Development and Performance Evaluation of a Real-Time Web Search Engine

As the World Wide Web continues to grow, the tools to retrieve the information must develop in terms of locating web pages, categorizing content, and retrieving quality pages. Web search engines have enhanced the online experience by making pages easier to find. Search engines have made a science of cataloging page content, but the data can age, becoming outdated and irrelevant. By searching pages in real time in a localized area of the web, information that is retrieved is guaranteed to be available at the time of the search. The real-time search engines intriguing premise provides an overwhelming challenge. Since the web is searched in real time, the engine\u27s execution will take longer than traditional search engines. The challenge is to determine what factors can enhance the performance of the real-time search engine. This research takes a look at three components: traversal methodologies for searching the web, utilizing concurrently executing spiders, and implementing a caching resource to reduce the execution time of the real-time search engine. These components represent some basic methodologies to improve performance. By determining which implementations provide the best response, a better and faster real-time search engine can become a useful searching tool for Internet users

Reconstruction of eolian bed forms and paleocurrents from cross-bedded strata at Victoria Crater, Meridiani Planum, Mars

Outcrop exposures imaged by the Opportunity rover at Victoria Crater, a 750 m diameter crater in Meridiani Planum, are used to delineate sedimentary structures and further develop a dune-interdune depositional model for the region. The stratigraphy at Victoria Crater, observed during Opportunity's partial traverse of its rim, includes the best examples of meter-scale eolian cross bedding observed on Mars to date. The Cape St. Mary promontory, located at the southern end of the rim traverse, is characterized by meter-scale sets of trough cross bedding, suggesting northward migrating sinuous-crested bed forms. Cape St. Vincent, which is located at the opposite end of the traverse, shows tabular-planar stratification indicative of climbing bed forms with meter- to decameter-scale dune heights migrating southward. Promontories located between Cape St. Mary and Cape St. Vincent contain superposed stratigraphic units with northward and southward dipping beds separated by outcrop-scale bounding surfaces. These bounding surfaces are interpreted to be either reactivation and/or superposition surfaces in a complex erg sea. Any depositional model used to explain the bedding must conform to reversing northward and southward paleomigration directions and include multiple scales of bed forms. In addition to stratified outcrop, a bright diagenetic band is observed to overprint bedding and to lie on an equipotential parallel to the preimpact surface. Meter-scale cross bedding at Victoria Crater is similar to terrestrial eolian deposits and is interpreted as a dry dune field, comparable to Jurassic age eolian deposits in the western United States

Comptabilité et traite négrière. Le Guide du commerce de Gaignat de l'Aulnais (1718-1791)

Malgré un titre très général qui explique certainement le peu de place qui lui a été fait jusque-là dans l'histoire de la comptabilité, le Guide du commerce de Gaignat de l'Aulnais (1771) est vraisemblablement l'un des tout premiers manuels spécialisés de comptabilité, mais d'une spécialisation qui lui confère une place très particulière. Au-delà de quelques paragraphes consacrés aux matières commerciales traditionnelles — marchandises à échanger en divers pays, pratique du change, effets de commerce, poids et mesures, etc. — et d'une présentation relativement classique de la tenue des livres en partie simple et parties doubles, l'ouvrage est essentiellement consacré au commerce maritime et, plus particulièrement, à l'un de ses aspects les plus dramatiques : la traite négrière. L’essor consécutif d’une fiscalité complexe a fourni par la suite tant à ces juristes qu’aux comptables un rôle de plus en plus important qu’ils se partageaient. L’Etat, pour assurer sa quiétude quant à l’établissement de l’assiette fiscale, formalisera alors une profession comptable libérale connue aujourd’hui sous le titre d’expert-comptable.

Technology transfer from NASA to targeted industries, volume 2

This volume contains the following materials to support Volume 1: (1) Survey of Metal Fabrication Industry in Alabama; (2) Survey of Electronics Manufacturing/Assembly Industry in Alabama; (3) Apparel Modular Manufacturing Simulators; (4) Synopsis of a Stereolithography Project; (5) Transferring Modular Manufacturing Technology to an Apparel Firm; (6) Letters of Support; (7) Fact Sheets; (8) Publications; and (9) One Stop Access to NASA Technology Brochure

Using airborne LiDAR Survey to explore historic-era archaeological landscapes of Montserrat in the eastern Caribbean

This article describes what appears to be the first archaeological application of airborne LiDAR survey to historic-era landscapes in the Caribbean archipelago, on the island of Montserrat. LiDAR is proving invaluable in extending the reach of traditional pedestrian survey into less favorable areas, such as those covered by dense neotropical forest and by ashfall from the past two decades of active eruptions by the Soufrière Hills volcano, and to sites in localities that are inaccessible on account of volcanic dangers. Emphasis is placed on two aspects of the research: first, the importance of ongoing, real-time interaction between the LiDAR analyst and the archaeological team in the field; and second, the advantages of exploiting the full potential of the three-dimensional LiDAR point cloud data for purposes of the visualization of archaeological sites and features

Fluctuation Analysis of Human Electroencephalogram

The scaling behaviors of the human electroencephalogram (EEG) time series are studied using detrended fluctuation analysis. Two scaling regions are found in nearly every channel for all subjects examined. The scatter plot of the scaling exponents for all channels (up to 129) reveals the complicated structure of a subject's brain activity. Moment analyses are performed to extract the gross features of all the scaling exponents, and another universal scaling behavior is identified. A one-parameter description is found to characterize the fluctuation properties of the nonlinear behaviors of the brain dynamics.Comment: 4 pages in RevTeX + 6 figures in ep

Thermal and Dynamical Equilibrium in Two-Component Star Clusters

We present the results of Monte Carlo simulations for the dynamical evolution of star clusters containing two stellar populations with individual masses m1 and m2 > m1, and total masses M1 and M2 < M1. We use both King and Plummer model initial conditions and we perform simulations for a wide range of individual and total mass ratios, m2/m1 and M2/M1. We ignore the effects of binaries, stellar evolution, and the galactic tidal field. The simulations use N = 10^5 stars and follow the evolution of the clusters until core collapse. We find that the departure from energy equipartition in the core follows approximately the theoretical predictions of Spitzer (1969) and Lightman & Fall (1978), and we suggest a more exact condition that is based on our results. We find good agreement with previous results obtained by other methods regarding several important features of the evolution, including the pre-collapse distribution of heavier stars, the time scale on which equipartition is approached, and the extent to which core collapse is accelerated by a small subpopulation of heavier stars. We briefly discuss the possible implications of our results for the dynamical evolution of primordial black holes and neutron stars in globular clusters.Comment: 31 pages, including 13 figures, to appear in Ap

Omega-3 Fatty Acid, Selenium, and Mercury Content of Aquaculture Products in Hawaii

The purpose of this study was to gather baseline data on the fatty acid profile and selenium and mercury concentration of aquaculture products in Hawaii