全文获取类型
收费全文 | 1282篇 |
免费 | 231篇 |
国内免费 | 28篇 |
专业分类
化学 | 22篇 |
力学 | 20篇 |
综合类 | 86篇 |
数学 | 1332篇 |
物理学 | 81篇 |
出版年
2023年 | 8篇 |
2022年 | 52篇 |
2021年 | 57篇 |
2020年 | 46篇 |
2019年 | 48篇 |
2018年 | 44篇 |
2017年 | 57篇 |
2016年 | 65篇 |
2015年 | 48篇 |
2014年 | 85篇 |
2013年 | 154篇 |
2012年 | 60篇 |
2011年 | 69篇 |
2010年 | 79篇 |
2009年 | 92篇 |
2008年 | 94篇 |
2007年 | 80篇 |
2006年 | 60篇 |
2005年 | 45篇 |
2004年 | 26篇 |
2003年 | 47篇 |
2002年 | 31篇 |
2001年 | 19篇 |
2000年 | 28篇 |
1999年 | 23篇 |
1998年 | 13篇 |
1997年 | 13篇 |
1996年 | 14篇 |
1995年 | 6篇 |
1994年 | 11篇 |
1993年 | 6篇 |
1992年 | 10篇 |
1991年 | 2篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 9篇 |
1986年 | 1篇 |
1985年 | 8篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1959年 | 2篇 |
排序方式: 共有1541条查询结果,搜索用时 203 毫秒
101.
采用偏微分方程方法研究了彩虹障碍期权的定价问题,推导出它满足的偏微分方程,通过求解这个偏微分方程得出了八种彩虹障碍期权的定价公式及四个看涨——看跌平价公式. 相似文献
102.
This paper considers the option pricing problem for contingent claims of the European type in a (B,S)-market in which the stock price and the asset in the riskless bank account both have hereditary structures. The Black-Scholes
equation for the classical option pricing problem is generalized to an infinite-dimensional equation to include the effects
of time delay in the evolution of the financial market as well as a very general payoff function. A computational algorithm
for the solution is also obtained via a double sequence of polynomials of a certain bounded linear functional on a Banach
space and the time variable. 相似文献
103.
离散时间不完全金融市场中未定权益的定价 总被引:1,自引:0,他引:1
对一类连续时间不完全市场(其中的股票价格由Brown运动驱动),ElKarouiandQuenez[1]讨论了一般的不可达未定权益的定价问题.本文利用FollmerandKabanov[2]建立的分解定理,证明[1]中关于买方与卖方价格过程的结果与方法适用于一般的离散时间不完全金融市场(定理1).特别,关于买方与卖方价格我们给出另一种合理的解释(定理3). 相似文献
104.
A sojourn time analysis is provided for a cyclic-service tandem queue with general decrementing service which operates as follows: starting once a service of queue 1 in the first stage, a single server continues serving messages in queue 1 until either queue 1 becomes empty, or the number of messages decreases to k less than that found upon the server's last arrival at queue 1, whichever occurs first, where 1 ≤ k ≤ ∞. After service completion in queue 1, the server switches over to queue 2 in the second stage and serves all messages in queue 2 until it becomes empty. It is assumed that an arrival stream is Poissonian, message service times at each stage are generally distributed and switch-over times are zero. This paper analyzes joint queue-length distributions and message sojourn time distributions. 相似文献
105.
资产价格具有跳跃特征时,衍生于该资产的期权就不能利用传统的Black-Schoels公式进行定价。本主要研究基于Poisson过程和固定跳跃Merton模型的期权定价与风险对冲问题,利用e-套利定价法,得到期权的风险对冲策略所满足的偏微分方程和近似期权定价。 相似文献
106.
We consider the joint pricing and inventory control problem for a single product over a finite horizon and with periodic review. The demand distribution in each period is determined by an exogenous Markov chain. Pricing and ordering decisions are made at the beginning of each period and all shortages are backlogged. The surplus costs as well as fixed and variable costs are state dependent. We show the existence of an optimal (s, S, p)-type feedback policy for the additive demand model. We extend the model to the case of emergency orders. We compute the optimal policy for a class of Markovian demand and illustrate the benefits of dynamic pricing over fixed pricing through numerical examples. The results indicate that it is more beneficial to implement dynamic pricing in a Markovian demand environment with a high fixed ordering cost or with high demand variability. 相似文献
107.
108.
We consider the control of an infinite capacity shuttle which transports passengers between two terminals. The passengers
arrive at each terminal according to a compound Poisson process and the travel time from one terminal to the other is a random
variable following an arbitrary distribution. The following control limit policy is considered: dispatch the shuttle at terminali, at the instant that the total number of passengers waiting at terminali reaches or exceeds a predetermined control limitm
i
. The objective of this paper is to obtain the mean waiting time of an arbitrary passenger at each terminal for given control
valuesm
1 andm
2. We also discuss a search procedure to obtain the optimal control values which minimize the total expected cost per unit
time under a linear cost structure. 相似文献
109.
Javier Villarroel 《Physica A》2007,382(1):321-329
We present a model to describe the stochastic evolution of stocks that show a strong resistance at some level and generalize to this situation the evolution based upon geometric Brownian motion. If volatility and drift are related in a certain way we show that our model can be integrated in an exact way. The related problem of how to prize general securities that pay dividends at a continuous rate and earn a terminal payoff at maturity T is solved via the martingale probability approach. 相似文献
110.
基于多线程技术的智能小区管理服务系统构建 总被引:2,自引:0,他引:2
设计并实现了一个由485网络构成的智能小区数据采集、控制及管理服务系统,该系统能实现抄表、安防和物业管理等功能,对该系统的整体结构做了介绍,并讨论了中心主机管理服务系统软件的两大模块——通信引擎和管理平台,其中详细分析了多线程技术在通信引擎中的重要作用. 相似文献