940 resultados para weak consistency


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Domestic animals have played a key role in human history. Despite their importance, however, the origins of most domestic species remain poorly understood. We assessed the phylogenetic history and population structure of domestic goats by sequencing a hypervariable segment (481 bp) of the mtDNA control region from 406 goats representing 88 breeds distributed across the Old World. Phylogeographic analysis revealed three highly divergent goat lineages (estimated divergence >200,000 years ago), with one lineage occurring only in eastern and southern Asia. A remarkably similar pattern exists in cattle, sheep, and pigs. These results, combined with recent archaeological findings, suggest that goats and other farm animals have multiple maternal origins with a possible center of origin in Asia, as well as in the Fertile Crescent. The pattern of goat mtDNA diversity suggests that all three lineages have undergone population expansions, but that the expansion was relatively recent for two of the lineages (including the Asian lineage). Goat populations are surprisingly less genetically structured than cattle populations. In goats only ≈10% of the mtDNA variation is partitioned among continents. In cattle the amount is ≥50%. This weak structuring suggests extensive intercontinental transportation of goats and has intriguing implications about the importance of goats in historical human migrations and commerce.

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Oscillating electric fields can be rectified by proteins in cell membranes to give rise to a dc transport of a substance across the membrane or a net conversion of a substrate to a product. This provides a basis for signal averaging and may be important for understanding the effects of weak extremely low frequency (ELF) electric fields on cellular systems. We consider the limits imposed by thermal and "excess" biological noise on the magnitude and exposure duration of such electric field-induced membrane activity. Under certain circumstances, the excess noise leads to an increase in the signal-to-noise ratio in a manner similar to processes labeled "stochastic resonance." Numerical results indicate that it is difficult to reconcile biological effects with low field strengths.

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We examine the predictive ability and consistency properties of exchange rate expectations for the dollar/euro using a survey conducted in Spain by PwC among a panel of experts and entrepreneurs. Our results suggest that the PwC panel have some forecasting ability for time horizons from 3 to 9 months, although only for the 3-month ahead expectations we obtain marginal evidence of unbiasedness and efficiency in the forecasts. As for the consistency properties of the exchange rate expectations formation process, we find that survey participants form stabilising expectations in the short-run and destabilising expectations in the long- run and that the expectation formation process is closer to fundamentalists than chartists.

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The thermodynamic consistency of almost 90 VLE data series, including isothermal and isobaric conditions for systems of both total and partial miscibility in the liquid phase, has been examined by means of the area and point-to-point tests. In addition, the Gibbs energy of mixing function calculated from these experimental data has been inspected, with some rather surprising results: certain data sets exhibiting high dispersion or leading to Gibbs energy of mixing curves inconsistent with the total or partial miscibility of the liquid phase, surprisingly, pass the tests. Several possible inconsistencies in the tests themselves or in their application are discussed. Related to this is a very interesting and ambitious initiative that arose within the NIST organization: the development of an algorithm to assess the quality of experimental VLE data. The present paper questions the applicability of two of the five tests that are combined in the algorithm. It further shows that the deviation of the experimental VLE data from the correlation obtained by a given model, the basis of some point-to-point tests, should not be used to evaluate the quality of these data.

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Thermodynamics Conference 2013 (Statistical Mechanics and Thermodynamics Group of the Royal Society of Chemistry), The University of Manchester, 3-6 September 2013.

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This paper proposes a new feature representation method based on the construction of a Confidence Matrix (CM). This representation consists of posterior probability values provided by several weak classifiers, each one trained and used in different sets of features from the original sample. The CM allows the final classifier to abstract itself from discovering underlying groups of features. In this work the CM is applied to isolated character image recognition, for which several set of features can be extracted from each sample. Experimentation has shown that the use of CM permits a significant improvement in accuracy in most cases, while the others remain the same. The results were obtained after experimenting with four well-known corpora, using evolved meta-classifiers with the k-Nearest Neighbor rule as a weak classifier and by applying statistical significance tests.

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Tese de mestrado integrado em Engenharia da Energia e do Ambiente, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2016

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This paper analyses the recent process of state decentralisation in Italy from the perspectives of political science and constitutional law. It considers the conflicting pressures and partisan opportunism of the decentralising process, and how these have adversely affected the consistency and completeness of the new constitutional framework. The paper evaluates the major institutional reforms affecting state decentralisation, including the 2001 constitutional reform and the more recent legislation on fiscal federalism. It argues that while the legal framework for decentralisation remains unclear and contradictory in parts, the Constitutional Court has performed a key role in interpreting the provisions and giving life to the decentralised system, in which regional governments now perform a much more prominent role. This new system of more decentralised multi-level government must nevertheless contend with a political culture and party system that remains highly centralised, while the administrative apparatus has undergone no comparable shift to take account of state decentralisation, leading to the duplication of bureaucracy at all territorial levels and continuing conflicts over policy jurisdiction. Unlike in federal systems these conflicts cannot be resolved in Italy through mechanisms of “shared rule”, since formal inter-governmental coordination structure are weak and entirely consultative.

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Banks in the northern eurozone have capital ratios that are, on average, less than half of the capital ratios of banks in the eurozone’s periphery. The authors explain this by the fact that northern eurozone banks profit from the financial solidity of their governments and follow business strategies aimed at issuing too much subsidised debt. In doing so, they weaken their balance sheets and become more fragile – less able to withstand future shocks. Paradoxically, financially strong governments breed fragile banks. The opposite occurs in countries with financially weak governments. In these countries banks are forced to strengthen themselves because they are unable to rely on their governments. As a result they have significantly more capital and reserves than banks in the northern eurozone. Recommendations More than in the south, the governments of northern Europe should stand up and force the banks to issue more equity. This should go much further than what is foreseen in the Basel III accord. If the experience of the southern eurozone countries is any guide, banks in the north of the eurozone should at least double the capital and the reserves as a percentage of their balance sheets. Failure to do so risks destroying the financial solidity of the northern European governments when, in the future, negative shocks force these governments to come to the rescue of their undercapitalised banks. The new responsibilities entrusted to the European Central Bank as the single supervisor in the eurozone create a unique opportunity for that institution to change the regulatory and supervisory culture in the eurozone – one that has allowed the large banks to continue living dangerously, with insufficient capital.

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There are clear benefits to price stability. High inflation can distort corporate investment decisions and the consumption behaviour of households. Changes to inflation redistribute real wealth and income between different segments of society, such as savers and borrowers, or young and old. Price stability is therefore a fundamental public good and it became a fundamental principle of European Economic and Monetary Union. But the European Treaties do not define price stability. It was left to the Governing Council of the European Central Bank (ECB) to quantify it: "Price stability is defined as a year-on-year increase in the Harmonised Index of Consumer Prices (HICP) for the euro area of below 2%"[1]. The Governing Council has also clarified that it aims to maintain inflation below, but close to, two percent over the medium term, though it has not quantified what 'closeness' means, nor has it given a precise definition of the 'medium term'[2]. The clarification has been widely interpreted to mean that the actual target of the ECB is close to, but below, two percent inflation in the medium term.

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The political, military and economic parameters of German power influence the vision of the international order that Berlin favours. Politically, Germany is a regional power in the EU with considerable diplomatic potential. Economically, it is the world's third largest power with growing global trade and investment links. At the same time, Germany's military potential is limited and the German strategic culture makes the country sceptical about the use of military instruments. Berlin is thus essentially interested in maintaining peace and stability, both in Europe and globally, and in developing diplomatic mechanisms to manage regional and global crises and conflicts. The German preference for dialogue and compromise in conflict situations in the regional and global dimensions may increasingly pose a risk to maintaining the cohesion and credibility of NATO – both from the perspective of the USA and Germany’s allies from Central-Eastern and Northern Europe.

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Software architecture erodes over time and needs to be constantly monitored to be kept consistent with its original intended design. Consistency is rarely monitored using automated techniques. The cost associated to such an activity is typically not considered proportional to its benefits. To improve this situation, we propose Dicto, a uniform DSL for specifying architectural invariants. This language is designed to reduce the cost of consistency checking by offering a framework in which existing validation tools can be matched to newly-defined language constructs. In this paper we discuss how such a DSL can be qualitatively and qualitatively evaluated in practice.

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Federal Highway Administration, Environmental Division, Washington, D.C.