gases. The initial temperature is measured and the pressure is monitored continuously so that droplet growth theory can be compared with experiment. Three …
Structure Of Zero Divisors, And Other Algebraic Structures, In Higher Dimensional Real Cayley-Dickson Algebras, Harmon Caril Brown
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 …
The Structural Behavior Of Cold-Formed Steel Members With Perforated Elements, Charles S. Davis
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 …
Condensation And Sublimation Of Carbon Dioxide And Water Molecules At Cryogenic Temperatures, Victor Cazcarra
Condensation And Sublimation Of Carbon Dioxide And Water Molecules At Cryogenic Temperatures, Victor Cazcarra
Doctoral Dissertations
"Measurements of the condensation coefficient of CO₂ and H₂O have been made using a molecular beam and quartz crystal microbalances. The dependence of the condensation coefficient on variables such as population density on the substrate, temperature of the substrate, molecular beam intensity and temperature of the molecular beam, was investigated. The results are explained using heterogeneous nucleation theory for low density population, and a new approach for high density population is presented. The rate of sublimation of these two gases was measured directly. The results are reported in terms of vapor pressure in the range 10⁻⁹ to 10⁻⁴ Torr. The …
Wall Rock Geochemistry Of The Chester Vein, Sunshine Mine, Kellogg, Idaho, Nicholas Howard Tibbs
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 …
The Scattering Of Elastic Waves By Void Cavities, Jerry Lee Davis
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 …
Methods And Applications Of Systems Identification, Allen Glenn Behring
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 …
Hydro-Thermal Generation Unit Commitment And Dispatch Using A Dynamic Programming Approach, Warren Dean Graham
Hydro-Thermal Generation Unit Commitment And Dispatch Using A Dynamic Programming Approach, Warren Dean Graham
Doctoral Dissertations
"The problem of thermal unit commitment is solved with dynamic programming. A practical example is given which solves the problem for a six generator system over a one year time span. This long range solution is used with a hydro optimization procedure to give an optimized hydro-thermal unit commitment solution. From this, a worth of hydro value is computed for each month, which may be used in the daily dispatching of thermal units and hydro. Applications of the program are also shown for aiding in generator maintenance scheduling and evaluating purchase power contracts with neighboring utilities. Error analysis is made …
An Experimental Investigation Of The Effects Of Ambient And Heated Steady Flow And Intense Sound Levels On The Response Of Acoustic Filter Elements, Raymond H. Schaffart
An Experimental Investigation Of The Effects Of Ambient And Heated Steady Flow And Intense Sound Levels On The Response Of Acoustic Filter Elements, Raymond H. Schaffart
Doctoral Dissertations
"The primary purpose of this research was to investigate the effects of flow and finite amplitude waves on the response of acoustic elements. A further purpose was to evaluate the effects of elevated temperatures and cross-sectional dimensions on element performance. As an integral part of this work various laboratory techniques were explored for their suitability.
Empirical models for the acoustic impedance of side branch resonators were developed for the two operational modes, i.e., flow past the resonator and finite amplitude wave inputs. A description of the complex variation of the acoustic resistance of the resonator with flow past and variable …
A Monte Carlo Calculation Of Neutron Reflection From Various Curved Surfaces, Charles Jack Kalter
A Monte Carlo Calculation Of Neutron Reflection From Various Curved Surfaces, Charles Jack Kalter
Doctoral Dissertations
"Plane parallel neutron beams normally incident upon the curved surface of a solid reflector are studied with the Monte Carlo method. The geometries studied are cylindrical, parabolic, and hemispherical. It is shown that when the curved surface is cylindrical, a small "focusing effect" occurs in the reflected neutron beam. Parabolic and hemispherical surfaces do not show "focusing". A study of the factors which determine the spatial dependence of the reflected flux shows that the probability of emergence of a neutron, traveling a fixed distance from a point inside the reflector, depends upon the curvature of the surface. It is only …
A Study Of Biochemical Mechanisms Involved In The Neuromuscular Blocking Activities Of Saxitoxin And Tetrodotoxin, Elwood Wilbur Hopkins Iii.
A Study Of Biochemical Mechanisms Involved In The Neuromuscular Blocking Activities Of Saxitoxin And Tetrodotoxin, Elwood Wilbur Hopkins Iii.
Doctoral Dissertations
No abstract provided.
Investigations Of The Processes Of Discoloration And Decay Of Sugar Maple, Acer Saccharum, Associated With Fomes Connatus, Terry Alan Tattar
Investigations Of The Processes Of Discoloration And Decay Of Sugar Maple, Acer Saccharum, Associated With Fomes Connatus, Terry Alan Tattar
Doctoral Dissertations
No abstract provided.
The Calculation Of Vander Waals' Constant By The Extended Hartree-Fock Wave Function, Jwe-Son Kuo
The Calculation Of Vander Waals' Constant By The Extended Hartree-Fock Wave Function, Jwe-Son Kuo
Doctoral Dissertations
No abstract provided.
Neometric Spaces, Stephen Aurom Kenton
The Diffraction Of Plane Sound Waves By A Perfectly Reflecting Quarter-Plane, Curtis Spaulding Morse
The Diffraction Of Plane Sound Waves By A Perfectly Reflecting Quarter-Plane, Curtis Spaulding Morse
Doctoral Dissertations
No abstract provided.
Study Of The Cosmic Ray Modulation With Neutron Multiplicity Analyzers, Partap Singh
Study Of The Cosmic Ray Modulation With Neutron Multiplicity Analyzers, Partap Singh
Doctoral Dissertations
No abstract provided.
Cellular Localization Of Five Exoprotein Antigens Of Staphylococcus Aureus, Isaac Albert Wamola
Cellular Localization Of Five Exoprotein Antigens Of Staphylococcus Aureus, Isaac Albert Wamola
Doctoral Dissertations
No abstract provided.
Characteristics And Purification Of Indoleacetic Acid Oxidase In Yellow Birch, Merrill C. Hoyle
Characteristics And Purification Of Indoleacetic Acid Oxidase In Yellow Birch, Merrill C. Hoyle
Doctoral Dissertations
No abstract provided.
Some Factors Affecting The Concentration And Properties Of Carrageenan In Chondrus Crispus, Stackhouse, Stephen William Fuller
Some Factors Affecting The Concentration And Properties Of Carrageenan In Chondrus Crispus, Stackhouse, Stephen William Fuller
Doctoral Dissertations
No abstract provided.
Rocket Measurements Of Field Aligned Currents And Energy Spectra Of Charged Particles In An Auroral Display, Lawrence Wah Choy
Rocket Measurements Of Field Aligned Currents And Energy Spectra Of Charged Particles In An Auroral Display, Lawrence Wah Choy
Doctoral Dissertations
No abstract provided.
The Effect Of Temperature On The Development Of Melampsorella Caryophyllacearum And The Method Of Penetration Of Stellaria Media By Thefungus, William Howard Pawuk
The Effect Of Temperature On The Development Of Melampsorella Caryophyllacearum And The Method Of Penetration Of Stellaria Media By Thefungus, William Howard Pawuk
Doctoral Dissertations
No abstract provided.
Mhd Waves Near The Magnetopause, Allan Wolfe
Mhd Waves Near The Magnetopause, Allan Wolfe
Doctoral Dissertations
No abstract provided.
Perception And Scientific Observation: A Challenge To The Assumption Of Objectivity, Raymond E. Rainville
Perception And Scientific Observation: A Challenge To The Assumption Of Objectivity, Raymond E. Rainville
Doctoral Dissertations
No abstract provided.
The Effect Of Behavioral Context On Some Aspects Of Adult Disciplinary Practice And Affect, Judith Elaine Stevens
The Effect Of Behavioral Context On Some Aspects Of Adult Disciplinary Practice And Affect, Judith Elaine Stevens
Doctoral Dissertations
No abstract provided.