Digital Commons Network^™

Design Of A Microprocessor Controlled Telecommunication System, George J. Maroutsos

Dissertations and Theses

Recent advancements in Large Scale Integration Technology have made available devices, such as microprocessors, analog gates and "three state" logic, that provide the designer with a wide range of possibilities in the design of telecommunication systems. A microprocessor and analog gates are utilized in this design to demonstrate the feasibility of implementing a flexible Telecommunication System. The microprocessor is programmed to control, through software, the system functions. The feasibility of systems highly adaptable to the needs of individual subscribers is thus demonstrated.

Investigation Of Fast Interface States In Mosfets Using A Pulsed Field Effect Technique, Anthony E. Giraudo

Electrical and Computer Engineering ETDs

This thesis is the culmination of an investigation into the pulsed field effect technique. Basically, the pulsed field effect technique is a measurement of the surface conductance of a semiconductor under the influence of a transverse electric field. The pulsed field effect has been used to investigate surface states and interface states at the silicon surface. The nature of this technique allows it to be used in analyzing the metal-oxide-semiconductor field effect transistor (MOSFET). Specifically, the investigation has been to determine if the pulsed field effect technique could be used to investigate fast interface states which are located at the …

Sensitivity Of Process Variables On Rigid Polyurethane Foaming, Bruce A. Pugsley

Theses and Dissertations

Inadequate understanding and/or control of the polyurethane rigid foam process normally requires five to ten percent overpack of cavities to obtain correct fill and foam characteristics. This practice of overpacking has resulted in excessive waste and cost.

A Numerical Solution For The Ultimate Strength Of Tubular Beam-Columns, Arnold L. Wagner

Dissertations and Theses

To provide a basis for the development of interaction curves for tubular beam-columns of annular cross section, a general purpose beam-column computer program is developed, and used to determine ultimate load capacities. The paper presents the analytical model and the computer method. The analytical results are compared with published test data as well as experimental data obtained as part of this project.

An Experimental Study Of Semi-Continuous Ph-Parametric Pumping With A Center Feed, John S. Dell'osso

Theses

Parametric pumping represents a new development in separation science. It has attracted considerable attention both because of its novelty and because it permits continuous operation in small equipment with very high separation factors. The basic principle of parametric pumping is to utilize the coupling of periodic changes in equilibrium conditions caused by periodic changes in some intensive variables (temperature, pH, electric field, etc.), and periodic changes in flow direction to separate the components of fluid which flows past a solid adsorbent. Applications of parametric pumping involving the separation of valuable materials such as proteins would be very attractive and profitable …

Application Of Multilevel Control Techniques To Classes Of Distributed Parameter Plants, Frederick Donald Chichester

Dissertations

This study concerns the application of a combination of multilevel hierarchical systems analysis techniques and Pontryagin's minimum principle (multilevel control) to the problem of controlling optimally two classes of dynamic distributed parameter plants representing concentrations balances in streams, rivers and estuaries. The concentrations treated in this study are those deemed the most effective indicators of water quality, dissolved oxygen (DO) and biochemical oxygen demand (BOD).

One class of plants treated in this study consists of linear continuous distributed parameter plants represented mathematically by sets of simultaneous partial differential equations. Optimal control of a plant of this class is initiated by …

Lumped Parameter, State Variable Dynamic Models For U-Tube Recirculation Type Nuclear Steam Generators, Mohamed Rabie Ahmed Ali

Doctoral Dissertations

A number of lumped parameter dynamic models were developed for a vertical U-tube recirculation steam generator (UTSG) of the type used in most pressurized water reactor nuclear steam supply systems.

The models ranged in complexity from a simplified model (Model A) with only three lumps to represent the primary fluid (reactor coolant), tube metal and the secondary fluid to a detailed model (Model D) with fourteen lumps and a moving boundary between the subcooled and boiling sections of the heat exchange region. The models are linear and are in the state variable form which is convenient for using standard general …

Sodium-Initiated Polymerization Of Alpha-Methylstyrene In The Vicinity Of Its Reported Ceiling Temperature, Shuenn-Long Ou

Dissertations

No abstract provided.

Electronic Contribution To Magneto-Thermoelectric Power In Many-Valley Model Of N-Ge, Carlos Humberto Munera

Masters Theses

No abstract provided.

Ohmic Magnetoresistance In Nonparabolic Semiconductors: Application To N-Insb, Mahmoud Jaafarian

Masters Theses

No abstract provided.

Effects Of Rheology On Pigmented Size Press Coating Pattern, Stanley L. Oakleaf

Masters Theses

No abstract provided.

Elastic-Plastic Analysis Of A Flat Ring Subject To Internal Pressure, Wei-Yang Warren Lu

Mechanical Engineering ETDs

An exact elastic-plastic solution for the stresses in a flat ring subject to pressure is obtained on the basis of J₂ deformation theory together with a modified Ramberg-Osgood law. The results are assessed on the basis of Budiansky's criterion for the acceptability of J₂ deformation theory. By using exact elastic-plastic stresses, the radial enlargement and the permanent increase in thickness of the ring at the hole are obtained. Upon release of the pressure, residual stresses around the hole are produced.

A Study On The Stabilization Of A Floating Platform, Waldo Lizcano

Dissertations and Theses

A new technique for controlling the pitching motion of a floating platform is proposed in this study.

The floating platform is assumed to be a simplified model of the columnar type rectangular platform supported by buoyant force from four cylindrical legs. The control arrangement consists of water jet streams immerging horizontally from two points located some distance apart on each leg to form a restoring couple. The water jet streams can be shifted t0 opposite horizontal positions or to the vertical downward ,positions according to control requirements. They are governed by angle control criterion as well as velocity control criterion. …

The Effects Of Optical Path Perturbations During Recording On A Reconstructed Holographic Image, Stevan Israel Feldman

Dissertations

The effects of optical path perturbations occurring during recording on the reconstructed image of a hologram are investigated. It is shown that such variations of optical path are equivalent to conditions of holographic interferometry which can be classified in three categories: 1) object motion alone, 2) film motion alone, and 3) simultaneous film and object motion; all motions are defined with respect to the stationary reference source during the recording of the hologram.

The theory concerning the effects of object motion alone on the radiance distribution of a reconstructed holographic image has already been developed by previous researchers and is …

Distributed Parameter Sensitivity Theory To Solve Certain Reliability Problems, Moses Nee Buernor Ayiku

Dissertations

It is well known that in actual control systems there are uncontrolled parameter changes caused by aging of elements, temperature, pressure and effects of externalmedium, among others, which may impair the performance ofthe system. Hence, there is the need to develop systems that weakly react to these parameter fluctuations. Sensitivity theory has been developed to study some of these problems. Most of the investigations in this area, however, deal with problems in continuous systems modeled by ordinary differential equations. Even the recent publications on sensitivity problems in distributed parameter control systems are largely concerned with systems modeled by first order …

Investigation And Optimum Design Of The Generalized Second-Order Phase-Locked Loop, William Allen Novick

Dissertations

In this dissertation, a second-order phase-locked loop (PLL) in which the loop filter contains complex zeros is investigated in both its linear and nonlinear modes of operation; prior designs used a filter containing a simple zero on the negative real axis. This "generalized" second-order PLL had been heretofore essentially unexplored.

The basic characteristics of the generalized second-order PLL operating in the linear mode including the open and closed-loop responses and the corresponding root locus were generated and compared against those of the conventional second-order PLL. As in the conventional case, the generalized second-order PLL is found to be unconditionally stable. …

Preparation And Magnetic Properties Of Rare Earth Garnets And Apatites, Rostam Mondegarian

Dissertations

It has been found possible to prepare garnets with magnetic trivalent rare earth ions filling all or most dodecahedral sites while nonmagnetic Sc³⁺ ions fill all octahedral sites and magnetic Fe³⁺ ions fill all or most tetrahedral sites. Phase-pure garnets found include {RE_3-ySc_y}[Sc₂](Fe₃)O₁₂, where RE is Sm, Eu, Gd, Tb or Dy and y can be zero with Sm and Eu; {Nd₃}[Sc₂](Fe_zGa_3-z)O₁₂; and other Nd-Sc-Fe garnets of the type {Nd_3-(w+y)M_wS_cy}[Sc₂](Fe …

Separations Of Multicomponent Mixtures Via Thermal Parametric Pumping, John Daniel Stokes

Dissertations

This dissertation covers the separation of solutes from multicomponent solutions via direct mode thermal parametric pumping.

Dilute solution separations were predicted from existing binary equations by assuming the existence of pseudo binary systems, each system consisting of one solute and the common solvent. Two systems, toluene-aniline-n-heptane and toluene-acetophenone-n-heptane with a silica gel adsorbent were used to experimentally demonstrate the separation. Experimental results were in good agreement with the mathematical predictions.

For concentrated multicomponent solutions, the separation was demonstrated by the system, toluene-acetophenone-n-heptane on silica gel. The effects of mass transfer and nonlinear adsorption isotherms became significant and a numerical solution …

The Effects Of Angularity On The Compaction And Shear Strength Of A Cohesionless Material, Richard Edward Swiderski

Theses

Several physical methods are described for the practical measurement and rating of angularity (shape) of cohesionless soil particles. Angularity is determined by utilizing the fundamental property of a sphere: a sphere has the smallest contact surface area of any shape for a given volume. Therefore, any other shape will exhibit a greater contact surface area and consequently will have a greater frictional resistance which is a function of its degree of angularity.

The effects of angularity on the physical behavior (e.g. strength) of cohesionless soils was investigated at various relative compaction densities. For this purpose a combined compaction and direct …

Prediction And Correlation Of The Salt-Effect In Vapor-Liquid Equilibrium, Enrique M. Bekerman

Theses

The feasibility of developing a method of correlation and prediction, for mixtures of two solvents containing a dissolved salt has been studied. The procedure consisted of arriving at the interaction parameters for the three binary systems (solvent 1-solvent 2, solvent 1-salt, solvent 2-salt) and using these to calculate the ternary results. Attempts to generate interaction parameters for the solvent-salt binaries by means of the Wilson equation were unsuccessful, whereas, use of the NRTL equation resulted in a very good fit of the binary data.

In correlating the ternary results, it became necessary to redefine the liquid phase mole fractions and …

Reaction Kinetics For The Synthesis Of Benzyl Benzoate From Benzyl Chloride And The Triethylamine Salt Of Benzoic Acid, Michael A. Kolakowski

Theses

The reaction kinetics for the synthesis of benzyl benzoate from benzyl chloride and the triethylamine salt of benzoic acid has been studied over the temperature range of 70-105°C and a mole ratio of benzyl chloride to triethylamine of 0.5 - 10.0.

A reaction mechanism which is consistent with the experimental data has been derived. The experimental data was analyzed by means of the integral method of analysis. The temperature dependency of the reaction was determined from Arrhenius' Law and the activation energy was calculated to be 15,064 cal/g-mole. An empirical equation which explains the effects of the reactant mole ratio …

Subcontracting By The Petrochemical Engineer-Constructor, Michael Peter Skurla

Theses

An analysis has been made of the methods used by a Petrochemical Engineer-Constructor, who has national labor agreements, in deciding if the construction phase of a project should be done by a subcontract method of construction or be accomplished on a direct hire basis. The petrochemical complex under discussion is considered to be in the $75 million range for the total installed cost including design, engineering, procurement, and construction.

The influence of subcontracting portions of the construction phase by the Engineer-Constructor is reviewed with its impact on: the client; project schedule and cost; local and national labor relations, because of …

The Recovery Of Methanol From The Mother Liquor Of A Pharmaceutical Active Ingredient, Richard Lawrence Eichholtz

Theses

The company has been sending to the sewer the filtrate from one of our chemical processes. This filtrate contains 63 vol. % methanol. The recovery of this methanol would reduce the amount of purchased methanol. The recovery would also reduce the Biological Oxygen Demand of the plant effluent. In the near future the local sewer authority will be billing the company for BOD.

The goal of the recovery process is to obtain methanol of satisfactory quality for reuse in the process from which it came. A literature search and a laboratory study verified the non-ideality of the system. Preliminary calculations …

Non-Standard Workweek Scheduling Technique Selection, John Alexander Oak

Theses

This thesis presents a description of non-standard work scheduling techniques and a comparison method which enables decision-makers to differentiate between available work-scheduling alternatives with the purpose in mind of selecting the most appropriate and suitable arrangement. The method developed calls for the decision-maker to follow a five-step sequential process to obtain final results. The ingredients necessary to achieve such final results are obtained in a manner similar to that demanded by decision-making-under-uncertainty conditions commonly followed in actual industrial settings.

Since the primary objective of business management is the achievement of a profit through the manipulation of available resources, initial sections …

The Analysis Of The Deflection And Containment Of A Hot Plume By Side Draft Exhaust Hooding, Douglas H. Macgowan

Dissertations and Theses

A common industrial ventilation and pollution problem results when a thermally buoyant polluted plume of air must be exhausted away from a work area to allow achievement of air pollution standards. Generally, a close fitting canopy hood is one of the most effective means of exhaust containment; however, physical restrictions or the operation itself often prevent such an arrangement, and a hood located to the side of the operation is required. This arrangement requires the exhaust to bend and contain the vertically rising plume with a horizontal sweep of exhaust air across the surface of the operation.

A review of …

Evaluation Of The Institute Of Transportation Engineers Program For School Pedestrian Crossing, Nabil Shafiq Hamadeh

Dissertations and Theses

The Technical Council of the Institute of Transportation Engineers (ITE) developed a program for school crossing protection. The intent of this thesis is to evaluate the ITE program within. the context of those programs developed by other agencies throughout the nation. Research materials were obtained from the appropriate Federal, state, local and other agencies through papers, articles, reports and correspondence. Upon the analysis of these sources, the ITE program was found to be deficient in several ways. Recommendations for modifying the program which are set forth herein include a revision of the ITE program including the school route map, clarification …

Bayesian Inquiry: An Approach To The Use Of Experts, King G. Yee

Dissertations and Theses

Subjective information is a valuable resource; however, decisionmakers often ignore it because of difficulties in eliciting it from assessors. This thesis is on Bayesian inquiry and it presents an approach to eliciting subjective information from assessors. Based on the concepts of cascaded inference and Bayesian statistics, the approach is designed to reveal to the decision-maker the way in which the assessor considers his options and the reasons he has for selecting particular alternatives. Unlike previous works on cascaded inferences, the approach here focuses on incoherency. Specifically, it employs the use of additional information to revise and check the estimates. The …

The Design Of An Automatic Electronic Preanodizer, Armen C. Grossenbacher

Dissertations and Theses

The topic of this thesis is the design of an automatic preanodizer to be used to preadjust precision tantalum resistors by anodizing their surfaces. The purpose of the preanodizer is to generate a controllable voltage ramp to be applied to a set of tantalum resistors which are immersed in a suitable electrolyte. The slope and maximum value of the voltage ramp are set to produce the current required for proper anodization of the resistors. The rate of anodization determines the rate of change of the resistor value. This thesis covers the design of an electronic device to meet a set …

Development Of A Water Quality Model Applicable To Great Salt Lake, Utah, Craig T. Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The development of a model capable of predicting the long term (seasonal) distribution of water quality constituents within Great Salt Lake was undertaken as a portion of the ongoing Great Salt Lake project at Utah State University. The overall goal of the project is the development of a modeling framework to assist the relevant decision making bodies in the comprehensive management of the Great Salt Lake system. Phase I of the project provided the overall structural framework for management of the Great Salt Lake system, identified data needs, and established priorities for the development of submodels for incorporation into the …

Effects Of Heavy Metals (Cadmium, Copper, And Mercury) On Reproduction, Growth, And Survival Of Brine Shrimp (Artemia Salina) From The Great Salt Lake, Karl A. Gebhardt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this paper is to report findings concerning the effects of cadmium, copper, and mercury on the brine shrimp Artemia Salina, of the Great Salt Lake. Metal toxicity was observed in relation to acute susceptibility, growth, reproduction, and hatching of the brine shrimp.

Heavy metal concentrations such as cadmium, copper, and mercury are known to be considerably higher in the Great Salt Lake than those in both freshwater and seawater. No published study has been concerned with heavy metal effects on organisms in salinities greater than seawater (35 grams per liter total dissolved solids). The experiments reported …