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排序方式: 共有342条查询结果,搜索用时 15 毫秒
51.
首先建立了针对高校技术交易评价的指标体系.结合所要研究的问题,说明了如何使用熵值法对评价指标进行赋权,并通过灰色关联度方法进行评价.然后,应用建立的评价方法结合A高校2006-2013年间技术交易的统计数据,对A高校技术交易的总体情况进行了客观评价,为高校技术交易管理提供了有价值的参考. 相似文献
52.
Emmanuel Lepinette Tuan Tran 《Stochastics An International Journal of Probability and Stochastic Processes》2016,88(3):437-459
Financial market models defined by a liquidation value process generalize the conic models of Schachermayer and Kabanov where the transaction costs are proportional to the exchanged volumes of traded assets. The solvency set of all portfolio positions that can be liquidated without any debt is not necessary convex, e.g. in presence of proportional transaction costs and fixed costs. Therefore, the classical duality principle based on the Hahn–Banach separation theorem is not appropriate to characterize the prices super hedging a contingent claim. Using an alternative method based on the concepts of essential supremum and maximum, we provide a characterization of European and American contingent claim prices under the absence of arbitrage opportunity of the second kind. 相似文献
53.
This paper mainly concerns the numerical solution of a nonlinear parabolic double obstacle problem arising in a finite-horizon optimal investment problem with proportional transaction costs. The problem is initially posed in terms of an evolutive HJB equation with gradient constraints and the properties of the utility function allow to obtain the optimal investment solution from a nonlinear problem posed in one spatial variable. The proposed numerical methods mainly consist of a localization procedure to pose the problem on a bounded domain, a characteristics method for time discretization to deal with the large gradients of the solution, a Newton algorithm to solve the nonlinear term in the governing equation and a projected relaxation scheme to cope with the double obstacle (free boundary) feature. Moreover, piecewise linear Lagrange finite elements for spatial discretization are considered. Numerical results illustrate the performance of the set of numerical techniques by recovering all qualitative properties proved in Dai and Yi (2009) [6]. 相似文献
54.
In defined benefit pension plans, allowances are independent from the financial performance of the fund. And the sponsoring firm pays regularly contributions to limit deviations of fund assets from the mathematical reserve, necessary for covering the promised liabilities. This research paper proposes a method to optimize the timing and size of contributions, in a regime switching economy. The model takes into consideration important market frictions, like transactions costs, late payments and illiquidity. The problem is solved numerically using dynamic programming and impulse control techniques. Our approach is based on parallel grids, with trinomial links, discretizing the asset return in each economic regime. 相似文献
55.
信息技术的快速发展,使得闲置产能的分享逐渐成为生产领域重要的产能利用模式。为研究闲置产能分享时平台的最优定价问题,在平台向供给者收取交易费而对需求者不收费的条件下,首先,建立商业平台和公益平台的基础模型,并对两类平台进行分析和对比;然后,在基础模型之上构建以一定权重考虑其他参与者利益的平台X的定价模型,探讨权重对最优交易费、供需双方的数量以及平台最优利润的影响;最后,用数值例子验证文中重要定理以及权重对供需双方效用产生的影响。研究结果表明:(1)商业平台收取的最优交易费和获得的最优利润均高于公益平台;(2)考虑其他参与者利益的平台X收取的最优交易费和获得的最优利润、需求者(免费方)的数量和效用均随着权重的增加而增加,而供给者(被收费方)的数量及其效用则随着权重的增加而减少。研究结果为平台运营商和企业的行为决策提供理论参考依据。 相似文献
56.
刘正春 《数学的实践与认识》2004,34(6):32-37
基于 APT理论 ,在不允许卖空、并考虑交易成本的情况下 ,本文建立了多因素证券组合投资决策模型 ,然后利用遗传算法研究了模型的求解 相似文献
57.
In this paper we examine the Akian, Menaldi and Sulem (1996) model for the optimal management of a portfolio, when there are transaction costs which are equal to a fixed percentage of the amount transacted. We analyse this model in the realistic limit of small transaction costs. Although the full problem is a free boundary diffusion problem in as many dimensions as there are assets in the portfolio, we find explicit solutions for the optimal trading policy in this limit. This makes the solution for a realistically large number of assets a practical possibility. 相似文献
58.
59.
Luitgard A. M. Veraart 《Applied Mathematical Finance》2013,20(4):359-372
Abstract This paper is concerned with optimal market making in the foreign exchange market. The market maker's holdings in the different currencies are modelled as stochastic processes that are influenced by both the stochastic exchange rates and the stochastic customer buy and sell orders. The market maker can control their own bid and ask price quotes and, additionally, can buy and sell at other market participants' quotes. The resulting stochastic control problem consists of a controlled diffusion problem for the optimal quotes and a singular control problem for optimal trades at other market participants' quotes. A Markov chain approximation is used to derive optimal strategies. 相似文献
60.
可疑交易识别是打击洗钱犯罪所要面对的一项重要任务.为辅助反洗钱分析人员从海量金融交易信息中甄别客户异常交易,本文提出一种新的基于非线性马尔科夫随机过程、相空间重构和隐马尔科夫链的非线性随机方法,用于对金融交易时序进行建模拟合,然后应用鲁棒控制图对估计误差进行检验以发现异常.应用该算法对实际交易数据和仿真数据的分析验证了所提方法的有效性和可行性,可以被用于异常交易的监测. 相似文献