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1.
为了对中国玉米产业安全进行动态评价与变化趋势分析,采用基于熵权法和模糊综合评价法建立玉米产业系统安全综合评价模型,利用历史及预测数据对1999—2017 年玉米系统安全度进行估算,据此对中国玉米产业系统安全状态进行总体评价。结果表明:近年来中国玉米产业安全形势不容乐观,2007—2017 年中国玉米产业的安全状态波动加剧,玉米及其副产品进口量大幅增加,进口依赖性增强,国际资本对中国玉米产业股权控制加强则是影响玉米安全的主要因素。据此提出积极应对玉米产业外资进入、降低玉米进口国别依存度、努力掌握玉米贸易定价权等对策。 相似文献
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The two-level handstand pendulum system based on fuzzy control is designed. It is impossible to adopt classical control theory, for the mathematical modeling of the system is nonlinear, the fuzzy control is proposed to improve the former linear control algorithms. For the key to fuzzy control is control rule, it becomes most important to design suitable fuzzy rules. Two methods, one based on experience and the other based on system simulation, are presented to set u Pan effective rule base. The practice proves that the control result is of well stability. A control example for two-level handstand pendulum system shows that the control law is efficient and more robust than the classical state feedback optimal control law with respect to errors produced by the external disturbances. 相似文献
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Based on analyses of the main factors that influence the supplying risks in automobile parts enterprises within our country,a supplying risks judgment system is established. To determine the risks, a fuzzy comprehensive judge method is put forward with AHP method. In the end, with an example of a company, supply risks are analyzed, which provides a referential method for determining supplying risks in automobile parts enterprises. 相似文献
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A robust method for determining the component safety factor and structural safety factor of steel truss bridge is developed based on elastic modulus reduction method (EMRM). A procedure of two-level safety analysis and structural optimization is presented by means of the linear FEA iteration and the generalized yield criterion to take multiple internal forces into consideration. The strategy of elastic modulus adjustment is derived according to the principle of conversation of energy. The element bearing ratio (EBR) in every step can be obtained, and the first and last EBRs are employed to determine component safety factor and the structural safety factor for two-level structural safety evaluation of steel truss bridge. Those components with higher or lower EBR than the referenced EBR can be identified. By taking the quantitative relationship of the two level safety factors, a structural optimization scheme with better distribution of the EBR and saving material consumption can be achieved by adjusting the sectional strength of components with higher and lower EBR. Numerical examples show that the proposed method is promising with satisfying accuracy. The analysis of structural safety and optimization can be implemented by using the linear iteration while complicated nonlinear analysis in classical scheme is avoided. 相似文献
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针对目前农业产业集群评价研究现状较少状况,尝试运用模糊数学方法对指标数据运用隶属度函数处理,以一级模糊综合评价向量作为神经网络评价模型的输入,再运用神经网络模型对农业产业集群进行评价,神经网络的非线性处理能力使农业产业集群评价更加科学化,并以连云港农业产业集群评价为例给出了实证研究。 相似文献
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以模糊数学为指导,建立黑全麦饺子皮的感官评价体系。运用模糊二元对比决策法,排序优选出黑全麦饺子皮感官评价指标,通过0~4 评分法确定评价指标的权重分配,以百分制构建黑全麦饺子皮感官评价体系,并将此感官评价体系应用于评价不同面团熟化时间(20、25、30、35 min)制作的黑全麦饺子皮。结果表明,排序优选出8 项可用于黑全麦饺子皮感官评价的指标,其中表观状态的权重为0.20,色泽、耐煮性和软硬度的权重均为0.15,韧性、粘牙性和食味的权重均为0.10,颗粒感权重为0.05;面团熟化25 min 制作的黑全麦饺子皮感官评价总分最高,整体感官品质最佳。综上,基于模糊数学建立的感官评价体系可以准确地评价黑全麦饺子皮感官品质。 相似文献
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Improvement of Fuzzy Comprehensive Evaluation Method 总被引:1,自引:0,他引:1
Fuzzy comprehensive evaluation is an effective method to evaluate many comprehensive problems and is widely used in environmental engineering, mining engineering and so on. The popular fuzzy comprehensive evaluation method is analyzed and some irrationality is found in its max-min algorithm and maximal subordinate degree principle. An altered arithmetic is proposed, and a technique of synthetic grade is introduced as the final evaluating result. The application case proves that the evaluating result with new method is more reliable. 相似文献
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Based on analyzing factor of the effect of technology innovation in enterprise,the distinctive multiple technology innovation system is established. The computing method of index weight is discussed in the face of multiple objective decision making, and the authors construct the quantitative analysis model of multiple fuzzy evaluation through fuzzy transform. With the present situation of certain manufacturing enterprise, some suggestions are given in the end after quantitative analyzing. 相似文献
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《保鲜与加工》1997,(6):108-112
Based on analyses and studies on basic knowledges such as expert system,engineering database and language,a model frame of Expert Decision Design System EDDS is built up,which consists of expert system as the main component.An example of EDDS application in aseismic building structure type choosing is presented,while its feasibility and advantages are demonstrated simultaneously. 相似文献
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The author establishes a risk evaluation index system of technology innovation according to the character of technology innovation . In this index system, technology risk, the capability of coporate risk, market risk are taken into consideration as well as the situition of the interior and the exterior of coporate besides the difficulty of the technology. The index-weighted is calculated with AHP and the whole process of fuzzy comprehensive evaluation is developed , which gives the accurate evaluation for the echnology innovation risk and can be guided by an enterprise for control the risk. At last, an example is given. 相似文献
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There are many risks that influence freeway project financing and the influence of these risks differ by project stage. However, it is impossible to analyze the total risk of project financing objectively and accurately merely using the fuzzy or grey evaluation methods. These methods cannot reflect the dynamic characteristics of financing risks during freeway project construction. A dynamically grey fuzzy comprehensive evaluation method was established and used to evaluate the financing risks of a freeway project. The results indicate that this method can not only make full use of the rich experience of the experts, but also reduce the influence of subjective factors. In addition, this method can reflect the dynamic characteristics of the financing risks during freeway project construction. Investors therefore can pertinently prevent and control financing risks based on the results of the evaluation of financing risks in every stage of the project. A demonstration shows that the method is suitable for comprehensive evaluation of financing risks of infrastructure projects such as freeways. 相似文献
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The connections of frame structure elements at a node are ofen an elastic connection between hinged and rigid.In this paper,the stiffness matrix and the loading transfer matrix of frame element with turn elastic connections is deduced,the cross shear effect has been taken into consideration simultaneously.The stiffness matrices of some bar elements,such as both ends of the bar are hinged or rigid and one end is hinged but the other is rigid,are special cases of the stiffness matrices presented in this paper.After pointing out that the elastic coefficient at a node of a bar element with elastic joint is really a fuzzy quantity,the fuzzy stiffness matrix of the bar element is obtained,and a solution to structural fuzzy finite element equilibrium equations is presented.The fuzzy solution obtained from above is not only containing the solution of ordinary finite element method but also providing some additional informations with practical value.[WT5HZ] 相似文献
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The alarm system in controlling the automobile speed is presented, without change of the original structure, and the design scheme of the system implements sampling, measurement, computing, real-time alarm and delay-time control for the automobile speed according to the safety of the automobile driving. Then, the speed is randomly stored so as to insure the correct data and to effectively analyze the data. Especially, the key techniques of the speed measurement and the refresh storage are pesented in datail in the system. 相似文献
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Evaluation of network study result is key job that network teaching and network teaching system developments. Fuzzy comprehensive evaluation method is introduced to analyze the network study based on the network study evaluation system index system combining with the characteristics of the combinative network study. The paper puts forward the model of the fuzzy comprehensive evaluation of network study, it proves the fuzzy comprehensive evaluation method is a kind of valid method than other traditional method in network learning through an experiment. 相似文献
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以中国渔政管理指挥系统作为评价对象,将该系统的信息化建设的长远目标和近期目标、内在组织流程和外部影响因素等诸多方面结合在一起,基于AHP层次分析法和模糊综合评价法构建中国渔政管理指挥系统管理信息化绩效评价模型和多层次、多维度的评价指标体系,实现对中国渔政管理指挥系统管理信息化绩效的客观评价。通过对管理信息化绩效评价的研究,将为渔业管理部门提供系统实用的信息化评价方法和工具,帮助渔业管理部门明确在信息化需求和实施绩效方面的优势和薄弱环节,便于管理决策层及时掌握当前的信息化实施状态。 相似文献
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基于SD和模糊综合评价的土地整治项目社会影响评价 总被引:1,自引:1,他引:1
利用系统动力学的因果回路图分析土地整治的社会影响,运用层次分析法和模糊综合评价方法评估土地整治典型项目的社会影响程度。通过典型案例分析,该项目社会影响成功度综合评价结果为“基本成功”,其中“社会效率”成功度最高,“社会公平”次之,“可持续发展”成功度最低。运用系统动力学的理论对土地整治的社会影响的影响因素和传导途径进行解析,通过层次分析法和模糊综合评价法可对相关社会影响进行定量评估,研究成果可为土地整治项目的社会影响评价工作提供借鉴和参考。 相似文献
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As the research objective changing from a small simple system to a large complex one, traditional reliability theory can not adapt to the requirement of the great transformation. Based on the specialty of continuous process industry, the necessity and urgency to study the reliability of this kind of system is stated out. The research structural model of the reliability of complex continuous industries is presented also which involved in the reliability of human, network, software and devices. 相似文献