Physical Sciences and Mathematics Commons^™

Platform Pricing With Endogenous Network Effects, Mei Lin, Ruhai Wu, Wen Zhou

Research Collection School Of Computing and Information Systems

This paper examines a monopoly platform’s two-sided pricing strategy through modeling the trades between the participating sellers and buyers. In this approach, the network effects emerge endogenously through the equilibrium trading strategies of the two sides. We show that platform pricing depends crucially on the characteristics associated with market liquidity, including both sides’ entry costs, the buyers’ preferences, and the distribution of the sellers’ quality. The platform may subsidize sellers if the market is sufficiently liquid, whereas buyer subsidy can be optimal given an illiquid market. We also illustrate the impact of the sellers’ quality heterogeneity on the platform’s optimal …

Sensor-Free Corner Shape Detection By Wireless Networks, Yuxi Wang, Zimu Zhou, Kaishun Wu

Research Collection School Of Computing and Information Systems

Due to the rapid growth of the smartphone applications and the fast development of the Wireless Local Area Networks (WLANs), numerous indoor location-based techniques have been proposed during the past several decades. Floorplan, which defines the structure and functionality of a specific indoor environment, becomes a hot topic nowadays. Conventional floorplan techniques leverage smartphone sensors combined with WiFi signals to construct the floorplan of a building. However, existing approaches with sensors cannot detect the shape of a corner, and the sensors cost huge amount of energy during the whole floorplan constructing process. In this paper, we propose a sensor-free approach …

Pads: Passive Detection Of Moving Targets With Dynamic Speed Using Phy Layer Information, Kun Qian, Chenshu Wu, Zheng Yang, Yunhao Liu, Zimu Zhou

Research Collection School Of Computing and Information Systems

Device-free passive detection is an emerging technology to detect whether there exists any moving entities in the area of interests without attaching any device to them. It is an essential primitive for a broad range of applications including intrusion detection for safety precautions, patient monitoring in hospitals, child and elder care at home, etc. Despite of the prevalent signal feature Received Signal Strength (RSS), most robust and reliable solutions resort to finer-grained channel descriptor at physical layer, e.g., the Channel State Information (CSI) in the 802.11n standard. Among a large body of emerging techniques, however, few of them have explored …

Modeling The Evolution Of Generativity And The Emergence Of Digital Ecosystems, C. Jason Woodard, Eric K. Clemons

Research Collection School Of Computing and Information Systems

Recent literature on sociotechnical systems has employed the concept of generativity to explain the remarkable capacity for digital artifacts to support decentralized innovation and the emergence of rich business ecosystems. In this paper, we propose agent-based computational modeling as a tool for studying the evolution of generativity, and offer a set of building blocks for constructing agent-based models in which generativity evolves. We describe a series of models that we have created using these building blocks, and summarize the results of our computational experiments to date. We find in several different settings that key features of generative systems can themselves …

Measuring Student Performance And Providing Feedback Using Competency Framework, Joelle Elmaleh, Venky Shankararaman

Research Collection School Of Computing and Information Systems

A number of Computer Science and Information Systems programs have effectively defined learning outcomes, course level competencies, and conducted assessments at the program level to determine areas for continuous improvement. However, many of these programs do not fully leverage the course competencies during the actual delivery and assessment of the course. This paper presents how course competencies can be used to effectively deliver and assess the course content, and give valuable timely feedback to the students. Using a large first year core course of the BSc (Information Systems Management) program (called Object Oriented Application Development course-OOAD) as an example, this …

A Metrics Suite Of Cloud Computing Adoption Readiness, Robert J. Kauffman, Dan Ma, Martin Yu

Research Collection School Of Computing and Information Systems

Recent research on cloud computing adoption indicates that there has been a lack of deep understanding of its benefits by managers and organizations. This has been an obstacle for adoption. We report on an initial design for a firm-level cloud computing readiness metrics suite. We propose categories and measures to form a set of metrics to measure adoption readiness and assess the required adjustments in strategy and management, technology and operations, and business policies. We reviewed the relevant interdisciplinary literature and interviewed industry professionals to ground our metrics based on theory and practice knowledge. We identified four relevant categories for …

Probabilistic Latent Document Network Embedding, Tuan M. V. Le, Hady W. Lauw

Research Collection School Of Computing and Information Systems

A document network refers to a data type that can be represented as a graph of vertices, where each vertex is associated with a text document. Examples of such a data type include hyperlinked Web pages, academic publications with citations, and user profiles in social networks. Such data have very high-dimensional representations, in terms of text as well as network connectivity. In this paper, we study the problem of embedding, or finding a low-dimensional representation of a document network that "preserves" the data as much as possible. These embedded representations are useful for various applications driven by dimensionality reduction, such …

Detecting Camouflaged Applications On Mobile Application Markets, Mon Kywe Su, Yingjiu Li, Huijie Robert Deng, Jason Hong

Research Collection School Of Computing and Information Systems

Application plagiarism or application cloning is an emerging threat in mobile application markets. It reduces profits of original developers and sometimes even harms the security and privacy of users. In this paper, we introduce a new concept, called camouflaged applications, where external features of mobile applications, such as icons, screenshots, application names or descriptions, are copied. We then propose a scalable detection framework, which can find these suspiciously similar camouflaged applications. To accomplish this, we apply text-based retrieval methods and content-based image retrieval methods in our framework. Our framework is implemented and tested with 30,625 Android applications from the official …

Extracting Interest Tags From Twitter User Biographies, Ying Ding, Jing Jiang

Research Collection School Of Computing and Information Systems

Twitter, one of the most popular social media platforms, has been studied from different angles. One of the important sources of information in Twitter is users’ biographies, which are short self-introductions written by users in free form. Biographies often describe users’ background and interests. However, to the best of our knowledge, there has not been much work trying to extract information from Twitter biographies. In this work, we study how to extract information revealing users’ personal interests from Twitter biographies. A sequential labeling model is trained with automatically constructed labeled data. The popular patterns expressing user interests are extracted and …

Using Consumer Informedness As An Information Strategy, Ting Li, Robert John Kauffman, Eric Van Heck, Peter Vervest, Benedict Dellaert

Research Collection School Of Computing and Information Systems

Consumer informedness describes the degree to which consumers are aware of the specific attributes of products or services offered in the marketplace. Understanding how this level of informedness can amplify consumer behaviour provides firms with the opportunity to develop information-based strategies that can encourage their target segment make purchases.

I’Ve Heard You Have Problems: Cellular Signal Monitoring Through Ue Participatory Sensing, Huiguang Liang, Hyong Kim, Hwee-Pink Tan, Wai-Leong Yeow

Research Collection School Of Computing and Information Systems

The operating environment of cellular networks can be in a constant state of change. One Singaporean operator expressed difficulty with the coverage assertion (CA) problem of whether regulated minimum coverage is met, especially in urban areas. Currently, the operator manually appraises coverage through laborious and expensive walk/drive-tests. In this paper, we propose Tattle, a distributed, low-cost and comprehensive cellular network measurement collection and processing framework. We exemplify Tattle by leveraging on participating UEs to report on network coverage in real-time. Tattle exploits wireless local-area interfaces to exchange RSCP measurements amongst devices to preserve the co-locality of readings and conserve power. …

Unisense: A Unified And Sustainable Sensing And Transport Architecture For Large Scale And Heterogeneous Sensor Networks, Yunye Jin, Hwee-Pink Tan

Research Collection School Of Computing and Information Systems

In this paper, we propose UNISENSE, a unified and sustainable sensing and transport architecture for large scale and heterogeneous sensor networks. The proposed architecture incorporates seven principal components, namely, application profiling, node architecture, intelligent network design, network management, deep sensing, generalized participatory sensing, and security. We describe the design and implementation for each component. We also present the deployment and performance of the UNISENSE architecture in four practical applications.

An Empirical Study On The Adequacy Of Testing In Open Source Projects, Pavneet Singh Kochhar, Ferdian Thung, David Lo, Julia Lawall

Research Collection School Of Computing and Information Systems

During software maintenance, testing is crucial to ensure the quality of code as it evolves. With the increasing size and complexity of software, adequate software testing has become increasingly important. Code coverage is an important metric to gauge the effectiveness of test cases and the adequacy of testing. However, what is the coverage level exhibited by large-scale open-source projects? What is the correlation between software metrics and the code coverage of the software?In this study, we investigate the state-of-the-practice of testing by measuring code coverage in open-source software projects. We examine over300 large open-source projects written in Java, coming from …

Scientific Application Acceleration Utilizing Heterogeneous Architectures, Edwin Weill

All Theses

Within the past decade, there have been substantial leaps in computer architectures to exploit the parallelism that is inherently present in many applications. The scientific community has benefited from the emergence of not only multi-core processors, but also other, less traditional architectures including general purpose graphical processing units (GPGPUs), field programmable gate arrays (FPGAs), and Intel's many integrated cores (MICs) architecture (i.e. Xeon Phi). The popularity of the GPGPU has increased rapidly because of their ability to perform massive amounts of parallel computation quickly and at low cost with an ease of programmability. Also, with the addition of high-level programming …

A Vegetation Analysis On Horn Island, Mississippi, Ca. 1940 Using Characteristic Dimensions Derived From Historical Aerial Photography, Guy Wilburn Jeter Jr.

Master's Theses

Horn Island is part of the MS/AL barrier island chain in the northern Gulf of Mexico located approximately 18kn off the coast of Mississippi. This island’s habitats have undergone many transitions over the last several decades. The goal of this study was to quantify habitat change over a seventy year period using historical black and white photography from 1940. Using present NAIP imagery from the USDA, habitat structure was estimated by using geo-statistics, and second order statistics, from a co-occurrence matrix, to characterize texture for habitat classification. Percent land cover was then calculated to determine overall land cover change over …

The Application Of P-Bar Theory In Transformation-Based Error-Driven Learning, Bryant Harold Walley

Master's Theses

In P-bar Theory, Perkins et al. (2014) proposed a rule based method for determining the context of a partext (i.e., a part of a text document).

In Transformation-Based Error-Driven Learning and Natural Language Processing: A Case Study in Part-of-Speech Tagging Brill (1995) demonstrates a method of error-driven learning applied to individual words at the sentence level to determine the part of speech each word represents.

We combine these two concepts providing a transformation-based error-driven learning algorithm to improve the results obtained from the static rules Perkins proposed and determine if the rule order prediction will provide additional metadata.

Earth Abundant Thin Film Technology For Next Generation Photovoltaic Modules, Githin Alapatt

All Dissertations

With a cumulative generation capacity of over 100 GW, Photovoltaics (PV) technology is uniquely poised to become increasingly popular in the coming decades. Although, several breakthroughs have propelled PV technology, it accounts for only less than 1% of the energy produced worldwide. This aspect of the PV technology is primarily due to the somewhat high cost per watt, which is dependent on the efficiency of the PV cells as well as the cost of manufacturing and installing them. Currently, the efficiency of the PV conversion process is limited to about 25% for commercial terrestrial cells; improving this efficiency can increase …

Gender And Ethnicity Classification Using Partial Face In Biometric Applications, Jamie Lyle

All Dissertations

As the number of biometric applications increases, the use of non-ideal information such as images which are not strictly controlled, images taken covertly, or images where the main interest is partially occluded, also increases. Face images are a specific example of this. In these non-ideal instances, other information, such as gender and ethnicity, can be determined to narrow the search space and/or improve the recognition results. Some research exists for gender classification using partial-face images, but there is little research involving ethnic classifications on such images. Few datasets have had the ethnic diversity needed and sufficient subjects for each ethnicity …

Numerical Decoding, Johnson-Lindenstrauss Transforms, And Linear Codes, Yue Mao

All Dissertations

Many computational problems are related to the model y = Ax + e, including compressive sensing, coding theory, dimensionality reduction, etc. The related algorithms are extremely useful in practical applications for high performance computing, for example, digital communications, biological imaging and data streaming, etc. This thesis studies two important problems. One problem is related to efficient decoding for Reed-Solomon codes over complex numbers. In this case, A and y are given, and the goal is to find an efficient stable algorithm to compute x. This is related to magnetic resonance imaging (MRI). The other problem is related to fast algorithms …

Toward Understanding The Thermodynamics And Mechanisms Of Actinide Sorption Reactions, Shanna Estes

All Dissertations

The environmental fate of actinides is greatly influenced by interfacial reactions, including sorption onto solid surfaces. Because changes in the primary hydration sphere of the actinide are expected to greatly influence the thermodynamics (i.e., reaction enthalpy and entropy) of these reactions, examining actinide sorption thermodynamics may provide insight into actinide sorption mechanisms. Additionally, examining actinide sorption thermodynamics may enhance the ability to model or predict these reactions in environmental or engineered systems where variable or elevated temperatures are expected. However, few researchers have studied actinide sorption thermodynamics. Therefore, this research examined the thermodynamics of Eu(III) (a trivalent actinide analog), Th(IV), …

Neutron Study Of Structure And Dynamics Of Rigid Polymers, Naresh Osti

All Dissertations

The structure and the dynamics in two different classes of rigid polymers; ionomers and rigid luminescent polymers, have been investigated predominantly by neutron techniques. Rigidity of the backbones of both polymers affects their properties. For ionomers, it affects transport pathways, therefore, their applications for energy and separation membranes. In luminescent polymers, it determines the conformations of the chains and their electro-optical response. One group of the polymers consists of rigid hydrophobic para-phenylene backbone decorated with pendant phenyl side chains functionalized with sulfonic acid (SPP). The other family of polymers consists of poly para-phenyleneethynylene (PPE) backbone that becomes conjugated upon conformational …

Efficient And Reliable Simulation, Memory Protection, And Driver Generation In Embedded Network Systems, Jiannan Zhai

All Dissertations

Embedded systems are widely used, from consumer electronics, to industrial equipment, to spacecraft. With embedded systems becoming more complex, new challenges are presented to application developers. In this dissertation, we focus on three of the most important: (i) Network simulation tools are widely used for sensor network testing and evaluation. Simulation performance affects the efficiency of the application developers who use these tools. The performance of a single host system represents a performance bottleneck for large-scale network simulation. A distributed simulator offering higher performance is needed to support fast, large-scale network simulation. (ii) Single event upsets (SEUs), which occur when …

Surface Modifications Of Capillary-Channeled Polymer (C-Cp) Fiber Stationary Phases: Improving The Efficiency Of Highly Selective Analyte Separations, Abby Schadock-Hewitt

All Dissertations

High performance liquid chromatography (HPLC) is a fundamental methodology for the characterization and purification of macromolecules. Since its development in the 1970's, HPLC has significantly advanced its instrumentation and column technology to become a powerful analytical technique. A considerable amount of research focuses on advancements to the stationary phase, or solid support, on which molecules interact and separate. To overcome limitations of other phases that lead to poor mass transfer, slow speeds, and low efficiency, nonporous and superficially porous phases have been developed. Specifically, fiber based polymer stationary phases show great promise as stationary phases for protein separations. The Marcus …

A Comprehensive Assessment Methodology Based On Life Cycle Analysis For On-Board Photovoltaic Solar Modules In Vehicles, Mahmoud Abdelhamid

All Dissertations

This dissertation presents a novel comprehensive assessment methodology for using on-board photovoltaic (PV) solar technologies in vehicle applications. A well-to-wheels life cycle analysis based on a unique energy, greenhouse gas (GHG) emission, and economic perspective is carried out in the context of meeting corporate average fuel economy (CAFE) standards through 2025 along with providing an alternative energy path for the purpose of sustainable transportation. The study includes 14 different vehicles, 3 different travel patterns, in 12 U.S. states and 16 nations using 19 different cost analysis scenarios for determining the challenges and benefits of using on-board photovoltaic (PV) solar technologies …

A Function-To-Task Process Model For Adaptive Automation System Design, Jason M. Bindewald, Michael E. Miller, Gilbert L. Peterson

Faculty Publications

Adaptive automation systems allow the user to complete a task seamlessly with a computer performing tasks at which the human operator struggles. Unlike traditional systems that allocate functions to either the human or the machine, adaptive automation varies the allocation of functions during system operation. Creating these systems requires designers to consider issues not present during static system development. To assist in adaptive automation system design, this paper presents the concept of inherent tasks and takes advantage of this concept to create the function-to-task design process model. This process model helps the designer determine how to allocate functions to the …

Gradient-Based Compressive Sensing For Noise Image And Video Reconstruction, Huihuang Zhao, Yaonan Wang, Xiaojiang Peng, Zhijun Qiao

School of Mathematical & Statistical Sciences Faculty Publications

In this study, a fast gradient-based compressive sensing (FGB-CS) for noise image and video is proposed. Given a noise image or video, the authors first make it sparse by orthogonal transformation, and then reconstruct it by solving a convex optimisation problem with a novel gradient-based method. The main contribution is twofold. Firstly, they deal with the noise signal reconstruction as a convex minimisation problem, and propose a new compressive sensing based on gradient-based method for noise image and video. Secondly, to improve the computational efficiency of gradient-based compressive sensing, they formulate the convex optimisation of noise signal reconstruction under Lipschitz …

Improved Upper Limits On The Stochastic Gravitational-Wave Background From 2009–2010 Ligo And Virgo Data, J. Aasi, B. P. Abbott, H. Daveloza, Mario C. Diaz, S. R. Morriss, Soma Mukherjee, M. E. Normandin, O. Puncken, Volker Quetschke, Malik Rakhmanov, Karla E. Ramirez, Joseph D. Romano, Robert Stone

Physics & Astronomy Faculty Publications

Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of ΩGWðfÞ ¼ Ωαðf=fref Þα, we place …

Imaging, Spectroscopic, Mechanical And Biocompatibility Studies Of Electrospun Tecoflex® Eg 80a Nanofibers And Composites Thereof Containing Multiwalled Carbon Nanotubes, Javier Macossay-Torres, Faheem A. Sheikh, Travis Cantu, Thomas Eubanks, M. Esther Salinas, Chakavak S. Farhangi, Hassan Ahmad, M. Shamshi Hassan, Myung-Seob Khil, Shivani K. Maffi, Hern Kim, Gary L. Bowlin

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

The present study discusses the design, development and characterization of electrospun Tecoflex® EG 80A class of polyurethane nanofibers and the incorporation of multiwalled carbon nanotubes (MWCNTs) to these materials. Scanning electron microscopy results confirmed the presence of polymer nanofibers, which showed a decrease in fiber diameter at 0.5% wt. and 1% wt. MWCNTs loadings, while transmission electron microscopy showed evidence of the MWCNTs embedded within the polymer matrix. The fourier transform infrared spectroscopy and Raman spectroscopy were used to elucidate the polymer-MWCNTs intermolecular interactions, indicating that the C-N and N-H bonds in polyurethanes are responsible for the interactions with MWCNTs. …

A Multi-Method And Multi-Scale Approach For Estimating City-Wide Anthropogenic Heat Fluxes, Winston T. L. Chow, Francisco Salamanca, Matei Gergescu, Alex Mahalov, Jeffrey Milne, Benjamin L. Ruddell

Research Collection School of Social Sciences

A multi-method approach estimating summer waste heat emissions from anthropogenic activities (QF)was applied for a major subtropical city (Phoenix, AZ). These included detailed, quality-controlled in-ventories of city-wide population density and traffic counts to estimate waste heat emissions frompopulation and vehicular sources respectively, and also included waste heat simulations derived fromurban electrical consumption generated by a coupled building energyeregional climate model (WRF-BEMBEP). These componentQFdata were subsequently summed and mapped through GeographicInformation Systems techniques to enable analysis over local (i.e. census-tract) and regional (i.e.metropolitan area) scales. Through this approach, local mean dailyQFestimates compared reasonablyversus (1.) observed daily surface energy balance residuals from …

The Threat In Hampton Roads, Ray Toll, David W. Titley

News Items

No abstract provided.