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111.
以滇池流域为例,介绍一种利用概化网络进行水资源调控仿真与预测的思路与方法,为流域水资源的宏观调控与管理规划提供决策支持。  相似文献   
112.
分析锻造企业生产的信息流和物流的规律,建立了相应的数据库,并介绍了锻造企业计算机信息管理MIS系统的开发步骤、原则、功能及主要特色。  相似文献   
113.
GIS在城市垃圾收运规划研究中的应用   总被引:5,自引:0,他引:5  
王羽 《环境科技》2002,15(2):28-30
根据国内外对垃圾收运规划的研究现状,叙述了应用GIS于垃圾收运规划,将GIS与收运模型有机结合是实现对城市垃圾收运系统进行信息管理的基础和关键。介绍GIS在垃圾收运规划研究中的应用,最后以分类收运系统规划为例说明应用GIS进行研究的基础性意义。  相似文献   
114.
This paper assesses the Bluff oyster fishery in New Zealand as a case study in common pool resource management. It discusses ways in which modern information technology, augmented by low-tech data gathering strategies and community ethnography, can be used to produce an integrated scientific and local knowledge-inspired fishery database that lends itself to fostering collaboration in resource management and planning. The specific context and state of the oyster fishery in Bluff are described. Issues regarding undocumented and ephemeral intergenerational knowledge, much of which is geospatial in nature, on the fishery, the current crisis that many see in the future of the fishery, and a lack of cohesion or common sense of purpose between the stakeholder groups are discussed. It is argued that the digital resource that results from the integration of local and scientific knowledge and the potential community building processes that can ensue from collaboration and dialogue around this centrepiece are of central importance in developing an oyster fishery management plan that is holistic in concept and sustainable in purpose.  相似文献   
115.
The dual goals of the Organic Act of 1916 and Wilderness Act of 1964 are to protect natural resources and provide quality visitor experiences. Park managers need metrics of trail conditions to protect park resources and quality of visitor experiences. A few methods of sampling design for trails have been developed. Here, we describe a relatively new method, spatially balanced sampling, and compare it to systematic sampling. We evaluated the efficiency of sampling designs to measure recreation-related impacts in Rocky Mountain National Park. This study addressed two objectives: first, it compared estimates of trail conditions from data collected from systematic versus spatially balanced sampling data; second, it examined the relationship between sampling precision and sampling efficiency. No statistically significant differences in trail condition were found between the 100-m interval and the spatially balanced datasets. The spatially balanced probability-based dataset was found to be a good estimate of trail conditions when analyses were conducted with fewer sample points. Moreover, spatially balanced probability-based sampling is flexible and allows additional sample points to be added to a sample.  相似文献   
116.
促进贫困地区农村劳动力向外流动是提高农民收入、缩小城乡差距的关键。在农村劳动力尤其是贫困劳动力外流增速放缓的背景下,文章从信贷约束缓解的视角出发,基于5省10县互助资金监测的准实验研究项目,借助双重差分(DID)模型,利用1059个微观农户的三期面板数据,从家庭层面考察了互助资金政策对贫困村劳动力流动的影响,并从缓解流动性约束、资本替代劳动和提供隐性担保三个角度对作用机制进行了分析和检验。研究结果表明:①互助资金政策的实施对贫困村劳动力外流具有显著的促进作用。安慰剂检验和稳健性检验进一步加强了研究结论的可靠性。②缓解农户的流动性约束是互助资金促进贫困村劳动力外流的路径之一,通过向农户提供借款,使农户尤其是贫困农户获得了满足迁移成本的金融资源,从而促进了向外流动。③资本替代劳动的机制作用并不明显,这可能与互助资金借款额度有限有关,无法满足农户机械化的资本需求。④为农户家庭面临的收入风险提供隐性担保也是互助资金促进贫困村劳动力外流的路径之一,通过为农户提供资金融通渠道,确保农户即使在外流失败的情况下能够通过向互助资金借贷平滑消费和缓解风险冲击。研究结论为探索农村金融供给能否成为进一步促进剩余贫困劳动力转移的契机提供了有理论价值和可操作的视角,未来应继续坚持农村金融改革的步伐,加快金融产品和金融工具创新,不断提高贫困农户的信贷可得性和可持续性收益。  相似文献   
117.
It is generally accepted as a useful and workable hypothesis that when an ecosystem receives an inflow of exergy (energy that can do work) it will utilize this flow of exergy to move as far away from thermodynamic equilibrium as possible after the exergy (energy) for maintenance has been covered. If more combinations of system components including organisms are offered, the combination of components and processes that will bring the system most away from thermodynamic equilibrium will win.The amino acid sequences of the proteins e.g. enzymes determine and control the life processes of the organisms and may be viewed as information sensu lato. The free energy of oxidation of the amino acids and the peptide bonds of the cell enzymes expresses therefore the exergy content, eco-exergy or work capacity that the information contributes to “moving further away from thermodynamic equilibrium”. In this paper eco-exergy is calculated and plotted versus the β-values (a measure of the information contained in the genome) for different organisms. The eco-exergy density was previously (see [J?rgensen et al., 1995] and [J?rgensen et al., 2005]) proposed to be calculated as the summation of the product of the β-values representing the information of the genome multiplied by the concentrations of the respective ecosystem components. This analysis shows a strong correlation between the β-values and free energy released when oxidizing the enzymes. The β-values can therefore be assumed to represent the free energy that the organisms have invested in genetic information.  相似文献   
118.
阐述了排污申报登记与环境监理的关系。指出,排污申报的作用 应当体现在对污染源监理的全过程中,应对申报数据进行核查,形成一个有效的污染源动态管理系统,并建立相应的污染源动态信息库。  相似文献   
119.
To reveal the mechanism of information loss in the flow of safety information, and to derive an evaluation method for describing this information loss, this paper analyzes the flow of safety information based on research in safety informatics and cognitive psychology. Theoretical analysis shows that the flow of safety information can be divided into four stages: transformation, transmission, perception, and cognition. This paper describes a simplified model of the flow of safety information based on these four stages. Then, the concept of adaptive subjects is introduced, and the sources and losses of safety information are explored. In addition, a model of safety information flow loss is constructed. This model is used to analyze the connection between the information loss at each stage of the sharing process, and then a “ladder hierarchical” model for the loss of safety information is developed. Comprehensive analysis of this ladder hierarchical model of safety information leads to a formal mathematical model of safety information loss. Finally, according to the various development stages of the safety information sharing process, four key factors that affect the multilevel information loss of the safety information sharing process are extracted by the hierarchical method.  相似文献   
120.
分析了我国污染地块环境管理的现状,以及当前存在的法律法规和标准不健全、备案制还是信息公开的不确定、修复行业亟须引导规范等问题,提出了做好顶层设计、完善标准规范体系、加强对从业单位的管理等对策建议。  相似文献   
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