923 resultados para other issues


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During Leg 188 of the Ocean Drilling Program (ODP), employing JOIDES Resolution, we drilled holes at three sites in the southern Indian Ocean in and near Prydz Bay, East Antarctica, between 28 January and 29 February 2000. The objectives of the voyage were to: - Core through sediments deposited when Antarctica underwent the transition from "greenhouse" to the modern "icehouse" state late in the Eocene or early in the Oligocene, at sites obtaining their sediment from the currently subglacial Gamburtsev Mountains that probably were the site of nucleation of the ice sheet (principally Site 1166); - Obtain a sediment record from times at which major changes in the ice sheet volume and characteristics took place as judged from oxygen isotope records, especially at ~23.7 Ma (Oligocene/Miocene boundary), 12-16 Ma (middle Miocene), and 2.7 Ma (late Pliocene) (mainly Site 1165); and - Sample through the upper Pliocene and Quaternary in an attempt to document fluctuations in the extent of the ice sheet over the continental shelf during the Quaternary (especially Site 1167). Paleogene foraminifer-bearing marine sections were not intersected, and thus discussion of marine sections is restricted to the Neogene. Foraminifers are not major contributors to Leg 188 chronostratigraphy but contribute to paleoenvironmental interpretation, to issues such as carbonate compensation depth (CCD) effects and source and history of sediment, and provide a basis for Sr and d18O studies. Chronostratigraphy for the various sections was compiled from diatoms, radiolarians, and paleomagnetism (Shipboard Scientific Party, 2001, doi:10.2973/odp.proc.ir.188.101.2001). Foraminifers were sporadic rather than continuous except in short intervals; however, the Neogene foraminifers from the region are very poorly known and the new records proved to be of significant value in paleoenvironmental interpretation. Only at Site 1167 did drilling intersect a section that yielded foraminifers virtually throughout. Other than for the very young section at each site, there is virtually no continuity of assemblages between sites and thus each section is treated here as separate and unrelated.

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Despite widespread interest in China's growing trade surplus and its impact on other countries, empirical research in these issues is handicapped by the lack of reliable statistics on aggregate import and export prices. Although researchers estimate the trade volumes of China and other East Asian countries using a variety of surrogate price indices, an inappropriate deflator can give rise to a significant bias in econometric analysis. This paper discusses the potential seriousness of this problem by examining recent studies on the export competition between China and other Asian countries.

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The use of cloud computing is extending to all kind of systems, including the ones that are part of Critical Infrastructures, and measuring the reliability is becoming more difficult. Computing is becoming the 5th utility, in part thanks to the use of cloud services. Cloud computing is used now by all types of systems and organizations, including critical infrastructure, creating hidden inter-dependencies on both public and private cloud models. This paper investigates the use of cloud computing by critical infrastructure systems, the reliability and continuity of services risks associated with their use by critical systems. Some examples are presented of their use by different critical industries, and even when the use of cloud computing by such systems is not widely extended, there is a future risk that this paper presents. The concepts of macro and micro dependability and the model we introduce are useful for inter-dependency definition and for analyzing the resilience of systems that depend on other systems, specifically in the cloud model.

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Visualization of program executions has been found useful in applications which include education and debugging. However, traditional visualization techniques often fall short of expectations or are altogether inadequate for new programming paradigms, such as Constraint Logic Programming (CLP), whose declarative and operational semantics differ in some crucial ways from those of other paradigms. In particular, traditional ideas regarding flow control and the behavior of data often cannot be lifted in a straightforward way to (C)LP from other families of programming languages. In this paper we discuss techniques for visualizing program execution and data evolution in CLP. We briefly review some previously proposed visualization paradigms, and also propose a number of (to our knowledge) novel ones. The graphical representations have been chosen based on the perceived needs of a programmer trying to analyze the behavior and characteristics of an execution. In particular, we concéntrate on the representation of the program execution behavior (control), the runtime valúes of the variables, and the runtime constraints. Given our interest in visualizing large executions, we also pay attention to abstraction techniques, Le., techniques which are intended to help in reducing the complexity of the visual information.

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A Kuhnian approach to research assessment requires us to consider that the important scientific breakthroughs that drive scientific progress are infrequent and that the progress of science does not depend on normal research. Consequently, indicators of research performance based on the total number of papers do not accurately measure scientific progress. Similarly, those universities with the best reputations in terms of scientific progress differ widely from other universities in terms of the scale of investments made in research and in the higher concentrations of outstanding scientists present, but less so in terms of the total number of papers or citations. This study argues that indicators for the 1% high-citation tail of the citation distribution reveal the contribution of universities to the progress of science and provide quantifiable justification for the large investments in research made by elite research universities. In this tail, which follows a power low, the number of the less frequent and highly cited important breakthroughs can be predicted from the frequencies of papers in the upper part of the tail. This study quantifies the false impression of excellence produced by multinational papers, and by other types of papers that do not contribute to the progress of science. Many of these papers are concentrated in and dominate lists of highly cited papers, especially in lower-ranked universities. The h-index obscures the differences between higher- and lower-ranked universities because the proportion of h-core papers in the 1% high-citation tail is not proportional to the value of the h-index.

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Although numerous modelling efforts have integrated food and water considerations at the farm or river basin level, very few agro-economic models are able to jointly assess water and food policies at the global level. The present report explores the feasibility of integrating water considerations into the CAPRI model. First, a literature review of modelling approaches integrating food and water issues has been conducted. Three agro-economic models, IMPACT, WATERSIM and GLOBIOM, have been analysed in detail. In addition, biophysical and hydrological models estimating agricultural water use have also been studied, in particular the global hydrological model WATERGAP and the LISFLOOD model. Thanks to the programming approach of its supply module, CAPRI shows a high potentiality to integrate environmental indicators as well as to enter new resource constraints (land potentially irrigated, irrigation water) and input-output relationships. At least in theory, the activity-based approach of the regional programming model in CAPRI allows differentiating between rainfed and irrigated activities. The suggested approach to include water into the CAPRI model involves creating an irrigation module and a water use module. The development of the CAPRI water module will enable to provide scientific assessment on agricultural water use within the EU and to analyze agricultural pressures on water resources. The feasibility of the approach has been tested in a pilot case study including two NUTS 2 regions (Andalucia in Spain and Midi-Pyrenees in France). Preliminary results are presented, highlighting the interrelations between water and agricultural developments in Europe. As a next step, it is foreseen to further develop the CAPRI water module to account for competition between agricultural and non-agricultural water use. This will imply building a water use sub-module to compute water use balances.

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Thin film photovoltaic (TF) modules have gained importance in the photovoltaic (PV) market. New PV plants increasingly use TF technologies. In order to have a reliable sample of a PV module population, a huge number of modules must be measured. There is a big variety of materials used in TF technology. Some of these modules are made of amorphous or microcrystalline silicon. Other are made of CIS or CdTe. Not all these materials respond the same under standard test conditions (STC) of power measurement. Power rates of the modules may vary depending on both the extent and the history of sunlight exposure. Thus, it is necessary a testing method adapted to each TF technology. This test must guarantee repeatability of measurements of generated power. This paper shows responses of different commercial TF PV modules to sunlight exposure. Several test procedures were performed in order to find the best methodology to obtain measurements of TF PV modules at STC in the easiest way. A methodology for indoor measurements adapted to these technologies is described.

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Scaling is becoming an increasingly important topic in the earth and environmental sciences as researchers attempt to understand complex natural systems through the lens of an ever-increasing set of methods and scales. The guest editors introduce the papers in this issue’s special section and present an overview of some of the work being done. Scaling remains one of the most challenging topics in earth and environmental sciences, forming a basis for our understanding of process development across the multiple scales that make up the subsurface environment. Tremendous progress has been made in discovery, explanation, and applications of scaling. And yet much more needs to be done and is being done as part of the modern quest to quantify, analyze, and manage the complexity of natural systems. Understanding and succinct representation of scaling properties can unveil underlying relationships between system structure and response functions, improve parameterization of natural variability and heterogeneity, and help us address societal needs by effectively merging knowledge acquired at different scales.

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Is it profitable for an investor, from a risk-return perspective, to acquire a stake in a quoted company when a capital increase is announced? This paper analyses the return obtained from the investment in equity issues with cash contribution and pre-emptive rights, aimed at funding corporate activities: acquisitions, investments in new facilities and/or strengthening the balance sheet of the companies undertaking the equity issue. During the 16 years covered by the study, the results show a negative average excess risk-adjusted return of almost 5%, from the moment that the equity offer is announced until the completion of the preferential subscription period. To obtain this excess return, the difference between the nominal Internal Rate of Return (IRR) and the expected return, using the CAPM, is computed for each equity issue. The intention behind this method is to eliminate the effects of time and any other possible effect on the stock price during the period of the analysis.The results from this article are consistent with the Pecking Order theory for the Spanish Stock Market also six months after the preferential subscription period. However, there is a positive return after three months.

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Water quantity and quality issues worldwide are causing nations to consider alternate sources for drinking water. Desalination and other membrane processes for treatment of seawater and brackish inland waters have been in use for the past quarter century and are growing in use worldwide. These treatment processes create a highly concentrated waste stream in which the principal constituents are dissolved solids. This report provides an overview of desalination methods and the methods available to dispose of this waste stream. Innovative technologies being studied for possible future use are also discussed.

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The National School Lunch Program (NSLP) has undergone profound changes since its establishment in the 1930s with a primary goal of feeding undernourished school children. Today, the program is under scrutiny for its negative impact on student health and environmental unsustainability. This project investigates the origins of the NSLP, the current status of the program, and opportunities for reform. In view of the program's deficiencies, much can be learned by studying other relevant models for school lunch, such as those used in Italy and France. While recognizing the political realities and budgetary constraints public schools currently confront, the Business Plan applies these lessons in its proposals for rethinking the school lunch program at one Denver public school.

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The purpose of this dissertation is to give a contribution to the translation of the terminology of Cycle and Bike Polo into European Portuguese and hence call the attention of a wide Portuguese public to this fairly new sport, whose roots go back to Elephant and Horse Polo in India and in other parts of the world. Sequencing a characterization of technical translation, translation issues of Bike and Cycle Polo´s terminological units have been dealt with in the light of the Cognitive Linguistics framework and hence intimately associated both with physical experiences and historical facts. In fact, sports terminology coinage in this field is highly motivated by metaphorical and metonymical conceptualization mapped from physical reality dimensions, as well as from already existing sports terminology from other sports modalities. In order to render this research unique, a glossary of technical terms from Bike and Cycle Polo has been gathered, since most of them had not yet undergone translation from English into European Portuguese. For validation of my translations I have resorted to Portuguese bike polo players, with special reference to Catarina Almeida, who introduced me to Bike Polo’s terminology.