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2009

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Articles 3571 - 3600 of 7616

Full-Text Articles in Physical Sciences and Mathematics

The Maximum Rectilinear Crossing Number Of The N Dimensional Cube Graph, Matthew Alpert, Elie Feder, Heiko Harborth, Sheldon Klein Mar 2009

The Maximum Rectilinear Crossing Number Of The N Dimensional Cube Graph, Matthew Alpert, Elie Feder, Heiko Harborth, Sheldon Klein

Publications and Research

We find a.nd prove the maximum rectilinear crossing n1.1mber of the three-dimensional cube graph (Q3). We demonstrate a method of drawing then-cube graph, Qn., with many crossings, and thus find a lower bound for the maximum rectilinear crossing number of Qn. We conjecture that this bound is sharp. We also prove an upper bound for the maximum rectilinear crossing number of Qn.


Screen Complexity And User Design Preferences In Windows Applications, Tim Comber, John R. Maltby Mar 2009

Screen Complexity And User Design Preferences In Windows Applications, Tim Comber, John R. Maltby

Tim Comber

This paper evaluates the validity of a formal method for assessing the quality of screen layouts in graphical user interfaces. A technique developed by Bonsieppe for quantifying the layout complexity of a printed page has been applied to the opening screens in thirteen Microsoft Windows applications. Thirty subjects were asked to rank the same thirteen screens on the basis of "good" design. A significant negative correlation was found between the subjects’ rankings and the complexity ratings, indicating that users’ do not like “simple” screens. The reasons for this negative correlation are explored.


Extreme Physics Where Small And Big Things Meet, Young-Kee Kim Mar 2009

Extreme Physics Where Small And Big Things Meet, Young-Kee Kim

IMSA Great Minds Program ®

The profound discovery of Einstein a century ago, that particles can both be made from energy and disappear back into energy, inspires the experiments that provide our knowledge of the smallest building blocks of matter and the interactions between them. Experiments, done at enormous accelerators, have led to a consistent theory of the origins of our world up to a certain point. However, at an energy scale not far above what we can attain at existing accelerators, this picture is predicted to break down. Moreover, the theory of the very small is intimately connected to cosmology -- the ultimate cause …


The Importance Of Scale For Spatial-Confounding Bias And Precision Of Spatial Regression Estimators, Christopher J. Paciorek Mar 2009

The Importance Of Scale For Spatial-Confounding Bias And Precision Of Spatial Regression Estimators, Christopher J. Paciorek

Harvard University Biostatistics Working Paper Series

Increasingly, regression models are used when residuals are spatially correlated. Prominent examples include studies in environmental epidemiology to understand the chronic health effects of pollutants. I consider the effects of residual spatial structure on the bias and precision of regression coefficients, developing a simple framework in which to understand the key issues and derive informative analytic results. When the spatial residual is induced by an unmeasured confounder, regression models with spatial random effects and closely-related models such as kriging and penalized splines are biased, even when the residual variance components are known. Analytic and simulation results show how the bias …


Frequency Diversity For Improving Synthetic Aperture Radar Imaging, Jawad L. Farooq Mar 2009

Frequency Diversity For Improving Synthetic Aperture Radar Imaging, Jawad L. Farooq

Theses and Dissertations

In this work, a novel theoretical framework is presented for using recent advances in frequency diversity arrays (FDAs). Unlike a conventional array, the FDA simultaneously transmits a unique frequency from each element in the array. As a result, special time and space properties of the radiation pattern are exploited to improve cross-range resolution. The idealized FDA radiation pattern is compared with and validated against a full-wave electromagnetic solver, and it is shown that the conventional array is a special case of the FDA. A new signal model, based on the FDA, is used to simulate SAR imagery of ideal point …


Determining The Orbit Locations Of Turkish Airborne Early Warning And Control Aircraft Over The Turkish Air Space, Nebi Sarikaya Mar 2009

Determining The Orbit Locations Of Turkish Airborne Early Warning And Control Aircraft Over The Turkish Air Space, Nebi Sarikaya

Theses and Dissertations

The technology improvement affects the military needs of individual countries. The new doctrine of defense for many countries emphasizes detecting threats as far away as you can from your homeland. Today, the military uses both ground RADAR and Airborne Early Warning and Control (AEW&C) Aircraft. AEW&C aircraft has become vital to detect low altitude threats that a ground RADAR cannot detect because of obstacles on the earth. Turkey has ordered four AEW&C aircraft for her air defense system because of the lack of complete coverage by ground RADAR. This research provides optimal orbit locations that can be updated according to …


Linear Free Energy Relationship Correlations For Room Temperature Ionic Liquids: Revised Cation-Specific And Anion-Specific Equation Coefficients For Predictive Applications Covering A Much Larger Area Of Chemical Space, Laura M. Sprunger, Jennifer Gibbs, Amy Proctor, William E. Acree Jr., Michael H. Abraham, Yunjing Meng, Cong Yao, Jared L. Anderson Mar 2009

Linear Free Energy Relationship Correlations For Room Temperature Ionic Liquids: Revised Cation-Specific And Anion-Specific Equation Coefficients For Predictive Applications Covering A Much Larger Area Of Chemical Space, Laura M. Sprunger, Jennifer Gibbs, Amy Proctor, William E. Acree Jr., Michael H. Abraham, Yunjing Meng, Cong Yao, Jared L. Anderson

Jared L. Anderson

Previously reported ion-specific equation coefficients for both the Abraham general solvation model and Goss modified Abraham model are updated using recently measured activity coefficient, gas chromatographic retention factor, and solubility data for solutes dissolved in room temperature ionic liquids (RTILs). Reported for the first time are equation coefficients for 1-propyl-2,3-dimethylimidazolium cation, and octylsulfate and thiocyanate anions. In total nine sets of cation-specific and eight sets of anion-specific equation coefficients have been determined for each model. The derived correlations describe the 976 experimental gas-to-RTIL partition coefficients to within a standard deviation of 0.12 log units and the 955 experimental water-to-RTIL partitions …


An Adaptive Mesh Mpi Framework For Iterative C++ Programs, Karunamuni Charuka Silva Mar 2009

An Adaptive Mesh Mpi Framework For Iterative C++ Programs, Karunamuni Charuka Silva

Computer Science Theses

Computational Science and Engineering (CSE) applications often exhibit the pattern of adaptive mesh applications. Adaptive mesh algorithm starts with a coarse base-level grid structure covering entire computational domain. As the computation intensified, individual grid points are tagged for refinement. Such tagged grid points are dynamically overlayed with finer grid points. Similarly if the level of refinement in a cell is greater than required, all such regions are replaced with coarser grids. These refinements proceed recursively. We have developed an object-oriented framework enabling time-stepped adaptive mesh application developers to convert their sequential applications to MPI applications in few easy steps. We …


Uncooled Infrared Photon Detection Concepts And Devices, Viraj Vishwakantha Jayaweera Piyankarage Mar 2009

Uncooled Infrared Photon Detection Concepts And Devices, Viraj Vishwakantha Jayaweera Piyankarage

Physics and Astronomy Dissertations

This work describes infrared (IR) photon detector techniques based on novel semiconductor device concepts and detector designs. The aim of the investigation was to examine alternative IR detection concepts with a view to resolve some of the issues of existing IR detectors such as operating temperature and response range. Systems were fabricated to demonstrate the following IR detection concepts and determine detector parameters: (i) Near-infrared (NIR) detection based on dye-sensitization of nanostructured semiconductors, (ii) Displacement currents in semiconductor quantum dots (QDs) embedded dielectric media, (iii) Split-off band transitions in GaAs/AlGaAs heterojunction interfacial workfunction internal photoemission (HEIWIP) detectors. A far-infrared detector …


Social Networking Website Users And Privacy Concerns: A Mixed Methods Investigation, Stephanie J. Mills Mar 2009

Social Networking Website Users And Privacy Concerns: A Mixed Methods Investigation, Stephanie J. Mills

Theses and Dissertations

Social networking websites are the fastest growing entity on the Internet. Users of social networking websites post personal information and pictures on these websites. Privacy and social networking websites has been previously studied, however, since those studies were conducted the rules for those websites have changed dramatically. A mixed methods approach was used in this study to examine what privacy concerns users of social networking websites have, whether it’s regarding information on their accounts or the pictures they have posted. This study also considered if there were common personality traits present in people with those concerns. A comparison of user …


Mammaglobin As A Potential Molecular Target For Breast Cancer Drug Delivery, Lian Zuo, Ly Li, Qian Wang, Timothy P. Fleming, Shaojin You Mar 2009

Mammaglobin As A Potential Molecular Target For Breast Cancer Drug Delivery, Lian Zuo, Ly Li, Qian Wang, Timothy P. Fleming, Shaojin You

Faculty Publications

Background Mammaglobin (MAM) has been used as a specific molecular marker for breast cancer diagnosis. Recently, several groups of researchers proposed a number of therapeutic strategies targeting this molecule. Some of the strategies are based upon an essential but not demonstrated hypothesis - mammaglobin is associated with the surface of breast cancer cells, which strongly disputes the therapeutic strategies. Results We conducted a computer-based predictive analysis and identified a small fragment at the N-end of MAM as a potential transmembrane domain. We provided several evidences to demonstrate the presence of the membrane-associated MAM. We isolated the membrane protein components from …


Studies On Construction And List Decoding Of Codes On Some Towers Of Function Fields., M. Prem Laxman Das Dr. Mar 2009

Studies On Construction And List Decoding Of Codes On Some Towers Of Function Fields., M. Prem Laxman Das Dr.

Doctoral Theses

In everyday life, there arise many situations where two parties, sender and receiver, need to communicate. The channel through which they communicate is assumed to be binary symmetric, that is, it changes 0 to 1 and vice versa with equal probability. At the receiver’s end, the sent message has to be recovered from the corrupted received word using some reasonable mechanism. This real life problem has attracted a lot of research in the past few decades. A solution to this problem is obtained by adding redundancy in a systematic manner to the message to construct a codeword. The collection of …


Exploitation Of Geographic Information Systems For Vehicular Destination Prediction, Richard T. Muster Mar 2009

Exploitation Of Geographic Information Systems For Vehicular Destination Prediction, Richard T. Muster

Theses and Dissertations

Much of the recent successes in the Iraqi theater have been achieved with the aid of technology so advanced that celebrated journalist Bob Woodward recently compared it to the Manhattan Project of WWII. Intelligence, Surveillance, and Reconnaissance (ISR) platforms have emerged as the rising star of Air Force operational capabilities as they are enablers in the quest to track and disrupt terrorist and insurgent forces. This thesis argues that ISR systems have been severely under-exploited. The proposals herein seek to improve the machine-human interface of current ISR systems such that a predictive battle-space awareness may be achieved, leading to shorter …


Ringworld: Travellers' Tales From Saturn, Shane L. Larson Mar 2009

Ringworld: Travellers' Tales From Saturn, Shane L. Larson

Public Talks

No abstract provided.


Periodic And Dynamic 3-D Gold Nanoparticle− Dna Network Structures For Surface-Enhanced Raman Spectroscopy-Based Quantification, Kyuwan Lee Mar 2009

Periodic And Dynamic 3-D Gold Nanoparticle− Dna Network Structures For Surface-Enhanced Raman Spectroscopy-Based Quantification, Kyuwan Lee

Kyuwan Lee

The enhancement factor of gold nanoparticles linked by DNA in a three-dimensional (3-D) network structure was evaluated as 1.12 × 107 and shown to be greater than a two-dimensional (2-D) array by a factor of 10, possibly due to the dimensional expansion of resonance and periodicity of the so formed structures. Uniform and higher level of enhancement was possible from these DNA linked gold nanoparticle networks because of the matching of the resonant condition and the excitation wavelength (785 nm) to enable dynamic quantification of analytes by surface-enhanced Raman spectroscopy (SERS). The structure was first validated by obtaining a SERS …


Functionalization, Characterization, And Applications Of Diamond Particles, Modification Of Planar Silicon, And Chemoetrics Analysis Of Ms Data, Li Yang Mar 2009

Functionalization, Characterization, And Applications Of Diamond Particles, Modification Of Planar Silicon, And Chemoetrics Analysis Of Ms Data, Li Yang

Theses and Dissertations

In spite of the stablility (lack of reactivity) of diamond powder, I have developed a method for tethering alkyl chains and polymers to deuterium/hydrogen-terminated diamond. One method is through ether linkages via thermolysis of di-tert-amyl peroxide (DTAP). This reaction with DTAP has also been applied to grow polymers on the diamond surface. The other method is atom transfer radical polymerization (ATRP), which was applied to grow polystyrene at the surface of diamond. Both polystyrene-modified diamond and sulfonated polystyrene-modified diamond can be prepared by either method, and can be used for solid phase extraction. Diamond stationary phases are stable under basic …


Bit-Error-Rate-Minimizing Channel Shortening Using Post-Feq Diversity Combining And A Genetic Algorithm, Gokhan Altin Mar 2009

Bit-Error-Rate-Minimizing Channel Shortening Using Post-Feq Diversity Combining And A Genetic Algorithm, Gokhan Altin

Theses and Dissertations

In advanced wireline or wireless communication systems, i.e., DSL, IEEE 802.11a/g, HIPERLAN/2, etc., a cyclic prefix which is proportional to the channel impulse response is needed to append a multicarrier modulation (MCM) frame for operating the MCM accurately. This prefix is used to combat inter symbol interference (ISI). In some cases, the channel impulse response can be longer than the cyclic prefix (CP). One of the most useful techniques to mitigate this problem is reuse of a Channel Shortening Equalizer (CSE) as a linear preprocessor before the MCM receiver in order to shorten the effective channel length. Channel shortening filter …


All-Sky Ligo Search For Periodic Gravitational Waves In The Early Fifth-Science-Run Data, B. P. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. S. Amin, S. B. Anderson, W. G. Anderson, M. A. Arain, M. Araya, H. Armandula, P. Armor, Y. Aso, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, L. Barsotti, M. A. Barton, I. Bartos, R. Bassiri, M. Bastarrika, Tiffany Z. Summerscales Mar 2009

All-Sky Ligo Search For Periodic Gravitational Waves In The Early Fifth-Science-Run Data, B. P. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. S. Amin, S. B. Anderson, W. G. Anderson, M. A. Arain, M. Araya, H. Armandula, P. Armor, Y. Aso, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, P. Baker, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, L. Barsotti, M. A. Barton, I. Bartos, R. Bassiri, M. Bastarrika, Tiffany Z. Summerscales

Faculty Publications

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100Hz and with the frequency's time derivative in the range -5×10-9-0Hzs-1. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10-24 are obtained over a 200-Hz band, and the sensitivity …


Hearing Voices In The Dark: Probing The Gravitational Wave Cosmos With Lisa, Shane L. Larson Mar 2009

Hearing Voices In The Dark: Probing The Gravitational Wave Cosmos With Lisa, Shane L. Larson

Colloquia and Seminars

No abstract provided.


Combined Visible And Infrared Video For Use In Wilderness Search And Rescue, Nathan D. Rasmussen Mar 2009

Combined Visible And Infrared Video For Use In Wilderness Search And Rescue, Nathan D. Rasmussen

Theses and Dissertations

Mini Unmanned Aerial Vehicles (mUAVs) have the potential to be a great asset to Wilderness Search and Rescue groups by providing a bird's eye view of the search area. These vehicles can carry a variety of sensors to better understand the world below. This paper proposes using both Infrared (IR) and Visible Spectrum cameras on a mUAV for Wilderness Search and Rescue. It details a method for combining the color and heat information from these two cameras into a single fused display to reduce needed screen space for remote field use. To align the video frames for fusion, a method …


The First Attachment And Post-Functionalization Of Polybutadiene And Thio-Click Functionalized Polybutadiene On H-Terminated Si(111), Todd Devere Wickard Mar 2009

The First Attachment And Post-Functionalization Of Polybutadiene And Thio-Click Functionalized Polybutadiene On H-Terminated Si(111), Todd Devere Wickard

Theses and Dissertations

I report the attachment of polymers with pendant vinyl groups to hydrogen-terminated silicon(111) (Si(111)-H) under mild conditions. 1,2-addition polybutadiene (Mw 3200-3500) was attached to Si(111)-H at room temperature with visible light. I also report the partial functionalization, in solution, of 1,2-addition polybutadiene with various thiols using thiol-click chemistry. These compounds bind to Si(111)-H via visible light activation. The partially functionalized polybutadienes allow further functionalization at the surface through unreacted carbon-carbon double bonds. Surfaces were characterized with contact angle goniometry, spectroscopic ellipsometry, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and atomic force microscopy (AFM).


Smoking Enhances Risk For New External Genital Warts In Men, Dorothy J. Wiley, David Elashoff, Emmanuel V. Masongsong, Diane M. Harper Mar 2009

Smoking Enhances Risk For New External Genital Warts In Men, Dorothy J. Wiley, David Elashoff, Emmanuel V. Masongsong, Diane M. Harper

Dartmouth Scholarship

Repeat episodes of HPV-related external genital warts reflect recurring or new infections. No study before has been sufficiently powered to delineate how tobacco use, prior history of EGWs and HIV infection affect the risk for new EGWs. Behavioral, laboratory and examination data for 2,835 Multicenter AIDS Cohort Study participants examined at 21,519 semi-annual visits were evaluated. Fourteen percent (391/2835) of men reported or were diagnosed with EGWs at 3% (675/21,519) of study visits. Multivariate analyses showed smoking, prior episodes of EGWs, HIV infection and CD4+ T-lymphocyte count among the infected, each differentially influenced the risk for new EGWs.


Lake Whatcom Monitoring Project 2007/2008 Report, Robin A. Matthews, Michael Hilles, Joan Vandersypen, Robert J. Mitchell, Geoffrey B. Matthews Mar 2009

Lake Whatcom Monitoring Project 2007/2008 Report, Robin A. Matthews, Michael Hilles, Joan Vandersypen, Robert J. Mitchell, Geoffrey B. Matthews

Lake Whatcom Annual Reports

This report is part of an on-going series of annual reports and special project reports that document the Lake Whatcom monitoring program. This work is conducted by the Institute for Watershed Studies and other departments at Western Washington University.

The major objective of this program is to provide long-term baseline water quality monitoring in Lake Whatcom and selected tributaries. Each section contains brief explanations about the water quality data, along with discussions of patterns observed in Lake Whatcom.


Dynamic Network Formation Using Ant Colony Optimization, Steven C. Oimoen Mar 2009

Dynamic Network Formation Using Ant Colony Optimization, Steven C. Oimoen

Theses and Dissertations

Military and industry are moving toward every device being network enabled and connected for reliable availability of communication and information. To make this type of system a reality, the devices must be capable of forming a network topology on their own in a dynamic environment to ensure that the correct information reaches a desired location and on-time. This research presents three contributions for solving highly dynamic (i.e. drastic change within the network) Multi-commodity Capacitated Network Design Problems (MCNDPs) resulting in a distributed multi-agent network design algorithm. The first contribution incorporates an Ant Colony Optimization (ACO) algorithm Ant Colony System (ACS) …


A Framework For Analyzing Biometric Template Aging And Renewal Prediction, John W. Carls Mar 2009

A Framework For Analyzing Biometric Template Aging And Renewal Prediction, John W. Carls

Theses and Dissertations

Biometric technology and systems are modernizing identity capabilities. With maturing biometrics in full, rapid development, a higher accuracy of identity verification is required. An improvement to the security of biometric-based verification systems is provided through higher accuracy; ultimately reducing fraud, theft, and loss of resources from unauthorized personnel. With trivial biometric systems, a higher acceptance threshold to obtain higher accuracy rates increase false rejection rates and user unacceptability. However, maintaining the higher accuracy rate enhances the security of the system. An area of biometrics with a paucity of research is template aging and renewal prediction, specifically in regards to facial …


Forecasting Usaf Jp-8 Fuel Needs, Omer Saglam Mar 2009

Forecasting Usaf Jp-8 Fuel Needs, Omer Saglam

Theses and Dissertations

Oil is still one of the strategic energy resources for both the U.S. and the USAF today. Accurate oil prediction is important for the U.S. in order to improve the national strategy and the related budget concerns. Today, the U.S. is roughly importing 58% of its petroleum products. Moreover, in Fiscal Year (FY) 2007 the USAF total energy costs exceeded $6.9 billion. Aviation fuel accounted for approximately 81% of the total AF energy costs. Fluctuations in oil prices have huge impacts on the USAF’s JP-8 budgetary calculations. In order to handle this problem, the need for accurate forecasts arises. In …


The Economic Impact Of A Radiological Dispersal Device (Rde), Michael T. Lebrun Mar 2009

The Economic Impact Of A Radiological Dispersal Device (Rde), Michael T. Lebrun

Theses and Dissertations

While it will not cause the devastation of a nuclear weapon, the radiological dispersal event (RDE) is particularly dangerous in that it has the potential to cause major economic disruptions. The purpose of this research was to develop a generalized methodology that can be used to assess economic impacts, resulting from a (RDE), occurring in any location and across any industry. Currently, there is no universal approach for measuring the costs or economic impacts on businesses, or a common framework for conducting an economic impact for a RDE. The objective of this research was to aid in the RDE response …


Uberveillance: Microchipping People And The Assault On Privacy, M. G. Michael, Katina Michael Mar 2009

Uberveillance: Microchipping People And The Assault On Privacy, M. G. Michael, Katina Michael

Professor Katina Michael

Uberveillance is above and beyond, an exaggerated, and omnipresent 24/7 electronic surveillance. It is a surveillance that is not only always on but always with you. It is ever-present because the technology that facilitates it, in its ultimate implementation, is embedded within the human body. The inherent problem with this kind of bodily pervasive surveillance is that omnipresence will not always equate with omniscience. Infallibility and ambient context will be for the greater part absent. For as Marcus Wigan has pithily put it, “context is all.” Hence the real concern for misinformation, misinterpretation, and information manipulation of citizens’ data.


Size And Geometry Dependent Protein-Nanoparticle Self-Assembly, M De, Or Miranda, S Rana, Vm Rotello Mar 2009

Size And Geometry Dependent Protein-Nanoparticle Self-Assembly, M De, Or Miranda, S Rana, Vm Rotello

Vincent Rotello

Fundamentally different assembly motifs are observed when proteins of different sizes are complexed with monolayer-protected nanoparticles.


Supporting Real-World Activities In Database Management Systems, Mohamed Eltabakh, Walid G. Aref, Ahmed K. Elmagarmid, Yasin Laura-Silva, Mourad Ouzzani Mar 2009

Supporting Real-World Activities In Database Management Systems, Mohamed Eltabakh, Walid G. Aref, Ahmed K. Elmagarmid, Yasin Laura-Silva, Mourad Ouzzani

Department of Computer Science Technical Reports

No abstract provided.