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2009

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Articles 751 - 780 of 7701

Full-Text Articles in Physical Sciences and Mathematics

Why Should I Improve My Grazing Program?, Garry D. Lacefield Oct 2009

Why Should I Improve My Grazing Program?, Garry D. Lacefield

Kentucky Grazing Conference

Grazing represents the cheapest way to feed ruminants on a cost per pound of nutrient basis. Stored feed is usually the single largest item in livestock budgets and cost or amount of stored feed is usually the best prediction of potential profitability in most beef cattle operations.

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Foreword And Kfgc Award Winners [2009], Garry D. Lacefield, Christi L. Forsythe Oct 2009

Foreword And Kfgc Award Winners [2009], Garry D. Lacefield, Christi L. Forsythe

Kentucky Grazing Conference

No abstract provided.

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Farmers’ Willingness To Adopt Agricultural Best Management Practices To Control Nonpoint Source Pollution In The Lower Bhavani River Basin, Tamilnadu, India, Sacchidananda Mukherjee Oct 2009

Farmers’ Willingness To Adopt Agricultural Best Management Practices To Control Nonpoint Source Pollution In The Lower Bhavani River Basin, Tamilnadu, India, Sacchidananda Mukherjee

Sacchidananda Mukherjee

The role of stakeholders and their voluntary participation in agri-environmental management in general and water resources conservation in particular is a new area of research, at least for a developing country like India. This study attempts to understand the factors influencing farmers’ willingness to adopt agricultural Best Management Practices (BMPs) to protect groundwater from nonpoint sources of pollution. Based on long term groundwater nitrate concentration and source(s) of irrigation six villages selected in the Lower Bhavani River Basin, Tamilnadu and detailed questionnaire survey (face-to-face interviews) has been carried out among 395 farm households. The results of binary choice Probit models …

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Differential Cross Sections For The Reactions Γp→Pη And Γp→Pη', M. Williams, Gerard P. Gilfoyle, Et. Al. Oct 2009

Differential Cross Sections For The Reactions Γp→Pη And Γp→Pη', M. Williams, Gerard P. Gilfoyle, Et. Al.

Physics Faculty Publications

High-statistics differential cross sections for the reactions γp → pη and γp → pη' have been measured using the CEBAF large acceptance spectrometer (CLAS) at Jefferson Lab for center-of-mass energies from near threshold up to 2.84 GeV. The η' results are the most precise to date and provide the largest energy and angular coverage. The η measurements extend the energy range of the world’s large-angle results by approximately 300 MeV. These new data, in particular the η' measurements, are likely to help constrain the analyses being performed to search for new baryon resonance states.

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Terrain Constrained Stereo Correspondence, Gabrielle Inglis, Chris Roman Oct 2009

Terrain Constrained Stereo Correspondence, Gabrielle Inglis, Chris Roman

Graduate School of Oceanography Faculty Publications

There is a persistent need in the oceanographic community for accurate three dimensional reconstructions of seafloor structures. To meet this need underwater mapping techniques have expanded to include the use of stereo vision and high frequency multibeam sonar for mapping scenes 10's to 100's of square meters in size. Both techniques have relative advantages and disadvantages that depend on the task at hand and the desired accuracy. In this paper, we develop a method to constrain the often problematic stereo correspondence search to small sections of the image that correspond to estimated ranges along the epipolar lines calculated from coregistered …

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Modeling Soil Depth From Topographic And Land Cover Attributes, Teklu K. Tesfa, David G. Tarboton, David G. Chandler, James P. Mcnamara Oct 2009

Modeling Soil Depth From Topographic And Land Cover Attributes, Teklu K. Tesfa, David G. Tarboton, David G. Chandler, James P. Mcnamara

Geosciences Faculty Publications and Presentations

Soil depth is an important input parameter in hydrological and ecological modeling. Presently, the soil depth data available in national soil databases (STATSGO and SSURGO) from the Natural Resources Conservation Service are provided as averages within generalized land units (map units). Spatial uncertainty within these units limits their applicability for distributed modeling in complex terrain. This work reports statistical models for prediction of soil depth in a semiarid mountainous watershed that are based upon the relationship between soil depth and topographic and land cover attributes. Soil depth was surveyed by driving a rod into the ground until refusal at locations …

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Phev Parcel Delivery Truck Model - Development And Preliminary Results, R. Barnitt Oct 2009

Phev Parcel Delivery Truck Model - Development And Preliminary Results, R. Barnitt

Publications (T)

Describes results of a study to determine the impact of drive cycles on the energy- and cost-effectiveness of plug-in hybrid electric delivery vans.

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Effects Of Gravitational Slip On The Higher-Order Moments Of The Matter Distribution, Scott F. Daniel Oct 2009

Effects Of Gravitational Slip On The Higher-Order Moments Of The Matter Distribution, Scott F. Daniel

Dartmouth Scholarship

Cosmological departures from general relativity offer a possible explanation for the cosmic acceleration. To linear order, these departures (quantified by the model-independent parameter ϖ, referred to as a “gravitational slip”) amplify or suppress the growth of structure in the universe relative to what we would expect to see from a general relativistic universe lately dominated by a cosmological constant. As structures collapse and become more dense, linear perturbation theory is an inadequate descriptor of their behavior, and one must extend calculations to nonlinear order. If the effects of gravitational slip extend to these higher orders, we might expect to see …

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Ion Observations From Geosynchronous Orbit As A Proxy For Ion Cyclotron Wave Growth During Storm Times, L. W. Blum, E. A. Macdonald, S. P. Gary, M. F. Thomsen, Harlan E. Spence Oct 2009

Ion Observations From Geosynchronous Orbit As A Proxy For Ion Cyclotron Wave Growth During Storm Times, L. W. Blum, E. A. Macdonald, S. P. Gary, M. F. Thomsen, Harlan E. Spence

Physics & Astronomy

[1] There is still much to be understood about the processes contributing to relativistic electron enhancements and losses in the radiation belts. Wave particle interactions with both whistler and electromagnetic ion cyclotron (EMIC) waves may precipitate or accelerate these electrons. This study examines the relation between EMIC waves and resulting relativistic electron flux levels after geomagnetic storms. A proxy for enhanced EMIC waves is developed using Los Alamos National Laboratory Magnetospheric Plasma Analyzer plasma data from geosynchronous orbit in conjunction with linear theory. In a statistical study using superposed epoch analysis, it is found that for storms resulting in net …

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A General Asymmetric Aldol Reaction Of Silyl Ketene Acetals Derived From Simple Esters To Aryl Alpha-Ketoesters, Brian Pagenkopf, Julie Le Engers Oct 2009

A General Asymmetric Aldol Reaction Of Silyl Ketene Acetals Derived From Simple Esters To Aryl Alpha-Ketoesters, Brian Pagenkopf, Julie Le Engers

Chemistry Publications

No abstract provided.

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Gauging The Impact Of Journals, Jerome K. Vanclay Oct 2009

Gauging The Impact Of Journals, Jerome K. Vanclay

Professor Jerome K Vanclay

Many stakeholders, including authors, editors, librarians and funding agencies, have an interest in reliable assessments of journal impact, but the provision of this service has long been dominated by a single service, the Journal Impact Factor (JIF; Garfield, 1955) provided by the ISI and Thomson Scientific. Despite several limitations (Hecht et al., 1998; Moed et al., 1999; van Leeuwen et al., 1999; Saha et al., 2003; Dong et al., 2005; Moed, 2005; Dellavalle et al., 2007), the JIF continues to be the dominant indicator of journal performance. Recently, Hirsch’s h-index (Hirsch, 2005; Bornmann and Daniel, 2007) has been suggested as …

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Indicator Groups And Faunal Richness, Jerome K. Vanclay Oct 2009

Indicator Groups And Faunal Richness, Jerome K. Vanclay

Professor Jerome K Vanclay

Species richness is a popular indicator of ecosystem vitality, but is difficult to assess. Many natural resource managers seek an efficient bioindicator, but the link between candidate indicators and the richness of other taxononic groups remains elusive. A series of faunal surveys in the Mbalmayo Forest Reserve in Cameroon suggest that it may be possible to devise faunal bioindicators. The species richness of birds, of butterflies and of termites is significantly correlated with total faunal richness across eight species groups, suggesting that these groups may have potential as bioindicators, alone or in combination. Although expensive, further research is warranted because …

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Site Index Equation For Smallholder Plantations Of Gmelina Arborea In Leyte Province, The Philippines, Jerome K. Vanclay, Jack Baynes, Edwin Cedamon Oct 2009

Site Index Equation For Smallholder Plantations Of Gmelina Arborea In Leyte Province, The Philippines, Jerome K. Vanclay, Jack Baynes, Edwin Cedamon

Professor Jerome K Vanclay

The equation SiteIndex = Height × Log(IndexYear+0.5) / Log(Age+0.5) is suggested as a robust way to classify site index of small private Gmelina arborea plantations in Leyte province in the Philippines. Estimates of site index from this equation correlate well with other indicators of site productivity, including the observed mean annual volume increment and soil depth. An alternative equation based on slope and soil depth offers an indication of potential site productivity on unforested sites where no crop trees are present.

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Managing Water Use From Forest Plantations, Jerome K. Vanclay Oct 2009

Managing Water Use From Forest Plantations, Jerome K. Vanclay

Professor Jerome K Vanclay

Tree plantations have developed a reputation for excessive water use, with age commonly used as an explanatory variable to predict water loss – but many factors have the potential to affect plantation water use, and few of these alternatives have been considered. Changes in forest cover may be correlated with other environmental changes that may affect precipitation, transpiration, and runoff, indicating that more thorough investigation is required in both field and simulation studies. Several factors influencing water use by plantations are amenable to management control, so there is scope to design and manage forest plantations deliberately for water use efficiency. …

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Impact Of High-Order Surface Plasmon Modes Of Metal Nanoparticles On Enhancement Of Optical Emission, Greg Sun, Jacob B. Khurgin, C. C. Yang Oct 2009

Impact Of High-Order Surface Plasmon Modes Of Metal Nanoparticles On Enhancement Of Optical Emission, Greg Sun, Jacob B. Khurgin, C. C. Yang

Physics Faculty Publications

We consider the impact of high-order surface plasmon modes supported by the metal nanoparticles on the efficiency enhancement of optical emission. Using the example of Au nanosphere embedded in the GaN dielectric, we show that for an emitter with certain original radiative efficiency, placing the emitter too close to the metal sphere does not always produce additional enhancement. Thus our model provides analytical treatment of the luminescence quenching and can be used to optimize both nanoparticle size and its separation from the emitter to yield maximum enhancement.

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M.G. Michael And K. Michael (2009). "Uberveillance: Definition" In Ed. S. Butler, Fifth Edition Of The Macquarie Dictionary (Australia's National Dictionary, Sydney University), P. 1094, Susan Butler, M.G. Michael, K. Michael Oct 2009

M.G. Michael And K. Michael (2009). "Uberveillance: Definition" In Ed. S. Butler, Fifth Edition Of The Macquarie Dictionary (Australia's National Dictionary, Sydney University), P. 1094, Susan Butler, M.G. Michael, K. Michael

Professor Katina Michael

No abstract provided.

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The Science Behind Climate Change: A Journey To Reedy Glacier, Brenda L. Hall, Molly Schauffler Oct 2009

The Science Behind Climate Change: A Journey To Reedy Glacier, Brenda L. Hall, Molly Schauffler

University of Maine Office of Research Administration: Grant Reports

This Communicating Research to Public Audiences project focuses on the Reedy Glacier Antarctic research of Brenda Hall (OPP 0229034) and its relevance to the residents of and visitors to Maine. Collaborators include the University of Maine, the Maine Discovery Museum, the Acadia National Park and Cadillac Mountain Sports (an environmentally active retail company with several stores around the state). The primary deliverable is the development of an interactive software program that presents information and experiences in a two-tiered concept approach -- on the Reedy Glacier and its connection to Maine and on the process of science. The software is being …

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Giant Surface-Plasmon-Induced Drag Effect (Spider) In Metal Nanowires, Maxim Durach, Anastasia Rusina, Mark I. Stockman Oct 2009

Giant Surface-Plasmon-Induced Drag Effect (Spider) In Metal Nanowires, Maxim Durach, Anastasia Rusina, Mark I. Stockman

Anastasia Rusina

Here, for the first time we predict a giant surface-plasmon-induced drag-effect rectification (SPIDER), which exists under conditions of the extreme nanoplasmonic confinement. In nanowires, this giant SPIDER generates rectified THz potential differences up to 10 V and extremely strong electric fields up to ∼105–106  V/cm. The giant SPIDER is an ultrafast effect whose bandwidth for nanometric wires is ∼20  THz. It opens up a new field of ultraintense THz nanooptics with wide potential applications in nanotechnology and nanoscience, including microelectronics, nanoplasmonics, and biomedicine.

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An Approximation Approach To Eigenvalue Intervals For Singular Boundary Value Problems With Sign Changing And Superlinear Nonlinearities, Haishen Lu, Ravi P. Agarwal, Donal O'Regan Oct 2009

An Approximation Approach To Eigenvalue Intervals For Singular Boundary Value Problems With Sign Changing And Superlinear Nonlinearities, Haishen Lu, Ravi P. Agarwal, Donal O'Regan

Mathematics and System Engineering Faculty Publications

This paper studies the eigenvalue interval for the singular boundary value problem u″ = g (t, u) + λ h (t, u), t ∈(0, 1),u (0) = 0 = u (1), where g + h may be singular at u = 0, t = 0, 1, and may change sign and be superlinear at u = + ∞. The approach is based on an approximation method together with the theory of upper and lower solutions. Copyright © 2009 Haishen Lü et al.

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3d Reconstruction And Visualization Of A Hovering Dragonfly, Christopher Koehler, Thomas Wischgoll, Haibo Dong, Zachary Gaston, Hui Wan Oct 2009

3d Reconstruction And Visualization Of A Hovering Dragonfly, Christopher Koehler, Thomas Wischgoll, Haibo Dong, Zachary Gaston, Hui Wan

Computer Science and Engineering Faculty Publications

No abstract provided.

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A Cisco-Based Proposal For Arne Core Routing Infrastructure, Ingrimar James Oct 2009

A Cisco-Based Proposal For Arne Core Routing Infrastructure, Ingrimar James

Regis University Student Publications (comprehensive collection)

Systems Engineering and Application Development (SEAD) Practicum provides opportunities for students to engage in proposing, designing, building and testing various projects related to information technology. There are several ongoing projects designed to upgrade, improve or revamp some aspect of the Academic Research Network, generally referred to as ARNe, and services or applications that are a part of its architecture. Regis University is in the process of replacing their current architecture and equipment that forms the core of ARNe in order to facilitate further upgrades and new projects within various aspects of ARNe. This paper examines and proposes a Cisco-based routing …

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A Survey Of The Semantic Specification Of Sensors, Michael Compton, Cory Andrew Henson, Laurent Lefort, Holger Neuhaus, Amit P. Sheth Oct 2009

A Survey Of The Semantic Specification Of Sensors, Michael Compton, Cory Andrew Henson, Laurent Lefort, Holger Neuhaus, Amit P. Sheth

Kno.e.sis Publications

Semantic sensor networks use declarative descriptions of sensors promote reuse and integration, and to help solve the difficulties of installing, querying and maintaining complex, heterogeneous sensor networks. This paper reviews the state of the art for the semantic specification of sensors, one of the fundamental technologies in the semantic sensor network vision. Twelve sensor ontologies are reviewed and analysed for the range and expressive power of their concepts. The reasoning and search technology developed in conjunction with these ontologies is also reviewed, as is technology for annotating OGC standards with links to ontologies. Sensor concepts that cannot be expressed accurately …

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Continuous Phase Amplification With A Sagnac Interferometer, David J. Starling, P. Ben Dixon, Nathan S. Williams, Andrew N. Jordan, John C. Howell Oct 2009

Continuous Phase Amplification With A Sagnac Interferometer, David J. Starling, P. Ben Dixon, Nathan S. Williams, Andrew N. Jordan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We describe a phase-amplification technique using a Sagnac interferometer. We monitor the relative phase between two paths of a precisely misaligned interferometer by measuring the average position of a split-Gaussian mode in the dark port. Although we monitor only the dark port, we show that the signal varies linearly with phase and that we can obtain similar sensitivity to balanced homodyne detection. We derive the source of the amplification using classical wave optics.

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Wavepacket Approach To The Cumulative Reaction Probability Within The Flux Operator Formalism, Sophya Garashchuk, Tijo Vazhappilly Oct 2009

Wavepacket Approach To The Cumulative Reaction Probability Within The Flux Operator Formalism, Sophya Garashchuk, Tijo Vazhappilly

Faculty Publications

Expressions for the singular flux operator eigenfunctions and eigenvalues are given in terms of the Dirac δ-function representable as a localized Gaussian wavepacket. This functional form enables computation of the cumulative reaction probability N(E) from the wavepacket time-correlation functions. The Gaussian based form of the flux eigenfunctions, which is not tied to a finite basis of a quantum-mechanical calculation, is particularly useful for approximate calculation of N(E) with the trajectory based wavepacket propagation techniques. Numerical illustration is given for the Eckart barrier using the conventional quantum-mechanical propagation and the quantum trajectory dynamics with the approximate quantum potential. N(E) converges with …

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Breaking From Tradition: India And The Path To Development, Angel M. Newsom Oct 2009

Breaking From Tradition: India And The Path To Development, Angel M. Newsom

Regis University Student Publications (comprehensive collection)

"How could a country with more than 300 million illiterate people also have the kind of scientific human resources that bring some of the world's largest corporations to base their R&D labs in India?" (Tripathi, 2007, p.68). This question acknowledges the coexistence of two vastly different worlds within one country. On one hand, India is making significant progress on the path to becoming a developed country;one that can provide the basic fundamentals of living for its citizens while sustaining progressive economic growth; on the other hand, it must overcome challenges to this goal that relate to a crumbling infrastructure, poverty, …

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Designing Short Term Trading Systems With Artificial Neural Networks, Bruce Vanstone, Gavin Finnie, Tobias Hahn Oct 2009

Designing Short Term Trading Systems With Artificial Neural Networks, Bruce Vanstone, Gavin Finnie, Tobias Hahn

Tobias Hahn

There is a long established history of applying Artificial Neural Networks (ANNs) to financial data sets. In this paper, the authors demonstrate the use of this methodology to develop a financially viable, short-term trading system. When developing short-term systems, the authors typically site the neural network within an already existing non-neural trading system. This paper briefly reviews an existing medium-term long-only trading system, and then works through the Vanstone and Finnie methodology to create a short-term focused ANN which will enhance this trading strategy. The initial trading strategy and the ANN enhanced trading strategy are comprehensively benchmarked both in-sample and …

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Analisis Data Riskesdas 2007/2008: Kontribusi Karakteristik Ibu Terhadap Status Imunisasi Anak Di Indonesia, Sutanto Priyo Hastono Oct 2009

Analisis Data Riskesdas 2007/2008: Kontribusi Karakteristik Ibu Terhadap Status Imunisasi Anak Di Indonesia, Sutanto Priyo Hastono

Kesmas

Cakupan imunisasi terbukti dapat menurunkan secara signifikan kejadian kesakitan dan kematian yang diakibatkan penyakit tersebut, tetapi di Indonesia cakupan tersebut tergolong rendah. Tujuan penelitian adalah mengetahui hubungan karakteristik ibu dengan status imunisasi anak di Indonesia. Disain yang digunakan dalam penelitian adalah potong lintang dengan sampel anak yang berumur antara 1-2 tahun yang tinggal di wilayah Indonesia. Sumber data sekunder yang digunakan adalah Riskesdas Depkes tahun 2007/2008. Proporsi anak usia 12-24 bulan yang mendapat imunisasi lengkap adalah 56,2 % (95% CI :55,1-57,3). Pendidikan ibu dan pendidikan suami ditemukan berhubungan secara bermakna dengan status imunisasi dasar pada anak. Hasil analisis multilevel menemukan …

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Supersymmetric Lattices - A Brief Introduction, Simon Catterall Oct 2009

Supersymmetric Lattices - A Brief Introduction, Simon Catterall

Physics - All Scholarship

Recently, new theoretical ideas have allowed the construction of lattice actions which are explicitly invariant under one or more supersymmetries. These theories are local and free of doublers and in the case of Yang-Mills theories also possess exact gauge invariance. In this talk these ideas are reviewed with particular emphasis being placed on {\cal N}=4 super Yang-Mills theory.

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Chemistry In Second Life, Andrew Lang, Jean-Claude Bradley Oct 2009

Chemistry In Second Life, Andrew Lang, Jean-Claude Bradley

College of Science and Engineering Faculty Research and Scholarship

This review will focus on the current level on chemistry research, education, and visualization possible within the multi-user virtual environment of Second Life. We discuss how Second Life has been used as a platform for the interactive and collaborative visualization of data from molecules and proteins to spectra and experimental data. We then review how these visualizations can be scripted for immersive educational activities and real-life collaborative research. We also discuss the benefits of the social networking affordances of Second Life for both chemists and chemistry students.

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Chemistry In Second Life, Andrew Lang, Jean-Claude Bradley Oct 2009

Chemistry In Second Life, Andrew Lang, Jean-Claude Bradley

College of Science and Engineering Faculty Research and Scholarship

This review will focus on the current level on chemistry research, education, and visualization possible within the multi-user virtual environment of Second Life. We discuss how Second Life has been used as a platform for the interactive and collaborative visualization of data from molecules and proteins to spectra and experimental data. We then review how these visualizations can be scripted for immersive educational activities and real-life collaborative research. We also discuss the benefits of the social networking affordances of Second Life for both chemists and chemistry students.

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