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1.
宣森 《广东海洋大学学报》1993,(1)
将专家系统技术与常规控制、模糊控制、超前控制、仿人智能操作控制以及计算机控制技术相结合,设计了一种新的基于专家系统决策的多模式控制(MCDBES)。经试验和实际运行结果表明,MCDBES系统对未知数学模型的被控对象,具有良好的控制性能。本文提出的MCDBES已成功地应用于燃油陶瓷窑炉计算机控制系统。 相似文献
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Prediction of coastal hazards due to climate change is fraught with uncertainty that stems from complexity of coastal systems, estimation of sea level rise, and limitation of available data. In-depth research on coastal modeling is hampered by lack of techniques for handling uncertainty, and the available commercial geographical information systems (GIS) packages have only limited capability of handling uncertain information. Therefore, integrating uncertainty theory with GIS is of practical and theoretical significance. This article presents a GIS-based model that integrates an existing predictive model using a differential approach, random simulation, and fuzzy set theory for predicting geomorphic hazards subject to uncertainty. Coastal hazard is modeled as the combined effects of sea-level induced recession and storm erosion, using grid modeling techniques. The method is described with a case study of Fingal Bay Beach, SE Australia, for which predicted responses to an IPCC standard sea-level rise of 0.86 m and superimposed storm erosion averaged 12 m and 90 m, respectively, with analysis of uncertainty yielding maximum of 52 m and 120 m, respectively. Paradoxically, output uncertainty reduces slightly with simulated increase in random error in the digital elevation model (DEM). This trend implies that the magnitude of modeled uncertainty is not necessarily increased with the uncertainties in the input parameters. Built as a generic tool, the model can be used not only to predict different scenarios of coastal hazard under uncertainties for coastal management, but is also applicable to other fields that involve predictive modeling under uncertainty. 相似文献
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应用模糊综合评价方法对大连臭水套海域疏浚物预选倾倒区的水质状况进行了评价,得到了有益的结论。 相似文献
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Generally, the underwater flight vehicle (UFV) depth control system operates with the following problems: it is a multi-input multi-output (MIMO) system, it requires robustness, a continuous control input, and further, it has the speed dependency of controller parameters. To solve these problems, an expanded adaptive fuzzy sliding mode controller (EAFSMC), which is based on the decomposition method designed by using an expert knowledge and the decoupled sub-controllers and composition method designed by using the fuzzy basis function expansions (FBFEs), is proposed. To verify the performance of the EAFSMC, the depth control of UFV in various operating conditions is performed. Simulation results show that the EAFSMC solves all problems experienced in the UFV depth control system online. 相似文献
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Risk-based decision-making for drilling waste discharges using a fuzzy synthetic evaluation technique 总被引:5,自引:0,他引:5
Offshore petroleum drilling wastes contain toxic substances that are potentially harmful to the marine ecosystem. Despite environmentally benign characteristics, wastes associated with synthetic-based fluids still contain a certain amount of pollutants due to contamination with formation oil and the presence of trace heavy metals in barite, which may pose risk when discharged into the marine environment. A framework is presented here for a decision support system for the selection of the best drilling waste discharge option. Uncertainties in the quantification of risk, cost and technical feasibility are expressed by fuzzy numbers. An analytical hierarchy process with a technique called fuzzy synthetic evaluation is employed to determine the best management alternative (discharge scenario). 相似文献
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在收集了大量的地质资料的基础上,结合地理信息系统的数据库和空间分析功能,通过专家一层次分析法确定权重,运用模糊评判法对南充市城市地质环境质量进行分区评价。地质环境是城市建设和发展的基础,随着城市化进程加快,城市地质环境问题越来越突出。因此,对城市地质环境条件进行定量评价,对于城市规划和建设具有重要的指导意义:评价的结果将南充市城市地质环境划分为3个区11个亚区,各区地质环境质量有明显的差异,并提出城市建设合理的发展方向。 相似文献
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简要概述了遥感影像匹配中,误匹配点剔除的常用方法.对SIFT特征描述子生成及其匹配、粗糙模糊C-均值方法聚类分析的原理方法进行了详细论述.针对SIFT方法匹配出的大量点对,将不同时相,不同传感器、不同分辨率影像广义划分为同分辨率和不同分辨率.基于同分辨率影像匹配点对问连线具有相同的距离及斜率、不同分辨率影像匹配点对间连线的延长线交于一点的几何约束条件,利用粗糙模糊C-均值模型聚类分析方法对点对快速剔除误匹配点后,对剔除的结果利用最小二乘方法进行精匹配,结果达到亚像素.最后,通过对不同时相、不同分辨率、不同传感器的多源遥感影像实验分析验证了该方法的适用性、可靠性及精确性. 相似文献