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排序方式: 共有695条查询结果,搜索用时 15 毫秒
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   
2.
利用上海天文台的照相底片资料,确定了疏散星团NGC6530天区364颗恒星的自行和成员概率,并对有关自行测定的方法、结果和精度等问题作了较为详细的介绍和讨论。使用的底片历元差为87年,全部恒星自行中误差的均方根值为1.09mas/a。  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   
5.
CHEN  Shouyu 《中国海洋工程》2001,(4):453-466
In the process of concept design of offshore platforms, it is necessary to select the best from feasible alternatives through comparison and filter. The criterion set, used to evaluate and select the satisfying alternative, consists of many qualitative and quantitative factors. Therefore, the selection is a problem of multicriteria and semi- structural decision- making. Different from traditional methods in semi- structural decision- making, a new framework and methodology is presented in this paper for evaluation of offshore platform alternatives. First, the criterion set is established for the evaluation of alternatives. Next, the approach is studied to construct the relative membership degree matrix, in which both qualitative and quantitative factors are consistent with the uniform calculating standard. And then a new weight-assessing method is developed for calculation of the weights based on the relative membership degree matrix. Finally, a multi-hierarchy fuzzy optimum model is adopted to select t  相似文献   
6.
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   
7.
Hyun-Sik Kim  Yong-Ku Shin   《Ocean Engineering》2007,34(8-9):1080-1088
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   
8.
废弃海洋桩基平台拆除方案的系统决策研究   总被引:2,自引:0,他引:2  
海洋平台拆除是一项复杂的、受多种因素制约的、涉及许多技术领域的综合性系统工程。采取适当的拆除方案是工程安全、经济、环保地进行的基础和保证。针对这一问题,文章对拆除方案的评估进行了系统的研究,从环境、工艺、安全、经济、工期的角度建立了拆除方案评估指标体系,并综合运用群决策层次分析理论和模糊数学理论对拆除方案进行系统的评估。经实例验证,所建立的评估指标体系,可科学、公正、快捷地对方案进行评估,为决策者提供科学的决策基础。  相似文献   
9.
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   
10.
南充市城区地质环境质量分区模糊评价   总被引:3,自引:0,他引:3       下载免费PDF全文
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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