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A Regional Scale Steady-State Groundwater Flow Model Of A Steeply-Dipping Karst Aquifer, Shenandoah Valley Of West Virginia-Virginia., Jason S. Early Jan 2005

A Regional Scale Steady-State Groundwater Flow Model Of A Steeply-Dipping Karst Aquifer, Shenandoah Valley Of West Virginia-Virginia., Jason S. Early

Graduate Theses, Dissertations, and Problem Reports (ETD)

A regional equivalent porous medium (EPM) model was developed using available hydrogeologic data for the steeply-dipping karst aquifer of the Northern Shenandoah Valley of West Virginia and Virginia. The model employed uniform recharge and variable hydraulic conductivity (K) distributed at the formation level based on published field-test estimates. Three independent procedures were used for calibration, with the most acceptable approach using calibration to heads at wells and specified fluxes for springs. Although this procedure produced a reasonable regional head distribution and acceptable calibration statistics (mean error = 0.58 m, mean absolute error = 8.61 m), the use of specified fluxes …

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Assessment Of Constructibility And Serviceability For Straight And Skewed Steel I-Girder Bridges., Andrew Hayes Jan 2005

Assessment Of Constructibility And Serviceability For Straight And Skewed Steel I-Girder Bridges., Andrew Hayes

Graduate Theses, Dissertations, and Problem Reports (ETD)

Recent changes to the AASHTO specifications for steel bridge design have incorporated specific provisions for handling lateral flange bending in I-shaped steel girders. The primary reason for the inclusion of this effect is to allow for a unification of design provisions for both straight and curved girders. In tangent bridges and in bridges with a small degree of skew the influence of lateral flange bending in the fully composite condition in positive bending are negligible. This is predominantly due to restraint offered by the deck and the diaphragm action offered by the deck in lateral load events. However, during construction …

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Estimation Of Image Quality Factors For Face Recognition, Akintunde A. Akinbola Jan 2005

Estimation Of Image Quality Factors For Face Recognition, Akintunde A. Akinbola

Graduate Theses, Dissertations, and Problem Reports (ETD)

Over the past few years, verification and identification of humans using biometric has gained attention of researchers and of the public in general. Face recognition systems are used by the public and the government and are applied in different facets of life including security, identification of criminals and identification of terrorists. Because of the importance of these applications, it is of great necessity that face recognition systems be as accurate as possible. Some research has shown that image quality degrades the performance of face recognition systems. Most previous research has focused on designing algorithms for face recognition that deal or …

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Evaluation Of Quality Control Parameters For Superpave Hot Mix Asphalt, Thomas W. Adams Jan 2005

Evaluation Of Quality Control Parameters For Superpave Hot Mix Asphalt, Thomas W. Adams

Graduate Theses, Dissertations, and Problem Reports (ETD)

Quality control of Superpave hot mix asphalt has profound consequences for both the West Virginia Department of Highways (WVDOH) and the constructor who has placed the asphalt. The quality control procedure includes taking samples from the job site, and performing various tests so that certain volumetric parameters can be evaluated against a standard set of tolerances. WVDOH currently uses a statistically based quality control - quality assurance method, QC/QA.;The current QC/QA requirements used by the WVDOH for Superpave projects have not been statistically evaluated to establish the risk to the agency and constructor for either accepting an unsatisfactory material or …

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Graph Algorithms For The Haplotyping Problem, Yunkai Liu Jan 2005

Graph Algorithms For The Haplotyping Problem, Yunkai Liu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Evidence from investigations of genetic differences among human beings shows that genetic diseases are often the results of genetic mutations. The most common form of these mutations is single nucleotide polymorphism (SNP). A complete map of all SNPs in the human genome will be extremely valuable for studying the relationships between specific haplotypes and specific genetic diseases. Some recent discoveries show that the DNA sequence of human beings can be partitioned into long blocks where genetic recombination has been rare. Then, inferring both haplotypes from chromosome sequences is a biologically meaningful research topic, which has compounded mathematical and computational problems.;We …

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Gallium Nitride-Based Blue Laser Diodes, Sridhar Kuchibhatla Jan 2005

Gallium Nitride-Based Blue Laser Diodes, Sridhar Kuchibhatla

Graduate Theses, Dissertations, and Problem Reports (ETD)

Group III nitride wide band gap semiconductors have recently attracted considerable attention due to their applications for optical devices operating in the blue and UV wavelength regions. Nitride materials are stable at high temperatures and also chemically stable. Analysis of InGaN based blue laser diodes is required for the research and development of future deep UV laser diodes for bio-sensing applications. The conventional multiple quantum wells suffer from inhomogeneous carrier distribution across quantum wells. This inhomogeneous distribution increases the threshold current density of the laser diode. This project addresses the issue through the design of a novel structure for the …

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Dynamic Learning With Neural Networks And Support Vector Machines, Liang Tian Jan 2005

Dynamic Learning With Neural Networks And Support Vector Machines, Liang Tian

Graduate Theses, Dissertations, and Problem Reports (ETD)

Neural network approach has proven to be a universal approximator for nonlinear continuous functions with an arbitrary accuracy. It has been found to be very successful for various learning and prediction tasks. However, supervised learning using neural networks has some limitations because of the black box nature of their solutions, experimental network parameter selection, danger of overfitting, and convergence to local minima instead of global minima. In certain applications, the fixed neural network structures do not address the effect on the performance of prediction as the number of available data increases. Three new approaches are proposed with respect to these …

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Three Essays On The Impacts Of Land -Use Regulations And Land Development, Gi-Don An Jan 2005

Three Essays On The Impacts Of Land -Use Regulations And Land Development, Gi-Don An

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation is a collection of essays examining the effects of land-use regulations and redevelopment. The first chapter describes an overview of the Korean housing market.;Chapter 2 employs the stock-flow model in order to incorporate land-use regulation into the analysis. Future land supply can not only constrain housing construction but also affect the people's expectation. Land-use regulations can be incorporated into demand for housing as well as housing construction.;Chapter 3 investigates the impact of land-use regulations on housing market in the case of South Korea. The South Korean rapid income and population growth have produced a sharp increase in housing …

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Heating Ventilation And Air Conditioning Systems Condition Assessment Methodology, Anand Chandrashekaran Jan 2005

Heating Ventilation And Air Conditioning Systems Condition Assessment Methodology, Anand Chandrashekaran

Graduate Theses, Dissertations, and Problem Reports (ETD)

Facilities (equipment) renewal is assigned low priority due to insufficient budgets in universities, colleges, hospitals, and industries. Insufficient funds lead to postponement of major repairs and replacements of facilities. This lack of investments combined with deterioration of facilities increases the maintenance problem. When funds become available, replacement and repair maintenance projects are carried out, at the cost of the critical ones, due to lack of information on facilities conditions and deficiencies. Thereby developing a facilities condition assessment methodology with a prioritization technique will help in utilizing the available resources effectively. This assessment identifies the physical condition and maintenance deficiencies of …

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Effects Of Heating, Breathing, Hair Style, Posture, And Air Velocity On Breathing Zone Concentrations For An Anthropometrically-Correct Manikin In A Wind Tunnel, Waleed Mahmoud Elnahas Jan 2005

Effects Of Heating, Breathing, Hair Style, Posture, And Air Velocity On Breathing Zone Concentrations For An Anthropometrically-Correct Manikin In A Wind Tunnel, Waleed Mahmoud Elnahas

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ethanol concentrations were measured on an anthropometrically correct, heated, breathing manikin holding a source in its hands at waist height while both sitting and standing in a wind tunnel. The manikin was oriented with its back to the cross draft velocity. Sampling probes were placed at the manikin's mouth, nose, forehead, neck, both collars, center chest and both lapels. Samples were taken from each probe concurrently for 15 minutes by drawing air at 0.15 L/min into separate Teflon(TM) bags using separate sampling lines. The work was divided into two studies each having factorial study designs and two replications of each …

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Development Of A Transparent Indenter Measurement System And Indentation Analysis For Material Mechanical Property Evaluation, Chuanyu Feng Jan 2005

Development Of A Transparent Indenter Measurement System And Indentation Analysis For Material Mechanical Property Evaluation, Chuanyu Feng

Graduate Theses, Dissertations, and Problem Reports (ETD)

Since Tabor showed the application of the spherical indentation approach to obtain material post-yielding true stress-strain curves, the indentation technique has been investigated to determine mechanical properties besides hardness measurement. With the development of various thin film materials, depth-sensing indentation is often applied to evaluate mechanical properties of thin film materials. However, indentation testing is a complicated mechanical process and analytical solutions are difficult to obtain. As a result, much of the understanding of the indentation process has been acquired through experiments and finite element simulations. Thus accurate measurement of indentation parameters is critical in the determination of surface mechanical …

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Energy-Sensitive Machining Parameter Optimization Model, Deepak Prakash Gupta Jan 2005

Energy-Sensitive Machining Parameter Optimization Model, Deepak Prakash Gupta

Graduate Theses, Dissertations, and Problem Reports (ETD)

Manufacturing industries are one of the most important elements in the economic growth and stability of any country. It is very important that the process parameters are given proper attention to maximize the value addition and increased profits for these industries. Parameter optimization for different manufacturing processes has been a challenging and interesting problem in the past. Many researchers have studied the problem of optimizing the process parameters for the turning process. In all the cases studied so far, no one has considered the significance of energy required and its cost for the machining process as an integral part of …

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Numerical Analysis Of Seepage In Earth Slopes, Kishan Kakarla Jan 2005

Numerical Analysis Of Seepage In Earth Slopes, Kishan Kakarla

Graduate Theses, Dissertations, and Problem Reports (ETD)

Seepage is one of the most prominent factors in causing slope stability problems. Installation of longitudinal drainage trenches along the face of the slope can be an alternative solution to reduce the seepage.;The objective of this study was to investigate the effectiveness of the longitudinal drains in reducing the seepage, by using MODFLOW, a three dimensional finite difference groundwater flow model. The influence of various parameters on the performance of longitudinal drains was investigated. These parameters include the trench spacing (w), seepage depth (h), slope angle (theta), length of slope (L) and soil type (K). Numerical analysis was performed for …

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Tabu Search Heuristics For The Dynamic Facility Layout Problem, Wen-Hsing Liu Jan 2005

Tabu Search Heuristics For The Dynamic Facility Layout Problem, Wen-Hsing Liu

Graduate Theses, Dissertations, and Problem Reports (ETD)

The facility layout dramatically influences the efficiency of material handling within a manufacturing system. In order to ensure optimal performance within a manufacturing system, the facility layout should reflect changes throughout time. However, the static facility layout problem with constant material flows between departments may not be a realistic scenario because a manufacturing facility is a dynamic system that constantly evolves. In other words, product demand constantly changes over time. As a result, the dynamic facility layout problem (DFLP) considers these changes and is defined as the problem of assigning departments to locations during a multi-period planning horizon such that …

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Modeling Operational Forestry Problems In Central Appalachian Hardwood Forests, Yaoxiang Li Jan 2005

Modeling Operational Forestry Problems In Central Appalachian Hardwood Forests, Yaoxiang Li

Graduate Theses, Dissertations, and Problem Reports (ETD)

Because of the species diversity, varied site conditions and growth rates, it is really challenging to manage the central Appalachian hardwoods. Examining the harvesting techniques and interactions among stand, harvest, and machines is becoming a concern to the researchers in the region. A simulation system was developed to aid these efforts by estimating the productivity, cost, and traffic intensity of different harvesting configurations under a variety of harvesting prescriptions and stand conditions.;Stands used in the simulation were generated by using the stand generator that was validated by comparing the generated stands with the actual mapped stands statistically. Results indicated its …

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Validating A Neural Network-Based Online Adaptive System, Yan Liu Jan 2005

Validating A Neural Network-Based Online Adaptive System, Yan Liu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Neural networks are popular models used for online adaptation to accommodate system faults and recuperate against environmental changes in real-time automation and control applications. However, the adaptivity limits the applicability of conventional verification and validation (V&V) techniques to such systems. We investigated the V&V of neural network-based online adaptive systems and developed a novel validation approach consisting of two important methods. (1) An independent novelty detector at the system input layer detects failure conditions and tracks abnormal events/data that may cause unstable learning behavior. (2) At the system output layer, we perform a validity check on the network predictions to …

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Arithmetic And Algebra Word Problems: Preservice Teachers' Content Knowledge, Attitudes, And Appreciation Of Students' Strategies, Marc D. Michael Jan 2005

Arithmetic And Algebra Word Problems: Preservice Teachers' Content Knowledge, Attitudes, And Appreciation Of Students' Strategies, Marc D. Michael

Graduate Theses, Dissertations, and Problem Reports (ETD)

The arithmetic and algebraic word problem-solving skills, strategy preferences, and attitudes of preservice elementary and secondary teachers were investigated using a mixed methodology. Teachers' appreciations of student solutions were also examined. Prospective elementary teachers demonstrated flexible problem-solving behaviors while their secondary counterparts tended to prefer algebraic strategies exclusively. In general, the prospective teachers did not demonstrate a greater appreciation for those types of strategies that were typical to their level of training. When communicating the characteristics of an effective strategy, preservice teachers were concerned with organization and clarity rather than the mathematical relevance or appropriateness of the strategy itself. The …

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Fatigue Life Prediction Of Gfrp Composite Material At Coupon And Component Level, Praveenkumar Munagala Jan 2005

Fatigue Life Prediction Of Gfrp Composite Material At Coupon And Component Level, Praveenkumar Munagala

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study unidirectional, bidirectional glass fabric reinforced polymer (GFRP) composites were tested under fatigue loads to determine their fatigue life. The experimental fatigue life of FRP coupons was compared with the predicted fatigue life which was evaluated based on the internal strain energy model proposed by GangaRao and Natarajan (2003). It was found from the strain energy model that the power law accurately describes the relationship between energy release rate, DeltaU and normalized strain, x (applied strain to ultimate strain) as DeltaU = ax b, where 'a' and 'b' are the fatigue coefficients.;Further rectangular single cell and multi-cell GFRP …

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Adaptive Edge-Based Prediction For Lossless Image Compression, Rahul G. Parthe Jan 2005

Adaptive Edge-Based Prediction For Lossless Image Compression, Rahul G. Parthe

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many lossless image compression methods have been suggested with established results hard to surpass. However there are some aspects that can be considered to improve the performance further. This research focuses on two-phase prediction-encoding method, separately studying each and suggesting new techniques.;In the prediction module, proposed Edge-Based-Predictor (EBP) and Least-Squares-Edge-Based-Predictor (LS-EBP) emphasizes on image edges and make predictions accordingly. EBP is a gradient based nonlinear adaptive predictor. EBP switches between prediction-rules based on few threshold parameters automatically determined by a pre-analysis procedure, which makes a first pass. The LS-EBP also uses these parameters, but optimizes the prediction for each pre-analysis …

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Multi-Layer Feed Forward Neural Networks For Foreign Exchange Time Series Forecasting, Bina R. Setyawati Jan 2005

Multi-Layer Feed Forward Neural Networks For Foreign Exchange Time Series Forecasting, Bina R. Setyawati

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation examines the forecasting performance of multi-layer feed forward neural networks in modeling five weekly foreign exchange rates: Australian Dollars/U.S. Dollars (AUS/USD), Euro/U.S. Dollar (EUR/USD), Swiss Franc/U.S. Dollar (CHF/USD), British Pound sterling/U.S. Dollars (GBP/USD), and Japanese Yen/U.S. Dollars (JPY/USD). There are five objectives to accomplish. The first is to determine the key modeling factors that should be considered in topology determination. The second is to compare the performances of Genetic Algorithm (GA) and Modified Tabu Search (TS) in choosing the topology for Neural Networks (NN) implementation. The third is to investigate the suitable learning algorithm for NNs for time …

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Generic Multimodal Biometric Fusion, Yash Shah Jan 2005

Generic Multimodal Biometric Fusion, Yash Shah

Graduate Theses, Dissertations, and Problem Reports (ETD)

Biometric systems utilize physiological or behavioral traits to automatically identify individuals. A unimodal biometric system utilizes only one source of biometric information and suffers from a variety of problems such as noisy data, intra-class variations, restricted degrees of freedom, non-universality, spoof attacks and unacceptable error rates. Multimodal biometrics refers to a system which utilizes multiple biometric information sources and can overcome some of the limitation of unimodal system. Biometric information can be combined at 4 different levels: (i) Raw data level; (ii) Feature level; (iii) Match-score level; and (iv) Decision level. Match score fusion and decision fusion have received significant …

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Detecting Malingered Posttraumatic Stress Disorder Using The Morel Emotional Numbing Test-Revised (Ment-R) And The Miller Forensic Assessment Of Symptoms Test (M-Fast), Julia M. Strunk Jan 2005

Detecting Malingered Posttraumatic Stress Disorder Using The Morel Emotional Numbing Test-Revised (Ment-R) And The Miller Forensic Assessment Of Symptoms Test (M-Fast), Julia M. Strunk

Graduate Theses, Dissertations, and Problem Reports (ETD)

From feigning psychosis to avoid prosecution to claiming an anxiety disorder to receive disability insurance, people from all socioeconomic and educational backgrounds have been suspected of or found to be malingering (Rogers, 1997). The present study investigated the utility of two assessment measures in detecting malingered PTSD: the Morel Emotional Numbing Test-Revised (MENT-R) and Miller Forensic Assessment of Symptoms Test (M-FAST). The Detailed Assessment of Posttraumatic Stress (DAPS) was used as the criterion variable for the following groups: clinical PTSD, subclinical PTSD, honest responders, and coached malingerers. Total scores on the MENT-R distinguished among the four groups of participants. The …

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Circuit Analysis Tools For Evaluating Separation Efficiency Of Dense Medium Separators, Hongyan Sun Jan 2005

Circuit Analysis Tools For Evaluating Separation Efficiency Of Dense Medium Separators, Hongyan Sun

Graduate Theses, Dissertations, and Problem Reports (ETD)

In order to evaluate the relative separation efficiency among various circuits, a modified circuit analysis tools has been developed and applied to some circuits based upon dense medium separation. The results indicated that this circuit analysis method could predict separation efficiency of different circuit configuration without using washability data.;Based on the selective function for one stage separation, the selective functions for multi-stage circuit configurations were derived, and used to simulate the various circuit configurations. The simulation results demonstrated that some circuit configurations can improve the separation efficiency.;In-plant data for two-stage dense medium cylindrical and conical cyclone circuits without recirculation were …

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Integrated Stability Mapping System For Mines, Quanxi Wang Jan 2005

Integrated Stability Mapping System For Mines, Quanxi Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Integrated Stability Mapping System (ISMS) was developed as an engineering tool to quantify the geologic and geo-mechanical information of mines, and to integrate the critical stability influence factors into an overall stability index for use in mine planning and support design. It is generally understood that the inherent underground roof stability is determined by the interaction of both the given geologic characteristics and the local stress influences. Form this perspective, in this dissertation, the need for an integrated stability mapping system is established through investigating the traditional and current hazard mapping practices. In order to fulfill this need, computer …

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A Study Of Assessment Policies And Practices Of Directors In Pre-Kindergarten Programs In West Virginia., Janet Dozier Jan 2005

A Study Of Assessment Policies And Practices Of Directors In Pre-Kindergarten Programs In West Virginia., Janet Dozier

Graduate Theses, Dissertations, and Problem Reports (ETD)

As education for young children becomes more standards-based there has been a cry for more assessments. Developmentally appropriate assessment for young children has been defined by the twelve guidelines developed by the National Association for Young Children. The purpose of this study was done by surveying the 440 pre-kindergarten program directors in West Virginia regarding his/her perception of importance and implementation of those national assessment guidelines and followed by ten structured interviews of directors across the program descriptions. The study found the implementations of guidelines to be positively correlated to the director's perception of importance. Further it found that all …

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The Addiction Severity Index As A Predictor Of Outcome For Inpatients With A Dual-Diagnosis., Larry Spencer Glenn Jan 2005

The Addiction Severity Index As A Predictor Of Outcome For Inpatients With A Dual-Diagnosis., Larry Spencer Glenn

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Addiction Severity Index is the most widely used intake instrument for substance abuse treatment. The National Comorbidity Study (Kessler et al. 1994) indicated that 13.7% of the United States population suffers from a concurrent substance use and mental health disorder within a lifetime. This study explored the utility of the Addiction Severity Index (ASI) and demographic factors as predictors of treatment as rated by staff at discharge. The records of 146 individuals with substance use and mental health diagnoses admitted to a freestanding residential treatment center in Northwestern Pennsylvania were examined to access the predictive properties of the ASI …

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Lift Every Voice: African American Students' Beliefs Of Their School Climate., Constinia Charbonnette Jan 2005

Lift Every Voice: African American Students' Beliefs Of Their School Climate., Constinia Charbonnette

Graduate Theses, Dissertations, and Problem Reports (ETD)

The general purposes of this study were three-fold. The first purpose was to gain an in-depth understanding of West Virginia African American students’ beliefs of their overall school climate. The second purpose of this study was to examine African American students’ beliefs of factors that may positively and negatively affect their academic achievement. Last, the third purpose was to examine participants’ beliefs of high and low achieving African American students. A purposeful sample of 151 secondary students (grades 9-12); in eight West Virginia counties were surveyed and interviewed, using the Generalized Belief Measurement instrument and focus group interviews. Findings from …

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A Study On The Impact Of Visual Stimuli On Initial Saccades., Sruti Ramnath Jan 2005

A Study On The Impact Of Visual Stimuli On Initial Saccades., Sruti Ramnath

Graduate Theses, Dissertations, and Problem Reports (ETD)

The ballistic movement of the human eye to comprehend a scene is known as saccades. Saccadic eye movements have been studied by researchers to understand their role in visual cognition. These eye movements are key to providing the brain with visual information that aids in the interpretation and perception of the scene being viewed. Though saccades are primarily task driven, it has been theorized that the first few saccades are triggered by low-level image properties that are inherent in a scene. Determining and evaluating these properties would enhance the understanding of visual cognition and, thus, benefit the development of “eye-friendly” …

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Application Of Radio Imaging Method (Rim-Iv) In Detecting Geological Anomalies: Two Case Studies., Hua Zhao Jan 2005

Application Of Radio Imaging Method (Rim-Iv) In Detecting Geological Anomalies: Two Case Studies., Hua Zhao

Graduate Theses, Dissertations, and Problem Reports (ETD)

RIM-IV technology is the most promising geophysical method to identify and locate geological anomalies in advance of mining. In order to make this technology successful, ground-truth works are needed to explore its potentials and limitations in application. Two cases in which the RIM-IV technology has been applied to detecting various geological anomalies have been presented in this research. In the first case, the RIM-IV survey was conducted in a section of the longwall panel where sandstone intrusions, seam thinning and severe seam undulations were expected. In the second case, the RIM-IV survey was performed in a section of the longwall …

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The Impact Of Error Propagation On Software Reliability Analysis Of Component-Based Systems., Petar Popic Jan 2005

The Impact Of Error Propagation On Software Reliability Analysis Of Component-Based Systems., Petar Popic

Graduate Theses, Dissertations, and Problem Reports (ETD)

Component based development is gaining popularity in the software engineering community. The reliability of components affects the reliability of the system. Different models and theories have been developed to estimate system reliability given the information about system architecture and the quality of the components. Almost always in these models, one of the key attributes of component-based systems, the error propagation between the components, is overlooked or not taken into account in reliability calculation. This thesis extends previous work on the Bayesian approach to reliability estimation and assessment of component-based systems by introducing the Error Propagation Probability into the model. The …

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