774 resultados para Logical Relations


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper uses Shannon's information theory to give a quantitative definition of information flow in systems that transform inputs to outputs. For deterministic systems, the definition is shown to specialise to a simpler form when the information source and the known inputs jointly determine the inputs. For this special case, the definition is related to the classical security condition of non-interference and an equivalence is established between non-interference and independence of random variables. Quantitative information flow for deterministic systems is then presented in relational form. With this presentation, it is shown how relational parametricity can be used to derive upper and lower bounds on information flows through families of functions defined in the second order lambda calculus.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper proposes a spatial-temporal downscaling approach to construction of the intensity-duration-frequency (IDF) relations at a local site in the context of climate change and variability. More specifically, the proposed approach is based on a combination of a spatial downscaling method to link large-scale climate variables given by General Circulation Model (GCM) simulations with daily extreme precipitations at a site and a temporal downscaling procedure to describe the relationships between daily and sub-daily extreme precipitations based on the scaling General Extreme Value (GEV) distribution. The feasibility and accuracy of the suggested method were assessed using rainfall data available at eight stations in Quebec (Canada) for the 1961-2000 period and climate simulations under four different climate change scenarios provided by the Canadian (CGCM3) and UK (HadCM3) GCM models. Results of this application have indicated that it is feasible to link sub-daily extreme rainfalls at a local site with large-scale GCM-based daily climate predictors for the construction of the IDF relations for present (1961-1990) and future (2020s, 2050s, and 2080s) periods at a given site under different climate change scenarios. In addition, it was found that annual maximum rainfalls downscaled from the HadCM3 displayed a smaller change in the future, while those values estimated from the CGCM3 indicated a large increasing trend for future periods. This result has demonstrated the presence of high uncertainty in climate simulations provided by different GCMs. In summary, the proposed spatial-temporal downscaling method provided an essential tool for the estimation of extreme rainfalls that are required for various climate-related impact assessment studies for a given region.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Laws of war have been carefully defined by individual nations’ own codes of law as well as by supranational bodies. Yet the international scene has seen an increasing movement away from traditionally declared war toward multinational peacekeeping missions geared at containing local conflicts when perceived as potential threats to their respective regions’ political stability. While individual nations’ laws governing warfare presuppose national sovereignty, the multinational nature of peacekeeping scenarios can blur the lines of command structures, soldiers’ national loyalties, occupational jurisdiction, and raise profound questions as to which countries’ moral sense/governmental system is to be the one upheld. Historically increasingly complex international relations have driven increasingly detailed internationally drafted guidelines for countries’ interactions while at war, yet there are operational, legislative, and moral issues arising in multinational peacekeeping situations which these laws do not address at all. The author analyzes three unique peacekeeping operations in light of these legislative voids and suggests systematic points to consider to the end of protecting the peacekeepers, the national interests of the countries involved, operational matters, and clearly delineating both the objective and logical boundaries of a given multinational peacekeeping mission.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

http://digitalcommons.winthrop.edu/dacusdocsnews/1019/thumbnail.jpg

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The purpose of this article is to discuss the relations between regulation, competition policy and consumer protection these relations in three key sectors of Brazil’s infrastructure: telecommunications, electricity and water supply. A study of the literature points to two general principles. First, the need for consumer protection depends on the “degree of sovereignty” enjoyed by consumers, defined in terms of the cost of consumer organization, consumers’ ability to evaluate services, and the level of competition in each sector. Second, the less sovereignty consumers enjoy the more consumer protection institutions are involved with regulation agencies. The evidence for the Brazilian case apparently corroborates these points. In addition, it is important to stress that consumer complaints in regulated sectors seem to have increased more intensely than in others. The article is divided into three sections. Section 1 presents theoretical elements and aspects of the relations between regulation, competition policy and consumer protection evidenced by international experience. Section 2 analyzes the Brazilian experience and in particular the available statistics on consumer complaints about telecommunications, electricity and water supply, submitted to Fundação Procon-SP during the nineties. The last section points to possible configurations of the institutional relations between competition policy, regulation and consumer protection, showing how the existing configuration of these areas in the three infrastructure sectors discussed confirms that the theoretical framework proposed has reasonable predictive power.