A decision support system for floating platform design     

J. Vasconcellos 《Ocean Engineering》1999,26(9):865

This paper describes a methodology developed for the preliminary design of floating production platforms. The preliminary design approach interlinks the mathematical design model with global optimization techniques. To illustrate the design procedure, the initial intermediate and final results are presented. They provide a clear understanding of the mathematical model and the decision support system. The preliminary design approach described here is based on the commercial software which is interfaced to what is called the FPS system and linked to a SEARCH package for design solutions. The paper summarizes the preliminary design approach, the mathematical model optimization and presents semisubmersible and TLP platform examples.  相似文献   

三西地区扶贫开发决策支持系统研究   总被引：3，自引：1，他引：2  

徐建华  刘俊清 《中国沙漠》1999,19(1):86-90

结合三西地区扶贫开发工作实践,研究了三西地区扶贫开发决策支持系统（ＤｅｃｉｓｉｏｎＳｕｐｐｏｒｔＳｙｓｔｅｍｏｆＰｏｖｅｒｔｙＡｌｅｖｉａｔｉｏｎａｎｄＤｅｖｅｌｏｐｍｅｎｔｉｎＳａｎｘｉＲｅｇｉｏｎ,简记为ＳＸＤＳＳ）。文章着重探讨了系统的用户需求及功能与结构设计,系统的特点及运行环境与应用问题。  相似文献   

A comparative analysis of a fixed thresholding vs. a classification tree approach for operational burn scar detection and mapping     

C.C. Kontoes  H. Poilvé  G. Florsch  I. Keramitsoglou  S. Paralikidis 《International Journal of Applied Earth Observation and Geoinformation》2009

The scope of this paper is to demonstrate, evaluate and compare two burn scar mapping (BSM) approaches developed and applied operationally in the framework of the RISK-EOS service element project within the Global Monitoring for Environment and Security (GMES) program funded by ESA (http://www.risk-eos.com). The first method is the BSM_NOA, a fixed thresholding method using a set of specifically designed and combined image enhancements, whilst the second one is the BSM_ITF, a decision tree classification approach based on a wide range of biophysical parameters. The two methods were deployed and compared in the framework of operational mapping conditions set by RISK-EOS standards, based either on sets of uni- or multi-temporal satellite images acquired by Landsat 5 TM and SPOT 4 HRV. The evaluation of the performance of the two methods showed that either in uni- or multi-temporal acquisition mode, the two methods reach high detection capability rates ranging from 80% to 91%. At the same time, the minimum burnt area detected was of 0.9–1.0 ha, despite the coarser spatial resolution of Landsat 5 TM sensor. Among the advantages of the satellite-based approaches compared to conventional burn scar mapping, are cost-efficiency, repeatability, flexibility, and high spatial and thematic accuracy from local to country level. Following the catastrophic fire season of 2007, burn scar maps were generated using BSM_NOA for the entirety of Greece and BSM_ITF for south France in the framework of the RISK-EOS/GMES Services Element project.  相似文献   

数字黑河的思考与实践3:模型集成   总被引：3，自引：0，他引：3  

李新  程国栋  康尔泗  徐中民  南卓铜  周剑  韩旭军  王书功 《地球科学进展》2010,25(8):851-865

介绍了"数字黑河"模型集成研究的进展.①流域科学研究中的模型集成由发展流域集成模型和建模环境这2个主题所构成,前者可概括为"水-土-气-生-人"集成模型,后者是支持集成模型的高效开发的软件工具,注重于应用先进的信息技术为建模提供支撑.②将模型集成分为知识途径和技术途径,讨论了建模环境在模型集成中的作用,以及科学模型和流域管理模型的关系.③回顾了黑河流域模型集成的总体目标是发展两种类型的集成模型,其中第一种回应科学目标,是地球系统模型在流域尺度上的具体体现,以建成能够综合反映流域水文-生态-经济相互作用的模型为标志;第二种集成模型回应管理目标,以建成空间显式的流域水资源决策支持系统为目标.④对黑河流域已有的水文、地下水、水资源、陆面过程、土地利用、生态、社会经济与生态经济建模工作做了系统的综述.⑤分析了黑河流域集成模型研究中存在的问题和所面临的挑战.  相似文献   

Knowledge-based systems as decision support tools in an ecosystem approach to fisheries: Comparing a fuzzy-logic and a rule-based approach   总被引：1，自引：0，他引：1  

Astrid Jarre  Barbara Paterson  Coleen L. Moloney  David C.M. Miller  John G. Field  Anthony M. Starfield 《Progress in Oceanography》2008,79(2-4):390

In an ecosystem approach to fisheries (EAF), management must draw on information of widely different types, and information addressing various scales. Knowledge-based systems assist in the decision-making process by summarising this information in a logical, transparent and reproducible way. Both rule-based Boolean and fuzzy-logic models have been used successfully as knowledge-based decision support tools. This study compares two such systems relevant to fisheries management in an EAF developed for the southern Benguela. The first is a rule-based system for the prediction of anchovy recruitment and the second is a fuzzy-logic tool to monitor implementation of an EAF in the sardine fishery. We construct a fuzzy-logic counterpart to the rule-based model, and a rule-based counterpart to the fuzzy-logic model, compare their results, and include feedback from potential users of these two decision support tools in our evaluation of the two approaches. With respect to the model objectives, no method clearly outperformed the other. The advantages of numerically processing continuous variables, and interpreting the final output, as in fuzzy-logic models, can be weighed up against the advantages of using a few, qualitative, easy-to-understand categories as in rule-based models. The natural language used in rule-based implementations is easily understood by, and communicated among, users of these systems. Users unfamiliar with fuzzy-set theory must “trust” the logic of the model. Graphical visualization of intermediate and end results is an important advantage of any system. Applying the two approaches in parallel improved our understanding of the model as well as of the underlying problems. Even for complex problems, small knowledge-based systems such as the ones explored here are worth developing and using. Their strengths lie in (i) synthesis of the problem in a logical and transparent framework, (ii) helping scientists to deliberate how to apply their science to transdisciplinary issues that are not purely scientific, and (iii) representing vehicles for delivering state-of-the-art science to those who need to use it. Possible applications of this approach for ecosystems of the Humboldt Current are discussed.  相似文献   

A data mining based approach to predict spatiotemporal changes in satellite images     

W. Boulila  I.R. Farah  K. Saheb Ettabaa  B. Solaiman  H. Ben Ghézala 《International Journal of Applied Earth Observation and Geoinformation》2011

The interpretation of remotely sensed images in a spatiotemporal context is becoming a valuable research topic. However, the constant growth of data volume in remote sensing imaging makes reaching conclusions based on collected data a challenging task. Recently, data mining appears to be a promising research field leading to several interesting discoveries in various areas such as marketing, surveillance, fraud detection and scientific discovery. By integrating data mining and image interpretation techniques, accurate and relevant information (i.e. functional relation between observed parcels and a set of informational contents) can be automatically elicited.  相似文献   

基于MODIS植被指数的太湖蓝藻信息提取方法研究   总被引：4，自引：1，他引：3  

李亚春  孙佳丽  谢志清  谢小萍 《气象科学》2011,31(6):737-741

有效地提取蓝藻水华信息对分析蓝藻动态分布有重要意义,而卫星遥感技术是进行太湖水质监测与保护的措施之一.本文以2007年7月25日Terra/MODIS数据为主要数据源,用比值植被指数(Irv)、归一化植被指数(Indv)和增强型植被指数(Iev),研究提取太湖蓝藻信息.结果表明:植被指数可以有效提取遥感影像中的蓝藻水华信息,其中Indv是应用效果较好的植被指数之一;在掩膜处理后,用Indv提取了太湖蓝藻的面积分布信息,效果较好;此外,选取Indv为测试变量,利用决策树分类法,有效地把蓝藻水华高浓度覆盖区、中浓度覆盖区和轻浓度覆盖区分开来,为准确掌握太湖蓝藻发生、发展趋势和发生程度提供可靠信息.  相似文献   

Assessing the quality of data required to identify effective marine protected areas     

《Marine Policy》2014

This study aims to evaluate the effectiveness of currently available substrate data to designate marine reserves to meet conservation objectives. The case study site is Lyme Bay (approx. 2460 km²), in the western English Channel. An area of 240 km² in Lyme Bay was designated ‘closed to bottom dredging’ in July 2008 with the aim of protecting reefs which are an important habitat for Eunicella verrucosa (pink sea fan). The effects of using different substrate data resolution on the selection of sites to protect a range of biotopes using the Marxan package are determined. The effect of including a closed area on the efficiency of a marine reserve network is also investigated. Findings suggest that substrate data did not capture the biodiversity of the area and that using no data at all was equally effective. If low resolution data are all that are available then other options, such as expert opinion, or other data, such as activity use information could be used instead. Including a predefined closed area into the analysis led to an increase in area required to meet conservation goals using high resolution biotope data. It also increased the area of the reserve using the three substrate layers with no increase in protection for biotopes. This suggests that when designing networks of marine protected area sites, including current protected areas may be inefficient, resulting in larger areas being protected with no increased conservation of marine biodiversity. Policy makers must be prepared to adapt management in light of these findings and be aware of the shortcomings of the data available for use in marine conservation planning.  相似文献   

Positive and negative spillover of pro-environmental behavior: An integrative review and theoretical framework     

《Global Environmental Change》2014

A recent surge of research has investigated the potential of pro-environmental behavior interventions to affect other pro-environmental behaviors not initially targeted by the intervention. The evidence evaluating these spillover effects has been mixed, with some studies finding evidence for positive spillover (i.e., one pro-environmental behavior increases the likelihood of performing additional pro-environmental behaviors) and others finding negative spillover (i.e., one pro-environmental behavior decreases the likelihood of additional pro-environmental behaviors). Different academic disciplines have investigated this question, employing different methodologies and arriving at divergent findings. This paper provides a unifying theoretical framework and uses the framework to review the existing research on pro-environmental behavior spillover. Our framework identifies different decision modes as competing mechanisms that drive adoption of initial pro-environmental behaviors, with different consequences for subsequent pro-environmental behaviors, leading to positive, negative, or no spillover. Attribution of the initial pro-environmental behavior to either an external motivator (e.g., a price signal) or internal motivator (e.g., self-identity) also matters. In addition, the characteristics of and similarity between initial and subsequent pro-environmental behaviors can be expected to moderate predicted spillover effects. We explore the implications of our model for policymakers and practitioners, and suggest key areas where future research on the topic would be most beneficial.  相似文献   

基于多波束背向散射强度信号的海底表层沉积物粒度分类研究——以澳洲Joseph Bonaparte湾为例   总被引：1，自引：0，他引：1  

徐韦  程和琴  黄知  郑树伟  陈钢 《海洋学报》2019,41(1):172-182

近海海底地形探测与沉积物精确分类对涉海工程建设、生物栖息地反演以及海底资源勘查与开发具有重要的现实意义。以澳洲Joseph Bonaparte湾为例，利用多波束测深技术获取了该海湾约880 km2水域的水深数据与背向散射强度信号，结合同步采集的54个海底表层沉积物样品，通过随机决策树模型对该海域海底表层沉积物进行了分类研究。结果表明:（1）利用随机决策树模型分析该海域沉积物类型与背向散射强度的关系时，当模型内部参数设置:树的总数为200，最小分裂节点为2，每棵树的最大分裂级数为5时，可提高预测准确率；（2）该参数设置下，利用13°和37°入射角的背向散射强度预测该海域沉积物类型时，准确率最高，其值为83.3%，且在研究海域，砂质砾和砾质砂分布在背向散射强度较强的深槽或海沟等地区，而砾质泥质砂和含砾泥质砂主要分布在背向散射强度较弱的浅水海域。分析还发现，当水深数据作为预测海底表层沉积物类型的特征变量时，有可能降低最终预测结果的准确率。  相似文献