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2006

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Articles 4171 - 4200 of 5872

Full-Text Articles in Physical Sciences and Mathematics

Continued Disappearance Of The Benthic Amphipod Diporeia Spp. In Lake Michigan: Is There Evidence For Food Limitation?, Thomas F. Nalepa, David L. Fanslow, Andrew J. Foley Iii, Gregory A. Lang, Brian J. Eadie, Michael A. Quigley Jan 2006

Continued Disappearance Of The Benthic Amphipod Diporeia Spp. In Lake Michigan: Is There Evidence For Food Limitation?, Thomas F. Nalepa, David L. Fanslow, Andrew J. Foley Iii, Gregory A. Lang, Brian J. Eadie, Michael A. Quigley

United States Department of Commerce: Staff Publications

Benthic surveys were conducted in the southern basin of Lake Michigan and throughout the lake to assess trends in benthic populations, emphasizing recent changes in densities of the benthic amphipod Diporeia spp. and dreissenid mussels. In the southern basin, Diporeia populations declined 89%, 91%, and 45% between 1993 and 2002 at sites <30, 31–50, and 51–90 m, respectively. Lakewide, the population declined 65% between 1994–1995 and 2000. Over the same time period, dreissenid densities, particularly Dreissena bugensis, increased. Intensive studies at 45 m sites in the southeastern region examined changes in lipid content, age structure, and benthic food inputs relative to the hypothesis that food limitation was a factor in Diporeia’s disappearance. As Diporeia densities declined to zero, length–weight remained unchanged, …

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A Minimum-Impact Method For Measuring Corrosion Rate Of Steel-Hulled Shipwrecks In Seawater, Matthew A. Russell, David L. Conlin, Larry E. Murphy, Donald L. Johnson, Brent M. Wilson, James D. Carr Jan 2006

A Minimum-Impact Method For Measuring Corrosion Rate Of Steel-Hulled Shipwrecks In Seawater, Matthew A. Russell, David L. Conlin, Larry E. Murphy, Donald L. Johnson, Brent M. Wilson, James D. Carr

Chemistry Department: Faculty Publications

Current research on USS Arizona is focused on a minimum-impact technique for calculating corrosion rate of the battleship’s steel hull by analysing physical and chemical properties of marine encrustation covering the exposed hull. An equation is derived that allows concretion thickness, density, and total iron content to be used to calculate corrosion rate of steel hull plate.

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Multi-Species Patterns Of Avian Cholera Mortality In Nebraska’S Rainwater Basin, Julie A. Blanchong, Michael D. Samuel, Gene Mack Jan 2006

Multi-Species Patterns Of Avian Cholera Mortality In Nebraska’S Rainwater Basin, Julie A. Blanchong, Michael D. Samuel, Gene Mack

United States Geological Survey: Staff Publications

Nebraska’s Rainwater Basin (RWB) is a key spring migration area for millions of waterfowl and other avian species. Avian cholera has been endemic in the RWB since the 1970s and in some years tens of thousands of waterfowl have died from the disease. We evaluated patterns of avian cholera mortality in waterfowl species using the RWB during the last quarter of the 20th century. Mortality patterns changed between the years before (1976–1988) and coincident with (1989–1999) the dramatic increases in lesser snow goose abundance and mortality. Lesser snow geese (Chen caerulescens caerulescens) have commonly been associated with mortality …

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A Cool Eastern Pacific Ocean At The Close Of The Last Interglacial Complex, Daniel R. Muhs, Kathleen R. Simmons, George L. Kennedy, Kenneth R. Ludwig, Lindsey T. Groves Jan 2006

A Cool Eastern Pacific Ocean At The Close Of The Last Interglacial Complex, Daniel R. Muhs, Kathleen R. Simmons, George L. Kennedy, Kenneth R. Ludwig, Lindsey T. Groves

United States Geological Survey: Staff Publications

New high-precision thermal ionization mass-spectrometric (TIMS) U-series ages of solitary corals (Balanophyllia elegans) from several marine terrace localities along the California and southern Oregon coasts date to the ~80,000 yr BP high stand of sea, correlative with marine isotope substage 5a, late in the last interglacial complex. Ages of multiple corals from localities north of Point Año Nuevo (central California) and San Nicolas Island (southern California) suggest that this high sea stand could have lasted at least 8000 yr, from ~84,000 to ~76,000 yr BP. These ages overlap with those from marine deposits on tectonically stable Bermuda and …

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Paleoclimatic Evidence For Future Ice-Sheet Instability And Rapid Sea-Level Rise, Jonathan T. Overpeck, Bette L. Otto-Bliesner, Gifford H. Miller, Daniel R. Muhs, Richard B. Alley, Jeffrey T. Kiehl Jan 2006

Paleoclimatic Evidence For Future Ice-Sheet Instability And Rapid Sea-Level Rise, Jonathan T. Overpeck, Bette L. Otto-Bliesner, Gifford H. Miller, Daniel R. Muhs, Richard B. Alley, Jeffrey T. Kiehl

United States Geological Survey: Staff Publications

Sea-level rise from melting of polar ice sheets is one of the largest potential threats of future climate change. Polar warming by the year 2100 may reach levels similar to those of 130,000 to 127,000 years ago that were associated with sea levels several meters above modern levels; both the Greenland Ice Sheet and portions of the Antarctic Ice Sheet may be vulnerable. The record of past ice-sheet melting indicates that the rate of future melting and related sea-level rise could be faster than widely thought.

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Ice Sheets And Sea Level, Johannes Oerlemans, Dorthe Dahl-Jensen, Valérie Masson-Delmotte, Jonathan T. Overpeck, Bette L. Otto-Bliesner, Gifford H. Miller, Richard B. Alley, Daniel R. Muhs, Shawn J. Marshall Jan 2006

Ice Sheets And Sea Level, Johannes Oerlemans, Dorthe Dahl-Jensen, Valérie Masson-Delmotte, Jonathan T. Overpeck, Bette L. Otto-Bliesner, Gifford H. Miller, Richard B. Alley, Daniel R. Muhs, Shawn J. Marshall

United States Geological Survey: Staff Publications

The estimate of the contribution of the Greenland Ice Sheet (GIS) to the higher sea level stand in the Eemian interglacial (between 2.2 and 3.4 m) is based on the assumption that there was no ice at the location of the Dye-3 ice core in southern Greenland. However, Eemian ice has been found at the base of this ice core. The presence of Eemian ice in south and coastal Greenland implies that the GIS was essentially intact in a much warmer climate and could not have contributed more than 1 to 2 m to sea-level rise.

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Acoustic Stratigraphy Of Bear Lake, Utah–Idaho—Late Quaternary Sedimentation Patterns In A Simple Half-Graben, Steven M. Colman Jan 2006

Acoustic Stratigraphy Of Bear Lake, Utah–Idaho—Late Quaternary Sedimentation Patterns In A Simple Half-Graben, Steven M. Colman

United States Geological Survey: Staff Publications

A277-km network of high-resolution seismic-reflection profiles, supplemented with a sidescan-sonar mosaic of the lake floor, was collected in Bear Lake, Utah–Idaho, in order to explore the sedimentary framework of the lake’s paleoclimate record. The acoustic stratigraphy is tied to a 120 m deep, continuously cored drill hole in the lake. Based on the age model for the drill core, the oldest continuously mapped acoustic reflector in the data set has an age of about 100 ka, although older sediments were locally imaged.

The acoustic stratigraphy of the sediments below the lake indicates that the basin developed primarily as a simple …

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The Geochemical Record Of The Last 17,000 Years In The Guaymas Basin, Gulf Of California, Walter E. Dean Jan 2006

The Geochemical Record Of The Last 17,000 Years In The Guaymas Basin, Gulf Of California, Walter E. Dean

United States Geological Survey: Staff Publications

Sediments deposited on the western slope of the Guaymas Basin in the central Gulf of California are composed predominantly of detrital clastic material and biogenic silica (biopal), with minor organic material (average of 2.8% organic carbon) and calcium carbonate. The CaCO3 is derived from calcareous plankton and is highly variable ranging from 0% to 16%. In general, the CaCO3 content of the sediments varies inversely with the biopal content, reflecting the relative abundance of calcareous and siliceous plankton in the photic zone. Siliceous plankton dominate when winds are predominantly out of the northwest producing strong upwelling. Calcareous plankton …

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Abundance And Distribution Of Selected Elements In Soils, Stream Sediments, And Selected Forage Plants From Desert Tortoise Habitats In The Mojave And Colorado Deserts, Usa, M. A. Chaffee, K. H. Berry Jan 2006

Abundance And Distribution Of Selected Elements In Soils, Stream Sediments, And Selected Forage Plants From Desert Tortoise Habitats In The Mojave And Colorado Deserts, Usa, M. A. Chaffee, K. H. Berry

United States Geological Survey: Staff Publications

A baseline and background chemical survey was conducted in southeastern California, USA, to identify potential sources of toxicants in natural and anthropogenically-altered habitats of the threatened desert tortoise (Gopherus agassizii). Soil, stream sediment, and plant samples were collected from six tortoise habitat study areas in the Mojave and Colorado deserts and analysed for up to 66 different elements. The chemical analyses provided new information on the abundances and distributions of selected elements in this region. Soil, stream-sediment, and plant analyses showed distinct variations in bulk chemistries from locality to locality. Variations were, in general, consistent with the many …

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Mineralogical Characterization Of Protolith And Fault Rocks From The Safod Main Hole, John G. Solum, Stephen H. Hickman, David A. Lockner, Diane E. Moore, Ben A. Van Der Pluijm, James P. Evans Jan 2006

Mineralogical Characterization Of Protolith And Fault Rocks From The Safod Main Hole, John G. Solum, Stephen H. Hickman, David A. Lockner, Diane E. Moore, Ben A. Van Der Pluijm, James P. Evans

United States Geological Survey: Staff Publications

Washed cuttings provide a continuous record of the rocks encountered during drilling of the main hole of the San Andreas Fault Observatory at Depth (SAFOD). Both protolith and fault rocks exhibit a wide variety of mineral assemblages that reflect variations in some combination of lithology, P-T conditions, deformation mechanisms, and fluid composition and abundance. Regions of distinct neomineralization bounded by faults may record alteration associated with fluid reservoirs confined by faults. In addition, both smectites occurring as mixed-layer phases and serpentine minerals are found in association with active strands of the San Andreas Fault that were intersected during drilling, although …

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Measuring Groundwater–Surface Water Interaction And Its Effect On Wetland Stream Benthic Productivity, Trout Lake Watershed, Northern Wisconsin, Usa, Randall J. Hunt, Mac Strand, John F. Walker Jan 2006

Measuring Groundwater–Surface Water Interaction And Its Effect On Wetland Stream Benthic Productivity, Trout Lake Watershed, Northern Wisconsin, Usa, Randall J. Hunt, Mac Strand, John F. Walker

United States Geological Survey: Staff Publications

Measurements of groundwater–surface water exchange at three wetland stream sites were related to patterns in benthic productivity as part of the US Geological Survey’s Northern Temperate Lakes–Water, Energy and Biogeochemical Budgets (NTL–WEBB) project. The three sites included one high groundwater discharge (HGD) site, one weak groundwater discharge (WGD) site, and one groundwater recharge (GR) site. Large upward vertical gradients at the HGD site were associated with smallest variation in head below the stream and fewest gradient reversals between the stream and the groundwater beneath the stream, and the stream and the adjacent streambank. The WGD site had the highest number …

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Endangered Species Time Line, Leona K. Svancara, J. Michael Scott, Dale D. Goble, Frank W. Davis, Donna Brewer Jan 2006

Endangered Species Time Line, Leona K. Svancara, J. Michael Scott, Dale D. Goble, Frank W. Davis, Donna Brewer

United States Geological Survey: Staff Publications

The Endangered Species Act (ESA) is embedded in a web of statutes designed to regulate relationships between humans and other species that stretch back nearly a millennium (Goble, this volume; Goble and Freyfogle 2002). This chapter presents a time line of federal actions taken to protect wildlife beginning with passage of the Land and Water Conservation Fund Act in 1963 (Act of May 28, 1963). Earlier laws to protect wildlife are discussed elsewhere (Goble, this volume). The time line emphasizes federal actions that conserve species at risk of extinction and significant events in the course of implementing the Endangered Species …

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Sulfur Isotope Geochemistry Of Sulfide Minerals, Robert R. Seal Ii Jan 2006

Sulfur Isotope Geochemistry Of Sulfide Minerals, Robert R. Seal Ii

United States Geological Survey: Staff Publications

Sulfur, the 10th most abundant element in the universe and the 14th most abundant element in the Earth’s crust, is the defining element of sulfide minerals and provides insights into the origins of these minerals through its stable isotopes. The insights come from variations in the isotopic composition of sulfide minerals and related compounds such as sulfate minerals or aqueous sulfur species, caused by preferential partitioning of isotopes among sulfur-bearing phases, known as fractionation. These variations arise from differences in temperature, or more importantly, oxidation and reduction reactions acting upon the sulfur. The oxidation and reduction reactions can occur at …

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Simulation Of Solute Movement Through Wellbores To Characterize Public Supply Well Contaminant Vulnerability In The High Plains Aquifer, York, Nebraska, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Z. Hornberger Jan 2006

Simulation Of Solute Movement Through Wellbores To Characterize Public Supply Well Contaminant Vulnerability In The High Plains Aquifer, York, Nebraska, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Z. Hornberger

United States Geological Survey: Staff Publications

A ground-water flow and transport model simulating contaminant movement to public supply wells in the High Plains aquifer near York, Nebraska was developed as part of the U.S. Geological Survey National Water-Quality Assessment Program. Water-quality samples were collected from wells screened in unconfined and confined units. Samples collected from a public supply well and selected monitoring wells completed in the confined aquifer have chemistry and age-tracer concentrations consistent with a mix of young water from unconfined recharge areas combined with relatively older confined aquifer water. These results imply that there are preferential flow paths that permit shallow recharge water and …

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Regional Patterns In The Isotopic Composition Of Natural And Anthropogenic Nitrate In Groundwater, High Plains, U.S.A., P. B. Mcmahon, J. K. Bohlke Jan 2006

Regional Patterns In The Isotopic Composition Of Natural And Anthropogenic Nitrate In Groundwater, High Plains, U.S.A., P. B. Mcmahon, J. K. Bohlke

United States Geological Survey: Staff Publications

Mobilization of natural nitrate (NO3-) deposits in the subsoil by irrigation water in arid and semiarid regions has the potential to produce large groundwater NO3- concentrations. The use of isotopes to distinguish between natural and anthropogenic NO3- sources in these settings could be complicated by the wide range in δ15N values of natural NO3-. An ~10 000 year record of paleore-charge from the regionally extensive High Plains aquifer indicates that δ15N values for NO3- derived from natural sources ranged from 1.3 to 12.3‰ and …

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Spring Census Of Mid-Continent Sandhill Cranes Using Aerial Infrared Videography, Paul Kinzel, Jonathan Nelson, Randolph Parker, Lawrence Davis Jan 2006

Spring Census Of Mid-Continent Sandhill Cranes Using Aerial Infrared Videography, Paul Kinzel, Jonathan Nelson, Randolph Parker, Lawrence Davis

United States Geological Survey: Staff Publications

Aerial infrared videography was used to map spatial distributions of nocturnal sandhill crane (Grus canadensis) flocks and determine crane densities within roosts as an alternative to the currently used diurnal photo-corrected ocular transect method to estimate the size of the midcontinental population. The densities determined from samples taken over the course of a night show variability. Densities measured early in the night (2100 to 2300 hrs) were generally lower than those measured in the time period after midnight and up until cranes prepared to depart their roosts before sunrise. This suggests that cranes may be more active early …

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Gastrointestinal Morphology Of Female White-Tailed And Mule Deer: Effects Of Fire, Reproduction, And Feeding Type, Teresa J. Zimmerman, Jonathan A. Jenks, David M. Leslie Jr. Jan 2006

Gastrointestinal Morphology Of Female White-Tailed And Mule Deer: Effects Of Fire, Reproduction, And Feeding Type, Teresa J. Zimmerman, Jonathan A. Jenks, David M. Leslie Jr.

United States Geological Survey: Staff Publications

We assessed variation in length, width, density, and surface enlargement factor of papillae; rumen and intestinal digesta weight; intestinal length; and intestinal tissue weight of reproductive and nonreproductive female white-tailed (Odocoileus virginianus) and mule deer (O. hemionus) using similar burned and unburned habitat. Deer were collected from study areas in Custer and Pennington counties, South Dakota, in and adjacent to a wildfire burn. Length of papillae and enlargement factor of papillae surface of white-tailed deer and mule deer were greater in burned than unburned habitat, and dry weight of rumen digesta of white-tailed deer was greater …

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A Quantitative Method For Iso 17799 Gap Analysis, Bilge Karabacak, Ibrahim Sogukpinar Jan 2006

A Quantitative Method For Iso 17799 Gap Analysis, Bilge Karabacak, Ibrahim Sogukpinar

All Faculty and Staff Scholarship

ISO/IEC 17799:2005 is one of the leading standards of information security. It is the code of practice including 133 controls in 11 different domains. There are a number of tools and software that are used by organizations to check whether they comply with this standard. The task of checking compliance helps organizations to determine their conformity to the controls listed in the standard and deliver useful outputs to the certification process. In this paper, a quantitative survey method is proposed for evaluating ISO 17799 compliance. Our case study has shown that the survey method gives accurate compliance results in a …

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Plasma Treatment Of Bulk Niobium Surfaces For Srf Cavities, M. Rašković, L. Vuškovic, S. Popović, L. Phillips, A. -M. Valente-Feliciano, S. B. Radovanov, L. Godet Jan 2006

Plasma Treatment Of Bulk Niobium Surfaces For Srf Cavities, M. Rašković, L. Vuškovic, S. Popović, L. Phillips, A. -M. Valente-Feliciano, S. B. Radovanov, L. Godet

Physics Faculty Publications

Two types of electric discharges were used to demonstrate the validity of plasma surface treatment for superconducting radio-frequency (SRF) cavities. The experiments were performed on disc-shaped Nb samples and compared with identical samples treated with buffer chemical polishing (BCP) techniques. Surface analysis indicates comparable or superior properties of plasma-treated samples. These promising results are still preliminary and additional work is in progress.

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Differential Cross Sections For 𝛾 + P → K⁺ + Y For Λ And Σ⁰ Hyperons, H. Bagdasaryan, M. Bektasoglu, S. L. Careccia, S. Bültmann, G. E. Dodge, N. Guler, C. E. Hyde-Wright, H. G. Juengst, A. V. Klimenko, S. E. Kuhn, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., Clas Collaboration Jan 2006

Differential Cross Sections For 𝛾 + P → K⁺ + Y For Λ And Σ⁰ Hyperons, H. Bagdasaryan, M. Bektasoglu, S. L. Careccia, S. Bültmann, G. E. Dodge, N. Guler, C. E. Hyde-Wright, H. G. Juengst, A. V. Klimenko, S. E. Kuhn, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., Clas Collaboration

Physics Faculty Publications

High-statistics cross sections for the reactions 𝛾 + p → K⁺ + Λ and 𝛾 + p → K⁺ + Σ⁰ have been measured using CLAS at Jefferson Lab for center-of-mass energies W between 1.6 and 2.53 GeV, and for -0.85 < cos θ Kc.m. < +0.95. In the K⁺ + Λ channel we confirm a resonance-like structure near W=1.9 GeV at backward kaon angles. The position and width of this structure change with angle, indicating that more than one resonance is likely playing a role. The K⁺ + Λ channel at forward angles and all energies is well described by a t-channel scaling characteristic of Regge exchange, whereas the same scaling applied to the K⁺ + Σ⁰ channel is less successful. Several existing theoretical models are compared to the data, but none provide a good representation of the results.

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Development Of The Maryland Shoreline Inventory Methods And Guidelines For Calvert County - Gis Data, Marcia Berman, Harry Berquist, Sharon Killeen, Karen Reay, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, David Weiss Jan 2006

Development Of The Maryland Shoreline Inventory Methods And Guidelines For Calvert County - Gis Data, Marcia Berman, Harry Berquist, Sharon Killeen, Karen Reay, Karinna Nunez, Tamia Rudnicky, Daniel E. Schatt, David Weiss

Data

The Center for Coastal Resources Management (CCRM) at the Virginia Institute of Marine Science (VIMS) has generated Shoreline Situation Reports (SSRs) for coastal localities in the state of Maryland. This effort compliments a parallel effort in Virginia by the same group. SSRs were developed by VIMS in the 1970s for Virginia and have been the foundation for shoreline management planning in Tidewater Virginia ever since. CCRM has developed new protocols for collecting, disseminating, and reporting data relevant to shoreline management issues using state of the art mapping and remote sensing techniques. New SSRs are being generated on a county by …

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A Novel Minimized Dead-End Elimination Criterion And Its Application To Protein Redesign In A Hybrid Scoring And Search Algorithm For Computing Partition Functions Over Molecular Ensembles, Ivelin Georgiev, Ryan H. Lilien, Bruce R. Donald Jan 2006

A Novel Minimized Dead-End Elimination Criterion And Its Application To Protein Redesign In A Hybrid Scoring And Search Algorithm For Computing Partition Functions Over Molecular Ensembles, Ivelin Georgiev, Ryan H. Lilien, Bruce R. Donald

Computer Science Technical Reports

Novel molecular function can be achieved by redesigning an enzyme's active site so that it will perform its chemical reaction on a novel substrate. One of the main challenges for protein redesign is the efficient evaluation of a combinatorial number of candidate structures. The modeling of protein flexibility, typically by using a rotamer library of commonly-observed low-energy side-chain conformations, further increases the complexity of the redesign problem. A dominant algorithm for protein redesign is Dead-End Elimination (DEE), which prunes the majority of candidate conformations by eliminating rigid rotamers that provably are not part of the Global Minimum Energy Conformation (GMEC). …

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Use Of Gene Expression Profiling And Machine Learning To Understand And Predict Primary Graft Dysfunction, Monika Ray, Sekhar Dharmarajan, Johannes Freudenberg, Weixiong Zhang, Alexander G. Patterson Jan 2006

Use Of Gene Expression Profiling And Machine Learning To Understand And Predict Primary Graft Dysfunction, Monika Ray, Sekhar Dharmarajan, Johannes Freudenberg, Weixiong Zhang, Alexander G. Patterson

All Computer Science and Engineering Research

No abstract provided.

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Design Of Routers For Diversified Networks, Jonathan Turner Jan 2006

Design Of Routers For Diversified Networks, Jonathan Turner

All Computer Science and Engineering Research

No abstract provided.

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The Real Effect Of Warm-Cool Colors, Reynold J. Bailey, Cindy M, Grimm, Chris Davoli Jan 2006

The Real Effect Of Warm-Cool Colors, Reynold J. Bailey, Cindy M, Grimm, Chris Davoli

All Computer Science and Engineering Research

The phenomenon of warmer colors appearing nearer in depth to viewers than cooler colors has been studied extensively by psychologists and other vision researchers. The vast majority of these studies have asked human observers to view physically equidistant, colored stimuli and compare them for relative depth. However, in most cases, the stimuli presented were rather simple: straight colored lines, uniform color patches, point light sources, or symmetrical objects with uniform shading. Additionally, the colors used were typically highly saturated. Although such stimuli are useful in isolating and studying depth cues in certain contexts, they leave open the question of whether …

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Perceptually Meaningful Image Editing: Depth, Reynold J. Bailey, Cindy Grimm Jan 2006

Perceptually Meaningful Image Editing: Depth, Reynold J. Bailey, Cindy Grimm

All Computer Science and Engineering Research

We introduce the concept of perceptually meaningful image editing and present two techniques for manipulating the apparent depth of objects in an image. The user loads an image, selects an object and specifies whether the object should appear closer or further away. The system automatically determines target values for the object and/or background that achieve the desired depth change. These depth editing operations, based on techniques used by traditional artists, manipulate either the luminance or color temperature of different regions of the image. By performing blending in the gradient domain and reconstruction with a Poisson solver, the appearance of false …

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Fast Packet Classification Using Bloom Filters, Sarang Dharmapurikar, Haoyu Song, Jonathan Turner, John Lockwood Jan 2006

Fast Packet Classification Using Bloom Filters, Sarang Dharmapurikar, Haoyu Song, Jonathan Turner, John Lockwood

All Computer Science and Engineering Research

While the problem of general packet classification has received a great deal of attention from researchers over the last ten years, there is still no really satisfactory solution. Ternary Content Addressable Memory (TCAM), although widely used in practice, is both expensive and consumes a lot of power. Algorithmic solutions, which rely on commodity memory chips, are relatively inexpensive and power-efficient, but have not been able to match the generality and performance of TCAMs. In this paper we propose a new approach to packet classification, which combines architectural and algorithmic techniques. Our starting point is the well-known crossproducting algorithm, which is …

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Smooth Key-Framing Using The Image Plane, Leon Barrett, Cindy Grimm Jan 2006

Smooth Key-Framing Using The Image Plane, Leon Barrett, Cindy Grimm

All Computer Science and Engineering Research

This paper demonstrates the use of image-space constraints for key frame interpolation. Interpolating in image-space results in sequences with predictable and controlable image trajectories and projected size for selected objects, particularly in cases where the desired center of rotation is not fixed or when the key frames contain perspective distortion changes. Additionally, we provide the user with direct image-space control over {\em how} the key frames are interpolated by allowing them to directly edit the object's projected size and trajectory. Image-space key frame interpolation requires solving the inverse camera problem over a sequence of point constraints. This is a variation …

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Limit Crossing For Decision Problems, Sharlee Climer, Weixiong Zhang Jan 2006

Limit Crossing For Decision Problems, Sharlee Climer, Weixiong Zhang

All Computer Science and Engineering Research

Limit crossing is a methodology in which modified versions of a problem are solved and compared, yielding useful information about the original problem. Pruning rules that are used to exclude portions of search trees are excellent examples of the limit-crossing technique. In our previous work, we examined limit crossing for optimization problems. In this paper, we extend this methodology to decision problems. We demonstrate the use of limit crossing in our design of a tool for identifying K-SAT backbones. This tool is guaranteed to identify all of the backbone variables by solving at most n+1 formulae, where n is the …

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Design Of A Diversified Network Substrate, Jonathan Turner Jan 2006

Design Of A Diversified Network Substrate, Jonathan Turner

All Computer Science and Engineering Research

A diversified network substrate enables multiple end-to-end metanetworks to co-exist within a shared physical infrastructure. Metanetworks are implemented by metarouters, hosted by substrate routers, and metarouters are connected by metalinks. The substrate allocates resources (both link bandwidth and processing resources) to metarouters based on advance reservations received from metanetwork planning systems. It also enables dynamic creation of access metalinks, connecting end systems to metarouters, and supports mobility of end systems under the control of their metanetworks. This report defines a model for a diversified internet and presents a detailed design of the substrate that enables metanetworks to co-exist. The design …

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