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61.
Increasing interest in implementing an ecosystem-based management approach has made stakeholder involvement vital and has highlighted the need for an effective participatory framework. In this study we used a participatory geographic information systems (PGIS) framework to collaboratively map the marine resources of the transboundary Grenadine Islands with a broad range of stakeholders from the two sovereign nations. We found the application of PGIS allowed the collective resolution of an appropriate mapping scale and a locally relevant habitat classification scheme that would not only serve the needs of resource managers, but could also be understood by resource users. Furthermore, multi-level stakeholder involvement in the mapping process captured resource use profiles and other fishing-related attributes, gave credibility to local knowledge and ownership of information, and was instrumental in building capacity to access and use the produced information. Lessons learned included the importance of investing considerable time early in the participatory process, which was later rewarded by stakeholder buy-in and led to financial and in-kind support. Furthermore, hosting the information in multiple formats on a project website has resulted in easy access and use by a wide range of stakeholders over a cross-country scale. We believe our experiences will be valuable to other practitioners considering using PGIS, particularly for those working in similar resource-limited, developing nation contexts. 相似文献
62.
以贵州省纳雍县为研究区,基于地理信息系统(GIS)平台,采用Logistic回归模型评价区域滑坡易发性。选取高程、坡度、坡向、地表曲率、岩性、到公路距离、到水系距离和到断层距离8项影响因子,应用Logistic回归模型拟合描述滑坡发生与各项因子关系的回归方程。在此基础上,预测研究区内滑坡易发性的概率值,并将研究区划分为5个易发级别。结合历史滑坡分布,对滑坡易发性分区的合理性进行验证,结果表明滑坡易发性分区图和实际滑坡分布情况吻合较好。此外,应用受试者工作特征曲线对模型结果进行评价,结果显示,曲线下面积AUC值为0.774,Logistic回归模型的预测精度较好。 相似文献
63.
在直立式防波堤的抗滑、抗倾可靠度分析中,通常将结构与基床间的摩擦系数f,直立式防波堤在水中的重力G及其引起的稳定力矩MG均作为定值处理,而忽略三者的变动对可靠度的影响。以秦皇岛港燃料油基地的直立式防波堤为例,采用JC法、映射变换法及Monte Carlo模拟3种方法分别计算了摩擦系数f,自重G及其引起的稳定力矩MG作为定值和变量时直立式防波堤抗滑、抗倾的可靠性指标。结果表明:将摩擦系数f,自重G及其引起的稳定力矩MG均作为变量处理,得到的可靠性指标更精确、更符合实际情况;摩擦系数f的变动对直立式防波堤的可靠度影响较小,而自重G及其引起的稳定力矩MG二者的变动对直立式防波堤的可靠度影响较大。 相似文献
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65.
以贵州省纳雍县为研究区,基于地理信息系统(GIS)平台,采用Logistic回归模型评价区域滑坡易发性。选取高程、坡度、坡向、地表曲率、岩性、到公路距离、到水系距离和到断层距离8项影响因子,应用Logistic回归模型拟合描述滑坡发生与各项因子关系的回归方程。在此基础上,预测研究区内滑坡易发性的概率值,并将研究区划分为5个易发级别。结合历史滑坡分布,对滑坡易发性分区的合理性进行验证,结果表明滑坡易发性分区图和实际滑坡分布情况吻合较好。此外,应用受试者工作特征曲线对模型结果进行评价,结果显示,曲线下面积AUC值为0.774,Logistic回归模型的预测精度较好。 相似文献
66.
张勇 《西南交通大学学报(英文版)》2006,14(2)
Introduction Variational inequality is one of the most interest-ing and important mathematical problems and hasbeen studied intensively in the past years since theyhave wide applications to mechanics, physics, opti-mization and control, nonlinear programm… 相似文献
67.
概念格的分层及逐层建格法 总被引:4,自引:0,他引:4
给出了分层概念格重要性质:同层概念不可比和每个概念至少被1个上层的概念覆盖.得到了概念格上的对象映射和属性映射的一般计算公式和在对象化简过程中格结构不变的定理.由上述性质和定理,给出建格算法.此方法以概念格分层为基础,逐层建格.因为在建每层格的节点的过程中同时进行筛选,所以不会生成冗余重复的格节点. 相似文献
68.
This paper presents solutions to the function generation problems of Stephenson Ⅲ six-link mechanism with the maximum precision positions for the first time using homotopy method with an improved path-tracking scheme. The new path-tracking scheme is based on the characteristics of the zero sets of homotopy function for polynomial mapping and thus the tracking speed is dramatically increased. 相似文献
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70.
Over the last decade, insights from the strategic management discipline have increasingly been applied to ports. A review of literature shows that in the analysis of port authority strategy, mainly outside-in approaches are applied. This paper adds to the emerging understanding of the port authority’s strategy by applying a cognitive perspective. Specifically, the strategic cognition of firms’ executives is one of the explanatory variables behind firms’ strategic decisions. Furthermore, cognitions are influenced by the organisational contexts in which port authority executives have worked. As a result, managerial “mental maps’ may vary across industry contexts and over time. This research investigates the strategic cognition of a global set of port authority executives through a survey-based instrument. The results show that, to a large extent, PAs resemble “regular” for-profit companies, but that they possess some specific beliefs that distinguish them from “regular” companies. 相似文献