全文获取类型
收费全文 | 148篇 |
免费 | 1篇 |
国内免费 | 4篇 |
专业分类
化学 | 4篇 |
数学 | 146篇 |
物理学 | 3篇 |
出版年
2023年 | 2篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 9篇 |
2013年 | 3篇 |
2012年 | 10篇 |
2011年 | 6篇 |
2010年 | 9篇 |
2009年 | 17篇 |
2008年 | 13篇 |
2007年 | 13篇 |
2006年 | 6篇 |
2005年 | 6篇 |
2004年 | 3篇 |
2003年 | 7篇 |
2002年 | 3篇 |
2001年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1983年 | 3篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1978年 | 2篇 |
排序方式: 共有153条查询结果,搜索用时 0 毫秒
51.
基于理想解法的公司债券财务状况评价 总被引:4,自引:0,他引:4
本文详细介绍了如何基于理想解法建立公司债券财务状况的评价模型,并通过指标数据进行了实证分析,得到了比较满意的评价结果。 相似文献
52.
Based on the ranking methodology of PROMETHEE, a new sorting method (ℱlow
ort) is proposed for assigning actions to completely ordered categories defined either by limiting profiles or by central
profiles. The ℱlow
ort assignment rules are based on the relative position of an action with respect to the reference profiles, in terms of the
incoming, leaving, and/or net flows. For a better understanding of the issues involved, a graphical representation is given.
An explicit relationship between the assignments obtained when working either with limiting or central profiles is formalized.
Finally, an empirical comparison with Electre-Tri is made to compare the resulting assignments.
相似文献
53.
Didier Dubois 《Fuzzy Sets and Systems》2011,184(1):3-28
We try to provide a tentative assessment of the role of fuzzy sets in decision analysis. We discuss membership functions, aggregation operations, linguistic variables, fuzzy intervals and the valued preference relations they induce. The importance of the notion of bipolarity and the potential of qualitative evaluation methods are also pointed out. We take a critical standpoint on the state-of-the-art, in order to highlight the actual achievements and question what is often considered debatable by decision scientists observing the fuzzy decision analysis literature. 相似文献
54.
In marketing research the measurement of individual preferences and assessment of utility functions have long traditions. Conjoint analysis, and particularly choice-based conjoint analysis (CBC), is frequently employed for such measurement. The world today appears increasingly customer or user oriented wherefore research intensity in conjoint analysis is rapidly increasing in various fields, OR/MS being no exception. Although several optimization based approaches have been suggested since the introduction of the Hierarchical Bayes (HB) method for estimating CBC utility functions, recent comparisons indicate that challenging HB is hard. Based on likelihood maximization we propose a method called LM and compare its performance with HB using twelve field data sets. Performance comparisons are based on holdout validation, i.e. predictive performance. Average performance of LM indicates an improvement over HB and the difference is statistically significant. We also use simulation based data sets to compare the performance for parameter recovery. In terms of both predictive performance and RMSE a smaller number of questions in CBC appears to favor LM over HB. 相似文献
55.
In this paper, we give a classification of (finite or countable) ?0‐categorical coloured linear orders, generalizing Rosenstein's characterization of ?0‐categorical linear orderings. We show that they can all be built from coloured singletons by concatenation and ?n‐combinations (for n ≥ 1). We give a method using coding trees to describe all structures in our list (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
56.
We present a new methodology for simultaneously assessing competitive market structure and deriving market segments. A hierarchical or ultrametric tree representation is estimated in a maximum likelihood framework from collected paired-comparison choice data. The derived tree portrays both brands and consumers/households/segments as terminal nodes, where the ‘closer’ a brand is to a particular consumer/household/segment in the tree, the higher the predicted probability of that consumer/household/segment choosing that particular brand. This paper initially presents an introduction to the problem of market structure assessment. We review the extensive marketing literature on market structure and survey several competing methodologies. The proposed stochastic ultrametric tree unfolding methodology is technically described and several program options are indicated. An illustration of the proposed methodology is presented with respect to paired comparison choice data collected from a convenience sample involving the over-the-counter analgesics market. Finally, several areas for future research are identified. 相似文献
57.
模糊偏好关系在群决策中得到了广泛研究,针对犹豫直觉模糊集既能反映决策者偏好和非偏好的信息,又能描述其犹豫心理的特点,提出了犹豫直觉模糊偏好关系及其积性一致性的定义。为了修复不一致的犹豫直觉模糊偏好关系,先构建积性一致性指标,然后提出两种修复方法。最后,将犹豫直觉模糊偏好关系应用到群决策中,通过实例和比较说明了两种修复方法的有效性和合理性。 相似文献
58.
R. Beauwens 《Numerical Linear Algebra with Applications》1994,1(1):3-17
Preconditioned iterative methods are widely used to solve linear systems such as those arising from the finite element formulation of boundary value problems and approximate factorizations are widely used as preconditioners. The ordering of the unknowns is therefore an important issue because it has a strong influence on the convergence behaviour of the iteration method while it is also a decisive aspect for their parallel implementation. Consistent orderings are attractive for parallel implementations and it has been shown that some subclasses of these orderings also enhance the convergence behaviour of the associated iteration methods. This has in particular been shown for the so-called S/P consistent orderings. A wider definition of this class of orderings has recently been proposed and we investigate here how approximate factorizations should be implemented when using such more general orderings (still called S/P consistent) in order to keep their expected high convergence properties. A simple practical conclusion is suggested, supported by both theoretical and numerical arguments. 相似文献
59.
Motivated by applications in reliability theory, we define a preordering (X
1, ...,X
n)
(Y
1 ...,Y
n) of nonnegative random vectors by requiring thek-th order statistic ofa
1
X
1,..., a
n
X
n to be stochastically smaller than thek-th order statistic ofa
1
Y
1, ...,a
n
Y
n for all choices ofa
i
>0,i=1, 2, ...,n. We identify a class of functionsM
k, n such that
if and only ifE(X)E(Y) for allM
k,n. Some preservation results related to the ordering
are obtained. Some applications of the results in reliability theory are given.Supported by the Air Force Office of Scientific Research, U.S.A.F., under Grant AFOSR-84-0205. 相似文献
60.
Bart Smeulders Yves Crama Frits C.R. Spieksma 《European Journal of Operational Research》2019,272(3):803-815
Revealed preference theory is a domain within economics that studies rationalizability of behavior by (certain types of) utility functions. Given observed behavior in the form of choice data, testing whether certain conditions are satisfied gives rise to a variety of computational problems that can be analyzed using operations research techniques. In this survey, we provide an overview of these problems, their theoretical complexity, and available algorithms for tackling them. We focus on consumer choice settings, in particular individual choice, collective choice and stochastic choice settings. 相似文献