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51.
Efficient combination rule of Dezert-Smarandache theory 总被引:2,自引:0,他引:2
The Dezert-Smarandache theory (DSmT) is a useful method for dealing with uncertainty problems. It is more efficient in combining conflicting evidence. Therefore, it has been successfully applied in data fusion and object recognition. However, there exist shortcomings in its combination rule. An efficient combination rule is presented, that is, the evidence's conflicting probability is distributed to every proposition based on remaining the focal elements of conflict. Experiments show that the new combination rule improves the reliability and rationality of the combination results. Although evidences conflict another one highly, good combination results are also obtained. 相似文献
52.
In this paper, a new triangular element (Quasi-Carey element) is constructed by the idea of Specht element. It is shown that this Quasi-Carey element possesses a very special property, i.e., the consistency error is of order O(h^2), one order higher than its interpolation error when the exact solution belongs to H^3(Ω). However, the interpolation error and consistency error of Carey element are of order O(h). It seems that the above special property has never been seen for other triangular elements for the second order problems. 相似文献
53.
54.
LIANG Hanying 《系统科学与复杂性》2000,(2)
1. Introduction and Main ResultsSince the definition on complete convergence of real random variables was introduced by Hsuand Robbins[1], there have been extensive literature on the complete convergence of i.i.d. realvalued random variables, see Baum and Katz ([2]), Bat and Su ([3]). In 1989, Yul4] extendedsome results in Bat and Su ([3]) to real valued independent but not necessarily identicallydistributed case. The main purpose of this paper is to extend the results of Yu[4] to B-value… 相似文献
55.
THE DOMAIN DECOMPOSITION TECHNIQUES FOR THE FINITE ELEMENT PROBABILITY COMPUTATIONAL METHODS 总被引:2,自引:0,他引:2
LIU Xiaoqi 《系统科学与复杂性》2000,(2)
1. IntroductionWe have discussed probability computational methods of finite element methods in [1,2,3,4].Probability computational methods have many advalltages. The advantages are more obviousin three dimensions for finite element problems. In probability model, the time that the particlemoves from one place to the boundary of the domain and is absorbed by the boundary (whichis called the time of running up to the boundary for short) is only dependent on the averagedistance between the start… 相似文献
56.
YUAN Yirang 《系统科学与复杂性》2000,(3)
1.IntroductionThisarticlediscussestheenhanced0ilrecoverynumericalsimulationofthechemicalflood-ing(suchassurfactats,alcohol,polymers)c0mposed0f3-dimensional,multicomponent,muLtiphaseandincompressiblemixedfluids.Aftertheoilfieldiswaterfi0oded,thereisstillalargeamountofcrudeoilleftintheoildeposit.Thisamountofoil,boundedbycapillarypressure,cannotflow;or)asaresultofthedisadvantageousrateofflowbetweenthedisplacinganddisplacedphases,thevolumethattheinjectionfiowaffectsistoosmalltodrivethecrudeoil.By… 相似文献
57.
针对航空交流电源中旋转电枢式无刷交流同步发电机组的内部电磁场运行原理、瞬态运行特征及故障工况研究,传统解析法受前提条件限制不能进一步提高分析能力,而有限元法是分析电机的常用数值计算方法.多数文献只选择旋转磁极式主发电机进行了电磁分析.这里在忽略端部漏抗的前提下,提出用二维有限元法建立直流电流源激励的旋转电枢式交流励磁机瞬态电磁场耦合模型,推导了迭代方程组的教学表达式,利用离散化法解算得到交流励磁机的瞬态磁路和电路特性,通过对某型航空交流电源的交流励磁机的实例建模分析,验证了方法的正确性,对于研究交流电源中旋转电枢式结构的交流励磁机的瞬态电磁特性起到了重要的参考价值. 相似文献
58.
A low order nonconforming finite element is applied to the parabolic problem with anisotropic meshes. Both the semidiscrete and fully discrete forms are studied. Some superclose properties and superconvergence are obtained through some novel approaches and techniques. This research was supported by the National Natural Science Foundation of China under Grant No. 10671184. 相似文献
59.
Analysis of electrical performances of planar active phased array antennas with distorted array plane 总被引:1,自引:0,他引:1
The influence of the distorted plane of the active phased array antenna on the electromagnetic performance is of great significance to the research on and development of the high-performance antennas. On the bent and bowl-shape distortion, the model is established of the relationship between the electromagnetic performance and the position error of the radiated elements. The method is presented of analyzing the far-field pattern of the distorted rectangular active phased array antenna. The analysis results of a planar phased array antenna with different distortions grades prove the validity of the model. Therefore, by the method, the antenna designers may set the reasonable requirement on the structural tolerance in manufacturing antenna. 相似文献
60.