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151.
以2011年间的数据对云南面向全国的地缘经济现状进行分析,结合新经济地理学中“核心—外围”模型,认为云南地缘空间关系处于多重“核心—外围”结构中.运用新经济地理学理论对滇中城市群空间经济演化和内生机制进行理论研究,为今后云南地区发展提供新理论支撑.  相似文献   
152.
文章通过对双积分政策下汽车制造商的产量博弈均衡进行建模分析,研究了双积分政策对企业层面异质制造商的产量决策和利润的影响,以及对产业层面新能源汽车和燃油汽车总产量及总产值的影响。研究结果表明:(1)新能源汽车产业向均衡演进过程中,新能源汽车制造商仍具有一定的发展潜力,但未来发展的中坚力量依靠优势燃油汽车制造商,劣势燃油汽车制造商可能会通过提高燃油经济性发展为优势燃油汽车制造商,从而提高优势燃油汽车制造商的燃油汽车总产量,降低劣势燃油汽车制造商的燃油汽车总产量。(2)双积分政策参数对异质制造商产量决策和利润的影响不同:新能源汽车制造商能够从中受益,而劣势燃油汽车制造商面临危机,转危为安的可能方式包括降低平均燃料消耗量和积极探索新能源汽车生产的可能性。对于优势燃油汽车制造商来说,双积分政策的收紧可能导致其转向燃油汽车市场,规制NEV积分价格上限有利于引导优势燃油汽车制造商转向新能源汽车市场。(3)促进新能源汽车规模增长的参数,可能导致总产值下降,政策调整应将规模增长和产值增长作为双目标,避免单一目标可能导致的市场波动。(4)随着双积分政策的收紧,可预见的新能源汽车积分比例要求提高以及平均燃料消耗量标准趋严,将刺激新能源汽车积分需求提升,缓解新能源汽车积分供需失衡问题。考虑到目前NEV积分价格处于低位,合理降低新能源乘用车车型积分有助于限制NEV积分供给。  相似文献   
153.
魏夕凯  马本 《中国环境科学》2022,42(8):3822-3831
充分考虑农村"熟人社会"特点,首次采用复杂网络演化博弈模型,通过数值仿真分析了声誉损失和奖励政策对农户垃圾分类行为扩散深度的动态影响.结果表明:政府不干预时,垃圾分类将无法在农村自发持续而普遍推广;在一定范围内提高声誉损失或奖励均可显著促进农户分类;仅依靠单一政策,无法实现分类的深度扩散,若依靠声誉损失与奖励相互配合,可实现低政策强度、高扩散深度的合意效果;搭便车收益的提高会抑制垃圾分类扩散深度;注重经验学习和适应能力的EWA学习策略更有助于促进垃圾分类扩散.上述结论广泛适用于分类初始状态、学习能力、人口规模不同的农村,对中国农村垃圾分类具有普遍性的启发意义.最后,提出了充分利用"熟人社会"优势构建与农村社会经济特征相契合的垃圾分类激励政策建议.  相似文献   
154.
Natural resource governance is by nature multi-level, mobilizing various multi-stakeholder arenas in which a social learning approach may play a role. An approach using simulation tools such as role-playing games was tested in metropolitan areas of two South American cities: (1) in the periphery of Cochabamba, to facilitate conflict resolution stemming from the impact of urbanization on the irrigation infrastructure, and (2) in peri-urban areas of São Paulo, to assist in negotiations on land and water management in a protected catchment. Both interventions were designed to broaden the stakeholders' perspectives and facilitate the exchange of the views of different actors on water and land management using role-playing games. This paper discusses how the scale strategy embedded in the tools and in the mode of participation in fact constrained the possibility of bridging the gap between organisational levels in both situations. This calls for both the crafting of multi-level approaches able to take different levels into account, and finding adequate bridging mechanisms to enhance the integration of learning within organisations and communities.  相似文献   
155.
Sulfonamides (SAs) are one class of the most widely used antibiotics around the world. Their fate and transport in the aquatic environment is of great concern. In this study, adsorption of four SAs—sulfadiazine (SD), sulfamethoxazole (SMZ), sulfadimethoxine (SDM) and sulfamethazine (SM2)—in single-solute and multi-solute systems on sediments of Dianchi (DC) Lake and Taihu (TH) Lake, China was investigated with batch experiments. In the single-solute adsorption system, the Langmuir model and the dual-mode model described the adsorption process better than the Freundlich model. Model fitness was better on DC sediment than on TH sediment. The order of adsorption capacity approximately followed a decreasing order of SDM>SD>SM2>SMZ on both sediments, which was likely attributed to the distinctly different water solubility of the four SAs. In the multi-solute system, the order of adsorption capacity was SM2>SDM>SD>SMZ, which was probably related to the compound speciation caused by the pH values of the experimental solution. In the multi-solute system, both competitive and cooperative adsorption played important roles in the adsorption of sulfonamides on sediments.  相似文献   
156.
李鹏  张俊飚  单海军 《生态环境》2012,(6):1178-1183
随着农业集约化、规模化发展,农业生产废弃物的管理问题凸显。循环农业、低碳农业的发展,在一定程度上激励了农户对农业生产废弃物资源化管理,取得了一定的成绩,但是也存在一定的问题,严重制约了农业生产废弃物资源化管理。文章通过构建政府与农户的动态博弈模型,分析补贴政策对农户提高农业生产废弃物资源化管理效率的作用,并基于政府与农户的动态博弈分析提出了促进农业生产废弃物管理效率提升及其可持续发展的建议,即:(1)根据不同的资源化管理方式的差异制定并实施差别补贴政策;(2)实行区域差别补贴标准;(3)延长补贴期限,实行分年度对农户进行不同数量的补贴;(4)培养农户管理意识,加强农户技能培训。  相似文献   
157.
李莎莎    崔铁军      马云东 《中国安全生产科学技术》2015,11(10):156-161
为了研究多专家对多方案的比选排序规则及数据特点,提出一种基于合作博弈-云化AHP算法处理该问题,并用以地铁隧道施工方案选择。方案选择对于控制施工成本,保证施工安全尤为重要。使用云模型嵌入AHP构建云化AHP模型对专家提供的不确定信息进行处理,得到在考虑实际工程背景下的方案偏好排序。使用合作博弈模型得到多个方案排序的综合排序。根据方案权重最大原则确定最优方案。分析了3位专家对3种隧道施工方案的偏好排序,其结果表明:对于给定的工程背景,盾构法施工是最优的。与现有4种模型进行对比,说明了其能更好地处理数据的不确定性,综合专家决策群意见,且数据量和计算量较小。  相似文献   
158.
为建立科学、合理的化工园区应急避难点,通过对园区企业、园区空间布局等方面调研分析,从安全性、可达性、适宜性3个方面构建化工园区应急避难点选址评估指标体系;结合AHP和熵值法的组合赋权法,对指标权重进行赋权,并基于博弈论思想对权重实现差异最小化处理,计算出各指标贡献率;将模型应用于广东省某化工园区避难所的选址问题,并对该化工园区应急避难点选址进行综合评估,提出针对性的园区避难点选址措施。  相似文献   
159.
Government administered protected areas (PAs) have dominated conservation strategies, discourse, and research, yet private actors are increasingly managing land for conservation. Little is known about the social and environmental outcomes of these privately protected areas (PPAs). We searched the global literature in English on PPAs and their environmental and social outcomes and identified 412 articles suitable for inclusion. Research on PPAs was geographically skewed; more studies occurred in the United States. Environmental outcomes of PPAs were mostly positive (89%), but social outcomes of PPAs were reported less (12% of all studies), and these outcomes were more mixed (65% positive). Private protected areas increased the number or extent of ecosystems, ecoregions, or species covered by PAs (representativeness) and PA network connectivity and effectively reduced deforestation and restored degraded lands. Few PPA owners reported negative social outcomes, experienced improved social capital, increased property value, or a reduction in taxes. Local communities benefited from increased employment, training, and community-wide development (e.g., building of schools), but they reported reduced social capital and no significant difference to household income. The causal mechanisms through which PPAs influence social and environmental outcomes remain unclear, as does how political, economic, and social contexts shape these mechanisms. Future research should widen the geographical scope and diversify the types of PPAs studied and focus on determining the casual mechanisms through which PPA outcomes occur in different contexts. We propose an assessment framework that could be adopted to facilitate this process.  相似文献   
160.
ABSTRACT: Access to clean and sufficient amounts of water is a critical problem in many countries. A watershed approach is vital in understanding pollution pathways affecting water resources and in developing participatory solutions. Such integration of information with participatory approaches can lead to more sustainable solutions than traditional “crisis‐to‐crisis” management approaches. This study aims at applying a watershed based joint action approach to manage water resources. Since most watersheds have urban and rural sources of pollution and a wide disparity in access to and use of water, alternative solutions need to take an integrated approach through cooperative actions. An institutional model was applied to seven subwatersheds in Honduras to evaluate various sources and effects of water contamination and water shortages. Two specific pathways of water resources degradation were studied (contamination from coffee pulp manufacturing and urban nonpoint sources) to develop alternative solutions that mitigate downstream impacts of access to clean water. A locally driven joint mechanism to reuse coffee pulp in farming systems is proposed. Such an institutional solution can maximize benefits to both farms and the coffee pulp industry. A combination of education and investment in sanitary facilities in urbanizing areas is proposed to minimize urban sources of water contamination.  相似文献   
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