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2010

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Articles 2821 - 2850 of 8620

Full-Text Articles in Physical Sciences and Mathematics

Developing A Hybrid Virtualization Platform Design For Cyber Warfare And Simulation, Kyle E. Stewart Jun 2010

Developing A Hybrid Virtualization Platform Design For Cyber Warfare And Simulation, Kyle E. Stewart

Theses and Dissertations

Virtualization is a technique used to model and simulate the cyber domain, as well as train and educate. Different types of virtualization techniques exist that each support a unique set of benefits and requirements. This research proposes a novel design that incorporates host and network virtualization concepts for a cyber warfare training platform. At the host level, hybrid virtualization combines full and operating system virtualization techniques in order to leverage the benefits and minimize the drawbacks of each individual technique. Network virtualization allows virtual machines to connect in flexible topologies, but it also incurs additional processing overhead. Quantitative analysis falls …

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Electronic Structure Of Lithium Tetraborate, David J. Wooten Jun 2010

Electronic Structure Of Lithium Tetraborate, David J. Wooten

Theses and Dissertations

Due to interest as neutron detection material, an investigation of Li2B4O7(110) and Li2B4O7(100) was undertaken, utilizing photoemission and inverse photoemission spectroscopic techniques. The measured band gap depended on crystallographic direction with the band gaps ranging from 8.9±0.5 eV to 10.1±0.5 eV. The measurement yielded a density of states that qualitatively agreed with the theoretical results from model bulk band structure calculations for Li2B4O7; albeit with a larger band gap than predicted, but consistent with the known deficiencies of LDA and DFT calculations. …

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Deterministic, Efficient Variation Of Circuit Components To Improve Resistance To Reverse Engineering, Daniel F. Koranek Jun 2010

Deterministic, Efficient Variation Of Circuit Components To Improve Resistance To Reverse Engineering, Daniel F. Koranek

Theses and Dissertations

This research proposes two alternative methods for generating semantically equivalent circuit variants which leave the circuit's internal structure pseudo-randomly determined. Component fusion deterministically selects subcircuits using a component identification algorithm and replaces them using a deterministic algorithm that generates canonical logic forms. Component encryption seeks to alter the semantics of individual circuit components using an encoding function, but preserves the overall circuit semantics by decoding signal values later in the circuit. Experiments were conducted to examine the performance of component fusion and component encryption against representative trials of subcircuit selection-and-replacement and Boundary Blurring, two previously defined methods for circuit obfuscation. …

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An Application Of Automated Theorem Provers To Computer System Security: The Schematic Protection Model, Mitchell D.I. Hirschfeld Jun 2010

An Application Of Automated Theorem Provers To Computer System Security: The Schematic Protection Model, Mitchell D.I. Hirschfeld

Theses and Dissertations

The Schematic Protection Model is specified in SAL and theorems about Take-Grant and New Technology File System schemes are proven. Arbitrary systems can be specified in SPM and analyzed. This is the first known automated analysis of SPM specifications in a theorem prover. The SPM specification was created in such a way that new specifications share the underlying framework and are configurable within the specifications file alone. This allows new specifications to be created with ease as demonstrated by the four unique models included within this document. This also allows future users to more easily specify models without recreating the …

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The Combined Effects Of Radio Frequency And Gamma Irradiation On P-Channel Mosfets, Joshua D. Daniel Jun 2010

The Combined Effects Of Radio Frequency And Gamma Irradiation On P-Channel Mosfets, Joshua D. Daniel

Theses and Dissertations

The purpose of this research was to investigate the combined effects of continuous gigahertz radio frequency signals and gamma irradiation on the threshold voltage of metal oxide semiconductor field effect transistors. The combined effects of gigahertz radio frequency waves and gamma irradiation on electronics presents a new challenge in electronic warfare and little is known of the combined effect on threshold voltage damage and recovery. The Fairchild NDS352AP, a commonly used commercial device, was irradiated by a cobalt-60 source under a +5 V bias with and without a radio frequency signal applied to the gate. The threshold voltage was measured …

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Realistic Vertical Atmospheric Profiles And Effects From Limited Surface Observations, Dane P. Ranney Jun 2010

Realistic Vertical Atmospheric Profiles And Effects From Limited Surface Observations, Dane P. Ranney

Theses and Dissertations

The ability to accurately describe the atmospheric conditions around us is not only important to the Air Force, but to anyone involved in signal propagation. The programs currently utilized to describe the atmosphere take into account a variety of measures. The LEEDR (Laser Environmental Effects Definition and Reference) program in particular, allows the user to select a location, aerosol and molecular effects model, numerous cloud and precipitation events, as well as other features. Even with the control that the user has, the output that the program provides can vary from actual conditions on a day to day basis. This is …

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Sediment Flux Through The Rio Grande River: A Monsoonal Effect, Troy C. Hiatt Jun 2010

Sediment Flux Through The Rio Grande River: A Monsoonal Effect, Troy C. Hiatt

Theses and Dissertations

Climate has historically been recognized as an influence on sediment flux and deposition. The North American Monsoon is suggested as the forcing mechanism of deltaic progradational events of the Rio Grande River delta. Interpretations of reflection seismic profiles reveal that eustatic rise in sea-level from the Last Glacial Maximum to present is accompanied by several regressional events of the Rio Grande delta 5.5, 9.5, and 11.5 ka BP. Much of the migration of depositional facies within a delta system is forced by hinterland tectonics and base-level rise and fall. However, we suggest that the movement of facies within the Rio …

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Atmospheric Airglow Fluctuations Due To A Tsunami‐Driven Gravity Wave Disturbance, Michael P. Hickey Ph.D., G. Schubert, R. L. Walterscheid Jun 2010

Atmospheric Airglow Fluctuations Due To A Tsunami‐Driven Gravity Wave Disturbance, Michael P. Hickey Ph.D., G. Schubert, R. L. Walterscheid

Publications

A spectral full‐wave model is used to study the upward propagation of a gravity wave disturbance and its effect on atmospheric nightglow emissions. Gravity waves are generated by a surface displacement that mimics a tsunami having a maximum amplitude of 0.5 m, a characteristic horizontal wavelength of 400 km, and a horizontal phase speed of 200 m/s. The gravity wave disturbance can reach F region altitudes before significant viscous dissipation occurs. The response of the OH Meinel nightglow in the mesopause region (∼87 km altitude) produces relative brightness fluctuations, which are ∼1% of the mean for overhead viewing. The wave …

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Hidra: Hierarchical Inter-Domain Routing Architecture, Bryan Clevenger, Daniel Nelson, John M. Bellardo Jun 2010

Hidra: Hierarchical Inter-Domain Routing Architecture, Bryan Clevenger, Daniel Nelson, John M. Bellardo

Computer Science and Software Engineering

The size of the Internet’s forwarding table is growing rapidly, generating concerns about the ability for high performance routing equipment to economically keep pace. The primary contributors to this growth are end site multihoming, traffic engineering, and in the foreseeable future, IPv6 deployment. This paper presents HIDRA, a hierarchal network architecture designed to reduce both the immediate size of the Internet’s forwarding table as well as its growth rate while maximizing compatibility with the existing In ternet architecture. This includes the ability to use exist ing high performance routers, existing routing protocols, and existing number allocation policies. HIDRA is prototyped …

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Stable Amorphous Blue Phase Of Bent-Core Nematic Liquid Crystals Doped With A Chiral Material, Stefanie Taushanoff, Khoa Le, Jarrod Williams, Robert Twieg, B. Sadashiva, Hideo Takezoe, Antal Jakli Jun 2010

Stable Amorphous Blue Phase Of Bent-Core Nematic Liquid Crystals Doped With A Chiral Material, Stefanie Taushanoff, Khoa Le, Jarrod Williams, Robert Twieg, B. Sadashiva, Hideo Takezoe, Antal Jakli

Antal Jakli

We report an induction of the blue phase III (BPIII) at a relatively low and wide ( over 20 degrees C) temperature range in nematogenic achiral bent-core liquid crystals doped with a high twisting power chiral material. The pitch decreases with increasing chiral dopant ratio, and easily reaches the ultraviolet wavelength, so that completely dark texture is obtained under crossed polarizers. Electrooptical switching was achieved in a time range of a few to a few tens of milliseconds. We propose for the stabilization of BPIII that broad-temperature range smectic nano-clusters inhibit the long-range order of the double twisted helical structures, …

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Multi-State Life Tables, Equilibrium Prevalence, And Baseline Selection Bias, Paula Diehr, David Yanez Jun 2010

Multi-State Life Tables, Equilibrium Prevalence, And Baseline Selection Bias, Paula Diehr, David Yanez

UW Biostatistics Working Paper Series

Consider a 3-state system with one absorbing state, such as Healthy, Sick, and Dead. If the system satisfies the 1-step Markov conditions, the prevalence of the Healthy state will converge to a value that is independent of the initial distribution. This equilibrium prevalence and its variance are known under the assumption of time homogeneity, and provided reasonable estimates in the time non-homogeneous systems studied. Here, we derived the equilibrium prevalence for a system with more than three states. Under time homogeneity, the equilibrium prevalence distribution was shown to be an eigenvector of a partition of the matrix of transition probabilities. …

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Continuous Generation Of Soliton Patterns In Two-Dimensional Dissipative Media By Razor, Dagger, And Needle Potentials, B Liu, Yj He, Ba Malomed, Xs Wang, Pg Kevrekidis, Tb Wang, Fc Leng, Zr Qiu, Hz Wang Jun 2010

Continuous Generation Of Soliton Patterns In Two-Dimensional Dissipative Media By Razor, Dagger, And Needle Potentials, B Liu, Yj He, Ba Malomed, Xs Wang, Pg Kevrekidis, Tb Wang, Fc Leng, Zr Qiu, Hz Wang

Panos Kevrekidis

We report dynamic regimes supported by a sharp quasi-one-dimensional (1D) (“razor”), pyramid-shaped (“dagger”), and conical (“needle”) potentials in the 2D complex Ginzburg–Landau (CGL) equation with cubic-quintic nonlinearity. This is a model of an active optical medium with respective expanding antiwaveguiding structures. If the potentials are strong enough, they give rise to continuous generation of expanding soliton patterns by a 2D soliton initially placed at the center. In the case of the pyramidal potential with M edges, the generated patterns are sets of M jets for M≤5, or expanding polygonal chains of solitons for M≥6. In the conical geometry, these are …

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2010 Adaptive Management Report, Desert Conservation Program Jun 2010

2010 Adaptive Management Report, Desert Conservation Program

Publications (C)

The Desert Conservation Program administers the incidental take permit issued in 2001 by the United States Fish and Wildlife Service in accordance with the Endangered Species Act. Compliance with the permit requires implementation of the Clark County Multiple Species Habitat Conservation Plan. This plan requires an adaptive management program and a biennial report by an independent science advisor to assess the status of the plan and make recommendations for future funding. This 2010 Adaptive Management Report reviews current data on land use trends, habitat loss, species status and plan implementation, and makes recommendations for the future.

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Semantically Annotated Restful Services For Large-Scale Metabolomics Data Analysis, Ashwin Manjunatha, Paul E. Anderson, Satya S. Sahoo, Ajith H. Ranabahu, Michael L. Raymer, Amit P. Sheth Jun 2010

Semantically Annotated Restful Services For Large-Scale Metabolomics Data Analysis, Ashwin Manjunatha, Paul E. Anderson, Satya S. Sahoo, Ajith H. Ranabahu, Michael L. Raymer, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

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Orally Bioavailable Dual Mmp-1/Mmp-14 Sparing, Mmp-13 Selective Alpha-Sulfone Hydroxamates, Daniel Becker, Stephen A. Kolodziej, Susan L. Hockerman, Terri L. Boehm, Jeffery N. Carroll Jun 2010

Orally Bioavailable Dual Mmp-1/Mmp-14 Sparing, Mmp-13 Selective Alpha-Sulfone Hydroxamates, Daniel Becker, Stephen A. Kolodziej, Susan L. Hockerman, Terri L. Boehm, Jeffery N. Carroll

Chemistry: Faculty Publications and Other Works

A series of phenyl piperidine α-sulfone hydroxamate derivatives has been prepared utilizing a combination of solution-phase and resin-bound library technologies to afford compounds that are potent and highly selective for MMP-13, are dual-sparing of MMP-1 and MMP-14 (MT1-MMP) and exhibit oral bioavailability in rats.

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Immobilization Of Polymer-Decorated Liquid Crystal Droplets On Chemically Tailored Surfaces, Michael I. Kinsinger, Maren E. Buck, Nicholas L. Abbott, David M. Lynn Jun 2010

Immobilization Of Polymer-Decorated Liquid Crystal Droplets On Chemically Tailored Surfaces, Michael I. Kinsinger, Maren E. Buck, Nicholas L. Abbott, David M. Lynn

Chemistry: Faculty Publications

We demonstrate that the assembly of an amphiphilic polyamine on the interfaces of micrometer-sized droplets of a thermotropic liquid crystal (LC) dispersed in aqueous solutions can be used to facilitate the immobilization of LC droplets on chemically functionalized surfaces. Polymer 1 was designed to contain both hydrophobic (alkylfunctionalized) and hydrophilic (primary and tertiary amine-functionalized) side chain functionality. The assembly of this polymer at the interfaces of aqueous dispersions of LC droplets was achieved by the spontaneous adsorption of polymer from aqueous solution. Polymer adsorption triggered transitions in the orientational ordering of the LCs, as observed by polarized light and bright-field …

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Bead Modeling Of Transport Properties Of Macromolecules In Free Solution And In A Gel, Hongxia Pei Jun 2010

Bead Modeling Of Transport Properties Of Macromolecules In Free Solution And In A Gel, Hongxia Pei

Chemistry Dissertations

On the bead modeling methodology, or BMM, a macromolecule is modeled as a rigid, non-overlapping bead array with arbitrary radii. The BMM approach was pioneered by Kirkwood and coworkers (Kirkwood, J.G., Macromolecules, E.P. Auer (Ed.), Gordon and Breach, New York, 1967; Kirkwood, J.G., Riseman, J., J. Chem. Phys., 1948, 16, 565) and applied to such transport properties as diffusion, sedimentation, and viscosity. With the availability of computers, a number of investigators extended the work to account for the detailed shape of biomolecules in the 1970s. A principle objective of my research has been to apply the BMM approach to more …

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Synthesis Of 5-Azaindoles Via A Cycloaddition Reaction Between Nitriles And Donor-Acceptor Cyclopropanes., Mahmoud M Abd Rabo Moustafa, Brian L Pagenkopf Jun 2010

Synthesis Of 5-Azaindoles Via A Cycloaddition Reaction Between Nitriles And Donor-Acceptor Cyclopropanes., Mahmoud M Abd Rabo Moustafa, Brian L Pagenkopf

Chemistry Publications

A new method for the synthesis of 5-azaindole derivatives is reported. A [3+2] dipolar cycloaddition between nitriles and a 3,4-cyclopropanopiperidine followed by SeO(2) oxidation affords the target compounds in moderate to excellent yields. The divergent nature and cost effectiveness of this method makes it very suitable for combinatorial applications in the pharmaceutical industry.

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Mmp-13 Selective Isonipecotamide Alpha-Sulfone Hydroxamates, Stephen A. Kolodziej, Susan L. Hockerman, Gary A. Decrescenzo, Joseph J. Mcdonald, Grace E. Munie, Theresa R. Fletcher, Nathan Stehle, Craig Swearingen, Daniel Becker Jun 2010

Mmp-13 Selective Isonipecotamide Alpha-Sulfone Hydroxamates, Stephen A. Kolodziej, Susan L. Hockerman, Gary A. Decrescenzo, Joseph J. Mcdonald, Grace E. Munie, Theresa R. Fletcher, Nathan Stehle, Craig Swearingen, Daniel Becker

Chemistry: Faculty Publications and Other Works

A series of N-aryl isonipecotamide α-sulfone hydroxamate derivatives has been prepared utilizing a combination of solution-phase and resin-bound library technologies to afford compounds that are potent and highly selective for MMP-13.

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The Arctic Research Of The Composition Of The Troposphere From Aircraft And Satellites (Arctas) Mission: Design, Execution, And First Results, D J. Jacob, J H. Crawford, H Maring, A D. Clarke, Jack E. Dibb, L K. Emmons, R A. Ferrare, C A. Hostetler, Phil Russell, H B. Singh, A M. Thompson, G E. Shaw, E Mccauley, Judith Pederson, Jenny Fisher Jun 2010

The Arctic Research Of The Composition Of The Troposphere From Aircraft And Satellites (Arctas) Mission: Design, Execution, And First Results, D J. Jacob, J H. Crawford, H Maring, A D. Clarke, Jack E. Dibb, L K. Emmons, R A. Ferrare, C A. Hostetler, Phil Russell, H B. Singh, A M. Thompson, G E. Shaw, E Mccauley, Judith Pederson, Jenny Fisher

Earth Sciences

The NASA Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) mission was conducted in two 3-week deployments based in Alaska (April 2008) and western Canada (June–July 2008). Its goal was to better understand the factors driving current changes in Arctic atmospheric composition and climate, including (1) influx of mid-latitude pollution, (2) boreal forest fires, (3) aerosol radiative forcing, and (4) chemical processes. The June–July deployment was preceded by one week of flights over California (ARCTAS-CARB) focused on (1) improving state emission inventories for greenhouse gases and aerosols, (2) providing observations to test and improve models …

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Debye Series For Light Scattering By A Coated Nonspherical Particle, Feng Xu, James A. Lock Jun 2010

Debye Series For Light Scattering By A Coated Nonspherical Particle, Feng Xu, James A. Lock

Physics Faculty Publications

By using the extended boundary condition method, the Debye series is developed for light scattered by a coated nonspherical particle in order to interpret the angular dependence of the scattered intensity in terms of various physical processes. Numerical calculations are performed to study the influence of the coating thickness and the ellipticity of a coated spheroid on the angular position of the alpha and beta primary rainbows, which are produced by partial waves experiencing one internal reflection. The hyperbolic umbilic focal section is demonstrated and is analyzed for both the alpha and the beta rainbows.

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Global Optimization For Value Function Approximation, Marek Petrik, Shlomo Zilberstein Jun 2010

Global Optimization For Value Function Approximation, Marek Petrik, Shlomo Zilberstein

Shlomo Zilberstein

Existing value function approximation methods have been successfully used in many applications, but they often lack useful a priori error bounds. We propose a new approximate bilinear programming formulation of value function approximation, which employs global optimization. The formulation provides strong a priori guarantees on both robust and expected policy loss by minimizing specific norms of the Bellman residual. Solving a bilinear program optimally is NP-hard, but this is unavoidable because the Bellman-residual minimization itself is NP-hard. We describe and analyze both optimal and approximate algorithms for solving bilinear programs. The analysis shows that this algorithm offers a convergent generalization …

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Heat-Balance Integral To Fractional (Half-Time) Heat Diffusion Sub-Model, Jordan Hristov Jun 2010

Heat-Balance Integral To Fractional (Half-Time) Heat Diffusion Sub-Model, Jordan Hristov

Jordan Hristov

The fractional (half-time) sub-model of the heat diffusion equation, known as Dirac-like evolution diffusion equation has been solved by the heat-balance integral method and a parabolic pro file with unspecified exponent. The fractional heat-balance integral method has been tested with two classic examples: fixed temperature and fixed flux at the boundary. The heat-balance technique allows easily the convolution integral of the fractional half-time derivative to be solved as a convolution of the time-independent approximating function. The fractional sub-model provides an artificial boundary condition at the boundary that closes the set of the equations required to express all parameters of the …

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Exploring The Social Implications Of Location Based Social Networking: An Inquiry Into The Perceived Positive And Negative Impacts Of Using Lbsn Between Friends, Sarah Jean Fusco, K. Michael, M.G. Michael Jun 2010

Exploring The Social Implications Of Location Based Social Networking: An Inquiry Into The Perceived Positive And Negative Impacts Of Using Lbsn Between Friends, Sarah Jean Fusco, K. Michael, M.G. Michael

Professor Katina Michael

Location based social networking (LBSN) applications are part of a new suite of emerging social networking tools that run on the Web 2.0 platform. LBSN is the convergence between location based services (LBS) and online social networking (OSN). LBSN applications offer users the ability to look up the location of another “friend” remotely using a smart phone, desktop or other device, anytime and anywhere. Users invite their friends to participate in LBSN and there is a process of consent that follows. Friends have the ability to alter their privacy settings to allow their location to be monitored by another at …

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Exploring The Social Implications Of Location Based Social Networking: An Inquiry Into The Perceived Positive And Negative Impacts Of Using Lbsn Between Friends, Sarah Jean Fusco, K. Michael, M.G. Michael Jun 2010

Exploring The Social Implications Of Location Based Social Networking: An Inquiry Into The Perceived Positive And Negative Impacts Of Using Lbsn Between Friends, Sarah Jean Fusco, K. Michael, M.G. Michael

M. G. Michael

Location based social networking (LBSN) applications are part of a new suite of emerging social networking tools that run on the Web 2.0 platform. LBSN is the convergence between location based services (LBS) and online social networking (OSN). LBSN applications offer users the ability to look up the location of another “friend” remotely using a smart phone, desktop or other device, anytime and anywhere. Users invite their friends to participate in LBSN and there is a process of consent that follows. Friends have the ability to alter their privacy settings to allow their location to be monitored by another at …

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Realization Of Center Symmetry In Two Adjoint Flavor Large-N Yang-Mills, Simon Catterall, Richard Galvez, Mithat Unsal Jun 2010

Realization Of Center Symmetry In Two Adjoint Flavor Large-N Yang-Mills, Simon Catterall, Richard Galvez, Mithat Unsal

Physics - All Scholarship

We report on the results of numerical simulations of SU(N) lattice Yang Mills with two flavors of (light) Wilson fermion in the adjoint representation. We analytically and numerically address the question of center symmetry realization on lattices with \Gamma sites in each direction in the large-N limit. We show, by a weak coupling calculation that, for massless fermions, center symmetry realization is independent of \Gamma, and is unbroken. Then, we extend our result by conducting simulations at non zero mass and finite gauge coupling. Our results indicate that center symmetry is intact for a range of fermion mass in the …

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Cognitive Load Of Rating Scales, E. Isaac G. Sparling, Shilad Sen Jun 2010

Cognitive Load Of Rating Scales, E. Isaac G. Sparling, Shilad Sen

Mathematics, Statistics, and Computer Science Honors Projects

Why does Netflix.com use star ratings, Digg.com use up/down votes and Face- book use a “like” but not a “dislike” button? In this paper, we extend existing research on rating scales with findings from an experiment we ran to measure the cognitive load users experience while rating. In this paper, we analyze the cognitive load and time required by different rating scales. Our analysis draws upon 14,000 movie and product ratings we collected from 348 users through an online survey. In the survey, we measured the speed and cognitive load users ex- perience under four scales: unary (‘like it’), binary …

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Structured Decision-Making And Rapid Prototyping To Plan A Management Response To An Invasive Species, Sean M. Blomquist, Trisha D. Johnson, David R. Smith, Geoff P. Call, Brant N. Miller, W. Mark Thurman, Jamie E. Mcfadden, Mary J. Parkin, G. Scott Boomer Jun 2010

Structured Decision-Making And Rapid Prototyping To Plan A Management Response To An Invasive Species, Sean M. Blomquist, Trisha D. Johnson, David R. Smith, Geoff P. Call, Brant N. Miller, W. Mark Thurman, Jamie E. Mcfadden, Mary J. Parkin, G. Scott Boomer

School of Natural Resources: Faculty Publications

We developed components of a decision structure that could be used in an adaptive management framework for responding to invasion of hemlock woolly adelgid Adeleges tsugae on the Cumberland Plateau of northern Tennessee. Hemlock woolly adelgid, an invasive forest pest, was first detected in this area in 2007. We used a structured decision-making process to identify and refine the management problem, objectives, and alternative management actions, and to assess consequences and tradeoffs among selected management alternatives. We identified four fundamental objectives: 1) conserve the aquatic and terrestrial riparian conservation targets, 2) protect and preserve hemlock, 3) develop and maintain adequate …

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Structure And Oscillatory Multilayer Relaxation Of The Bismuth (100) Surface, J. Sun, J. Wang, J. Wells, Y. M. Koroteev, G. Bihlmayer, E. V. Chulkov, Ph Hofmann, Karsten Pohl Jun 2010

Structure And Oscillatory Multilayer Relaxation Of The Bismuth (100) Surface, J. Sun, J. Wang, J. Wells, Y. M. Koroteev, G. Bihlmayer, E. V. Chulkov, Ph Hofmann, Karsten Pohl

Physics & Astronomy

We present a combined experimental and theoretical study of the surface structure of single crystal Bi(100) via scanning tunneling microscopy (STM), low-energy electron diffraction intensity versus energy (LEED-IV) analysis and density functional theory (DFT). We find that the surface is unreconstructed and shows an unusually large oscillatory multilayer relaxation down to the sixth layer. This unexpected behavior will be explained by a novel mechanism related to the deeply penetrating electronic surface states. STM reveals wide (100) terraces, which are separated by two-layer high steps in which the shorter of the two interlayer spacings is terminating this surface, consistent with the …

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Where In The World? Demographic Patterns In Access Data, Mimi Recker, Beijie Xu, Sherry Hsi, Christine Garrard Jun 2010

Where In The World? Demographic Patterns In Access Data, Mimi Recker, Beijie Xu, Sherry Hsi, Christine Garrard

Instructional Technology and Learning Sciences Faculty Publications

Standard webmetrics tools record the IP address of users’ computers, thereby providing fodder for analyses of their geographical location, and for understanding the impact of e-learning and teaching. Here we describe how two web-based educational systems were engineered to collect geo-referenced data. This is followed by a description of joining these data with demographic and educational datasets for the United States, and mapping different datasets using geographic information system (GIS) techniques to visually display their relationships. Results from statistical analyses of these relationships that highlight areas of significance are given.

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