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61.
本文对带有付费过程$A_t$的保险公司在金融市场$(S_t,Q_t,B_t)$上通过购买股票$S_t$、兑换外币$Q_t$以及购买无风险资产$B_t$的投资过程而采取的最优投资策略, 使保险公司所面临的风险最小进行探讨. 利用Galtchouk-Kunita-Watanabe分解定理将风险表达式重新表达, 从而找到保险公司所能采取的风险最小的最优对冲策略. 文中举出一个具有现实性意义的例子将文章的重要结论加以应用, 使本文更具有应用价值.  相似文献   
62.
The selection of a monitoring network is formulated as a decision problem whose solutions would then be optimal. The theory is applied where the underlying field has a multivariate normal probability structure.  相似文献   
63.
The procedure UFAP is presented which allows a decision maker to interactively assess his von Neumann/Morgenstern single attribute utility function. UFAP puts special emphasis on potential biases in the assessment process. In the first part of the procedure three different assessment methods are used to derive ranges for the utility function. Using different methods enables us to point out a possible bias in the elicitation process. In the second part a consistent class of utility functions is derived based on the ranges assessed in the first part. In case inconsistencies between methods arise the decision maker has to reconsider selected preference statements previously given.  相似文献   
64.
A problem which has been constantly emphasized is the creation of criteria adequate to characterize the complexity of ecological analysis. The objective of the present paper is to demonstrate the capabilities of multiattribute utility theory in difficult-to-formalize problems. The multiattribute utility and the proposed algorithms provide a logically and operationally tested method which includes value in complex ecological problems. The results obtained and the constructed utility functions should be accepted as an iterative stage in real investigations, rather than as complete research that offer a final decision. The value estimations of the decision maker are the basis for interest in a given ecological problem. But they are often not explicitly or consistently addressed in the real investigations. The proposed methods account for otherwise uninterpretable information. The constructed value function can be used for automatic computer control and monitoring of anaerobic waste water digestion, which could reveal a new potential from the practical point of view.  相似文献   
65.
66.
This paper examines the situation where a risk-averse insured determines the optimal amount of deductible (or stop-loss) insurance. The insurer uses two different premium principles, the expected value principle and the exponential principle. The insured has an exponential utility function. Specific numerical results are obtained for the optimal stop-loss limit in the case of a group life insurance plan. The exact results are contrasted with those obtained by using the normal approximation instead of the exact distribution of aggregate claims.  相似文献   
67.
This paper describes the use of fuzzy set theory in goal programming (GP) problems. In particular, it is demonstrated how fuzzy or imprecise aspirations of the decision maker (DM) can be quantified through the use of piecewise linear and continuous functions. Models are then presented for the use of fuzzy goal programming with preemptive priorities, with Archimedean weights, and with the maximization of the membership function corresponding to the minimum goal. Examples are also provided.  相似文献   
68.
Many problems faced by decision makers are characterized by a multistage decision process with uncertainty about the future and some decisions constrained to take on values of either zero or one (for example, either open a facility at a location or do not open it). Although some mathematical theory exists concerning such problems, no general-purpose algorithms have been available to address them. In this article, we introduce the first implementation of general purpose methods for finding good solutions to multistage, stochastic mixed-integer (0, 1) programming problems. The solution method makes use of Rockafellar and Wets' progressive hedging algorithm that averages solutions rather than data. Solutions to the induced quadratic (0,1) mixed-integer subproblems are obtained using a tabu search algorithm. We introduce the notion of integer convergence for progressive hedging. Computational experiments verify that the method is effective. The software that we have developed reads standard (SMPS) data files.  相似文献   
69.
0Intr0ducti0nAferEpsteinandZin(1989,199l)andWeil(1990),n0n-expectedutilitypreferences0ftenaPpwinassetpricingthe0ryinsteadofc0nventi0naltime-allitive,expectedutilityAnattrec-tivefeature0fthisgeneralisedspecificationisthatintertemp0ralsubStitutinnandriskaversioucanbepartiallydisentangled,incontr8ttothec0nventi0nalcaseofanadditiveandhomthgeneousVonNeumann-MorgellsternintertemPoralutilityfuncti0n,inwhichtheelasticityofsub8titutionandthec0efficielltofrelativeriskaversionarec0nstrainedtoberecipr0…  相似文献   
70.
Classical portfolio selection problems that optimise expected utility can usually not be solved in closed form. It is natural to approximate the utility function, and we investigate the accuracy of this approximation when using Taylor polynomials. In the important case of a Merton market and power utility we show analytically that increasing the order of the polynomial does not necessarily improve the approximation of the expected utility. The proofs use methods from the theory of parabolic second-order partial differential equations. All results are illustrated by numerical examples.  相似文献   
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