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Nomenclatura Unesco > (55) Historia

Mostrando recursos 41 - 60 de 149,866

41. Privacy-preserving Digital Identity Management for Cloud Computing - Elisa Bertino; Federica Paci; Ning Shang; Rodolfo Ferrini
Digital identity management services are crucial in cloud computing infrastructures to authenticate users and to support flexible access control to services, based on user identity properties (also called attributes) and past interaction histories. Such services should preserve the privacy of users, while at the same time enhancing interoperability across multiple domains and simplifying management of identity verification. In this paper we propose an approach addressing such requirements, based on the use of high-level identity verification policies expressed in terms of identity attributes, zero-knolwedge proof protocols, and semantic matching techniques. The paper describes the basic techniques we adopt and the architeture...

42. Share Aware: An interactive Pervasive System To Promote Awareness of Workstation Ergomonics - Anurag Sehgal; Interaction Designer; Patray Wing; Lam Lui; Interaction Designer
Workstation ergonomic problems have become a major health issue in the office. Sitting in the same place for a long time and improper sitting postures while using computers can lead to a wide range of computer-related injuries. We introduce a system promoting workstation health called ’Share Aware’. ’Share Aware ’ is designed to make people aware of how to prevent computer-related injuries and help them build up correct long term computer-using habits. The interactive system consists of a seat cover with embedded sensors which track user posture and sitting time with a screen-based application that represents the data in two...

43. Modeling Human Performance from Visualization Interaction Histories
We present a novel framework called TOME that helps designers quantitatively evaluate interactive visualizations. TOME collects user-interaction histories from visualizations via an instrumentation library and can convert these histories into keystrokelevel models (KLMs) [1] that predict task-completion times using CogTool [2, 7]. Our aim is to minimize human involvement in performance-model construction, which is notoriously timeconsuming and error-prone when done manually [6]. We evaluate the framework with a brain-circuit visualization and demonstrate its use in iterative tool development.

44. La construcción mediática de Cuba. Un análisis del discurso periodístico del The Washington Post The Media’s Construction of Cuba. An Analysis of the Journalistic Discourse of The - Washington Post
Resumen: El presente artículo propone un acercamiento a los rasgos que caracterizaron la construcción del discurso periodístico del diario norteamericano The Washington Post acerca del tema Cuba, desde que se dio a conocer la proclama de Fidel Castro, el 31 de julio de 2006, hasta la elección de Raúl Castro como presidente de la Isla, en febrero de 2008. Para realizar la investigación se partió desde una perspectiva cualitativa y un tipo de diseño de caso único, inclusivo, descriptivo. El análisis crítico del discurso periodístico de The Washington Post en dos momentos significativos de la historia cubana permitió identificar los...

45. Characterization of the Monument Hill fault system and implications for the active tectonics of the Red Rock Valley, Southwestern Montana - Christine A. Regalla; David J. Anastasio; Frank J. Pazzaglia
New geologic mapping, morphologic fault scarp modeling, and geomorphic metrics in the Red Rock Valley, southwestern Montana, help characterize the Quaternary history of the virtually unstudied Monument Hill fault and tectonics of the youthful and seismically active Red Rock graben. Two generations of Pleistocene surface ruptures are preserved along the Monument Hill fault. Similarity in rupture ages along multiple strands, determined from offset alluvial surfaces and morphologic modeling, suggest earthquake clusters at 22e32 ka and possibly>160 ka. Quaternary activity along the Monument Hill fault is also reflected in elongate drainage basins and channel profiles with anomalously steep reaches coincident with...

46. A EUROPIUM, SAMARIUM, AND NEODYMIUM ISOTOPIC FRACTIONS IN METAL-POOR STARS - Ian U. Roederer; James E. Lawler; Christopher Sneden; John J. Cowan; Jennifer S. Sobeck; Catherine A. Pilachowski
We have derived isotopic fractions of europium, samarium, and neodymium in two metal-poor giants with differing neutron-capture nucleosynthetic histories. These isotopic fractions were measured from new high-resolution (R 120;000), high signal-to-noise ratio (S/N 160Y1000) spectra obtained with the 2d-coudé spectrograph of McDonald Observatory’s 2.7 m Smith telescope. Synthetic spectra were generated using recent high-precision laboratory measurements of hyperfine and isotopic subcomponents of several transitions of these elements and matched quantitatively to the observed spectra. We interpret our isotopic fractions by the nucleosynthesis predictions of the stellar model, which reproduces s-process nucleosynthesis from the physical conditions expected in low-mass, thermally pulsing...

47. $rec.titulo - Tj Morgan; Ma Evans; T Garl; Jg Swallow; Pa Carter
Molecular and quantitative genetic divergence among populations of house mice with known evolutionary histories

48. BRIEF COMMUNICATION Sex-Specific Heterosis in Line Crosses of Mice Selectively Bred for High Locomotor - Wendy Acosta; Robert C. Maciel; Heidi Schutz; R. C. Maciel; H. Schutz; T. Garl
Abstract When populations with similar histories of directional selection are crossed, their offspring may differ in mean phenotype as compared with the average for the parental populations, often exhibiting enhancement of the mean phenotype (termed heterosis or hybrid vigor). We tested for heterosis in a cross of two replicate lines of mice selectively bred for high voluntary wheel running for 53 generations. Mice were paired to produce four sets of F1 offspring: two purebred High Runner (HR) lines and the hybrid reciprocal crosses. The purebred HR showed statistically significant, sex-dependent differences in body mass, wheel revolutions, running duration, mean running...

49. ␥4 Northern Gulf of Mexico Sea-Level History for the Past 20,000 Years - James H. Balsillie; Joseph F. Donoghue
High-resolution, composite sea-level curves have been developed for the northern Gulf of Mexico for the period since the last glacial maximum. The goal of this work was twofold: (1) to define the regional sea-level history of the northern Gulf of Mexico using all of the available geochronological data on sea-level history, and (2) to examine the hypothesis that, for stable coastal regions of the Gulf of Mexico coastline, sea-level history approximates global (i.e., eustatic) sea level. The resulting sea-level curves are based on all available carbon-dated indicators of paleo-sea level and represent, on average, one measurement every 65 years for...

50. INVESTIGATING THE IMPACT OF ADVECTIVE AND DIFFUSIVE CONTROLS IN SOLUTE TRANSPORT ON GEOELECTRICAL DATA - Daniel D. Wheaton; Daniel D. Wheaton; Katherine H. Freeman
Multiple types of physical heterogeneity have been suggested to explain anomalous solute transport behavior, yet determining exactly what controls transport at a given site is difficult from concentration histories alone. Differences in timing between co-located fluid and bulk apparent electrical conductivity data have previously been used to estimate solute mass transfer rates between mobile and less mobile domains; here, we consider if this behavior can arise from other types of heterogeneity. Numerical models are used to investigate the electrical signatures associated with large-scale hydraulic conductivity heterogeneity and small-scale dualdomain mass transfer, and address issues regarding the scale of the geophysical...

51. Late-Holocene atmospheric lead deposition in the Peruvian and Bolivian Andes. The Holocene 18: 353–359 - Colin A. Cooke; Mark B. Abbott; Er P. Wolfe; Colin A. Cooke; Mark B. Abbott; Er P. Wolfe
Abstract: The analysis of lead (Pb) in lake-sediment cores is a useful method to reconstruct local histories of Pb pollution. Here, we use Pb concentration profiles from lake sediments to reconstruct local trajectories of pre-Colonial smelting from three metallurgical centres in the South American Andes: the Morococha mining district, Peru; the Bolivian Altiplano around Lake Titicaca; and the silver-mining centre of Potosí, Bolivia. The earliest evidence for Pb enrichment from smelting is on the Altiplano beginning ~AD 400, coincident with the rise of the pre-Incan Tiwanaku and Wari Empires. Coeval with the collapse of these Empires ~AD 1000, there is...

52. Sahnish Doctors: A Central Component of the Sahnish Religious System and Society University of Wisconsin-Milwaukee - Brad Kroupa; Mcnair Scholar
This research is being conducted through ethnohistory. Ethnohistory is a combination of the three other primary methodologies pertaining to studying American Indian history or culture. These methodologies include anthropology, archaeology, and history. The books, journals, and documents I have read focus on Sahnish culture, and through this I gathered information relating to doctors and their central role of Sahnish society. The process of ethnohistory also allowed me to include a contemporary voice of the people by conducting interviews to gather oral stories from the Sahnish community back home. Oral stories are crucial to this study, and to ethnohistory, because they...

53. Change Impact Analysis with Stochastic Dependencies - Sunny Wong; Yuanfang Cai; Michael Dalton
Researchers have shown that software change impact analysis (IA) can be improved by investigating logical coupling embodied in revision histories. However, prevailing historybased IA techniques do not take the temporal dimension of revision history into consideration to account for design evolution. In this paper, we formalize logical coupling as a stochastic process using a Markov chain model. By varying the length and the smoothing function of the model, we defineafamilyofstochastic dependencies. Eachmemberofthis family weights historical data differently according to their recency and frequency. To assess its utility, we conduct IA on 86 releases of five open source systems by using...

54. FrIP14.12 A Domain Decomposition Approach to POD - Christopher A. Beattie; Jeff Borggaard; Serkan Gugercin; Traian Iliescu
Abstract — The proper orthogonal decomposition (POD) is a popular approach for building reduced-order models for nonlinear distributed parameter systems. The approach is based on developing a reduced basis by post-processing one, and often multiple, high fidelity simulations of a nonlinear partial differential equation. The computational overhead required to perform just one simulation may involve the need to distribute the data and the use of parallel computing architectures. For these problems, the size of the discretization and the number of simulations may preclude ‘typical ’ POD algorithms that are based on accessing all of the information on a single processor....

55. Europium, Samarium, and Neodymium Isotopic Fractions in Metal-Poor Stars - Ian U. Roederer; James E. Lawler; Christopher Sneden; John J. Cowan; Jennifer S. Sobeck; Catherine A. Pilachowski
Abstract. We have derived isotopic fractions of europium (Eu), samarium (Sm), and neodymium (Nd) in two metal-poor giants with differing neutron-capture nucleosynthetic histories. These isotopic fractions were measured from new very high resolution {R- ^ 120,000), high signal-to-noise (S/N- ^ 160 — 1000) spectra obtained with the 2dCoude spectrograph of McDonald Observatory's 2.7 m Smith telescope. Synthetic spectra were generated using recent high-precision laboratory measurements of hyperfine and isotopic subcomponents of several transitions of these elements and matched quantitatively to the observed spectra. We interpret our isotopic fractions by the nucleosynthesis predictions of the stellar model, which models 5-process nucleosynthesis...

56. Summary - Marcelo N. Pires; Ronald D. Bassar; Kevin E. Mcbride; John U. Regus; Theodore Garl; David N. Reznick
which lack placentas and three that have placentas but vary in the extent of post-fertilization provisioning. 2. We used this diversity to evaluate a series of hypotheses proposed in earlier publications concerning why the placenta has evolved. All hypotheses share the attribute of arguing that the placenta evolved to enhance the evolution of some other life-history trait, such as to reduce the age at maturation or to increase offspring size. We refer to these hypotheses collectively as ‘life-history facilitation hypotheses’. 3. A general way to evaluate the plausibility of such proposals is to ask whether the evolution of the placenta...

57. Relationship Problems 1 Running head: MENTAL HEALTH USE AMONG SPECIAL NEEDS ADOPTIVE CHILDREN Relationship Problems and Mental Health Use Among Special Needs Adoptive Children - Thoy Bouakongxaya
Special Needs Adoptive (SNA) families comprise a subgroup of adoptive families at risk for higher levels of adjustment problems and a greater need for post-adoption services. Adjustment for SNA children is often complicated by traumatic and unstable preadoptive histories that may disrupt the child's sense of security and ability to develop and maintain healthy interpersonal relationships. The purpose of this study was to examine aspects of child functioning related to mental health use among SNA children experiencing difficulty maintaining and developing relationships. A secondary aim of the study was to examine the types of relationship problems that lead caregivers to...

58. Low-Velocity Impact Craters in Ice and Ice-Saturated Sand With Implications for Martian Crater Count Ages - S. K. Croft; S. W. Kieffer; T. J. Ahrens
We produced a series of decimeter-sized impact craters in blocks of ice near 0øC and-70øC and in ice-saturated sand near-70øC as a preliminary investigation of cratering in materials analogous to those found on Mars and the outer solar system satellites. The projectiles used were standard 0.22 and 0.30 caliber bullets fired at velocities between 0.3 and 1.5 km/s, with kinetic energies at impact between 109 and 4 x 10 •ø ergs. Crater diameters in the ice-saturated sand were-•2 times larger than craters in the same energy and velocity range in competent blocks of granite, basalt and cement. Craters in ice...

59. Ground Motions at Memphis and St. Louis from M 7.5–8.0 Earthquakes in the New Madrid Seismic Zone - Gail M. Atkinson; Igor A. Beresnev
Abstract The New Madrid seismic zone is the most important regional seismic hazard in middle America, having produced several very large earthquakes in historic and geologic time. In this study we simulate time histories in Memphis, Tennessee, and St. Louis, Missouri, for M 7.5 and M 8.0 earthquakes along two faults in the New Madrid seismic zone. Simulations are based on a well-established and calibrated finite-fault simulation program (FINSIM), which has been shown to reproduce ground motions for earthquakes of M 4–8 in eastern and western North America (Beresnev and Atkinson, 2001a). Simulations are made for representative soil profiles for...

60. Viscosity effects in vibratory mobilization of residual oil - Igor A. Beresnev; Wen Deng
The last decade has seen clarifications of the underlying capillary physics behind stimulation of oil production by seismic waves and vibrations. Computational studies have prevailed, however, and no viscous hydrodynamic theory of the phenomenon has been proposed. For a body of oil entrapped in a pore channel, viscosity effects are naturally incorporated through a model of two-phase core-annular flow. These effects are significant at the postmobilization stage, when the resistance of capillary forces is overcome and viscosity becomes the only force resisting an oil ganglion’s motion.Aviscous equation of motion follows, and computational fluid dynamics �CFD � establishes the limits of...

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