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1.
In this article, the authors review and analyse two key processes conducted by the Chilean state over the past 50 years. The first process consists of the development of specific planning instruments for the particular realities of metropolitan areas. The second process consists of the successive legislative attempts to work towards a definition of a new form of institutionality for cities with metropolitan profiles. These attempts have either failed or solely become bills of law. Both processes suggest a political and technical resistance throughout history, to substantially modify institutionality, as well as planning instruments, in order to make them more appropriate and consistent with the needs of growing metropolitan areas in Chile.  相似文献   
2.
Personal Protective Equipment (PPE) is considered the last preferred solution to an Occupational Safety Health (OSH) system. Brazilian OSH legislation assumes and requires PPE usage to neutralize the possibility of pesticide contamination. This study examines the inadequacy of the PPE used in a tomato crop, particularly from the standpoint of thermal comfort. This study made observations regarding heart rate and body temperature in a controlled environment using a treadmill (with and without PPE) of 12 volunteers; and during the process of rural labor (at rest and in normal work routine) of 2 actual rural workers. Comparing the results of the treadmill test (with and without PPE) which tried to reproduce the same level of effort and environmental conditions of the actual rural work, this study demonstrated that PPE makes thermoregulation harder and tympanic temperature reaches higher values with the same level of effort. Moreover, body temperature increases quickly: with PPE it took 15 minutes to raise 1°C in body temperature, compared to 40 minutes without PPE. The results of this study indicated that the use inadequate PPE might pose thermoregulation risk to rural workers.  相似文献   
3.
Global sensitivity analysis with variance-based measures suffers from several theoretical and practical limitations, since they focus only on the variance of the output and handle multivariate variables in a limited way. In this paper, we introduce a new class of sensitivity indices based on dependence measures which overcomes these insufficiencies. Our approach originates from the idea to compare the output distribution with its conditional counterpart when one of the input variables is fixed. We establish that this comparison yields previously proposed indices when it is performed with Csiszár f-divergences, as well as sensitivity indices which are well-known dependence measures between random variables. This leads us to investigate completely new sensitivity indices based on recent state-of-the-art dependence measures, such as distance correlation and the Hilbert–Schmidt independence criterion. We also emphasize the potential of feature selection techniques relying on such dependence measures as alternatives to screening in high dimension.  相似文献   
4.
One of the characteristics of modern industrial development is the emergence of a new typology of accidents whose effects can be spread, in space as well as in time, well beyond the borders of the installations where they occur, sometimes impacting the local population and the environment in a catastrophic fashion. This is the result of a number of factors that have changed the risk profile of modern industrial activities. For a number of reasons, the developing countries have proved to be more vulnerable to industrial disasters. Three of the most catastrophic industrial accidents—Bhopal, San Juan de Ixhuatepec, and Cubatão—occurred in developing countries, claiming thousands of lives. During the 1970s and 1980s the higher degree of public visibility of industrial hazards as a result of serious accidents, led to the creation, especially in the more industrialized countries, of regulations for greater control over industrial activities, either by means of new laws or by updating existing legislation. Some of these regulations were designed to improve the response to accidents with potential impacts outside the industrial sites. This article attempts to describe the current status and identify the shortcomings of off‐site emergency planning for hazardous industrial areas in Brazil. The most important problems are the lack of specific legislation and the absence of awareness and active participation of public authorities. The experience of an off‐site emergency planning process for a Brazilian industrial area is presented. This experience illustrates how difficult it is to prepare and implement emergency planning processes in an industrializing country.  相似文献   
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Lopez A 《Demography》1967,4(2):453-463
Significant efforts in the field of study and control of reproductive habits of the Colombian population have been made in the last few years by local medical groups. This article attempts to illustrate how the data obtained in this program can be meaningfully exploited from the demographic point of view. Although data available at the time of writing did not comply with the principles of scientific sampling procedures, it is thought that such studies can throw some light on particular issues, such as the patterns of mating, the effect of contraception on birth spacing among married couples, and the relation of fecundity to frequency of coitus. This article deals with some methodological issues which center around these problems.  相似文献   
7.
Blume and Easley (1992) show that if agents' have the same savings rule, those who maximize the expected logarithm of next period's outcomes will eventually hold all wealth (i.e. are ‘most prosperous’). However, if no agent adopts this rule then the most prosperous are not necessarily those who make the most accurate predictions. Thus, agents who make inaccurate predictions need not be driven out of the market. In this paper, it is shown that, among agents who have the same intertemporal discount factor (and who choose savings endogenously), the most prosperous are those who make accurate predictions. Hence, convergence to rational expectations obtains because agents who make inaccurate predictions are driven out of the market.  相似文献   
8.
The global sensitivity analysis method used to quantify the influence of uncertain input variables on the variability in numerical model responses has already been applied to deterministic computer codes; deterministic means here that the same set of input variables always gives the same output value. This paper proposes a global sensitivity analysis methodology for stochastic computer codes, for which the result of each code run is itself random. The framework of the joint modeling of the mean and dispersion of heteroscedastic data is used. To deal with the complexity of computer experiment outputs, nonparametric joint models are discussed and a new Gaussian process-based joint model is proposed. The relevance of these models is analyzed based upon two case studies. Results show that the joint modeling approach yields accurate sensitivity index estimators even when heteroscedasticity is strong.  相似文献   
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10.
Lopez A 《Demography》1967,4(2):680-687
A useful and intuitively appealing proposition in theoretical demography asserts that the age distribution of a closed human populationis asymptotically independent of this shapein thedistant past, and is therefore exclusively determined by the historyof fertility and mortalitythat has prevailed during a reasonably long period of time. The mathematical foundations of this ergodic principle arelaid out in this article and thedetailsof its proofareworked out afteremphasizing an intuitive understanding of the process through which an age distribution tends to "forget" its past. The tendency for an unchanging schedule of vital ratesto produce a fixed agestructure in a closed population, is presented as a corollary of the main proposition dealt with in this article.  相似文献   
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