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2009

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Articles 4411 - 4440 of 7615

Full-Text Articles in Physical Sciences and Mathematics

Properties Of Warm Absorbers In Active Galaxies: A Systematic Stability Curve Analysis, Susmita Chakravorty, Ajit K. Kembhavi, Martin Elvis, Gary J. Ferland Jan 2009

Properties Of Warm Absorbers In Active Galaxies: A Systematic Stability Curve Analysis, Susmita Chakravorty, Ajit K. Kembhavi, Martin Elvis, Gary J. Ferland

Physics and Astronomy Faculty Publications

Signatures of warm absorbers are seen in soft X-ray spectra of about half of all type 1 Seyfert galaxies observed and in some quasars and blazars. We use the thermal equilibrium curve to study the influence of the shape of the ionizing continuum, density and the chemical composition of the absorbing gas on the existence and nature of the warm absorbers. We describe circumstances in which a stable warm absorber can exist as a multiphase medium or one with continuous variation in pressure. In particular, we find the following results: (i) the warm absorber exists only if the spectral index …

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3d Reconstruction Using Multi-View Imaging System, Conglin Huang Jan 2009

3d Reconstruction Using Multi-View Imaging System, Conglin Huang

University of Kentucky Master's Theses

This thesis presents a new system that reconstructs the 3D representation of dental casts. To maintain the integrity of the 3D representation, a standard model is built to cover the blind spots that the camera cannot reach. The standard model is obtained by scanning a real human mouth model with a laser scanner. Then the model is simplified by an algorithm which is based on iterative contraction of vertex pairs. The simplified standard model uses a local parametrization method to obtain the curvature information. The system uses a digital camera and a square tube mirror in front of the camera …

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Use Of Surface Geophysical Techniques To Locate A Karst Conduit In The Cane Run - Royal Spring Basin, Kentucky, Ganesh N. Tripathi Jan 2009

Use Of Surface Geophysical Techniques To Locate A Karst Conduit In The Cane Run - Royal Spring Basin, Kentucky, Ganesh N. Tripathi

University of Kentucky Master's Theses

Groundwater flow in karst terrains is difficult to map because it can be concentrated through conduits that do not necessarily coincide with the surface features. We applied electrical resistivity (ER) and self-potential (SP) techniques at three sites to locate an inferred trunk conduit feeding a major spring in the Inner Bluegrass region of Kentucky. Royal Spring is the primary water supply for the city of Georgetown; the upper part of its basin coincides with the Cane Run watershed. ER and SP profiles were perpendicular to the inferred trunk conduit orientation. ER profiles (972 m total length) were measured using a …

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Bedrock Mapping Of The Winchendon (1:25,000) Quadrangle (Ma-Nh): Evidence For Discontinous Deformation Along The Bronson Hill-Central Maine Boundary Zone, Timothy M. O'Brien Jan 2009

Bedrock Mapping Of The Winchendon (1:25,000) Quadrangle (Ma-Nh): Evidence For Discontinous Deformation Along The Bronson Hill-Central Maine Boundary Zone, Timothy M. O'Brien

University of Kentucky Master's Theses

Bedrock geology of the Winchendon quadrangle is divided into two zones based on structures and lithology. The eastern zone consists of tightly folded Silurian Rangeley and Paxton metasediments and pegmatites. Planar, NNE-SSW striking, W dipping foliations are characterized by alternating phyllosilicate-rich and leucosome layers. Fold axes of tight to isoclinal upright and recumbent folding are parallel to SSW-NNE shallowly plunging sillimanite, quartz and muscovite lineations. In the western zone Rangeley schists were intruded by Devonian Hardwick and Coys Hill and Fitzwilliam plutons. Planar NNE-SSW striking foliations dip shallowly to steeply west. Fold axes of tight-to-isoclinal asymmetric to recumbent folds plunge …

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Structural Geology Of The Transylvania Fault Zone In Bedford County, Pennsylvania, Elizabeth Lauren Dodson Jan 2009

Structural Geology Of The Transylvania Fault Zone In Bedford County, Pennsylvania, Elizabeth Lauren Dodson

University of Kentucky Master's Theses

Transverse zones cross strike of thrust-belt structures as large-scale alignments of cross-strike structures. The Transylvania fault zone is a set of discontinuous right-lateral transverse faults striking at about 270º across Appalachian thrust-belt structures along 40º N latitude in Pennsylvania. Near Everett, Pennsylvania, the Breezewood fault terminates with the Ashcom thrust fault. The Everett Gap fault terminates westward with the Hartley thrust fault. Farther west, the Bedford fault extends westward to terminate against the Wills Mountain thrust fault. The rocks, deformed during the Alleghanian orogeny, are semi-independently deformed on opposite sides of the transverse fault, indicating fault movement during folding and …

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Integration Of An Extended Octagonal Ring Transducer And Soil Coulterometer For Identifying Soil Compaction, Santosh K. Pitla, Larry G. Wells, Scott A. Shearer Jan 2009

Integration Of An Extended Octagonal Ring Transducer And Soil Coulterometer For Identifying Soil Compaction, Santosh K. Pitla, Larry G. Wells, Scott A. Shearer

Biosystems and Agricultural Engineering Faculty Publications

The soil coulterometer is an "on-the-go" electro-mechanical system which collects impedance force data at multiple depths using an oscillating coulter. During the initial testing (summer 2006), only vertical soil impedance force data was collected using a pressure sensor. To improve the performance of the coulterometer, an extended octagonal ring transducer was integrated into the system to collect both the horizontal and vertical impedance forces given by the soil. In the summer of 2007, data was collected using the revised sensor from a typical central Kentucky field setting in a 0.8-ha (2-acre) plot. Four passes were made with the coulterometer. Seventy …

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Application Of Hertz Vector Diffraction Theory To The Diffraction Of Focused Gaussian Beams And Calculations Of Focal Parameters, Glen D. Gillen, Kendra Baughman, Shekhar Guha Jan 2009

Application Of Hertz Vector Diffraction Theory To The Diffraction Of Focused Gaussian Beams And Calculations Of Focal Parameters, Glen D. Gillen, Kendra Baughman, Shekhar Guha

Physics

Hertz vector diffraction theory is applied to a focused TEM00 Gaussian light field passing through a circular aperture. The resulting theoretical vector field model reproduces plane-wave diffractive behavior for severely clipped beams, expected Gaussian beam behavior for unperturbed focused Gaussian beams as well as unique diffracted-Gaussian behavior between the two regimes. The maximum intensity obtainable and the width of the beam in the focal plane are investigated as a function of the clipping ratio between the aperture radius and the beam width in the aperture plane.

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High-Temperature Deformation During Continental-Margin Subduction & Exhumation: The Ultrahigh-Pressure Western Gneiss Region Of Norway, Bradley R. Hacker, Torgeir B. Andersen, Scott Johnston, Andrew R.C. Kylander-Clark, Emily M. Peterman, Emily O. Walsh, David Young Jan 2009

High-Temperature Deformation During Continental-Margin Subduction & Exhumation: The Ultrahigh-Pressure Western Gneiss Region Of Norway, Bradley R. Hacker, Torgeir B. Andersen, Scott Johnston, Andrew R.C. Kylander-Clark, Emily M. Peterman, Emily O. Walsh, David Young

Physics

A new dataset for the high-pressure to ultrahigh-pressure Western Gneiss Region allows the definition of distinct structural and petrological domains. Much of the study area is an E-dipping homocline with E-plunging lineations that exposes progressively deeper, more strongly deformed, more eclogite-rich structural levels westward. Although eclogites crop out across the WGR, Scandian deformation is weak and earlier structures are well preserved in the southeastern half of the study area. The Scandian reworking increases westward, culminating in strong Scandian fabrics with only isolated pockets of older structures; the dominant Scandian deformation was coaxial E–W stretching. The sinistrally sheared Møre–Trøndelag Fault Complex …

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Magnetosomes And Magneto-Aerotaxis, Richard B. Frankel, Dennis A. Bazylinski Jan 2009

Magnetosomes And Magneto-Aerotaxis, Richard B. Frankel, Dennis A. Bazylinski

Physics

Magnetotactic bacteria orient and migrate along geomagnetic field lines. Magneto-aerotaxis increases the efficiency of respiring microaerophilic cells to efficiently find and maintain a position at a preferred microaerobic oxygen concentration. Magneto-aerotaxis could also facilitate access to regions of higher nutrient and electron acceptor concentration via periodic excursions above and below the preferred oxygen concentration level.

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Computing Prime Harmonic Sums, Eric Bach, Dominic Klyve, Jonathan P. Sorenson Jan 2009

Computing Prime Harmonic Sums, Eric Bach, Dominic Klyve, Jonathan P. Sorenson

Scholarship and Professional Work - LAS

We discuss a method for computing Σ �≤� 1/�, using time about �2/3 and space about �1/3. It is based on the Meissel-Lehmer algorithm for computing the prime-counting function �(�), which was adapted and improved by Lagarias, Miller, and Odlyzko. We used this algorithm to determine the first point at which the prime harmonic sum first crosses.

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The Hamiltonian Index Of Graphs, Yi Hong, Jian-Liang Lin, Zhi-Sui Tao, Zhi-Hong Chen Jan 2009

The Hamiltonian Index Of Graphs, Yi Hong, Jian-Liang Lin, Zhi-Sui Tao, Zhi-Hong Chen

Scholarship and Professional Work - LAS

The Hamiltonian index of a graph G is defined as h ( G ) = min { m : L m ( G ) is Hamiltonian } . In this paper, using the reduction method of Catlin [P.A. Catlin, A reduction method to find spanning Eulerian subgraphs, J. Graph Theory 12 (1988) 29–44], we constructed a graph H ̃ ( m ) ( G ) from G and prove that if h ( G ) ≥ 2 , then h ( G ) = min{ m : H ̃ ( m ) ( G ) has a spanning Eulerian subgraph …

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Methods For The Isolation Of Sensory And Primary Cilia—An Overview, Kimberly A. P. Mitchell, Gabor Szabo, Angela De S. Otero Jan 2009

Methods For The Isolation Of Sensory And Primary Cilia—An Overview, Kimberly A. P. Mitchell, Gabor Szabo, Angela De S. Otero

Faculty Publications and Presentations

Detailed proteomic analyses of mammalian olfactory and rod photoreceptor sensory cilia are now available, providing an inventory of resident ciliary proteins and laying the foundation for future studies of developmental and spatio-temporal changes in the composition of sensory cilia. Cilia purification methods that were elaborated and perfected over several decades were essential for these advances. In contrast, the proteome of primary cilia is yet to be established, because purification procedures for this organelle have been developed only recently. In this chapter we review current techniques for the purification of olfactory and photoreceptor cilia, and evaluate methods designed for the selective …

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Direct Binding Of Cytosolic Ndp Kinases To Membrane Lipids Is Regulated By Nucleotides, Kimberly A. P. Mitchell, Gabor Szabo, Angela De S . Otero Jan 2009

Direct Binding Of Cytosolic Ndp Kinases To Membrane Lipids Is Regulated By Nucleotides, Kimberly A. P. Mitchell, Gabor Szabo, Angela De S . Otero

Faculty Publications and Presentations

In spite of their complete lack of any structural features that characterize membrane proteins, cytosolic nucleoside-diphosphate kinases (NDPKs) have been found repeatedly to associate with membranes. In some instances the recruitment of cytosolic NDPKs to membranes was attributed to interactions with peripheral or integral membrane proteins, but in many cases the mechanism underlying the association of NDPKs with membranes remained unknown. We show here that cytosolic NDPKs bind directly to membrane lipids in a dynamic process that is controlled by its substrates, nucleoside tri- and diphosphates, and can be fully reconstituted with chemically defined, protein-free phospholipids and recombinant NDPK, or …

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Multiple Stable Reference Points In Oyster Populations: Biological Relationships For The Eastern Oyster (Crassostrea Virginica) In Delaware Bay, Eric N. Powell, John M. Klinck, Kathryn A. Ashton-Alcox, John N. Kraeuter Jan 2009

Multiple Stable Reference Points In Oyster Populations: Biological Relationships For The Eastern Oyster (Crassostrea Virginica) In Delaware Bay, Eric N. Powell, John M. Klinck, Kathryn A. Ashton-Alcox, John N. Kraeuter

CCPO Publications

In the first of two companion papers, a 54-yr time series for the oyster population in the New Jersey waters of Delaware Bay was analyzed to develop biological relationships necessary to evaluate maximum sustainable yield (MSY) reference points and to consider how multiple stable points affect reference point-based management. The time series encompassed two regime shifts, one circa 1970 that ushered in a 15-yr period of high abundance, and a second in 1985 that ushered in a 20-yr period of low abundance. The intervening and succeeding periods have the attributes of alternate stable states. The biological relationships between abundance, recruitment, …

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Variations In Sea Surface Roughness Induced By The 2004 Sumatra-Andaman Tsunami, O. A. Godin, V. G. Irisov, R. R. Leben, B. D. Hamlington, G. A. Wick Jan 2009

Variations In Sea Surface Roughness Induced By The 2004 Sumatra-Andaman Tsunami, O. A. Godin, V. G. Irisov, R. R. Leben, B. D. Hamlington, G. A. Wick

CCPO Publications

Observations of tsunamis away from shore are critically important for improving early warning systems and understanding of tsunami generation and propagation. Tsunamis are difficult to detect and measure in the open ocean because the wave amplitude there is much smaller than it is close to shore. Currently, tsunami observations in deep water rely on measurements of variations in the sea surface height or bottom pressure. Here we demonstrate that there exists a different observable, specifically, ocean surface roughness, which can be used to reveal tsunamis away from shore. The first detailed measurements of the tsunami effect on sea surface height …

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A Simple Sn2 Reaction For The Undergraduate Organic Laboratory, John J. Esteb Jan 2009

A Simple Sn2 Reaction For The Undergraduate Organic Laboratory, John J. Esteb

Scholarship and Professional Work - LAS

A simple procedure for the synthesis of n-butyl naphthyl ether is presented. This procedure represents an easy method for the production of an aryl ether by an SN2 reaction, uses ethanol as an environmentally friendly solvent, and does not require the use of a lachrymator. Product isolation is done by pouring the reaction mixture over ice and collecting the solid by suction filtration. Students typically recover from 7–95% of the ether.

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Management And Social Indicators Of Soil Carbon Storage In A Residential Ecosystem, Midlothian, Va, Christopher M. Gough, Eliza A. Fritz Jan 2009

Management And Social Indicators Of Soil Carbon Storage In A Residential Ecosystem, Midlothian, Va, Christopher M. Gough, Eliza A. Fritz

Virginia Journal of Science

Soil carbon storage- defined here as carbon mass per unit ground area- is an important ecosystem service, sequestering carbon that might otherwise exist in atmospheric CO2 . Significant attention has focused on the effects that humans have on carbon cycling, but little is known about how human behaviors and attitudes relate to lawn carbon storage. The objectives of this study were to conduct household surveys in concert with soil carbon sampling in a 10-year-old exurban neighborhood near Richmond, Virginia to quantify differences in soil carbon storage between residential lawns and mixed pine-hardwood forest fragments, and to determine how lawn …

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Room Maps & Benchmark Problems, Nathan R. Sturtevant Jan 2009

Room Maps & Benchmark Problems, Nathan R. Sturtevant

Moving AI Lab: 2D Maps and Benchmark Problems

Contains 40 maps of size 512x512 and problem sets. Maps are divided into rooms of size 8x8, 16x16, 32x32, and 64x64. There are 10 maps and problem sets for each room size. Maps with differing room sizes are not scaled: thickness of walls and passages differs.

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Maze Maps & Benchmark Problems, Nathan R. Sturtevant Jan 2009

Maze Maps & Benchmark Problems, Nathan R. Sturtevant

Moving AI Lab: 2D Maps and Benchmark Problems

Contains 60 maps of size 512x512 and benchmark problem sets. These maps are algorithm-generated mazes with corridor widths of 1, 2, 4, 8, 16, or 32. There are 10 maps and problem sets for each corridor size.

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A Greedy Algorithm For Unimodal Kernel Density Estimation By Data Sharpening, Mark A. Wolters Jan 2009

A Greedy Algorithm For Unimodal Kernel Density Estimation By Data Sharpening, Mark A. Wolters

Statistical and Actuarial Sciences Publications

Nonparametric methods for smoothing, regression, and density estimation produce estimators with great shape flexibility. Although this flexibility is an advantage, the practical value of nonparametric methods would be increased if qualitative constraints—natural-language shape restrictions—could also be imposed on the estimator. In density estimation, the most common such constraints are monotonicity (the density must be nondecreasing or nonincreasing) and unimodality (the density must have only one peak). The work presented here takes unimodal kernel density estimation as a representative problem in constrained nonparametric estimation. The method proposed for handling the constraint is data sharpening. A greedy algorithm is described for achieving …

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The Effect Of Vegetated Roofs On Acid Precipitation Runoff, Jennifer Gillen Jan 2009

The Effect Of Vegetated Roofs On Acid Precipitation Runoff, Jennifer Gillen

Geology Theses and Dissertations

Vegetated, or “green” roofs are used in urban architecture and sustainable building to capture stormwater and enhance urban wildlife. Most research to date has focused on their water retention capabilities, but green roofs also have the potential to treat anthropogenic acid precipitation in urban environments. More specifically, green roofs could reduce sulfate, nitrate and hydrogen ion concentrations in runoff. One previous study has demonstrated that nitrate was reduced in water draining from a green roof (Berndtsson, et al. 2006), but this unpublished thesis appears to be the first comprehensive study of the effects of vegetated roof materials on major ions …

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Metal Concentrations In Native Yupik Foodstuffs From St. Lawrence Island, Alaska, Judith Kricheff Jan 2009

Metal Concentrations In Native Yupik Foodstuffs From St. Lawrence Island, Alaska, Judith Kricheff

Geology Theses and Dissertations

The Yupik people of St. Lawrence Island, Alaska have a traditional subsistence lifestyle with the majority of their diet consisting of local birds, fish, seal, walrus, and whale. Diets based on fish and marine mammals, such as the Yupik diet, are potential pathways for exposure to mercury and other toxic metals. At St. Lawrence Island, metal contaminants may come from local sources such as weathered rock or two abandoned U.S. military bases or remote sources through atmospheric deposition or seasonal migration of animals to the island.
The main goals of this study are to determine the total concentrations of copper …

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Mercury Uptake By Aquatic Macrophytes In Urban And Rural Watersheds, Albany County, Ny, Bernd G. Neumann Jan 2009

Mercury Uptake By Aquatic Macrophytes In Urban And Rural Watersheds, Albany County, Ny, Bernd G. Neumann

Geology Theses and Dissertations

Plants growing in metalliferous soils may restrict metal uptake and transport depending on metal concentration, sediment characteristics, and plant species. As native plants are replaced by invasives, different patterns of metal cycling can occur, making continued study of this process important. Sediments and tissues of four aquatic plant species/genera: Phragmites australis (common reed); Iris versicolor (blueflag iris); Typha latifolia (broadleaf cattail); and genera Cyperus sp. (sedge) from three urban and two rural sites in Albany County, NY were analyzed for total mercury (Hg­T) by cold vapor atomic absorption spectroscopy. Sediments were also measured for organic carbon (OC) by …

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Destination Green, Mary Ellen Mallia Jan 2009

Destination Green, Mary Ellen Mallia

Presentations

Presented at the Northeast Campus Sustainability Consortium Conference

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Creating A Carbon Neutral Campus: The University At Albany’S Climate Action Report, Mary Ellen Mallia, Indumathi, Tina Daniels Jan 2009

Creating A Carbon Neutral Campus: The University At Albany’S Climate Action Report, Mary Ellen Mallia, Indumathi, Tina Daniels

Carbon Neutral Plans

This report provides a plan for reducing green house gas emissions.

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Photodissolution And Other Photochemical Changes Upon Irradiation Of Algal Detritus, Lawrence L. Mayer, Linda L. Schick, Kathleen R. Hardy, Meg Estapa Jan 2009

Photodissolution And Other Photochemical Changes Upon Irradiation Of Algal Detritus, Lawrence L. Mayer, Linda L. Schick, Kathleen R. Hardy, Meg Estapa

Geosciences

Several recent lines of literature point toward strong photoreactivity of phytoplanktonic detritus. We examined effects of irradiation of algal membrane fragments in various stages of decay, with emphasis on transfer of materials from solid to dissolved phase (photodissolution). After simulated solar irradiation for 24 h, up to several tens of percent of particulate organic matter converted to photodissolved organic matter (PDOM). Prior microbial decay enhanced PDOM production. PDOM had initially high C:N ratios, which decreased with irradiation time. Dissolved organic nitrogen dominated nitrogen photodissolution, followed by minor photoammonification and negligible nitrite plus nitrate production. Chromophoric particulate organic matter bleached at …

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Discrete Mathematics With Proof Second Edition, Eric Gossett Jan 2009

Discrete Mathematics With Proof Second Edition, Eric Gossett

Faculty Books

Discrete mathematics has become increasingly popular in recent years due to its growing applications in the field of computer science. Discrete Mathematics with Proof, Second Edition continues to facilitate an up-to-date understanding of this important topic, exposing readers to a wide range of modern and technological applications. The book begins with an introductory chapter that provides an accessible explanation of discrete mathematics. Subsequent chapters explore additional related topics including counting, finite probability theory, recursion, formal models in computer science, graph theory, trees, the concepts of functions, and relations.

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Critical Infrastructure Protection Status And Action Items Of Turkey, Bilge Karabacak, Sevgi Ozkan Jan 2009

Critical Infrastructure Protection Status And Action Items Of Turkey, Bilge Karabacak, Sevgi Ozkan

All Faculty and Staff Scholarship

Critical infrastructures are the physical and virtual systems essential to the minimum operations of the economy and the government. Critical Infrastructure Protection (CIP) is a critical agenda item for governments in the developed countries. In these countries, policies and procedures on CIP are already in place and required laws are in action as well. In Turkey, some official introductory studies have been performed in 2009. However, there are a number of steps that Turkey still has to take. In this study, key definitions are provided firstly. After the definitions, the efforts of USA, EU, OECD and NATO are summarized. The …

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Absolute Magnitude Distribution And Light Curves Of Gamma-Ray Burst Supernovae., D. Richardson Jan 2009

Absolute Magnitude Distribution And Light Curves Of Gamma-Ray Burst Supernovae., D. Richardson

Faculty and Staff Publications

Photometry data were collected from the literature and analyzed for supernovae (SNe) that are thought to have a gamma-ray burst (GRB) association. There are several GRBs afterglow light curves that appear to have an SN component. For these light curves, the SN component was extracted and analyzed. An SN light-curve model was used to help determine the peak absolute magnitudes as well as estimates for the kinetic energy, ejected mass, and nickel mass in the explosion. The peak absolute magnitudes are, on average, brighter than those of similar SNe (stripped-envelope SNe) that do not have a GRB association, but this …

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Impact Of Tablet Pcs And Dyknow Software On Learning Gains In Inquiry-Learning Oriented Courses, Zdeslav Hrepic Jan 2009

Impact Of Tablet Pcs And Dyknow Software On Learning Gains In Inquiry-Learning Oriented Courses, Zdeslav Hrepic

Faculty Bibliography

Tablet PCs and DyKnow software were utilized at Fort Hays State University in the teaching of an inquiry-based physical science course for elementary education majors since the summer semester of 2006. This course was originally developed in 2004 and 2005 through an NSF sponsored research effort. In this paper we compare learning gains obtained in this course during three semesters when pen-based computing technology was not utilized (Fall 04 - Fall 05) with gains obtained during three later semesters (Fall 07 - Fall 08) in which we utilized Tablet PCs and DyKnow software in teaching the course. We also report …

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