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991.
This paper introduces a dilatancy-based analytical model of the response of an axially loaded concrete cylinder, confined with a fiber-reinforced polymer (FRP) composite jacket. Model construction is based on the experimentally based observation that the relation between axial secant stiffness and the lateral (dilatancy) strain is effectively unique for cylinders with the same unconfined concrete strength, although the confinement levels may differ. Model development incorporates strength degradation of the concrete with dilatancy (lateral dilation); this feature allows one to demonstrate that the performance of FRP-confined concrete is consistent with the strength envelope obtained from triaxial tests. Model validation is accomplished by comparisons with existing test database and the new results on large-scale concrete cylinders. The results of the validation reveal good agreement with key response functions and parameters. The present study illustrates basic constitutive equations to model FRP-confined concrete in a more rational manner. 相似文献
992.
针对基于无线定位的交通信息采集中地图匹配问题,提出一种新的地图匹配算法,算法提取连续多个位置点的瞬时位置、方向和相邻时刻的运动距离构成具有三个特征变量的子时间序列,并用DTW来进行车行轨迹与候选路段的相似性测量,然后利用模糊偏序关系得到相似性的综合评估,将与移动台运动轨迹最相似的路段作为匹配点所在路段。实验结果证明了算法的有效性。 相似文献
993.
994.
文中分析了复合材料单层板的弹性主方向及非弹性主方向的弹性特性,进而分析了一般层合板的弹性特性及多层壳的弹性特性,以及导得具有普遍性的多层壳的稳定方程. 相似文献
995.
从歧口凹陷地质构造样式分析入手,结合构造动力学机制,探讨其对输导体系和储集体系的影响,进而影响油气成藏。结果表明:歧口凹陷古近系北西—南东方向多次凹复式箕状断陷结构和南北方向歧口主凹双断复式地堑结构,主要受沧东伸展断裂系统和歧口伸展断裂系统的控制,在平面上形成了多凸多凹、凹隆相间的构造古地貌格局,为岩性油气藏的形成创造了有利空间;歧口凹陷构造样式控藏影响,体现为:在油气运移时,主干断层控制油藏形成,次级断层改造油气分布,形成优势输导体系;在油气聚集时,有利储集相带发育,构造坡折带发育,有利圈闭发育。结合前人对油气成藏模式的研究,提出4种成藏模式的认识,即:陡坡带成藏模式、缓坡带成藏模式、断阶带近源成藏模式、盆内坡折带成藏模式。优选了勘探目标区,经钻探实例验证,取得良好效果。 相似文献
996.
针对大型电力系统安全约束最优潮流(SCOPF)问题具有的计算规模庞大、求解困难的特点,提出了基于潮流转移关系的SCOPF实用模型及故障态约束缩减方法。首先通过预想故障分析建立故障前后的有功潮流转移关系,将故障态支路有功潮流描述为基态支路有功潮流的函数,从而将故障态支路有功潮流约束描述为基态支路有功潮流的线性不等式约束;然后通过对并联线路或并列主变压器进行分组,利用组内支路的有功潮流分布关系减少需监视的支路规模;最后利用设备短时通流能力明显大于其长期通流能力的特征对故障态支路潮流约束进行过滤,以尽可能减小SCOPF问题的计算规模。IEEE 14节点测试系统和华东电网的仿真分析验证了所提模型及约束缩减方法的正确性和有效性。 相似文献
997.
An adaptive consensus model based on fuzzy information granulation (fuzzy IG) is presented for group consensus decision-making problems with multiplicative linguistic preference relations (MLPRs). Firstly, a granular representation of linguistic terms is concerned with the triangular fuzzy formation of a family of information granules over given Analytical Hierarchy Process (AHP) numerical scales. On this basis, the individual consistency and group consensus measure indices using fuzzy granulation technique are constructed, respectively. Then, the optimal cut-off points of fuzzy information granules are obtained by establishing a multi-objective optimization model together with a multi-objective particle swarm optimization (MOPSO) algorithm. A novel group consensus decision-making approach where consensus reaching process (CRP) is achieved by adaptively adjusting individual preferences through the optimization of the cut-off points is proposed. After conflict elimination, the obtained group preference gives the ranking of the alternatives. Finally, a real emergency decision-making case for liquid ammonia leak is given to illustrate the application steps of the proposed method and comparative analysis with the existing GDM methods. Comparative results demonstrate that the proposed method has some advantages in aspects of avoiding information loss or distortion and improving consensus performance. 相似文献
998.
《电子学报:英文版》2017,(5):942-946
There are representative models for spatial topological relations of Region connection calculus and intersections model.The purpose of this paper is to study the topological relations of multiple simple regions.In this paper,the 4-intersection matrix model is extended into a 2n-intersection representative function model to represent the spatial relations of multiple simple regions.The exclusiveness and the completeness of these topological relations are proved.Moreover,this paper also gives detailed discussion on the properties and applications of this model from a special and new perspective.And the topological relations among three simple regions in this paper are applied to forecast the impact of typhoon on the specified target areas.Compared with the extended 4-intersection model,8-intersection cube model is more elaborate in representing the topological relations among the three simple regions. 相似文献
999.
Niu Xinwen Ding Han Xiong YoulunSchool of Mechanical Science Engineering Huazhong University of Science TechnologyWuhan China 《机械工程学报(英文版)》2002,15(3):193-198
An integrated approach to generation of precedence relations and precedence graphs for assembly sequence planning is presented, which contains more assembly flexibility. The approach involves two stages. Based on the assembly model, the components in the assembly can be divided into partially constrained components and completely constrained components in the first stage, and then geometric precedence relation for every component is generated automatically. According to the result of the first stage, the second stage determines and constructs all precedence graphs. The algorithms of these two stages proposed are verified by two assembly examples. 相似文献
1000.
In the last decade, skyline queries have gained much attention and are proved to be valuable for multi-criteria decisions. Based on the concept of Pareto dominance, they return the non-dominated points, called the skyline points. In practice, it may happen that the skyline only contains a small number of points which could be insufficient for the user needs. In this paper, we discuss two fuzzy-set-based approaches to enriching the small skyline with particular points that could serve the decision makers’ needs. The basic idea consists in identifying the most interesting points among the non-skyline ones. On the one hand, we introduce a novel fuzzy dominance relationship which makes more demanding the dominance between the points of interest. So, much points would be considered as incomparable and then as elements of the new relaxed skyline. On the other hand, we leverage an appropriate fuzzy closeness relation to retrieve non skyline points that are fuzzily close to some skyline points. Furthermore, we develop efficient algorithms to compute the relaxed variants of skyline. Extensive experiments are conducted to demonstrate the effectiveness of our approaches and analyze the performance of the proposed algorithms. A comparative study between the approaches presented is made as well. 相似文献