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281.
高原环境对航空保障装备的影响分析及对策   总被引:2,自引:0,他引:2  
高原地区独特的气候环境会对航空保障装备技术性能的正常发挥产生重要影响。根据高原气候环境特点和保障装备结构组成,从动力系统、电气系统、气源系统和液压系统四个方面,分析了高原环境对保障装备的影响因素,有针对性地提出了保障装备在高原环境下的改进对策,可为现役装备技术改进和新型装备设计研制提供理论参考。  相似文献   
282.
本文简要评析了国际经济与社会可持续发展中民间规制的现状,指出尽管国际民间规制对规范与提升国际经济行为发挥了十分积极的作用,一定程度上弥补了政府公共治理的局限,但无论是在国际上还是国内范围,它们都不足以成为经济发展进程中政府规制的替代品.  相似文献   
283.
Bushmeat hunting, a key source of dietary protein, has been implicated as a major extinction threat to tropical vertebrate species in West Africa. Ideally, any such hunting of wild species should be done sustainably, with off-take levels low enough to ensure viability of harvested species. Recent work purports to show that a mature bushmeat market in a major city in Ghana operates sustainably after depletion of vulnerable, slow-reproducing species (Cowlishaw and others 2005). I revisit two aspects of this work. First, I retest the prediction that larger species are transported to the market from greater distances, as expected if overexploitation depletes large species close to the city. Cowlishaw and others failed to find a significantly positive relationship between species-specific body mass and distance between capture site and the market. However, my reanalysis provides evidence for a positive relationship after all, consistent with unsustainable harvesting. In particular, ungulate species were harvested significantly farther from the market than smaller-bodied rodent species. Second, I caution that just because species “persist” in the marketplace in no way implies that they can withstand hunting pressure elsewhere and so should be of little concern to conservationists. I reveal that such species, despite their high intrinsic rates of population growth, are not robust elsewhere. Several of them have disappeared from a network of protected areas in Ghana (Brashares and others 2001). I show that faster-reproducing species are not necessarily more likely to persist in protected areas. The mere presence of fast-reproducing species in a mature bushmeat market should not be construed as generalizable robustness; criteria for ecological sustainability should ensure viability; and harvested species should be robust, not highly prone to extinction, in protected areas.  相似文献   
284.
Soil and water conservation (SWC) contests among farmer groups were organized in five rural villages in the Bolivian mountain valleys. The contests were aimed at quickly achieving widespread sustainable results. This article analyzes the effectiveness of these contests as an extension tool. Mixed results were obtained. In three villages, participation rates in the SWC activities introduced in the contests were still high even 2 years after project withdrawal. These were all villages where a solid foundation for sustainable development had been laid before the contests were held. Two years later, most families were still involved in maintenance of the SWC practices introduced in the contests, and many farmers had started to experiment with different soil management practices. However, replications of these SWC practices were not widespread, Conservation Leaders did not continue with their training activities, and the quality of maintenance of the practices was often not satisfactory. In order to become a more effective extension tool and achieve widespread impact, SWC contests must receive continued support by a catalyst agency. Moreover, other SWC contests should also be organized in which practices are not predefined. Given that SWC contests are a low-budget extension tool, local municipalities could become more actively involved.  相似文献   
285.
Spain's Programa AGUA was proposed in 2004 as a replacement for the Spanish National Hydrological Plan and represented a fundamental policy shift in national water management from large inter-basin water transfers to a commitment to desalination. Twenty-one desalination facilities are planned for six provinces on the Spanish Mediterranean coast to supplement their water needs. These include the province of Almería that for the last 30 years has endured a net water abstraction overdraft leading to serious reservoir depletion and groundwater imbalances. Rising water use is a result of increasing demand to support irrigated agriculture (e.g. greenhouse horticulture) and for domestic needs (e.g. rapid urban growth and tourism development), which has led observers to question Almería's long-term water sustainability. Desalinated water alone is unlikely to be sufficient to make up these water deficits and water-users will have to accept a move to full-price water recovery by 2010 under the European Union (EU) Water Framework Directive of which Spain is a signatory. Anticipated water efficiencies resulting from higher water tariffs, increasing water reuse and water infrastructure improvements (including inter-basin transfers), in conjunction with increasing use of desalinated water, are expected to address the province's current water overdraft. However, Almería will need to balance its planned initiatives against long-term estimates of projected agricultural and domestic development and the environmental consequences of adopting a desalination-supported water future.  相似文献   
286.
The paper explores the role of a participatory approach in the outcome of the Finnish sustainable development indicator (SDI) exercise in 1998-2002. The process is analysed through three main objectives: to achieve stronger democracy, better quality of the end product and a more effective process. The analysis is further structured by a set of criteria needed for successful participation and differentiation of types of participants. The criteria comprise three main aspects: fairness, competence and social learning. In addition to the normally mentioned stakeholders (e.g. citizens and interest groups) participants also include experts and civil servants. Using the set of criteria above the participatory approach of the Finnish SDI process is then evaluated, and in the light of this evaluation the paper also discusses the specifications needed as evaluation criteria for national level policy programme processes like developing the SDIs. The results are based on documentation of the indicator task force meetings, written comments and a study of the putative end-users conducted after the publication of the indicators. The results show that the intense and broad participation of experts and civil servants increased the competence of the outcome and led to greater efficiency in working methods. However, this led to technocratic participation, absence of democratic participation and absence of social learning. Thus the ultimate goal of SDIs to contribute to achieving sustainability was not reached.  相似文献   
287.
- DOI: http://dx.doi.org/10.1065/espr2006.02.294 Background, Aim and Scope. To better address the requirements of the changing multilateral order, the United Nations Industrial Development Organization (UNIDO) Cleaner Production Programme, in 2004, developed the new Sustainable Industrial Resource Management (SIRM) approach. This approach is in accordance with the principles decided at the United Nations Conference on Environment and Development (UNCED) in Rio de Janeiro, Brazil in 1992. Unlike the traditional approaches to environmental management, the SIRM concept captures the idea of achieving sustainable industrial development through the implementation of circular material and energy flows in the entire production chain and reduction of the amount of material and energy used with greater efficiency solutions. The SIRM approach seeks to develop new models to encourage a shift from selling products to supplying services, modifying, in this manner, the supplier/user relationship and resulting in a win-win situation for the economy and the environment. Chemical Leasing represents such a new service-oriented business model and is currently being promoted by UNIDO′s Cleaner Production Programme. Main Features. One of the potential approaches to address the problems related to ineffective use and over-consumption of chemicals is the development and implementation of Chemical Leasing business models. These provide concrete solutions to the effective management of chemicals and on the ways negative releases to the environment can be reduced. The Chemical Leasing approach is a strategy that addresses the obligations of the changing international chemicals policy by focusing on a more service-oriented strategy. Mexico is one of the countries that were selected for the implementation of UNIDO's demonstration project to promote Chemical Leasing models in the country. The target sector of this project is the chemical industry, which is expected to shift their traditional business concept towards a more service and value-added approach. This is being achieved through the development of company specific business models that implement the above-indicated Chemical Leasing concept with the support from the Mexican National Cleaner Production Centre (NCPC). Results and Conclusions. The implementation of Chemical Leasing in Mexico has proven to be an efficient instrument in enhancing sustainable chemical management and significantly reducing emissions in Mexico. Several companies from the chemical industrial sector implement or agreed to implement chemical leasing business models. Based on the positive findings of the project, several Mexican companies started to negotiate contents of possible Chemical Leasing contracts with suitable business partners. The project further aimed at disseminating information on Chemical Leasing. It successfully attracted globally operating companies in the chemicals sector to explore possibilities to implement Chemical Leasing business models in Mexico. At the international level, the results of the UNIDO project were presented on 20TH September 2005 during a side event of the Strategic Approach to International Chemicals Management (SAICM) Preparation Conference in Vienna. Recommendations and Outlook. To facilitate the promotion and application of Chemical Leasing project at international level, UNIDO is currently developing a number of tools to standardize Chemical Leasing projects. These include, among others, Chemical leasing contract models; Chemical Leasing data base to find partners for chemical leasing; and guidelines to implement Chemical Leasing projects and work programmes.  相似文献   
288.
The recently-adopted global Sustainable Development Goals (SDGs) will have significant implications for national development planning in both developed and developing countries in the post-2015 period to 2030. Integrated, nationally-owned SDG strategies will be at the centre of national efforts to implement the new sustainable development agenda. The long-run processes and systems perspective that are inherent in the SDGs present complex analytical problems for policymakers and analysts. Scenario analysis and quantitative modelling will be important analytical tools to support national sustainable development planning, and there is an increasingly sophisticated suite of models available to decision makers. This paper reviews and assesses a broad range of different quantitative models that have the potential to support national development planning for the SDGs. The study develops a typology and inventory of 80 different models, and then reviews the comparative strengths, weaknesses and general utility of different models through an initial screening and subsequent multi-criteria analysis of short-listed models. Current gaps in model capabilities are highlighted in the context of providing analytical support for national development planning for the SDGs. While some existing models are particularly relevant, it is unlikely that an ideal model can analyse all SDG targets and variables of interest within a single modelling framework. Top-down ‘macro framework’ models are likely to be more useful for undertaking system-level or economy-wide scenario analysis driven by the national long-term goals and targets, and for exploring trade-offs and synergies among sectors. Bottom-up sectoral models will be able to support far more detailed option-level impact analysis of concrete interventions, technologies and investments. Combining both approaches within an analytical framework will provide a robust approach for analysis and decision-making. The results highlight a range of potential gaps in current modelling capabilities, and provide some new tools to assist with model selection.  相似文献   
289.
Stakeholder participation is considered a key principle for sustainable development in the context of natural resource and disaster risk management. Participatory modelling (PM) is an interactive and iterative process in which stakeholder involvement is supported by modelling and communication tools. Planning and decision-making for sustainable development (SD)integrate three substantive dimensions − social, ecological and economic. The procedural dimension of SD, however, is equally important, and here we see great potential for PM. In this study, we evaluate five PM research projects against criteria for the procedural dimension of SD. This provides a basis for identifying key issues and needs for further research into PM for SD. While the cases show great potential, especially for supporting knowledge integration, learning and transparent handling of values and perspectives, they indicate a particular need to develop PM in respect of organizational integration. This issue is closely connected to the possibility of effectively implementing PM in practice.  相似文献   
290.
In Bolivia, recent decentralisation policies have broadened the participation of local actors in development processes. However, development is far from sustainable, and poverty and natural resources degradation still increase. The challenge is to develop strategies that achieve the genuine participation of poor farmers in natural resources management and sustainable development. The logical strategy, which was developed and validated in five Bolivian mountain villages, is an example. In this strategy, first a solid foundation for sustainable development is laid, with activities focussing on five basic conditions for sustainable development in rural villages: leadership and organisation, responsible participation, effective collaboration, mutual trust and environmental awareness. The results show that the existence of a solid foundation is crucial for the success of other development activities, such as soil and water conservation activities. However, given that 2 years after the project’s withdrawal the firmness of the foundation had slightly weakened, it was concluded that a better integration of these villages in local development processes is essential to profit from the new dynamics. This is especially true for soil and water conservation. To achieve this integration, municipalities—with the support of international development agencies—must be encouraged to invest in laying this solid foundation in rural villages and in facilitating follow-up activities to keep the dynamic process going. This study shows that such investments result in better organised villages, more equality, and the genuine participation of more people in sustainable village development. Effective collaboration and accountability at institutional level are, however, required.  相似文献   
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