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2007

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Designing The Market Game For A Commodity Trading Simulation, Shih-Fen Cheng Nov 2007

Designing The Market Game For A Commodity Trading Simulation, Shih-Fen Cheng

Research Collection School Of Computing and Information Systems

In this paper, we propose to design a market game that (a) can be used in modeling and studying commodity trading scenarios, and (b) can be used in capturing human traders' behaviors. Specifically, we demonstrate the usefulness of this commodity trading game in a single-commodity futures trading scenario. A pilot experiment was run with a mixture of human traders and an autonomous agent that emulates the aggregatedmarket condition, with the assumption that this autonomous agent would hint each of its action through a public announcement. We show that the information collected from this simulation can be used to extract the …

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Multi-Period Combinatorial Auction Mechanism For Distributed Resource Allocation And Scheduling, Hoong Chuin Lau, Shih-Fen Cheng, Thin Yin Leong, Jong Han Park, Zhengyi Zhao Nov 2007

Multi-Period Combinatorial Auction Mechanism For Distributed Resource Allocation And Scheduling, Hoong Chuin Lau, Shih-Fen Cheng, Thin Yin Leong, Jong Han Park, Zhengyi Zhao

Research Collection School Of Computing and Information Systems

We consider the problem of resource allocation and scheduling where information and decisions are decentralized, and our goal is to propose a market mechanism that allows resources from a central resource pool to be allocated to distributed decision makers (agents) that seek to optimize their respective scheduling goals. We propose a generic combinatorial auction mechanism that allows agents to competitively bid for the resources needed in a multi-period setting, regardless of the respective scheduling problem faced by the agent, and show how agents can design optimal bidding strategies to respond to price adjustment strategies from the auctioneer. We apply our …

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The Price Of Stability In Selfish Scheduling Games, Lucas Agussurja, Hoong Chuin Lau Nov 2007

The Price Of Stability In Selfish Scheduling Games, Lucas Agussurja, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Game theory has gained popularity as an approach to analysing and understanding distributed systems with selfinterested agents. Central to game theory is the concept of Nash equilibrium as a stable state (solution) of the system, which comes with a price - the loss in efficiency. The quantification of the efficiency loss is one of the main research concerns. In this paper, we study the quality and computational characteristic of the best Nash equilibrium in two selfish scheduling models: the congestion model and the sequencing model. In particular, we present the following results: (1) In the congestion model: first, the best …

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Light-Weight Encryption Schemes For Multimedia Data, Feng Bao, Robert H. Deng Nov 2007

Light-Weight Encryption Schemes For Multimedia Data, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

Due to the pervasiveness of high-speed networks and multimedia communications and storage, the demand for highspeed cryptosystems is ever increasing. It is widely believed that there is a tradeoff between speed and security in cryptosystem design. No existing encryption algorithms are both fast enough for high-speed operation and sufficiently secure to withstand powerful cryptanalysis. In this paper, we propose and analyze a generic construction of high-speed encryption schemes. Our solution is based on the fact that there exist secure but relatively slow block ciphers, e. g. AES, and super-fast but relatively weaker stream ciphers. We then combine a secure block …

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Advances And Challenges With Data Broadcasting In Wireless Mesh Networks, Chun Tung Chou, Junaid Qadir, Joo Ghee Lim, Archan Misra Nov 2007

Advances And Challenges With Data Broadcasting In Wireless Mesh Networks, Chun Tung Chou, Junaid Qadir, Joo Ghee Lim, Archan Misra

Research Collection School Of Computing and Information Systems

Wireless mesh networks have become a promising means to provide low-cost broadband access. Many WMN applications require broadcasting data (IPTV etc.) over the WMN. This article studies how efficient data broadcast, measured in terms of broadcast latency, can be realized by exploiting two features of WMNs: the use of multiple transmission rates at the link layer and the use of multiple radio interfaces on each node. We demonstrate that by exploiting these features, broadcast latency can be reduced severalfold compared to the current default practice in wireless LANs of using the lowest transmission rate for broadcast traffic. We also discuss …

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Detecting And Segmenting Un-Occluded Items By Actively Casting Shadows, Tze K Koh, Amit Agrawal, Ramesh Raskar, Steve Morgan, Nicholas Miles, Barrie Hayes-Gill Nov 2007

Detecting And Segmenting Un-Occluded Items By Actively Casting Shadows, Tze K Koh, Amit Agrawal, Ramesh Raskar, Steve Morgan, Nicholas Miles, Barrie Hayes-Gill

Research Collection College of Integrative Studies

We present a simple and practical approach for segmenting un-occluded items in a scene by actively casting shadows. By ‘items’, we refer to objects (or part of objects) enclosed by depth edges. Our approach utilizes the fact that under varying illumination, un-occluded items will cast shadows on occluded items or background, but will not be shadowed themselves.We employ an active illumination approach by taking multiple images under different illumination directions, with illumination source close to the camera. Our approach ignores the texture edges in the scene and uses only the shadow and silhouette information to determine the occlusions. We show …

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Sloque: Slot-Based Query Expansion For Complex Questions, Maggy Anastasia Suryanto, Ee Peng Lim, Aixin Sun, Roger Hsiang-Li Chiang Nov 2007

Sloque: Slot-Based Query Expansion For Complex Questions, Maggy Anastasia Suryanto, Ee Peng Lim, Aixin Sun, Roger Hsiang-Li Chiang

Research Collection School Of Computing and Information Systems

Searching answers to complex questions is a challenging IR task. In this paper, we examine the use of query templates with semantic slots to formulate slot-based queries. These queries have query terms assigned to entity and relationship slots. We develop several query expansion methods for slot-based queries so as to improve their retrieval effectiveness on a document collection. Each method consists of a combination of term scoring scheme, term scoring formula, and term assignment scheme. Our preliminary experiments evaluate these different slot-based query expansion methods on a collection of news documents,and conclude that:(1) slot-based queries yield better retrieval accuracy compared …

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On Improving Wikipedia Search Using Article Quality, Meiqun Hu, Ee Peng Lim, Aixin Sun, Hady Wirawan Lauw, Ba-Quy Vuong Nov 2007

On Improving Wikipedia Search Using Article Quality, Meiqun Hu, Ee Peng Lim, Aixin Sun, Hady Wirawan Lauw, Ba-Quy Vuong

Research Collection School Of Computing and Information Systems

Wikipedia is presently the largest free-and-open online encyclopedia collaboratively edited and maintained by volunteers. While Wikipedia offers full-text search to its users, the accuracy of its relevance-based search can be compromised by poor quality articles edited by non-experts and inexperienced contributors. In this paper, we propose a framework that re-ranks Wikipedia search results considering article quality. We develop two quality measurement models, namely Basic and PeerReview, to derive article quality based on co-authoring data gathered from articles' edit history. Compared with Wikipedia's full-text search engine, Google and Wikiseek, our experimental results showed that (i) quality-only ranking produced by PeerReview gives …

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Comment-Oriented Blog Summarization By Sentence Extraction, Meishan Hu, Ee Peng Lim, Aixin Sun Nov 2007

Comment-Oriented Blog Summarization By Sentence Extraction, Meishan Hu, Ee Peng Lim, Aixin Sun

Research Collection School Of Computing and Information Systems

Much existing research on blogs focused on posts only, ignoring their comments. Our user study conducted on summarizing blog posts, however, showed that reading comments does change one's understanding about blog posts. In this research, we aim to extract representative sentences from a blog post that best represent the topics discussed among its comments. The proposed solution first derives representative words from comments and then selects sentences containing representative words. The representativeness of words is measured using ReQuT (i.e., Reader, Quotation, and Topic). Evaluated on human labeled sentences, ReQuT together with summation-based sentence selection showed promising results.

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Model Checking In The Absence Of Code, Model And Properties, David Lo, Siau-Cheng Khoo Nov 2007

Model Checking In The Absence Of Code, Model And Properties, David Lo, Siau-Cheng Khoo

Research Collection School Of Computing and Information Systems

Model checking is a major approach in ensuring software correctness. It verifies a model converted from code against some formal properties. However, difficulties and programmers ’ reluctance to formalize formal properties have been some hurdles to its widespread industrial adoption. Also, with the advent of commercial off-the-shelf (COTS) components provided by third party vendors, model checking is further challenged as often only a binary version of the code is provided by vendors. Interestingly, latest instrumentation tools like PIN and Valgrind have enable execution traces to be collected dynamically from a running program. In this preliminary study, we investigate what can …

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Measuring Article Quality In Wikipedia: Models And Evaluation, Meiqun Hu, Ee Peng Lim, Aixin Sun, Hady W. Lauw, Ba-Quy Vuong Nov 2007

Measuring Article Quality In Wikipedia: Models And Evaluation, Meiqun Hu, Ee Peng Lim, Aixin Sun, Hady W. Lauw, Ba-Quy Vuong

Research Collection School Of Computing and Information Systems

Wikipedia has grown to be the world largest and busiest free encyclopedia, in which articles are collaboratively written and maintained by volunteers online. Despite its success as a means of knowledge sharing and collaboration, the public has never stopped criticizing the quality of Wikipedia articles edited by non-experts and inexperienced contributors. In this paper, we investigate the problem of assessing the quality of articles in collaborative authoring of Wikipedia. We propose three article quality measurement models that make use of the interaction data between articles and their contributors derived from the article edit history. Our Basic model is designed based …

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State-Led Transborder Industrialization In Asia: A Note On Singapore's Manufacturing Enclaves In Vietnam And China, Caroline Yeoh, Wilfred Pow Ngee How Nov 2007

State-Led Transborder Industrialization In Asia: A Note On Singapore's Manufacturing Enclaves In Vietnam And China, Caroline Yeoh, Wilfred Pow Ngee How

Research Collection Lee Kong Chian School Of Business

State-led, market-driven interventions have been the hallmark of the Singapore `success storyÆ. This paper revisits SingaporeÆs state-enterprise strategy and takes a closer look at the portability of this strategy, in the framework of Regionalization21, a series of transborder industrialization experiments in Indonesia, Vietnam and China. These state-engineered projects, orchestrated to encapsulate economic space for Singapore-based firms to expand into the region, remain controversial. This strategic initiative is promulgated on the exportability of SingaporeÆs state credibility, systemic and operational efficiencies as well as technological competencies, to locations where these attributes are less distinct. We present evidence culled from surveys and interviews …

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⁵⁷Fe Mössbauer Spectral And Muon Spin Relaxation Study Of The Magnetodynamics Of Monodispersed Γ-Fe₂O₃ Nanoparticles, Leïla Rebbouh, Raphäel P. Hermann, Fernande Grandjean, Taeghwan Hyeon, Kwangjin An, Alex Amato, Gary J. Long Nov 2007

⁵⁷Fe Mössbauer Spectral And Muon Spin Relaxation Study Of The Magnetodynamics Of Monodispersed Γ-Fe₂O₃ Nanoparticles, Leïla Rebbouh, Raphäel P. Hermann, Fernande Grandjean, Taeghwan Hyeon, Kwangjin An, Alex Amato, Gary J. Long

Chemistry Faculty Research & Creative Works

The Mössbauer spectra of monodispersed iron oxide nanoparticles with diameters of 4, 7, 9, and 11 nm have been measured between 4.2 and 315 K and fitted within the formalism for stochastic fluctuations of the hyperfine Hamiltonian. In this model, the hyperfine field is assumed to relax between the six ±x, ±y, and ±z directions in space with a distribution of relaxation rates that is temperature dependent. Muon spin relaxation measurements have been carried out on the 9 nm particles between 4.2 and 295 K. Both techniques reveal three regimes in the magnetic dynamics of these nanoparticles. In the low-temperature …

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Electrostatic Force Microscopy Studies Of Boron-Doped Diamond Films, Santosh Gupta, O. A. Williams, Eric W. Bohannan Nov 2007

Electrostatic Force Microscopy Studies Of Boron-Doped Diamond Films, Santosh Gupta, O. A. Williams, Eric W. Bohannan

Computer Science Faculty Research & Creative Works

Much has been learned from electrochemical properties of boron-doped diamond (BDD) thin films synthesized using microwave plasma-assisted chemical vapor deposition about the factors influencing electrochemical activity, but some characteristics are still not entirely understood, such as its electrical conductivity in relation with microscale structure. Therefore, to effectively utilize these materials, understanding both the microscopic structure and physical (electrical, in particular) properties becomes indispensable. in addition to topography using atomic force microscopy, electrostatic force microscopy (EFM) in phase mode measuring the long-range electrostatic force gradients, helps to map the electrical conductivity heterogeneity of boron-doped micro-/nanocrystalline diamond surfaces. the mapping of electrical …

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An Information-Sharing Based Anti-Phishing System, Yueqing Cheng, Zhen Yuan, Lei Ma, Robert H. Deng Nov 2007

An Information-Sharing Based Anti-Phishing System, Yueqing Cheng, Zhen Yuan, Lei Ma, Robert H. Deng

Research Collection School Of Computing and Information Systems

This paper presents the design of an informationsharing based or server-assisted anti-phishing system. The system follows a client-server architecture and makes decision based on not only client side heuristics but also collective information from multiple clients. When visiting a web site, a client side proxy, installed as a plug-in to a browser, decides on the legitimacy of the web site based on a combination of white list, black list and heuristics. In case the client side proxy does not have sufficient information to make a clear judgment, it reports the suspicious site to a central server which has access to …

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Effects Of Electromagnetic Interference On Control Area Network Performance, Fei Ren, Y. Rosa Zheng, Maciej Jan Zawodniok, Jagannathan Sarangapani Nov 2007

Effects Of Electromagnetic Interference On Control Area Network Performance, Fei Ren, Y. Rosa Zheng, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the effects of electromagnetic interference (EMI) on control area network (CAN) communications are investigated by hardware experiments. Distinct CAN bit rates, communication cables, and networks are used to test effects of EMI on CAN bus. Waveforms of CAN data frames in EMI environment are observed and analyzed for figuring out details of effects. Experiments show that the EMI pulses frequently encountered in automobile and off-road machinery can cause the reduction of bit rates and errors in high-speed CAN communications. Replacing traditional unshielded parallel communication cables with shielded communication cables is proved to be an effective method of …

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Predictive Congestion Control Protocol For Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani Nov 2007

Predictive Congestion Control Protocol For Wireless Sensor Networks, Maciej Jan Zawodniok, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

Available congestion control schemes, for example transport control protocol (TCP), when applied to wireless networks, result in a large number of packet drops, unfair scenarios and low throughputs with a significant amount of wasted energy due to retransmissions. To fully utilize the hop by hop feedback information, this paper presents a novel, decentralized, predictive congestion control (DPCC) for wireless sensor networks (WSN). The DPCC consists of an adaptive flow and adaptive back-off interval selection schemes that work in concert with energy efficient, distributed power control (DPC). The DPCC detects the onset of congestion using queue utilization and the embedded channel …

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Comparative Application Of Differential Evolution And Particle Swarm Techniques To Reactive Power And Voltage Control, G. A. Bakare, G. Krost, Ganesh K. Venayagamoorthy, U. O. Aliyu Nov 2007

Comparative Application Of Differential Evolution And Particle Swarm Techniques To Reactive Power And Voltage Control, G. A. Bakare, G. Krost, Ganesh K. Venayagamoorthy, U. O. Aliyu

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents the comparative application of two metaheuristic approaches: Differential Evolution (DE) and Particle Swarm Optimization (PSO) to the solution of the reactive power and voltage control problem. Efficient distribution of reactive power in an electric network leads to minimization of the system losses and improvement of the system voltage profile. It can be achieved by varying the excitation of generators or the on-load tap changer positions of transformers as well as by switching of discrete portions of inductors or capacitors etc. This constitutes a typical mixed integer non-linear optimization problem for the solution of which metaheuristic techniques have …

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Campus Chronicle (Vol. 10, No. 12), Valparaiso University Nov 2007

Campus Chronicle (Vol. 10, No. 12), Valparaiso University

Campus Chronicle

No abstract provided.

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A Gray-Code Type Bit Assignment Algorithm For Unitary Space-Time Constellations, Adam Panagos, Kurt Louis Kosbar Nov 2007

A Gray-Code Type Bit Assignment Algorithm For Unitary Space-Time Constellations, Adam Panagos, Kurt Louis Kosbar

Electrical and Computer Engineering Faculty Research & Creative Works

Many techniques for constructing unitary space- time constellations have been proposed. To minimize bit-error rate (BER) in a wireless communication system, constellations constructed using these techniques should be given a Gray- code type bit assignment, where symbols which are close in signal space have bit assignments which have small Hamming distance. To the authors' knowledge, no efficient general strategy for making this bit assignment has been suggested. This work proposes a prioritized distance (PD) algorithm for making this assignment in an optimal manner by minimizing the probability of bit error union bound. The algorithm can be used on constellations constructed …

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The Existence Of Multiple Equilibria In The Upfc Power Injection Model, Mahyar Zarghami, Mariesa Crow Nov 2007

The Existence Of Multiple Equilibria In The Upfc Power Injection Model, Mahyar Zarghami, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This letter shows the existence of multiple equilibria that arise from the use of the state model of the unified power flow controller (UPFC). These multiple equilibria can arise from a common power injection model for the same terminal conditions of shunt bus voltage and series active and reactive power injections. The multiple equilibria result in two or more sets of eigenvalues, some of which may indicate an unstable operating condition. Therefore, the use of the UPFC power injection model must be used with caution to ensure stable operation of the UPFC.

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Modeling Noise Coupling Between Package And Pcb Power/Ground Planes With An Efficient 2-D Fdtd/Lumped Element Method, Ting-Kuang Wang, Sin-Ting Chen, Chi-Wei Tsai, Sung-Mao Wu, James L. Drewniak, Tzong-Lin Wu Nov 2007

Modeling Noise Coupling Between Package And Pcb Power/Ground Planes With An Efficient 2-D Fdtd/Lumped Element Method, Ting-Kuang Wang, Sin-Ting Chen, Chi-Wei Tsai, Sung-Mao Wu, James L. Drewniak, Tzong-Lin Wu

Electrical and Computer Engineering Faculty Research & Creative Works

An efficient numerical approach based on the 2-D finite-difference time-domain (FDTD) method is proposed to model the power/ground plane noise or simultaneously switching noise (SSN), including the interconnect effect between the package and the print circuit board (PCB). The space between the power and ground planes on the package and PCB are meshed with 2-D cells. The equivalent R-L-C circuits of the via and the solder balls connecting the package and PCB can be incorporated into a 2-D Yee cell based on a novel integral formulation in the time domain. An efficient recursive updating algorithm is proposed to fit the …

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Estimation Of High-Frequency Currents From Near-Field Scan Measurements, Haixiao Weng, Daryl G. Beetner, Richard E. Dubroff, Jin Shi Nov 2007

Estimation Of High-Frequency Currents From Near-Field Scan Measurements, Haixiao Weng, Daryl G. Beetner, Richard E. Dubroff, Jin Shi

Electrical and Computer Engineering Faculty Research & Creative Works

High-frequency currents on the pins of integrated circuits (ICs) and on printed circuit board (PCB) traces are needed to predict and analyze electromagnetic interference in high-speed devices. These currents can, however, be difficult to measure when traces are buried within the PCB or chip-package, especially when several current-carrying traces are in close proximity. Techniques for estimating high-frequency currents from near-field scan data are proposed in this paper. These techniques are applied to find currents on the pins of an IC, on traces buried beneath other traces in a PCB, and on traces over a slot in the ground plane. Methods …

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Experimental Validation Of An Autonomous Control System On A Mobile Robot Platform, Timothy Mclain, Randall W. Beard, Wei Ran, J.-S. Sun Nov 2007

Experimental Validation Of An Autonomous Control System On A Mobile Robot Platform, Timothy Mclain, Randall W. Beard, Wei Ran, J.-S. Sun

Faculty Publications

An autonomous control system designed for a non-holonomic wheeled mobile robot that is programmed to emulate a fixed-wing unmanned air vehicle (UAV) flying at constant altitude is experimentally validated. The overall system is capable of waypoint navigation, threat avoidance, real-time trajectory generation and trajectory tracking. Both the wheeled mobile robot experimental platform and the hierarchical autonomous control software architecture are introduced. Programmed to emulate a fixed-wing UAV flying at constant altitude, a non-holonomic mobile robot is assigned to follow a desired time-parameterised trajectory generated by a real-time trajectory generator to transition through a sequence of targets in the presence of …

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Corrales Mainstreet: Community Economic Assessment, Jeffrey Mitchell, Molly J. Bleecker, Joshua M. Akers Nov 2007

Corrales Mainstreet: Community Economic Assessment, Jeffrey Mitchell, Molly J. Bleecker, Joshua M. Akers

BBER Publications

An analysis of Corrales, New Mexicos MainStreet business district and local market area. Demographic, housing, and economic characteristics of both areas are described. Pull factors and location quotients are used to analyze the strengths and weaknesses of the MainStreet district. Data for the MainStreet district and the village of Corrales are compared to Sandoval County and the state. Concludes with a discussion of local opportunities and challenges. Illustrated with charts, data tables, and maps.'

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Comparison Of A Low Carbohydrate And Low Fat Diet For Weight Maintenance In Overweight Or Obese Adults Enrolled In A Clinical Weight Management Program, James D. Lecheminant, Cheryl A. Gibson, Debra K. Sullivan, Sandra Hall, Rik Washburn, Mary C. Vernon, Chelsea Curry, Elizabeth Stewart, Eric C. Westman, Joseph E. Donnelly Nov 2007

Comparison Of A Low Carbohydrate And Low Fat Diet For Weight Maintenance In Overweight Or Obese Adults Enrolled In A Clinical Weight Management Program, James D. Lecheminant, Cheryl A. Gibson, Debra K. Sullivan, Sandra Hall, Rik Washburn, Mary C. Vernon, Chelsea Curry, Elizabeth Stewart, Eric C. Westman, Joseph E. Donnelly

Faculty Publications

Background: Recent evidence suggests that a low carbohydrate (LC) diet may be equally or more effective for short-term weight loss than a traditional low fat (LF) diet; however, less is known about how they compare for weight maintenance. The purpose of this study was to compare body weight (BW) for participants in a clinical weight management program, consuming a LC or LF weight maintenance diet for 6 months following weight loss. Methods: Fifty-five (29 low carbohydrate diet; 26 low fat diet) overweight/obese middle-aged adults completed a 9 month weight management program that included instruction for behavior, physical activity (PA), and …

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Vacancy Localization In The Square Dimer Model, Mark Bowick, J. Bouttier, Emmanuel Guitter, Monwhea Jeng Oct 2007

Vacancy Localization In The Square Dimer Model, Mark Bowick, J. Bouttier, Emmanuel Guitter, Monwhea Jeng

Physics - All Scholarship

We study the classical dimer model on a square lattice with a single vacancy by developing a graph-theoretic classification of the set of all configurations which extends the spanning tree formulation of close-packed dimers. With this formalism, we can address the question of the possible motion of the vacancy induced by dimer slidings. We find a probability 57/4-10Sqrt[2] for the vacancy to be strictly jammed in an infinite system. More generally, the size distribution of the domain accessible to the vacancy is characterized by a power law decay with exponent 9/8. On a finite system, the probability that a vacancy …

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The Cord Weekly (October 31, 2007) Oct 2007

The Cord Weekly (October 31, 2007)

The Cord

No abstract provided.

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The Register, 2007-10-31, North Carolina Agricutural And Technical State University Oct 2007

The Register, 2007-10-31, North Carolina Agricutural And Technical State University

NCAT Student Newspapers

No abstract provided.

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Volume 99 Issue 10, Southwestern Oklahoma State University Oct 2007

Volume 99 Issue 10, Southwestern Oklahoma State University

The Southwestern - Archive

No abstract provided.

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