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This paper describes the theory, data, and methodology necessary for using Fisher information to assess the sustainability of the San Luis Basin (SLB) regional system over time. Fisher information was originally developed as a measure of the information content in data and is an important method in information theory. Our adaptation of Fisher information provides a means of monitoring the variables of a system to characterize dynamic order, and, therefore, its regimes and regime shifts. This work is part of the SLB Sustainability Metrics Project, which aimed to evaluate movement over time towards or away from regional sustainability. One of the key goals of this project was to use readily available data to assess the sustainability of the system including its environmental, social and economic aspects. For this study, Fisher information was calculated for fifty-three variables which characterize the consumption of food and energy, agricultural production, environmental characteristics, demographic properties and changes in land use for the SLB system from 1980 to 2005. Our analysis revealed that while the system displayed small changes in dynamic order over time with a slight decreasing trend near the end of the period, there is no indication of a regime shift. Therefore, the SLB system is stable with very slight movement away from sustainability in more recent years.  相似文献   
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The interaction of North Brazil Current (NBC) rings with the Lesser Antilles Arc (LAA) and the Barbados Island (BI) is addressed by experimental modeling and observations. Our results compare well with previous experimental results and numerical simulations. Several sizes, intensities and two different vorticity profiles (non-isolated and initially isolated vortices) were tested. Three regimes were found namely: (1) the vortex surrounds the BI and its translational motion (TM) stops North of BI; (2) the vortex passes through the corridor between the LAA and the BI by reducing its size; and (3) The vortex stopped at the entrance to the corridor South of the BI. Isolated vortices were prone to stopped North of the BI. Apparently the intensity in the outer vorticity ring has an influence on the fate of the NBC ring. Non-isolated vortices can also stop its TM North of the BI because when in \(\beta\) plane they develop an outer ring similar to the isolated vortices. From these results we conclude that intense and big NBC rings are likely to stop its TM North of the BI. Medium and moderate vortices stops its TM South of the BI and they reduce their size until they are able to pass through the corridor between the LAA and the BI. Mild vortices of all sizes stop South of the corridor, close to the BI and the LAA. Drifter trajectories and Sea Surface Height altimetry confirm the results.  相似文献   
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Modelling nitrogen transfer and transformation at the landscape scale is relevant to estimate the mobility of the reactive forms of nitrogen (Nr) and the associated threats to the environment. Here we describe the development of a spatially and temporally explicit model to integrate Nr transfer and transformation at the landscape scale. The model couples four existing models, to simulate atmospheric, farm, agro-ecosystem and hydrological Nr fluxes and transformations within a landscape. Simulations were carried out on a theoretical landscape consisting of pig-crop farms interspersed with unmanaged ecosystems. Simulation results illustrated the effect of spatial interactions between landscape elements on Nr fluxes and losses to the environment. More than 10% of the total N2O emissions were due to indirect emissions. The nitrogen budgets and transformations of the unmanaged ecosystems varied considerably, depending on their location within the landscape. The model represents a new tool for assessing the effect of changes in landscape structure on Nr fluxes.  相似文献   
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The estimation of the sustainability performance of products requires tools to provide systematic approaches to the definition of impacts, indicators and comparative scenarios from early design stages. This paper illustrates the Relative Assessment of Indicators in Sustainability Enhancement (RAISE) methodology that is based on the measure of negative impacts generated during any product life cycle stage. This approach includes a systematic process for the definition and evaluation of indicators to compare the sustainability performance of products considering each indicator individually and using a holistic index of sustainability to entail an overall comparison between products from manufacturing scenarios. The RAISE method is developed with the aim of assessing sustainability performance of product life cycle stages and incorporating this assessment into the decision-making process when comparing different manufacturing scenarios. A guitar capo manufactured in polymeric material is used as case study to demonstrate the use of the method. In this paper, only the manufacturing stage is considered; however, the method can also be employed in other stages of the life cycle.  相似文献   
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The Sphere Project (consisting of both the Humanitarian Charter and Minimum Standards for Disaster Response) has made prominent contributions to the debates, thinking and work on the quality of assistance and accountability of aid agencies. However, since its inception in 1997, several agencies expressed concerns regarding Sphere's approach, many of which were confirmed by the Sphere evaluation (2002/3). The present article restates these concerns, and addresses more fundamental issues regarding Sphere's cornerstone. It questions the validity of Sphere's rights-based approach, which consists of a tenuous link between the rights of affected populations and standards for technical interventions. Sphere is founded on "the right to assistance", although this right does not exist in international law. Its elaboration would entail solving several complex legal and political issues, which Sphere fails to address. This article also questions the validity and usefulness of universal standards for technical performance in helping relief agencies provide adapted assistance to disaster-affected populations, in line with their mandates and principles. It suggests that Sphere's approach and content largely reflect the concerns, priorities and values of technical professionals in Northern agencies, leaving limited space to genuine "participation" by affected populations and partners from the South.  相似文献   
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The development of a comprehensive sustainability analysis tool for evaluating regional urban systems would present researchers, planners, and policy makers with a powerful tool to study and manage systems, with the goal of encouraging optimum social and economic trends, while maintaining long-term environmental protection that leads to sustainability. This article intends to aid in this effort by presenting a versatile methodology for assessing sustainability as a function of dynamic changes in significant characteristics of urban systems. Using statistical methods, this work presents a strategy for comparatively assessing the impact of social and economic characteristics on system stability at geographic scales which are critical to policy and management. Specifically, it employs the Fisher Information index as a measure of sustainability, in order to distinguish periods of stability. As an application of the approach, six Metropolitan Statistical Areas (MSAs) in Ohio (Cincinnati, Dayton, Cleveland, Akron, Columbus, and Toledo) were evaluated for a regional sustainability assessment. Results from the multiyear analysis suggest two distinct periods in these MSAs: one characterized by 30 years of socio-economic growth (1970–1999) and another (2000–2009) denoting a change in the trajectory of each system found to be related to economic recession. Columbus was identified as the most stable and sustainable of the MSAs during the study period. In contrast, Toledo exhibited the largest changes in economic trends, as distinguished by excessive increases in the growth rate of vacant housing units, unemployed civilian labor force, and inhabitants below the poverty level (2000–2009). Since such conditions are not desirable for urban systems, they are indicative of movement towards an unsustainable future.  相似文献   
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Electrochemical water treatment technologies are highly promising to achieve complete decolorization of dyebath effluents, as demonstrated by several studies reported in the literature. However, these works are focused on the treatment of one model pollutant and generalize the performances of the processes which are not transposable since they depend on the pollutant treated. Thus, in the present study, we evaluate, for the first time, the influence of different functional groups that modify the dye structure on the electrochemical process decolorization performance. The textile azo dyes Reactive Orange 16, Reactive Violet 4, Reactive Red 228, and Reactive Black 5 have been selected because they present the same molecular basis structure with different functional groups. The results demonstrate that the functional groups that reduce the nucleophilicity of the pollutant hinder the electrophilic attack of electrogenerated hydroxyl radical. Thereby, the overall decolorization efficiency is consequently reduced as well as the decolorization rate. Moreover, the presence of an additional chromophore azo bond in the molecule enhances the recalcitrant character of the azo dyes as pollutants. The formation of a larger and more stable conjugated π system increases the activation energy required for the electrophyilic attack of ?OH, affecting the performance of electrochemical technologies on effluent decolorization.  相似文献   
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A general theory known as the waste reduction (WAR) algorithm has been developed to describe the flow and the generation of potential environmental impact through a chemical process. The theory defines indexes that characterize the generation and the output of potential environmental impact from a process. The existing theory has been extended to include the potential environmental impact of the energy consumed in a chemical process. Energy will have both an environmental impact as well as an economic impact on process design and analysis. Including energy into the analysis of environmental impact is done by re-writing the system boundaries to include the power plant which supplies the energy being consumed by the process and incorporating the environmental effects of the power plant into the analysis. The effect of this addition on the original potential impact indexes will be discussed. An extensive engineering economic evaluation has been included in the process analysis which inherently contains the cost of the consumed energy as an operating cost. A case study is presented which includes a base process design and two modifications to the base design. Each design is analyzed from an economic perspective and an environmental impact perspective. The environmental impact analysis is partitioned into the impacts of the non-product streams and the impacts of the energy generation/consumption process. The comparisons of these analysis procedures illustrate the consequences for decision making in the design of environmentally friendly processes.  相似文献   
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