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Dynamical Analysis Of Infant Social Referencing, Melissa Sue Atkins Aug 2000

Dynamical Analysis Of Infant Social Referencing, Melissa Sue Atkins

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of the present study was to examine relations between joint attention, language, maternal sensitivity, and temperament and the emergence of social referencing in infants and to closely observe variability in social referencing. Five infants, 7 months of age, were observed on a weekly basis for a period of four months. All five infants were engaging in social referencing behavior at the beginning of the study, which is much earlier than the literature indicates; therefore, the onset of the behavior was missed. However, results did indicate variability in social referencing behavior, in that infants referenced more in the laboratory …

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Scale, Ecological Fallacy, And The River Continuum Concept, Hope M. Childers Aug 2000

Scale, Ecological Fallacy, And The River Continuum Concept, Hope M. Childers

Graduate Theses, Dissertations, and Problem Reports (ETD)

Concern over scale is not new, and it is not restricted to geographers. Spatial and temporal scaling is a conceptual and methodological problem for all sciences using geographic information. This paper teases out issues of scale and ecological fallacy from the literature and discusses how these issues influence the applicability of an influential theoretical framework in stream ecology, the River Continuum Concept (RCC). Investigators are faced with decisions regarding scale during sampling location selection, field data capture, and subsequent data interpretation. A thorough understanding of the heterogeneity of stream habitats and the life histories of the organisms being studied could …

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Enhanced Design For Oxy -Fuel Fired Batch Tanks Using Cfd Methods, Guosheng Kang Aug 2000

Enhanced Design For Oxy -Fuel Fired Batch Tanks Using Cfd Methods, Guosheng Kang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Oxy-fuel firing is more energy efficient and environment friendly than conventional air-fuel firing and its application for glass melting has begun since 1990. This technology has been advanced for continuous glass melting furnaces based on continued research and application experiences accumulation, while its application in batch tanks is experiencing a transition period. Batch tanks are commonly used by the hand and art glass companies. Compared to continuous furnaces, a batch tank has smaller size and higher operation temperature. The four primary concerns in the application of oxy-fuel firing in batch tanks are (1) The high flame temperature of oxy-fuel firing …

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Symmetrically Continuous Functions, Marcin Szyszkowski Aug 2000

Symmetrically Continuous Functions, Marcin Szyszkowski

Graduate Theses, Dissertations, and Problem Reports (ETD)

This work is devoted entirely to symmetric continuity and consists of five chapters. Chapter 1 is an introduction. Chapter 2, based on the paper [Sz2], is the main part of this work. In this chapter we generalize classic theorems on functions defined on the intervals to functions defined on arbitrary subsets of the real line. Chapter 3 deals with a weaker condition than symmetric continuity---weak symmetric continuity. It is an extended version of my paper [Sz1]. Chapter 4 is based on the paper [CSz]. Here it is shown that symmetrically continuous functions, although being "close" to continuous functions, may not …

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Reliability-Based Method For Stability Of Mine Entry Design And Evaluation, Zhouming (Victor) Sun Aug 2000

Reliability-Based Method For Stability Of Mine Entry Design And Evaluation, Zhouming (Victor) Sun

Graduate Theses, Dissertations, and Problem Reports (ETD)

Variability in the physical properties of coal/rock is a major source of uncertainty encountered around mining environment. It causes a considerable variation in strength/stress estimations of mining structures when the coal/rock properties are used. Therefore, the conventional safety factor method on stability assessment of mining structures is a special case of the more general probabilistic method in that it assumes the variability of coal/rock properties is zero. Although the use of probability and statistical methods in the analysis and design of geotechnical structures has grown rapidly in recent years, its application to mining structure design has been slow due to …

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Virulence Of Cryphonectria Hypoviruses From Previous Release Sites, Paul Henry Chaloux May 2000

Virulence Of Cryphonectria Hypoviruses From Previous Release Sites, Paul Henry Chaloux

Graduate Theses, Dissertations, and Problem Reports (ETD)

In 1994 and 1995, Cryphonectria parasitica isolates singly or doubly infected with hypoviruses in the CHV3 genus, and lacking distinctive morphological abnormalities, were recovered near plots formerly used to release hypoviruses. This study tested the hypothesis that North American hypoviruses are evolving decreased virulence, and investigated hypovirus interactions affecting virulence in double-infections. Families of single conidial progeny (SCP), differing in infection status, and derived from six recovered, three release, and three comparison isolates were tested in three field experiments. All release isolates and four recovered isolates were debilitated by their CHV3-gh2-type hypoviruses. CHV3-sr2-type hypoviruses never caused debilitation. In family SG3-2 …

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Porosity Distribution Prediction Using Artificial Neural Networks, Fahad Abdullah Al-Qahtani May 2000

Porosity Distribution Prediction Using Artificial Neural Networks, Fahad Abdullah Al-Qahtani

Graduate Theses, Dissertations, and Problem Reports (ETD)

Reservoir characterization plays a very important role in the petroleum industry, especially to the economic success of the reservoir development. Heterogeneity can complicate the evaluation of reservoir properties. Porosity is the primary key to a reliable reservoir model.;Several studies in the literature indicated that accurate evaluation of reservoir properties can be made by the analysis of electric logs. Stringtown oil field in Tyler and Wetzel counties in the northwestern part of West Virginia was selected to conduct this study.;Artificial Neural Networks (ANN) is one of the latest technologies available to the petroleum industry. The objective of this study was to …

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Effect Of Debris-Induced Lift-Off On Magnetic Flux Leakage Inspection Results, Francisco Louis Valentine May 2000

Effect Of Debris-Induced Lift-Off On Magnetic Flux Leakage Inspection Results, Francisco Louis Valentine

Graduate Theses, Dissertations, and Problem Reports (ETD)

Debris is present in all pipelines and has the potential to cause debris-induced lift-off in magnetic flux leakage inspection tools. A test apparatus was developed to qualitatively examine the effect of debris-induced lift-off.;The results of this research indicate that debris-induced lift-off has a detrimental effect on magnetic flux leakage data. This increases the potential of pipeline defects being either undersized or missed.;To reduce or eliminate the effects of debris-induced lift-off, the pipeline should be regularly cleaned. This minimizes the occurrence of large accumulations of debris. If it is determined that debris is present in a pipeline, even in small quantities, …

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Predicting Permeability And Flow Capacity Distribution With Back-Propagation Artificial Neural Networks, Alexis Jose Riera May 2000

Predicting Permeability And Flow Capacity Distribution With Back-Propagation Artificial Neural Networks, Alexis Jose Riera

Graduate Theses, Dissertations, and Problem Reports (ETD)

The prediction of permeability is a critical, key step for reservoir modeling and management of oil recovery operations. Previous studies have successfully demonstrated that the new technology called Artificial Neural Network (ANN), a biologically inspired, massive parallel, distributed information processing system, is an excellent tool for permeability predictions using well log data. This technology overcomes the drawbacks caused by the inherent heterogeneity of the reservoir and lack of sufficient cores or pressure transient tests, allowing to define reservoir characterization within an acceptable accuracy while maintaining costs low. The methodology used in this study takes advantage of this technology to accomplish …

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Iron And Acid Removal From Acid Mine Drainage In Open Limestone Systems, Qingyun Sun May 2000

Iron And Acid Removal From Acid Mine Drainage In Open Limestone Systems, Qingyun Sun

Graduate Theses, Dissertations, and Problem Reports (ETD)

Passive systems, like wetlands, anoxic limestone drains, and open limestone channels, show promise for treating acid mine drainage (AMD) discharges. Open limestone channels have been developed for over ten years and the treatment effectiveness of AMD by open limestone systems shows wide variation. The variation is due to site conditions (slope and size of the limestone channel) but more importantly to the surface area of the limestone and iron concentrations in the water. Iron in AMD coats the limestone in open limestone systems thereby reducing the surface area available for reaction. Over time, the limestone appears to lose its ability …

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Investigating Spelling Through Generative Instruction, Linda Ross May 2000

Investigating Spelling Through Generative Instruction, Linda Ross

Graduate Theses, Dissertations, and Problem Reports (ETD)

The present study examined the components of generative instruction through the teaching of spelling rules. In Experiment 1, the effects of direct versus passive instruction and rate building versus equal-time practice were examined. Forty undergraduate students with below average spelling skills participated. Although there were better performances under passive instruction on some aspects of the posttests, and improved performance with rate-building practice on others, these results were not systematic and were contradicted by other results. The effects of rate building versus an equal amount of practice on the training and posttest application of spelling rules were examined in Experiment 2. …

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Hydrogeologic Analysis Of Streamflow In Relation To Underground Mining In Northern West Virginia, David Robert Gill May 2000

Hydrogeologic Analysis Of Streamflow In Relation To Underground Mining In Northern West Virginia, David Robert Gill

Graduate Theses, Dissertations, and Problem Reports (ETD)

Land subsidence, caused by longwall mining, has a negative effect on overlying watersheds. Nine streams were monitored from their headwaters to their mouths for discharge, temperature, conductivity, alluvium thickness, and alluvium sediment size. Seven streams are located over undermined longwall panels, with two located over non-undermined areas. Discharge data shows that non-undermined watersheds do not experience stream dewatering, regardless of alluvium thickness or sediment size. Streams located over active or recently mined longwall panels experience water loss that ranges from slight to total. Impacted streams with overall increases in conductivity and decreases in water temperature suggest that lost streamflow travels …

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Composition Effects On Macroscopic Solidification Segregation Of Superalloys, Wei Chen May 2000

Composition Effects On Macroscopic Solidification Segregation Of Superalloys, Wei Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research work investigates primarily the composition effects on solidification macrosegregation, i.e. freckles, in superalloys. First, the freckling mechanism of superalloys is developed using the physical simulation of freckle formation in specially designed model alloys. It is found that freckles originate from dendrite irregularities at the solidification front. The freckle channels flow downward in Nb-containing alloys and upward in T-containing alloy under horizontal solidification conditions. The horizontal solidification correctly simulates the horizontal component in remelt ingot where freckling potential is the highest. Based on the result, key control parameters for freckling are identified.;Thermodynamic simulation approach is employed to study the …

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Rollover Stability Of Partially Filled Heavy-Duty Elliptical Tankers Using Trammel Pendulums To Simulate Fluid Sloshing, Mohamed Ibrahim Salem May 2000

Rollover Stability Of Partially Filled Heavy-Duty Elliptical Tankers Using Trammel Pendulums To Simulate Fluid Sloshing, Mohamed Ibrahim Salem

Graduate Theses, Dissertations, and Problem Reports (ETD)

Partially filled tankers undergoing turns or lane change maneuvers have a lower rollover threshold than any other type of vehicle. In order to study and simulate the lateral fluid sloshing effects in partially filled elliptical and cylindrical tankers a trammel pendulum has been utilized. The fundamental basis of selecting the appropriate pendulum parameters have been obtained by matching the pendulum dynamic effects with fluid sloshing dynamic effects obtained using Finite Element (FE) fluid models. Elliptical tankers with different aspect ratios and different levels of fill were considered. The trammel pendulum effects were verified against fluid models from two packages (FLUENT …

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Contrawound Toroidal Helical Antenna Modeling Using The Fdtd Method, Khaled Mohammad Elsherbini May 2000

Contrawound Toroidal Helical Antenna Modeling Using The Fdtd Method, Khaled Mohammad Elsherbini

Graduate Theses, Dissertations, and Problem Reports (ETD)

The contrawound toroidal helical antenna (CTHA) is a patented antenna developed at the Center for Industrial Research Applications (CIRA) of West Virginia University. In this study, a computer numerical model was built to simulate the behavior of printed circuit board versions of the CTHA. The numerical model was built upon the finite difference time domain method (FDTD). The results were compared to results from physical antennas, obtained from the CIRA anechoic chamber located in the WVU hanger, to verify the validity of the results of the numerical model. The results from both the numerical and experimental models were also used …

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Gas Production Forecasting Using Automatic Type Curve Matching, Walter Jonathan Diazgranados May 2000

Gas Production Forecasting Using Automatic Type Curve Matching, Walter Jonathan Diazgranados

Graduate Theses, Dissertations, and Problem Reports (ETD)

As the demand for natural gas has increased in the last years, also the need for forecast reliable gas recoveries. Gas type curves are one of the methods utilized to estimate future well performance. The purpose of this study is the utilization of the Aminian et al type curves to model gas well performance. Unlike other studies developed in the past, Aminian et al type curves account for important factors ignored in the derivation of the proposed theoretical solutions. Thus, the pressure dependency of gas viscosity and compressibility, as well as the pressure loss owing to non-Darcy flow, make of …

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Inventory And Prediction Of Heavy-Duty Diesel Vehicle Emissions, Justin Michael Kern May 2000

Inventory And Prediction Of Heavy-Duty Diesel Vehicle Emissions, Justin Michael Kern

Graduate Theses, Dissertations, and Problem Reports (ETD)

A vehicle emissions inventory is an account of emissions produced by all vehicles in an area. Many different factors can affect the emissions and the measurement of the emissions that are used to create an emissions inventory. These factors for heavy-duty diesel vehicles have been addressed and their relative affect on emissions was evaluated from test data and analytical analyses. These elements can affect the emissions by a factor of 15 depending on testing conditions.;One purpose that an emissions database serves is to provide a source for predicting future emissions for a specific vehicle or many vehicles in a general …

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Evaluation Of Lubricants For Cold Forming Of Steels By Double-Cup Extrusion Tests, Shivakumaran Bharadwaj Venkataraman May 2000

Evaluation Of Lubricants For Cold Forming Of Steels By Double-Cup Extrusion Tests, Shivakumaran Bharadwaj Venkataraman

Graduate Theses, Dissertations, and Problem Reports (ETD)

The double-cup extrusion testing method was chosen for measuring the pressure and material flow parameters in order to quantify the frictional shear factor between the workpiece and the forming tool in cold metal forming processes. The test was adapted to be used under production conditions and applied to characterize and compare the lubrication properties of different types of lubricants and coatings.;It was found to be a useful approach to estimate the relative efficiency of different lubricants and coating methods. It indicated that one specific lubricant has significantly superior lubricant characteristics than others.;FEA analysis of the experimental setup was constructed to …

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Smart Card-Enabled Security Services To Support Secure Telemedicine Applications, Monoreet Mutsuddi May 2000

Smart Card-Enabled Security Services To Support Secure Telemedicine Applications, Monoreet Mutsuddi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Internet is quickly evolving into a standard and widely used mode of information transfer. Therefore internet's information transfer capabilities could be exploited by Secure Telemedicine Applications to securely transfer medical information. However the current day internet protocol stack does not provide much in terms of security for the data being transferred across it. In this thesis we explore how Cryptography along with Smart Cards can be used to implement application layer protocols, to enhance the security of data flowing across the internet in a Secure Telemedicine environment. This thesis also discusses the design and implementation of various system software …

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Designing Neural Networks For The Prediction Of The Drilling Parameters For Kuwait Oil And Gas Fields, Abdulrahman F. Al-Rashidi May 2000

Designing Neural Networks For The Prediction Of The Drilling Parameters For Kuwait Oil And Gas Fields, Abdulrahman F. Al-Rashidi

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study a new methodology was developed to predict the drilling parameters using the Artificial Neural Network. Three models were developed to predict bit type, rate of penetration (ROP), and cost-per-foot (cost/ft), respectively.;The prediction of bit type and other drilling parameters from the current available data is an important criterion in selecting the most cost efficient bit. History of bit runs plays an important factor in bit selection and bit design. Based on field data, the selection of bit type can be accomplished by the use of a neural network as an alternative bit selection method.;Three drilling parameters were …

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Parental Influences On High School Student Achievement And Goals, Richard K. York May 2000

Parental Influences On High School Student Achievement And Goals, Richard K. York

Graduate Theses, Dissertations, and Problem Reports (ETD)

The present study examined parental influences on educational and career goals of high school students. Data on educational and career goals from the Perceived Life Chances Interview were derived from 124 rural adolescents. One hundred of their mothers and 36 of their fathers completed the Inventory of Parental Influence which consists of five subscales of Parental Involvement/Help, Psychological Support, Parental Pressure, Pressure for Intellectual Development, and Time Management/Monitoring. Responses from the Perceived Life Chances Interview were qualitatively analyzed in order to derive categories that reflected the varying responses from participants. These categories served as dependent variables in a series of …

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Effects Of Cumulative Practice On Mathematics Problem -Solving Behavior, Kristin Hobbs Hazlett May 2000

Effects Of Cumulative Practice On Mathematics Problem -Solving Behavior, Kristin Hobbs Hazlett

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mathematics education has long been in need of improved methods of instruction, particularly in the area of problem-solving skills. This study compared three methods of training rules about laws of exponents and order of operations. All three training methods used the same mastery criterion for training each rule and included the same number of practice trials during review sessions that preceded each test. The difference between conditions involved what types of problems were presented during the reviews. For each review session, the cumulative group (n = 11) practiced 50 problems covering all rules learned up to that review. The simple …

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Factors Found When Integrating Computer Technology In A Small Rural School District, Edward Dale Jeffreys May 2000

Factors Found When Integrating Computer Technology In A Small Rural School District, Edward Dale Jeffreys

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this research study was to provide school board members, school administrators, and teachers with information required in developing a successful plan for the integration of computer technology into the classroom curriculum. The stated problem of this research was to identify and analyze the factors that inhibit and enhance the implementation of computer technology into the classrooms of a small rural school district.;A review of the literature was conducted in the following areas: (a) the use of computer technology in K--12 rural school districts; (b) enhancers to the integration of computer technology into the classroom curriculum in small …

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Study Of Human Head Impact: Brain Tissue Constitutive Models., Toru Aida Jan 2000

Study Of Human Head Impact: Brain Tissue Constitutive Models., Toru Aida

Graduate Theses, Dissertations, and Problem Reports (ETD)

Finite element (FE) models of the human head have been used extensively to assess engineering response parameters (pressure, shear strain, etc.) that constitute the basis of various injury criteria including the Head Injury Criterion (HIC). There is a wide range of brain material properties reported in the literature, and linear elastic models are frequently used for the brain tissue which is viscoelastic in nature. The uncertainty around the properties of brain tissue affects the perceived importance of those response parameters under consideration. In this research, the effect on head injury criteria of five reported viscoelastic brain models and their linear …

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Data Points Or Cultural Entities: A Gis-Based Archaeological Predictive Model In A Post-Positivist Framework., Linwood Jesse Rouse Jan 2000

Data Points Or Cultural Entities: A Gis-Based Archaeological Predictive Model In A Post-Positivist Framework., Linwood Jesse Rouse

Graduate Theses, Dissertations, and Problem Reports (ETD)

Archaeological predictive models have been used in conjunction with sampling strategies, in large scale archaeological surveys, for over thirty years. During this time, these models have undergone many conceptual and theoretical changes. Archaeological predictive models stemmed from the positivist Processual Archaeology, but the shift from positivism has precipitated the need to reconsider the ideas from which they are based. There is a general trend within the current spectrum of ideologies to support the importance of cultural information in archaeological research. The following research contends that cultural information has not been utilized to its full extent in archaeological models and that …

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Development Of System Parameters For Enhanced Cutting And Finishing Of Handglass Using A Carbon Dioxide Laser., Christopher Edward Thompson Jan 2000

Development Of System Parameters For Enhanced Cutting And Finishing Of Handglass Using A Carbon Dioxide Laser., Christopher Edward Thompson

Graduate Theses, Dissertations, and Problem Reports (ETD)

In handglass manufacturing, a need has been identified for a more efficient method to crack off glassware. Extended cutting and finishing times and high rates of breakage in the glassware hinder current methods. For example, due to the physical nature of thermal cracking, crack-off is not easily controlled and after separation is achieved, further finishing of the glassware is required. Depending on the glass properties and worker skill level, losses due to breakage can be as high as 80 percent in some product lines. The Laser Glass Cutting Machine (LGCM) is a joint project among the National Energy Technology Laboratory …

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Educators' Views Of Implementing Direct Instruction Curricula: Connections To Students With Disabilities., Brenda Wilson Jan 2000

Educators' Views Of Implementing Direct Instruction Curricula: Connections To Students With Disabilities., Brenda Wilson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to examine the process of the first year of implementation of Direct Instruction curricula as seen through the eyes of the educators implementing it. The study also attempted to determine if general educators' knowledge and use of Direct Instruction techniques while implementing a published curriculum would translate into more effective practices toward students with disabilities in the general education classroom. Seventeen teachers at a small rural elementary school were studied as they implemented Direct Instruction curricula for the first time. The teachers used the Reading Mastery, Corrective Reading and Language for Learning programs published …

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An Exploratory Study Of Policy, Procedures, And Programs For Students With Special Needs Assigned To Alternative Schools In North Central West Virginia., Richard Michael Belcastro Jan 2000

An Exploratory Study Of Policy, Procedures, And Programs For Students With Special Needs Assigned To Alternative Schools In North Central West Virginia., Richard Michael Belcastro

Graduate Theses, Dissertations, and Problem Reports (ETD)

Using an exploratory method this study examined the policies, procedures, and programs for students with special needs assigned to alternative schools in North Central West Virginia. Initially, twelve special education directors in West Virginia's RESA VII were surveyed to determine what approach was being used to serve students with special needs assigned to alternative schools. Four alternative school staffs were selected to be interviewed to determine what were the policies, procedures, and programs in serving students with special needs assigned to alternative schools. Disruptive and at risk students have long presented a dilemma for local school administrators. While trying to …

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Knowledge Acquisition From Video, Video With Animated Graphics, And Laboratory Experience: Predictors For Adolescents With Mild Mental Impairments., John D. Foshay Jan 2000

Knowledge Acquisition From Video, Video With Animated Graphics, And Laboratory Experience: Predictors For Adolescents With Mild Mental Impairments., John D. Foshay

Graduate Theses, Dissertations, and Problem Reports (ETD)

The movement toward assistive technology (AT) and access to the general curriculum provided by the 1997 Amendments to the Individuals with Disabilities Education Act (IDEA) has resulted in the need to study instructional methods that employ computer-based multimedia. Although the definition of AT includes interactive multimedia (Blackhurst, 1997), there has been little research on the use of multimedia to provide access to the general education curriculum. The existing literature has provided a theoretical base and investigated the ability of multimedia presentations to improve academic skills, but has failed to identify instructional practices that promote such access through AT. This dissertation …

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"I'M Right There": Central Appalachian Women In Public School Leadership., Kathy L. Seelinger Jan 2000

"I'M Right There": Central Appalachian Women In Public School Leadership., Kathy L. Seelinger

Graduate Theses, Dissertations, and Problem Reports (ETD)

Despite a deluge of national attention to equity issues, public school administration is still the domain of men. Research attention to women in leadership has done little to close the gender gap in superintendents' and secondary school principals' offices, perhaps because of its focus on successful men rather than on the women who hold these positions. Qualitative interviews examine seven central Appalachian women school leaders in light of feminist standpoint theory, focusing on the way the women enter leadership, articulate a personal construction of the leadership role, and negotiate the borders between their own constructions and the prevailing ones. Profiles …

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