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71.
Asset price dynamics is studied by using a system of ordinary differential equations which is derived by utilizing a new excess demand function introduced by Caginalp [4] for a market involving more information on demand and supply for a stock rather than their values at a particular price. Derivation is based on the finiteness of assets (rather than assuming unbounded arbitrage) in addition to investment strategies that are based on not only price momentum (trend) but also valuation considerations. For this new model and the older models which were extracted using the classical excess demand function by Caginalp and Balenovich [2] and [3], time evolutions of asset price are compared through numerical simulations.  相似文献   
72.
Abstract Fishing leads to truncation of a population's age and size structure. However, large‐sized fish are usually more valuable per unit weight than small ones. Nevertheless, these size‐related factors have mostly been ignored in bioeconomic modeling. Here, we present a simple extension to the Gordon–Schaefer model that accounts for variations in mean individual catch weight, and derive the feedback rule for optimal harvest in this setting. As the Gordon–Schaefer model has no population structure, size effects have to be accounted for indirectly. Here we assume a simple negative relationship between fishing effort and mean individual weight, and a positive relationship between mean catch weight and price. The aim is to emulate alterations of size structure in fish populations due to fishing and the influence of size on price per weight unit and eventually, net revenues. This demonstrates, on a general level, how such size‐dependent effects change the patterns of optimal harvest paths and sustainable revenue in single fish stocks. The model shows clear shifts toward lower levels of optimal effort and yield compared to classical models without size effects. This suggests that ignoring body size could lead to misleading assumptions and policies, potentially causing rent dissipation and suboptimal utilization of renewable resources.  相似文献   
73.
假设股票随机支付红利,且红利的大小与支付红利时刻及股票价格有关,并假设股票价格过程服从跳—扩散模型(其中跳跃过程为Poisson过程)的条件下,建立了股票价格行为模型,应用保险精算法给出了欧式看涨和看跌期权的定价公式,推广了Merton关于期权定价的结果。  相似文献   
74.
从企业社会责任对消费者偏好的影响入手,运用博弈论的基本思想,对制销供应链中,制造商与分销商一次性博弈的定价和利润分配策略进行了研究,并在此基础上对不同情况下制销双方重复性博弈的均衡结果进行了讨论.结果表明:在两类制销供应链中,联盟定价都是制销双方一次性博弈的唯一纳什均衡结果,且在制销双方商定的利润分配因子的取值范围内双方联盟后所得的利润高于联盟之前;在两类制销供应链中,制造商与分销商坚持联盟定价对双方的长期利润都是最优的.  相似文献   
75.
In this paper, we present a transform-based algorithm for pricing discretely monitored arithmetic Asian options with remarkable accuracy in a general stochastic volatility framework, including affine models and time-changed Lévy processes. The accuracy is justified both theoretically and experimentally. In addition, to speed up the valuation process, we employ high-performance computing technologies. More specifically, we develop a parallel option pricing system that can be easily reproduced on parallel computers, also realized as a cluster of personal computers. Numerical results showing the accuracy, speed and efficiency of the procedure are reported in the paper.  相似文献   
76.
We present a novel numerical scheme for the valuation of options under a well‐known jump‐diffusion model. European option pricing for such a case satisfies a 1 + 2 partial integro‐differential equation (PIDE) including a double integral term, which is nonlocal. The proposed approach relies on nonuniform meshes with a focus on the discontinuous and degenerate areas of the model and applying quadratically convergent finite difference (FD) discretizations via the method of lines (MOL). A condition for observing the time stability of the fully discretized problem is given. Also, we report results of numerical experiments.  相似文献   
77.
杨慧  戈磊  李颜戎  孙菲 《运筹与管理》2019,28(12):137-143
本文探讨从事不透明销售的零售商对顾客退货政策的选择问题。分别针对零售商垄断和竞争两种市场情况,建立不透明零售商与其它供应链成员(制造商或普通零售商)之间的博弈模型,获得唯一均衡解;对均衡结果进行结构化分析,给出不透明销售方式下采用全额退款政策的判别条件;针对均衡结果,分析零售商垄断情况下产品不透明参数的最优设计,以及零售商竞争情况下的市场分化情况;鉴于净残值参数在退货政策选择中的决定性作用,本文进一步探讨了净残值为正时全额退款政策对各参与方利润及产品需求和价格的影响,分析了净残值在其中的作用机理。本研究能够为不透明零售商制定退货政策和价格以及其它供应链成员制定相关决策提供支持。  相似文献   
78.
张子健  许茂增 《运筹与管理》2019,28(11):106-111
建立一个由制造商和销售商组成的二级供应链模型,在销售商向消费者销售制造商基础产品的同时提供可选附加品的供应链多产品定价背景下研究了制造商及销售商的定价策略。以消费者对附加品价值增值存在的异质性将基础产品及其附加品的消费市场细分为基础产品单独消费市场及产品共同消费市场。基于市场细分比例以及附加品价值增值程度,讨论了不同条件下制造商及销售商的定价策略以及所形成的供应链定价均衡,分析了产品定价均衡与市场细分比例、附加品价值增值程度之间的关系。  相似文献   
79.
借鉴中小制造型企业(SMPEs)在线渠道预售模式,考虑市场中存在预付订金和不预付订金的顾客,并将其退货情况引入到生产商利润表达式中,构建确定性和随机性市场需求下的SMPEs产品销售利润最大化模型,推导生产商产品最优定价的解析解;对比两种销售模式的利润,得到了生产商选择不同销售策略的条件。进一步考虑预付定金的产品数量、预交定金比例、退货数量是关于价格折扣敏感的情况,采用拉格朗日乘子法对生产商产品定价及优化问题进行研究,分析求得生产商销售策略(产品定价和价格折扣)的近似最优解。最后,通过数值算例对研究结论进行了验证并给出经济学解释。  相似文献   
80.
Taking flood catastrophe risk in China as the research background, aiming at the characteristics of flood loss ``low frequency and high loss', Bayesian inference method is used to fit the loss distribution, and Bayesian inference is used to obtain the loss frequency distribution and loss quota distribution of flood in China. On this basis, Monte Carlo simulation method is used to calculate the probability distribution of annual flood loss in China under different trigger conditions, and then CAPM is used to study the pricing of flood catastrophe bonds in China. It is concluded that under different trigger conditions, as the trigger value increases gradually, the corresponding trigger is triggered. Comparing the three types of bonds, it can be found that the price of bonds decreases with the decrease of principal guarantee ratio and the increase of principal loss ratio, that is, the investment risk is directly proportional to the return, which provides reference for issuing flood catastrophe bonds in China.  相似文献   
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