全文获取类型
收费全文 | 212篇 |
免费 | 19篇 |
国内免费 | 7篇 |
专业分类
化学 | 2篇 |
力学 | 2篇 |
综合类 | 4篇 |
数学 | 209篇 |
物理学 | 9篇 |
无线电 | 12篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 5篇 |
2020年 | 11篇 |
2019年 | 14篇 |
2018年 | 9篇 |
2017年 | 6篇 |
2016年 | 4篇 |
2015年 | 6篇 |
2014年 | 5篇 |
2013年 | 15篇 |
2012年 | 8篇 |
2011年 | 15篇 |
2010年 | 6篇 |
2009年 | 14篇 |
2008年 | 14篇 |
2007年 | 11篇 |
2006年 | 9篇 |
2005年 | 7篇 |
2004年 | 10篇 |
2003年 | 11篇 |
2002年 | 9篇 |
2001年 | 7篇 |
2000年 | 6篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1973年 | 1篇 |
排序方式: 共有238条查询结果,搜索用时 15 毫秒
231.
高效地找出所有的频繁项集是关联规则挖掘中的核心问题。通过对已有的基于矩阵的频繁项集挖掘算法的研究,提出一种基于团的频繁项集快速生成算法。该算法采用关联图存储频繁两项集信息,找关联图中团,逐步减少团中项来搜索所有最大频繁项集,并且其扫描数据库仅需一次。通过使用标准数据集进行验证测试并与其他算法进行比较,实验结果表明,该算法具有较快的挖掘速度。 相似文献
232.
Serkan Eryilmaz Omer L. Gebizlioglu Fatih Tank 《Insurance: Mathematics and Economics》2011,49(3):496-500
Large claims in an actuarial risk process are of special importance for the actuarial decision making about several issues like pricing of risks, determination of retention treaties and capital requirements for solvency. This paper presents a model about claim occurrences in an insurance portfolio that exceed the largest claim of another portfolio providing the same sort of insurance coverages. Two cases are taken into consideration: independent and identically distributed claims and exchangeable dependent claims in each of the portfolios. Copulas are used to model the dependence situations. Several theorems and examples are presented for the distributional properties and expected values of the critical quantities under concern. 相似文献
233.
Andrew D. King 《Journal of Graph Theory》2011,67(4):300-305
Rabern recently proved that any graph with contains a stable set meeting all maximum cliques. We strengthen this result, proving that such a stable set exists for any graph with . This is tight, i.e. the inequality in the statement must be strict. The proof relies on finding an independent transversal in a graph partitioned into vertex sets of unequal size. © 2010 Wiley Periodicals, Inc. J Graph Theory 67:300‐305, 2011 相似文献
234.
235.
Four NP-hard optimization problems on graphs are studied: The vertex separator problem, the edge separator problem, the maximum clique problem, and the maximum independent set problem. We show that the vertex separator problem is equivalent to a continuous bilinear quadratic program. This continuous formulation is compared to known continuous quadratic programming formulations for the edge separator problem, the maximum clique problem, and the maximum independent set problem. All of these formulations, when expressed as maximization problems, are shown to follow from the convexity properties of the objective function along the edges of the feasible set. An algorithm is given which exploits the continuous formulation of the vertex separator problem to quickly compute approximate separators. Computational results are given. 相似文献
236.
A strong clique in a graph is a clique intersecting every maximal independent set. We study the computational complexity of six algorithmic decision problems related to strong cliques in graphs and almost completely determine their complexity in the classes of chordal graphs, weakly chordal graphs, line graphs and their complements, and graphs of maximum degree at most three. Our results rely on connections with matchings and relate to several graph properties studied in the literature, including well-covered graphs, localizable graphs, and general partition graphs. 相似文献
237.
YANG Xu-Hua WANG Bo WANG Wan-Liang SUN You-Xian 《理论物理通讯》2008,50(11):1249-1254
On the basis of investigating the statistical data of bus transport networks of three big cities in China, we propose that each bus route is a clique (maximal complete subgraph) and a bus transport network (BTN) consists of a lot of cliques, which intensively connect and overlap with each other. We study the network properties, which include the degree distribution, multiple edges' overlapping time distribution, distribution of the overlap size between any two overlapping cliques, distribution of the number of cliques that a node belongs to. Naturally, the cliques also constitute a network, with the overlapping nodes being their multiple links. We also research its network properties such as degree distribution, clustering, average path length, and so on. We propose that a BTN has the properties of random clique increment and random overlapping clique, at the same time, a BTN is a small-world network with highly clique-clustered and highly clique-overlapped. Finally, we introduce a BTN evolution model, whose simulation results agree well with the statistical laws that emerge in real BTNs. 相似文献
238.
Let GP be the m-Paley graph defined on the finite field with order . We study eigenfunctions and maximal cliques in generalised Paley graphs GP , where . In particular, we explicitly construct maximal cliques of size or in GP , and show the weight-distribution bound on the cardinality of the support of an eigenfunction is tight for the smallest eigenvalue of GP . These new results extend the work of Baker et al. and Goryainov et al. on Paley graphs of square order. We also study the stability of the Erdős-Ko-Rado theorem for GP (first proved by Sziklai). 相似文献