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171.
幂型支付的欧式期权定价公式   总被引:16,自引:6,他引:10  
在等价鞅测度框架下,讨论了(在到期时刻)期权处于实值状态时支付函数为幂型的股票欧式期权定价公式.这里我们假设无风险利率,股票预期收益率和股价波动率都是时间的确定性函数.本文结果不但包含了原始的Black-Scholes公式,而且可用于上封顶与下保底(幂型)欧式看涨期权的定价.  相似文献   
172.
铀资源是军民两用的重要战略资源,有必要研究其价格变化为政府决策提供依据.采用基于Schwarz信息准则的统计变点检测方法,识别出1990-2013年国际天然铀价格的多个均值-方差变点,据此将国际天然铀价格的变化分为稳中下降期、大幅上扬期、震荡回归期和持续下降期四个阶段.研究结果表明,核事故、二次铀源、核电政策是影响国际天然铀价格的重要因素,同时天然铀逐渐显示出其商品的属性,其价格受供需关系的影响明显.  相似文献   
173.
We begin this paper by identifying a class of stochastic mixed-integer programs that have column-oriented formulations suitable for solution by a branch-and-price algorithm (B&P). We then survey a number of examples, and use a stochastic facility-location problem (SFLP) for a detailed demonstration of the relevant modeling and solution techniques. Computational results with a scenario representation of uncertain costs, demands and capacities show that B&P can be orders of magnitude faster than solving the standard formulation by branch and bound. We also demonstrate how B&P can solve SFLP exactly – as exactly as a deterministic mixed-integer program – when demands and other parameters can be represented as certain types of independent, random variables, e.g., independent, normal random variables with integer means and variances. Kevin Wood thanks the Office of Naval Research, Air Force Office of Scientific Research, the Naval Postgraduate School (NPS) and the University of Auckland for their support. Eduardo Silva thanks NPS and the Brazilian Navy for their support. Both authors are grateful to the COIN-OR team for assistance with computational issues, as well as to two anonymous referees for highly useful, constructive criticism.  相似文献   
174.
考虑突发事件导致市场需求大幅波动、市场价格随机波动,构建生产成本信息不对称时应急供应链的数量弹性契约模型,寻找最优定价及订货策略;与完全信息情形对比,分析突发事件的信息共享及其对供应链最优决策的影响程度。研究发现,在生产成本信息不对称情形下,突发事件发生时,虽然零售商设计的数量弹性契约可以有效体现真实生产成本,但对供应链协调不起作用。同时,如果市场需求规模缩减,制造商表现出隐藏信息行为,可以促使供应链整体效益增加。最后通过算例验证了这些结论。  相似文献   
175.
This paper presents the results of developing a branch and price algorithm and an ejection chain method for nurse rostering problems. The approach is general enough to be able to apply it to a wide range of benchmark nurse rostering instances. The majority of the instances are real world applications. They have been collected from a variety of sources including industrial collaborators, other researchers and various publications. The results of entering these algorithms in the 2010 International Nurse Rostering Competition are also presented and discussed. In addition, incorporated within both algorithms is a dynamic programming method which we present. The algorithm contains a number of heuristics and other features which make it very effective on the broad rostering model introduced.  相似文献   
176.
The structural theory of microdamage of homogeneous and composite materials is generalized. The theory is based on the equations and methods of the mechanics of microinhomogeneous bodies with stochastic structure. A single microdamage is modeled by a quasispherical pore empty or filled with particles of a damaged material. The accumulation of microdamages under increasing loading is modeled as increasing porosity. The damage within a single microvolume is governed by the Huber-Mises or Schleicher-Nadai failure criterion. The ultimate strength is assumed to be a random function of coordinates with power-law or Weibull one-point distribution. The stress-strain state and effective elastic properties of a composite with microdamaged components are determined using the stochastic equations of elasticity. The equations of deformation and microdamage and the porosity balance equation constitute a closed-form system of equations. The solution is found iteratively using conditional moments. The effect of temperature on the coupled processes of deformation and microdamage is taken into account. Algorithms for plotting the dependences of microdamage and macrostresses on macrostrains for composites of different structure are developed. The effect of temperature and strength of damaged material on the stress-strain and microdamage curves is examined __________ Translated from Prikladnaya Mekhanika, Vol. 43, No. 6, pp. 3–42, June 2007.  相似文献   
177.
Stochastic inventory control theory has focused on the order and/or pricing policy when the length of the selling period is known. In contrast to this focus, we examine the optimal length of the selling period—which we refer to as market exit time—in the context of a novel inventory replenishment problem faced by a supplier of a new, trendy, and relatively expensive product with a short life cycle. An important characteristic of the problem is that the supplier applies a price skimming strategy over time and the demand is modeled as a nonhomogeneous Poisson process with an intensity that is dependent on time. The supplier's problems of finding the optimal order quantity and market exit time, with the objective of maximizing expected profit, is studied. Procedures are proposed for joint optimization of the objective function with respect to the order quantity and the market exit time. Then, the effects of the order quantity and market exit time on the supplier's profitability are explored on the basis of a quantitative investigation. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
178.
目前人民币国际化已被广泛关注,国际大宗商品贸易、特别是能源贸易中计价货币绑定成为货币走向世界的新道路,因此研究人民币国际化与能源价格的关系对于进一步推动人民币国际化有着重要意义.本文选用渣打银行人民币环球指数来度量人民币国际化进程,利用协整、格兰杰因果和脉冲响应三种方法对人民币国际化与国内外石油及煤炭价格的互动关系进行了研究.实证结果表明:人民币国际化与能源价格之间存在长期均衡关系,且短期内能源价格变动对于人民币国际化变动都有着正向的影响.并且,石油价格以及国内煤炭价格是人民币国际化的格兰杰原因,而人民币国际化指数仅仅是国际煤炭价格的格兰杰原因;最后,通过脉冲响应分析,发现能源价格变动对人民币国际化进程有积极推动作用.  相似文献   
179.
蒋敏  孟志青  周娜  沈瑞 《运筹与管理》2020,29(10):40-48
以智能产品为研究对象,建立了差价补偿策略下制造商与销售商的博弈模型,分别通过纳什均衡博弈和斯塔克尔伯格博弈协调优化对制造商和销售商的决策行为进行探讨,得到了Nash均衡下制造商与销售商之间交易策略,讨论了斯塔克尔伯格博弈下制造商的最优订购、最优补偿系数和销售商的订购量之间关系,提出了求解在给定补偿系数下斯塔克尔伯格博弈协调优化的近似最优批发价与最优订购量的算法。通过数值实验表明,制造商占优势地位时,差价补偿策略能实现整体供应链的协调优化,提高销售商的订购量以及制造商和销售商的利润,说明差价补偿策略可以有效地改善零供关系。  相似文献   
180.
In a number of industries (e.g., the airplane industry, aerospace industry, auto industry, or computer industry), certain suppliers essentially have a monopoly on the production technology for key components, and inevitably manufacturers in these industries have common suppliers. A key part of manufacturers’ work with suppliers concerns improving the quality of their respective products, which gives rise to a collaborative activity usually termed as “supply quality management”. When the manufacturers are competitors, they do not wish to see a common supplier dividing his involvement in quality improvement unequally between themselves and their rivals. However, as the suppliers collaborate with several manufacturers, it is highly questionable whether their efforts will be strictly equivalent for each manufacturer. In this paper, a non-cooperative dynamic game is formulated in which a single supplier collaborates with two manufacturers on design quality improvements for their respective products. The manufacturers compete for market demand both on price and design quality. The paper analyzes how each party should allocate resources for quality improvement over time. In order to take into account the potential coordinating power of the compensation scheme adopted in this type of decentralized setting, we compare the possible outcomes under a wholesale price contract and a revenue-sharing contract.  相似文献   
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