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2003

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Articles 1291 - 1320 of 3876

Full-Text Articles in Physical Sciences and Mathematics

Ladar-Based Detection And Tracking Of Moving Objects From A Ground Vehicle At High Speeds, Chieh-Chih Wang, Charles Thorpe, Arne Suppe Jun 2003

Ladar-Based Detection And Tracking Of Moving Objects From A Ground Vehicle At High Speeds, Chieh-Chih Wang, Charles Thorpe, Arne Suppe

Research Collection School Of Computing and Information Systems

Detection and tracking of moving objects (DATMO) in crowded urban areas from a ground vehicle at high speeds is difficult because of a wide variety of targets and uncertain pose estimation from odometry and GPS/DGPS. In this paper we present a solution of the simultaneous localization and mapping (SLAM) with DATMO problem to accomplish this task using ladar sensors and odometry. With a precise pose estimate and a surrounding map from SLAM, moving objects are detected without a priori knowledge of the targets. The interacting multiple model (IMM) estimation algorithm is used for modeling the motion of a moving object …


Using Support Vector Machines For Terrorism Information Extraction, Aixin Sun, Myo-Myo Naing, Ee Peng Lim, Wai Lam Jun 2003

Using Support Vector Machines For Terrorism Information Extraction, Aixin Sun, Myo-Myo Naing, Ee Peng Lim, Wai Lam

Research Collection School Of Computing and Information Systems

Information extraction (IE) is of great importance in many applications including web intelligence, search engines, text understanding, etc. To extract information from text documents, most IE systems rely on a set of extraction patterns. Each extraction pattern is defined based on the syntactic and/or semantic constraints on the positions of desired entities within natural language sentences. The IE systems also provide a set of pattern templates that determines the kind of syntactic and semantic constraints to be considered. In this paper, we argue that such pattern templates restricts the kind of extraction patterns that can be learned by IE systems. …


Adaptive Filters For Continuous Queries Over Distributed Data Stream, Chris Olston, Jing Jiang, Jennifer Widom Jun 2003

Adaptive Filters For Continuous Queries Over Distributed Data Stream, Chris Olston, Jing Jiang, Jennifer Widom

Research Collection School Of Computing and Information Systems

We consider an environment where distributed data sources continuously stream updates to a centralized processor that monitors continuous queries over the distributed data. Significant communication overhead is incurred in the presence of rapid update streams, and we propose a new technique for reducing the overhead. Users register continuous queries with precision requirements at the central stream processor, which installs filters at remote data sources. The filters adapt to changing conditions to minimize stream rates while guaranteeing that all continuous queries still receive the updates necessary to provide answers of adequate precision at all times. Our approach enables applications to trade …


Measuring Boltzmann's Constant Using Video Microscopy Of Brownian Motion, Paul Nakroshis, Matthew Amoroso, Jason Legere, Christian Smith Jun 2003

Measuring Boltzmann's Constant Using Video Microscopy Of Brownian Motion, Paul Nakroshis, Matthew Amoroso, Jason Legere, Christian Smith

USM Physics Program

Boltzmann's constant k was measured by observing the Brownian motion of polystyrene spheres in water. An inexpensive monochrome CCD camera and video card were used to create a video of the spheres' motion. After preprocessing the images, custom routines were used to examine the video and to identify and track the particles from one frame to the next. From the mean squared displacement of the particles versus time, we extracted the value of k from the slope, assuming that the drag force on an individual sphere is well modeled by Stokes' law.


A Comparison Of Different Schemes For Selecting And Estimating Score Functions Based On Residuals, Ali A. Al-Shomrani Jun 2003

A Comparison Of Different Schemes For Selecting And Estimating Score Functions Based On Residuals, Ali A. Al-Shomrani

Dissertations

In a linear model when the errors follow a normal distribution, least squares methodology is most powerful. However, when the assumption of normality of the error distribution is not met then there exist methods which are more powerful than least squares methods. Rank-based methods form one such class. These methods depend on the selection of a score function [varphi]( u ). The correct choice of [varphi] leads to an optimal (efficient) analysis, but its selection depends on the error distribution which is not known.

In this thesis, we explore different schemes for score selection. Some of these schemes are functions …


Comparative Study Of Embedding Methods, C. J. Cellucci, Alfonso M. Albano, P. E. Rapp Jun 2003

Comparative Study Of Embedding Methods, C. J. Cellucci, Alfonso M. Albano, P. E. Rapp

Physics Faculty Research and Scholarship

Embedding experimental data is a common first step in many forms of dynamical analysis. The choice of appropriate embedding parameters (dimension and lag) is crucial to the success of the subsequent analysis. We argue here that the optimal embedding of a time series cannot be determined by criteria based solely on the time series itself. Therefore we base our analysis on an examination of systems that have explicit analytic representations. A comparison of analytically obtained results with those obtained by an examination of the corresponding time series provides a means of assessing the comparative success of different embedding criteria. The …


Comment On "Performance Of Different Synchronization Measures In Real Data: A Case Study On Electroencephalographic Signals", R. B. Duckrow, Alfonso M. Albano Jun 2003

Comment On "Performance Of Different Synchronization Measures In Real Data: A Case Study On Electroencephalographic Signals", R. B. Duckrow, Alfonso M. Albano

Physics Faculty Research and Scholarship

Quian Quiroga [Phys. Rev. E 65, 041903 (2002)] reported a similar performance of several linear and nonlinear measures of synchronization when applied to the rat electrocorticogram (ECoG). However, they found that the mutual information measure did not produce robust estimates of synchronization when compared to other measures. We reexamined their data using a histogram method with adaptive partitioning and found the mutual information to be a useful measure of regional ECoG interdependence.


City Of Virginia Beach Dune Inventory, C. Scott Hardaway Jr., Donna A. Milligan, Lyle M. Varnell, George R. Thomas, Walter L. Priest, Linda M. Meneghini, Thomas A. Barnard, Sharon A. Killeen Jun 2003

City Of Virginia Beach Dune Inventory, C. Scott Hardaway Jr., Donna A. Milligan, Lyle M. Varnell, George R. Thomas, Walter L. Priest, Linda M. Meneghini, Thomas A. Barnard, Sharon A. Killeen

Reports

The City of Virginia Beach is located on the southern shore of Chesapeake Bay (Figure 1). Ocean coast dunes were not included in this assessment. Primary tidal shorelines extend from Cape Henry westward to Little Creek Inlet. Eight (8) dune sites were identified along the City of Virginia Beach shoreline on the southern shore of Chesapeake Bay (Figure 2). It is the intent of this publication to provide the user with information on the status of dunes in City of Virginia Beach. This information comes from research performed in 1999 and 2000 which was presented in a report entitled “Chesapeake …


Stratigraphy Of Lake Michigan Lobe Deposits In Van Buren County, Michigan, Steven P. Beukema Jun 2003

Stratigraphy Of Lake Michigan Lobe Deposits In Van Buren County, Michigan, Steven P. Beukema

Masters Theses

The surficial glacial deposits and landforms of Van Buren County were recently mapped at a 1:24,000 scale as part of a STATEMAP project. Several borings were drilled to supplement the surface data. Six of these borings were characterized in detail by means of gamma ray logging, textural analysis, and X-ray diffraction of the clay-sized fraction of the diamicton units.

Results from this study reveal two diamicton units at stratigraphically distinct positions that can be correlated across the county and that are separated by a thick sequence of lacustrine sediments. Correlation of diamicton and lacustrine units was accomplished by analyzing several …


Investigating The Geoelectrical Response Of Hydrocarbon Contamination Undergoing Biodegradation, D. Dale Werkema, Estella A. Atekwana, Anthony L. Endres, William August Sauck, Daniel P. Cassidy Jun 2003

Investigating The Geoelectrical Response Of Hydrocarbon Contamination Undergoing Biodegradation, D. Dale Werkema, Estella A. Atekwana, Anthony L. Endres, William August Sauck, Daniel P. Cassidy

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A newly proposed geoelectrical model for hydrocarbon contaminated sites predicts high conductivities coincident with the contaminated zone as opposed to the traditionally accepted low conductivity. The model attributes the high conductivities to mineral weathering resulting from byproducts of microbial redox processes. To evaluate this conductive model, in situ vertical conductivity measurements were acquired from a light non-aqueous phase liquid (LNAPL) contaminated site. The results showed high conductivities coincident with the zone of contamination and within the smear zone influenced by seasonal water table fluctuations. We infer this zone as an active zone of biodegradation and suggest significant microbial degradation under …


A 59-Cobalt Nmr Investigation Of The Hydrogen/Deuterium Exchange Kinetics In Cobalt(Iii) Complexes, Michelle Mccombs Jun 2003

A 59-Cobalt Nmr Investigation Of The Hydrogen/Deuterium Exchange Kinetics In Cobalt(Iii) Complexes, Michelle Mccombs

Masters Theses & Specialist Projects

Currently, the hydrogen/deuterium exchange kinetics in cobalt(III) complexes are being investigated. In the presence of deuterated solvents, (e.g. D2 0 and CH3CH20D) the amine hydrogens in the complexes are exchanged for deuteriums. For the hexaamminecobalt(III) ion, 19 isotopmers (H18D0 to HOD 18) are possible. For the tris(ethylenediammine)cobalt(III) ion, 13 isotopmers (HI 2D0 to HOD 12) are possible. Each hydrogen/deuteruim exchange causes a shift in the observed 59Co resonance of approximately 6 ppm. The rate constant of the hydrogen-deuterium exchange for the first H-D exchange has been determined as a function of solvent. When the chosen solvent is D20, the rate …


Strategyproof Mechanisms For Ad Hoc Network Formation, C. Jason Woodard, David C. Parkes Jun 2003

Strategyproof Mechanisms For Ad Hoc Network Formation, C. Jason Woodard, David C. Parkes

Research Collection School Of Computing and Information Systems

Agents in a peer-to-peer system typically have incentives to influence its network structure, either to reduce their costs or increase their ability to capture value. The problem is compounded when agents can join and leave the system dynamically. This paper proposes three economic mechanisms that offset the incentives for strategic behavior and facilitate the formation of networks with desirable global properties.


Evaluating Recruitment Of American Eel, Anguilla Rostrata, To The Potomac River Spring 2003, Marcel M. Montane, M. Todd Mathes, Hank Brooks Jun 2003

Evaluating Recruitment Of American Eel, Anguilla Rostrata, To The Potomac River Spring 2003, Marcel M. Montane, M. Todd Mathes, Hank Brooks

Reports

The Atlantic States Marine Fisheries Commission (ASMFC) adopted the Interstate Fishery Management Plan (FMP) for the American eel in November 1999. The FMP focuses on increasing the states’ efforts to collect data on the resource and the fishery it supports through both fishery dependent and fishery independent studies. To this end, member jurisdictions (including the PRFC) agreed to implement an annual abundance survey for young of year (YOY) American eels. The survey is intended to “…characterize trends in annual recruitment of young of year eels over time [to produce a] qualitative appraisal of the annual recruitment of American eel to …


Integrated Coastal Management & Sustainable Aquaculture Development In The Adriatic Sea, Republic Of Croatia, Anamarija Frankic Jun 2003

Integrated Coastal Management & Sustainable Aquaculture Development In The Adriatic Sea, Republic Of Croatia, Anamarija Frankic

Reports

This report discusses development of responsible aquaculture in the Republic of Croatia as part of the integrated coastal zone management and sustainable development of marine, coastal and islands natural and human resources. Based on literature review examples of aquaculture development and its constraints are presented, as well as possible solutions and recommendations. In addition, one attachment document provides brief summary information regarding Mediterranean lessons in aquaculture practices, while second document provides draft guidelines for sustainable aquaculture development in Croatia. Report is a contribution to the project ‘The Integrated Coastal Zone Management for Croatia with special focus on aquaculture’, administered by …


Modeling Product Development As A System Design Game, C. Jason Woodard Jun 2003

Modeling Product Development As A System Design Game, C. Jason Woodard

Research Collection School Of Computing and Information Systems

A system design game is a model of a situation in which agents’ actions determine the structure of a system, which in turn affects the system’s value and the share of value that each agent may capture through bargaining or market competition. This paper describes a class of games in which agents design interdependent products, for example software programs, which may be complements or substitutes for each other. These relationships are epresented by an object called a design structure network (DSN). Depending on the modeler’s choice of allocation rules, agents may benefit from owning critical nodes in the DSN, corresponding …


Cultural And Psychological Influences On Diabetic Adherence, Keikilani Mcmillin-Williams Jun 2003

Cultural And Psychological Influences On Diabetic Adherence, Keikilani Mcmillin-Williams

Loma Linda University Electronic Theses, Dissertations & Projects

Diabetes mellitus is a serious disease that poses a particular healthcare challenge because progression is considered controllable (Cox, et al, 1985; Vinicor, et al, 1996) yet treatment adherence, and thus outcome, is very poor (Gonder-Frederick, Cox, & Ritterband, 2002; Goodall, 1991). Culture is a lethal risk factor for diabetic contraction and treatment maintenance. Latinos within the United States are two-to-three times more likely to develop complications and die than non-Latinos (Haffner et al, 1996; Rubin, Peyrot, & Saudek, 1991) and are less likely to adhere to treatment (Lipton, Losey, Giachello, Mendez, & Girotti, 1998). Efforts to eliminate health disparities have …


The Effect Of Ultrasonics On Fibroblast Cells, Sheila A. Harris Jun 2003

The Effect Of Ultrasonics On Fibroblast Cells, Sheila A. Harris

Loma Linda University Electronic Theses, Dissertations & Projects

The field of dentistry uses the debriding properties of ultrasonic vibration. It is unknown if this property is detrimental to the periodontal ligament (PDL) of an avulsed tooth. This information is important when a clinician is faced with a debris-covered avulsed tooth following a traumatic event. The purpose of this study was to determine the effect that ultrasonic vibration has on those PDL cells most numerous and most vital to a successful tooth replantation, namely, the fibroblasts.

Several fibroblast cell sources were exposed to varying ultrasonic times. These included a commercially available cell line of human foreskin fibroblast (HFF), a …


The Kerf Toolkit For Intrusion Analysis (Poster Abstract), Javed Aslam, Sergey Bratus, David Kotz, Ron Peterson, Daniela Rus, Brett Tofel Jun 2003

The Kerf Toolkit For Intrusion Analysis (Poster Abstract), Javed Aslam, Sergey Bratus, David Kotz, Ron Peterson, Daniela Rus, Brett Tofel

Dartmouth Scholarship

We consider the problem of intrusion analysis and present the Kerf toolkit, whose purpose is to provide an efficient and flexible infrastructure for the analysis of attacks. The Kerf toolkit includes a mechanism for securely recording host and network logging information for a network of workstations, a domain-specific language for querying this stored data, and an interface for viewing the results of such a query, providing feedback on these results, and generating new queries in an iterative fashion. We describe the architecture of Kerf in detail, present examples to demonstrate the power of our query language, and discuss the performance …


Tools For The Automatic Identification And Classification Of Rna Base Pairs, Neocles B. Leontis, Huanwang Yang, Fabrice Jossinet, Li Chen, John Westbrook, Helen Berman, Eric Westhof Jun 2003

Tools For The Automatic Identification And Classification Of Rna Base Pairs, Neocles B. Leontis, Huanwang Yang, Fabrice Jossinet, Li Chen, John Westbrook, Helen Berman, Eric Westhof

Chemistry Faculty Publications

Three programs have been developed to aid in the classification and visualization of RNA structure. BPViewer provides a web interface for displaying three-dimensional (3D) coordinates of individual base pairs or base pair collections. A web server, RNAview, automatically identifies and classifies the types of base pairs that are formed in nucleic acid structures by various combinations of the three edges, Watson-Crick, Hoogsteen and the Sugar edge. RNAView produces two-dimensional (2D) diagrams of secondary and tertiary structure in either Postscript, VRML or RNAML formats. The application RNAMLview can be used to rearrange various parts of the RNAView 2D diagram to generate …


Non-Watson-Crick Basepairing And Hydration In Rna Motifs: Molecular Dynamics Of 5s Rrna Loop E, Neocles B. Leontis, Kamila Réblová, Nad'a Špačková, Richard Štefl, Kristina Csaszar, Jaroslav Koča, J Sponer Jun 2003

Non-Watson-Crick Basepairing And Hydration In Rna Motifs: Molecular Dynamics Of 5s Rrna Loop E, Neocles B. Leontis, Kamila Réblová, Nad'a Špačková, Richard Štefl, Kristina Csaszar, Jaroslav Koča, J Sponer

Chemistry Faculty Publications

Explicit solvent and counterion molecular dynamics simulations have been carried out for a total of > 80 ns on the bacterial and spinach chloroplast 5S rRNA Loop E motifs. The Loop E sequences form unique duplex architectures composed of seven consecutive non-Watson-Crick basepairs. The starting structure of spinach chloroplast Loop E was modeled using isostericity principles, and the simulations refined the geometries of the three non-Watson-Crick basepairs that differ from the consensus bacterial sequence. The deep groove of Loop E motifs provides unique sites for cation binding. Binding of Mg2+ rigidifies Loop E and stabilizes its major groove at an intermediate …


Pole Assignment For A Vibrating System With Aerodynamic Effect, J. N. Wang, So-Hsiang Chou, Y. C. Chen, W. W. Lin Jun 2003

Pole Assignment For A Vibrating System With Aerodynamic Effect, J. N. Wang, So-Hsiang Chou, Y. C. Chen, W. W. Lin

Mathematics and Statistics Faculty Publications

This paper deals with a pole assignment problem by single-input state feedback control arising from a one-dimensional vibrating system with aerodynamic effect. On the practical side, we derive explicit formulae for the required controlling force terms, which can reassign part of the spectrum to the desired values while leaving the remaining spectrum unchanged. On the mathematical side, unlike the classical Sturm–Liouville problem, our eigenvalue problem is associated with a cubic pencil with unbounded operators as coefficients and has many interesting new features, one of which is that a new controllability condition appears. This condition together with the known controllability condition …


Morphological Biosignatures And The Search For Life On Mars, Sherry L. Cady, Jack D. Farmer, John P. Grotzinger, J. William Schopf, Andrew Steele Jun 2003

Morphological Biosignatures And The Search For Life On Mars, Sherry L. Cady, Jack D. Farmer, John P. Grotzinger, J. William Schopf, Andrew Steele

Geology Faculty Publications and Presentations

This report provides a rationale for the advances in instrumentation and understanding needed to assess claims of ancient and extraterrestrial life made on the basis of morphological biosignatures. Morphological biosignatures consist of bona fide microbial fossils as well as microbially influenced sedimentary structures. To be recognized as evidence of life, microbial fossils must contain chemical and structural attributes uniquely indicative of microbial cells or cellular or extracellular processes. When combined with various research strategies, high-resolution instruments can reveal such attributes and elucidate how morphological fossils form and become altered, thereby improving the ability to recognize them in the geological record …


Wind Gusts, Christopher Roman May 2003

Wind Gusts, Christopher Roman

Christopher N. Roman

Article that appeared in Sail magazine (ISSN: 0036-2700).


Prediction Of Organic Droplets On Solid Surfaces In Aqueous Surfactant Solutions, Samuel Morton, R. Counce, D. Keffer, D. Depaoli, M. Hu May 2003

Prediction Of Organic Droplets On Solid Surfaces In Aqueous Surfactant Solutions, Samuel Morton, R. Counce, D. Keffer, D. Depaoli, M. Hu

Samuel A Morton

No abstract provided.


An Architecture For Building Web Service Applications, Jia Zhang, Jen-Yao Chung May 2003

An Architecture For Building Web Service Applications, Jia Zhang, Jen-Yao Chung

Jia Zhang

No abstract provided.


A Model For Shear Stress Sensing And Transmission In Vascular Endothelial Cells, Borbala Mazzag, John S. Tamaresis, Abdul Barakat May 2003

A Model For Shear Stress Sensing And Transmission In Vascular Endothelial Cells, Borbala Mazzag, John S. Tamaresis, Abdul Barakat

Borbala Mazzag

 Arterial endothelial cell (EC) responsiveness to flow is essential for normal vascular function and plays a role in the development of atherosclerosis. EC flow responses may involve sensing of the mechanical stimulus at the cell surface with subsequent transmission via cytoskeleton to intracellular transduction sites. We had previously modeled flow-induced deformation of EC-surface flow sensors represented as viscoelastic materials with standard linear solid behavior (Kelvin bodies). In the present article, we extend the analysis to arbitrary networks of viscoelastic structures connected in series and/or parallel. Application of the model to a system of two Kelvin bodies in parallel reveals that …


Femtosecond Phase-Coherent Two-Dimensional Spectroscopy, Peifang Tian, Dorine Keusters, Yoshifumi Suzaki, Warren S. Warren May 2003

Femtosecond Phase-Coherent Two-Dimensional Spectroscopy, Peifang Tian, Dorine Keusters, Yoshifumi Suzaki, Warren S. Warren

Peifang Tian

Femtosecond phase-coherent two-dimensional (2D) spectroscopy has been experimentally demonstrated as the direct optical analog of 2D nuclear magnetic resonance. An acousto-optic pulse shaper created a collinear three-pulse sequence with well-controlled and variable interpulse delays and phases, which interacted with a model atomic system of rubidium vapor. The desired nonlinear polarization was selected by phase cycling (coadding experimental results obtained with different interpulse phases). This method may enhance our ability to probe the femtosecond structural dynamics of macromolecules.


Image Morphological Processing, Vijayalakshmi Gaddipati May 2003

Image Morphological Processing, Vijayalakshmi Gaddipati

Dissertations

Mathematical Morphology with applications in image processing and analysis has been becoming increasingly important in today's technology. Mathematical Morphological operations, which are based on set theory, can extract object features by suitably shaped structuring elements. Mathematical Morphological filters are combinations of morphological operations that transform an image into a quantitative description of its geometrical structure based on structuring elements. Important applications of morphological operations are shape description, shape recognition, nonlinear filtering, industrial parts inspection, and medical image processing.

In this dissertation, basic morphological operations, properties and fuzzy morphology are reviewed. Existing techniques for solving corner and edge detection are presented. …


Fully Nonlinear Interfacial Waves In A Bounded Two-Fluid System, Lyudmyla Leonidivna Barannyk May 2003

Fully Nonlinear Interfacial Waves In A Bounded Two-Fluid System, Lyudmyla Leonidivna Barannyk

Dissertations

We study the nonlinear flow which results when two immiscible inviscid incompressible fluids of different densities and separated by an interface which is free to move and which supports surface tension, are caused to flow in a straight infinite channel. Gravity is taken into consideration and the velocities of each phase can be different, thus giving rise to the Kelvin-Helmholtz instability. Our objective is to study the competing effects of the Kelvin-Helmholtz instability coupled with a stably or unstably stratified fluid system (Rayleigh-Taylor instability) when surface tension is present to regularize the dynamics. Our approach involves the derivation of two-and …


Optimization For Source Localization And Geoacoustic Inversion In Underwater Acoustics, Urmi Ghosh-Dastidar May 2003

Optimization For Source Localization And Geoacoustic Inversion In Underwater Acoustics, Urmi Ghosh-Dastidar

Dissertations

Matched-field inversion techniques are widely used for source localization and geoacoustic parameter estimation. These inversion methods correlate the received data with modeled data and find the model parameters which provide the maximum correlation. However, when a large number of unknown parameters is involved, many modeled data need to be generated and correlated with the observed data and thus, matched-field inversion can be computationally intensive. An optimization process applied to matched-field inversion is often required to accelerate the inversion process.

In this work, tabu is applied to matched-field inversion for source localization and environmental parameter estimation. Tabu is a global optimization …