940 resultados para In-network storage


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Die Auszeichnungssprache XML dient zur Annotation von Dokumenten und hat sich als Standard-Datenaustauschformat durchgesetzt. Dabei entsteht der Bedarf, XML-Dokumente nicht nur als reine Textdateien zu speichern und zu transferieren, sondern sie auch persistent in besser strukturierter Form abzulegen. Dies kann unter anderem in speziellen XML- oder relationalen Datenbanken geschehen. Relationale Datenbanken setzen dazu bisher auf zwei grundsätzlich verschiedene Verfahren: Die XML-Dokumente werden entweder unverändert als binäre oder Zeichenkettenobjekte gespeichert oder aber aufgespalten, sodass sie in herkömmlichen relationalen Tabellen normalisiert abgelegt werden können (so genanntes „Flachklopfen“ oder „Schreddern“ der hierarchischen Struktur). Diese Dissertation verfolgt einen neuen Ansatz, der einen Mittelweg zwischen den bisherigen Lösungen darstellt und die Möglichkeiten des weiterentwickelten SQL-Standards aufgreift. SQL:2003 definiert komplexe Struktur- und Kollektionstypen (Tupel, Felder, Listen, Mengen, Multimengen), die es erlauben, XML-Dokumente derart auf relationale Strukturen abzubilden, dass der hierarchische Aufbau erhalten bleibt. Dies bietet zwei Vorteile: Einerseits stehen bewährte Technologien, die aus dem Bereich der relationalen Datenbanken stammen, uneingeschränkt zur Verfügung. Andererseits lässt sich mit Hilfe der SQL:2003-Typen die inhärente Baumstruktur der XML-Dokumente bewahren, sodass es nicht erforderlich ist, diese im Bedarfsfall durch aufwendige Joins aus den meist normalisierten und auf mehrere Tabellen verteilten Tupeln zusammenzusetzen. In dieser Arbeit werden zunächst grundsätzliche Fragen zu passenden, effizienten Abbildungsformen von XML-Dokumenten auf SQL:2003-konforme Datentypen geklärt. Darauf aufbauend wird ein geeignetes, umkehrbares Umsetzungsverfahren entwickelt, das im Rahmen einer prototypischen Applikation implementiert und analysiert wird. Beim Entwurf des Abbildungsverfahrens wird besonderer Wert auf die Einsatzmöglichkeit in Verbindung mit einem existierenden, ausgereiften relationalen Datenbankmanagementsystem (DBMS) gelegt. Da die Unterstützung von SQL:2003 in den kommerziellen DBMS bisher nur unvollständig ist, muss untersucht werden, inwieweit sich die einzelnen Systeme für das zu implementierende Abbildungsverfahren eignen. Dabei stellt sich heraus, dass unter den betrachteten Produkten das DBMS IBM Informix die beste Unterstützung für komplexe Struktur- und Kollektionstypen bietet. Um die Leistungsfähigkeit des Verfahrens besser beurteilen zu können, nimmt die Arbeit Untersuchungen des nötigen Zeitbedarfs und des erforderlichen Arbeits- und Datenbankspeichers der Implementierung vor und bewertet die Ergebnisse.

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Conventional floating gate non-volatile memories (NVMs) present critical issues for device scalability beyond the sub-90 nm node, such as gate length and tunnel oxide thickness reduction. Nanocrystalline germanium (nc-Ge) quantum dot flash memories are fully CMOS compatible technology based on discrete isolated charge storage nodules which have the potential of pushing further the scalability of conventional NVMs. Quantum dot memories offer lower operating voltages as compared to conventional floating-gate (FG) Flash memories due to thinner tunnel dielectrics which allow higher tunneling probabilities. The isolated charge nodules suppress charge loss through lateral paths, thereby achieving a superior charge retention time. Despite the considerable amount of efforts devoted to the study of nanocrystal Flash memories, the charge storage mechanism remains obscure. Interfacial defects of the nanocrystals seem to play a role in charge storage in recent studies, although storage in the nanocrystal conduction band by quantum confinement has been reported earlier. In this work, a single transistor memory structure with threshold voltage shift, Vth, exceeding ~1.5 V corresponding to interface charge trapping in nc-Ge, operating at 0.96 MV/cm, is presented. The trapping effect is eliminated when nc-Ge is synthesized in forming gas thus excluding the possibility of quantum confinement and Coulomb blockade effects. Through discharging kinetics, the model of deep level trap charge storage is confirmed. The trap energy level is dependent on the matrix which confines the nc-Ge.

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Nowadays, Oceanographic and Geospatial communities are closely related worlds. The problem is that they follow parallel paths in data storage, distributions, modelling and data analyzing. This situation produces different data model implementations for the same features. While Geospatial information systems have 2 or 3 dimensions, the Oceanographic models uses multidimensional parameters like temperature, salinity, streams, ocean colour... This implies significant differences between data models of both communities, and leads to difficulties in dataset analysis for both sciences. These troubles affect directly to the Mediterranean Institute for Advanced Studies ( IMEDEA (CSIC-UIB)). Researchers from this Institute perform intensive processing with data from oceanographic facilities like CTDs, moorings, gliders… and geospatial data collected related to the integrated management of coastal zones. In this paper, we present an approach solution based on THREDDS (Thematic Real-time Environmental Distributed Data Services). THREDDS allows data access through the standard geospatial data protocol Web Coverage Service, inside the European project (European Coastal Sea Operational Observing and Forecasting system). The goal of ECOOP is to consolidate, integrate and further develop existing European coastal and regional seas operational observing and forecasting systems into an integrated pan- European system targeted at detecting environmental and climate changes

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Con este trabajo se pretende generar una implementación de una mejora logística que agregue valor, aumente la eficiencia y mejore los procesos de almacenamiento y distribución, gestión del control de inventarios y seguridad industrial de la empresa YOKOMOTOS. Se realizó un estudio profundo de la situación y los problemas que tiene actualmente la empresa. Todo esto con el fin de dar resultados que diferencien a esta compañía en el mercado de los repuestos para motos, obteniendo mayor prestigio y reconocimiento a nivel latinoamericano. De igual forma se establecieron las posibles soluciones que permitieran mitigar estos problemas, mejorando los procesos en el área de almacenamiento, sistema de inventarios y seguridad industrial. Se realizaron diferentes pruebas piloto para analizar la viabilidad de nuestras soluciones, analizando espacios, tiempos y costos. Por último se implementó la mejor solución la cual se ajustó respondiendo a los requerimientos de la compañía, mejorando así los procesos de almacenamiento y distribución agregándole valor a su cadena.

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La liberalización colombiana es analizada, con frecuencia, con los coeficientes de apertura, este documento, en cambio, presenta un análisis complementario a través de algoritmos usados en la teoría de redes para caracterizar sistemas complejos. Esta nueva aproximación devela estructuras de la red mundial de comercio antes y después de la apertura, así como cambios en la posición colombiana.

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La crisis que se desató en el mercado hipotecario en Estados Unidos en 2008 y que logró propagarse a lo largo de todo sistema financiero, dejó en evidencia el nivel de interconexión que actualmente existe entre las entidades del sector y sus relaciones con el sector productivo, dejando en evidencia la necesidad de identificar y caracterizar el riesgo sistémico inherente al sistema, para que de esta forma las entidades reguladoras busquen una estabilidad tanto individual, como del sistema en general. El presente documento muestra, a través de un modelo que combina el poder informativo de las redes y su adecuación a un modelo espacial auto regresivo (tipo panel), la importancia de incorporar al enfoque micro-prudencial (propuesto en Basilea II), una variable que capture el efecto de estar conectado con otras entidades, realizando así un análisis macro-prudencial (propuesto en Basilea III).

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La sepsis es un evento inflamatorio generalizado del organismo inducido por un daño causado generalmente por un agente infeccioso. El patógeno más frecuentemente asociado con esta entidad es el Staphylococcus aureus, responsable de la inducción de apoptosis en células endoteliales debida a la producción de ceramida. Se ha descrito el efecto protector de la proteína C activada (PCA) en sepsis y su relación con la disminución de la apoptosis de las células endoteliales. En este trabajo se analizó la activación de las quinasas AKT, ASK1, SAPK/JNK y p38 en un modelo de apoptosis endotelial usando las técnicas de Western Blotting y ELISA. Las células endoteliales (EA.hy926), se trataron con C2-ceramida (130μM) en presencia de inhibidores químicos de cada una de estas quinasas y PCA. La supervivencia de las células en presencia de inhibidores químicos y PCA fue evaluada por medio de ensayos de activación de las caspasas 3, 7 y 9, que verificaban la muerte celular por apoptosis. Los resultados evidencian que la ceramida reduce la activación de AKT y aumenta la activación de las quinasas ASK, SAPK/JNK y p38, en tanto que PCA ejerce el efecto contrario. Adicionalmente se encontró que la tiorredoxina incrementa la activación/fosforilación de AKT, mientras que la quinasa p38 induce la defosforilación de AKT.

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Para avanzar en el estudio de la concentración espacial de cultivos, se ha elegido el caso de la manzana, la pera y el melocotón en Lleida, desde 1962 a 2000. La evolución de ese fenómeno se ha estudiado mediante técnicas de equilibrio espacial y análisis shift share, encontrándose una pauta espacial de comportamiento distinta entre la manzana y la pera por una parte y el melocotón por otro. En el caso de las técnicas shift share se ha modelado el efecto diferencial como el resultado de un juego de suma nula, y suponiendo que las transferencias de efectos son más probables hacia las regiones más cercanas, se ha avanzado una explicación de las transferencias de superficie que se produjeron entre 1962 y 2000. La diferencia encontrada en el distinto comportamiento espacial de esos cultivos se ha atribuido a la susceptibilidad de cada cultivo para ser conservado frigoríficamente. Se ha desarrollado un modelo que relaciona los incrementos de la capacidad en la industria frigorífica y de la superficie.

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Oil-based formulated conidia sprayed on steel plates and conidia powder (control) of Beauveria bassiana isolate IMI 386243 were stored at temperatures from 10 to 40 degrees C in desiccators over saturated salt solutions providing relative humidities from 32 to 88%, or in hermetic storage at 40 degrees C, and moisture contents in equilibrium with 33 or 77% relative humidity. The negative semi-logarithmic relation (P < 0.005) between conidia longevity (at 40 degrees C) and equilibrium relative humidity did not differ (P > 0.25) between formulated conidia and conidia powder. Despite this, certain saturated salts provided consistently greater longevity (NaCl) and others consistently shorter longevity (KCl) for formulated conidia compared to conidia powder. These results, analysis of previous data, and comparison with hermetic storage, indicate that storage of conidia over saturated salt solutions provides inconsistent responses to environment and so may be problematic for bio-pesticide research. In hermetic storage, oil formulation was not deleterious to longevity and in the more moist environment enhanced survival periods. (c) 2005 Elsevier Inc. All rights reserved.

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The Java language first came to public attention in 1995. Within a year, it was being speculated that Java may be a good language for parallel and distributed computing. Its core features, including being objected oriented and platform independence, as well as having built-in network support and threads, has encouraged this view. Today, Java is being used in almost every type of computer-based system, ranging from sensor networks to high performance computing platforms, and from enterprise applications through to complex research-based.simulations. In this paper the key features that make Java a good language for parallel and distributed computing are first discussed. Two Java-based middleware systems, namely MPJ Express, an MPI-like Java messaging system, and Tycho, a wide-area asynchronous messaging framework with an integrated virtual registry are then discussed. The paper concludes by highlighting the advantages of using Java as middleware to support distributed applications.

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The potential longevity of japonica rice (Oryza sativa L. subsp. japonica) seed is particularly sensitive to high temperature – and thus climate change – during development and maturation. Cultivar Taipei 309 was grown at 28/208C (12 h/12 h) and then from 19 DAA (days after 50% anthesis), when seeds were just over half filled, at 28/208C, 30/228C, 32/248C or 34/268C (12 h/12 h). Whereas ability to germinate ex planta had been achieved in almost all seeds by 24 DAA, only half the population were desiccation tolerant. Desiccation tolerance continued to increase over the subsequent 28 d, similarly at all four temperatures. Subsequent longevity, assessed by p50 (period in days to reduce viability to 50% in hermetic storage at 408C with c. 15% moisture content), increased progressively at 28/208C until 38 DAA, and remained constant until the final harvest (52 DAA). The three warmer temperature regimes provided similar longevity to 28/208C at any one harvest, except at 38 DAA where the warmest (34/268C) was poorer. That temperature regime also provided greater seed-to-seed variability within each survival curve. The results confirm that appreciable improvement in seed quality occurs during seed development and also subsequent maturation in japonica rice, but that increase in temperature from 28/208C to 34/268C during late seed filling onwards has comparatively little effect thereon. Comparison with previous investigations suggests that seed quality development may be less sensitive to high temperatures during late development and maturation than during the early seed development that precedes it.

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The proliferation of artificial container habitats in urban areas has benefitted urban adaptable mosquito species globally. In areas where mosquitoes transmit viruses and parasites, it can promote vector population productivity and fuel mosquito-borne disease outbreaks. In Britain, storage of water in garden water butts is increasing, potentially expanding mosquito larval habitats and influencing population dynamics and mosquito-human contact. Here we show that the community composition, abundance and phenology of mosquitoes breeding in experimental water butt containers were influenced by urbanisation. Mosquitoes in urban containers were less species-rich but present in significantly higher densities (100.4±21.3) per container than those in rural containers (77.7±15.1). Urban containers were dominated by Culex pipiens (a potential vector of West Nile Virus [WNV]) and appear to be increasingly exploited by Anopheles plumbeus (a human-biting potential WNV and malaria vector). Culex phenology was influenced by urban land use type, with peaks in larval abundances occurring earlier in urban than rural containers. Among other factors, this was associated with an urban heat island effect which raised urban air and water temperatures by 0.9°C and 1.2°C respectively. Further increases in domestic water storage, particularly in urban areas, in combination with climate changes will likely alter mosquito population dynamics in the UK.

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Climate projections show Australia becoming significantly warmer during the 21st century, and precipitation decreasing over much of the continent. Such changes are conventionally considered to increase wildfire risk. Nevertheless, we show that burnt area increases in southern Australia, but decreases in northern Australia. Overall the projected increase in fire is small (0.72–1.31% of land area, depending on the climate scenario used), and does not cause a decrease in carbon storage. In fact, carbon storage increases by 3.7–5.6 Pg C (depending on the climate scenario used). Using a process-based model of vegetation dynamics, vegetation–fire interactions and carbon cycling, we show increased fire promotes a shift to more fire-adapted trees in wooded areas and their encroachment into grasslands, with an overall increase in forested area of 3.9–11.9%. Both changes increase carbon uptake and storage. The increase in woody vegetation increases the amount of coarse litter, which decays more slowly than fine litter hence leading to a relative reduction in overall heterotrophic respiration, further reducing carbon losses. Direct CO2 effects increase woody cover, water-use efficiency and productivity, such that carbon storage is increased by 8.5–14.8 Pg C compared to simulations in which CO2 is held constant at modern values. CO2 effects tend to increase burnt area, fire fluxes and therefore carbon losses in arid areas, but increase vegetation density and reduce burnt area in wooded areas.

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Biocomposites with two different fillers, garlic and wheat bran, were studied. They were based on cassava starch and contained glycerol as a plasticizer and potassium sorbate as an antimicrobial agent and were characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and infrared spectroscopy (IR). The mechanical performance at room and lower temperatures was also studied. SEM micrographies of fractured surfaces of the wheat bran composite films showed some ruptured particles of fiber while fibrils of garlic on the order of nanometers were observed when garlic composite films were studied. Mechanical tests, at room temperature, showed that the addition of wheat bran led to an increment in the storage modulus (E`) and hardening and a decrease in Tan delta, while the garlic composite showed a diminishing in the E` and hardening and did not produce significant changes in Tan delta values when compared with systems without fillers (matrix). In the range between -90 degrees C and 20 degrees C. all the materials studied presented two peaks in the Tan delta curve. In the case of the wheat bran composite, both relaxation peaks shifted slightly to higher temperatures, broadened and diminished their intensity when compared with those of the matrix; however garlic composite showed a similar behavior to the matrix. DSC thermograms of aqueous systems showed a slight shift of gelatinization temperature (T(gelatinization)) to higher values when the fillers were present. Thermograms of films showed that both, garlic and wheat bran composites, had a lower melting point than the matrix. IR data indicated that interaction between starch and fillers determined an increase in the availability of hydroxyl groups to be involved in a dynamic exchange with water. (C) 2010 Elsevier B.V. All rights reserved.

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Tannin-phenolic polymers prepared using tannin, a macromolecule obtained from natural sources, were used in the preparation of composites reinforced with coir fibers. The composites based on tannin-phenolic polymers (50% (w/w) of tannin as substitute of the phenol) were prepared using the coir fibers as reinforcement (30-70% (w/w), 3.0-6.0 cm, randomly distributed). The Izod impact strength of the composites showed an improvement in this property due to the incorporation of coir fibers in the tannin-phenolic matrices. The SEM images showed excellent adhesion at the fiber/matrix interface. The coir fiber had bundles regularly spaced, which enhanced the diffusion of the resin into the fiber. In addition, the high lignin content of this fiber results in a high concentration of aromatic rings, which increased the compatibility with the matrix. The values of the diffusion coefficient of water, determined using Fick`s laws, show that there was no correlation between the fiber percentage and the water diffusion. The DMTA curves showed that the storage moduli of the composites reinforced with coir fibers were considerably higher than that of the thermoset, and the increase in the proportion of fibers led to a proportional increase in the storage moduli of these materials. The biobased composites obtained have potential for non-structural applications, such as in the internal parts of automotives vehicles. To our knowledge, this is the first study on this kind of biobased composites. (C) 2010 Elsevier B.V. All rights reserved.