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891.
在政府推行补贴政策背景下,通过建立博弈模型研究了政府补贴、制造商和零售商的风险规避对绿色供应链定价策略、产品绿色度、供应链各方利润及整体利润的影响。研究表明:制造商或零售商单方面的风险规避对对方来说都是有利的,但不同的是,仅制造商风险规避时,产品绿色度、批发价格、零售价格及其自身利润都将下降,供应链整体利润则既存在上升也存在下降的情况,当仅零售商风险规避时,产品绿色度、供应链整体利润都将上升,批发价格、零售价格及其自身利润则既存在上升也存在下降的情况;政府增加补贴会在一定程度上加重制造商的风险规避对其自身利润及产品绿色度的损害作用,却会在一定程度上减弱零售商的风险规避对其自身利润的损害作用,并增强零售商的风险规避对产品绿色度的提升作用。  相似文献   
892.
杨希雅  石宝峰 《运筹与管理》2022,31(11):186-193
2018年以来中国债券市场违约规模攀升,累计违约金额超2900亿元。债券违约后的负面影响受到投资者、发行人乃至监管部门关注。本文以北京、上海、辽宁等八个辖区为例,选取2016~2019年债券违约及债券发行数据,通过构建违约事件对债券发行价格影响因素模型,分析了债券违约的区域传染效应。研究发现:债券违约引发的信用风险存在区域传染性,主要体现为债券发行前若发行人所属辖区存在违约事件将推升债券融资成本;区域内的传染效应与违约时间距离负相关,当时间距离增长时,传染效应变弱,甚至消失;债券违约风险对不同性质企业的传染效应不同,民营企业受影响尤为显著。  相似文献   
893.
This article specifies an efficient numerical scheme for computing optimal dynamic prices in a setting where the demand in a given period depends on the price in that period, cumulative sales up to the current period, and remaining market potential. The problem is studied in a deterministic and monopolistic context with a general form of the demand function. While traditional approaches produce closed-form equations that are difficult to solve due to the boundary conditions, we specify a computationally tractable numerical procedure by converting the problem to an initial-value problem based on a dynamic programming formulation. We find also that the optimal price dynamics preserves certain properties over the planning horizon: the unit revenue is linearly proportional to the demand elasticity of price; the unit revenue is constant over time when the demand elasticity is constant; and the sales rate is constant over time when the demand elasticity is linear in the price. 1We acknowledge professor robert e. kalaba for initiating this work and suggesting solution methods.  相似文献   
894.
陈超 《经济数学》2003,20(3):18-21
本文运用 Cox、Ross和 Rubinstein的方法 ,建立了股票价格离散时间的跳 -扩散模型 ,通过无套利理论推导出离散时间的欧式期权和美式期权定价公式  相似文献   
895.
We consider a hierarchical network game with multiple links, a single service provider, and a large number of users with multiple classes, where different classes of users enter the network and exit it at different nodes. Each user is charged by the service provider a fixed price per unit of bandwidth used on each link in its route, and chooses the level of its flow by maximizing an objective function that shows a tradeoff between the disutility of the payment to the service provider and congestion cost on the link the user uses, and the utility of its flow. The service provider, on the other hand, wishes to maximize the total revenue it collects. We formulate this problem as a leader-follower (Stackelberg) game, with a single leader (the service provider, who sets the price) and a large number of Nash followers (the users, who decide on their flow rates). We show that the game admits a unique equilibrium, and obtain the solution in analytic form. A detailed study of the limiting case where the number of followers is large reveals a number of interesting and intuitive properties of the equilibrium, and answers the question of whether and when the service provider has the incentive to add additional capacity to the network in response to an increase in the number of users on a particular link.  相似文献   
896.
We study the dynamic pricing decisions for competitive network service providers. We assume that each competing firm follows a three-part pricing scheme, which consists of an ongoing membership fee, a usage fee for communications within the networks, and another usage fee for communications across the networks. The difference between the two usage fees is the network-based price discount that allows price discrimination. We study the firms problems as a differential game and establish the optimal pricing policy as a Nash equilibrium feedback strategy depending on only the network sizes (i.e., the number of subscribers). We compare the dynamic network-based discount with the static discount. In the special case of a uniform calling pattern, we find that the firm network-based dynamic discount is always lower than the static discount; we find also that the firm that has a larger network can offer a bigger discount. These results are useful particularly for managers. To get further insights into the dynamic pricing policies, we explore the case of symmetric competition using numerical simulation.Communicated by G. Leitmann  相似文献   
897.
This paper extends the Black-Scholes methodology to payoffs that are functions of a stochastically varying variable that can be observed but not traded. The stochastic price process proposed in this paper satisfies a partial differential equation that is an extension of the Black-Scholes equation. The resulting price process is based on projection onto the marketed space, and it is universal in the sense that all risk-averse investors will find that, when priced according to the process, the asset cannot improve portfolio performance relative to other assets in the market. The development of the equation and its properties is facilitated by the introduction of an operational calculus for pricing. The results can be put in risk-neutral form. Perfect replication is not generally possible for these derivatives, but the approximation of minimum expected squared error is determined by another partial differential equation.  相似文献   
898.
We study how the threat of entry affects financial contracting between an incumbent firm and a bank, in a stochastic and dynamic environment. Contracts are short term and public. We determine the effects of the first period financial contract on the first period outputs in face of the threat of entry. Specifically, it is shown that the distance between first period outputs is increased due to potential entry. This is due to two underlying effects: first, the threat of entry reduces the signal dampening effect and thus the surplus left to the low cost incumbent is reduced. Second, learning is more valuable as it decreases the probability of entry. Indeed, experimentation takes on a strategic form, since the bank must take into account the impact of the possible game on its expected profits. This work integrates the agency problem between a firm and its financial intermediary with the issue of entry-deterrence under uncertainty.  相似文献   
899.
In this paper, we present a Quasi-Monte Carlo approach for pricingEuropean-style Asian options, i.e. for options whose pay-offdepends on the average price of the underlying asset where theaverage is extended over a fixed period up to the maturity date.Following a recent development in mathematical finance, we assumethat the log returns of the asset are not normally but hyperbolicallydistributed. This hypothesis is approved by several authorswith different statistic tests on real financial data. The aimof this paper is to advance the hyperbolic model to the pricingof Asian options, since there only exist pricing formulae forplain vanilla options and some types of exotic options (e.g.power call options, barrier options) so far. We show how onecan obtain prices of general Asian options in such incompletemarkets in an efficient way.  相似文献   
900.
In this work, we propose a macroscopic phenomenological model that is based on the classical framework of thermodynamics of irreversible processes and accounts for the effect of multiaxial stress states and non-proportional loading histories. The model is able to account for the evolution of both twinned and detwinned martensite. Moreover, reorientation of the product phase according to loading direction is specifically accounted for. Towards this purpose the inelastic strain is split into two contributions deriving, respectively, from creation of detwinned martensite and reorientation of previously existing martensite variants. Computational tests demonstrate the ability of the model to simulate the main aspects of the shape memory response in a one-dimensional setting and some of the features that have been experimentally found in the case of multiaxial non-proportional loading histories. Experimental non-proportional loading paths have also been simulated and a good qualitative agreement between numerical and experimental response is observed.  相似文献   
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