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81.
82.
To achieve the desired outcomes of ecosystem-based or integrated coastal management, paradigm shifts must occur in all stages of the policy process. This article focuses on the evaluative stage following policy implementation, specifically on the use of coastal ecosystem condition indicators. A review of the recent literature suggests that coastal ecosystem condition indicators with too broad a scale or too narrow a scope lose utility and applicability. An analysis of these problems of scale and scope reveals that the process through which an index is designed and selected can hinder or heighten its validity. Local and diverse stakeholder input can help to ameliorate weaknesses, increasing the evaluative validity of coastal ecosystem condition indicators.  相似文献   
83.
This paper synthesizes evidence from the workshop on risk and reward in public transport contracting. It broadens the usual risk/reward framework to encompass strategic/tactical level issues, identifying high level community goals as the ultimate risk/reward pay-off. The evolution of tactical level public transport planning is reviewed, noting considerable change in functional roles between purchaser and provider in some jurisdictions. No single “best” approach is evident but an emerging interest in relational contracting founded on trust is apparent. Risk allocation between purchaser and provider is considered, a key debate concerning the extent to which providers should be exposed to revenue risk.  相似文献   
84.
重庆主城区浅层地温能适宜性分区评价   总被引:3,自引:0,他引:3  
基于综合评价理论建立了重庆主城区浅层地温能适宜性分区评价模型,确定了分区评价的指标因素及相应的权重值;利用综合指数法通过MAPGIS 6.7软件对研究区域内网格点进行分区总分计算,绘制了重庆主城区浅层地温能开发利用适宜性4级分区结果图.为浅层地温能在重庆主城区的合理开发利用提供参考.  相似文献   
85.
通过总结国际海事组织(IMO)船舶防污公约及国内外相关法律法规标准中关于船舶废弃物的排放要求和处理技术,针对海军舰船主要污染源油污水、生活污水、固体垃圾、废气排放、压载水的技术指标进行对比分析,论述了防污技术指标发展趋势,探讨了海军舰船防污技术指标的发展思路。  相似文献   
86.
行车准点率与RAMS可靠性的相关性   总被引:1,自引:1,他引:0       下载免费PDF全文
从服务表现指标与系统保证RAMS(可靠性、可用性、可维护性及安全性)的联系切入,采用由上而下分解法和由下而上验证法,论述表现轨道交通运营服务质量的宏观指标(行车准点率)与反映机电系统设备性能的微观指标(可靠性)之间的联系。以屏蔽门为例,定性并定量地论证行车准点率与可靠性之间的相关性,分析行车准点率与RAMS可靠性之间相互作用和相互依存的紧密关系,探索基于RAMS建立运营服务指标体系的理论和实践依据。  相似文献   
87.
The management success of a marine protected area (MPA) is essentially a social construct because people have differing views on what defines success. Conflicting opinions between stakeholders need to be identified and resolved to ensure these factors do not interfere with successful functioning of MPAs. This study looked at developing and prioritizing performance indicators for Maria Island Marine Nature Reserve (MIMNR), Australia. Performance indicators were developed for MIMNR based on an expert-led, structured framework and then prioritized using the Analytic Hierarchy Process (AHP), with respect to input from key informants of stakeholder groups. Results showed that all stakeholder groups agreed that management of MIMNR should first focus on “abundance and size of native species,” and that managers, fishers, and environmental nongovernmental organizations place a significantly higher priority on ecological over socioeconomic and governance performance indicators. Researchers placed even emphasis across all priorities. Results suggest that MIMNR should first focus on monitoring “abundance and size of native species” and demonstrates the capacity of the AHP to increase management effectiveness and improve the decision-making process. Furthermore, by identifying where discrepancies in preferences exist, the outcomes of this research can be used to enhance collaboration among stakeholders.  相似文献   
88.
The growing interest in promoting non-motorised active transport has led to an increase in the number of studies to identify the key variables associated with bicycle use, and especially those related to the bicycle mode choice problem. This paper presents a comprehensive survey of the modelling literature on the choice of the bicycle for utilitarian purposes, and summarises and assesses the evolution of the explanatory variables and methodologies used. We review both the evolution of the incorporation of latent variables in bicycle mode choice models and the critical role they play. The chronological evolution of the studies is divided into three stages —initial, intermediate and late — according to the different ways of introducing attitudinal or perceptual indicators and latent variables into the models. Our review shows that the incorporation of latent variables in bicycle choice models has increased in the last decade, with a progressive use of more sophisticated methodologies until the arrival of complex models that explicitly and properly deal with psychological latent variables. In fact, with the use of hybrid choice models, latent variables have nowadays become the core of bicycle mode choice models. Based on our review, a set of questions is proposed as a uniform measurement scale to identify attitudes towards bicycling. Recommendations for future research are also presented.  相似文献   
89.
为了弥补隧道监测数据缺失导致信息丢失的不足,从而能够更好地评价地铁隧道结构健康状况,基于压缩感知理论对健康监测数据进行处理,通过对运营地铁的结构健康监测数据进行压缩和重构,减少对原始监测数据的传输和存储压力,以提高获取的地铁健康相关数据的信息完备与可靠性,为隧道结构健康安全评价提供数据基础。在此基础上,构建运营地铁隧道安全风险指标评价体系,在获取完备数据的基础上,基于不确定性视角,采用云推理综合评估运营地铁隧道的可靠程度,以及时掌握运营地铁的安全状态,并找到影响其可靠性的关键风险,从而制定相应的管控措施。最后以武汉地铁2号线长汉区间监测点的累计沉降作为数据样本进行实例分析,结果显示压缩感知能使监测数据重构以获得完备数据,再利用逐级云推理得到安全风险等级云图与实际情况相符。  相似文献   
90.
城市轨道交通的工程可行性研究是一项涉及众多专业、复杂程度高、综合性强的系统工程,为更准确地把握客流特征,根据城市轨道交通工程可行性研究阶段客流预测的主要内容,就反映沿线区域特性的客流预测指标进行分析,包括高峰小时客流量、平均运距、换乘系数、区域OD和客流不均衡性等,以长春北湖线一期和成都10号线一期工程可行性研究为例,从与上位规划的符合性、线路特点的一致性和对工程方案的指导性3个方面阐述多指标结合的客流特征分析方法。  相似文献   
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