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Articles 3721 - 3750 of 4905
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A Statistical Hydrologic Simulation Model, Ronald L. Wycoff
A Statistical Hydrologic Simulation Model, Ronald L. Wycoff
Masters Theses
"Simulation of a physical system requires knowledge of all components of the system and their interactions. A probabilistic simulation model of a hydrologic system is developed from short term continuous, sychronized rainfall-runoff records. The individual components of the system area the time between and duration of storms, the depth of rain occurring in each time period of the storm, precipitation excess relations, and the watersheds unit hydrograph. The available data is used to define or develop the probabilistic models involved. The only nonprobabilistic model employed is the watersheds unit hydrograph. It is found that the time between and duration of …
Calculation Of Eddy Current Loss Of A Disc, Kou Quen Chang
Calculation Of Eddy Current Loss Of A Disc, Kou Quen Chang
Masters Theses
"A method is presented to calculate the eddy current losses of a uniform disc with an opening in the center and excited by a circular current loopage First, the disc is subdivided into smaller concentric rings, then the self-inductances, the mutual inductances between these smaller rings, the mutual inductances between the excitation coil and the smaller rings, and the resistance of the rings are calculated. Next, the eddy current flowing in each ring is obtained by solving a complex matrix equation of the form [X] [I] = [V] where X is the impedance matrix, I is the eddy current matrix, …
Digested Sludge Dewatering On Drying Beds Under Controlled Environmental Conditions, Daniel James Harris
Digested Sludge Dewatering On Drying Beds Under Controlled Environmental Conditions, Daniel James Harris
Masters Theses
"The dewatering characteristics of anaerobically digested primary and activated sludge were investigated under eight selected combinations of laboratory controlled air temperature and relative humidity using three open, drained model beds, as well as a closed, drained and an open, nondrained bed. The evaporation rate from a free water surface was also determined. Moisture content, drainage, evaporative weight loss, and sludge surface recession were measured and recorded periodically throughout the two week period of each of the eight experiments. Relationships were shown to exist between sludge moisture content, evaporation rate from a free water surface, and the parameters 6T (the difference …
Variable-Threshold-Mixed-Weight Threshold Element, Cheng-Chung Liu
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 …
A Computerized Decision Model For Making Quantitative Decisions With Regards To The Department Of Army's Equipment Improvement Recommendations, Lewis Neri
Masters Theses
"The management decision technique, currently in use, of determining priority of EIR evaluation is basically that of "feel and experience" along with the "most pressure" applied from outside the responsible organization. The feasibility of a computerized management decision concept has been studied at the lowest system with the objective of applying this to the next higher systems and finally arriving at an overall system value to obtain system priority. This study develops the technology of operations research and the associated computer techniques, delineates the problem and develops a mathematical model to simulate this management decision technique. Furthermore, it utilizes logical …
Inclusion Theorems For Boundary Value Problems For Delay Differential Equations, Leon M. Hall
Inclusion Theorems For Boundary Value Problems For Delay Differential Equations, Leon M. Hall
Masters Theses
"In this thesis existence and uniqueness of solutions to certain second and third order boundary value problems for delay differential equations is established. Sequences of upper and lower solutions similar to those used by Kovač and Savčenko are defined by means of an integral operator, and conditions are given under which these sequences converge monotonically from above and below to the unique solution of the problem. Some numerical examples for the second order case are presented. Existence and uniqueness is also proved for the case where the delay is a function of the solution as well as the independent variable"--Abstract, …
Synthesis Of Active Distributed Rc Networks Via The W=E[Superscript Square Root Of S] Transmission, Roy Dale Hensley
Synthesis Of Active Distributed Rc Networks Via The W=E[Superscript Square Root Of S] Transmission, Roy Dale Hensley
Masters Theses
"The material presented here provides a means for synthesis of networks containing uniformly distributed RC elements. After transforming the desired transfer function into a function rational in W = e[superscript square root of sRC] , state-variable synthesis methods are applied to obtain a model containing elements with transfer functions of the form 1/W. A circuit is then presented for the 1/W block along with error analysis and design procedures for use in construction of the model. The elements of the synthesis procedures of Wyndrum and O'Shea are presented for comparison. Furthermore, synthesis of functions rational in W and Θ = …
A Measurement Of The Capture Coefficient And Of The Vapor Pressure Of Co₂ From 69ºk To 80ºk, Michel Louis Chouarain
A Measurement Of The Capture Coefficient And Of The Vapor Pressure Of Co₂ From 69ºk To 80ºk, Michel Louis Chouarain
Masters Theses
"The capture coefficient of CO₂ gas at 135ºK on a surface of CO₂ at temperatures between 69ºK and 80ºK is measured by means of quartz crystal microbalances. The vapor pressure of CO₂ is measured in the same range of temperature"--Abstract, page ii.
Freshwater Losses To The Sea And Water Level Decline In Northwest Libya, Mohammed Ahmed Attiga
Freshwater Losses To The Sea And Water Level Decline In Northwest Libya, Mohammed Ahmed Attiga
Masters Theses
"The area studied in this investigation, located in Tripolitania, Libya, between 13º and 16º east longitude and 31º and 33º north latitude, covers about 42,000 square kilometers. It is divided topographically into two parts. They are the coastal zone to the north and the Jebel (plateau) zone to the south. Some wadis which rise in the Jebel drain northward across the area to the sea. The temperature in the area ranges from 5ºC to 19ºC in the winter and from 19ºC to 40ºC in the summer. Precipitation in the area ranges from 380 millimeters to less than 100 millimeters. The …
A Triangular Element For Numerical Solutions Of Axisymmetric Conduction Problems In Cylindrical Coordinates, Prafulla Chandra Mahata
A Triangular Element For Numerical Solutions Of Axisymmetric Conduction Problems In Cylindrical Coordinates, Prafulla Chandra Mahata
Masters Theses
"The triangular element is one of the many suitable elements which are used in finite difference methods as applied to conduction heat transfer. Such elements find many applications in conduction problems in Cartesian coordinates. This work proposes a new triangular element for axisymmetric conduction problems in cylindrical coordinates. The validity and workability of the networks formed by the proposed triangular elements are strengthened by selected examples. The work is completed by the application of the triangular element to an industrial problem having irregular boundaries. The results are compared with the solution obtained by the finite element method"--Abstract, page ii.
The Design Of A Lightning Data Interface, Larry Lee Hosto
The Design Of A Lightning Data Interface, Larry Lee Hosto
Masters Theses
"A system for the processing of lightning stroke location data has been designed. The system will be used for studying the correlation of lightning and thunderstorm precipitation. The lightning stroke location system has been developed to gain further information about the cause-effect relationship between lightning stroke activity and thunderstorm precipitation. The system will consist of an analog computational network to find the tangent of the azimuth of the lightning stroke, an analog-to-digital converter, and a computer program which will process and store data on magnetic tape. This paper will discuss the design of the analog computational network and the computer …
The Oxidative Decarboxylation Of Aminopolycarboxylic Acids With Cerium (Iv) In Sulfuric Acid, Rita Kathleen Hessley
The Oxidative Decarboxylation Of Aminopolycarboxylic Acids With Cerium (Iv) In Sulfuric Acid, Rita Kathleen Hessley
Masters Theses
"The rates of oxidation of four chelating agents, NTA, EDTA CDTA, and DTPA with Ce(IV), in sulfuric acid media, were determined spectrophotometrically by a stopped-flow technique. The reductive ability is in the order CDTA>EDTA>DTPA>NTA. The influence of varying the acidity of the medium was studied, and in each case a maximum in the rate constant [H +] plot was observed. A possible interpretation of the reactivities and the influence of acidity is advanced"--Summary, page 1.
Normal Mode Method Applied To The Transient Longitudinal Vibrations Of A Finite Rod With Material Damping And Viscoelastic Dispersion, David Arthur Levene
Normal Mode Method Applied To The Transient Longitudinal Vibrations Of A Finite Rod With Material Damping And Viscoelastic Dispersion, David Arthur Levene
Masters Theses
"Longitudinal vibrations of a finite rod with material damping and frequency dependent material properties are examined. The normal mode method is used to investigate the transient response of a rod which is free to move in the longitudinal direction and is subjected to a transient longitudinal loading condition at one end. The equations of motion are derived and solved using both the differential equations approach and the energy methods approach of the normal mode method. The effects of material damping and frequency dependent material properties are considered by formulating the stress-strain relation for the material such that the modulus of …
Shop Level Maintenance Of Inertial Platforms Without A Surveyed Site, Max E. Bott
Shop Level Maintenance Of Inertial Platforms Without A Surveyed Site, Max E. Bott
Masters Theses
"The initial installation of a rotary tilt table for an aircraft inertial navigation system test facility includes accurately aligning the rotary tilt table to local level and true north coordinates. The survey techniques presently employed are an encumbrance during installation and complicate remote deployment. The objective of this thesis is to determine if an inertial platform or platforms can practically be used to replace the role of the survey techniques in the rotary tilt table alignment. The construction, capability and operation of a rotary tilt table are reviewed. The tests necessary to test and calibrate an inertial platform are outlined, …
Triangular Signal Stabilization Of Nonlinear Systems, Kamaleddin Yadavar Nikravesh
Triangular Signal Stabilization Of Nonlinear Systems, Kamaleddin Yadavar Nikravesh
Masters Theses
"Many nonlinear systems display self-sustained oscillations which are often undesirable. The stabilizing effect of a high frequency input signal on an oscillating system with one nonlinearity is determined by the characteristics of the nonlinear element in the system, the linear portion of the system and the amplitude of the signal. This investigation has been concerned with the effect of a triangular wave stabilizing signal on these self oscillations. The equivalent gains for several common nonlinearities are derived. The pseudo describing function introduced by Oldenburger and Boyer for sinusoidal stabilization has been extended to the triangular wave case, and it is …
Intrinsic Viscosities Of Linear Polyethylene, Joseph Shing Chiang
Intrinsic Viscosities Of Linear Polyethylene, Joseph Shing Chiang
Masters Theses
"Intrinsic viscosity measurements were performed on linear polyethylene (Marlex 6009) in decalin at 135ºC and in diphenyl ether at 163.9ºC. Molecular weights ranging from 3x10³ to 35x10⁴ were studied. It was found that for linear polyethylene of molecular weight up to 35x10⁴, the tedious intrinsic viscosity measurement could be replaced by inherent viscosity measurement at a concentration of 0.1 grams per deciliter. The effect of shear on viscosities measured in decalin increased as the molecular weight of the sample increased. The shear rate effects on intrinsic viscosities were negligible. On the other hand, the shear rate effect on the Huggins' …
Shear Properties Of An Organic Soil And The Same Soil With The Organic Matter Removed, David Eugene Daniels
Shear Properties Of An Organic Soil And The Same Soil With The Organic Matter Removed, David Eugene Daniels
Masters Theses
"The effect of strain rate on the shearing properties of an organic A̲ horizon Bryce clay and the same soil treated with hydrogen peroxide to remove the organic matter was studied. For both soils, the pore pressures were found to be independent of strain rate, and dependent only on the increment of strain during shear. The effect of the hydrogen peroxide treatment on the shear properties of an inorganic Bryce B̲ horizon clay was also studied. It was concluded that the hydrogen peroxide does not affect the mineral properties of the Bryce clay and serves only to selectively remove organic …
Integrability Of The Sums Of The Trigonometric Series 1/2 Aₒ + ∞ [Over] Σ [Over] N=1 AN Cos Nθ And ∞ [Over] Σ [Over] N=1 AN Sin Nθ, John William Garrett
Integrability Of The Sums Of The Trigonometric Series 1/2 Aₒ + ∞ [Over] Σ [Over] N=1 AN Cos Nθ And ∞ [Over] Σ [Over] N=1 AN Sin Nθ, John William Garrett
Masters Theses
"The trigonometric series C = 1/2 aₒ + ∞ [over] Σ [over] [n=1] a[subscript n] cos nΘ and S = ∞ [over] Σ [over] n=1 a[subscript n] sin nΘ, where {a[subscript n]} monotonically decreases to zero both converge almost everywhere to functions f and g respectively. f (or g) is L iff C (or S) is the Fourier series of f (or g) iff term-by-term integration of C (or S) is valid. There are three equivalent conditions, each of which implies that C is the Fourier series of f...."--Abstract, page ii.
A Hybrid Computer Solution Of The Swing Equation, Donald Wayne Shaw
A Hybrid Computer Solution Of The Swing Equation, Donald Wayne Shaw
Masters Theses
"Models for the governor and exciter control systems are presented and the development of a hybrid computing system including these models is described. A technique for including the governor and exciter effects into the solution of the power system swing equation is also discussed. A hybrid computing system consisting of an SCC 650 digital computer, hybrid interface, and an EAI-TR-48 analog computer is used to study five test cases. The test cases involve basically the same example system with different values for fault clearing times and machine inertias. The results of each test case are briefly discussed with relevance to …
Compressibility Effects On Transient Gas Pipe Flow, Gerald Francis Mouser
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 …
An Investigation Of A Bistable Oscillator Used In A Phase Modulated Control Circuit, Yu-Fang Yen
An Investigation Of A Bistable Oscillator Used In A Phase Modulated Control Circuit, Yu-Fang Yen
Masters Theses
"A primary component in the investigation of phase modulated control systems is bistable oscillator which converts a constant oscillation signal to control the system. The oscillator is feedback type that utilizes a feedback capacitance and resistance in each feedback path to change its frequency. The theoretical behavior of bistable oscillator was investigated and the non-dimensional results were set for convenience in determining the oscillation period. The control circuit which based on the oscillator was also presented a form of suitable circuit for direct application to practical control problems"--Abstract, page ii.
Development Of An Elastic-Plastic Finite Element Program With The Initial Strain Approach, Vernon Dale Allen
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.
Hydrothermal Alteration Of Ash-Flow Tuffs In The Indian Peak District Of Southwestern Utah, Michael Allan Tolley
Hydrothermal Alteration Of Ash-Flow Tuffs In The Indian Peak District Of Southwestern Utah, Michael Allan Tolley
Masters Theses
"Careful petrographic study of the ash-flow tuffs in the Indian Peak District of southwestern Utah reveals hydrothermal alteration around the fluorite veins. The alteration minerals themselves and the intensity of alteration vary with distance from the veins. Primary plagioclase has altered to secondary feldspar, calcite, sericite, and traces of epidote and zoisite. Hornblende and biotite have altered to chlorite, calcite, and secondary iron oxide, and traces of epidote and zoisite. Diopside has changed to calcite and secondary iron oxide. An overall picture of the mining district shows that certain minerals increase and others decrease as one nears the veins. Hydrothermal …
Fossil Otoliths Of Some Lower Cenozoic Perciform Fishes Of The Gulf Coast, Mostafa Juma Salem
Fossil Otoliths Of Some Lower Cenozoic Perciform Fishes Of The Gulf Coast, Mostafa Juma Salem
Masters Theses
"Nineteen perciform species from the lower Cenozoic and one Recent species are described, and included under eight genera. The main characters that were considered as generic are the outline of the sagitta and the structure of the sulcus. The other features of the otolith were regarded as secondary in importance. The characters that were believed to be valuable at specific level are almost the same as those for the genus but in more detail. These species are considered to be within the Suborder Percoidei. The fossil species of "Nemipterus" were put in the Family Nemipteridae as they resembled the Recent …
High Temperature Compressive Creep In Mullite, Peter C. Smith
High Temperature Compressive Creep In Mullite, Peter C. Smith
Masters Theses
"Compressive creep measurements were made on two groups of mullites at temperatures between 1455ºC and 1520ºC. The first group consisted of commercially manufactured mullites. The second group was made up of 7 different mullite compositions spanning the alumina-silica solid solution range from 3Al₂O₃ • 2SiO₂ to 2Al₂O₃ • SiO₂ . Thermal activation energies and stress exponents were calculated for the mullites in the second group. Steady state strain rates taken at 1460ºC under loads of 100 and 110 psi varied between 1.3x10⁻⁴ in/in/hr and 15.4x10⁻⁴ in/in/hr. Activation energies were between 109 Kcal/mole and 204 Kcal/mole. Stress exponents calculated from data …
Distribution, Petrology, And Environment Of The St. Louis-Ste. Genevieve Transition Zone In Missouri, Donald Howerton Fielding
Distribution, Petrology, And Environment Of The St. Louis-Ste. Genevieve Transition Zone In Missouri, Donald Howerton Fielding
Masters Theses
"In eastern Missouri, southeastern Iowa, and western Illinois - a transition zone, a body of rock consisting of several lithosomes which has a geographic extent measured in scores to hundreds of miles and which lies between a single overlying formation and a single underlying formation and which has lithologic and/or paleontologic properties common to both the overlying and the underlying formations, was found to exist between the St. Louis and the Ste. Genevieve formations. This transition zone is called the St. Louis-Ste. Genevieve Transition Zone, and is shown to possibly be due to continuous deposition between these two times and …
Stability And Synthesis Of Transfer Functions Rational In W = E To The Power Of The Square Root Of T (S² + Bs + C) And Omega = The Square Root Of T (S² + Bs + C), James Fred Archer
Stability And Synthesis Of Transfer Functions Rational In W = E To The Power Of The Square Root Of T (S² + Bs + C) And Omega = The Square Root Of T (S² + Bs + C), James Fred Archer
Masters Theses
"The bounded input-bounded output stability is investigated for networks containing uniformly distributed LRGC, LRC, GRC and G(ω)RC elements. The region of stability in the W plane (W = e to the power of the square root of (s² + bs + c), Θ plane (Θ = the square root of (s² + bs + c), and S plane (S = s²+bs+c) is found in each case so that if the poles of a transfer function rational in W, Θ or S lie within this region the system is stable. After obtaining a desired transfer function rational in W = e …
Anodic Oxidation Of Ethylenediaminetetraacetic Acid On Pt In Acid Sulfate Solutions, Howard Ho-Wei Jiang
Anodic Oxidation Of Ethylenediaminetetraacetic Acid On Pt In Acid Sulfate Solutions, Howard Ho-Wei Jiang
Masters Theses
"The anodic oxidation of EDTA was studied in acid sulfate solutions on platinized-Pt at 25ºC. Polarization relationships were obtained for the EDTA concentration range 3. 42 x 10⁻⁵ to 3. 42 x 10⁻³ M and pH range 0. 35 to 3. 80. Numerous reaction products were identified that indicated a sequential removal of acetate groups from the EDTA, each by an initial decarboxylation followed by a reverse Schiff-type reaction, that produced formaldehyde and the corresponding amine. A reaction sequence which correlated the experimental data involved Frumkin-type adsorption of the EDTA species through an unionized acetate group followed by a rate-determining …
A Study Of Radiative Heat Transfer From A Spherical Layer, Hakimuddin Kalimuddin Khalil
A Study Of Radiative Heat Transfer From A Spherical Layer, Hakimuddin Kalimuddin Khalil
Masters Theses
"The problem of radiative heat transfer from a spherical layer of absorbing-emitting gas has been studied. First, the medium is assumed to be gray and then nongray. A thorough survey of literature from fields other than heat transfer, such as astrophysics and neutron transport has been made to stimulate further interest in this important area. To gain some insight into the effect of various parameters on the heat transfer, simple physical situations involving isothermal medium are considered. Comparison of the results obtained for the flux from the spherical and planar layers reveal that the curvature becomes increasingly important as the …
Sediment Properties And Depositional Environment Of The Minnelusa Formation (Permo-Pennsylvanian), Northern Black Hills, South Dakota And Wyoming, El-Magtuf Taleb Taleb
Sediment Properties And Depositional Environment Of The Minnelusa Formation (Permo-Pennsylvanian), Northern Black Hills, South Dakota And Wyoming, El-Magtuf Taleb Taleb
Masters Theses
"Permo-Pennsylvanian sedimentary rocks of the Minnelusa Formation of the Black Hills uplift, South Dakota and Wyoming, can be divided into upper, middle and lower divisions on the basis of lithology. The upper portion of 150 to 200 feet consists of gray and yellow sandstone, with some carbonates and shales in some sections. The middle portion, about 200 to 220 feet thick consists of gray and red sandstone with carbonate members including the prominent dolomite member at the base; some of the carbonates are cherty. The lower portion, 20 to 60 feet thick, consists of pink sandstone, arenaceous dolomite and thin …