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排序方式: 共有1205条查询结果,搜索用时 15 毫秒
1.
作为直觉模糊集的推广形式,毕达哥拉斯模糊数能更好地刻画现实中的不确定性,此外在某些问题上,方案的属性之间往往具有优先关系,针对此类信息的集成问题,将毕达哥拉斯模糊数与优先集成算子相结合,提出了毕达哥拉斯模糊优先集成算子,包括毕达哥拉斯模糊优先加权平均算子和毕达哥拉斯模糊优先加权几何算子,并讨论了这些算子的性质。在此基础上,提出了毕达哥拉斯模糊优先集成算子的多属性决策方法,最后将其应用于国内四家航空公司服务质量评价中,说明了该算子的有效性和可行性。  相似文献   
2.
Mathematical problems and their solutions from the fourth International Students’ Olympiad in cryptography (NSUCRYPTO-2017) are presented. We consider problems related to attacks on ciphers and hash functions, cryptographic Boolean functions, linear branch numbers, addition chains, and error correction codes, among others. We discuss several open problems involving the algebraic structures of cryptographic functions, useful proof-of-work algorithms, the Boolean hidden shift problem, and quantum computing.  相似文献   
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This paper introduces the best–worst method to solve multi-attribute decision-making (MADM) problems in the fuzzy environment. In the proposed method, there is no need to do all the possible pairwise comparisons. In other words, only reference comparisons should be done. Reference comparisons consist of assessing the relative fuzzy preference of the best criterion (alternative) over others and all the criteria (alternatives) over the worst one. Afterward, a fully fuzzy linear mathematical model will be formulated and solved to determine the weight of the criteria. The same action will be performed to find the score of alternatives. This method has some interesting and valuable characteristics: (a) less required data for pairwise comparison, (b) high ability to provide a reliable solution, (c) it is an autonomous method along with its high capability to accompany another method. To evaluate the performance, it is compared with another fuzzy MADM method in an example. Furthermore, we apply this method for the maintenance evaluation of hospitals in Bojnord. The computational study confirms the high efficiency and satisfactory performance of the method, and results are validated by a low consistency ratio. Furthermore, the suggested methodology outperforms fuzzy AHP and well verified in the test instance.  相似文献   
6.
袁莉芬  熊波 《仪器仪表学报》2015,36(7):1598-1604
观测矩阵在信号压缩感知中十分重要,直接决定信号的重构质量。为保证信号的重构精度,要求观测矩阵具有很强的随机性,但随机矩阵硬件实现非常困难;确定性观测矩阵易于实现,但其重构精度不足。针对观测矩阵对随机性与确定性的双重要求,提出利用超素数产生超长周期的伪随机序列,解决确定性观测矩阵对随机性的要求;结合托普利兹观测矩阵的确定性结构特征,得到一种改进的托普利兹观测矩阵。实验仿真表明:改进的托普利兹观测矩阵与高斯随机观测矩阵和常用托普利兹观测矩阵相比,其信号重构精度得到了很好的改善,且易于硬件实现。  相似文献   
7.
The number of receptors expressed by cells plays an important role in controlling cell signaling events, thus determining its behaviour, state and fate. Current methods of quantifying receptors on cells are either laborious or do not maintain the cells in their native form. Here, a method integrating highly sensitive bioluminescence, high precision microfluidics and small footprint of lensfree optics is developed to quantify cell surface receptors. This method is safe to use, less laborious, and faster than the conventional radiolabelling and near field scanning methods. It is also more sensitive than fluorescence based assays and is ideal for high throughput screening. In quantifying β1 adrenergic receptors expressed on the surface of H9c2 cardiomyocytes, this method yields receptor numbers from 3.12 × 105 to 9.36 × 105 receptors/cell which are comparable with current methods. This can serve as a very good platform for rapid quantification of receptor numbers in ligand/drug binding and receptor characterization studies, which is an important part of pharmaceutical and biological research.  相似文献   
8.
The linguistic computing model based on discrete fuzzy numbers has some good properties compared with other existing models and should be further studied, which has been proved by some researchers. However, the research of group consensus with this linguistic model is insufficient, given that group consensus is an important issue in group decision making. Therefore, this paper would concentrate on this subject. It includes two main issues: research on consensus measure and research on the method for improving group consensus in group decision making based on this linguistic computing model. For research on the consensus measure, this paper first studies on the aggregation method for discrete fuzzy numbers. Then, the index of measuring group consensus is determined. For research on improving the group consensus, considering the characteristics of discrete fuzzy numbers, we present an algorithm to improve group consensus. In addition, an illustrative example of a decision-making problem about investment is stated to show the whole solving process. It also illustrates the feasibility, rationality and validity of all the proposed methods. Finally, the comparisons between some proposals and existing studies are made, which helps point out the advantages of the proposed methods.  相似文献   
9.
In this paper, we extend the Bonferroni mean (BM) operator with the picture fuzzy numbers (PFNs) to propose novel picture fuzzy aggregation operators and demonstrate their application to multicriteria decision making (MCDM). On the basis of the algebraic operational rules of PFNs and BM, we introduce some aggregation operators: the picture fuzzy Bonferroni mean, the picture fuzzy normalized weighted Bonferroni mean, and the picture fuzzy ordered weighted Bonferroni mean. Then, a new picture fuzzy MCDM method is proposed with the help of the proposed operators. Lastly, a practical application of proposed model is given to verify the developed model and related results of the proposed model is compared with the results of the existing models to indicate its applicability.  相似文献   
10.
在清晰数的四则运算的基础上,给出了清晰数心的概念,继而定义了清晰数的大小关系,这样就可以进行清晰数的比较,为以后的研究奠定了基础。  相似文献   
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