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A Decision Making Model For Evaluating Suppliers By Multi-Layer Feed Forward Neural Networks., Davood Golmohammadi
A Decision Making Model For Evaluating Suppliers By Multi-Layer Feed Forward Neural Networks., Davood Golmohammadi
Graduate Theses, Dissertations, and Problem Reports (ETD)
An efficient decision making model was developed to select suppliers using Multi-Layer Feed Forward Neural Networks. Both types of criteria: qualitative and quantitative, were considered in the model. Fuzzy techniques were applied to convert qualitative data to quantitative data. The model structure was designed and tested. The results of the neural network model indicated that the proper structure of the model had a crucial effect on its performance. The selection of appropriate initial weights, learning rate and momentum were critical in improving the model performance. The applied genetic algorithm showed better performance in comparison with backpropagation. The genetic algorithm was …
The Dynamic Integration Of Distributed Gis Through Semantic Web Services., Xuan Shi
The Dynamic Integration Of Distributed Gis Through Semantic Web Services., Xuan Shi
Graduate Theses, Dissertations, and Problem Reports (ETD)
While interest in the GIS community has traditionally “been almost entirely on the sharing of data†(Goodchild, 2003), Web Service, a solution of software interoperability, is regarded as the “future of geoprocessing†(Hecht, 2002). While data interoperability and data semantics has long been examined in the community of Geographic Information Systems (GIS), exploring the way for the effective sharing of GIS methods and tools is a completely new effort, although such a theme was only talked. Enabling the dynamic integration of geospatial data and geoprocessing functions and resources over heterogeneous systems and platforms through the cutting-edge technology of semantic Web …
The Future Of Clinical Laboratory Science: A Delphi Study., Beverly A. Kirby
The Future Of Clinical Laboratory Science: A Delphi Study., Beverly A. Kirby
Graduate Theses, Dissertations, and Problem Reports (ETD)
The critical shortage of clinical laboratory scientists indicates an urgency for planning for the future. A three-round Delphi study explored the future of the clinical laboratory science profession as predicted by a panel of experts. Thirty-two nationally known authorities in the field were invited and 24 agreed to participate as an expert panel. The first round asked the panelists to respond to the statement, “As I consider the next 20 years of clinical laboratory science as a profession, I believe that the following events might occur.†Round One generated more than 200 events which the investigator synthesized into a 147-event …
Predictive Vegetation Models: A Comparison Of Model Combination Approaches., Benjamin F. Gilmer Iv
Predictive Vegetation Models: A Comparison Of Model Combination Approaches., Benjamin F. Gilmer Iv
Graduate Theses, Dissertations, and Problem Reports (ETD)
The distribution of plants and animals in space and time has long been a focus of many biogeographical and ecological studies. The various approaches for modeling species distributions are rooted in the quantification of the species-environment relationship, where bioclimatic variables are used to explain the distribution of species and communities. Predictive modeling of species distribution has become a widespread tool in the areas of conservation biology, climate change research, land-use/land-cover change assessment, and biodiversity estimates. Although many statistical methods are now available, previous model comparison studies have found little difference in prediction accuracy when models were compared using the same …
A Simple And Reliable Method For Gas Well Deliverability Determination., Arman G. Yussefabad
A Simple And Reliable Method For Gas Well Deliverability Determination., Arman G. Yussefabad
Graduate Theses, Dissertations, and Problem Reports (ETD)
Multi-rate tests generally provide accurate values for gas reservoir formation parameters and deliverability equation coefficients. This type of results enables the engineer to make proper decisions on whether remedial work is required and the potential improvement that can be achieved. The multi-rate tests, such as isochronal or modified isochronal tests, are however cumbersome to conduct due to need for achieving stabilization or lengthy shut-in periods. The goal of this study has been to develop a simple and reliable method for gas well deliverability determination based on a single rate build-up or fall-off test. Traditionally, single rate well tests have been …
Data Discretization Simplified: Randomized Binary Search Trees For Data Preprocessing., Donald Joseph Boland Jr.
Data Discretization Simplified: Randomized Binary Search Trees For Data Preprocessing., Donald Joseph Boland Jr.
Graduate Theses, Dissertations, and Problem Reports (ETD)
Data discretization is a commonly used preprocessing method in data mining. Several authors have put forth claims that a particular method they have written performs better than other competing methods in this field. Examining these methods we have found that they rely upon unnecessarily complex data structures and techniques in order to perform their preprocessing. They also typically involve sorting each new record to determine its location in the preceding data. We describe what we consider to be a simple discretization method based upon a randomized binary search tree that provides the sorting routine as one of the properties of …
Technical Director As Problem Solver: West Virginia University Division Of Theatre And Dance's Production Of "A Flea In Her Ear"., James Gray Daniel
Technical Director As Problem Solver: West Virginia University Division Of Theatre And Dance's Production Of "A Flea In Her Ear"., James Gray Daniel
Graduate Theses, Dissertations, and Problem Reports (ETD)
This paper is intended as an account of the history and process of West Virginia University Division of Theatre and Dance’s production of Georges Feydeau’s farce, A Flea in Her Ear, as presented in the Gladys G. Davis Theatre in the fall of 2006. I will look at this through the eyes and concerns of the Technical Director. It contains a synopsis of the play, a history of this production, problems that arose and their solutions and an assessment of how things went. It is supported by notes, technical drawings and photographs.
Analysis Of Cutting Parameters And Heat Generation On Bits Of A Continuous Miner - Using Numerical And Experimental Approach., Brijes Mishra
Analysis Of Cutting Parameters And Heat Generation On Bits Of A Continuous Miner - Using Numerical And Experimental Approach., Brijes Mishra
Graduate Theses, Dissertations, and Problem Reports (ETD)
Analysis of the cutting process of a continuous miner in a coal mine requires a tedious experimental set up. But with the advance of modern computers, such complex system can be simulated using numerical modeling. It is the goal of this dissertation to use finite element analysis to investigate the effect of bit design and drum design on cutting. The study involved the use of a miniature cutting drum and three dimensional finite element models to achieve the goal. The miniature cutting drum named as Automated Rotary Coal Cutting Simulator (ARCCS) was developed to analyze the cutting process. The cutting …
Efficient Routing Of Snow Removal Vehicles, Masoud Omer
Efficient Routing Of Snow Removal Vehicles, Masoud Omer
Graduate Theses, Dissertations, and Problem Reports (ETD)
This research addresses the problem of finding a minimum cost set of routes for vehicles in a road network subject to some constraints. Extensions, such as multiple service requirements, and mixed networks have been considered. Variations of this problem exist in many practical applications such as snow removal, refuse collection, mail delivery, etc. An exact algorithm was developed using integer programming to solve small size problems. Since the problem is NP-hard, a heuristic algorithm needs to be developed. An algorithm was developed based on the Greedy Randomized Adaptive Search Procedure (GRASP) heuristic, in which each replication consists of applying a …
Productivity And Carbon Budgets Of Harvested Central Appalachian Forests, Sarah C. Davis
Productivity And Carbon Budgets Of Harvested Central Appalachian Forests, Sarah C. Davis
Graduate Theses, Dissertations, and Problem Reports (ETD)
Land conversion and industrial pollution are two of the most influential vehicles for anthropogenic perturbation of natural terrestrial processes and both have increased dramatically over the course of the last century. This research explores the role of Central Appalachian hardwood forests in the global carbon (C) balance during a century of regeneration with changing land use and atmospheric pollution. Most of the forests in this region were logged in the early 1900s. During the century the followed, nitrogen (N) deposition rates became especially high in parts of Central Appalachia where an increasing number of regenerated mature forests are now undergoing …
Investigation Of Hole Cleaning Parameters Using Computational Fluid Dynamics In Horizontal And Deviated Wells, Nekkhil Mishra
Investigation Of Hole Cleaning Parameters Using Computational Fluid Dynamics In Horizontal And Deviated Wells, Nekkhil Mishra
Graduate Theses, Dissertations, and Problem Reports (ETD)
The need for technologies to reduce cost and improve recovery from existing hydrocarbon reservoirs is well established. One of the most effective methods of cost reduction relies on improvement of drilling technologies. Particularly, understanding the parameters that control hole cleaning is beneficial especially in both horizontal and deviated wells. For this purpose, a section of casing-drill pipe annulus section was simulated using Computational Fluid Dynamics to determine the effects of fluid velocity, cutting size, rate of penetration, drill pipe rotation and inclination angle in deviated wells. The Eulerian Model Simulations were conducted at steady state and the results of the …
Evaluation Of Heavy Duty Diesel Engines Regulated Emissions Based On Variation Of Fuel Properties By Use Of Additives, Robert Ray Tincher
Evaluation Of Heavy Duty Diesel Engines Regulated Emissions Based On Variation Of Fuel Properties By Use Of Additives, Robert Ray Tincher
Graduate Theses, Dissertations, and Problem Reports (ETD)
Heavy-duty diesel engines exhaust emissions contribute to the ambient air quality; therefore, the United States Environmental Protection Agency (EPA) and California Air Resources Board (CARB) have created stringent emissions standards. Since the implementation of these standards in the early 1970s, overall engine and fuel technology improvement have created a significant reduction in emissions. Many different factors, such as fuel composition, properties, additives, and engine technology, influence regulated emissions constituents.;This study was completed in order to evaluate engine emissions from several different diesel fuels with and without cetane improving additives on recent and early production electronically controlled heavy duty diesel engines …
Automated Ventricular Measurements Using Gabor Wavelets, Hemalatha Sampath
Automated Ventricular Measurements Using Gabor Wavelets, Hemalatha Sampath
Graduate Theses, Dissertations, and Problem Reports (ETD)
Magnetic Resonance Imaging (MRI) is one of the widely used medical technologies for diagnosis of various degenerative diseases like Alzheimer's disease. In degenerative diseases the brain atrophies resulting in enlarged ventricles. The segmentation of the ventricle and the total ventricle volume measurement can be important in the analysis of the neurological disease severity and in studies of animal models of disease used to advance treatments for people. This thesis is focused on using Gabor wavelets for ventricular measurements in a rabbit model of Alzheimer's disease.;Standard intensity-based tools like Statistical Parametric Mapping (SPM) used for human brain segmentation requires a priori …
Propanil (3,4-Dcpa)-Induced Alterations Of Macrophage Function, Irina V. Ustyugova
Propanil (3,4-Dcpa)-Induced Alterations Of Macrophage Function, Irina V. Ustyugova
Graduate Theses, Dissertations, and Problem Reports (ETD)
The pesticide 3,4-dichloropropionanilide (propanil or alternatively, DCPA) is a post-emergent herbicide predominantly used for the control of weeds on commercial rice crops worldwide. The US Environmental Protection Agency report on "Pesticides Industry Sales and Usage in 2001" ranked propanil as the 17th most used herbicide in the US. It is applied on the fields via groundboom sprayers or aerial equipment suppressing photosynthesis and carbon fixation of a growing plant. The primary target of herbicide exposure is personnel working in the manufacturing and application who are required to wear personal protective equipment to minimize the exposure. The common routes of this …
Finite Element Analysis Of Slope Stability, Pinar Wanstreet
Finite Element Analysis Of Slope Stability, Pinar Wanstreet
Graduate Theses, Dissertations, and Problem Reports (ETD)
Slope stability is an important aspect of geotechnical engineering. The use of finite element analysis of slope stability has gained popularity in recent years due to its capability to handle complex problems. The primary focus of this research was to study the influence of soil nailing on the factor of safety of stability of slopes by using finite element analysis, and to investigate failure mechanism. In this paper, stability of various soil slopes was analyzed using the Shear Strength Reduction (SSR) technique. Finite element analysis was performed on both reinforced and unreinforced soil slopes and the results were compared with …
Simulation Of Friction Stir Spot Welding (Fssw) Process: Study Of Friction Phenomena., Mokhtar Awang
Simulation Of Friction Stir Spot Welding (Fssw) Process: Study Of Friction Phenomena., Mokhtar Awang
Graduate Theses, Dissertations, and Problem Reports (ETD)
Recently, friction stir spot welding (FSSW), a variant of “linear” friction stir welding (FSW) has received considerable attention from automobile industries to replace electric resistance spot welding with aluminum frames. Thus far, the FSSW process has been successfully developed and applied in various cases, but the physics behind the process is not yet fully understood. Effective and reliable computational models of the FSSW process would greatly enhance the study of friction phenomena during the process as well as energy dissipation. Approaches for the computational modeling of the FSSW process, however, are still under development and much work is still needed, …
Sensor Validation Scheme With Virtual Nitrogen Oxides Sensing For Heavy Duty Diesel Engines., Victor C. Chew
Sensor Validation Scheme With Virtual Nitrogen Oxides Sensing For Heavy Duty Diesel Engines., Victor C. Chew
Graduate Theses, Dissertations, and Problem Reports (ETD)
On January 24, 2007, Environmental Protection Agency (EPA) signed a proposed regulation to require an On-Board Diagnostics (OBD) system to monitor malfunctions in large highway diesel and gasoline trucks over 14,000 lbs from 2010 onwards. A sensor validation scheme, known as SFDIA which has been used in aircraft controls were modified and developed to not only monitor sensor malfunctions but also isolate the faulty sensor signals. The isolated signals would then be accommodated using an estimated value obtained from predictive sensor models. The models for this study were developed using a statistical modeling technique known as Multivariate Adaptive Regression Splines …
The Generalized Machine Layout Problem., Juan R. Jaramillo
The Generalized Machine Layout Problem., Juan R. Jaramillo
Graduate Theses, Dissertations, and Problem Reports (ETD)
Businesses, including manufacturing companies, must reduce cost to survive in today’s economy. During the last several decades, to reduce cost, many companies began to focus on labor optimization and/or increasing productivity. This may require an increase in investment cost (e.g., equipment costs). Among the consequences of these policies is a significant reduction in direct labor cost. The necessity to reduce direct labor cost has made material handling cost more important than ever. Material handling cost reductions can be obtained by designing efficient layouts. Efficient layouts are obtained by solving machine and facility layout problems effectively. Commonly, facility and machine layout …
George Crumb's "Pastoral Drone": Analysis And Pedagogical Recommendations., Krista A. Shinew
George Crumb's "Pastoral Drone": Analysis And Pedagogical Recommendations., Krista A. Shinew
Graduate Theses, Dissertations, and Problem Reports (ETD)
This study demonstrates that though Pastoral Drone is Crumb's only foray into the solo organ repertoire it still demonstrates the characteristic traits found in his other compositions and should be a vital piece in a graded repertoire. A detailed analysis of the work illustrates that prime numbers, texture, and timbre all contribute to delineating the form of Pastoral Drone. The paper details the pedagogical benefits to including Pastoral Drone in the repertoire of maturing organists. There are also suggestions for modified organ registrations that not only allow for a more successful performance of Pastoral Drone, but also encourage young organists …
Durable Consumption And The Life Cycle Permanent Income Hypothesis: Evidence From Survey Data., Chaiwuth Tangsomchai
Durable Consumption And The Life Cycle Permanent Income Hypothesis: Evidence From Survey Data., Chaiwuth Tangsomchai
Graduate Theses, Dissertations, and Problem Reports (ETD)
This dissertation uses the survey data from the Survey of Consumer Finances (SCF) and the Survey of Income and Program Participation (SIPP) to test the Life Cycle Permanent Income Hypothesis (LCPI) as it applies to the consumption of durable goods. To measure durable consumption services (“durable consumption,†for short) housing and vehicle consumption data are employed. We find that households mostly behave as implied by the LCPI Hypothesis, although they consume from their permanent income somewhat less than what the strict LCPI Hypothesis predicts. We also incorporate the effect of household financial constraints, which have previously been shown to have …
Perception Of Students With Disabilities: An Assessment Of Attitudes Held By Pre-Service Teachers., Suzanne Gosden Kitchen
Perception Of Students With Disabilities: An Assessment Of Attitudes Held By Pre-Service Teachers., Suzanne Gosden Kitchen
Graduate Theses, Dissertations, and Problem Reports (ETD)
This study explored the attitudes pre-service teachers held toward people with disabilities. The researcher conducted a survey methodology study via questionnaire of repeated measures design, using the respondents as their own controls. The goal of this study was to find out if pre-service teachers attitudes toward people with disabilities were affected by descriptive labels such as physicaldisability or mental disability. In other words, did the type of disability affect the pre-service teachers attitudes toward that person? Findings revealed that pre-service teachers had a more negative attitude toward people labeled with mental disabilities, and a more positive attitude toward people labeled …
Coating Uniformity On A Pharmaceutical Tablet: An Experimental Study And Finite Volume Modeling Of Droplet Impact Behavior., Ku Zilati Ku Shaari
Coating Uniformity On A Pharmaceutical Tablet: An Experimental Study And Finite Volume Modeling Of Droplet Impact Behavior., Ku Zilati Ku Shaari
Graduate Theses, Dissertations, and Problem Reports (ETD)
The behavior of a single liquid droplet impacting a solid surface is a complex phenomenon and is a basic component of various industrial processes. One such process is the film coating process in the pharmaceutical industry, where coating uniformity is important especially if the coating is for functional purposes. Coating variability on a tablet could be affected by several factors, one of which is the impingement of droplets on its surface. The spreading behavior of a droplet on a solid surface was reported to be affected by the surface properties, particularly the surface roughness. To understand these phenomena completely, a …
Participatory Gis Approaches To Environmental Impact Assessment: A Case Study Of The Appalachian Corridor H Transportation Project., Ram Alagan
Graduate Theses, Dissertations, and Problem Reports (ETD)
This dissertation explores the strengths and weaknesses of Participatory Geographic Information System (PGIS) approaches to Environmental Impact Assessment (EIA) with a specific focus on the potential contribution of Geo-visualization (GVIS) in this process. The approach draws heavily on concepts developed under the broad umbrella of GIS and Society and Critical GIS. PGIS recognizes the political economy of GIS in terms of data access, data representation, structural knowledge distortion, and community empowerment as being legitimate and significant issues in the application of GIS in community projects. EIA has been adopted as one of several important environmental practices that seek to engage …
An Investigation Of Student Characteristics' Influence On Retention At A Two-Year Proprietary Career College., Lisa Boice
Graduate Theses, Dissertations, and Problem Reports (ETD)
Many students who enroll in higher education fail to complete their credential. This is especially true for students enrolled in two-year proprietary colleges where almost half leave without meeting their educational goals. Students at these institutions are largely underprepared and mostly nontraditional; their attrition has dire consequences for not only their own success, but that of society as well. Because most two-year students who drop out of college do so in their first year, early identification and intervention strategies are critical for student accomplishment and graduation. The purpose of the study was to uncover key retention issues that students face …
Mathematics Vocabulary Instruction For Current Non-Proficient Students With And Without Ieps: A Study Of Three Methods Of Instruction., George D. Brown
Mathematics Vocabulary Instruction For Current Non-Proficient Students With And Without Ieps: A Study Of Three Methods Of Instruction., George D. Brown
Graduate Theses, Dissertations, and Problem Reports (ETD)
The purpose of this experimental study was to determine which of three methods of vocabulary instruction, including the common approach method, a combination of the common approach method and keyword method, and a combination of the common approach method and the keyword/illustration method of instruction was most effective in teaching mathematics vocabulary over the course of two mathematical units. Grade eight students (N=60) from two rural middle schools who scored at the basic level on the 2006 Maryland School Assessment (MSA) in mathematics and reading participated in this experimental study. Students with individualized education plans (n=24) and regular education students …
A Web-Based Tool For Analysis Of Crime Laboratory Data., Ramesh Annabathula
A Web-Based Tool For Analysis Of Crime Laboratory Data., Ramesh Annabathula
Graduate Theses, Dissertations, and Problem Reports (ETD)
The focus of this project was on the development of a software tool for analysis of crime data at the West Virginia State Police Forensics Laboratory (WVSPFL). The tool enables users to conduct statistical analysis on criminal activity; in addition, data mining methods are implemented to identify possible crime patterns. A Crime database was implemented; it contains information on incidents submitted to WVSPFL over the last fifteen years. The WVSPFL database was integrated with a hypothetical conviction database. Such integration enables law enforcement agencies to track crime from occurrences to conviction. It is anticipated that data mining methods will assist …
A Hybrid Approach To Expert And Model Based Effort Estimation., Daniel Ryan Baker
A Hybrid Approach To Expert And Model Based Effort Estimation., Daniel Ryan Baker
Graduate Theses, Dissertations, and Problem Reports (ETD)
It is important to have a good cost estimate in order to budget a new project. Unfortunately, software effort estimation methods are often inaccurate. Molokken and Jorgensen report that 60-80% of the time a software project will overrun its estimate by an average of 30% [98]. Furthermore, most estimates do not describe the uncertainty of the estimate [52,54,118]. In addition, each source of uncertainty, as described by Kitchenham and Linkman [68], has yet to be represented. In this thesis, the design principles of an effort estimation tool called 2CEE are discussed. This tool is currently being deployed at NASA’s Jet …
Correlation Of Electrical And Optical Properties Of Cadmium Germanium Arsenide., Chunchuan Xu
Correlation Of Electrical And Optical Properties Of Cadmium Germanium Arsenide., Chunchuan Xu
Graduate Theses, Dissertations, and Problem Reports (ETD)
As a nonlinear optical material, CdGeAs2 can be used in frequency conversion applications in the infrared. This work is going to explain the details of optical properties by using Hall effect measurements. The temperature dependent Hall effect measurements were conducted on about 100 CdGeAs 2 bulk samples which were grown by the horizontal gradient freeze technique. The Hall data were fitted to extract the electrical parameters acceptor concentration, donor concentration, activation energy and mobility ratio. Correlations between Hall data and both absorption and photoluminescence data were determined. These data consistently support the defect model that has one shallow donor, one …
Essays In Trade, Foreign Aid And Investment. Essay 1: Motivation For Bilateral Aid Allocation: Altruism Or Trade Benefits. Essay 2: Does Institutional Quality Matter For Investment And Capital Mobility? Evidence From Sub -Saharan Africa. Essay 3: Do Donors Care About Declining Trade Revenue From Liberalization? An Analysis Of Aid Allocation. (With Subhayu Bandyopadhyay)., Javed Younas
Graduate Theses, Dissertations, and Problem Reports (ETD)
Essay 1: Motivation for bilateral aid allocation: Altruism or trade benefits. This paper argues that bilateral aid from developed OECD countries is disproportionately allocated to recipient nations who have a greater tendency to import goods in which donor nations have a comparative advantage in production. The estimates indicate that a substantially larger amount of aid per capita is provided to recipients who import capital goods, while imports by other category groups have no significant effects. Given that developed donor nations are major producers and exporters of capital goods, this result at least partially supports their trade benefits motive. On the …
Response And Time Allocation On Concurrent Variable -Interval Schedules Of Signaled And Unsignaled Reinforcement, Jeffrey Everly
Response And Time Allocation On Concurrent Variable -Interval Schedules Of Signaled And Unsignaled Reinforcement, Jeffrey Everly
Graduate Theses, Dissertations, and Problem Reports (ETD)
The present experiments were designed to evaluate accounts of how behavior is allocated on concurrent variable-interval (VI) VI schedules. The generalized matching law assumes that the proportion of behavior allocated to the two schedules will match the proportion of reinforcers obtained on the two schedules (Baum, 1974). An alternate view holds that under ideal conditions, behavior should "fix" almost exclusively at the richer schedule. The leaner schedule is only visited, or "sampled", when a reinforcer becomes available on that schedule (Houston & McNamara, 1981). Attempts were made to create optimal conditions for producing an ideal fix-and-sample response pattern. Pigeons were …