Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

2006

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 3331 - 3360 of 5872

Full-Text Articles in Physical Sciences and Mathematics

The Clock Paradox In A Static Homogeneous Gravitational Field, Preston Jones, Lucas F. Wanex Feb 2006

The Clock Paradox In A Static Homogeneous Gravitational Field, Preston Jones, Lucas F. Wanex

Publications

The gedanken experiment of the clock paradox is solved exactly using the general relativistic equations for a static homogeneous gravitational field. We demonstrate that the general and special relativistic clock paradox solutions are identical and in particular that they are identical for finite acceleration. Practical expressions are obtained for proper time and coordinate time by using the destination distance as the key observable parameter. This solution provides a formal demonstration of the identity between the special and general relativistic clock paradox with finite acceleration and where proper time is assumed to be the same in both formalisms. By solving the …


A Sequence Of Polynomials For Approximating Arctangent, Herbert A. Medina Feb 2006

A Sequence Of Polynomials For Approximating Arctangent, Herbert A. Medina

Mathematics, Statistics and Data Science Faculty Works

No abstract provided.


Free Tools For Teaching & Researching Wireless Networking Concepts, Victor A. Clincy, Krithi Sitaram Ajay Feb 2006

Free Tools For Teaching & Researching Wireless Networking Concepts, Victor A. Clincy, Krithi Sitaram Ajay

Faculty Articles

As wireless networking and security become more prevalent in the market, more and more computer science programs are incorporating courses in wireless networks or at the least, devoting a significant percentage of the advanced networking courses to wireless topics. As a result, in addition to industry practitioners, there is a growing interest among university researchers and faculty regarding tools used for teaching and researching in wireless networking concepts.This tutorial will demonstrate two free tools, Network Stumbler and ITGuru's wireless module (academic version is free).


Path Planning Algorithms Under The Link-Distance Metric, David Phillip Wagner Feb 2006

Path Planning Algorithms Under The Link-Distance Metric, David Phillip Wagner

Dartmouth College Ph.D Dissertations

The Traveling Salesman Problem and the Shortest Path Problem are famous problems in computer science which have been well studied when the objective is measured using the Euclidean distance. Here we examine these geometric problems under a different set of optimization criteria. Rather than considering the total distance traversed by a path, this thesis looks at reducing the number of times a turn is made along that path, or equivalently, at reducing the number of straight lines in the path. Minimizing this objective value, known as the link-distance, is useful in situations where continuing in a given direction is cheap, …


A Modular Onboard Processing System For Small Unmanned Vehicles, Richard D. Garcia Feb 2006

A Modular Onboard Processing System For Small Unmanned Vehicles, Richard D. Garcia

USF Tampa Graduate Theses and Dissertations

This work describes the design and implementation of a generic lightweight onboard processing system for miniature Unmanned Vehicles (UVs) that is computationally powerful and highly adaptable. First, several classical approaches to giant scale and full size UV onboard processing systems are described along with their corresponding limitations. Second, a detailed study is presented that describes the key characteristics of an onboard system along with associated limitations. Next, an implementation of a generic onboard system capable of vision processing and servo based control is presented along with detailed hardware specifications and implementation software. Last, experimental data, both laboratory and field, are …


Fire Properties Of Styrenic Polymer–Clay Nanocomposites Based On An Oligomerically-Modified Clay, Jinguo Zhang, David D. Jiang, Charles A. Wilkie Feb 2006

Fire Properties Of Styrenic Polymer–Clay Nanocomposites Based On An Oligomerically-Modified Clay, Jinguo Zhang, David D. Jiang, Charles A. Wilkie

Chemistry Faculty Research and Publications

An oligomerically-modified clay has been used to fabricate nanocomposites with styrenic polymers, such as polystyrene, high-impacted polystyrene, poly(styrene-co-acrylonitrile) and acrylonitrile–butadiene–styrene by melt blending. The clay dispersion was evaluated by X-ray diffraction and bright field transmission electron microscopy. All of the nanocomposites have a mixed delaminated/intercalated structure. The fire properties of nanocomposites were evaluated by cone calorimetry and the mechanical properties were also evaluated.


Femtosecond Nuclear Motion Of Hcl Probed By Resonant X-Ray Raman Scattering In The Cl 1s Region, Marc Simon, Loic Journel, Stephane Carniato, Richard Taieb, I. Minkov, Faris Gel'mukhanov, P. Salek, H. Agren, Renaud Guillemin, Wayne C. Stolte, A. C. Hudson, Dennis W. Lindle Feb 2006

Femtosecond Nuclear Motion Of Hcl Probed By Resonant X-Ray Raman Scattering In The Cl 1s Region, Marc Simon, Loic Journel, Stephane Carniato, Richard Taieb, I. Minkov, Faris Gel'mukhanov, P. Salek, H. Agren, Renaud Guillemin, Wayne C. Stolte, A. C. Hudson, Dennis W. Lindle

Chemistry and Biochemistry Faculty Research

Femtosecond dynamics are observed by resonant x-ray Raman scattering (RXS) after excitation along the dissociative Cl 1s→6ơ* resonance of gas-phase HCl. The short core-hole lifetime results in a complete breakdown of the common nondispersive behavior of soft-x-ray transitions between parallel potentials. We evidence a general phenomenon of RXS in the hard-x-ray region: a complete quenching of vibrational broadening. This opens up a unique opportunity for superhigh resolution x-ray spectroscopy beyond vibrational and lifetime limitations.


Energy Efficiency And Capacity For Tcp Traffic In Multi-Hop Wireless Networks, Sorav Bansal, Rajeev Shorey, Rajeev Gupta, Archan Misra Feb 2006

Energy Efficiency And Capacity For Tcp Traffic In Multi-Hop Wireless Networks, Sorav Bansal, Rajeev Shorey, Rajeev Gupta, Archan Misra

Research Collection School Of Computing and Information Systems

We study the performance metrics associated with TCP-regulated traffic in multi-hop, wireless networks that use a common physical channel (e.g., IEEE 802.11). In contrast to earlier analyses, we focus simultaneously on two key operating metrics—the energy efficiency and the transport-layer (TCP) throughput. Using analysis and simulations, we show how these metrics are strongly influenced by the radio transmission range of individual nodes. Due to tradeoffs between the individual packet transmission energy and the likelihood of retransmissions, the total energy consumption is a convex function of the number of hops (and hence, of the transmission range). On the other hand, the …


1,3-Indane-Based Chromogenic Calixpyrroles With Push-Pull Chromophores: Synthesis And Anion Sensing, Ryuhei Nishiyabu, Pavel Anzenbacher Jr. Feb 2006

1,3-Indane-Based Chromogenic Calixpyrroles With Push-Pull Chromophores: Synthesis And Anion Sensing, Ryuhei Nishiyabu, Pavel Anzenbacher Jr.

Chemistry Faculty Publications

Knoevenagel condensation of 2-formyl-octamethylcalix[4]pyrrole with selected 1,3-indanedione derivatives yields calix[4]pyrrole anion sensors with push-pull chromophores displaying strong intramolecular charge transfer. The push-pull feature results in augmented signal output as well as in dramatic changes in anion selectivity exemplified by a 50-fold increase in acetate vs chloride selectivity compared to the parent calix[4]pyrrole.


A Stable Isotopic Investigation Of A Polar Desert Hydrologic System, Mcmurdo Dry Valleys, Antarctica, Michael N. Gooseff, W. Berry Lyons, Diane M. Mcknight, Bruce H. Vaughn, Andrew G. Fountain, Carolyn Dowling Feb 2006

A Stable Isotopic Investigation Of A Polar Desert Hydrologic System, Mcmurdo Dry Valleys, Antarctica, Michael N. Gooseff, W. Berry Lyons, Diane M. Mcknight, Bruce H. Vaughn, Andrew G. Fountain, Carolyn Dowling

Geology Faculty Publications and Presentations

The hydrologic system of the coastal McMurdo Dry Valleys, Antarctica, is defined by snow accumulation, glacier melt, stream flow, and retention in closed-basin, ice-covered lakes. During the austral summers from 1993-1996 and 1999-2000 to 2002-2003, fresh snow, snow pits, glacier ice, stream water, and lake waters were sampled for the stable isotopes deuterium (D) and 18O in order to resolve sources of meltwater and the interactions among the various hydrologic reservoirs in the dry valleys. This data set provides a survey of the distribution of natural water isotope abundances within the well-defined dry valley hydrologic system in Taylor Valley, which …


Text Mining With Exploitation Of User's Background Knowledge : Discovering Novel Association Rules From Text, Xin Chen Jan 2006

Text Mining With Exploitation Of User's Background Knowledge : Discovering Novel Association Rules From Text, Xin Chen

Dissertations

The goal of text mining is to find interesting and non-trivial patterns or knowledge from unstructured documents. Both objective and subjective measures have been proposed in the literature to evaluate the interestingness of discovered patterns. However, objective measures alone are insufficient because such measures do not consider knowledge and interests of the users. Subjective measures require explicit input of user expectations which is difficult or even impossible to obtain in text mining environments.

This study proposes a user-oriented text-mining framework and applies it to the problem of discovering novel association rules from documents. The developed system, uMining, consists of two …


Facial Feature Representation And Recognition, Chao-Fa Chuang Jan 2006

Facial Feature Representation And Recognition, Chao-Fa Chuang

Dissertations

Facial expression provides an important behavioral measure for studies of emotion, cognitive processes, and social interaction. Facial expression representation and recognition have become a promising research area during recent years. Its applications include human-computer interfaces, human emotion analysis, and medical care and cure.

In this dissertation, the fundamental techniques will be first reviewed, and the developments of the novel algorithms and theorems will be presented later. The objective of the proposed algorithm is to provide a reliable, fast, and integrated procedure to recognize either seven prototypical, emotion-specified expressions (e.g., happy, neutral, angry, disgust, fear, sad, and surprise in JAFFE database) …


Color Image Quality Measures And Retrieval, Yan-Yu Fu Jan 2006

Color Image Quality Measures And Retrieval, Yan-Yu Fu

Dissertations

The focus of this dissertation is mainly on color image, especially on the images with lossy compression. Issues related to color quantization, color correction, color image retrieval and color image quality evaluation are addressed. A no-reference color image quality index is proposed. A novel color correction method applied to low bit-rate JPEG image is developed. A novel method for content-based image retrieval based upon combined feature vectors of shape, texture, and color similarities has been suggested. In addition, an image specific color reduction method has been introduced, which allows a 24-bit JPEG image to be shown in the 8-bit color …


Ligand-Based Design Of Dopamine Reuptake Inhibitors : Fuzzy Relational Clustering And 2-D And 3-D Qsar Modleing, Milind Misra Jan 2006

Ligand-Based Design Of Dopamine Reuptake Inhibitors : Fuzzy Relational Clustering And 2-D And 3-D Qsar Modleing, Milind Misra

Dissertations

As the three-dimensional structure of the dopamine transporter (DAT) remains undiscovered, any attempt to model the binding of drug-like ligands to this protein must necessarily include strategies that use ligand information. For flexible ligands that bind to the DAT, the identification of the binding conformation becomes an important but challenging task. In the first part of this work, the selection of a few representative structures as putative binding conformations from a large collection of conformations of a flexible GBR 12909 analogue was demonstrated by cluster analysis. Novel structurebased features that can be easily generalized to other molecules were developed and …


Dynamic Measuring Tools For Online Discourse, Jeffrey S. Saltz Jan 2006

Dynamic Measuring Tools For Online Discourse, Jeffrey S. Saltz

Dissertations

When evaluating participation within an Asynchronous Learning Network (ALN), current best practices include counting messages and reviewing participant surveys. To understand the impact of more advanced dynamic measurement tools for use within an ALN, a web-based tool, known as iPET (the integrated Participation Evaluation Tool), was created. iPET, which leverages Social Network Analysis and Information Visualization techniques, was then evaluated via an empirical study. This research demonstrates that using a tool such as iPET increases participation within an ALN without increasing facilitator workload. Due to the fact that active online discussion is a key factor in the success of an …


Study Of Organic Reactions In Pyridinium-Based Ionic Liquids, Ying Xiao Jan 2006

Study Of Organic Reactions In Pyridinium-Based Ionic Liquids, Ying Xiao

Dissertations

Recently, ionic liquids have attracted a lot of attention as novel materials for organic transformations. This is due to their unique properties, which make them suitable substitutes for organic solvents. Most of the available literature is focused on the application of imidazolium-based ionic liquids for organic reactions, while very limited information is available on the application of pyridinium-based ionic liquids.

In this study, two different ionic liquids, 1 -ethyl-pyridinium tetrafluoroborate ([EtPy]+[BF4]-) and 1 -ethyl-pyridinium trifluoroacetate ([EtPy]+[CF3COO]-) have been investigated. Compared to previous reports, the synthetic technique for preparation …


Quantifying Software Architecture Attributes, Bo Yu Jan 2006

Quantifying Software Architecture Attributes, Bo Yu

Dissertations

Software architecture holds the promise of advancing the state of the art in software engineering. The architecture is emerging as the focal point of many modem reuse/evolutionary paradigms, such as Product Line Engineering, Component Based Software Engineering, and COTS-based software development.

The author focuses his research work on characterizing some properties of a software architecture. He tries to use software metrics to represent the error propagation probabilities, change propagation probabilities, and requirements change propagation probabilities of a software architecture. Error propagation probability reflects the probability that an error that arises in one component of the architecture will propagate to other …


Development Of Environmentally Benign Microencapsulation With Polymer Microspheres And Liposomes, Baohua Yue Jan 2006

Development Of Environmentally Benign Microencapsulation With Polymer Microspheres And Liposomes, Baohua Yue

Dissertations

Microencapsulation means applying a shell-like coating to encapsulate the contents of interest in a particle form with a size range of few micrometers or below. In this work, aqueous liposome systems and polymer based encapsulation of fine particles in supercritical CO2 were studied. Compared to many other microencapsulation methods, these two methodologies feature reduction/prevention of using organic solvents, making them particularly attractive as green technology.

For polymer microencapsulation, a novel in situ polymerization based process to encapsulate various types of fine particles, include drugs, fire retardant, inorganic nanoparticles, and carbon nanotubes, was developed. In the process, host particles, monomers …


Bioinformatics Framework For Genotyping Microarray Data Analysis, Kai Zhang Jan 2006

Bioinformatics Framework For Genotyping Microarray Data Analysis, Kai Zhang

Dissertations

Functional genomics is a flourishing science enabled by recent technological breakthroughs in high-throughput instrumentation and microarray data analysis. Genotyping microarrays establish the genotypes of DNA sequences containing single nucleotide polymorphisms (SNPs), and can help biologists probe the functions of different genes and/or construct complex gene interaction networks. The enormous amount of data from these experiments makes it infeasible to perform manual processing to obtain accurate and reliable results in daily routines. Advanced algorithms as well as an integrated software toolkit are needed to help perform reliable and fast data analysis.

The author developed a MatlabTM based software package, called …


Environmental Justice Education And Atmospheric Particulate Analysis In Urban Environmental Health Policy Development : Indoor Airborne Particulate Concentrations In Preschools Of Asthmatic Children In Newark, Rita L. Thornton Jan 2006

Environmental Justice Education And Atmospheric Particulate Analysis In Urban Environmental Health Policy Development : Indoor Airborne Particulate Concentrations In Preschools Of Asthmatic Children In Newark, Rita L. Thornton

Dissertations

Analysis suggests that several residential areas in Newark, New Jersey (USA) have Black/African-American and Hispanic populations, which may be "at high risk" with respect to the adverse health effects of particulate air pollution. This study analyzes the community locations and evaluates literature and other available air pollution data for the target communities in the city of Newark. The study focuses on asthma or reactive airway diseases as a target health risk. It also performs data collection on particulate pollutants and levels of trace metals in particulate matter in target communities and schools of preschool children in two of the five …


Using Content And Process Scaffolds For Collaborative Discourse In Asynchronous Learning Networks, Irene Wong-Bushby Jan 2006

Using Content And Process Scaffolds For Collaborative Discourse In Asynchronous Learning Networks, Irene Wong-Bushby

Dissertations

Discourse, a form of collaborative learning, is one of the most widely used methods of teaching and learning in the online environment. Particularly, in large courses, discourse needs to be 'structured' to be effective. Historically, technology-mediated learning (TML) research has been inconclusive with often conflicting results. To address this issue, TML research needs greater breadth and depth in pedagogical grounding. The purpose of this research is to build and test an original, technology-mediated, discourse-centered model called the Asynchronous Learning Network Cognitive Discourse Model (ALNCDM) grounded in pedagogy. Cognitive discourse is defined as discourse on conceptual subject matter. The model is …


Image Segmentation And Pattern Classification Using Support Vector Machines, Shouxian Cheng Jan 2006

Image Segmentation And Pattern Classification Using Support Vector Machines, Shouxian Cheng

Dissertations

Image segmentation and pattern classification have long been important topics in computer science research. Image segmentation is one of the basic and challenging lower-level image processing tasks. Feature extraction, feature reduction, and classifier design based on selected features are the three essential issues for the pattern classification problem.

In this dissertation, an automatic Seeded Region Growing (SRG) algorithm for color image segmentation is developed. In the SRG algorithm, the initial seeds are automatically determined. An adaptive morphological edge-linking algorithm to fill in the gaps between edge segments is designed. Broken edges are extended along their slope directions by using the …


Automatic Solar Feature Detection Using Image Processing And Pattern Recognition Techniques, Ming Qu Jan 2006

Automatic Solar Feature Detection Using Image Processing And Pattern Recognition Techniques, Ming Qu

Dissertations

The objective of the research in this dissertation is to develop a software system to automatically detect and characterize solar flares, filaments and Corona Mass Ejections (CMEs), the core of so-called solar activity. These tools will assist us to predict space weather caused by violent solar activity. Image processing and pattern recognition techniques are applied to this system.

For automatic flare detection, the advanced pattern recognition techniques such as Multi-Layer Perceptron (MLP), Radial Basis Function (RBF), and Support Vector Machine (SVM) are used. By tracking the entire process of flares, the motion properties of two-ribbon flares are derived automatically. In …


Model Driven Architecture - A Tool For Enterprise Architecture : A Look At Emergency Response Systems, Ritu Lamba Jan 2006

Model Driven Architecture - A Tool For Enterprise Architecture : A Look At Emergency Response Systems, Ritu Lamba

Theses

Today's fast changing markets and technology drive software industry to deliver high quality enterprise software solutions. The enterprise system architecture should be designed to keep business functions separate from technological implementation to accommodate the fast changing business environment.

In this thesis we have studied the current best practices in defining enterprise architectures and Zachman's framework in particular. We have further examined the Model Driven Architecture (MDA) approach and its application to enterprise architecture definition. MDA separates the business logic from the underlying platform technology and defines a representation model based on precise semantics. Zachman's framework defines a set of views …


Classifying Malicious Windows Executables Using Anomaly Based Detection, Ronak Sutaria Jan 2006

Classifying Malicious Windows Executables Using Anomaly Based Detection, Ronak Sutaria

Theses

A malicious executable is broadly defined as any program or piece of code designed to cause damage to a system or the information it contains, or to prevent the system from being used in a normal manner. A generic term used to describe any kind of malicious software is Maiware, which includes Viruses, Worms, Trojans, Backdoors, Root-kits, Spyware and Exploits. Anomaly detection is technique which builds a statistical profile of the normal and malicious data and classifies unseen data based on these two profiles.

A detection system is presented here which is anomaly based and focuses on the Windows® platform. …


A New Approach To Feature Extraction For Rna Structure Comparision, Girish Prakash Walawalkar Jan 2006

A New Approach To Feature Extraction For Rna Structure Comparision, Girish Prakash Walawalkar

Theses

In recent years, RNA structural comparison becomes a crucial problem in bioinformatics research. Generally, it is a popular approach for representing the RNA secondary structures with arc-annotation sets. Several methods can be used to compare two RNA structures, such as tree edit distance, longest arc-preserving common subsequence (LAPCS) and stem based alignment. However, these methods may be helpful only for small RNA structures because of their high time complexity. In this thesis, we propose a simplified method to compare two RNA structures in O(mn) time, where m and n are the lengths of the two RNA sequences, respectively. The method …


Classifying Rna Secondary Structures Using Support Vector Machines, Prathy Usha Sunkara Jan 2006

Classifying Rna Secondary Structures Using Support Vector Machines, Prathy Usha Sunkara

Theses

In contrast to DNA, RNA prevails as a single strand. As a consequence of small self-complementary regions, RNA commonly exhibits an intricate secondary structure, consisting of relatively short, double helical segments alternated with single stranded regions. The amount of sequence data available is rising rapidly day by day. One of the problems encountered on a specific molecule is finding the relevant data between the massive number of other sequences to be done by reading lists with a short description of all new entries in large databases already existing. One of the main objectives of this work is to take the …


Nonadditivity In Van Der Waals Interactions Within Multilayers, Roger H. French Jan 2006

Nonadditivity In Van Der Waals Interactions Within Multilayers, Roger H. French

Faculty Scholarship

Working at the macroscopic continuum level, we investigate effective van der Waals interactions between two layers within a multilayer assembly. By comparing the pair interactions between two layers with effective pair interactions within an assembly we assess the significant consequences of nonadditivity of van der Waals interactions. This allows us to evaluate the best numerical estimate to date for the Hamaker coefficient of van der Waals interactions in lipid-water multilamellar systems.


Bat House Construction And Installation, Stephen Vantassel, Scott E. Hygnstrom, Ron J. Johnson, Dennis Ferraro Jan 2006

Bat House Construction And Installation, Stephen Vantassel, Scott E. Hygnstrom, Ron J. Johnson, Dennis Ferraro

Other Publications in Wildlife Management

Bat house construction and installation can be an environmentally friendly and rewarding activity. Putting up a bat house, however, does not guarantee that bats will use it. We don't know exactly why bats dwell in one house and not another, but by following a few recommendations you can increase the likelihood that bats will live in your bat house.

Some bats live in colonies that include tens of thousands of individuals. In Nebraska, the big brown bat (Eptesicus fuscus) and little brown bat (Myotis lucifugus) live in colonies of 10 to 200 and are the most …


Perennial Warm Season Grasses In Grazing Programs, Mark Kennedy Jan 2006

Perennial Warm Season Grasses In Grazing Programs, Mark Kennedy

Kentucky Grazing Conference

Many warm season perennial grasses were once an important part of the plant community in much of the Midwest. Conversion to cropping systems, overgrazing, lack of regular fire and increased competition from cool-season grasses and legumes have caused many of these grasses to disappear from much of the region. However, warm season grasses can compliment cool-season pastures if managed properly. Midwest stockmen are rediscovering the usefulness of warm season grasses in their overall forage program. Adding these grasses to forage systems has resulted in increased gains and improved livestock performance during the summer months when cool-season grasses are at their …