钢筋混凝土桥梁的耐久性评估

为解决现阶段钢筋混凝土桥梁耐久性评估中所存在的步骤粗糙、程序简单、主观性较强等问题,基于我国《公路桥梁技术状况评定标准》、《公路桥涵养护规范》,确定出评价指标体系、分类等级界限及全桥不同等级下的结构综合性病况;并利用层次分析法、熵权理论确定各指标的主、客观权重系数,依据组合权重理论确定各因素的综合权重向量集,采用模糊学理论中的岭形隶属函数构造模糊评价矩阵,按照由底层向顶层逐层评价的顺序,构建了三层次三环节的桥梁耐久性模糊评估模型;然后根据最大隶属度原则确定桥梁耐久性状态等级,并为不同耐久性状态等级的钢筋混凝土桥梁提供了具体的解决整修措施;最后,结合实例检验该评价方法的科学性与合理性。结果表明,以3组检测数据样本为依据,评估所得实例桥整体状态均为Ⅱ级,与现场实际检测所得的评估结果一致。组合权重理论既能结合专家经验又能考虑现场实际情况,而模糊学理论能够与工程应用进行较强的结合,以此能减少主观评估、片面化、评价过于精简等问题;并且组合权重-模糊学理论综合评价方法思路清晰、客观性强、计算简单、评价结果能够详细给出不同结构部位的耐久状态。

Multi-objectives fuzzy optimization model for ship form demonstration based on information entropy

Selecting optimization ship form scheme is an important content in the process of concept design of ship. Multi-objective fuzzy decision-making model for ship form demonstration is set up according to the fuzzy pattern-recognition theory. Weight coefficients of each target of ship form scheme are determined by information entropy and individual subjective partiality. This model is used to select the optimal ship form scheme, the example shows that the model is exact and the resuh is credible. It can provide a reference for choosing the optimization scheme of ship form.

Optimal design of structural parameters for shield cutterhead based on fuzzy mathematics and multi-objective genetic algorithm

In order to improve the strength and stiffness of shield cutterhead, the method of fuzzy mathematics theory in combination with the finite element analysis is adopted. An optimal design model of structural parameters for shield cutterhead is formulated,based on the complex engineering technical requirements. In the model, as the objective function of the model is a composite function of the strength and stiffness, the response surface method is applied to formulate the approximate function of objective function in order to reduce the solution scale of optimal problem. A multi-objective genetic algorithm is used to solve the cutterhead structure design problem and the change rule of the stress-strain with various structural parameters as well as their optimal values were researched under specific geological conditions. The results show that compared with original cutterhead structure scheme, the obtained optimal scheme of the cutterhead structure can greatly improve the strength and stiffness of the cutterhead, which can be seen from the reduction of its maximum equivalent stress by 21.2%, that of its maximum deformation by 0.75%, and that of its mass by 1.04%.

Research on the fully fuzzy time-cost trade-off based on genetic algorithms

It is very difficult to estimate exact values of time and cost of an activity in project scheduling process because many uncertain factors, such as weather, productivity level, human factors etc. , dynamically affect them during project implementation process. A GAs-based fully fuzzy optimal time-cost trade-off model is presented based on fuzzy sets and genetic algorithms (GAs). In tihs model all parameters and variables are characteristics by fuzzy numbers. And then GAs is adopted to search for the optimal solution to this model. The method solves the time-cost trade-off problems under an uncertain environment and is proved practicable through a giving example in ship building scheduling.

On the Model Properties of BCK Algebras

This paper is devoted to the study of the logical properties of BCK algebras. For formalized BCK algebra theory T, it is proved that T is preserved under submodels and unions of chains; T is neither complete nor model complete, and hence there exist no built-in Skolem function. Moreover, the ultraproduct BCK algebras and the fuzzy ultraproduct of fuzzy subsets of BCK algebras were proposed by using the concept of ultrafilters with corresponding properties of fuzzy ideals discussed.

Effect of the computer fuzzy control on coal seam injection

To enhance the technology and efficiency of strata injection is a problem to be solved urgently. Because of effected by the rough and poor production conditions of mining and the changeable bearing condition of strata, the technological process of injection can not be controlled automatically.The fuzzy controlling technology of the coal strata injection is applied. This is the good way to ensure the effectiveness and efficiency of coal strata injection and to solve the current problems of production and safety in mining industry.

Agents and Lattice-valued Logic

In fuzzy set theory, instead of the underlying membership set being a two-valued set it is a multi-valued set that generally has the structure of a lattice L with a minimal element O and the maximal element I. Furthermore if ∧, ∨, → and ┐ are defined in the set L, then we can use these operations to define, as in the ordinary set theory, operations on fuzzy subsets. In this paper we give a model of the Lattice-Valued Logic with set of agents. Any agents know the logic value of a sentence p. The logic value is compatible with all of the accessible conceptual models or worlds of p inside the agent. Agent can be rational or irrational in the use of the logic operation. Every agent of n agents can have the same set of conceptual models for p and know the same logic for p in this case the agents form a consistent group of agents. When agents have different conceptual models for p, different subgroup of agents know different logic value for p. In this case the n agents are inconsistent in the expression of the logic value for p. The valuation structure of set of agents can be used as a semantic model for the Lattice-valued Logic and fuzzy logic.

The Application of Improved Fuzzy Comprehensive Evaluation method in Practice Teaching Quality Evaluation System

According to the theory of fuzzy mathematics, Fuzzy comprehensive evaluation method of the original algorithm is improved, and reduced the possibility loss of the original evaluation data. The improved algorithm is applied in the practice teaching quality evaluation system, and improved the practice teaching quality evaluation results and the accuracy of visual, and promote the teaching management scientific, standardized and institutionalized. In order to establish incentive mechanism, it can bring a positive role to improve teaching quality.

Strong Limit Theorems for Arbitrary Fuzzy Stochastic Sequences

Based on fuzzy random variables, the concept of fuzzy stochastic sequences is defined. Strong limit theorems for fuzzy stochastic sequences are established. Some known results in non-fuzzy stochastic sequences are extended. In order to prove results of this paper, the notion of fuzzy martingale difference sequences is also introduced.

Investigation on Fuzzy in English Literature Teaching

This thesis studies the concept and research background of filzziness and fuzzy theory, then committing further enumeration and analysis of the application of fuzzy theory in the fields of linguistics and literature. On this basis, the effectiveness and rationalization of the fuzzy theory＇s application in the English literature teaching were confirmed from many aspects. Among them, it is mainly investigated and analyzed from the objective factors and subjective factors. Subjective aspects mainly contain students＇ different cognitive ability, and the diversity existed in teachers＇ teaching and guiding methods. Objective aspects mainly include that the literature language and literature thoughts itself have the unique ambiguity. Finally, in summing up the investigation results the author put forward the essence of English literature teaching activity and put forward the methods to improve English literature teaching.