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261.
In a world of persistent and growing informality of working and living conditions in cities, and increasing policy efforts to formalise the informal, why are some forms of informality criminalized while others enjoy sanction of the state? This paper argues that analysis of the politics of policy implementation of formalisation efforts can provide rich insights into urban formal-informal relations in cities of the global south, to complement policymaking or policy impact analyses. We present an in-depth case study analysis of the contested implementation of a unique policy effort to formalise street vendors in Delhi, India. A public authority lens reveals the micro-political practices employed by non-state and state actors in bureaucratic, judicial, political, market and other arenas aiming to control urban space. We argue that policy implementation outcomes are significantly shaped by ‘horizontal' contestations within society and within the state, to complement and intermesh with ‘vertical' state-society struggles. Moreover, contestants for public authority exploit official rules but also informal practices by the state, to engage and advance state fragmentation, enduringly shape cityscapes and to affect which forms of informality are condoned or condemned.  相似文献   
262.
New multi-sectoral policies with a regional implementation are developed when maritime states recognise the importance of managing the marine environment under an ecosystem-perspective rather than a use-perspective. In Europe, the Marine Strategy Framework Directive (MSFD) is the first attempt to promote an integrated management of the seas from the coastline to the limit of the Exclusive Economic Zone. This paper shows that, nine years from the MSFD adoption, there remain several ecological, economic, social and governance challenges. Using information gathered in a dedicated survey of the European Union Marine Strategy Coordination Group and in the recent literature the paper identifies the obstacles preventing a successful regional cooperation and policy integration. The survey indicates that the MSFD coordination structures are, in general, well-developed but there is an apparent lack of political will to coordinate actions at the regional level. Member States request greater flexibility to implement the Directive but they put their national interests before the benefit of a coherent and integrated approach for the entire region. Differences in budget, economic sector predominance, lack of staff and the MSFD short time-scale are identified as the factors that can hamper cooperation. These have produced recommendations of possible strategies for optimising regional coordination structures which respect the subsidiarity principle underpinning the MSFD.  相似文献   
263.
Notwithstanding a complex array of international, national, and local policies designed to protect biodiversity and manage human activities, the condition of Australia's Great Barrier Reef has been deteriorating. This trend indicates that policy settings are inadequate or the right policies have been prescribed but not effectively implemented. This study aimed to determine which policies influenced on-ground management of the Great Barrier Reef World Heritage Area and Marine Park, how they were implemented, and the challenges encountered by practitioners in applying policies. The research required content analysis of policy instruments relevant to various jurisdictional levels, and surveys and interviews with 19 key informants across jurisdictions and agencies. This study found that policy intent is not automatically translated into practice: international agreements are interpreted and reinterpreted along the policy pathway to on-ground management and, consequently, the aspirations of these agreements can be frustrated and their effectiveness diluted. Due to limits of jurisdictional responsibility, practitioners within the Great Barrier Reef Marine Park Authority are constrained in influencing key factors that impact on their capacity to address threats and manage outcomes. The major policy gap affecting management outcomes was the absence of a mechanism with which to manage cumulative impacts responsible for deterioration of key ecosystem processes and biodiversity. These findings highlight that effective policy implementation is a challenging task, limited by gaps between intentions and outcomes, inconsistencies, and conflicting agendas. An improved understanding of the policy implementation process and the policy-practitioner relationship is essential to enhancing links between policy and on-ground management.  相似文献   
264.
Particulate matter (PM) emissions from ships in ports are a major contributor to air pollution and smog in port cities. The issue of how to reduce PM emissions has become a critical concern for port city residents and governments. This paper establishes an incentive policy to reduce PM emissions from ships in ports. Using a Panamax bulk carrier as a case study, eight alternative approaches that could be adopted by shipping companies are compared and their operational benefits are estimated. By restricting the analysis to emission control areas (ECAs), the net present value (NPV) model shows that the diesel particulate filter (DPF) is the most advantageous approach with the highest NPV, while the exhaust gas scrubber (EGS) approach is the most economically inefficient. Meanwhile, due to DPF's excellent performance in PM abatement, it is suggested that governments should prioritize the DPF approach when promoting the application of emission reduction technologies. From the perspective of social welfare, a positive social benefit of about US $20,000 will be generated over the life cycle of a ship. However, a low government pricing in China will reduce shipping companies’ operational performance as the emission control zone (ECZ) gradually expands. As a result, an appropriate subsidy scheme is necessary to encourage shipping companies to apply emission reduction technologies.  相似文献   
265.
Application of multiple hybrid underwater gliders (HUGs) is a promising method for large scale, long-term ocean survey. Attitude coordination has become a requisite for task execution of multi-HUG formation. In this paper, a multibody model is presented for attitude coordination among agents in the HUG formation. The HUG formation is regarded as a multi-rigid body system. The interaction between agents in the formation is described by artificial potential field (APF) approach. Attitude control torque is composed of a conservative torque generated by orientation potential field and a dissipative term related with angular velocity. Dynamic modeling of the multibody system is presented to analyze the dynamic process of the HUG formation. Numerical calculation is carried out to simulate attitude synchronization with two kinds of formation topologies. Results show that attitude synchronization can be fulfilled based on the multibody method described in this paper. It is also indicated that different topologies affect attitude control quality with respect to energy consumption and adjusting time. Low level topology should be adopted during formation control scheme design to achieve a better control effect.  相似文献   
266.
新型城镇化是以人为核心的城镇化,山东半岛城市群作为我国11个国家级城市群之一,近年来城镇化发展速度不断加快。以山东半岛城市群8个设区城市为研究对象,通过构建城市土地扩张与人口增长协调关系模型,计算8个城市的土地扩张与人口增长协调度,并根据城市土地扩张与人口增长的协调性分级标准,把1994年和2013年8个城市的土地扩张与人口增长协调性关系进行分等定级评价。结果表明:山东半岛城市群城市土地扩张与人口增长的协调性较弱,呈现出土地快速扩张态势。8个城市中有5个城市表现为土地快速扩张,其中2个城市表现为土地显著扩张,3个城市表现为土地明显扩张;人地基本协调的仅有3个,协调性空间分异明显。针对8个城市土地扩张与人口增长间不同类型的协调度,提出发展建议,促进山东半岛城市群城市土地扩张与人口增长协调发展,提高城镇化发展质量。  相似文献   
267.
通过对山东半岛城市群地区地质生态环境与经济发展要素分析,构建了两者协调性评价的指标体系;在此基础上,根据协调性测度算法原理,对"十五"期间山东半岛城市群地区地质生态环境与经济发展协调度及其协调发展状态进行了分析评价。结论是为了实现山东半岛城市群地区地质生态环境与经济之间的协调、持续发展,应合理调整两者之间的互动关系。  相似文献   
268.
通过电位滴定研究了从洞庭湖沉积物中分离得到的腐殖酸(HA)的酸碱性和配位性,采用修正格兰函数进行了数据拟合。表征了六类可滴官能团含量和分布,pKa数值在2.35~10.50之间,羧基占可电离中心总数的62%,利用铜离子选择电极和汞齐电极(Pb、Cd和Zn)研究了腐殖酸与Cu^2+、Pb^2+、Cd^2+和Zn^2+配位性质,借助Scatchard方法对数据进行了处理,显示铜和铅为二配体,镉和锌为单配体。平均稳定常数顺序为:logKHA-Pb〉logKHA-Cd〉logKHAtZn,配位能力顺序为:Pb〉Cu〉Cd≈Zn。  相似文献   
269.
陕北农牧交错区生态环境与经济协调发展评价   总被引:1,自引:1,他引:0  
生态建设与经济协调发展是可持续发展的基本要求.陕北地区属于典型的北方农牧交错地带,其生态与经济协调发展关系到国家能源安全,区域生态稳定,以及当地人民脱贫致富等诸多问题.运用主成分分析法、协调度和协调发展度对陕北农牧交错区生态环境与经济发展相互作用程度进行了定量评价.结果表明:1994-2005年陕北农牧交错区生态环境与经济协调度基本保持在良好协调类型,呈现稳定的态势.协调发展度评价结果显示,1996年以前,该区域发展主要受经济滞后制约;1997-2003年表现为生态与经济同步协调状态;2004年以后,主要表现为生态滞后影响区域社会经济发展.  相似文献   
270.
欧阳玲 《中国沙漠》2011,31(5):1278-1285
根据农户调查数据,运用人地关系协调度评价指标体系,定量评价了母子山村人地关系的协调程度。结果表明,母子山村人地关系系统的发展水平、发展效率、发展潜力、社会经济协调度、发展控制度5大功能团指数分别为0.34、0.52、0.57、0.53、0.54,人地关系协调度综合评价指数为0.48,人地关系处于基本不协调状态。从经济发展、文化、产业结构、人口与政府控制力等方面探讨了人地关系协调度的主要影响因素,指出教育先行、优化农业结构是优化调控村域人地关系协调度的重要途径。  相似文献   
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