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2006

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Articles 2881 - 2910 of 5872

Full-Text Articles in Physical Sciences and Mathematics

Discrete Shells Origami, Rob Burgoon, Zoë J. Wood, Eitan Grinspun Mar 2006

Discrete Shells Origami, Rob Burgoon, Zoë J. Wood, Eitan Grinspun

Computer Science and Software Engineering

We introduce a way of simulating the creation of simple Origami (paper folding). The Origami is created in a thin shell simulation that realistically models the behavior and physical properties of paper. We demonstrate how to fold and crease the simulated paper wherever the user desires. This work employs cutting-edge advances in the field of discrete shell modeling to meet the challenge of simulating Origami. We found that the discrete shell model is capable of creating simple Origami that does not involve paper to paper collisions. For more advanced origami, however, some kind of collision detection and resolution scheme is …


A Selective Approach To Bandwidth Overbooking, Feng Huang Mar 2006

A Selective Approach To Bandwidth Overbooking, Feng Huang

Theses and Dissertations

Overbooking is a technique used by network providers to increase bandwidth utilization. If the overbooking factor is chosen appropriately, additional virtual circuits can be admitted without degrading quality of service for existing customers. Most existing implementations use a single factor to accept a linear fraction of traffic requests. High values of this factor may cause the degradation of quality of service whereas low overbooking factors will result in underutilization of bandwidth. Network providers often select overbooking factors based only on aggregate average virtual circuit utilization. This paper proposes a selective overbooking scheme based on trunk size and usage profile. Experiments …


The Structure Of Flux Transfer Events Recovered From Cluster Data, H Hasegawa, B U. Ö Sonnerup, C J. Owen, B Klecker, G Paschmann, A Balogh, H Re`Me Mar 2006

The Structure Of Flux Transfer Events Recovered From Cluster Data, H Hasegawa, B U. Ö Sonnerup, C J. Owen, B Klecker, G Paschmann, A Balogh, H Re`Me

Dartmouth Scholarship

The structure and formation mechanism of a to- tal of five Flux Transfer Events (FTEs), encountered on the equatorward side of the northern cusp by the Cluster space- craft, with separation of ∼5000 km, are studied by apply- ing the Grad-Shafranov (GS) reconstruction technique to the events. The technique generates a magnetic field/plasma map of the FTE cross section, using combined magnetic field and plasma data from all four spacecraft, under the assump- tion that the structure is two-dimensional (2-D) and time- independent. The reconstructed FTEs consist of one or more magnetic flux ropes embedded in the magnetopause, suggest- ing …


Comparative Investigations Of Equatorial Electrodynamics And Low-To-Mid Latitude Coupling Of The Thermosphere-Ionosphere System, M J. Colerico, M Mendillo, C G. Fesen, J Meriwether Mar 2006

Comparative Investigations Of Equatorial Electrodynamics And Low-To-Mid Latitude Coupling Of The Thermosphere-Ionosphere System, M J. Colerico, M Mendillo, C G. Fesen, J Meriwether

Dartmouth Scholarship

The thermospheric midnight temperature maxi-

mum (MTM) is a highly variable, but persistent, large scale

neutral temperature enhancement which occurs at low lati-

tudes. Its occurrence can impact many fundamental upper

atmospheric parameters such as pressure, density, neutral

winds, neutral density, and F-region plasma. Although the

MTM has been the focus of several investigations employ-

ing various instrumentation including photometers, satellites,

and Fabry-Perot interferometers, limited knowledge exists

regarding the latitude extent of its influence on the upper at-

mosphere. This is largely due to observational limitations

which confined the collective geographic range to latitudes

within ±23◦. This paper investigates the …


Constancy In Integrated Cisplatin Plasma Concentrations Among Pediatric Patients, Jerry Goodisman, Abdul-Kader Souid Mar 2006

Constancy In Integrated Cisplatin Plasma Concentrations Among Pediatric Patients, Jerry Goodisman, Abdul-Kader Souid

Chemistry - All Scholarship

The authors report on the variability in the integrated quantity of free (unbound) plasma cisplatin (area under curve of plasma concentration versus time, AUC). The AUC was measured in 19 patients receiving cisplatin doses proportional to body surface areas (BSA), 30mg/m2 over 1 hour. The relative standard deviation (RSD, population standard deviation divided by mean value) for the maximum free plasma cisplatin concentration (Cmax, μM) was 0.338; for the half-life (t½, minute), 0.210; and for the AUC (μM minute), 0.320. Thus, BSA-based dosing gave significant variability in the AUC. We attempted to use (weight)a(height)b, seeking values of a and b …


Seasonal Variation Of Diurnal Perturbations In Mesopause Regiontemperature, Zonal, And Meridional Winds Above Fort Collins, Colorado (40.6°N, 105°), Tao Yuan, C. Y. She, M. E. Hagan, B. P. William, T. Li, K. Arnold, T. D. Kawahara, P. E. Acott, J. D. Vance, D. A. Krueger, R. G. Roble Mar 2006

Seasonal Variation Of Diurnal Perturbations In Mesopause Regiontemperature, Zonal, And Meridional Winds Above Fort Collins, Colorado (40.6°N, 105°), Tao Yuan, C. Y. She, M. E. Hagan, B. P. William, T. Li, K. Arnold, T. D. Kawahara, P. E. Acott, J. D. Vance, D. A. Krueger, R. G. Roble

All Physics Faculty Publications

On the basis of lidar observations from May 2002 through April 2003, covering both day and night, we performed a harmonic analysis to extract the diurnal perturbations in mesopause region temperature, zonal and meridional winds over Fort Collins, Colorado (40.6°N, 105°W), binned every 2 months. The results were compared to predictions of the 2000 and 2002 versions of Global-Scale Wave Model (GSWM00 and GSWM02). The diurnal tidal period oscillations showed a mixture of propagating and evanescent (trapped) modes, but the propagating modes dominated for most of the year. The agreement in temperature diurnal phases between observation and GSWM prediction is …


Learning Real-World Problems By Finding Correlated Basis Functions, Adam C. Drake Mar 2006

Learning Real-World Problems By Finding Correlated Basis Functions, Adam C. Drake

Theses and Dissertations

Learning algorithms based on the Fourier transform attempt to learn functions by approximating the largest coefficients of their Fourier representations. Nearly all previous work in Fourier-based learning has been in the theoretical realm, where properties of the transform have made it possible to prove many interesting learnability results. The real-world usefulness of Fourier-based methods, however, has not been thoroughly explored. This thesis explores methods for the practical application of Fourier-based learning. The primary contribution of this thesis is a new search algorithm for finding the largest coefficients of a function's Fourier representation. Although the search space is exponentially large, empirical …


User Datagram Protocol With Congestion Control, Spencer L. Cox Mar 2006

User Datagram Protocol With Congestion Control, Spencer L. Cox

Theses and Dissertations

Communication through the Internet is one of the dominant methods of exchanging information. Whether at an individual or large corporate level the Internet has become essential to gathering and disseminating information. TCP and UDP are the transport layer protocols responsible for transit of nearly all Internet communications. Due to the growth of real-time audio and video applications, UDP is being used more frequently as a transport protocol. As UDP traffic increases potential problems arise. Unlike TCP, UDP has no mechanism for congestion control leading to wasted bandwidth and poor performance for other competing protocols. This thesis defines a congestion control …


General Classification And Analysis Of Neutron Β-Decay Experiments, Vladimir Gudkov, G. L. Greene, J. R. Calarco Mar 2006

General Classification And Analysis Of Neutron Β-Decay Experiments, Vladimir Gudkov, G. L. Greene, J. R. Calarco

Faculty Publications

A general analysis of the sensitivities of neutron β-decay experiments to manifestations of possible interaction beyond the standard model is carried out. In a consistent fashion, we take into account all known radiative and recoil corrections arising in the standard model. This provides a description of angular correlations in neutron decay in terms of one parameter, which is accurate to the level of ~10-5. Based on this general expression, we present an analysis of the sensitivities to new physics for selected neutron decay experiments. We emphasize that the usual parametrization of experiments in terms of the tree-level coefficients …


Ordered Pattern Matching: Towards Full-Text Retrieval, Wing-Kail Hon, Rahul Shah, Jeffrey S. Vitter Mar 2006

Ordered Pattern Matching: Towards Full-Text Retrieval, Wing-Kail Hon, Rahul Shah, Jeffrey S. Vitter

Department of Computer Science Technical Reports

No abstract provided.


Efficient Large Scale Acquisition Of Building Interiors, Gleb Bahmutov, Voicu Popescu, Mihai Mudure Mar 2006

Efficient Large Scale Acquisition Of Building Interiors, Gleb Bahmutov, Voicu Popescu, Mihai Mudure

Department of Computer Science Technical Reports

No abstract provided.


Magnetic Materials (Appendix To Advanced Magnetic Nanostructures [2006]), David J. Sellmyer, Ralph Skomski Mar 2006

Magnetic Materials (Appendix To Advanced Magnetic Nanostructures [2006]), David J. Sellmyer, Ralph Skomski

Ralph Skomski Publications

The behavior of magnetic nanostructures reflects both nanoscale features, such as particle size and geometry, and the intrinsic properties of the magnetic substances. For example, the magnetization reversal in nanodots crucially depends on the anisotropy of the dot material. Furthermore, nanostructures are often used as bulk materials, so that their extrinsic properties must be evaluated from the point of view of bulk materials. This appendix summarizes the characteristics of some important classes of magnetic materials and provides exemplary data.


Electrolytic Deposition Of Coatings For Prosthetic Metals And Alloys, Jody G. Redepenning Mar 2006

Electrolytic Deposition Of Coatings For Prosthetic Metals And Alloys, Jody G. Redepenning

Chemistry Department: Faculty Publications

An article coated with an electrolytically deposited biocompatible composite layer useful as an internal prosthetic device is disclosed. The bio-compatible composite coating that is electrolytically deposited onto the article comprises hydroxyapatite and chitosan. The introduction of chitosan into the crystal matrix of brushite/hydroxyapatite significantly improves the adhesive and chemical and mechanical stability properties of the coating.
United States Patent Number 7,014,749 B2


Red Rock Desert Learning Center Core Group Meeting: March 21, 2006, Red Rock Desert Learning Center Mar 2006

Red Rock Desert Learning Center Core Group Meeting: March 21, 2006, Red Rock Desert Learning Center

Reports (RRLC)

  1. Introductions & Announcements (5 min.)
  2. Approval of Minutes from January 17, 2006 Meeting (5 min.)
  3. Update on Project Schedule – Michael Reiland (10 min.)
    A. Utilities
    B. Water Line
    C. Operator RFP
    D. NEPA
  4. Report on Value Analysis Workshops – Michael Reiland / Line & Space
    (10 min.)
    A. Cost Estimates/Inflation
  5. Curriculum Update – Jeanne Klockow (10 min.)
  6. Standing Reports (10 min.)
    A. Line and Space – Les Wallach
    B. BLM Capital Improvements – Michael Reiland
  7. Committee Reports (5 min.)
    A. Building Committee
    B. Design Oversight
    C. Educational Programs
    D. Fund-raising and Partnerships
    E. NEPA
    F. Operations
    G. Other Uses …


Browser-Based Trust Negotiation, Cameron Morris Mar 2006

Browser-Based Trust Negotiation, Cameron Morris

Theses and Dissertations

Trust negotiation allows two parties on the Internet to establish trust in each other according to the digital credentials thateach other possesses. Traditionally, trust negotiation uses certificates as digital credentials. However, certificates make trust negotiation difficult to use since people rarely have certificates available to them, and they must physically possess and secure all needed certificates in order to negotiate. To avoid these problems, this thesis proposes that credential authorities negotiate on behalf of the user. This thesis defines BrowserBased Trust Negotiation (BBTN) as a method for negotiating with credential authorities using the Secure Assertion Markup Language (SAML).


Science Translation For Non-Point Source Pollution Control – A Cultural Models Approach With Municipal Officials: A Final Report Submitted To The Noaa/Unh Cooperative Institute For Coastal And Estuarine Environmental Technology (Ciceet), Christine Baumann Feurt Mar 2006

Science Translation For Non-Point Source Pollution Control – A Cultural Models Approach With Municipal Officials: A Final Report Submitted To The Noaa/Unh Cooperative Institute For Coastal And Estuarine Environmental Technology (Ciceet), Christine Baumann Feurt

Environmental Studies Faculty Publications

No abstract provided.


Detecting Pulsatile Hormone Secretion Events: A Bayesian Approach, Tim Johnson Mar 2006

Detecting Pulsatile Hormone Secretion Events: A Bayesian Approach, Tim Johnson

The University of Michigan Department of Biostatistics Working Paper Series

Many challenges arise in the analysis of pulsatile, or episodic, hormone concentration time series data. Among these challenges is the determination of the number and location of pulsatile events and the discrimination of events from noise. Analyses of these data are typically performed in two stages. In the first stage, the number and approximate location of the pulses are determined. In the second stage, a model (typically a deconvolution model) is fit to the data conditional on the number of pulses. Any error made in the first stage is carried over to the second stage. Furthermore, current methods, except two, …


Encryption Of Computer Peripheral Devices, Kelly Robert Norman Mar 2006

Encryption Of Computer Peripheral Devices, Kelly Robert Norman

Theses and Dissertations

Computer peripherals, such as keyboards, scanners, printers, cameras, and Personal Data Assistants (PDAs) typically communicate with a host PC via an unencrypted protocol, leaving them vulnerable to eavesdropping techniques, such as keyloggers. An encryption system was developed that is simple enough to be used in peripherals that do not have large amounts of processing power and memory. A software driver loaded in the operating system of the host computer communicates with a simple 8-bit microcontroller in the peripheral device. The driver handles key generation, key exchange, and provides decrypted data to the operating system. A key exchange protocol allows the …


Semiparametric Analysis For Correlated Recurrent And Terminal Events, Yining Ye, Jack Kalbfleisch, Doug E. Schaubel Mar 2006

Semiparametric Analysis For Correlated Recurrent And Terminal Events, Yining Ye, Jack Kalbfleisch, Doug E. Schaubel

The University of Michigan Department of Biostatistics Working Paper Series

In clinical and observational studies, recurrent event data (e.g. hospitalization) with a terminal event (e.g. death) are often encountered. In many instances, the terminal event is strongly correlated with the recurrent event process. In this article, we propose a semiparametric method to jointly model the recurrent and terminal event processes. The dependence is modeled by a shared gamma frailty that is included in both the recurrent event rate and terminal event hazard function. Marginal models are used to estimate the regression effects on the terminal and recurrent event processes and a Poisson model is used to estimate the dispersion of …


Gray Wolf Populations In The United States, 2006 Mar 2006

Gray Wolf Populations In The United States, 2006

Rocky Mountain Wolf Recovery: Annual Reports

Gray Wolf Populations


Secondary Terms In The Number Of Vanishings Of Quadratic Twists Of Elliptic Curve L-Functions, J. Brian Conrey, Atul Pocharel, Michael O. Rubinstein, Mark Watkins Mar 2006

Secondary Terms In The Number Of Vanishings Of Quadratic Twists Of Elliptic Curve L-Functions, J. Brian Conrey, Atul Pocharel, Michael O. Rubinstein, Mark Watkins

Mathematics - All Scholarship

We examine the number of vanishings of quadratic twists of the L-function associated to an elliptic curve. Applying a conjecture for the full asymptotics of the moments of critical L-values we obtain a conjecture for the first two terms in the ratio of the number of vanishings of twists sorted according to arithmetic progressions.


Development Of An Unbiased Statistical Method For The Analysis Of Unigenic Evolution, Colleen D. Behrsin, Chris J. Brandl, David W. Litchfield, Brian H. Shilton, Lindi M. Wahl Mar 2006

Development Of An Unbiased Statistical Method For The Analysis Of Unigenic Evolution, Colleen D. Behrsin, Chris J. Brandl, David W. Litchfield, Brian H. Shilton, Lindi M. Wahl

Biochemistry Publications

Background: Unigenic evolution is a powerful genetic strategy involving random mutagenesis of a single gene product to delineate functionally important domains of a protein. This method involves selection of variants of the protein which retain function, followed by statistical analysis comparing expected and observed mutation frequencies of each residue. Resultant mutability indices for each residue are averaged across a specified window of codons to identify hypomutable regions of the protein. As originally described, the effect of changes to the length of this averaging window was not fully eludicated. In addition, it was unclear when sufficient functional variants had been examined …


Adjusting For Covariate Effects On Classification Accuracy Using The Covariate-Adjusted Roc Curve, Holly Janes, Margaret S. Pepe Mar 2006

Adjusting For Covariate Effects On Classification Accuracy Using The Covariate-Adjusted Roc Curve, Holly Janes, Margaret S. Pepe

UW Biostatistics Working Paper Series

Recent scientific and technological innovations have produced an abundance of potential markers which are being investigated for their use in disease screen- ing and diagnosis. In evaluating these markers, it is often necessary to account for covariates which are associated with the marker of interest. These covariates may include subject characteristics, expertise of the test operator, test proce- dures, or aspects of specimen handling. In this paper, we propose the AROC, a covariate-adjusted measure of the classification accuracy. The AROC is the common covariate-specific ROC curve, when the covariate does not affect dis- crimination, and a weighted average of covariate-specific …


The Structure Of Β-Carbonic Anhydrase From The Carboxysomal Shell Reveals A Distinct Subclass With One Active Site For The Price Of Two, Michael R. Sawaya, Gordon C. Cannon, Sabine Heinhorst, Shiho Tanaka, Eric B. Williams, Todd O. Yeates, Cheryl A. Kerfeld Mar 2006

The Structure Of Β-Carbonic Anhydrase From The Carboxysomal Shell Reveals A Distinct Subclass With One Active Site For The Price Of Two, Michael R. Sawaya, Gordon C. Cannon, Sabine Heinhorst, Shiho Tanaka, Eric B. Williams, Todd O. Yeates, Cheryl A. Kerfeld

Faculty Publications

CsoSCA (formerly CsoS3) is a bacterial carbonic anhydrase localized in the shell of a cellular microcompartment called the carboxysome, where it converts HCO-3 to CO2 for use in carbon fixation by ribulose-bisphosphate carboxylase/oxygenase (RuBisCO). CsoSCA lacks significant sequence similarity to any of the four known classes of carbonic anhydrase (α, β, γ, or δ), and so it was initially classified as belonging to a new class, ϵ. The crystal structure of CsoSCA from Halothiobacillus neapolitanus reveals that it is actually a representative member of a new subclass of β-carbonic anhydrases, distinguished by a lack of active site …


Measurement Of The Dipion Mass Spectrum In X(3872) → J/Ψπ+Π- Decays, A. Abulencia, Kenneth A. Bloom, Cdf Collaboration Mar 2006

Measurement Of The Dipion Mass Spectrum In X(3872) → J/Ψπ+Π- Decays, A. Abulencia, Kenneth A. Bloom, Cdf Collaboration

Kenneth Bloom Publications

We measure the dipion mass spectrum in X(3872) → J/ψ π + π - decays using 360 pb-1 of p̅p collisions at √s = 1.96 TeV collected with the CDF II detector. The spectrum is fit with predictions for odd C-parity (3S1, 1P1, and 3DJ) charmonia decaying to J/ π + π -, as well as even C-parity states in which the pions are from ρ0 decay. The latter case also encompasses exotic interpretations, such as a D0*0 molecule. …


Factors Impacting Key Management Effectiveness In Secured Wireless Networks, Yongjoo Shin Mar 2006

Factors Impacting Key Management Effectiveness In Secured Wireless Networks, Yongjoo Shin

Theses and Dissertations

The use of a Public Key Infrastructure (PKI) offers a cryptographic solution that can overcome many, but not all, of the MANET security problems. One of the most critical aspects of a PKI system is how well it implements Key Management. Key Management deals with key generation, key storage, key distribution, key updating, key revocation, and certificate service in accordance with security policies over the lifecycle of the cryptography. The approach supported by traditional PKI works well in fixed wired networks, but it may not appropriate for MANET due to the lack of fixed infrastructure to support the PKI. This …


A Multi-Site Analysis Of Random Error In Tower-Based Measurements Of Carbon And Energy Fluxes, Andrew D. Richardson, David Y. Hollinger, George C. Burba, Kenneth J. Davis, Lawrence B. Flanagan, Gabriel G. Katul, J. William Munger, Daniel M. Ricciuto, Paul C. Stoy, Andrew E. Suyker, Shashi Verma, Steven C. Wofsy Mar 2006

A Multi-Site Analysis Of Random Error In Tower-Based Measurements Of Carbon And Energy Fluxes, Andrew D. Richardson, David Y. Hollinger, George C. Burba, Kenneth J. Davis, Lawrence B. Flanagan, Gabriel G. Katul, J. William Munger, Daniel M. Ricciuto, Paul C. Stoy, Andrew E. Suyker, Shashi Verma, Steven C. Wofsy

School of Natural Resources: Faculty Publications

Measured surface-atmosphere fluxes of energy (sensible heat, H, and latent heat, LE) and CO2 (FCO2) represent the ‘‘true’’ flux plus or minus potential random and systematic measurement errors. Here, we use data from seven sites in the AmeriFlux network, including five forested sites (two of which include “tall tower” instrumentation), one grassland site, and one agricultural site, to conduct a cross-site analysis of random flux error. Quantification of this uncertainty is a prerequisite to model-data synthesis (data assimilation) and for defining confidence intervals on annual sums of net ecosystem exchange or making statistically valid comparisons between …


Censored Data Regression In High-Dimension And Low-Sample Size Settings For Genomic Applications, Hongzhe Li Mar 2006

Censored Data Regression In High-Dimension And Low-Sample Size Settings For Genomic Applications, Hongzhe Li

UPenn Biostatistics Working Papers

New high-throughput technologies are generating various types of high-dimensional genomic and proteomic data and meta-data (e.g., networks and pathways) in order to obtain a systems-level understanding of various complex diseases such as human cancers and cardiovascular diseases. As the amount and complexity of the data increase and as the questions being addressed become more sophisticated, we face the great challenge of how to model such data in order to draw valid statistical and biological conclusions. One important problem in genomic research is to relate these high-throughput genomic data to various clinical outcomes, including possibly censored survival outcomes such as age …


A General Framework For Statistical Performance Comparison Of Evolutionary Computation Algorithms, David Shilane, Jarno Martikainen, Sandrine Dudoit, Seppo Ovaska Mar 2006

A General Framework For Statistical Performance Comparison Of Evolutionary Computation Algorithms, David Shilane, Jarno Martikainen, Sandrine Dudoit, Seppo Ovaska

U.C. Berkeley Division of Biostatistics Working Paper Series

This paper proposes a statistical methodology for comparing the performance of evolutionary computation algorithms. A two-fold sampling scheme for collecting performance data is introduced, and these data are analyzed using bootstrap-based multiple hypothesis testing procedures. The proposed method is sufficiently flexible to allow the researcher to choose how performance is measured, does not rely upon distributional assumptions, and can be extended to analyze many other randomized numeric optimization routines. As a result, this approach offers a convenient, flexible, and reliable technique for comparing algorithms in a wide variety of applications.


Membrane-Based Protein Preconcentration Microfluidic Devices, Yi Li Mar 2006

Membrane-Based Protein Preconcentration Microfluidic Devices, Yi Li

Theses and Dissertations

Interest in microchip capillary electrophoresis (CE) is growing due to the rapid analysis times provided and small sample input requirements. However, higher-concentration samples are typically needed because of the small (~pL) detection volumes in these devices. I have made membrane-based protein preconcentration systems in capillary and microchip designs to increase the detectability of low-concentration biological samples. A photopolymerized ion-permeable membrane interfaced with a microchannel in poly(methyl methacrylate) (PMMA) formed the preconcentrator. When a voltage was applied between the sample reservoir and the ionically conductive membrane in a capillary-based system, R-phycoerythrin was concentrated more than 1,000 fold, as determined by laser-induced …