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2006

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Articles 4681 - 4710 of 4906

Full-Text Articles in Physical Sciences and Mathematics

A Class Of Nonlinear Stochastic Volatility Models, Jun Yu, Zhenlin Yang Jan 2006

A Class Of Nonlinear Stochastic Volatility Models, Jun Yu, Zhenlin Yang

Research Collection School Of Economics

This paper proposes a class of nonlinear stochastic volatility models based on the Box-Cox transformation which offers an alternative to the one introduced in Andersen (1994). The proposed class encompasses many parametric stochastic volatility models that have appeared in the literature, including the well known lognormal stochastic volatility model, and has an advantage in the ease with which different specifications on stochastic volatility can be tested. In addition, the functional form of transformation which induces marginal normality of volatility is obtained as a byproduct of this general way of modeling stochastic volatility. The efficient method of moments approach is used …

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Relation Of Riparian Buffer Strips To In-Stream Habitat, Macroinvertebrates And Fish In A Small Iowa Stream, Jeremy P. Duehr, Michael J. Siepker, Clay L. Pierce, Thomas M. Isenhart Jan 2006

Relation Of Riparian Buffer Strips To In-Stream Habitat, Macroinvertebrates And Fish In A Small Iowa Stream, Jeremy P. Duehr, Michael J. Siepker, Clay L. Pierce, Thomas M. Isenhart

Journal of the Iowa Academy of Science: JIAS

Macroinvertebrate and fish habitat is often degraded as a result of agriculture. Riparian buffer strips are commonly used to counteract the negative effects of agriculture in headwater streams. We assessed the relation of multi-aged riparian buffer strips to in-stream habitat, macroinvertebrate and fish assemblages in an Iowa stream. In-stream habitat, macroinvertebrates, and fish were sampled from two buffered sites and two unbuffered sites, with the greatest substrate, water depth, and velocity heterogeneity occurring in buffered sites. The highest macroinvertebrate richness (11) as well as fish species richness (14), diversity (1.99) and IBI score (3 7) were found in the site …

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Research Plan And Preliminary Results - A Field Research Site For Emerging Contaminants In Iowa, Douglas J. Schnoebelen, Dana W. Kolpin, Larry B. Barber, Edward T. Furlong, Michael M. Meyer, Mary Skopec Jan 2006

Research Plan And Preliminary Results - A Field Research Site For Emerging Contaminants In Iowa, Douglas J. Schnoebelen, Dana W. Kolpin, Larry B. Barber, Edward T. Furlong, Michael M. Meyer, Mary Skopec

Journal of the Iowa Academy of Science: JIAS

Research has recently documented the prevalence of a wide variety of pharmaceuticals and other emerging contaminants (ECs) in streams across the United States. Wastewater treatment plants (WWTPs) have been found to be an important source and collection point of ECs to streams as many ECs are incompletely removed during treatment. To investigate the complex instream processes (e.g., dilution, sorption, degradation, dispersion, etc.) chat can affect ECs following their input from a WWTP and determining if such input is having an effect on the aquatic ecosystem requires the integration of multi-disciplinary efforts at a carefully selected field site. Preliminary work has …

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Cover - Table Of Contents Jan 2006

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

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The Honey Creek Member: A New Holocene Alluvial Stratigraphic Unit In The Midwest, Jeremy S. Dillon, Rolfe D. Mandel Jan 2006

The Honey Creek Member: A New Holocene Alluvial Stratigraphic Unit In The Midwest, Jeremy S. Dillon, Rolfe D. Mandel

Journal of the Iowa Academy of Science: JIAS

This paper describes the type locality and type section for the Honey Creek Member, a stratigraphic unit first recognized in the Honey Creek drainage in southeastern Nebraska. The alluvial chronology for Honey Creek basin is similar to the regional chronology of streams in the Midwest, and all of the formal members of the DeForest Formation occur in the basin. However, the lithology of one unit, the Honey Creek Member, does not correlate with any of the formally recognized members of the DeForest Formation. The Honey Creek Member is composed of grayish brown silt loam overbank facies coarsening downward to a …

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Silicification Of Corals, Stromatoporids, And Brachiopods At The Weathered Surface Within The Devonian-Age Little Cedar Formation (Solon And Rapid Members) In Eastern Iowa, Adam L. Majeski, Paul L. Garvin Jan 2006

Silicification Of Corals, Stromatoporids, And Brachiopods At The Weathered Surface Within The Devonian-Age Little Cedar Formation (Solon And Rapid Members) In Eastern Iowa, Adam L. Majeski, Paul L. Garvin

Journal of the Iowa Academy of Science: JIAS

Diagenesis of fossils contained in middle-Devonian limestones was studied at the Troy Mills and Robins quarries in Linn County, Iowa and at the Four County and Ernst quarries in Johnson County, Iowa. Fossils located at weathered bedrock surfaces were preferentially silicified, and the silicification affected corals, stromatoporids and, to a limited extent, brachiopods, but not other fossils or the host rock. The siliceous horizon extends no more than a few centimeters below the weathered surfaces, suggesting that silicification was constrained by them. Silica for silicification might have come from a variety of sources, including sponge spicules or radiolarian tests, insoluble …

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Relation Of Riparian Buffer Strips To In-Stream Habitat, Macroinvertebrates And Fish In A Small Iowa Stream, Jeremy P. Duehr, Michael J. Siepker, Clay L. Pierce, Thomas M. Isenhart Jan 2006

Relation Of Riparian Buffer Strips To In-Stream Habitat, Macroinvertebrates And Fish In A Small Iowa Stream, Jeremy P. Duehr, Michael J. Siepker, Clay L. Pierce, Thomas M. Isenhart

Journal of the Iowa Academy of Science: JIAS

Macroinvertebrate and fish habitat is often degraded as a result of agriculture. Riparian buffer strips are commonly used to counteract the negative effects of agriculture in headwater streams. We assessed the relation of multi-aged riparian buffer strips to in-stream habitat, macroinvertebrate and fish assemblages in an Iowa stream. In-stream habitat, macroinvertebrates, and fish were sampled from two buffered sites and two unbuffered sites, with the greatest substrate, water depth, and velocity heterogeneity occurring in buffered sites. The highest macroinvertebrate richness (11) as well as fish species richness (14), diversity (1.99) and IBI score (37) were found in the site buffered …

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Counting Coffee Combinations: An Example Of The Fundamental Principle Of Counting, David R. Duncan, Bonnie H. Litwiller Jan 2006

Counting Coffee Combinations: An Example Of The Fundamental Principle Of Counting, David R. Duncan, Bonnie H. Litwiller

Faculty Work

Teachers in courses which involve probability and statistics are always looking for situations in which the Fundamental Principle of Counting (FPC) can be exemplified. We shall present an example involving a coffee vending machine at a highway rest stop.

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The Geoprofile Metadata, Exposure Of Instruments, And Measurement Bias In Climatic Record Revisited, Rezaul Mahmood Jan 2006

The Geoprofile Metadata, Exposure Of Instruments, And Measurement Bias In Climatic Record Revisited, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

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Fedcor: An Institutional Cordra Registry, Giridhar Manepalli, Henry Jerez, Michael L. Nelson Jan 2006

Fedcor: An Institutional Cordra Registry, Giridhar Manepalli, Henry Jerez, Michael L. Nelson

Computer Science Faculty Publications

FeDCOR (Federation of DSpace using CORDRA) is a registry-based federation system for DSpace instances. It is based on the CORDRA model. The first article in this issue of D-Lib Magazine describes the Advanced Distributed Learning-Registry (ADL-R) [1], which is the first operational CORDRA registry, and also includes an introduction to CORDRA. That introduction, or other prior knowledge of the CORDRA effort, is recommended for the best understanding of this article, which builds on that base to describe in detail the FeDCOR approach.

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The Challenges Of Itil Implementations, Jason Gray Jan 2006

The Challenges Of Itil Implementations, Jason Gray

Theses : Honours

Originating from the UK, the IT Infrastructure Library (ITIL) is an IT Service Management framework whose adoption is rapidly spreading throughout Canada, Netherlands, South Africa, India, USA, and Australia. Promoted as a collection of "Best Practices" in IT service management, ITIL is gaining a reputation as a "silver bullet" to IT Service Management woes and is now .gaining popularity amongst IT vendors and leaders of best practices worldwide. Increased IT productivity, IT accountability, increased compliance and reduced IT costs, are just some of the promised list of benefits. More and more organisations are plam1ing to embark on ITIL implementations as …

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Radio Frequency Enabled Soil Redox Potential Sensor Networks, Chris Holme Jan 2006

Radio Frequency Enabled Soil Redox Potential Sensor Networks, Chris Holme

Theses : Honours

There is a need for' cost effective tools and data collection methods for field measurements; to increase both productivity and volumes of collected data in the quest for enhanced understanding and management of environmental systems. To such end, various technologies that may be combined into a cost effective soil redox sensor network were explored. Suitability of each technology, as a component of said network was evaluated. A prototype soil redox sensor network was constructed and basic laboratory and field testing was completed. Results indicate that the prototype sensor network functions correctly within bounds. Both laboratory and field testing show that …

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The Determination Of Probes For The Indirect Detection Of Anions In Capillary Zone Electrophoresis Using Light Emitting Diode Detection, Peter Ashley Balding Jan 2006

The Determination Of Probes For The Indirect Detection Of Anions In Capillary Zone Electrophoresis Using Light Emitting Diode Detection, Peter Ashley Balding

Theses : Honours

This study investigated the potential of a number of compounds to act as probes for the indirect detection of inorganic and organic anions separated by capillary zone electrophoresis and using light emitting diodes (LED) as the light source. Desirable characteristics of the probe anion included: high molar absorptivity, moderate to high electrophoretic mobility, and having a wavelength of maximum absorbance near the maximum emission wavelength of a LED. A preliminary study led to the evaluation of eleven possible compounds. Two of these, p-nitrophenol and 4-hydroxy-3,5-dinitrobenzoic acid were selected for further study as they fulfilled the criteria previously mentioned. The optimised …

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Evaluating The Impact Of Peer Review And Participation Awareness In An Online Collaborative Document Authoring Environment, Greg Baatard Jan 2006

Evaluating The Impact Of Peer Review And Participation Awareness In An Online Collaborative Document Authoring Environment, Greg Baatard

Theses : Honours

Online Learning Environments (OLEs) have been widely adopted by higher education facilities, offering distance education with the potential to support the social and collaborative aspects deemed crucial to modern constructivist pedagogy. Groupware, a form of software which aims to facilitate group work, has been the subject of much research, from both educational and enterprise perspectives. This research introduced Reportal, an online groupware system designed to facilitate the collaborative authoring of a document. Reportal's peer review and participation awareness features were the focus of this research, and their impact was measured against the elements of online collaboration, a typology established by …

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An Attitude And Perception Study Of Wireless Network Usage In Home Environments, Patryk Szewczyk Jan 2006

An Attitude And Perception Study Of Wireless Network Usage In Home Environments, Patryk Szewczyk

Theses : Honours

Research on the use of 802.11 wireless networking and wireless security has in the past focused predominantly on corporations who generally have access to resources specifically allocated to computer and network security. Research has also focused on identifying the flaws in wireless network security, and developing stronger and safer methods which may be incorporated. To date there has been a lack of research into determining what the individual at home perceives towards wireless security. As broadband Internet connections are now predominantly chosen, the amount of available bandwidth open to exploitation is significantly higher than the now becoming obsolete dialup connection. …

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Use Of A Weighted Matching Algorithm To Sequence Clusters In Spatial Join Processing, Husen Husen Jan 2006

Use Of A Weighted Matching Algorithm To Sequence Clusters In Spatial Join Processing, Husen Husen

Theses : Honours

One of the most expensive operations in a spatial database is spatial join processing. This study focuses on how to improve the performance of such processing. The main objective is to reduce the Input/Output (I/O) cost of the spatial join process by using a technique called cluster-scheduling. Generally, the spatial join is processed in two steps, namely filtering and refinement. The cluster-scheduling technique is performed after the filtering step and before the refinement step and is part of the housekeeping phase. The key point of this technique is to realise order wherein two consecutive clusters in the sequence have maximal …

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Insurance: A Consumer's Perspective, Elizabeth Ann Nanke Jan 2006

Insurance: A Consumer's Perspective, Elizabeth Ann Nanke

Honors Program Theses

Life insurance is a pivotal part of the world in which we live, and yet most consumers think about it very little. Life insurance started with the Ancient Greeks and continued to develop in Europe, eventually reaching the United States. Throughout history, insurance companies have undergone a number of modifications to match changing consumer needs. ln our modem society, insurance can be best defined as an intermediary that reduces the financial drain caused by the death of an individual by apportioning this loss among a very large group. Today, insurance companies sell a number of diversified products, but most insurance …

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Asbestos Litigation And Indemnification, Paul Grammens Jan 2006

Asbestos Litigation And Indemnification, Paul Grammens

Honors Program Theses

Asbestos started out as an amazing product. It was not only easy to manufacture and easy to work with but also fire resistant and a great insulator, asbestos became one of the most common manufacturing products in the United States, especially after World War I. What the public did not know about asbestos at the time is that long-term exposure could lead to sickness. Because of this unforeseen liability, industrial companies and insurance companies were not able to properly prepare for the losses due to asbestos.

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Testcase Tool, John Louis Van Hemert Jan 2006

Testcase Tool, John Louis Van Hemert

Honors Program Theses

The title of my project is "TestCASE Tool." TestCASE Tool is the name, or label, I assigned to the software application that I created for this project. The application is a Tool for storing and reporting data in software testing projects. A Test Case consists of a planned action within a system, the expected result of that action and an assessment of whether the expected result occurred. The acronym, CASE, stands for Computer Aided Software Engineering, which is the software tool genre to which my application belongs.

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Radon In Caves: Clinical Aspects, Stephen A. Craven, Berend J. Smit Jan 2006

Radon In Caves: Clinical Aspects, Stephen A. Craven, Berend J. Smit

International Journal of Speleology

Historical, experimental and clinical evidence is presented to suggest that radon constitutes a relatively small carcinogenic risk for casual visitors to caves. The risk is dependent on radon levels and the smoking of tobacco. Show cave guides, chronically exposed to radon, may be at increased risk for lung cancer due to the effects of radon, especially if they are smokers of tobacco.

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Observed Web Robot Behavior On Decaying Web Subsites, Joan A. Smith, Frank Mccown, Michael L. Nelson Jan 2006

Observed Web Robot Behavior On Decaying Web Subsites, Joan A. Smith, Frank Mccown, Michael L. Nelson

Computer Science Faculty Publications

We describe the observed crawling patterns of various search engines (including Google, Yahoo and MSN) as they traverse a series of web subsites whose contents decay at predetermined rates. We plot the progress of the crawlers through the subsites, and their behaviors regarding the various file types included in the web subsites. We chose decaying subsites because we were originally interested in tracking the implication of using search engine caches for digital preservation. However, some of the crawling behaviors themselves proved to be interesting and have implications on using a search engine as an interface to a digital library.

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Splai: Computational Finite Element Model For Sensor Networks, Ruzana Ishak, Shadaruddin Salleh, Stephan Olariu, Mohd.Ismail Abdul Aziz Jan 2006

Splai: Computational Finite Element Model For Sensor Networks, Ruzana Ishak, Shadaruddin Salleh, Stephan Olariu, Mohd.Ismail Abdul Aziz

Computer Science Faculty Publications

Wireless sensor network refers to a group of sensors, linked by a wireless medium to perform distributed sensing task. The primary interest is their capability in monitoring the physical environment through the deployment of numerous tiny, intelligent, wireless networked sensor nodes. Our interest consists of a sensor network, which includes a few specialized nodes called processing elements that can perform some limited computational capabilities. In this paper, we propose a model called SPLAI that allows the network to compute a finite element problem where the processing elements are modeled as the nodes in the linear triangular approximation problem. Our model …

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Synchronization And Multiple Group Server Support For Kepler, K. Maly, M. Zubair, H. Siripuram, S. Zunjarwad, Yannis Manolopoulos (Ed.), Joaquim Filipe (Ed.), Panos Constantopoulos (Ed.), José Cordeiro (Ed.) Jan 2006

Synchronization And Multiple Group Server Support For Kepler, K. Maly, M. Zubair, H. Siripuram, S. Zunjarwad, Yannis Manolopoulos (Ed.), Joaquim Filipe (Ed.), Panos Constantopoulos (Ed.), José Cordeiro (Ed.)

Computer Science Faculty Publications

In the last decade literally thousands of digital libraries have emerged but one of the biggest obstacles for dissemination of information to a user community is that many digital libraries use different, proprietary technologies that inhibit interoperability. Kepler framework addresses interoperability and gives publication control to individual publishers. In Kepler, OAI-PMH is used to support "personal data providers" or "archivelets".". In our vision, individual publishers can be integrated with an institutional repository like Dspace by means of a Kepler Group Digital Library (GDL). The GDL aggregates metadata and full text from archivelets and can act as an OAI-compliant data provider …

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Iowa Academy Of Science 118th Annual Meeting [2006]: Advance Program, Iowa Academy Of Science Jan 2006

Iowa Academy Of Science 118th Annual Meeting [2006]: Advance Program, Iowa Academy Of Science

Iowa Academy of Science Documents

Contains information about the schedule and presentations for the 2006 annual meeting of the Iowa Academy of Science.

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Chironomid Hemoglobin Genetic Diversity As An Indicator Of The New Jersey Hackensack Meadowlands Wetland Health, Lene Marie De Coursin Jacobs Jan 2006

Chironomid Hemoglobin Genetic Diversity As An Indicator Of The New Jersey Hackensack Meadowlands Wetland Health, Lene Marie De Coursin Jacobs

Seton Hall University Dissertations and Theses (ETDs)

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Gp120 Up-Regulation Of The Mu Opioid Receptor In Tpa Differentiated Hl-60 Cells, Anitha Pallur Jan 2006

Gp120 Up-Regulation Of The Mu Opioid Receptor In Tpa Differentiated Hl-60 Cells, Anitha Pallur

Seton Hall University Dissertations and Theses (ETDs)

.

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Puncturing Ability Of Idealized Canine Teeth: Edged And Non-Edged Shanks, Patricia W. Freeman, Cliff A. Lemen Jan 2006

Puncturing Ability Of Idealized Canine Teeth: Edged And Non-Edged Shanks, Patricia W. Freeman, Cliff A. Lemen

School of Natural Resources: Faculty Publications

Idealized edged and non-edged indenters, mimicking canine teeth, were used to puncture thin materials and thick materials. Less force was needed for the edged (triangular in cross section) indenter to penetrate thin Mylar, paper, leather, beetle elytra and turkey skin than the non-edged (circular in cross-section) indenter. Oak, grass and magnolia leaves responded equally to both indenters. In thick materials, the edged indenter punctured beetles, shrimp, bananas, and chicken flesh more easily than the non-edged indenter. Apple, tomato and avocado were punctured equally well. The edged indenter directs cracks at the corners so that the material can fold away in …

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Geology Of Cat Island, Bahamas: A Field Trip Guide, John E. Mylroie, H. Allen Curran, Deborah Freile, James L. Carew, Neil E. Sealey, Vincent J. Voegeli Jan 2006

Geology Of Cat Island, Bahamas: A Field Trip Guide, John E. Mylroie, H. Allen Curran, Deborah Freile, James L. Carew, Neil E. Sealey, Vincent J. Voegeli

Geosciences: Faculty Publications

See other Smith authored Field Trip Guides of Gerace Research Centre.

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Eigenvalue Comparisons For Boundary Value Problems Of The Discrete Beam Equation, Jun Ji, Bo Yang Jan 2006

Eigenvalue Comparisons For Boundary Value Problems Of The Discrete Beam Equation, Jun Ji, Bo Yang

Faculty Articles

We study the behavior of all eigenvalues for boundary value problems of fourth-order difference equations Delta(4)yi = lambda a(i+2)y(i+2), - 1= b(j), 1

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Soft-Gluon Corrections In Hard-Scattering Processes Through Nnnlo, Nikolaos Kidonakis Jan 2006

Soft-Gluon Corrections In Hard-Scattering Processes Through Nnnlo, Nikolaos Kidonakis

Faculty Articles

I discuss soft-gluon corrections in hard-scattering processes and their resummation. I present master formulas for the expansion of the resummed cross section through NNNLO and discuss the significance of these corrections in a number of processes.

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