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The Potential Impact And Optimal Adjustment Associated With An Aluminum Supply Restriction: A Case Study Of Taiwan, Chia-Yon Chen
The Potential Impact And Optimal Adjustment Associated With An Aluminum Supply Restriction: A Case Study Of Taiwan, Chia-Yon Chen
Graduate Theses, Dissertations, and Problem Reports (ETD)
There is a growing concern over the impact of critical mineral supply restrictions on the economies of mineral importing nations such as Taiwan. The objective of this dissertation is to build a framework that can be used to analyze the impact of a supply restriction and that can be used to formulate an optimal adjustment pattern for a national economy. The study contains several important advances over previous studies of the impact of a commodity supply restriction. First, the model presented here generalizes I-O analysis via a linear programming (LP) framework in order to simultaneously handle the production function and …
Structural Design Guidelines For Longwall Panel Layout., Sui-Min Hsiung
Structural Design Guidelines For Longwall Panel Layout., Sui-Min Hsiung
Graduate Theses, Dissertations, and Problem Reports (ETD)
Successful longwall mining requires a good roof control. A good roof control implies that: (1) no excessive pressue is built up in the face powered supports, and (2) chain pillars are designed in such a way that panel entries are well protected and interactions between adjacent panels are minimized. A clear understanding of strata behavior around longwall panels due to face movement is, therefore, the foremost requirement for achieving better roof control. This dissertation is designed to analyze the effects of strata behavior on longwall panels due to the mining activities. The following topics are studied: (1) the weighting phenomena …
Analysis Of Raw Material Extraction Through Simulation: A Timber Harvesting Example (Forest Engineering, Production Planning, Logging)., Leonard Roy Johnson
Analysis Of Raw Material Extraction Through Simulation: A Timber Harvesting Example (Forest Engineering, Production Planning, Logging)., Leonard Roy Johnson
Graduate Theses, Dissertations, and Problem Reports (ETD)
Raw material extraction processes face problems that differ from those encountered in most production systems. Production steps are often quite simple, but material handling and inprocess inventory are complicated by a constantly changing environment. The factory that delivers raw materials must be mobile and flexible to handle variations that occur in the raw material environment. Techniques used to analyze problems common to factories at fixed locations are often inappropriate for extraction processes. A simulation model of the extraction process can be used to provide input to many production planning steps. It should consist of three components. The production process can …
Multivariable System Identification Coal Gasification Process., Ali Reza Delavari
Multivariable System Identification Coal Gasification Process., Ali Reza Delavari
Graduate Theses, Dissertations, and Problem Reports (ETD)
Obtaining information on the dynamic behavior of a system or process for ultimate use in control strategies is essential. Identification of a system in real time is divided into two areas, parametric and non-parametric. In the non-parametric method a model is not assumed for the system, while in the parametric method a prior assumption of a given model form with unknown parameters is necessary. The objectives of this research are: (a) Detail studies of various methods of parametric identification in transfer function form, developing and extending some of these methods and a new method for multivariable discrete-time systems. Many criterions …
Evaluation Of Rock Phosphate And Fly Ash Amendments To Ameliorate Toxic Condition In Acid Mine Soils For Crop Production., Hussein Eisa Ghazi
Evaluation Of Rock Phosphate And Fly Ash Amendments To Ameliorate Toxic Condition In Acid Mine Soils For Crop Production., Hussein Eisa Ghazi
Graduate Theses, Dissertations, and Problem Reports (ETD)
A greenhouse investigation was conducted with corn and alfalfa to evaluate rock phosphate (rock-P) and fly ash as amendments to ameliorate toxic conditions in three acid mine soils. The extremely acid mine soils from Valley Point (VP), Westover (WO), and Lenox (LX) were each mixed with fly ash at a rate of 0%, 33% or 67%, and with rock-P at a rate of 0, 10, 20 or 40 g/kg soil in a factorial combination. In a corollary experiment, rock-P was replaced with fertilizer consisting of monocalcium phosphate (200 kg P/ha), KNO(,3) and KCl (112 kg/ha), calcium carbonate (225 kg Ca/ha), …
The Influence Of A Thermal Oxide Layer On Short-Term Degradation Of Silicon Mis Solar Cell Output., Abdul Rahman Alamoud
The Influence Of A Thermal Oxide Layer On Short-Term Degradation Of Silicon Mis Solar Cell Output., Abdul Rahman Alamoud
Graduate Theses, Dissertations, and Problem Reports (ETD)
Metal-semiconductor (Schottky-barrier) solar cells have lower open-circuit voltage than p-n junction solar cells. The open-circuit voltage of a Schottky-barrier solar cell can be increased by the use of an ultrathin oxide layer between the metal and the semiconductor. Fabrication and testing of MIS solar cells with steam-grown oxide layers shows that short-term degradation occurs (within six weeks) and is indicated by lowering maximum power output. Degradation occurs independent of environmental conditions. Auger Electron Spectroscopy (AES) depth-profiles show that degradation is due to growth of a metal-oxide layer at the metal-SiO(,2) interface. This process occurs in a few weeks; with high …
A Reassessment Of Julian Hawthorne Through Consideration Of His Short Fiction, John William Teel
A Reassessment Of Julian Hawthorne Through Consideration Of His Short Fiction, John William Teel
Graduate Theses, Dissertations, and Problem Reports (ETD)
Julian Hawthorne, the son of Nathaniel Hawthorne, was once a popular writer whose fictional works include twenty-four novels and over eighty short stories. Though he was highly regarded by many critics in his time, he is little known today, even among scholars specializing in American literature. The few studies of Hawthorne written in this century generally concur with an opinion commonly expressed by Hawthorne's contemporaries: that he wrote too rapidly to produce carefully crafted novels though he was more successful with his short stories and novellas. Most of his stories have never been collected or anthologized, however, so there has …
Prediction Of Surface Subsidence Profile Due To Underground Mining In The Appalachian Coalfield., Kewal Krishan Kohli
Prediction Of Surface Subsidence Profile Due To Underground Mining In The Appalachian Coalfield., Kewal Krishan Kohli
Graduate Theses, Dissertations, and Problem Reports (ETD)
Subsidence engineering is becoming an important aspect of mine planning in the United States due to Surface Mining Reclamation Act of 1977 which became effective on July 1, 1983. This dissertation contains complete field subsidence data for 42 sites in the Northern Appalachian Coalfield. Five well-known empirical methods were used to predict the subsidence profile, and the predicted profiles were compared with observed profiles. It was found that Hyperbolic Function method could predict within 15% of the observed profiles in the critical zone for this region. Seven two-dimensional finite element models were used to predict the subsidence and the subsidence …
An Analysis Of Learning Styles Of Registered Nurse Students, Basic Nursing Students, And Nurse Educators In A Baccalaureate Nursing Program., Margaret Ann Marcinek
An Analysis Of Learning Styles Of Registered Nurse Students, Basic Nursing Students, And Nurse Educators In A Baccalaureate Nursing Program., Margaret Ann Marcinek
Graduate Theses, Dissertations, and Problem Reports (ETD)
There were two purposes of this study. The primary purpose was to determine if a significant difference in learning styles exists among registered nurse students, basic nursing students, and nurse educators in a baccalaureate nursing program. The secondary purpose was to determine the effects of the following variables on learning style: basic educational preparation in nursing, practice setting, and years of practice in nursing. Kolb's Learning Style Inventory and a demographic data questionnaire were administered to all registered nurse students at the beginning of their first course upon entering West Virginia University. The same tools were administered in a classroom …
Prediction Of Liquid Recovery From A Gas Condensate Reservoir., Jaber A. Almarry
Prediction Of Liquid Recovery From A Gas Condensate Reservoir., Jaber A. Almarry
Graduate Theses, Dissertations, and Problem Reports (ETD)
The primary purposes of this research are to (1) predict the behavior of gas condensate reservoirs, and (2) predict the recovery of liquid hydrocarbons from these reservoirs. Factors involved in liquid recovery are fluid phase behavior (retrograde condensation and liquid revaporization), reservoir heterogeneity, perforation strategies, gas injection versus depletion, cross flow between reservoir layers, injection gas fingering, and pattern geometry. First factor is extremely important to predicting liquid recovery from a gas condensate reservoir. In order to evaluate fluid phase behavior, an equation of state material balance compositional model was developed to simulate the condensate liquid recovery from laboratory constant …
Coal Mine Productivity Assessment As Influenced By Equipment Reliability And Availability., Francisco Lopez Viray
Coal Mine Productivity Assessment As Influenced By Equipment Reliability And Availability., Francisco Lopez Viray
Graduate Theses, Dissertations, and Problem Reports (ETD)
Feasible methods, measures and models which can be used to assess the availability of a continuous mine system are developed. The models, based on a simplified representation of room-and-pillar mining, are derived using the principles of Markov processes. A new measure of system reliability and performance, called the penalized availability is defined. This measure can be applied to any process flow system whose output may be derated due to failures of certain components. Three reliability indices which measure coal productivity in terms of equipment reliability and maintainability are defined. These indices are linearly related to the penalized availability by such …
Electromagnetic Geophysical Tomography Incorporating Refraction And Reflection., Roger Dale Radcliff
Electromagnetic Geophysical Tomography Incorporating Refraction And Reflection., Roger Dale Radcliff
Graduate Theses, Dissertations, and Problem Reports (ETD)
An accurate technique for remotely determining the internal structure of an object or underground environment would have a significant impact in mining, geoexploration, and the life sciences. This process of resolving the intrinsic properties of an object or environment by the transmission of X-rays or electromagnetic waves through the unknown anomaly is known as reconstructive imaging or tomography. Several efforts have been made to apply tomographical methods to electromagnetic measurements taken between two boreholes on either side of an unknown geophysical structure. However, it became necessary, because of the nature of existing reconstruction methods, to assume a straight-line propagation path …
Power Determination For Mobile Mining Equipment., Gene Thomas Lineberry
Power Determination For Mobile Mining Equipment., Gene Thomas Lineberry
Graduate Theses, Dissertations, and Problem Reports (ETD)
A piece of mobile mining equipment must possess sufficient power to overcome normal resistances and also resistances whose prediction and quantification is much more difficult, such as those accompanying cyclic maneuvers and emergencies. These abnormal, highly variable resistances require a quantity of reserve power. The sum of reserve power, required power, auxiliary power, and ambient corrections represents the total power requirement. Reserve power is traditionally defined as "the additional power available to a vehicle for climbing grades and for acceleration." In this study, reserve power was redefined as "the power available to a vehicle in addition to that necessary to …
Simulation Of Hydraulic Fracturing Of Coal., Subhotosh Khan
Simulation Of Hydraulic Fracturing Of Coal., Subhotosh Khan
Graduate Theses, Dissertations, and Problem Reports (ETD)
The parameters affecting the hydrofracturing of coal were investigated through laboratory experiments and theoretical analyses. Effects of (i) fluid flow rate, (ii) confining stresses, (iii) orientation of material axes, and (iv) fluid viscosity were studied experimentally. Equations relating the ultimate tensile strength of coal as a function of confining stresses were developed. The expressions for crack tip stresses around a crack in an anisotropic material were used along with the results of previously performed experiments to show that the maximum normal stress criterion should be used in the fracture mechanics model of Pittsburgh coal. A computer simulation technique for crack …
The Development Of A Computer-Assisted Vocational Guidance System For Use In Rehabilitation Counseling., George Muir Mcguire
The Development Of A Computer-Assisted Vocational Guidance System For Use In Rehabilitation Counseling., George Muir Mcguire
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this study was to accomplish two specific goals: (1)The selection and field-evaluation of a vocational abilities test and an occupational interest test for use as client assessment instruments to aid in the vocational planning stage of the rehabilitation process, and (2)the construction of a computerized vocational guidance delivery system based upon the interest and abilities tests which were selected in the fulfillment of Goal 1. In accomplishing the first goal, the selection of the tests was done by a careful evaluation of Vocational Rehabilitation practices through an extensive literature review and firsthand observation of these practices in …
The Industrial Archeology Of The Shepherdstown, West Virginia Site As A Case Study Of The Natural Cement Industry Of The Upper Potomac Valley., Thomas Frederick Hahn
The Industrial Archeology Of The Shepherdstown, West Virginia Site As A Case Study Of The Natural Cement Industry Of The Upper Potomac Valley., Thomas Frederick Hahn
Graduate Theses, Dissertations, and Problem Reports (ETD)
This dissertation is a case study of the natural cement plant in Shepherdstown, (West) Virginia. The model of the dissertation is industrial archeology, that is, the recording and interpretation of individual industrial sites. The purpose of the study is to show how the case study in the context of industrial archeology can have a useful place in the social studies classroom by bringing students into closer contact with those who lived and worked at a particular place at a particular point in time. As early as 2450 B.C., engineers and builders used cement mortar in domestic buildings and monumental works. …
A Historical Analysis Of The West Virginia College Of Graduate Studies From 1958 To 1976: The Study Of Organizational Birth, Growth And Development., Graydon Gray Williamson
A Historical Analysis Of The West Virginia College Of Graduate Studies From 1958 To 1976: The Study Of Organizational Birth, Growth And Development., Graydon Gray Williamson
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this study was to examine the little-known phenomenon of organizational birth, growth and development through the analysis of a microcosm organization: the West Virginia College of Graduate Studies. The study was not a history, although constructing a history of the organization was necessary in order to provide a base line upon which to plot impact points which were significant to the development of the organization. The study involved an analysis of written material, including legislation directly or indirectly impacting upon the organizational subject of this study. The major method of this study, however, required in-depth interviews with …
Algorithms For An Automatic Mine Ventilation System., Kwai Yeung Lee
Algorithms For An Automatic Mine Ventilation System., Kwai Yeung Lee
Graduate Theses, Dissertations, and Problem Reports (ETD)
A mine-wide algorithm for ventilation control has been developed. This algorithm is suitable for use in an underground coal mine equipped with a distributed microprocessor monitoring and control system. It provides a guideline for installing monitoring devices and remotely controlled air regulators. If some airways need certain amounts of air flows, the algorithm will compute the adjustments on all regulators and fans so that desirable air flow can be directed to those airways. The development, assumptions, limits, and system requirements of the algorithm are presented. A section algorithm for control of gas concentration in an airway has been developed. This …
Dynamic Responses Of A Multi-Layered Rectangular Plate On Viscoelastic Foundation Due To Moving Loads., Cheng-Jer Lin
Dynamic Responses Of A Multi-Layered Rectangular Plate On Viscoelastic Foundation Due To Moving Loads., Cheng-Jer Lin
Graduate Theses, Dissertations, and Problem Reports (ETD)
The Investigation presents the formulation of a general equation of motion and its analytic and numerical solution for the determination of the dynamic deflections and stresses of a multilayered rectangular plate on viscoelastic foundation subject to a constant force travelling at a constant velocity. Various combinations of simply-supported, clamped, and free edge conditions of the plate are studied. A multi-layered plate has in general two shifting "neutral" planes, one in which ax«=0 while OyfQ and another, 0y“O while Oj^O. They are not only at different locations, but also change their locations in the plate depending on the loads or curvatures …
A Free-Vortex Model With Numerical Solution For The Unsteady Lifting Characteristics Of Straight Bladed Darrieus Wind Turbines., Paul Gerald Migliore
A Free-Vortex Model With Numerical Solution For The Unsteady Lifting Characteristics Of Straight Bladed Darrieus Wind Turbines., Paul Gerald Migliore
Graduate Theses, Dissertations, and Problem Reports (ETD)
A method has been developed to analyze the flow and predict the lifting characteristics of vertical axis wind turbines. Blades are modelled by a number of discrete bound vortices located on the airfoil mean camber line; the wake is modelled by a number of discrete vortices shed from the blade trailing edge. Application of the flow tangency boundary condition and the Kutta condition permit a numerical solution for the strengths of the bound vortices. Blade forces are then determined from potential theory. This vortex model faithfully reflects the important phenomena of flow unsteadiness and wake/blade interaction. Wake details and energy …
Simulation Of Fluidized Bed Coal Combustors., Renga Rajan
Simulation Of Fluidized Bed Coal Combustors., Renga Rajan
Graduate Theses, Dissertations, and Problem Reports (ETD)
I t is the aim o f th e p re se n t work to reduce th e se d e fic ie n c ie s , and to form ulate a comprehensive FBC model ta k in g in to account th e follow ing elem ents which were e ith e r p a r t i a l l y considered o r n o t considered a t a l l in the previous work. (1) D e v o la tiliz a tio n o f coal and th e subsequent combustion o …
United States Policy Toward Okinawa, 1945-1972. A Study In Organizational Interaction In Policy-Making., Albert Seigal
United States Policy Toward Okinawa, 1945-1972. A Study In Organizational Interaction In Policy-Making., Albert Seigal
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this study is four-fold: (1) to survey the changes in the United States' policy toward Okinawa from 1945 to 1972; (2) to examine the changing balance of strategic and military requirements which influenced those changes throughout the period being considered; (3) to examine and analyze the bureaucratic interaction of the State Department and the military; and (4) to analyze the results of that interaction in terms of changing strategic requirements.
The Optimal Design Of Electrical Power Plant Facilities Utilizing An Underground Air Storage System., Mihir Kumar Sinha
The Optimal Design Of Electrical Power Plant Facilities Utilizing An Underground Air Storage System., Mihir Kumar Sinha
Graduate Theses, Dissertations, and Problem Reports (ETD)
Cost engineering models have been developed for the preliminary design analysis and evaluation of an underground compressed air storage system for use in conjunction with conventional base-load (coal-steam) electric power generation stations. Models for industrial fuel gas storage systems for peaking application and a total system model for integrated power systems have also been developed for the purpose of preliminary design analysis and evaluation. These models determine the minimum cost of electric power, required capacities of base-load(coal-fired) plant and peaking plants from given values of the total demand, peak demand and fuel costs, as well as characteristics of underground storage …
Structural Mechanics Simulations Associated With Underground Coal Gasification., Yang-Tai Thomas Lin
Structural Mechanics Simulations Associated With Underground Coal Gasification., Yang-Tai Thomas Lin
Graduate Theses, Dissertations, and Problem Reports (ETD)
This study describes analytical simulations of the structural and thermal responses associated with the Longwall Generator concept of underground coal gasification (UCG). The work includes characterization of the mechanical properties of coal and shale overburden at elevated temperature, preliminary thermal and structural response modeling, finite element model formulations, and master model analysis. The characterization of mechanical properties of coal and shale overburden includes thermorheological representation of Pittsburgh coal and shale overburden at elevated temperature and the swelling characteristics of bituminous coal. For the preliminary thermomechanical modeling, dynamic thermal and stress response solutions are obtained for boundary value problems representing a …
Kinetics Of Char Reaction With Carbon-Dioxide - Carbon-Monoxide Gas Mixtures., Ashok Kumar Agarwal
Kinetics Of Char Reaction With Carbon-Dioxide - Carbon-Monoxide Gas Mixtures., Ashok Kumar Agarwal
Graduate Theses, Dissertations, and Problem Reports (ETD)
The work described in this dissertation has been a fundamental experimental study of char reactivity. The effects on char reactivity of CO inhibition, surface area development, particle size, pyrolysis conditions and catalytic effects of Char-CO2-CO reaction have been examined.
Available Work Energy And Coal Conversion Processes., Chun Yen Lin
Available Work Energy And Coal Conversion Processes., Chun Yen Lin
Graduate Theses, Dissertations, and Problem Reports (ETD)
This study examines the available work energy for coal conversion processes as derived from the second law of thermodynamics. The concept of available work energy can provide the relationship between operating conditions and useful energy recovery; while the total energy based on the first law of thermodynamics can establish the relationship between quantities of heat and work energy. The concept of total energy recovery and the available work energy loss is applied to each of the process units in various coal conversion processes. The coal conversion processes which were studied include those which produce synthetic crude oil, pipeline gas, methanol …
Electromagnetic Wave Propagation Within A Subsurface Coal Seam For In Situ Gasification Application., John Joseph Holmes
Electromagnetic Wave Propagation Within A Subsurface Coal Seam For In Situ Gasification Application., John Joseph Holmes
Graduate Theses, Dissertations, and Problem Reports (ETD)
The development of an efficient underground coal gasification process may become an important step in achieving energy selfsufficiency. To realize the benefits of the underground coal gasification process, an electromagnetic monitoring system must be developed to convey information about the status of the gasification process. To aid in the design of the monitoring system an electromagnetic model of the underground coal gasification process is formulated, which will prove beneficial in the saving of time and cost in the research and development stages of the system. Two types of electromagnetic systems are investigated analytically and proposed for the monitoring of the …
Collective Bargaining In Pennsylvania's Public Schools., Roy Evans Brant
Collective Bargaining In Pennsylvania's Public Schools., Roy Evans Brant
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this study was to test the hypothesis that collective bargaining is a viable alternative to unilateral policy making by boards of education in Pennsylvania's public schools. Corollary hypotheses tested were that teacher participation in some traditional management functions is beneficial and that a limited right to strike is necessary to make the collective bargaining process work. Testing the feasibility of the limited right to strike required an examination of the means of impasse resolution, the costs of strikes and the effectiveness of the limited right to strike
Sylvanus Thayer: A Biography., James William Kershner
Sylvanus Thayer: A Biography., James William Kershner
Graduate Theses, Dissertations, and Problem Reports (ETD)
This dissertation attempts to follow the life and career of General Sylvanus Thayer, from his birth in Braintree, Massachusetts in 1785 to his death there in 1872. By placing Thayer with in the proper historical context, it is possible to draw certain conclusions concerning the significance of his achievements in the fields of technical education and military engineering. Since this is a chronological study of Thayer’s life, particular emphasis is given in the first four chapters to the men, events , and influences that shaped his life prior to 1817: family background and early home life ; education at Dartmouth …
Mechanical Properties Of The Pittsburgh Coal At Elevated Temperatures., Harold Dee Shoemaker
Mechanical Properties Of The Pittsburgh Coal At Elevated Temperatures., Harold Dee Shoemaker
Graduate Theses, Dissertations, and Problem Reports (ETD)
While certain rheological-structural properties of some coals have been determined at elevated temperatures, Insufficient data exists to realistically characterize the structural behavior of coal under in situ gasification conditions. Much of the data available is for crushed, crushed and compressed, or otherwise modified conditions of coal from its natural state. The stresses and displacements due to the in situ gasification process and its gradients in the tectonic stress field vary over a wide range of values, thus necessitating the determination of the thermoviscoelastic properties of the Pittsburgh coal. The objectives of this research are: — Determine the mechanical properties (E, …