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141.
基于知识的洞庭湖湿地遥感分类方法   总被引:2,自引:0,他引:2  
湿地遥感影像分类是遥感研究的一大难题。分析洞庭湖不同湿地类型在遥感影像上的光谱曲线规律,利用两个季节的洞庭湖ETM数据,并辅助以物候特征和地面GIS信息,通过遥感软件Erdas Image的专家分类知识库建立决策树分类方法,结合研究区的DEM进行洞庭湖湿地的影像分类,通过专家分类器分层次实现了包括水体、泥沙滩地、防护林滩地、湖草、芦苇滩地和苔草滩地以及其他水体7种湿地类型的分类。相比传统分类方法,专家分类过程以规则为基础,可以同时利用多个条件进行分类,减少了数据处理时间,同时还提高了分类精度,最终得到试验区较为可靠的遥感分类图像。  相似文献   
142.
Sustainability has become a very significant research topic as it impacts many different manufacturing industries. Therefore, the technologies for monitoring, analysing, evaluating and optimising the sustainability performance of manufacturing processes and systems are very critical for decision makers on the shop floor. This paper introduces a decision guidance management system that provides actionable recommendations through quantitative analysis of the sustainability measures of manufacturing processes and systems based on life cycle assessment. The system determines decision preferences through dynamically collected data and decision makers' responses, taking into account the prevailing constraints. Optimal decisions can be derived using mathematical and constraint programming. By using decision guidance query language, this methodology allows users to make optimal decisions without an extensive mathematical or operations research background. Knowledge of relational databases is sufficient for a user to formulate the optimisation problem and obtain optimal solutions. The methodology is demonstrated with a machining operation case study, in which a list of sustainability metrics are identified and sustainability modelling methods are proposed. Important sustainable machining performance measures are optimised, resulting in actionable recommendations.  相似文献   
143.
This report proposes a method for assessing resilience-building components in coastal social–ecological systems. Using the proposed model, the preferences of experts in Masan Bay (South Korea) and Puget Sound (USA) are compared. A total of 30 management objectives were determined and used to build a hierarchic tree designed using the principles of the Analytic Hierarchy Process (AHP). Surveys were performed with 35 Puget Sound experts using face-to-face interviews and with 28 Masan Bay experts by mail. The results demonstrate that the legal objective, which enables legislation, was the highest preferred component in both regions. The knowledge translation variable was also given a high preference score in both regions. An analysis of variance (ANOVA) showed that the Puget Sound experts significantly favored attention to education, habitat restoration and species protection objectives in comparison to the Masan Bay experts. The Masan Bay experts placed greater emphasis on legislation and the type of institutional design than did the Puget Sound experts. Using cluster analysis, four distinct groups of respondents were independently identified in Puget Sound and three groups were identified in Masan Bay. One unique subgroup in the Puget Sound experts group, which was characterized by its high preferences for habitat restoration and species protection, was not observed in Masan Bay. Demographic variables (length of career and role in coastal issue) failed to account for the differences in groupings and preferences in either region, except for the variable ‘favoring information source’ in the Puget Sound group. This finding implies that the demographic information was not related to differences in group opinions in both regions. The analysis framework presented here was effective in identifying expert preferences regarding the overall structure and emphasis in coastal management programs. Thus, this framework can be applied towards coastal policy development.  相似文献   
144.
Controversy between alternative uses of forests in Finnish Upper Lapland has been going on for decades, and in recent years it has been escalated to a serious conflict. The core of the conflict is the adverse impacts of forestry on old forests which are important grazing areas for reindeer and which are regarded as intact nature and wilderness areas. This paper describes the experiences of applying multi-criteria decision analysis interview approach on this conflict. The approach provides tools for structuring the problem and preferences of the stakeholders as well as for analyzing the effects of different alternatives in a common framework. We focus on the practical experiences gained from the application of this approach in this context. Multi-criteria decision analysis was found to be a useful approach to evaluate the economic, ecological and cultural aspects of this intense conflict. The obtained experiences also support the view that the approach works best when tightly integrated into the planning process.  相似文献   
145.
Adaptive management for a turbulent future   总被引:3,自引:0,他引:3  
The challenges that face humanity today differ from the past because as the scale of human influence has increased, our biggest challenges have become global in nature, and formerly local problems that could be addressed by shifting populations or switching resources, now aggregate (i.e., "scale up") limiting potential management options. Adaptive management is an approach to natural resource management that emphasizes learning through management based on the philosophy that knowledge is incomplete and much of what we think we know is actually wrong. Adaptive management has explicit structure, including careful elucidation of goals, identification of alternative management objectives and hypotheses of causation, and procedures for the collection of data followed by evaluation and reiteration. It is evident that adaptive management has matured, but it has also reached a crossroads. Practitioners and scientists have developed adaptive management and structured decision making techniques, and mathematicians have developed methods to reduce the uncertainties encountered in resource management, yet there continues to be misapplication of the method and misunderstanding of its purpose. Ironically, the confusion over the term "adaptive management" may stem from the flexibility inherent in the approach, which has resulted in multiple interpretations of "adaptive management" that fall along a continuum of complexity and a priori design. Adaptive management is not a panacea for the navigation of 'wicked problems' as it does not produce easy answers, and is only appropriate in a subset of natural resource management problems where both uncertainty and controllability are high. Nonetheless, the conceptual underpinnings of adaptive management are simple; there will always be inherent uncertainty and unpredictability in the dynamics and behavior of complex social-ecological systems, but management decisions must still be made, and whenever possible, we should incorporate learning into management.  相似文献   
146.
根据重大城市的化学事故后果评估与应急救援的实际需要出发,提出了研制辅助决策系统任务需求和设计构想,阐述了该系统的系统结构、系统实现的流程和系统功能,并做了可行性分析。系统的模块包括:化学品基础信息模块、化学事故类型划分模块、地理信息系统模块、化学源周围道路交通模块、实时的天气预报模块、数学模型模块、危害后果评估模块、救援方案生成模块、人员疏散撤离方案生成模块、人机交互模块。系统与地理信息系统(G IS)、卫星导航系统(GPS)、遥感成像技术结合后能够实现精确定位、快速评估。将物联网技术与系统结合,还可实现对大型固定化学源远程时时监控,确保在事故发生后第一时间掌握信息,为后果评估和应急救援赢得时间,将化学突发事故的危害降到最低。该系统在信息化条件下,较好地为决策者进行化学事故后果评估,为应急救援决策提供了依据,可大幅度提高应急救援效能。  相似文献   
147.
重大冰雪灾害应急管理能力的评价——以湖南省为例   总被引:1,自引:0,他引:1  
徐选华  李芳 《灾害学》2011,26(2):130-137
针对重大冰雪灾害应急管理的复杂性,基于湖南冰雪灾害案例以及国内外自然灾害及其应急管理的相关文献,提出了重大冰雪灾害应急管理能力评价指标结构。运用熵权法和群决策方法确定指标综合权重,采用群决策方法获得专家群体对一级评价指标的综合偏好,形成评价城市的综合评价矩阵,运用灰色综合评价模型求出各个评价城市应急管理能力的排序向量。最后以湖南省冰雪灾害为案例进行了应用。  相似文献   
148.
Hunt MR 《Disasters》2011,35(3):606-622
Expatriate health care professionals frequently participate in international responses to natural disasters and humanitarian emergencies. This field of practice presents important clinical, logistical and ethical challenges for clinicians. This paper considers the ethics of health care practice in humanitarian contexts. It examines features that contribute to forming the moral landscape of humanitarian work, and discusses normative guidelines and approaches that are relevant for this work. These tools and frameworks provide important ethics resources for humanitarian settings. Finally, it elaborates a set of questions that can aid health care professionals as they analyse ethical issues that they experience in the field. The proposed process can assist clinicians as they seek to establish their moral bearings in situations of ethical complexity and uncertainty. Identifying and developing ethics resources and vocabulary for clinical practice in humanitarian work will help health care professionals provide ethically sound care to patients and communities.  相似文献   
149.
耕地保护面临的形势及其对策研究   总被引:2,自引:0,他引:2  
通过运用SWOT分析法,对我国城乡生态经济交错区农地保护的外部环境的机会与威胁、内部环境的优势与劣势进行了战略分析,其目的在于寻找新形势下农地保护的正确战略决策,以解决我国吃饭与建设的矛盾,实现土地资源的可持续利用。通过研究得出:农地保护面临着严峻的国内外形势,政府应该扬长避短,积极应对。  相似文献   
150.
ABSTRACT: Unrelenting pressure on limited surface water supplies requires increasingly sophisticated water management approaches. Climate forecasts of seasonal precipitation and temperature are potentially useful, but the operational water management community currently underutilizes them. However, some agencies in Arizona took unprecedented advantage of forecasts for a potentially wet winter during the 1997–1998 El Niño event. This study investigates use of this information through a series of semi‐structured in‐depth interviews with key personnel from agencies responsible for emergency management and water supply; their jurisdictions ranged from urban to rural and local to regional. Interviews investigated information acquisition, interpretation, and incorporation into specific decisions and actions. While unprecedented actions were taken by some water management agencies and no agencies implemented inappropriate measures, some missed opportunities for more effective response, primarily through inaction. This study reveals a variety of technical factors and institutional characteristics affecting forecast use. Study findings emphasize the need for: (a) closer ongoing relationships between forecast producers and users, (b) increased institutional flexibility to exploit the increasing skill of seasonal climate forecasts, (c) demonstration projects of effective forecast use, and (d) a regional forum to facilitate information transfer between the hydro‐climatic research community and operational water managers.  相似文献   
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