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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Facilitating Sensor Interoperability And Incorporating Quality In Fingerprint Matching Systems, Rohan D. Nadgir Aug 2006

Facilitating Sensor Interoperability And Incorporating Quality In Fingerprint Matching Systems, Rohan D. Nadgir

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis addresses the issues of sensor interoperability and quality in the context of fingerprints and makes a three-fold contribution. The first contribution is a method to facilitate fingerprint sensor interoperability that involves the comparison of fingerprint images originating from multiple sensors. The proposed technique models the relationship between images acquired by two different sensors using a Thin Plate Spline (TPS) function. Such a calibration model is observed to enhance the inter-sensor matching performance on the MSU dataset containing images from optical and capacitive sensors. Experiments indicate that the proposed calibration scheme improves the inter-sensor Genuine Accept Rate (GAR) by …

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Evaluation And Performance Prediction Of Multimodal Biometric Systems, Nevena Samoska Aug 2006

Evaluation And Performance Prediction Of Multimodal Biometric Systems, Nevena Samoska

Graduate Theses, Dissertations, and Problem Reports (ETD)

Multibiometric systems fuse the evidence presented by different biometric sources in order to improve the matching accuracy of a biometric system. In such systems, information fusion can be performed at different levels; however, integration at the matching score level is the most commonly used approach due to the tradeoff between information content and accessibility. This work develops a tool in order to analyze the impact of various normalization schemes on the matching performance of score-level fusion algorithms. The tool permits the systematic evaluation of different fusion rules after employing normalizing and mapping the match scores of different modalities into a …

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Evaluation Of Sterling Silver As A Contacting Material For The Cathode Chamber Of The Solid-Oxide Fuel Cell, John Sakacsi Aug 2006

Evaluation Of Sterling Silver As A Contacting Material For The Cathode Chamber Of The Solid-Oxide Fuel Cell, John Sakacsi

Graduate Theses, Dissertations, and Problem Reports (ETD)

In recent years the operating temperature of the SOFC has been reduced to ~800C, making it possible to use silver in the fabrication of the cell stack. Silver is attractive due to its high conductivity, ductility and the fact that it does not form non-conductive scales that could reduce the performance of the fuel cell stack. This research focuses on the development and testing of candidate materials, utilizing silver, in a simulated cathode environment using a simple tube furnace and air supply. Test specimens were fabricated using simple powder metallurgy techniques or by the oxidation of specific alloys to create …

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Composite Suspension Member Analysis, Bruce M. Schlicker Aug 2006

Composite Suspension Member Analysis, Bruce M. Schlicker

Graduate Theses, Dissertations, and Problem Reports (ETD)

As research has developed advancement in composites, they are increasingly being used as components in dynamic situations, e.g. suspension members. Previously used alloy materials are being replaced. Current research has led to developments in attaching aluminum to the composite. This new material is often referred to as a hybrid composite.;Hybrid composites used as suspension components become popular for their increased design flexibility. In this thesis, the shock mounting point was of the concern. It was found that the weak link in the hybrid aluminum/composite attachment is the bond between the aluminum and the epoxy.;Experiments and research led to advancements and …

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Machine Vision Applications In Uavs For Autonomous Aerial Refueling And Runway Detection, Larry W. Rowe Ii Aug 2006

Machine Vision Applications In Uavs For Autonomous Aerial Refueling And Runway Detection, Larry W. Rowe Ii

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research focuses on the application of Machine Vision (MV) techniques and algorithms to the problems of Autonomous Aerial Refueling (AAR) and Runway Detection. In particular, real laboratory based hardware was used in a simulated environment to emulate real-life conditions for AAR. It was shown that the K-Means Clustering Algorithm solution to the Marker Detection problem could be executed at a frame rate of 30 Hz and it averaged a tracking error of less than one pixel while utilizing only 0.16% of the image. It was also shown that the solution to the Runway Detection problem could be executed at …

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Analysis Of Energy Consumption In Continuous Galvanizing Lines, Raviraj Ratnakar Chavan Aug 2006

Analysis Of Energy Consumption In Continuous Galvanizing Lines, Raviraj Ratnakar Chavan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The pot hardware in continuous galvanizing lines is prone to failure and needs to be replaced quite frequently. This resulted in considerable loss of production time. Also equipment like, the molten zinc pot and annealing furnace cannot be turned off during downtime resulting in considerable energy consumption during downtime too.;A profound study of the energy aspect of the equipment used on galvanizing line was done. A systematic approach was used to collect and analyze the data from galvanizing facilities. A decision support system (DSS) that will take into account all the major energy consuming equipment in a typical hot dip …

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Cycles And Weight Effects On Emissions And Development Of Predictive Emissions Models For Heavy Duty Trucks, Kuntal A. Vora Aug 2006

Cycles And Weight Effects On Emissions And Development Of Predictive Emissions Models For Heavy Duty Trucks, Kuntal A. Vora

Graduate Theses, Dissertations, and Problem Reports (ETD)

NOX and PM emissions data from the 5--mode CARB HHDDT Schedule, UDDS, and AC5080 were reviewed, with reference to each other. Next, two-dimensional correlations were used to predict the emissions rate on one cycle from the rates of two other cycles. The two-dimensional analysis yielded better correlations.;The emission of NOX, CO, CO2, HC and PM were analyzed with respect to weight. Vehicles did not follow linear NOX emissions trends over large weight ranges. Fleet-wide emissions for HHDDT could be predicted.;Lastly, a method was proposed to predict emissions based on the vehicle's emissions history from other cycles and on the properties …

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Optical-Based Atr Algorithms For Applications In Swarmed Uavs, Vasavi Rangammagari Aug 2006

Optical-Based Atr Algorithms For Applications In Swarmed Uavs, Vasavi Rangammagari

Graduate Theses, Dissertations, and Problem Reports (ETD)

Swarmed Unmanned Aerial Vehicles (UAVs) with Automatic Target Recognition (ATR) technology are becoming an important element of electronic warfare. The advantages of UAVs over piloted vehicles have increased the need to develop robust and reliable ATR algorithms. Various issues like changing weather, camouflage, low contrast and resolution, clutter, inadequate databases place a limit on the performance capabilities of a typical ATR algorithm. In an effort to deal with these issues, a correlation-based algorithm is proposed in this thesis. This algorithm calculates the correlation between the input image and a target template which is created by projecting a 3-D model from …

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Web-Based Forensic Information Management System, Parmjit Singh Aug 2006

Web-Based Forensic Information Management System, Parmjit Singh

Graduate Theses, Dissertations, and Problem Reports (ETD)

The focus of this work was on the design and implementation of a web based forensic information management system for the West Virginia State Police Forensics Laboratory (WVSPFL). The software tool enables law enforcement agents to submit crime information to the Forensic Laboratory via a secure Internet connection. The tool also enables each of the nine units of WVSPFL to process the information electronically. Online electronic forms were created to mirror the existing paper based forms, making the transition easier. The existing processes were standardized and streamlined, there by minimizing information inconsistency. The crime information once gathered is automatically uploaded …

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Benefits To Signal Timing Optimization And Its To Corridor Operations, Darian Glitz May 2006

Benefits To Signal Timing Optimization And Its To Corridor Operations, Darian Glitz

Graduate Theses, Dissertations, and Problem Reports (ETD)

Traffic signals are one of the primary constraints on corridor capacity in the highway/arterial network. The amount traffic is impeded is heavily dependent on the quality of the signal timings.;The purpose of this research was to conduct a case study of a congested corridor to demonstrate the benefits of traffic signal retiming/optimization on corridor operations. Tactically, this research involved development and application of a methodology to develop and assess signal timing plan alternatives. The research demonstrated the benefits in terms of delay, travel time, emissions, and fuel consumption. Strategically, this project can be used to provide a concrete example of …

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Effects Of Morrow's Honeysuckle Control And The Impact Of The Shrub On Invertebrates At Fort Necessity National Battlefield, Pennsylvania, Jason Patrick Love May 2006

Effects Of Morrow's Honeysuckle Control And The Impact Of The Shrub On Invertebrates At Fort Necessity National Battlefield, Pennsylvania, Jason Patrick Love

Graduate Theses, Dissertations, and Problem Reports (ETD)

Lonicera morrowii (Morrow's honeysuckle) dominates a degraded meadow at Fort Necessity National Battlefield, Pennsylvania, U.S.A. We tested four removal methods of Morrow's honeysuckle during spring and autumn 2004. Cut, stump application of 20% glyphosate, and mechanical removal in autumn were not successful (<47% reduction), while mechanical removal in spring and foliar application of 2% glyphosate were somewhat successful (>66% reduction). We used a modified leaf blower to sample invertebrates at our site. Invertebrate biomass was lowest within the native shrub, Viburnum recognitum (southern arrowwood) (p<0.05). Biomass of larval leaf chewers was highest in the native shrub. Invertebrate abundance, biomass, and richness were reduced under dense thickets of Morrow's honeysuckle (p<0.05), due to low amount of herbaceous cover beneath the shrubs. The amount of leaf area consumed by herbivores was 10 times more on the native shrub. Overall, our findings reveal that the exotic shrubs negatively impact invertebrate communities.

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Ignition By Air Injection (Cibai) For Controlled Auto-Ignition In A Cfr Engine, Fernando Echavarria May 2006

Ignition By Air Injection (Cibai) For Controlled Auto-Ignition In A Cfr Engine, Fernando Echavarria

Graduate Theses, Dissertations, and Problem Reports (ETD)

Compression ignition by air injection (CIBAI) has been successfully achieved in a modified single cylinder, four-stroke, spark ignition cooperative fuel research (CFR) engine. The CIBAI cycle was invented by Professor John Loth and Professor Gary Morris, US patent No's: 6,994,057 Feb. 7, 2006 and 6,899,061 May 31, 2005. This new revolutionary combustion concept has the potential to become an alternative to traditional (SI) spark ignited and compression ignited (CI) diesel engines.;The objective of this dissertation was to demonstrate experimentally the viability of achieving ignition by air injection (CIBAI) for controlled auto-ignition in a CFR engine. This experimental work involved the …

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The Impact Of Reservoir Properties On Mixing Of Inert Cushion And Natural Gas In Storage Reservoirs, Balaji S. Srinivasan May 2006

The Impact Of Reservoir Properties On Mixing Of Inert Cushion And Natural Gas In Storage Reservoirs, Balaji S. Srinivasan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Underground natural gas storage is a process which effectively balances a variable demand market with a nearly constant supply of energy provided by the pipeline system. Cushion gas in storage reservoirs provide the necessary pressure for the withdrawal of working gas and it makes up for the largest part of investments in underground storage reservoirs. Usually, a part of the cushion gas is replaced by an inert gas such as Nitrogen in order to reduce the investment costs. Due to this replacement there might be problems caused by the mixing of inert cushion and natural gas, which is a cause …

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Updating Low-Profile Frp Deck Fe Model Using Experimental Modal Analysis, Srinivas Aluri May 2006

Updating Low-Profile Frp Deck Fe Model Using Experimental Modal Analysis, Srinivas Aluri

Graduate Theses, Dissertations, and Problem Reports (ETD)

A FRP composite cargo trailer was developed for the U.S. Marine Corps using the existing Prodeck4 FRP bridge deck as a trailer bed. Detailed finite element analysis and experimental evaluation was carried out on the FRP trailer. The FRP deck used is a new system and has orthotropic material properties, therefore an FE model of deck that is validated through experimental data will ensure confidence in results obtained from the FE model. Experimental modal analysis (EMA) was used to verify and update the FE model of the FRP deck.;A FE model of FRP deck was built in ANSYSRTM and the …

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Thermal Conductivity Characterization Of Composite Materials, Bhyrav Mutnuri May 2006

Thermal Conductivity Characterization Of Composite Materials, Bhyrav Mutnuri

Graduate Theses, Dissertations, and Problem Reports (ETD)

Thermal conductivity of a polymer composite is a function of resin type, fiber type and architecture, fiber volume fraction, direction of heat flow, and service temperature. Recognizing the thermal responses in Fiber Reinforced Polymer (FRP) composite decks play a critical role in their performance, accurate thermal measurements of FRP decks are essential.;The objective of the research is to attain better understanding of global and local thermal behavior of a composite structural system through fundamental understanding of thermal conductivity properties. The literature reveals that a major focus has been placed on measurements of thermal conductivity in through-the-thickness direction of a FRP …

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Development Of Gas Production Type Curves For Horizontal Wells In Coalbed Methane Reservoirs, Allen Ekahnzok Nfonsam May 2006

Development Of Gas Production Type Curves For Horizontal Wells In Coalbed Methane Reservoirs, Allen Ekahnzok Nfonsam

Graduate Theses, Dissertations, and Problem Reports (ETD)

Coalbed methane is an unconventional gas resource that consists of methane production from coal seams. The unique difference between CBM and conventional gas reservoirs is that it is a dual-porosity system characterized by complex interaction of the coal matrix and cleat system that are coupled through the desorption process. Coalbed methane reservoir performance is controlled by a complex set of reservoir, geologic, completion and operation parameters. To date there are very little tools to help with predicting the performance of CBM wells.;The purpose of this research was to develop a simple and reliable tool to help with gas production predictions …

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Projection Of Truck Traffic Volumes At Interstate Permanent Automatic Traffic Recorders, Alex M. Sanchez May 2006

Projection Of Truck Traffic Volumes At Interstate Permanent Automatic Traffic Recorders, Alex M. Sanchez

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study documents the development of a methodology and models to forecast truck traffic volumes on Interstate Highways at a selection of Permanent Automatic Traffic Recorder (PATR) sites. The models were developed using data collected over a period nine years (1995 to 2003) from sixteen permanent count stations located throughout the state. Eight sites were ultimately utilized, five along rural interstate highways and the others from urban interstate highways. Model development was based on the time series method, using two techniques: regression analysis and the growth factor technique. Both were analyzed and compared in order to select the most reliable …

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Willingness To Pay As A Predictor Of Viability For Three Different Recreational Pass Variables, Jessica Ann Neff May 2006

Willingness To Pay As A Predictor Of Viability For Three Different Recreational Pass Variables, Jessica Ann Neff

Graduate Theses, Dissertations, and Problem Reports (ETD)

In 1996, under the Clinton administration, the recreation fee demonstration program (RFDP) was authorized by Congress as a three-year pilot program. The initial authorization of the fee program was extended numerous times until it was proposed to become a permanent part of the legislation. In December 2004, Congress passed the Federal Lands Recreation Enhancement Act (FREA) (P.L. 108-447), which permanently authorized the five federal land agencies to continue a recreation fee program for a period of ten years. The purpose behind FREA is to retain recreation fee revenues to supplement appropriations and other funding sources. Recreation fee dollars differ from …

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Learning And Developing Professional Behaviors As Part Of An Entry-Level Physical Therapy Education: A Survey Of Students And Practicing Clinicians, D. Scott Davis May 2006

Learning And Developing Professional Behaviors As Part Of An Entry-Level Physical Therapy Education: A Survey Of Students And Practicing Clinicians, D. Scott Davis

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this dissertation was to examine the state of professionalism in the physical therapy profession. The literature suggests that professionalism is a concern in many professions including medicine, law, nursing, audiology, and physical therapy. Two separate but parallel surveys were used to identify the opinions and experiences of physical therapy students and licensed physical therapists. The student survey consisted of a four-page paper and pencil survey that was mailed to 20 randomly selected CAPTE accredited physical therapy programs. Of the 1,525 available students, 336 (22%) physical therapy students participated in the investigation. The clinician survey consisted of a …

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An Evaluation Of Vibration And Other Effects On The Accuracy Of Grip And Push Force Recall, Thomas W. Mcdowell May 2006

An Evaluation Of Vibration And Other Effects On The Accuracy Of Grip And Push Force Recall, Thomas W. Mcdowell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Operators of vibratory hand tools can be at risk of developing health problems associated with repeated forceful actions and exposure to intense hand-transmitted vibration. To better assess health risks, comprehensive risk evaluations of these tasks must include quantitative assessments of hand-tool coupling forces. Researchers have used instrumentation for such measurements; but those techniques may be ill-suited for certain field environments. Psychophysical force-recall techniques have been proposed as alternatives to handle instrumentation. This study comprised two experiments that examined the effects of vibration and other factors upon force-recall accuracy and reliability. In each experiment, participants applied specific grip and push forces …

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A Delphi Study To Identify Teaching Competencies Of Teacher Education Faculty In 2015, Sonhwa Na May 2006

A Delphi Study To Identify Teaching Competencies Of Teacher Education Faculty In 2015, Sonhwa Na

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to reach consensus on future course delivery modes and recommended teaching competencies that would be required for teacher education faculty in future course delivery environments. A three-round, online modified Delphi study was used to answer the following research questions (RQs): (a) RQ1: What course delivery modes will teacher education faculty of traditional colleges and universities be using in 2015?, and (b) RQ2: What competencies will teacher education faculty of traditional colleges and universities need to teach using these delivery modes? Course delivery modes and general teaching competencies were determined as a result of consensus …

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A Study Of The Concept Of Interactivity As It Applies To Online Newspapers, Bradley Thomas Pedersen May 2006

A Study Of The Concept Of Interactivity As It Applies To Online Newspapers, Bradley Thomas Pedersen

Graduate Theses, Dissertations, and Problem Reports (ETD)

This project examines how frequently a sampling of online newspapers incorporates interactive features into online content. The newspapers for the study represent the eastern, western and central regions of the United States. The analysis focused on the amount of links and their destination, opportunities for feedback and the use of images, video and audio. The study found that the sampled newspapers do not frequently use links, images, video and audio or give users opportunities to give feedback.

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A Work-Based Window Method For Calculating In-Use Brake-Specific Oxides Of Nitrogen Emissions Of Heavy -Duty Diesel Engines, Benjamin C. Shade May 2006

A Work-Based Window Method For Calculating In-Use Brake-Specific Oxides Of Nitrogen Emissions Of Heavy -Duty Diesel Engines, Benjamin C. Shade

Graduate Theses, Dissertations, and Problem Reports (ETD)

Heavy-duty diesel engines (HDDEs) are currently certified in an engine dynamometer test cell over defined test cycles, such as the Federal Test Procedure (FTP) or the Supplemental Emissions Test (SET). In addition to certification testing, those HDDEs are subjected to in-use testing where gaseous emissions levels are not to exceed 125% of the certification level plus an additional 0.5 g/bhp-hr for instrument and analyzer inaccuracies. These HDDEs are required to meet these limits in the Not-To-Exceed (NTE) zone, which is defined by 40 CFR §86.1370-2007. In this method, emissions are calculated when an engine is operating in the NTE zone …

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Instructors' Self -Perceived Pedagogical Principle Implementation In The Online Environment, Jinsong Zhang May 2006

Instructors' Self -Perceived Pedagogical Principle Implementation In The Online Environment, Jinsong Zhang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to explore and describe the experience of undergraduate faculty members who participated in the practice of online distance instruction. This study explored instructor's perception of their implementation of pedagogical principles in the online environment, identified factors that influenced their implementation of the principles, and explored the relationship between the influencing factors and the online implementation of the Seven Principles.;Research shows that the implementation the Seven Principles for Good Practice in Undergraduate Education (Chickering & Gamson, 1987) varied significantly from one principle to another. Overall the least endorsed of the Seven Principles were Encourage Cooperation …

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Development Of Real Time Roof Geology Detection System Using Drilling Parameters During Roof Bolting Operation, Xianguang Tang May 2006

Development Of Real Time Roof Geology Detection System Using Drilling Parameters During Roof Bolting Operation, Xianguang Tang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal. In fact, all U.S. underground coal mine entries are roof-bolted as required by law.;However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems.;This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting …

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Perceptions Of Faculty And Students Toward The Obstacles Of Implementing E -Government In Educational Institutions In Saudi Arabia, Salah J. M. Alharbi May 2006

Perceptions Of Faculty And Students Toward The Obstacles Of Implementing E -Government In Educational Institutions In Saudi Arabia, Salah J. M. Alharbi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to examine the perceptions of faculty members and students towards the obstacles of e-government implementation in educational institutions in Saudi Arabia. To collect data, the researcher developed two surveys and employed a quantitative research technique. The research population involved 101 faculty members and 305 students from the IPA, KSU and IMBSIU. Descriptive statistics, frequency and percentage were conducted for each variable. Means and standard deviations for all Likert-type scale variables were calculated. Testing for the equality of groups' means was conducted using t-test or Analyses of Variance (ANOVA). The level of significance was 0.05 …

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Detection And Analysis Of Deck Cracks In A Long Span Empirically Designed Bridge Deck Through Embedded Sensory Systems, Mourad Y. Riad May 2006

Detection And Analysis Of Deck Cracks In A Long Span Empirically Designed Bridge Deck Through Embedded Sensory Systems, Mourad Y. Riad

Graduate Theses, Dissertations, and Problem Reports (ETD)

Bridge decks exhibit premature longitudinal and transverse cracks leading to dramatic decrease in their service lives. Because of safety concerns, state highway agencies are overburdened by conducting annual visual inspections to detect signs of distresses in bridge elements and to provide continuous records of the conditions of such bridges. Those inspections are time consuming, and have multiple limitations which often yield controversial outputs. In this study, an instrumentation based system is designed and implemented on the Star City Bridge near Morgantown WV, to provide more sophisticated, and accurate methods to assess the structural performance of bridge elements, and hence provide …

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Multi-Impression Enhancement Of Fingerprint Images, Mayank Agarwal May 2006

Multi-Impression Enhancement Of Fingerprint Images, Mayank Agarwal

Graduate Theses, Dissertations, and Problem Reports (ETD)

Biometric system deals with recognizing a person by determining the authenticity based on physiological and behavioral characteristics. Fingerprints are well known for their distinctiveness among individuals and have been widely used for personal authentication and recognition. This thesis studies the enhancement problem for fingerprint images with marginal quality due to a number of reasons (e.g., scar, moisture, dryness, over-pressure).;Our contribution is two fold. In single-copy enhancement, we have developed an image inpainting based approach to repair low-quality regions in a fingerprint images that are detected by ridge coherence. In multi-copy enhancement, we propose to mosaic multiple copies of the same …

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Partial Oxidation Of Propane On Ceria- And Alumina-Supported Platinum Catalysts, Vijaya Anil Bansode May 2006

Partial Oxidation Of Propane On Ceria- And Alumina-Supported Platinum Catalysts, Vijaya Anil Bansode

Graduate Theses, Dissertations, and Problem Reports (ETD)

Three Pt/CeO2 catalysts and Pt/Al2O3 catalyst were studied for partial oxidation of propane. The 1% Pt/CeO 2 (C) catalyst which was prepared using CeO2 prepared by the decomposition technique showed the highest propane conversion and hydrogen selectivity. The 1% Pt/Al2O3 showed better performance than 1% Pt/CeO2 (C).;The effect of flow rate was studied for 0.01 g and 0.02 g of 1% Pt/CeO 2 (C) and 1% Pt/Al2O3. Oxygen is totally consumed at all flow rates, even at 0.01 g catalyst loading for both catalysts. The total oxidation of propane is taking place first followed by steam reforming along with water …

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Barrier Properties Of Polymer Nanocomposites During Cyclic Sorption-Desorption And Stress-Coupled Sorption Experiments, Suneetha Burla May 2006

Barrier Properties Of Polymer Nanocomposites During Cyclic Sorption-Desorption And Stress-Coupled Sorption Experiments, Suneetha Burla

Graduate Theses, Dissertations, and Problem Reports (ETD)

It is well known that layered silicate nanoparticles, when distributed within the matrix of a polymer, can retard the diffusion of small molecules and improve barrier properties. This has been demonstrated in both sorption and permeation experiments in the past. In order to assess the long-term retention of barrier properties of polymer-layered silicate nanocomposites, it becomes important to study their response to various environmental effects.;The main theme of this investigation is to study the effect of several water exposure cycles and exposure coupled with external tensile stress on the barrier properties of various polymers like vinyl ester, polyester and epoxy …

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