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2002

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Articles 2551 - 2580 of 3435

Full-Text Articles in Physical Sciences and Mathematics

Managing Semantic Content For The Web, Amit P. Sheth, Clemens Bertram, David Avant, Brian Hammond, Krzysztof Kochut, Yashodhan Warke Jan 2002

Managing Semantic Content For The Web, Amit P. Sheth, Clemens Bertram, David Avant, Brian Hammond, Krzysztof Kochut, Yashodhan Warke

Kno.e.sis Publications

By associating meaning with content, the Semantic Web will facilitate search, interoperability, and the composition of complex applications. A recent Scientific American article described the Semantic Web as 'an extension of the current Web in which information is given well-defined meaning, better enabling computers and people to work in cooperation.' Not long ago, researchers at a Stanford University symposium predicted that this second phase of the Web would be as revolutionary as the Web itself.


Authorization And Access Control Of Application Data In Workflow Systems, Shengli Wu, Amit P. Sheth, John A. Miller, Zongwei Luo Jan 2002

Authorization And Access Control Of Application Data In Workflow Systems, Shengli Wu, Amit P. Sheth, John A. Miller, Zongwei Luo

Kno.e.sis Publications

Workflow Management Systems (WfMSs) are used to support the modeling and coordinated execution of business processes within an organization or across organizational boundaries. Although some research efforts have addressed requirements for authorization and access control for workflow systems, little attention has been paid to the requirements as they apply to application data accessed or managed by WfMSs. In this paper, we discuss key access control requirements for application data in workflow applications using examples from the healthcare domain, introduce a classification of application data used in workflow systems by analyzing their sources, and then propose a comprehensive data authorization and …


2002-2003 Nova Southeastern University Farquhar Center For Undergraduate Studies Catalog, Nova Southeastern University Jan 2002

2002-2003 Nova Southeastern University Farquhar Center For Undergraduate Studies Catalog, Nova Southeastern University

Undergraduate Programs Course Catalogs

No abstract provided.


Software And Hardware Methods For Memory Access Latency Reduction On Ilp Processors, Zhao Zhang Jan 2002

Software And Hardware Methods For Memory Access Latency Reduction On Ilp Processors, Zhao Zhang

Dissertations, Theses, and Masters Projects

While microprocessors have doubled their speed every 18 months, performance improvement of memory systems has continued to lag behind. to address the speed gap between CPU and memory, a standard multi-level caching organization has been built for fast data accesses before the data have to be accessed in DRAM core. The existence of these caches in a computer system, such as L1, L2, L3, and DRAM row buffers, does not mean that data locality will be automatically exploited. The effective use of the memory hierarchy mainly depends on how data are allocated and how memory accesses are scheduled. In this …


Racks, Quandles And Virtual Knots, Victor Samuel Nelson Jan 2002

Racks, Quandles And Virtual Knots, Victor Samuel Nelson

LSU Doctoral Dissertations

We begin with a brief survey of the theory of virtual knots, which was announced in 1996 by Kauffman. This leads naturally to the subject of quandles and quandle homology, which we also briefly introduce. Chapter 2 contains a proof in terms of Gauss diagrams that the forbidden moves unknot virtual knots. This chapter includes material which has appeared in the Journal of Knot Theory and its Ramifications and is reprinted here by permission of World Scientific Publishing. In chapter 3 (cowritten with my advisor R.A.Litherland) we confirm a conjecture of J.S.Carter et.al. that the long exact sequence in rack …


Molecular Dynamics Simulations Of Adhesion And Nanoidentation Of Gallium Arsenide, Francis Brent Neal, Jr. Jan 2002

Molecular Dynamics Simulations Of Adhesion And Nanoidentation Of Gallium Arsenide, Francis Brent Neal, Jr.

LSU Doctoral Dissertations

The purpose of this dissertation is to investigate the nanoscale hardness of gallium arsenide thin films and the elastic-plastic behavior of gallium arsenide under an indenter. These investigations were carried out using molecular dynamics (MD) simulations. The simulations are based on interatomic potentials that accurately reproduce many properties of bulk GaAs. The MD simulations performed required scalable and efficient algorithms for implementation on large parallel computers. Nanoindentation simulations were performed using an ideal indenter that was held rigid during the simulation. To reduce the transient effects due to loading, the traversal of the indenter was interrupted periodically to allow the …


Nonlinear Dynamics In Nuclear Structure, Guergana Stoianova Stoitcheva Jan 2002

Nonlinear Dynamics In Nuclear Structure, Guergana Stoianova Stoitcheva

LSU Doctoral Dissertations

New collective coordinates that describe the deformation of atomic nuclei in terms of solitary waves (rotons) that are solutions of an underlying nonlinear liquid drop dynamics are introduced. The rotons, which are highly localized surface excitations, are shown to be intelligent states of an underlying angular momentum algebra, and furthermore, to adiabatically decouple from the rotational motion of the nucleus. An expansion of the roton profile in terms of surface multipoles shows that although the quadrupole mode (&lambda= 2) dominates, there are significant contributions from other even multipoles with &lambda= 4, 6, 8, etc. The picture of nuclear deformation that …


The Ligase Detection Reaction: The Evolution Of A Mutation Detection Strategy, Hannah D. Farquar Jan 2002

The Ligase Detection Reaction: The Evolution Of A Mutation Detection Strategy, Hannah D. Farquar

LSU Doctoral Dissertations

Early detection of genetic mutations is important for control of diseases such as cancer and Alzheimer's. Early detection requires methods that detect small amounts of mutated DNA in very large amounts of normal or wild type DNA. One method to detect mutated DNA is the ligase detection reaction (LDR). Since its inception LDR has evolved greatly from a simple detection reaction after PCR amplification to PCR/RE/LDR, a scheme which uses nucleoside base analogs in PCR to convert wild type sequences to sequences containing restriction endonuclease (RE) sites which can then be cleaved leaving only mutant sequences for detection by LDR. …


Water Discharge Models, Seasonal Effluent Mass Loading, And Best Management Practices For Crawfish Ponds, Landon David Parr Jan 2002

Water Discharge Models, Seasonal Effluent Mass Loading, And Best Management Practices For Crawfish Ponds, Landon David Parr

LSU Master's Theses

Nearly 35,000 ha are used to grow crawfish in southwest and south-central Louisiana, and many of these ponds discharge into impaired water bodies. In 2002, proposed guidelines were published by the United States Environmental Protection Agency (USEPA) assigning effluent limitations and standards for some aquaculture production systems and exempting others (e.g. crawfish ponds). This research had three objectives relative to crawfish ponds: develop water discharge models; final drawdown effluent quality and seasonal mass loading of solids and nutrients; and identification of Best Management Practices (BMPs) that could reduce effluent discharge and improve effluent quality. Models for south-central and southwest Louisiana …


Distributed Power Control In Wireless Communication Systems, Sarangapani Jagannathan, A. T. Chronopoulos, S. Ponipireddy Jan 2002

Distributed Power Control In Wireless Communication Systems, Sarangapani Jagannathan, A. T. Chronopoulos, S. Ponipireddy

Electrical and Computer Engineering Faculty Research & Creative Works

Energy efficiency is a measure of performance in wireless networks. Therefore, controlling the transmitter power at a given node increases not only battery operating life, but also overall system capacity by successfully admitting new links. It is essential to find effective means of power control in point-to-point, broadcasting and multicasting scenarios. Wireless networking presents formidable challenges, and we consider the problem of unicast or point-to-point (peer-to-peer) communication in wireless networks in the presence of other nodes. We study the feasibility of admitting new links in an wireless network operating area while maintaining quality of service (QoS), in terms of signal-to-interference …


A Hybrid System Theoretic Approach For Admission Controller Design In Multimedia Networks, Sarangapani Jagannathan Jan 2002

A Hybrid System Theoretic Approach For Admission Controller Design In Multimedia Networks, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

A novel real-time discrete-event admission control (AC) scheme for high-speed networks is proposed with the aim of attaining a desired quality of service (QoS) and high network utilization. The AC uses the available capacity from a novel adaptive bandwidth estimation scheme, a congestion indicator derived from a congestion controller, peak bit/cell rate (PBR/PCR) estimate from new sources, along with the desired QoS metrics, and makes decisions whether to 'admit' or 'reject' new sources. The novel aspect of the proposed approach is the application of hybrid system theory to prove the performance of the admission controller, stability and the development of …


Adaptive Critic-Based Neural Network Controller For Uncertain Nonlinear Systems With Unknown Deadzones, Pingan He, Jagannathan Sarangapani, S. N. Balakrishnan Jan 2002

Adaptive Critic-Based Neural Network Controller For Uncertain Nonlinear Systems With Unknown Deadzones, Pingan He, Jagannathan Sarangapani, S. N. Balakrishnan

Electrical and Computer Engineering Faculty Research & Creative Works

A multilayer neural network (NN) controller in discrete-time is designed to deliver a desired tracking performance for a class of nonlinear systems with input deadzones. This multilayer NN controller has an adaptive critic NN architecture with two NNs for compensating the deadzone nonlinearity and a third NN for approximating the dynamics of the nonlinear system. A reinforcement learning scheme in discrete-time is proposed for the adaptive critic NN deadzone compensator, where the learning is performed based on a certain performance measure, which is supplied from a critic. The adaptive generating NN rejects the errors induced by the deadzone whereas a …


Quantitative Analysis Of Transmission Power Control In Wireless Ad-Hoc Networks, Seung Jong Park, R. Sivakumar Jan 2002

Quantitative Analysis Of Transmission Power Control In Wireless Ad-Hoc Networks, Seung Jong Park, R. Sivakumar

Computer Science Faculty Research & Creative Works

In this paper, we address the issue of transmission power control in wireless ad-hoc networks. In general, it is assumed that the minimum transmission power required to keep the network connected achieves the optimal throughput performance in an ad-hoc network. In contrast, we show that using the minimal transmission range might not always result in optimal throughput performance. Using both throughput and throughput per unit energy as the optimization criteria, we demonstrate that the optimal transmission power is generically a function of the number of stations, the network size, and the traffic load. In particular, we observe that the optimal …


Node Splitting Algorithms In Tree-Structured High-Dimensional Indexes For Similarity Search, Yongjian Fu, Jui Che Teng, S. R. Subramanya Jan 2002

Node Splitting Algorithms In Tree-Structured High-Dimensional Indexes For Similarity Search, Yongjian Fu, Jui Che Teng, S. R. Subramanya

Computer Science Faculty Research & Creative Works

Content-based searches and retrievals in multimedia and image databases use high-dimensional indexing structures for organizing the features of the objects. Most of those index structures are tree-structured whose nodes have a limit on the number of entries describing the subtrees rooted at those nodes. When index trees are built by repeated insertion of entries, nodes need to be split and the tree balanced accordingly. Node-splitting algorithms eventually determine the final structure of the tree which will have a profound effect on the search performance. This paper presents a comparative study of several node splitting algorithms for a typical high-dimensional indexing …


Fabricating Microfluidic Devices In Polymers For Bioanalytica Applications, Sean M. Ford Jan 2002

Fabricating Microfluidic Devices In Polymers For Bioanalytica Applications, Sean M. Ford

LSU Doctoral Dissertations

The research presented in this document focuses on the fabrication, characterization and application of microfluidic systems fabricated in poly(methyl methacrylate) (PMMA) with the emphasis focused on the fabrication processing steps. Microfluidic devices were produced in PMMA using X-ray lithography. The fabrication methods investigated were sacrificial mask, polyimide membrane mask and embossing techniques. PMMA microfluidic devices fabricated using X-ray lithography were characterized using scanning electron microscopy (SEM) and optical microscopy, while analytical techniques such as electroosmotic flow determination, separations, and fluorescent microscopy were used to characterize fluid transport in these devices. A novel method for the heat annealing of PMMA to …


The Synthesis Of New Biotin Derivatives And Their Bioactivity, Latisha Chanette Johnson Jan 2002

The Synthesis Of New Biotin Derivatives And Their Bioactivity, Latisha Chanette Johnson

LSU Master's Theses

Biotin is an essential growth factor found in all living cells. It functions as a cofactor for a group of coenzymes that catalyze transcarboxylation, decarboxylation, and carboxylation reactions. Acetyl CoA carboxylase catalyzes the first committed and regulated step in fatty acid synthesis in which malonyl CoA is the product. The biotin-dependent enzyme is found in all animals, plants, and bacteria. We studied the kinetic and structural aspects of acetyl CoA carboxylase, and in 1999 we reported the bioactivity and total synthesis of a unique first generation biotin-derived inhibitor of acetyl CoA carboxylase, 1(BP1). Kinetic studies on the activity of E. …


Discrete Mathematics Topics In The Secondary School Curriculum, Aimee Beth Boyd Jan 2002

Discrete Mathematics Topics In The Secondary School Curriculum, Aimee Beth Boyd

LSU Master's Theses

This thesis discusses two topics of discrete mathematics in a manner suitable for presentation at a secondary-school level. The introduction outlines the benefits of including discrete mathematics in the secondary-school curriculum. The two chapters which follow include detailed treatment of the two selected topics: the Traveling Salesman Problem and RSA encryption. The discussion of the Traveling Salesman Problem consists of introduction to the problem through several real-life scenarios, followed by a discussion of various methods for solving the problem. We discuss exact and approximate algorithms together with their computational complexity and practical limitations. The discussion of RSA encryption begins with …


Characterization Of An In Vivo Diode Dosimetry System For Clinical Use, Kai Huang Jan 2002

Characterization Of An In Vivo Diode Dosimetry System For Clinical Use, Kai Huang

LSU Master's Theses

An in vivo dosimetry system that uses p-type semiconductor diodes with buildup caps was characterized for clinical use. The dose per pulse dependence was investigated. This was done by altering the SSD, field size and wedge for photons, and by altering SSD and cone size for electrons. The off-axis correction and effect of changing repetition rate were also investigated. A model was made to fit the measured diode correction factors.


Denitrification Potential Of Sediment From A Future Mississippi River Diversion Site In Louisiana, Roy Ryuta Iwai Jan 2002

Denitrification Potential Of Sediment From A Future Mississippi River Diversion Site In Louisiana, Roy Ryuta Iwai

LSU Master's Theses

Denitrification potential was determined in surface sediment from Lake Cataouatche, the receiving basin for a future Mississippi River diversion located in the northern portion of the Barataria Basin estuary. Nitrate removal and denitrification was measured in the laboratory using static sediment microcosms flooded with lake water. Dissolved potassium nitrate (KNO3) was added to the microcosms to achieve: 1) an initial nitrate concentration similar to the mean Mississippi River concentration (~1.4 mg NO3-N l-1), and, 2) a high initial nitrate concentration to elicit a denitrification potential (~50 mg NO3-N l-1). Denitrification …


Sedimentology And Stratigraphy Of The Upper Cretaceous-Paleocene El Molino Formation, Eastern Cordillera And Altiplano, Central Andes, Bolivia: Implications For The Tectonic Development Of The Central Andes, Richard John Fink Jan 2002

Sedimentology And Stratigraphy Of The Upper Cretaceous-Paleocene El Molino Formation, Eastern Cordillera And Altiplano, Central Andes, Bolivia: Implications For The Tectonic Development Of The Central Andes, Richard John Fink

LSU Master's Theses

The Upper Cretaceous-Paleocene El Molino Formation of the Bolivian Central Andes consists of mixed siliciclastic and carbonate strata alternately interpreted as syn-rift, post-rift thermal sag and foreland basin deposits. These deposits can be divided into two lithostratigraphic sequences. The first sequence consists of a carbonate, carbonate sand and mudrock lower member, a middle member consisting entirely of mudrock and an upper member containing carbonates and mudrocks. The second lithostratigraphic sequence contains a lower member composed of carbonate sands, carbonates and mudrocks, and an upper member consisting of a coarsening upwards sequence of sandstones and mudrocks. Within these lithostratigraphic sequences, five …


X-Ray Spectroscopy Of Geometrically Constrained Systems, Edward Earl Doomes Jan 2002

X-Ray Spectroscopy Of Geometrically Constrained Systems, Edward Earl Doomes

LSU Doctoral Dissertations

Hard X-rays (2 KeV or greater) are used as spectroscopic tools in the characterization of chemical systems. X-ray absorption near edge structure (XANES) spectroscopy is used to characterize multiple groups of chemicals in a systematic fashion. This thesis focuses on chemical systems that in some context have geometrical constraints on their structure. They include self-assembled n-alkanethiol monolayers that are tethered to silver substrates, cyclic sulfides, and (Bis(diphenylphosphino) alkane tetracarbonyl metal complexes. The study of n-alkanethiol monolayers on Ag(111) contains the first observation in the literature of an anomalous resonance in the 18 carbon monolayer. A new interpretation of a subthreshold …


Branch, Crown, Tree And Stand Water Flux In An 180-Year-Old Loblolly Pine Plantation After Thinning, Fertilization, And Throughfall Exclusion Treatments, Shufang Yu Jan 2002

Branch, Crown, Tree And Stand Water Flux In An 180-Year-Old Loblolly Pine Plantation After Thinning, Fertilization, And Throughfall Exclusion Treatments, Shufang Yu

LSU Doctoral Dissertations

Branch and tree sap flux density (SFD) was measured to evaluate the effects of thinning, fertilization, and throughfall exclusion treatments on water use by loblolly pine (Pinus taeda L.) trees. Variations in SFD at different radial xylem depths were also examined to improve estimates of tree water use from sap flux density measured in the outer sapwood. This study was conducted in an 18-year-old loblolly pine plantation in central Louisiana in 1999. The results revealed that SFD was higher in the outer xylem than in the inner xylem and large trees had higher SFD than small trees. Thinning increased daily …


Significance Of Variations Among Ancient Deltaic Deposits In The Arkoma Basin, North-Central Arkansas, Christine Michelle Wright Jan 2002

Significance Of Variations Among Ancient Deltaic Deposits In The Arkoma Basin, North-Central Arkansas, Christine Michelle Wright

LSU Master's Theses

The Arkoma Basin is one of several foreland basins formed in association with the Ouachita orogeny. The Arkoma Basin has been studied in depth with regard to stratigraphy, depositional environments, structure and its relationship to the Appalachian-Ouachita orogenic event. This study focuses on the variability of the deltaic deposits within the Arkoma Basin and the significance of the variables to both the delta complex and the overall tectonic setting. The specific characteristics to be investigated include variations in paleocurrent directions, bed thicknesses, bed geometries, organic contents, sand/shale ratios, mineral assemblages and fossil assemblages. In the case of the Arkoma deltaic …


Synthetic, Structural, Magnetic, And Mössbauer Spectral Study Of {Fe[Hc(3,5-Me2pz)3]2}I2 And Its Spin-State Crossover Behavior, Daniel L. Reger, Christine A. Little, Mark D. Smith, Arnold L. Rheingold, Kin Chung Lam, Thomas L. Concolino, Gary J. Long, Raphaël P. Hermann, Fernande Grandjean Jan 2002

Synthetic, Structural, Magnetic, And Mössbauer Spectral Study Of {Fe[Hc(3,5-Me2pz)3]2}I2 And Its Spin-State Crossover Behavior, Daniel L. Reger, Christine A. Little, Mark D. Smith, Arnold L. Rheingold, Kin Chung Lam, Thomas L. Concolino, Gary J. Long, Raphaël P. Hermann, Fernande Grandjean

Chemistry Faculty Research & Creative Works

The complex {Fe [HC(3,5-Me2pz)3]2} I2 (1) has been prepared from the reaction of FeI2 and HC(3,5-Me2pz)3 (pz = pyrazolyl ring) in a 1:2 ratio. The complex is high spin in both the solid state and in solution at ambient temperature. In the solid state, magnetic susceptibility and Mössbauer spectral studies indicate that samples of the complex that have been crystallized and dried change completely from high-spin to low-spin upon cooling below 195 K, with a substantial two-step thermal hysteresis in the transition. The spin-crossover properties of 1 are sample …


Upper Spokane River Model: Model Calibration, 1991 And 2000, Chris Berger, Robert Leslie Annear, Scott A. Wells Jan 2002

Upper Spokane River Model: Model Calibration, 1991 And 2000, Chris Berger, Robert Leslie Annear, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The Washington Department of Ecology is interested in a water quality model for the Upper Spokane River system for use in developing Total Maximum Daily Loads (TMDLs). The goals of this modeling effort are to:

• Gather data to construct a computer simulation model of the Spokane River system including Long Lake Reservoir and the pools behind Nine Mile dam, Upper Falls dam and Upriver dam. • Ensure that the model accurately represents the system hydrodynamics and water quality (flow, temperature, dissolved oxygen and nutrient dynamics)

This report evaluates the model calibration and discusses issues relative to that calibration effort. …


Resource Law Notes Newsletter, No. 53, Winter, Feb. 2002, University Of Colorado Boulder. Natural Resources Law Center Jan 2002

Resource Law Notes Newsletter, No. 53, Winter, Feb. 2002, University Of Colorado Boulder. Natural Resources Law Center

Resource Law Notes: The Newsletter of the Natural Resources Law Center (1984-2002)

No abstract provided.


Towards Nonmonotonic Reasoning On Hierarchical Knowledge, Pascal Hitzler Jan 2002

Towards Nonmonotonic Reasoning On Hierarchical Knowledge, Pascal Hitzler

Computer Science and Engineering Faculty Publications

W.C. Rounds and G.Q. Zhang have recently proposed to study a form of disjunctive logic programming generalized to algebraic domains [RZ01]. This system allows reasoning with information which is hierarchically structured and forms a (suitable) domain. We extend this framework to include reasoning with negative information, i.e. the implicit or explicit absence of bits of information. These investigations will naturally lead to a form of default reasoning which is strongly related to programming with answer sets to stable models, which has recently created much interest amongst artificial intelligence researchers concerned with knowledge representation and reasoning.


The Use Of Dramatic Demonstrations To Enhance The Motivation And Learning Of Chemistry Students, H. A. Rowe Jan 2002

The Use Of Dramatic Demonstrations To Enhance The Motivation And Learning Of Chemistry Students, H. A. Rowe

Journal of Mathematics and Science: Collaborative Explorations

As part of the Virginia Collaborative for Excellence in the Preparation of Teachers (VCEPT) project, a series of demonstrations was incorporated into Chemistry 100: Man and Environment, a science course taken by non-science majors including many prospective K-12 teachers. Dramatic chemical demonstrations were first presented to the undergraduate students by the instructor, and then they used demonstration activities to teach each other during the semester. Finally, these undergraduates presented to the K-6 students in the Norfolk Statue University (NSU) Summer Children’s College. The perceptions of science by the undergraduates at the beginning and end of the course were assessed using …


Predicting Oral Reading Miscues, Jack Mostow, Joseph Beck, S. Vanessa Winter, Shaojun Wang Jan 2002

Predicting Oral Reading Miscues, Jack Mostow, Joseph Beck, S. Vanessa Winter, Shaojun Wang

Kno.e.sis Publications

This paper explores the problem of predicting specific reading mistakes, called miscues, on a given word. Characterizing likely miscues tells an automated reading tutor what to anticipate, detect, and remediate. As training and test data, we use a database of over 100,000 miscues transcribed by University of Colorado researchers. We explore approaches that exploit different sources of predictive power: the uneven distribution of words in text, and the fact that most miscues are real words. We compare the approaches’ ability to predict miscues of other readers on other text. A simple rote method does best on the most frequent 100 …


Multi-Dimensional Regression Analysis Of Time-Series Data Streams, Yixin Chen, Guozhu Dong, Jiawei Han, Benjamin W. Wah, Jianyong Wang Jan 2002

Multi-Dimensional Regression Analysis Of Time-Series Data Streams, Yixin Chen, Guozhu Dong, Jiawei Han, Benjamin W. Wah, Jianyong Wang

Kno.e.sis Publications

Real-time production systems and other dynamic environments often generate tremendous (potentially infinite) amount of stream data; the volume of data is too huge to be stored on disks or scanned multiple times. Can we perform on-line, multi-dimensional analysis and data mining of such data to alert people about dramatic changes of situations and to initiate timely, high-quality responses? This is a challenging task.

In this paper, we investigate methods for online, multi-dimensional regression analysis of time-series stream data, with the following contributions: (1) our analysis shows that only a small number of compressed regression measures instead of the complete stream …