Physical Sciences and Mathematics Commons^™

The Webt Campaign On The Blazar 3c 279 In 2006, Markus Böttcher, Jeff W. Robertson, Stéphane Vennes

Aerospace, Physics, and Space Science Faculty Publications

The quasar 3C 279 was the target of an extensive multiwavelength monitoring campaign from 2006 January through April. An optical-IR-radio monitoring campaign by the Whole Earth Blazar Telescope (WEBT) collaboration was organized around target-of-opportunity X-ray and soft γ-ray observations with Chandra and INTEGRAL in 2006 mid-January, with additional X-ray coverage by RXTE and Swift XRT. In this paper we focus on the results of the WEBT campaign. The source exhibited substantial variability of optical flux and spectral shape, with a characteristic timescale of a few days. The variability patterns throughout the optical BVRI bands were very closely correlated with each …

Decomposition-Based Recovery Of Absorbers In Turbid Media, S D. Campbell, I L. Goodin, S D. Grobe, Qichang Su, Rainer Grobe

Faculty publications – Physics

We suggest that the concept of the point-spread function traditionally used to predict the blurred image pattern of various light sources embedded inside turbid media can be generalized under certain conditions to predict also the presence and location of spatially localized absorbing inhomogeneities based on shadow point-spread functions associated with each localized absorber in the medium. The combined image obtained from several absorbers can then be decomposed approximately into the arithmetic sums of these individual shadow point-spread functions with suitable weights that can be obtained from multiple-regression analysis. This technique permits the reconstruction of the location of absorbers.

Hunting For Hydrothermal Vents Along The Galápagos Spreading Center, Rachel M. Haymon, Edward T. Baker, Joseph A. Resing, Scott M. White, Ken C. Macdonald

Faculty Publications

No abstract provided.

Bidimensional Pr Qmf With Fir Filters, Jian-Ao Lian

Applications and Applied Mathematics: An International Journal (AAM)

Multidimensional perfect reconstruction (PR) quadrature mirror filter (QMF) banks with finite impulse response (FIR) filters induced from systems of biorthogonal multivariate scaling functions and wavelets are investigated. In particular, bivariate scaling functions and wavelets with dilation as an expansive integer matrix whose determinant is two in absolute value are considered. Demonstrative quincunxial examples are explicitly given and new FIR filters are constructed.

On Mathematical Modeling, Nonlinear Properties And Stability Of Secondary Flow In A Dendrite Layer, D. N. Riahi

Applications and Applied Mathematics: An International Journal (AAM)

This paper studies instabilities in the flow of melt within a horizontal dendrite layer with deformed upper boundary and in the presence or absence of rotation during the solidification of a binary alloy. In the presence of rotation, it is assumed that the layer is rotating about a vertical axis at a constant angular velocity. Linear and weakly nonlinear stability analyses provide results about various flow features such as the critical mode of convection, neutral stability curve, preferred flow pattern and the solid fraction distribution within the dendrite layer. The preferred shape of the deformed upper boundary of the layer, …

X-Rays From Magnetically Channeled Winds Of Ob Stars, In 'Magnetic Massive Stars', David H. Cohen

Physics & Astronomy Faculty Works

OB stars with strong radiation-driven stellar winds and large-scale magnetic fields generate strong and hard X-ray emission via the Magnetically Channeled Wind Shock (MCWS) mechanism. In this brief paper, I describe four separate X-ray diagnostics of the MCWS mechanism in OB stars, with applications to the prototype young O star, theta-1 Ori C.

Predicting Magnetospheric Dynamics With A Coupled Sun‐To‐Earth Model: Challenges And First Results, V. G. Merkin, M. J. Owens, Harlan E. Spence, W. J. Hughes, J. M. Quinn

Physics & Astronomy

[1] Results from the first Sun-to-Earth coupled numerical model developed at the Center for Integrated Space Weather Modeling are presented. The model simulates physical processes occurring in space spanning from the corona of the Sun to the Earth's ionosphere, and it represents the first step toward creating a physics-based numerical tool for predicting space weather conditions in the near-Earth environment. Two 6- to 7-d intervals, representing different heliospheric conditions in terms of the three-dimensional configuration of the heliospheric current sheet, are chosen for simulations. These conditions lead to drastically different responses of the simulated magnetosphere-ionosphere system, emphasizing, on the one …

Weak Ferromagnetism In Fe₁₋ₓcoₓsb₂, Rongwei Hu, Raphäel P. Hermann, Fernande Grandjean, Yong Jae Lee, John B. Warren, Vesna F. Mitrovic, Cedomir Petrovic

Chemistry Faculty Research & Creative Works

Weak ferromagnetism in Fe_1-xCo_xSb₂ is studied by magnetization and Mössbauer measurements. A small spontaneous magnetic moment of the order of ~ 10^-3µ_B appears along the b axis for 0.2 ≤ x ≤ 0.4. Based on a structural analysis, we argue against extrinsic sources of weak ferromagnetism. We discuss our results in the framework of the nearly magnetic electronic structure of the parent compound FeSb₂.

Immediate Implant Placement In Extraction Sites With Periapical Lesions: A Retrospective Study, Yuan-Lung Hung

Loma Linda University Electronic Theses, Dissertations & Projects

Immediate implant placement into fresh extraction sites has become a relatively routine clinical procedure with a favorable prognosis. However, immediate placement into extraction sockets with lesions has not been extensively documented in humans. Therefore, the purpose of this study was to retrospectively determine the survival rate of implants placed into extraction sockets with visible periapical lesions.

Patient charts of 544 immediately placed implants from Loma Linda University School of Dentistry, Center for Prosthodontics and Implant Dentistry were examined. Eighty-six of the 544 implants had been placed immediately into extraction sockets with periapical lesions and they were included in this study. …

Building Effective Community Participation And Stakeholder Partnerships To Promote Positive Change In The Southern Ethiopian Rangelands, D. Layne Coppock, Solomon Desta, Getachew Gebru, Seyoum Tezera, Dadi Amosha

Environment and Society Faculty Publications

Recently there has been increased recognition that authentic community participation and creating strong inter-institutional partnerships are both important in the process of capacity building, generating innovation, and sustaining development achievements in rural Africa. Here we summarize a process of community participation and formation of institutional partnerships in support of pastoral risk-management interventions over the past seven years on the Borana Plateau. Community involvement has been stimulated using Participatory Rural Appraisal (PRA) methods. This has resulted in the proliferation of pastoral collective-action groups that have diversified livelihoods, engaged markets, and improved incomes. Implementing and sustaining positive change, however, has also been …

Diffusion Of Collective-Action Innovations Among Pastoralists In Liben District, Ethiopia, D. Layne Coppock, Solomon Desta, Getachew Gebru, Getachew Kassa, Seyoum Tezera

Environment and Society Faculty Publications

In 2001 PARIMA and her partners began to create collective-action groups among illiterate, settled pastoralists in Ethiopia. These groups—soon dominated by women—focused on savings-led microfinance, small business activity, and livestock marketing to increase incomes and diversify livelihoods. Fifty-nine groups with over 2,100 members were formed using intensive training methods, and they have subsequently merged into legally recognized cooperatives. We regard this approach as successful and sustainable. We were curious, however, if “the word has spread” and collective-action has spontaneously arisen beyond our immediate project area. Preliminary findings from recent surveys of settlements in Liben District indicate that diffusion of collective-action …

Collective Action Among Agro-Pastoralists In Baringo District, Kenya: Identifying And Nurturing The Entrepreneurs, D. Layne Coppock, Mark N. Mutinda, Stellamaris K. Muthoka, Abdillahi A. Aboud

Environment and Society Faculty Publications

The rural population of Baringo District in the Rift Valley of north-central Kenya faces numerous challenges including widespread environmental degradation and poverty. The region has endured decades of failed development projects, proliferation of food aid, and has been studied extensively. We have recently undertaken a different approach focused on bottom-up participatory action research and outreach among the Il Chamus and Tugen ethnic communities. The objective is to explore new ways to empower local people via provision of information, novel experiences, and initial access to resources to allow them to envision an alternative future and implement their own activities to better-manage …

Stakeholder Alliance Facilitates Re-Introduction Of Prescribed Fire On The Borana Plateau Of Southern Ethiopia, D. Layne Coppock, Getachew Gebru, Solomon Desta, Lemma Gizachew, Dadhi Amosha, Feyissa Taffa

Environment and Society Faculty Publications

The implementation of a new prescribed fire program to restore bush-encroached rangelands in southern Ethiopia—and hence increase herbaceous forage supplies for livestock—is given as an example of an integrated action involving multiple institutions to address resource-management problems. The resumption of planned fire—traditionally conducted over hundreds of years by pastoralists until the 1970s—was preceded by key activities including mobilization of the pastoral community, review of government proclamations regarding use of fire, interaction with policy makers, capacity building among pastoralists and agency personnel on how to implement and manage planned fires, development of an overall prescribed burn plan, selection of geo-referenced sites, …

Unfolding Polyhedra Via Cut-Tree Truncation, Alex Benton, Joseph O'Rourke

Computer Science: Faculty Publications

We prove that an infinite class of convex polyhedra, produced by restricted vertex truncations, always unfold without overlap. The class includes the "domes," providing a simpler proof that these unfold without overlap.

The Slider-Pinning Problem, Audrey Lee, Ileana Streinu, Louis Theran

Computer Science: Faculty Publications

A Laman mechanism is a flexible planar bar-and-joint framework with m ≤ 2n-3 edges and exactly k = 2n-m degrees of freedom. The slider-pinning problem is to eliminate all the degrees of freedom of a Laman mechanism, in an optimal fashion, by individually fixing x or y coordinates of vertices. We describe two easy to implement O(n2) time algorithms.

Biological Assessment On The Operation Of Glen Canyon Dam And Proposed Experimental Flows For The Colorado River Below Glen Canyon Dam During The Years 2008-2012, U.S. Department Of The Interior, Bureau Of Reclamation, Upper Colorado Region, Salt Lake City, Utah

All U.S. Government Documents (Utah Regional Depository)

This document serves as the biological assessment for the Bureau of Reclamation's (Reclamation) re-initiation of consultation on the operation of Glen Canyon Dam and proposed experimental flows for the Colorado River below Glen Canyon Dam during the years 2008-2012. It is prepared by Reclamation as part of its compliance with the Endangered Species Act of 1973 (ESA), 87 Stat. 884, as amended, 16 U.S.C. section 1531 et seq. This document is designed to facilitate compliance with Sections 7 and 9 of the ESA with respect to potential effects to listed species within the United States (US).

Location Update Versus Paging Trade-Off In Cellular Networks: An Approach Based On Vector Quantization, Abhishek Roy, Archan Misra, Sajal K. Das

Research Collection School Of Computing and Information Systems

In this paper we propose two information-theoretic techniques for efficiently trading off the location update and paging costs associated with mobility management in wireless cellular networks. Previous approaches attempt to always accurately convey a mobile's movement sequence and hence, cannot reduce the signaling cost below the entropy bound. Our proposed techniques, however, exploit rate-distortion theory to arbitrarily reduce the update cost, at the expense of an increase in the corresponding paging overhead. To this end, we describe two location tracking algorithms, based on spatial quantization and temporal quantization, which first quantize the movement sequence into a smaller set of codewords, …

Constraints On An Optical Afterglow And On Supernova Light Following The Short Burst Grb 050813, P. Ferreo, S. F. Sanchez, D. A. Kann, S. Klose, J. Greiner, J. Gorosabel, Dieter H. Hartmann, A. A. Henden, P. Møller, E. Palazzi

Publications

We report early follow-up observations of the error box of the short burst GRB 050813 using the telescopes at Calar Alto and Observatorio Sierra Nevada, followed by deep VLT FORS2 I-band observations obtained under very good seeing conditions 5.7 and 11.7 days after the event. Neither a fading afterglow nor a rising SN component was found, so the potential GRB host galaxy has not been identified based on a comparison of the two VLT images taken at different epochs. We discuss whether any of the galaxies present in the original 1000 XRTerror circle could be the host.In anycase, the optical …

Combining Geospatial And Temporal Ontologies, Kripa Joshi

Electronic Theses and Dissertations

Publicly available ontologies are growing in number at present. These ontologies describe entities in a domain and the relations among these entities. This thesis describes a method to automatically combine a pair of orthogonal ontologies using cross products. A geospatial ontology and a temporal ontology are combined in this work. Computing the cross product of the geospatial and the temporal ontologies gives a complete set of pairwise combination of terms from the two ontologies. This method offers researchers the benefit of using ontologies that are already existing and available rather than building new ontologies for areas outside their scope of …

Linking Moving Object Databases With Ontologies, Kraig King

Electronic Theses and Dissertations

This work investigates the supporting role of ontologies for supplementing the information contained in moving object databases. Details of the spatial representation as well as the sensed location of moving objects are frequently stored within a database schema. However, this knowledge lacks the semantic detail necessary for reasoning about characteristics that are specific to each object. Ontologies contribute semantic descriptions for moving objects and provide the foundation for discovering similarities between object types. These similarities can be drawn upon to extract additional details about the objects around us. The primary focus of the research is a framework for linking ontologies …

Technical Evaluation Of Hardwood Biorefinery Using The "Near-Neutral" Hemicellulose Extraction Process, Haibo Mao

Electronic Theses and Dissertations

A technical analysis was performed for a new process that produces ethanol and acetic acid from hardwood in addition to bleached hardwood Kraft pulp. The new process, termed the "near neutral" hemicellulose extraction process, involves the extraction of wood hemicellulose using green liquor prior to conventional Kraft pulping. This thesis assumes that the new process is located at an existing kraft pulp mill. Ancillary unit operations in the process include hydrolysis of the extracted carbohydrates using sulfuric acid, filtration of the extract to remove lignin that was extracted with the carbohydrates, liquid-liquid extraction of acetic acid and by-product furfural, liming …

Impact Of The Equation Of State In Core-Collapse Supernovae, Mark Lewis Baird

Masters Theses

One of the key ingredients to the core collapse supernova mechanism is the physics of matter at or near nuclear density. Included in simulations as part of the Equation of State (EoS), nuclear repulsion experienced at high densities is responsible for the bounce shock, which initially causes the outer envelope of the supernova to expand, as well as determining the structure of the newly formed proto-neutron star. Recent years have seen renewed interest in this fundamental piece of supernova physics, resulting in several promising candidate EoS parameterizations. We will present the impact of several of their variations in the nuclear …

Evaluation Of Remote Trap Monitors

United States Department of Agriculture Wildlife Services: Staff Publications

Can trap monitors save Wildlife Services (WS) specialists time and money by increasing the efficiency of trap checks? To find out, WS scientists and field specialists evaluated the use of remote trap monitors. In 2006, WS personnel evaluated the effectiveness of two remote monitoring devices to alert wildlife specialists when an animal is captured in a trap. The devices, which can be used with any type of trap, consist of small radio transmitters that emit unique pulse rates when an animal is captured. WS personnel tested the device on a variety of wildlife species using several different types of traps …

What Allows Teachers To Extend Student Thinking During Whole-Group Discussions, Nesrin Cengiz

Dissertations

Research indicates that extending students' mathematical thinking during whole-group discussions is challenging, even for the most experienced teachers. That is, it is challenging for teachers to help students move beyond their initial mathematical observations and solutions during whole-group discussions. To better understand this phenomena, the teaching of six experienced elementary school teachers, who had been teaching aStandards-based curriculum for several years and had participated in a multi-year professional development project focused on that curriculum, is explored in this study. In particular, two issues are addressed: what it looks like to extend student thinking during whole-group discussions and how …

Adsorption Of Lead On Single And Mixed Solid Systems, Soumya Das

Dissertations

Metal oxy-hydroxides and phyllosilicate minerals play a significant role in the fate and transport of heavy metals in the environment (Bertsch and Seaman, 1999). Chemical speciation of metals affects their bioavailability and chemical reactivity (Stumm and Morgan, 1996). Surface complexation models (SCMs) based on equilibrium thermodynamic principles have been successfully used to quantify adsorption of heavy metals on pure solid minerals, including phyllosilicates and oxy-hydroxides. For natural sediments with mixed mineralogy, Davis et al. (1998) suggested two different SCM approaches, namely, the component additivity and generalized composite models. In this study, adsorption of lead on pure HFO, silica and kaolinite …

The John Muir Newsletter, Winter 2007/2008, The John Muir Center For Environmental Studies

Muir Center Newsletters (1981-2015)

Muir SLETTEB YfeRSnY OF THE PACIFIC, STOCKTON, CA Volume 18, Number 1 Winter 2007/20081 John Muir's World Tour (part VI) Introduction by W.R. Swagerty Director, John Muir Center In this, the sixth and final segment of John Muir's World Tour, 1903-1904, we complete his journey from March 2 to May 27, 1904 from open waters in the Tasman Sea to San Francisco. Muir continues writing in his Collin's Paragon Diary, 1904, purchased in Australia and reflecting the calendar for the Southern Hemisphere. This form of "journal" allowed the author to enter one page per day. If he needed more space, …

Shake & Bake: Dual-Use Chemicals, Contexts, And The Illegality Of American White Phosphorus Attacks In Iraq, Joseph D. Tessier

The University of New Hampshire Law Review

[Excerpt] “On November 29, 2005, in a Department of Defense press conference with Secretary of Defense Donald Rumsfeld and Gen. Peter Pace, Chairman of the Joint Chiefs of Staff, General Pace stated that white phosphorus “is a legitimate tool of the military,” and can be used for illumination, smoke, and incendiary purposes. Incredibly, the Department of Defense released an addendum to the press conference clarifying that white phosphorus was not used as an incendiary weapon. According to General Pace, “it was well within the law of war to use white phosphorus . . . for marking and screening.” This was …

Materials Research & Manufacturing Section, Betsy Aldridge

Sci-Tech News

No abstract provided.

2007 Annual Conference Reports

Sci-Tech News

No abstract provided.

Chemistry Division, A. Ben Wagner

Sci-Tech News

No abstract provided.