Physical Sciences and Mathematics Commons^™

Offering Rss Feeds: Does It Help To Gain Competitive Advantage?, Dan Ma

Research Collection School Of Computing and Information Systems

Nowadays, many Websites have adopted the really simple syndication (RSS) technology to deliver online content to visitors. In this paper, I build an analytical model to examine how the offering of RSS feeds impact the number of visitors, total traffic load, and profit of Websites in a competitive setting. I show that although RSS can always attract more visitors, it may reduce the Website's profit. Interestingly, in a competitive market there are cases that the RSS feeds hurt the offering Website but benefit the competing Website instead. The conditions under which these will happen are derived. I also study the …

A Comprehensive Study For Rfid Malwares On Mobile Devices, Qiang Yan, Yingjiu Li, Tieyan Li, Robert Huijie Deng

Research Collection School Of Computing and Information Systems

Radio Frequency Identification (RFID) technique has been widely accepted as wireless identification standard in the business world. While RFID technique enables efficient collection of identification information, it also introduces new security risk due to the emerging of RFID malwares. This risk becomes increasingly severe due to the adoption of internet in RFID applications (e.g., track and trace in EPCglobal network) and the use of mobile devices as RFID readers. The prior work to defend the threat of RFID malwares has mainly focused on the protection of front-end tag-reader communications and back-end database systems. Less work has been conducted to defend …

Tuning On-Air Signatures For Balancing Performance And Confidentiality, Baihua Zheng, Wang-Chien Lee, Peng Liu, Dik Lun Lee, Xuhua Ding

Research Collection School Of Computing and Information Systems

In this paper, we investigate the trade off between performance and confidentiality in signature-based air indexing schemes for wireless data broadcast. Two metrics, namely, false drop probability and false guess probability, are defined to quantify the filtering efficiency and confidentiality loss of a signature scheme. Our analysis reveals that false drop probability and false guess probability share a similar trend as the tuning parameters of a signature scheme change and it is impossible to achieve a low false drop probability and a high false guess probability simultaneously. In order to balance the performance and confidentiality, we perform an analysis to …

Dynamic Web Service Selection For Reliable Web Service Composition, San-Yih Hwang, Ee Peng Lim, Chien-Hsiang Lee, Cheng-Hung Chen

Research Collection School Of Computing and Information Systems

This paper studies the dynamic web service selection problem in a failure-prone environment, which aims to determine a subset of Web services to be invoked at run-time so as to successfully orchestrate a composite web service. We observe that both the composite and constituent web services often constrain the sequences of invoking their operations and therefore propose to use finite state machine to model the permitted invocation sequences of Web service operations. We assign each state of execution an aggregated reliability to measure the probability that the given state will lead to successful execution in the context where each web …

Integrated Resource Allocation And Scheduling In Bidirectional Flow Shop With Multi-Machine And Cos Constraints, Hoong Chuin Lau, Zhengyi Zhao, Shuzhi Sam Ge

Research Collection School Of Computing and Information Systems

An integer programming (IP) model is proposed for integrated resource allocation and operation scheduling for a multiple job-agents system. Each agent handles a specific job-list in a bidirectional flowshop. For the individual agent scheduling problem, a formulation is proposed in continuous time domain and compared with an IP formulation in discrete time domain. Of particular interest is the formulation of the machine utilization function-- both in continuous time and discrete time. Fast heuristic methods are proposed with the relaxation of the machine capacity. For the integrated resource allocation and scheduling problem, a linear programming relaxation approach is applied to solve …

Event-Detecting Multi-Agent Mdps: Complexity And Constant-Factor Approximation, Akshat Kumar, S. Zilberstein

Research Collection School Of Computing and Information Systems

Planning under uncertainty for multiple agents has grown rapidly with the development of formal models such as multi-agent MDPs and decentralized MDPs. But despite their richness, the applicability of these models remains limited due to their computational complexity. We present the class of event-detecting multi-agent MDPs (eMMDPs), designed to detect multiple mobile targets by a team of sensor agents. We show that eMMDPs are NP-Hard and present a scalable 2-approximation algorithm for solving them using matroid theory and constraint optimization. The complexity of the algorithm is linear in the state-space and number of agents, quadratic in the horizon, and exponential …

The Role Of Stochastic Resonance And Physical Constraints In The Evolution Of Foraging Strategy, Nathan Daniel Dees

Doctoral Dissertations

"This work represents a detailed study of the optimization of this process: foraging within a single, finite food patch for a limited amount of time. The work is an example of the computational algorithms of statistical physics being applied to the ecological field of foraging behavior. The analysis begins with an examination of the probability distributions observed in the movement parameters of the zooplankton, Daphnia. While foraging, these small aquatic organisms stochastically choose movement parameters with particular levels of variation, or noise, which are similar across several species. Here, related simulations consistently show that these noise levels may be adjusted …

Spin Structure Of The Deuteron, Nevzat Guler

Physics Theses & Dissertations

Double spin asymmetries for the proton and the deuteron have been measured in the EG1b experiment using the CLAS detector at Jefferson Lab. Longitudinally polarized electrons at energies 1.6, 2.5, 4.2 and 5.7 GeV were scattered from longitudinally polarized NH3 and ND3 targets. The double spin asymmetry A|| for the proton and the deuteron has been extracted from these data as a function of W and Q² with unprecedented precision. The virtual photon asymmetry A₁ and the spin structure function g1 can be calculated from these measurements by using parametrization to the world data for the virtual …

Neutron Structure Functions Measured With Spectator Tagging, Svyatoslav Tkachenko

Physics Theses & Dissertations

We know much less about the neutron than the proton due to the absence of free neutron targets. Neutron information has to be extracted from data on nuclear targets like deuterium. This requires corrections for off-shell and binding effects which are not known from first principles and therefore are model-dependent. As a consequence, the same data can be interpreted in different ways, leading to different conclusions about important questions such as the value of the d/u quark ratio at large momentum fraction x. The Barely Off-shell NUcleon Structure (BONUS) experiment at Jefferson Lab addressed this problem by tagging spectator protons …

A Subspace Projection Methodology For Nonlinear Manifold Based Face Recognition, Praveen Sankaran

Electrical & Computer Engineering Theses & Dissertations

A novel feature extraction method that utilizes nonlinear mapping from the original data space to the feature space is presented in this dissertation. Feature extraction methods aim to find compact representations of data that are easy to classify. Measurements with similar values are grouped to same category, while those with differing values are deemed to be of separate categories. For most practical systems, the meaningful features of a pattern class lie in a low dimensional nonlinear constraint region (manifold) within the high dimensional data space. A learning algorithm to model this nonlinear region and to project patterns to this feature …

Location, Location, Location: A Transaction Comparison Of Catalog Searches Originating From The Library Homepage And Aleph, Jimmy Ghaphery, Thomas Mcnulty, Susan Teague Rector

VCU Libraries Faculty and Staff Presentations

Jimmy Ghaphery, Head, Library Information Systems, Virginia Commonwealth University (VCU); Thomas McNulty, Integrated Library Systems Librarian, VCU; Susan Teague-Rector, Web Applications Manager, VCU. We will analyze several weeks of search terms from February 2009 in order to determine how different points of entry impact user searches. Specifically we will compare user searches originating from a search tool on the library homepage and searches originating directly from Aleph. This session should be of interest to those who are involved with usability and OPAC design as well as system administrators tasked with measuring OPAC activity.

Andy Nuñez: His Life, Career, & Contributions, Bridgette Burbank, Jerold Widdison

Water Matters!

For years and years, reaching back well before his time in the Legislature, Rep. Nuñez has been a strong advocate not only for the state’s people but for its land and water resources.

Singular Superposition/Boundary Element Method For Reconstruction Of Multi-Dimensional Heat Flux Distributions With Application To Film Cooling Holes, Mahmood Silieti, Eduardo Divo, Alain J. Kassab

Publications

A hybrid singularity superposition/boundary element-based inverse problem method for the reconstruction of multi-dimensional heat flux distributions is developed. Cauchy conditions are imposed at exposed surfaces that are readily reached for measurements while convective boundary conditions are unknown at surfaces that are not amenable to measurements such as the walls of the cooling holes. The purpose of the inverse analysis is to determine the heat flux distribution along cooling hole surfaces. This is accomplished in an iterative process by distributing a set of singularities (sinks) inside the physical boundaries of the cooling hole (usually along cooling hole centerline) with a given …

The Architecture Of Platforms: A Unified View, Carliss Y. Baldwin, C. Jason Woodard

Research Collection School Of Computing and Information Systems

Product and system designers have long exploited opportunities to create families of complex artifacts by developing and recombining modular components. An especially common design pattern has come to be associated with the concept of a ‘platform’, which we define as a set of stable components that supports variety and evolvability in a system by constraining the linkages among the other components. Our goal in this chapter is to shed light on the relationships between platforms and the systems in which they are embedded, in order to better understand firms and industries where platforms play an important role. We begin by …

An Introduction To Dezert-Smarandache Theory (Dsmt), Jean Dezert, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The management and combination of uncertain, imprecise, fuzzy and even paradoxical or highly conflicting sources of information has always been, and still remains today, of primal importance for the development of reliable modern information systems involving artificial reasoning. In this introduction, we present a survey of our recent theory of plausible and paradoxical reasoning, known as Dezert-Smarandache Theory (DSmT), developed for dealing with imprecise, uncertain and conflicting sources of information. We focus our presentation on the foundations of DSmT and on its most important rules of combination, rather than on browsing specific applications of DSmT available in literature. Several simple …

Advances And Applications Of Dezert-Smarandache Theory (Dsmt) For Information Fusion (Collected Works), Vol. 3, Florentin Smarandache, Jean Dezert

Branch Mathematics and Statistics Faculty and Staff Publications

This volume has about 760 pages, split into 25 chapters, from 41 contributors. First part of this book presents advances of Dezert-Smarandache Theory (DSmT) which is becoming one of the most comprehensive and flexible fusion theory based on belief functions. It can work in all fusion spaces: power set, hyper-power set, and super-power set, and has various fusion and conditioning rules that can be applied depending on each application. Some new generalized rules are introduced in this volume with codes for implementing some of them. For the qualitative fusion, the DSm Field and Linear Algebra of Refined Labels (FLARL) is …

Studies In Statistical Inference, Sampling Techniques And Demography, Florentin Smarandache, Rajesh Singh, Jayant Singh

Branch Mathematics and Statistics Faculty and Staff Publications

This volume is a collection of five papers. Two chapters deal with problems in statistical inference, two with inferences in finite population, and one deals with demographic problem. The ideas included here will be useful for researchers doing works in these fields. The following problems have been discussed in the book: Chapter 1. In this chapter optimum statistical test procedure is discussed. The test procedures are optimum in the sense that they minimize the sum of the two error probabilities as compared to any other test. Several examples are included to illustrate the theory. Chapter 2. In testing of hypothesis …

Special Set Linear Algebra And Special Set Fuzzy Linear Algebra, Florentin Smarandache, W.B. Vasantha Kandasamy, K. Ilanthenral

Branch Mathematics and Statistics Faculty and Staff Publications

This book for the first time introduces the notion of special set linear algebra and special set fuzzy linear algebra. This is an extension of the book set linear algebra and set fuzzy linear algebra. These algebraic structures basically exploit only the set theoretic property, hence in applications one can include a finite number of elements without affecting the systems property. These new structures are not only the most generalized structures but they can perform multi task simultaneously; hence they would be of immense use to computer scientists. This book has five chapters. In chapter one the basic concepts about …

Superbimatrices And Their Generalizations, Florentin Smarandache, W.B Vasantha Kandasamy

Branch Mathematics and Statistics Faculty and Staff Publications

The systematic study of supermatrices and super linear algebra has been carried out in 2008. These new algebraic structures find their applications in fuzzy models, Leontief economic models and data-storage in computers. In this book the authors introduce the new notion of superbimatrices and generalize it to super trimatrices and super n-matrices. Study of these structures is not only interesting and innovative but is also best suited for the computerized world. The main difference between simple bimatrices and super bimatrices is that in case of simple bimatrices we have only one type of product defined on them, whereas in case …

Environmental Catalysis By Nanostructured Chromium Oxides: Methanol Conversion To Dimethyl Ether As A Clean Fuel Alternative, Mariam Humaid Salem Al-Shamisi

Theses

Heterogeneous catalysts which are mainly based on metal particles and metal oxides have shown promising activity and selectivity in several environmental and industrial important reactions. Catalysis plays a key role in chemical and material manufacturing, fuel cells as well as other energy conversion and pollution control systems. Petroleum and fuel industry, in particular, rely largely on heterogeneous catalysis. Since catalysts play such a critical role in essential processes, the search for more effective and selective catalysts continues to be of great importance for both environmental and commercial considerations. The current study focuses on the catalytic conversion of methanol to other …

Arecibo Pulsar Survey Using Alpha: Probing Radio Pulsar Intermittency And Transients, J. S. Deneva, J. M. Cordes, M. A. Mclaughlin, D. J. Nice, D. R. Lorimer, F. Crawford, N. D.R. Bhat, F. Camilo, Fredrick A. Jenet, J. Van Leeuwen

Physics & Astronomy Faculty Publications

We present radio transient search algorithms, results, and statistics from the ongoing Arecibo Pulsar ALFA (PALFA) survey of the Galactic plane. We have discovered seven objects through a search for isolated dispersed pulses. All of these objects are Galactic and have measured periods between 0.4 and 4.7 s. One of the new discoveries has a duty cycle of 0.01%, smaller than that of any other radio pulsar. We discuss the impact of selection effects on the detectability and classification of intermittent sources, and compare the efficiencies of periodicity and single-pulse (SP) searches for various pulsar classes. For some cases we …

Stellar Population Models And Individual Element Abundances. Ii. Stellar Spectra And Integrated Light Models, Hyun Chul Lee, Guy Worthey, Aaron Dotter, Brian Chaboyer, Darko Jevremović, E. Baron, Michael M. Briley, Jason W. Ferguson, Paula Coelho, Scott C. Trager

Physics & Astronomy Faculty Publications

The first paper in this series explored the effects of altering the chemical mixture of the stellar population on an element-by-element basis on stellar evolutionary tracks and isochrones to the end of the red giant branch. This paper extends the discussion by incorporating the fully consistent synthetic stellar spectra with those isochrone models in predicting integrated colors, Lick indices, and synthetic spectra. Older populations display element ratio effects in their spectra at higher amplitude than younger populations. In addition, spectral effects in the photospheres of stars tend to dominate over effects from isochrone temperatures and lifetimes, but, further, the isochrone-based …

Xafs Debye-Waller Factors For Deformed Hemes And Metal Substituted Hemes, Nicholas Dimakis, T. Mion, C. Ramirez, G. Bunker

Physics & Astronomy Faculty Publications

We present an efficient and accurate method for calculating XAFS Debye-Waller factors for deformed active sites of hemoproteins and metal substituted hemes. Based on the Normal Coordinate Structural Decomposition scheme, the deformation of the porphyrin macrocycle is expressed as a linear combination of the normal modes of the planar species. In our approach, we identify the modes that contribute most to the deformation. Small metal-porphyrin structures which match the macrocycle structural deformation of the deformed hemoprotein site are used to calculate the Debye-Waller parameters at sample's temperature. The Debye-Waller factors are directly obtained by calculating the normal mode spectrum of …

Computerized Provider Order Entry Adoption: Implications For Clinical Workflow, Emily M. Campbell, Kenneth P. Guappone, Dean F. Sittig, Richard H. Dykstra, Joan S. Ash

Faculty, Staff and Student Publications

OBJECTIVE: To identify and describe unintended adverse consequences related to clinical workflow when implementing or using computerized provider order entry (CPOE) systems. METHODS: We analyzed qualitative data from field observations and formal interviews gathered over a three-year period at five hospitals in three organizations. Five multidisciplinary researchers worked together to identify themes related to the impacts of CPOE systems on clinical workflow. RESULTS: CPOE systems can affect clinical work by 1) introducing or exposing human/computer interaction problems, 2) altering the pace, sequencing, and dynamics of clinical activities, 3) providing only partial support for the work activities of all types of …

Strong Field Effects On Pulsar Arrival Times: Circular Orbits And Equatorial Beams, Yan Wang, Fredrick Jenet, Teviet Creighton, Richard H. Price

Physics & Astronomy Faculty Publications

If a pulsar orbits a supermassive black hole, the timing of pulses that pass close to the hole will show a variety of strong field effects. To compute the intensity and timing of pulses that have passed close to a nonrotating black hole, we introduce here a simple formalism based on two \"universal functions,\" one for the bending of photon trajectories and the other for the photon travel time on these trajectories. We apply this simple formalism to the case of a pulsar in circular orbit that beams its pulses into the orbital plane. In addition to the \"primary\" pulses …

Search For Gravitational Waves From Low Mass Compact Binary Coalescence In 186 Days Of Ligo’S Fifth Science Run, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, K. Hayama, H. Lei, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano, Robert Stone, Lappoon R. Tang

Physics & Astronomy Faculty Publications

We report on a search for gravitational waves from coalescing compact binaries, of total mass between 2 and 35M⊙, using LIGO observations between November 14, 2006 and May 18, 2007. No gravitational-wave signals were detected. We report upper limits on the rate of compact binary coalescence as a function of total mass. The LIGO cumulative 90%-confidence rate upper limits of the binary coalescence of neutron stars, black holes and black hole-neutron star systems are 1.4×10−2, 7.3×10−4 and 3.6×10−3  yr−1 L−110, respectively, where L10 is 1010 times the blue solar luminosity.

Search For Gravitational-Wave Bursts In The First Year Of The Fifth Ligo Science Run, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, Hansheng Lei, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present the results obtained from an all-sky search for gravitational-wave (GW) bursts in the 64–2000 Hz frequency range in data collected by the LIGO detectors during the first year (November 2005—November 2006) of their fifth science run. The total analyzed live time was 268.6 days. Multiple hierarchical data analysis methods were invoked in this search. The overall sensitivity expressed in terms of the root-sum-square (rss) strain amplitude hrss for gravitational-wave bursts with various morphologies was in the range of 6×10−22  Hz−1/2 to a few×10−21  Hz−1/2. No GW signals were observed and a frequentist upper limit of 3.75 events per …

Strict-Dominance Solvability Of Games On Continuous Strategy Spaces, Andrew Campbell Elkington

Theses and Dissertations (Comprehensive)

The concept of strict dominance provides a technique that can be used normatively to predict the play of games based only on the assumption of individual rationality. Such predictions, unlike those based on Nash equilibria, do not depend on players’ beliefs about the behaviour of others. One strategy strictly dominates another if and only if the payoff from the first strategy is strictly greater than the payoff from the second, no matter how the opponent(s) plays. It is possible for iterated elimination of strictly dominated strategies to remove all but a single choice for each player, in which case we …

Applications Of New Diffusion Models To Barrier Option Pricing And First Hitting Time In Finance, Keang Ly

Theses and Dissertations (Comprehensive)

The main focus of this thesis is in the application of a new family of analytical solvable diffusion models to arbitrage-free pricing exotic financial derivatives, such as barrier options. The family of diffusions is the so-called “Drifted Bessel family” having nonlinear (smile-like) local volatility with multiple adjustable parameters. In particular, the drifted Bessel-K diffusion is used to model asset (stock) price processes under a risk-neutral measure whereby discounted asset price are martingales.

Closed-form spectral expansions for barrier option values are derived within the Bessel-K family of models. This follow from the closed-form spectral expansions for the transition probability …

Simulation Studies On Estimation Of Variance Components For Multilevel Models, Sara Vakilian

Theses and Dissertations (Comprehensive)

With the presence of unequal sampling in a multilevel model, the weight inflated estimators for variance components can be biased even though the use of survey weights results in design consistent estimators of the parameters. In this thesis I will carry out a simulation study to examine the performance of current existing methods and I will examine the resampling method for correcting bias of estimators of variance components of a multilevel model with covariates. This study will be based on these three papers: “Weighting for Unequal Selection Probabilities in Multilevel Models” by D. Pfeffermann , C. J. Skinner, D.J. Holmes, …