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101.
In 2000, for the first time, the number of minimum income allocation system (RMI) recipients decreased. In 2001, this drop in the number of recipients began to stabilize, and the number started to increase again in 2002.The author observed a stabilization of the number of new recipients, whereas the number of exits decreased. This situation is different according to local countries (departments). The probability of RMI entries is more important for populations living in the south and southeast of France. RMI recipients of the more recent cohorts leave more quickly and in proportion more significantly than do the recipients of the older cohorts. This phenomenon is alarming because the exits occur massively during the first 2 years spent in the RMI device and because the probability of leaving decreases sharply. The author has thus observed that a significant portion of the recipients (28%) is present after 5 years or more in the RMI device.  相似文献   
102.
103.
This paper examines the impacts, feedbacks, and mitigation of the urban heat island in Phoenix, Arizona (USA). At Sky Harbor Airport, urbanization has increased the nighttime minimum temperature by 5°C and the average daily temperatures by 3.1°C. Urban warming has increased the number of misery hours per day for humans, which may have important social consequences. Other impacts include (1) increased energy consumption for heating and cooling of buildings, (2) increased heat stress (but decreased cold stress) for plants, (3) reduced quality of cotton fiber and reduced dairy production on the urban fringe, and (4) a broadening of the seasonal thermal window for arthropods. Climate feedback loops associated with evapotranspiration, energy production and consumption associated with increased air conditioning demand, and land conversion are discussed. Urban planning and design policy could be redesigned to mitigate urban warming, and several cities in the region are incorporating concerns regarding urban warming into planning codes and practices. The issue is timely and important, because most of the world's human population growth over the next 30 years will occur in cities in warm climates.  相似文献   
104.
Remote sensing is a helpful tool for crop monitoring or vegetation-growth estimation at a country or regional scale. However, satellite images generally have to cope with a compromise between the time frequency of observations and their resolution (i.e. pixel size). When concerned with high temporal resolution, we have to work with information on the basis of kilometric pixels, named mixed pixels, that represent aggregated responses of multiple land cover. Disaggreggation or unmixing is then necessary to downscale from the square kilometer to the local dynamic of each theme (crop, wood, meadows, etc.).

Assuming the land use is known, that is to say the proportion of each theme within each mixed pixel, we propose to address the downscaling issue through the generalization of varying-time regression models for longitudinal data and/or functional data by introducing random individual effects. The estimators are built by expanding the mixed pixels trajectories with B-splines functions and maximizing the log-likelihood with a backfitting-ECME algorithm. A BLUP formula allows then to get the ‘best possible’ estimations of the local temporal responses of each crop when observing mixed pixels trajectories. We show that this model has many potential applications in remote sensing, and an interesting one consists of coupling high and low spatial resolution images in order to perform temporal interpolation of high spatial resolution images (20 m), increasing the knowledge on particular crops in very precise locations.

The unmixing and temporal high-resolution interpolation approaches are illustrated on remote-sensing data obtained on the South-Western France during the year 2002.  相似文献   

105.
The objective of this article is to explore the factors that influence parental risk perceptions of child pedestrian injuries in the elementary school context. Parents (n= 193) from six different schools responded to a questionnaire on road safety, including a measure of their risk perception. Results of bivariate analyses show that eight variables are significantly related to risk perception. Environmental variables, as we measure them, were not significant, contrary to our initial hypotheses. Only three variables, parent's gender, perceived primary source of danger, and sense of control remained significant in OLS regression analyses (adjusted R2 of 0.16, F= 9.27; p= 0.00). Since parents’ perceptions of road risks are an important factor in their road safety practices and in their choice of transportation mode used for their child's journey to school, our analysis elucidates factors underlying these choices. Our results can help decisionmakers to design traffic injury prevention measures and to promote physical activity through the use of active modes of transport.  相似文献   
106.
This article analyses the health care system reform process in Europe based on the concept of privatization. This notion is understood from two perspectives. First, privatization may concern the health care financing or the provision of health services. Second, privatization can be “imposed” on individuals or be “internalized” and then introduced by individuals (patients and doctors). So we emphasize the diversity that privatization can assume. We classify privatization mechanisms used by different countries and identify which of the perspectives presented are more common in 14 European Union countries since the 1980s. The article shows that even if privatization processes are widespread, they assume different patterns in each country.  相似文献   
107.
In this paper we explain how practitioners perform strategic sensemaking with visual representations. Here, we identify four modes of strategic sensemaking/giving: content‐generating, process‐generating, process‐ingraining and content‐ingraining. While each of these modes supports strategic sensemaking/giving by focusing practitioners’ work on specific issues, they also divert practitioners from focusing on key aspects of strategy making. We conceptualize these limitations as ‘blind spots’. As a result, strategic sensemaking appears fragmented and can lead to breakdowns in sensemaking. However, the flexibility of visual representations facilitates strategic sensemaking by allowing practitioners to switch from one mode to another. These findings improve our understanding of the strategic sensemaking/giving practices that are associated with the use of visual representation.  相似文献   
108.
Women 65 years old and over make up the fastest growing population segment in North America. They are, particularly among the underprivileged, known to be heavy consumers of prescribed and over-the-counter drugs. The objective of this study was to identify the role of medication in underprivileged elderly women's strategies for aging well and dealing with minor health problems. A qualitative study was conducted among 40 women aged 65 to 75. Results show that elderly women seldom mention resorting to medication to "age well" although they report using this strategy to deal with minor health problems. Overall, the elderly women mentioned a wide range of strategies to cope with aging and minor health problems, which suggests that they are well equipped to face the challenges of aging.  相似文献   
109.
This note complements the study of Burke, Carillo, and Vakharia ( 2009 hereafter “BCV”) which analyzes a class of single‐product multisourcing problems under stochastic demand and random yields. The purpose is twofold. First, we prove that the objective function used by these authors is only a lower bound for the expected profit for which we provide the correct expression. Second, we show on some of the numerical instances provided in BCV's study that the structure and the performance of the BCV ordering policy may be substantially different from the optimal ordering policy. We conclude by giving general qualitative insights characterizing suboptimality of the BCV solution.  相似文献   
110.
The paper extends a result in Dutta and Ray's (1989) theory of constrained egalitarianism initiated by relying on the concept of proportionate rather than absolute equality. We apply this framework to redistributive systems in which what the individuals get depends on what they receive or pay qua members of generally overlapping groups. We solve the constrained equalization problem for this class of models. The paper ends up comparing our solution with the alternative solution based on the Shapley value, which has been recommended in some distributive applications.  相似文献   
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