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21.
Tone River supplies most of the water requirements of the Tokyo Metropolitan Area (TMA). Lowering of Tone flow and yearly fluctuation, however, is causing water shortage along TMA nowadays. This study investigated the future water availability scenarios under climatic changes. A state-of-the-art approach to utilize the output of several GCM has been demonstrated to investigate the future water availability scenarios for TMA from the Tone River. An integrated modeling approach for water balance considering several hydrological risk indices was adopted to quantify the future changes in this case. It is observed that the future summer precipitation along the Tone basin is going to be increased considerably, while an almost constant or decreasing trend is observed for winter season. Natural flow availability for winter or spring seasons thus can be crucial under future scenarios. After reservoir routing, the hydrological risk indices estimated, however, were not found to be changed significantly due to the presence of a robust reservoir system at the upstream.  相似文献   
22.
The implementation of sustainable development may seem a simple concept when written on paper. However to carry-out long term actions put forward by the Agenda 21 (AG21) at the local level represents one of the main challenges as municipal governments in general do not have the capacity to effectively implement the process. Regional environmental assessment (REA) has shown to be effective in supporting decision-making not only to correct environmental problems due to past unsustainable social-economic developments but also help local governments to implement sustainable actions. However this requires long-term investments of AG21 plans and projects. The allocation of regular and consistent financial resources is one of the main ingredients for the sustainable development process. But traditional plans and projects financed by national and/or international funds may not be sustainable in the long-term because they become dependent on external funding. Research demonstrate that innovative economic instruments such as ecotaxes represent a feasible alternative to sponsor local sustainability because taxes are collected permanently by the government and could be invested in continuous actions. Ecotaxes experiences have provided important reference to structure a municipal incentive model (MIM) to sponsor AG21’s environmental plans and projects on a long-term (permanent) basis. However sustainable development cannot be solely through economic investments. A comprehensive municipal environmental management scheme (MEMS) has been established to support the incentive model. The scheme seeks not only to improve local institutional framework but also incentive continuous participation of local stakeholders at all levels of society. Participatory events and the provision of incentives (educational and financial) are key to motivate society to protect the environment and support actively the sustainable development process as emphasised in the RIO-92 Conference.  相似文献   
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选择5台国六直喷汽油车采用3种不同组分的E10乙醇汽油和1种不含含氧化合物的国VI汽油,按照国六排放标准开展了WLTC循环测试,研究乙醇和基础油组分对污染物排放的影响规律.结果表明,多数国六直喷汽油车的CO、THC和PM排放有所降低,NOx排放无明显差异,PN排放微增,所有样车的CO、THC和PM平均排放降低为6%、7%和14%.E10乙醇汽油中的重质芳香烃含量增高时,PN排放明显增加,PN排放与PMI指数呈现较强的正相关关系.  相似文献   
26.
A case study to identify major factors for lubricant mist exposure covered 15 metal machining sites. The investigation included milling, turning, drilling and grinding applications. Systematic analysis considered all relevant data concerning the machine tool, the lubricant and the suction plant. The efficiency of the implemented maintenance program at the installed filter systems was checked by concentration measurements immediately before and after service. All performed measurements of lubricant aerosol and vapor loads upstream and downstream of the installed filter systems were carried out according to VDI 2066 and BIA 3110, respectively. The selection criteria for the sites to be investigated, the systematic nature of the data acquisition and the procedure of the analysis are demonstrated in detail by performing comparisons between selected applications using emulsions and those employing straight oil for lubrication. The results of the study identify recirculation of ventilated air as the major source of workplace exposure to airborne lubricant emissions. More than 60% of the demisters investigated emit air at total lubricant loads (aerosols and vapor) above the limit of 20 mg m-3 at any time of operation; which also means immediately after service. A common reason for exceeded aerosol loads in recirculated air is e.g. the fact that the type of filter system applied is often not suitable for the separation problem. Loads of lubricant vapor are usually higher at the processes which use water emulsions as lubricant. In a quarter of the cases the limits were exceeded solely due to high vapor loads even immediately after service. The exposure can be reduced by replacing the lubricant, installation of a vapor separation plant or avoiding air recirculation. Maintenance time of the demisting system and aerosol separation efficiency of state-of-the-art demisting systems can be expanded by implementation of enhanced preliminary filter stages. This study confirms that appropriate service measures lower both aerosol emissions and lubricant vapor concentrations due to the reduction of exposed oil-wetted surfaces. The performed measurements show no significant relationship between loads of airborne lubricants and the type of machining process. Therefore, investigations at a much more detailed level have to be performed. However, the individual assessment of any workplace due to the complex situation remains essential.  相似文献   
27.
Recently, the New Morris Method has been presented as an effective sensitivity analysis tool for mathematical models. The New Morris Method estimates the sensitivity of an output parameter to a given set of input parameters (first-order effects) and the extent these parameters interact with each other (second-order effects). This method requires the specification of two parameters (runs and resolution) that control the sampling of the output parameter to determine its sensitivity to various inputs. The criteria for these parameters have been set on the analysis of a well-behaved analytical function (see Cropp and Braddock, Reliab. Eng. Syst. Saf. 78:77–83, 2002), which may not be applicable to other physical models that describe complex processes. This paper will investigate the appropriateness of the criteria from (Cropp and Braddock, 2002) and hence the effectiveness of the New Morris Method to determine the sensitivity behaviour of two hydrologic models: the Soil Erosion and Deposition System and Griffith University Representation of Urban Hydrology. In the first case, this paper will separately analyse the sensitivity of an output parameter on a set of input parameters (first- and second-order effects) for each model and discuss the physical meaning of these sensitivities. This will be followed by an investigation into the sampling criteria by exploring the convergence of the sensitivity behaviour for each model as the sampling of the parameter space is increased. By comparing these trends to the convergence behaviour from Cropp and Braddock (2002), we will determine how well the New Morris Method estimates the sensitivity for each model and whether the sampling criteria are appropriate for these models. It will be shown that the New Morris Method can provide additional insight into the functioning of these models, and that, under a different metric, the sensitivity behaviour of these models does converge confirming the sampling criteria set by Cropp and Braddock.  相似文献   
28.
Conclusion  In this paper we have considered a specific environmental game emphasizing both control-prevention efforts and the propensity to pollute by a firm which adopts a given pollution abatement technology. A random payoff game was constructed and solved under a risk neutral assumption and quadratic utilities for both the firm and the environmental controller. The game thus defined, provides a wide range of interpretations and potential approaches for selecting a control-inspection policies to prevent environmental risks. There are of course many facets to this problem, which could be considered and have not been considered in sufficient depth. For example, more complex control mechanisms and liabilities, the effects of insurance and risk sharing, the application of cooperative efforts and subvention of pollution abatement investments (through tax incentives and their like), etc. have not been considered [5,7]. These are topics for further research. The basic presumption of this paper is that it is very difficult to fully enforce pollution prevention by firms, as a result, some controls are needed to ensure that firms be controlled so that appropriate efforts are carried.  相似文献   
29.
The complexity of today’s research problems increasingly demands that scientists move beyond the confines of their own discipline. In this special issue, the basics of a transdisciplinary framework are established and problems analyzed in a specific discipline are successfully integrated in this transdisciplinary network. The intent has been to go beyond only statements about the importance of enabling early stage researchers to work across disciplinary boundaries, and to show that important discoveries are being made at the intersection of disciplines. Embedding various research projects in a more global framework can meet the demands of an interdisciplinary or transdisciplinary approach (especially for early stage researchers) and contribute significantly to sustainable research.  相似文献   
30.
A study on the orbit of air temperature movement   总被引:1,自引:0,他引:1  
In this paper, we describe an air temperature movement by mapping its time series to the polar coordinates: the value of the time series is plotted on the radial coordinate and the time on the angular coordinate. In this way, both the yearly and daily air temperature movements from five different locations of China are used to demonstrate that, in an intuitionistic view, air temperature movement is neither random nor chaotic, but has its own orbit. We then propose an elliptic orbit model for the air temperature movement. Our proposed model provides quite good results when it is applied to the evaluation of yearly air temperature movements in eight locations in various parts of the world, and the evaluation of daily air temperature movements in five locations in Hunan Province of China on December 17, 2005. Results show that our approach provides a concise and helpful model for air temperature analysis.  相似文献   
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