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Articles 5971 - 6000 of 7904
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A Digital Simulation For Optimum Nonlinear Detection Of Binary Signals In Impulsive Noise, Ralph Bernard Fluchel
A Digital Simulation For Optimum Nonlinear Detection Of Binary Signals In Impulsive Noise, Ralph Bernard Fluchel
Masters Theses
"The problem of reducing the effects of impulsive noise on binary communication systems is considered. A digital simulation of such a system is developed in order to find a nearly optimum (minimum probability of error criterion) nonlinear device to precede detection. The level of the Gaussian noise power is found to be the most important parameter for determining the nearly optimum nonlinear device"--Abstract, page ii.
Efficiency And Loss Mechanism Of The Electro-Fluid Dynamic Momentum Transfer Process Applied To Propulsion Systems Using Atmospheric Air As The Working Fluid, Roger Coy Crites
Efficiency And Loss Mechanism Of The Electro-Fluid Dynamic Momentum Transfer Process Applied To Propulsion Systems Using Atmospheric Air As The Working Fluid, Roger Coy Crites
Masters Theses
"The general equations governing EFD (electrofluid dynamic) flow are established, simplified, and solved in closed form to provide a mathematical model of an ideal EFD propulsion system. This mathematical model, in conjunction with an analysis of ion-neutral and neutral-neutral molecular collision phenomena, indicates that the cause of inefficiency in the EFD propulsion system is the system entropy increase associated with the diffusion of ion momentum through the neutral fluid. This loss mechanism is shown to be analogous to resistive heating losses in a constant voltage linear electrical network and can be minimized by obtaining minimum ion mobility. It is shown …
Surface Energy Determinations In Plexiglas, Li-King Chen
Surface Energy Determinations In Plexiglas, Li-King Chen
Masters Theses
"Under irreversible conditions an effective surface energy of plexiglas for notched bars deformed in three-point bending was measured. The various equations proposed for evaluating surface energy are described and values of surface energy obtained using these equations are reported for a variety of sample dimensions. A comparison has been made between the results obtained. The effect of different notch shapes, sharp V, square U and round, on calculated values and fracture characteristics are noted. The Griffith theory is shown to be valid for large crack dimensions"--Abstract, page ii.
St. Louis Limestone, Stratigraphy And Petrography, Near Its Type Locality, Abd El-Aziz El-Hady A. Borahay
St. Louis Limestone, Stratigraphy And Petrography, Near Its Type Locality, Abd El-Aziz El-Hady A. Borahay
Masters Theses
"The St. Louis Limestone of the Upper Meramecian Series, Mississippian System, is typically lithographic, light-to light-olive gray in color, dense, and fractures conchoidally. It is brecciated, especially in the lower part, and contains some chert nodules. Oolites are present close to the top of the formation. The Salem-St. Louis contact is placed at the base of the lowest breccia zone and the top of Salem is characterized by crystalline quartz and abundance of chert nodules. The appearance of typical Ste. Genevieve oolites with sand-size quartz grains indicates the St. Louis-Ste. Genevieve contact. The St. Louis Limestone is characterized by dominance …
Next-State Equation Generation For Asynchronous Sequential Circuits - Normal Mode, Gregory Martin Bednar
Next-State Equation Generation For Asynchronous Sequential Circuits - Normal Mode, Gregory Martin Bednar
Masters Theses
"This paper describes the known methods of generating next-state equations for asynchronous sequential circuits operating in normal fundamental mode. First, the methods that have been previously developed by other authors are explained and correlated in a simple and uniform language in order that the subtle differences of these approaches can be seen. This review is then followed by a development of a new method for generating minimal next-state equations which has some advantages over the previous methods. From the comparison of the previous known methods, it is noted that any one of these methods may be desirable for certain designs …
The Design, Construction And Experimental Verification Of A Split Hopkinson Bar, Woosoon Bai
The Design, Construction And Experimental Verification Of A Split Hopkinson Bar, Woosoon Bai
Masters Theses
"This thesis presents the design considerations for a dynamic loading device utilizing a projectile fired from a tube. Also included is a preliminary investigation of the stress-strain relation, under dynamic loading with the device, for a plaster known as Hydrostone. Design of the unit is based on the split Hopkinson pressure bar originally developed by Kolsky and on a similar unit in use at the Lawrence Radiation Laboratory, Livermore, California. The strain pulses along the pressure bars are sensed by resistance wire strain gages and displayed on an oscilloscope. The oscilloscope traces are photographed and manually digitized for insertion into …
The Dinary Numerical System And Its Applications To Modern Parallel Processing Computers, Hai Chi Koo
The Dinary Numerical System And Its Applications To Modern Parallel Processing Computers, Hai Chi Koo
Masters Theses
"The Dinary Numerical System (DNS) is an extension of Binary Numerical System. By utilizing the newly developed Large-Scale-Integration technology, DNS can be implemented as a new concept of computer organization which has the merits of parallel processing. DNS consists of three field elements: they are -1, 0, and +1. Since DNS representation is not necessarily unique, new algorithms to generate the number of representations and all equivalent representations are presented in this paper. A Block-Oriented-Computer (BOC) is developed as an array of computing systems. For each of the systems, the arithmetic unit is essentially a modified Digital Differential Analyzer. The …
The Anodic Dissolution Of Tungsten, Ching-Lun Wu
The Anodic Dissolution Of Tungsten, Ching-Lun Wu
Masters Theses
"The anodic dissolution of tungsten was studied in H₂SO₄-K₂SO₄ solutions (pH= -2 to 2.5) andK₂SO₄-K₂CO₃-KOH solutions (pH = 11.5 to 14.5) at 25ºC. Faradaic efficiency studies in basic solutions showed that the metal was oxidized to the +6 state. In acid solutions, a thick protective film of yellow WO₃ was formed. Polarization measurements showed linear Tafel behavior (slope ~ 2.3RT/F) in the potential region slightly more positive than the rest potentials. An anodic dissolution mechanism is proposed which involves a surface film of W₂O₅ that is further oxidized to WO₃ and dissolves by hydrolyzation"--Abstract, page 1.
Removal Of Phosphate By Sorption On Activated Alumina, Checkman Michael Yue
Removal Of Phosphate By Sorption On Activated Alumina, Checkman Michael Yue
Masters Theses
"The purpose of this investigation was to study the removal of phosphorus from waste water by sorption on activated alumina, and determine the capacity of the alumina to sorb phosphates in the presence of other ions, the effect of the influent flow rate and phosphorus concentration on the efficiency of the process, and the feasibility of regeneration of the used alumina. The studies were conducted using deionized and tap water to which inorganic phosphate had been added, and secondary effluent from bench-scale activated sludge units. They involved batch tests employing three types of activated alumina, ALCOA XM (minus 325 mesh), …
Digital Simulation Of A Signal Conditioner/Bit Synchronizer, Quentin Reed Webb
Digital Simulation Of A Signal Conditioner/Bit Synchronizer, Quentin Reed Webb
Masters Theses
"A bit rate filter type signal conditioner/bit synchronizer used in a split-phase PCM system is modeled digitally in three stages to determine overall system performance. General computer algorithms are developed to approximate independent operation of each major segment within the device. Bit rate effects and signal time-base error are investigated yielding the characteristic G-curves for the phase detector. These characteristics facilitate subsequent analysis of a linear equivalent digital-data-transition tracking phase-locked loop under several typical time-base error input conditions. Using bit error probabilities as performance criteria, the conditioner/synchronizer is found to perform adequately at signal-to-noise ratios exceeding +10dB. For inputs below …
Probe Detection Of Microwave Perturbation In A Magnetoplasma, Show-Ran Peter Wang
Probe Detection Of Microwave Perturbation In A Magnetoplasma, Show-Ran Peter Wang
Masters Theses
"When a microwave signal with a frequency near the electron upper hybrid resonance is applied to a magnetoplasma, it will excite the plasma. The perturbation of plasma can be detected by using Langmuir probes. The particular plasma used in this experiment is an argon discharge type and the density is relatively low (n~10⁸ cm⁻³). The electron temperature is about 7000º K. Because a magnetic field is applied to the plasma, it is necessary to use the probe theory in a magnetic field to calculate the electron number density from the electron temperature. In order to determine the electron upper hybrid …
Computer Time-Sharing (T-S) "An Engineering Tool" For The Engineering Applications Of The Small Company, James Binford Summers
Computer Time-Sharing (T-S) "An Engineering Tool" For The Engineering Applications Of The Small Company, James Binford Summers
Masters Theses
"The objectives of this investigation were to illustrate the capabilities of the time-sharing (T-S) industry, identify the means by which the small sized company, with a need to solve engineering problems, can best be served through T-S, and to present T-S to these potential users. Investigation was made of distinctive T-S services to formulate a composite of the T-S industry. Examples of three distinctive T-S services were used within this composite to exemplify the variations of services within the industry. The methods a small company could use to utilize computer services were identified emphasizing T-S as the method best suited …
Mutually Dependent Heat And Mass Transfer In Laminar Tube Flow, Gary Alfred Scheffel
Mutually Dependent Heat And Mass Transfer In Laminar Tube Flow, Gary Alfred Scheffel
Masters Theses
"An investigation is performed of the mutually dependent heat and mass transfer in laminar and hydrodynamically fully developed gas flow in a tube. Sublimation of mass occurs at the tube wall so that heat and mass transfer take place between the wall and the flowing gas stream. The wall of the tube is thermally insulated from the external environment with the result that the heat of sublimation is supplied by convective transport from the gas. The solution of this problem requires the simultaneous consideration of the energy and diffusion equations, with coupling provided by the boundary conditions. Mathematical expressions are …
Heat Transfer Through A Spherical Gas Shell, Adel Nassif Saad
Heat Transfer Through A Spherical Gas Shell, Adel Nassif Saad
Masters Theses
"The radiative transfer through an absorbing-emitting gas shell contained within black concentric spheres at uniform but different temperatures was investigated. A close form exact solution and an approximate solution were derived for the case of isothermal gas layer. The two solutions appear to compare well specially at low diameter ratios, and both agree with the radiative equilibrium solution in the thin limit. An approximate method was developed for the radiative equilibrium, non-isothermal gas layer, of the above problem. The method is based on the assumption of a hyperbolic emissive power distribution through the gas shell. The jump boundary conditions were …
A Comparative Study Of Experimental And Computed Compressibility Factors Of Ethane-Carbon Dioxide-Nitrogen System, Brij Raj Misra
A Comparative Study Of Experimental And Computed Compressibility Factors Of Ethane-Carbon Dioxide-Nitrogen System, Brij Raj Misra
Masters Theses
"The purpose of this study was to provide compressibility factor data on the ethane - carbon dioxide - nitrogen system. Compressibility factors were experimentally determined for 5 mixtures at room temperature, 100ºF, 125ºF , 150ºF and pressures ranging between 1000 psig to 4000 psig. An attempt was also made to compare the experimental data with the compressibility factors obtained by the additive volume method. The deviation of the computed compressibility factor from the experimental data was found to be in accordance with the general view of previous workers. However, the deviation was found to be a maximum in the pressure …
Investigation Of The System Al₂O₃-Teo₂-O₂, Vera Zelenkova Sestak
Investigation Of The System Al₂O₃-Teo₂-O₂, Vera Zelenkova Sestak
Masters Theses
"The system Al₂O₃-TeO₂-O₂ has been investigated by X-ray diffraction and differential thermal analysis in air and in sealed silica ampoules. The tellurate, Al₂TeO₆, with tellurium in the +6 valence state, forms in air but not in vacuum at 1 mm pressure. A second phase, a tellurite, possibly Al₂Te₂O₇, forms in air or vacuum by devitrification. The glass-forming region is wider than previously stated and is more extensive in vacuum--from 50% to 98% TeO₂. Tentative phase boundaries have been placed for the system in air and vacuum"--Abstract, page ii.
Fracture Surface Energy Determinations Of High Density Polycrystalline Ceramics, Gene Arthur Pahlmann
Fracture Surface Energy Determinations Of High Density Polycrystalline Ceramics, Gene Arthur Pahlmann
Masters Theses
"Values of fracture surface energy were measured for steatite, zircon, mullite and four densities of alumina. Rods of these high density materials were cut into thin rectangular specimens which were notched and broken in three-point loading. The resulting load necessary for fracture of the specimens was used to calculate the fracture surface energy of the materials. The value for the steatite was around 20,000 ergs/cm². The values for the zircon and mullite were on the order of 13,000 ergs/cm², and the values for the aluminas ranged from 17,000 to 24,000 ergs/cm²"--Abstract, page ii.
Evaluation And Application Of Dye Tracers In Karst Terrain For Determining Aquifer Characteristics, Milton Frank Bradley
Evaluation And Application Of Dye Tracers In Karst Terrain For Determining Aquifer Characteristics, Milton Frank Bradley
Masters Theses
"As ground water becomes increasingly important as a source of water in the United States, reliable information on the hydrological characteristics of carbonate aquifers must be obtained in order to develop them intelligently. Various tracers have been used in the past to determine if two or more points are connected hydrologically. Today there exists a number of excellent dye tracers and tracer methods have been developed in unconsolidated and clastic aquifers for determining hydrological characteristics. This paper reviews the various dye tracers and methods which might be applied in a carbonate karst terrain using wells as injection and sampling points. …
Petrology And Diagenesis Of The Cyclic Maquoketa Formation (Upper Ordovician) Pike County, Missouri, Edwin Carl Kettenbrink Jr.
Petrology And Diagenesis Of The Cyclic Maquoketa Formation (Upper Ordovician) Pike County, Missouri, Edwin Carl Kettenbrink Jr.
Masters Theses
"The Maquoketa Formation (Upper Ordovician-Cincinnatian Series) has been extensively studied for over one hundred years, but a petrographic study of its cyclic lithologies has been neglected. The following six distinct Maquoketa lithologies have been recognized in this study in Pike County, Missouri: 1) phosphatic biosparite, 2) phosphorite, 3) micrite-microsparite, 4) dolomitic shale, 5) dolomitic marlstone, and 6) dolomitic quartz siltstone. Three cycle types are present in the Maquoketa. They are expressed as thin beds (1-20 inches) of alternating micrite-shale, micrite-marlstone, and shale-siltstone. Contacts between different lithologies are sharp, indicating a primary sedimentological origin for the cycles. Precisely what mechanism was …
The Effects Of Magnetic Fields Upon The Steady State And Short Circuit Performance Of Low Voltage Multi-Link Fuses, John Thomas Schultz
The Effects Of Magnetic Fields Upon The Steady State And Short Circuit Performance Of Low Voltage Multi-Link Fuses, John Thomas Schultz
Masters Theses
"The steady state and short circuit performance of multi-link fuses is investigated, as it is affected by the magnetic field of the nearby returning current and the current flowing in the fuse itself. The fuses investigated are low voltage (600 volts or less), multi-link fuses with ratings between 400 and 4000 amperes. The effects of the above mentioned magnetic fields upon the steady state current distribution within the fuse and upon the mechanical forces acting on the individual fuse links are calculated, while the effects of close proximity of the returning current upon short circuit fuse performance are shown by …
A Study Of The Design And Construction Of A Full Scale Aircraft Component Demonstration Fatigue Test, Stephen Andrew Wright
A Study Of The Design And Construction Of A Full Scale Aircraft Component Demonstration Fatigue Test, Stephen Andrew Wright
Masters Theses
"The objective of this project was to design and build a full scale demonstration fatigue test for a Piper Aztec stabilator. A general discussion of the construction is included in this report. The Fourier series method of the aerodynamic theory of spanwise loading was used to determine the load distribution. The results show a close relationship with data furnished by Piper Aircraft Corporation. Fatigue theory is discussed in order to provide background for fatigue testing. The test specimen, methods and procedures of testing, known loading methods and systems, safety, etc., are discussed. Federal requirements for regulating and testing of aircraft …
Spheroidization In Tool Steels, Sharad Gajanan Bankar
Spheroidization In Tool Steels, Sharad Gajanan Bankar
Masters Theses
"A carbon steel, W1, and four other alloy tool steels, namely, A2, H13, D3, and M2, were spheroidized by five different procedures. Any modification made in the treatments for an individual steel were suggested by the results obtained with these five procedures. The hardnesses and microstructures obtained were compared with steel samples annealed at a tool steel mill. The response given by different steels to various methods of spheroidization was studied. It was found that A2, W1, and D3 steels responded the best to the cycling method whereas the best response to the isothermal annealing was given by H13 and …
Effect Of Inclination On Film Boiling, Shih-Chang Lin
Effect Of Inclination On Film Boiling, Shih-Chang Lin
Masters Theses
"The object of this investigation was to determine the effect of inclination on the heat transfer for film pool boiling. The test plate used as the heater was made of Inconel-600 and heated electrically. Liquid nitrogen at atmospheric pressure was used as the test fluid. The heater was oriented at various angles from the horizontal position with the heater surface facing both upward and downward and the heat transfer coefficient was determined for each angle over temperature differences ranging from 450ºF to 750ºF. As the heater angle was increased from 0º (horizontal) to 90º (vertical), the heat transfer coefficient increased …
On-Line Digital Computer Decoding Of Radio Teletype, Julio Alberto Spiegel
On-Line Digital Computer Decoding Of Radio Teletype, Julio Alberto Spiegel
Masters Theses
"Digital computer data processing is one of the newest and fastest growing technologies. The large amount of data that can be processed is practically beyond the limit of human possibilities when available time, cost and reliability of results are taken into consideration. The use of on-line digital computer data processing to decode Radio Teletype is investigated in this thesis. The first part of this thesis considers existing teletype systems and related systems, such as Pulse Code Modulation, pointing out the differences between synchronous and asynchronous codes. The most critical step in decoding Radio Teletype is synchronization, since Radio Teletype makes …
Re-Design Of Cloud Chamber Instrumentation, Stanley Forrest Vaninger
Re-Design Of Cloud Chamber Instrumentation, Stanley Forrest Vaninger
Masters Theses
"Instrumentation and a new valving system is designed and built for use with an expansion type cloud chamber. Digital equipment is used for timing to improve reliability, accuracy, and flexibility, and a servo system is built using a lead compensator circuit which improves the servo system typically used with cloud chambers. Special care was taken to eliminate the sources of noise that appear in the amplified signal from the pressure transducer. The equipment needed to measure, record, and calibrate the pressure inside the chamber is built"--Abstract, page ii.
Modified Method Of Linear Associative Retrieval, James Donald Byrd
Modified Method Of Linear Associative Retrieval, James Donald Byrd
Masters Theses
"It is becoming increasingly important for those in decision making positions to have the most current and accurate data possible as related to their particular needs. Although there are several well known retrieval techniques available an intensified effort is being made at many installations to provide a retrieval system that will supply the demands of their own needs. One well known approach to the solution of information retrieval is linear associative retrieval. The solution that has been proposed requires several computer runs on some requests and therefore is very time consuming. The author has implemented a method to eliminate unnecessary …
An Approximate Min-Max Solution To The Identification Problem, Richard Loyd Warren
An Approximate Min-Max Solution To The Identification Problem, Richard Loyd Warren
Masters Theses
"A technique based on the min-max error criterion is proposed for identifying a dynamic system in terms of a discrete-time model from the system response to a deterministic input. A linear, single-input/single-output, lumped-parameter, time-invariant (at least during the measurement interval) system is assumed. Although the resulting problem is non-linear, it is shown that linear programming techniques are applicable if a realistic approximation is made. The technique is implemented on the digital computer and evaluated by considering a number of typical discrete-time systems. The effects of additive noise are also considered"--Abstract, page ii.
The Effect Of Solvents On The Desorption Of Phenol From Carbon, Robert Harold Pahl
The Effect Of Solvents On The Desorption Of Phenol From Carbon, Robert Harold Pahl
Masters Theses
"The desorption of phenol from active carbon was studied using cyclic and continuous flow desorbers. A wide difference in desorption capabilities was shown among nine solvents. The system employed was complex, with water being present in addition to phenol on the carbon. An attempt to correlate the desorption data with the physical properties of the phenol and solvent and Regular Solution theory are presented. A thermodynamic approach using the linear free energy-enthalpy relationship produced an apparently good correlation of the heat of formation of the phenol-solvent hydrogen bond with the desorption data. This indicates that the desorption of the phenol …
A Proposed Concept For The Rapid Field Design Of Protective Structures, John Ross Childress
A Proposed Concept For The Rapid Field Design Of Protective Structures, John Ross Childress
Masters Theses
"This investigation proposes a simplified concept for the rapid field design of protective structures, subject to attack by conventional artillery rounds, mortar rounds and small rockets. Parameters which should be considered during a rigorous design process are discussed. The number and complexity of these parameters make the rigorous design procedure too unwieldy to be efficiently used, in a limited time period, when materials are not available to comply with Standard Designs. Since the duration of an explosion pulse is very short and uncompacted soil is capable of absorbing explosive energy, this study investigates the theory that adequate protection can be …
A Permeability Scaling Technique In The Numerical Simulation Of Water Coning, Virendra Kumar Dutta
A Permeability Scaling Technique In The Numerical Simulation Of Water Coning, Virendra Kumar Dutta
Masters Theses
"A two-dimensional, two-phase, radial, horizontally layered water coning simulator was programmed for large memory digital computers. A permeability sealing technique is developed which allows the use of large size blocks as production blocks. As a result of this technique large time steps have been used without causing saturation instabilities around the well bore and the permeability scaling technique allows a more realistic simulation of a water cone. The IMPES method is used to calculate pressure and saturation in the system for each finite time step. The behaviour of the simulator is studied for various factors affecting the advance of a …