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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Essays On The Publicness Of Education And The Effects Of School Choice On Student Achievement, Kerry A. King Aug 2005

Essays On The Publicness Of Education And The Effects Of School Choice On Student Achievement, Kerry A. King

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation is a collection of papers that focus on the effects of school choice in the education market. The first chapter introduces the concept of school choice and discusses the arguments both for and against its implementation into public education. In addition, this chapter outlines the research agenda for this dissertation. Chapter 2 empirically measures the spillover benefits created by K-12 public education and finds that they are not Pareto-relevant at the margin. Given the results, this chapter also examines the role of school choice in the market for K-12 public education. Chapter 3 provides a brief history of …

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Applications Of The Covering Property Axiom, Andres Millan Millan Aug 2005

Applications Of The Covering Property Axiom, Andres Millan Millan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this work is two-fold. First, we present some consequences of the Covering Property Axiom CPA of Ciesielski and Pawlikowski which captures the combinatorial core of the Sacks' model of the set theory. Second, we discuss the assumptions in the formulation of different versions of CPA.;As our first application of CPA we prove that under the version CPAgamecube of CPA there are uncountable strong gamma-sets on R . It is known that Martin's Axiom (MA) implies the existence of a strong gamma-set on R . Our result is interesting since that CPAgamecube implies the negation of MA.;Next, we …

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Claw -Free Graphs And Line Graphs, Yehong Shao Aug 2005

Claw -Free Graphs And Line Graphs, Yehong Shao

Graduate Theses, Dissertations, and Problem Reports (ETD)

The research of my dissertation is motivated by the conjecture of Thomassen that every 4-connected line graph is hamiltonian and by the conjecture of Tutte that every 4-edge-connected graph has a no-where-zero 3-flow. Towards the hamiltonian line graph problem, we proved that every 3-connected N2-locally connected claw-free graph is hamiltonian, which was conjectured by Ryjacek in 1990; that every 4-connected line graph of an almost claw free graph is hamiltonian connected, and that every triangularly connected claw-free graph G with |E( G)| ≥ 3 is vertex pancyclic. Towards the second conjecture, we proved that every line graph of a 4-edge-connected …

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The Role Of Reinforcement Rate On Fluency, Vennessa L. Walker Aug 2005

The Role Of Reinforcement Rate On Fluency, Vennessa L. Walker

Graduate Theses, Dissertations, and Problem Reports (ETD)

Building skills to high rates and accuracy has been purported to result in fluency, a set of behavioral outcomes identified as retention, endurance, application, problem solving, and stability (REAPS). These outcomes require that the skills persist under changing environmental conditions, and may be conceptualized as examples of resistance to change. As such reinforcement rate should be the critical factor. To test this conceptualization twelve subjects were trained on 5 algebra skills to specified rate and accuracy criteria. Feedback consisting of points, knowledge of results, and corrective feedback was delivered either every 1 or 5 minutes. Stability, application, and problem-solving were …

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The Hyperspace Graph Of Connected Subgraphs, Likin C. Simon Romero Aug 2005

The Hyperspace Graph Of Connected Subgraphs, Likin C. Simon Romero

Graduate Theses, Dissertations, and Problem Reports (ETD)

Given a connected graph G, the hyperspace graph of connected subgraphs C (G) is defined. The graph C (G) is such that every vertex represents a connected subgraph of G. It is shown that every connected graph G has a unique graph C (G). A characterization of a path, a cycle and the 3-star by their corresponding hyperspace graphs of connected subgraphs is shown. A special geometric representation R (G) of C (G) in an euclidean space is presented. A set P (G) is constructed based on R (G). When G is a topological tree, P (G) and the hyperspace …

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Refinement Of Numerical Models And Parametric Study Of Sofc Stack Performance, Andrew C. Burt Aug 2005

Refinement Of Numerical Models And Parametric Study Of Sofc Stack Performance, Andrew C. Burt

Graduate Theses, Dissertations, and Problem Reports (ETD)

The presence of multiple air and fuel channels per fuel cell and the need to combine many cells in series result in complex steady-state temperature distributions within Solid Oxide Fuel Cell (SOFC) stacks. Flow distribution in these channels, when non-uniform, has a significant effect on cell and stack performance. Large SOFC stacks are very difficult to model using full 3-D CFD codes because of the resource requirements needed to solve for the many scales involved. Studies have shown that implementations based on Reduced Order Methods (ROM), if calibrated appropriately, can provide simulations of stacks consisting of more than 20 cells …

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Critical Issues For Predicting Worker Exposure To Gaseous Contaminants In A Wind Tunnel, Jun Li Aug 2005

Critical Issues For Predicting Worker Exposure To Gaseous Contaminants In A Wind Tunnel, Jun Li

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study, three dimensional computational fluid dynamics (CFD) simulations are used to investigate the distribution and level of contaminant concentrations in the breathing zone of a worker when airborne contaminants are released within an arm's-length in front of the worker who has his back to the airflow. The main goals were to numerically evaluate the effect of different factors on the worker exposure and to recommend a turbulence model preferable for this type of simulation. These factors include the body shape, the heat flux from the body, the ventilation intensity, the free stream turbulence, and the unsteadiness. The comparison …

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Differences Among Standardized Test Scores Due To Factors Of Internet Access At Home And Family Affluence, Steve Macho Aug 2005

Differences Among Standardized Test Scores Due To Factors Of Internet Access At Home And Family Affluence, Steve Macho

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to examine differences among the standardized test scores of students due to factors of Internet access at home, household income, and the highest level of education attained by mother, father or guardian. If students with Internet access at home have a different academic standing, is it the result of the Internet connection or confounding factors of family affluence?;The San Miguel GEAR UP program at New Mexico Highlands University, located in Las Vegas, New Mexico had existent data on program participants for Internet access at home, household income, highest level of education in the household, …

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Mesh Generation For Voxel -Based Objects, Hanzhou Zhang Aug 2005

Mesh Generation For Voxel -Based Objects, Hanzhou Zhang

Graduate Theses, Dissertations, and Problem Reports (ETD)

A new physically-based approach to unstructured mesh generation via Monte-Carlo simulation is proposed. Geometrical objects to be meshed are represented by systems of interacting particles with a given interaction potential. A new way of distributing nodes in complex domains is proposed based on a concept of dynamic equilibrium ensemble, which represents a liquid state of matter. The algorithm is simple, numerically stable and produces uniform node distributions in domains of complex geometries and different dimensions. Well-shaped triangles or tetrahedra can be created by connecting a set of uniformly-spaced nodes. The proposed method has many advantages and potential applications.;The new method …

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Reservoir Characterization Using Intelligent Seismic Inversion, F. Emre Artun Aug 2005

Reservoir Characterization Using Intelligent Seismic Inversion, F. Emre Artun

Graduate Theses, Dissertations, and Problem Reports (ETD)

Integrating different types of data having different scales is the major challenge in reservoir characterization studies. Seismic data is among those different types of data, which is usually used by geoscientists for structural mapping of the subsurface and making interpretations of the reservoir's facies distribution. Yet, it has been a common aim of geoscientists to incorporate seismic data in high-resolution reservoir description through a process called seismic inversion.;In this study, an intelligent seismic inversion methodology is presented to achieve a desirable correlation between relatively low-frequency seismic signals, and the much higher frequency wireline-log data. Vertical seismic profile (VSP) is used …

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Crisis Manager Of The American Revolution: Henry Laurens, Jeffrey R. Gudzune Aug 2005

Crisis Manager Of The American Revolution: Henry Laurens, Jeffrey R. Gudzune

Graduate Theses, Dissertations, and Problem Reports (ETD)

As President of the Continental Congress, Henry Laurens was a firm leader amid a time of national emergency. When a dispute within the Continental Army threatened both the continuation of General Washington's command and the American alliance with France, Laurens went beyond his limited sphere of political authority to settle the matter. When a peace commission from England arrived in the United States to begin discussing terms for an end to the hostilities, Laurens found himself in an increasingly difficult diplomatic situation. While wrestling with the question of whether or not to accept the British offer, Laurens was also forced …

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Development Of An Indentation Method For Material Surface Mechanical Properties Measurement, Ziheng Yao May 2005

Development Of An Indentation Method For Material Surface Mechanical Properties Measurement, Ziheng Yao

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the utilizing structural materials with small size dimensions (such as MEMS devices), there are growing need to characterize the mechanical properties of the small volumes of materials. Tensile test is not possible to be applied to these small volumes. Indentation technique has emerged as a cost-effective, convenient and non-destructive method to solve this problem. It is also a promising means of obtaining mechanical properties for thin films, which were widely used in various industries nowadays.;In this work, finite element simulations of spherical indentation on various material models were performed to develop a series of methodology, by which the material …

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Steady State Thermal Stress Analyses Of Two-Dimensional And Three-Dimensional Solid Oxide Fuel Cells, Srividya Valluru May 2005

Steady State Thermal Stress Analyses Of Two-Dimensional And Three-Dimensional Solid Oxide Fuel Cells, Srividya Valluru

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fuel cells are electrochemical devices which convert fuels directly into electrical energy without combustion. The Solid Oxide Fuel Cell (SOFC) is the most promising energy saving technology to generate electric power. The present work characterizes the thermal stresses arising during the operation of planar solid oxide fuel cells which is a critical factor in the development of an efficient fuel cell. The thermal stresses are calculated from the temperature fields using ANSYS(TM). A sequentially coupled thermal stress analysis approach is implemented for the two-dimensional five stack fuel cell model and a structural analysis for the three-dimensional single stack fuel cell. …

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Forced Vibration And Hygrothermal Analysis Of Composite Laminated Beams Under The Action Of Moving Loads, Praveen Kumar Kavipurapu May 2005

Forced Vibration And Hygrothermal Analysis Of Composite Laminated Beams Under The Action Of Moving Loads, Praveen Kumar Kavipurapu

Graduate Theses, Dissertations, and Problem Reports (ETD)

The dynamic response of simply supported glass/epoxy composite beams subjected to moving loads in a hygrothermal environment is carried out using the general purpose finite element program ANSYS. The moving load model and the hygrothermal incorporation are validated separately by reproducing results available in the literature. The hygrothermal effect is introduced by using empirical relations for degrading the material stiffness properties of the matrix. The corresponding ply properties are calculated using the rule of mixtures. A parametric study is conducted by varying the fiber volume fraction and the fiber orientation of the angle plies in the laminate. The results indicate …

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Text-Independent Speaker Recognition, Smitha Gangisetty May 2005

Text-Independent Speaker Recognition, Smitha Gangisetty

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research presents new text-independent speaker recognition system with multivariate tools such as Principal Component Analysis (PCA) and Independent Component Analysis (ICA) embedded into the recognition system after the feature extraction step. The proposed approach evaluates the performance of such a recognition system when trained and used in clean and noisy environments. Additive white Gaussian noise and convolutive noise are added. Experiments were carried out to investigate the robust ability of PCA and ICA using the designed approach. The application of ICA improved the performance of the speaker recognition model when compared to PCA. Experimental results show that use of …

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Measurement And Evaluation Of The Performance Of An Integral Abutment Bridge Deck, Kenneth Mcgowan May 2005

Measurement And Evaluation Of The Performance Of An Integral Abutment Bridge Deck, Kenneth Mcgowan

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis is based upon the instrumentation of an integral abutment bridge, with a reinforced concrete deck on 3-span, continuous steel girders. The bridge is located in Evansville, West Virginia, at the intersection of WV Route 92 South and US Route 50 East. An instrumentation system was developed to measure the performance of the bridge, including a system of 30 crack meters installed in the deck to detect cracks, strain gages on the girders and embedded in the deck, whose readings can be utilized to determine the degree of composite action of the deck and girders, and sister bars to …

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Investigation Of Fabrication Process Development For Integrated Optical Grating Structures, Divya Pisharoty May 2005

Investigation Of Fabrication Process Development For Integrated Optical Grating Structures, Divya Pisharoty

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sub-micron optical gratings are essential integrated elements to couple light into waveguides and for optical monitoring of microfluidic channels or MEMS devices. Since the required features in the sub-micron regime are difficult to achieve by mechanical ruling and photolithography, alternate fabrication techniques are investigated. Exposure by e-beam and laser are two direct write methods which are used. These methods preclude the need of a mask, require few processing steps, and can be used to write features of sizes desired for optical gratings. In this research, we explore and develop processes to create sub-micron gratings by both these methods. A resist …

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Enumeration Of The Generalized Catalan Numbers, Steven L. Richardson Jr. May 2005

Enumeration Of The Generalized Catalan Numbers, Steven L. Richardson Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

The sequence of numbers given by the equation Cn=1n +12nn are widely known as the Catalan numbers, because they were first studied by Catalan. The ways to enumerate these numbers are similarly widely known and studied, as can be seen in Gould's catalog of Catalan numbers. Our objective is to find ways to enumerate this larger and generalized set of sequences, using multiple methods that will build on known enumerations of the Catalan numbers.

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Non-Technical Skills And Traits Needed To Be Career-Ready Graduates As Perceived By Agribusiness Employers And Recruiters, Thomas H. Brand Iii May 2005

Non-Technical Skills And Traits Needed To Be Career-Ready Graduates As Perceived By Agribusiness Employers And Recruiters, Thomas H. Brand Iii

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of the study was to determine the skills needed by students of the Davis College of Agriculture, Forestry, and Consumer Sciences to secure employment after graduation. The population consisted of 211 agribusiness employers who have attended the College's Biannual Career Fairs. A descriptive research design was used for this study. A major finding of this study was employers rated graduates based on means as somewhat prepared or not prepared in several communication skills, business skills and business abilities. Employers also rated Davis College graduates in general to college graduates in preparation level for entry level employment. There were …

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Multi-Agent Control And Operation Of Electric Power Distribution Systems, Amer Al-Hinai May 2005

Multi-Agent Control And Operation Of Electric Power Distribution Systems, Amer Al-Hinai

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation presents operation and control strategies for electric power distribution systems containing distributed generators. First, models of microturbines and fuel cells are developed. These dynamic models are incorporated in a power system analysis package. Second, operation of these generators in a distribution system is addressed and load following schemes are designed. The penetration of distributed generators (DGs) into the power distribution system stability becomes an issue and so the control of those DGs becomes necessary. A decentralized control structure based on conventional controllers is designed for distributed generators using a new developed optimization technique called Guided Particle Swarm Optimization. …

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Finite-Element Modeling Of A Composite Bridge Deck, Suraj Suraj May 2005

Finite-Element Modeling Of A Composite Bridge Deck, Suraj Suraj

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber Reinforced Polymer (FRP) materials are being widely used for structural applications, an example being bridge decks. In this study a finite-element model using the software ANSYS is developed for an 8&inches;-thick low-profile FRP bridge deck (Prodeck 8) made of E-glass fiber and Polyester resin. The bridge deck is subjected to a patch load at the center and the finite-element results obtained in the form of deflections, strains, and equivalent flexural rigidity are compared with experimental results. A good correlation is found to exist between the finite-element results and the experimental results. A failure analysis, based on maximum stress, maximum …

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Noise And Error Propagation In Diffusion Tensor Imaging, Shital Bipin Desai May 2005

Noise And Error Propagation In Diffusion Tensor Imaging, Shital Bipin Desai

Graduate Theses, Dissertations, and Problem Reports (ETD)

Diffusion Tensor Imaging (DTI) is the in vivo visualization and analysis of white matter fiber tracts by measuring the anisotropy of water molecule diffusion in the brain tissue. DTI has been increasingly used in clinical imaging. Diffusion weighted images are affected by noise from the human subject and the MRI scanner. This thesis studies the error propagation in the calculation of the DTI invariant anisotropy, mainly the Fractional Anisotropy (FA) using four methods and their comparison in terms of error, filtering and computational efficiency using simulated and human brain data. These methods were Diffusion Tensor, Diffusion Ellipsoid, Hasan and Platonic …

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Shared Decision-Making And Its Impact On Inclusion For Special Needs Students, Deborah E. Kuhns May 2005

Shared Decision-Making And Its Impact On Inclusion For Special Needs Students, Deborah E. Kuhns

Graduate Theses, Dissertations, and Problem Reports (ETD)

Shared decision-making is a style of leadership that affords ownership, empowerment, and being part of a team that can make a difference. When the Individuals with Disabilities Education Act (IDEA) required a committee to develop an Individualized Education Program, inclusion was considered in order to provide the least restrictive environment within which the student could make progress in a school setting.;When the regular classroom teachers feel that they help to make decisions for inclusion of children in their classrooms, does it impact their implementation of inclusion? Regular classroom teachers were interviewed for this case study to determine how shared decision-making …

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Experimental Investigation Of Oscillatory Heat Release Mechanisms And Stability Margin Analysis In Lean -Premixed Combustion, Don H. Ferguson May 2005

Experimental Investigation Of Oscillatory Heat Release Mechanisms And Stability Margin Analysis In Lean -Premixed Combustion, Don H. Ferguson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Lean-premixed combustion has become an acceptable means of achieving ultra-low NOx emissions from land-based gas turbines. Further reduction may be possible through the use of hydrogen augmented or syngas fuels. However, advanced combustor designs developed to utilize these technologies often encounter thermoacoustic instabilities that may significantly hamper engine performance and shorten component life-cycles. These dynamics, although not fully understood, occur through a complex interaction between variations in heat release rate and acoustic properties of the system, and can be exacerbated by variable fuel properties in natural gas and syngas applications.;Theoretical models of thermoacoustic instabilities have attempted to describe the coupling …

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Numerical Simulation Of Continuous Miner Rock Cutting Process, Bo Yu May 2005

Numerical Simulation Of Continuous Miner Rock Cutting Process, Bo Yu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Usually, parametric analysis of the continuous miner cutting process is studied by experimental tests. In this dissertation, the need for numerical simulation of the continuous miner rock cutting process is established. In order to fulfill this need, four major numerical methods, namely the Finite Difference Method, the Finite Element Method, the Boundary Element Method, and the Discrete Element Method, are reviewed. The Finite Element Method is then chosen as the simulation tool because it is more advanced and versatile than the other methods.;The rotation and advance of a continuous miner cutter head is simulated by the Finite Element Method with …

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Development Of Constant-Time Correlated Spectroscopy On A 3t Clinical Mri/Mrs Scanner, Srilatha Ainala May 2005

Development Of Constant-Time Correlated Spectroscopy On A 3t Clinical Mri/Mrs Scanner, Srilatha Ainala

Graduate Theses, Dissertations, and Problem Reports (ETD)

Magnetic Resonance Spectroscopy (MRS) is widely used both as a fundamental research technique, as well as diagnostic tool in medical research providing unique information about the metabolites. In this thesis, we report our work on the development of novel localized constant-time correlated Magnetic Resonance Spectroscopic technique for resolving the overlapping metabolites and also to improve the quantification strategies. The new sequence was implemented on a GE 3T MRI/MRS scanner. The underlying spin dynamics is discussed for a two-spin ½ system with a J coupling. We demonstrate the coherence transfer to cross peaks and diagonal peaks by changing the constant time. …

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Localized Double-Quantum Filtered Correlated Spectroscopy On 3t Mri/Mrs Scanner, Senthil Ramamurthy May 2005

Localized Double-Quantum Filtered Correlated Spectroscopy On 3t Mri/Mrs Scanner, Senthil Ramamurthy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Standard localized magnetic resonance spectroscopic sequences employ single quantum coherences for excitation and detection. This results in a complex spectra containing large number of resonances. In this thesis we have developed a novel volume localized spectroscopic technique that excites multiple quantum coherences in coupled spin clusters (metabolites) and then reconvert them into single quantum coherences for detection. This results in filtering of uncoupled resonances and also suppresses water with high efficiency. The resulting spectra is reduced in complexity due to the absence of uncoupled resonances.;The technique has been developed in volume localized mode and implemented on a 3T scanner. The …

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Fourth Graders' Development Of Multimedia Portfolios., Veronica D. Kuminkoski-Yurt Jan 2005

Fourth Graders' Development Of Multimedia Portfolios., Veronica D. Kuminkoski-Yurt

Graduate Theses, Dissertations, and Problem Reports (ETD)

A review of the literature indicates there is a need for alternative assessment practices for elementary students. Seven fourth grade students in a small rural school will learn how to construct an electronic portfolio that will exhibit their progress and achievement. The contents of the portfolio must include student participation in the selection as well as provide evidence of self-reflection. This study researches a computer-based portfolio, which uses HyperStudio software. This program will allow students to create sound, video, graphics, and animation during the construction process. As students build their multimedia portfolios, they will learn how to use technology as …

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The Instructional Control Of Problem Solving: Emergent Relations And Blending Of Repertoires., Harold E. Lobo Jan 2005

The Instructional Control Of Problem Solving: Emergent Relations And Blending Of Repertoires., Harold E. Lobo

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study investigated the effects of strategic and tactical instructions on emergent stimulus relations. Sixteen female college students completed a linear-series baseline training with three potential equivalence classes of five members each. After successfully completing baseline training, participants completed repeated blocks of testing with probes for all possible emerging relations. Six participants performed below 70% correct on these probes. Three of these participants received subsequent training with a strategic instruction, whereas the remaining three participants were trained with tactical instructions. Afterwards, these six participants resumed repeated testing. Performance of participants who received the strategic instruction improved significantly, with correct responding …

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An Attack-Resistant Approach To Vulnerability Scanner Design., David Phillip Shaver Jan 2005

An Attack-Resistant Approach To Vulnerability Scanner Design., David Phillip Shaver

Graduate Theses, Dissertations, and Problem Reports (ETD)

Vulnerability scanners are used to scan and detect known vulnerabilities in computer systems. An attacker can exploit these vulnerabilities to compromise the security of a system and potentially cause harm. Thus, it is vital to detect and repair any vulnerabilities that exist. Vulnerability scanners, however, are themselves susceptible to attack. If an attacker were to compromise a scanner, they could force it ignore the vulnerabilities of other systems. They could then compromise these other computers by exploiting the undetected vulnerabilities. Due to the importance of preventing such false positives in scan results, this research proposes a new approach to vulnerability …

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