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排序方式: 共有3210条查询结果,搜索用时 31 毫秒
1.
We study a location-allocation-routing problem for distribution of the injured in a disaster response scenario, considering a three-type transportation network with separate links. A circle-based approach to estimate the impacts of the disaster is presented. After formulating relations for computing the percentage of the injured, the destruction percentage and the damage-dependent travel times, the problem is formulated as an integer nonlinear program. We utilize a genetic algorithm and a discrete version of the imperialist competitive algorithm for solving large problems. An empirical study focused on earthquakes in Tabriz, Iran, illustrates applicability of the proposed model and performance of the proposed algorithms.  相似文献   
2.
Advance selling is a marketing strategy commonly used by online retailers to increase sales by exploiting consumer valuation uncertainty. Recently, some online retailers have started to allow refunds on products sold in advance. On the one hand this reduces the net advance sales, but on the other hand it allows a higher advance sales price. This research is the first to explore the overall effect of allowing a refund on profits from advance sales, identifying conditions where advance selling with or without refunds (or no advance selling at all) is best. We analytically compare the profits of three advance selling strategies: none, without refund, and with refund. We show that selling in advance and allowing a refund is optimal for products with a relatively small profit margin and small strategic market size, and that the added profit can be considerable. Our results guide managers in selecting the right advance selling strategy. To facilitate this, we graphically display, based on the two dimensions of regular profit margin and strategic market size, under what conditions the different strategies are optimal.  相似文献   
3.
We study individually rational rules to be used to allot, among a group of agents, a perfectly divisible good that is freely available only in whole units. A rule is individually rational if, at each preference profile, each agent finds that her allotment is at least as good as any whole unit of the good. We study and characterize two individually rational and efficient families of rules, whenever agents' preferences are symmetric single-peaked on the set of possible allotments. Rules in the two families are in addition envy-free, but they differ on whether envy-freeness is considered on losses or on awards. Our main result states that (a) the family of constrained equal losses rules coincides with the class of all individually rational and efficient rules that satisfy justified envy-freeness on losses and (b) the family of constrained equal awards rules coincides with the class of all individually rational and efficient rules that satisfy envy-freeness on awards.  相似文献   
4.
We study the optimal execution problem with multiplicative price impact in algorithmic trading, when an agent holds an initial position of shares of a financial asset. The interselling decision times are modeled by the arrival times of a Poisson process. The criterion to be optimized consists in maximizing the expected net present value of the gains of the agent, and it is proved that an optimal strategy has a barrier form, depending only on the number of shares left and the level of the asset price.  相似文献   
5.
This study investigates the operating performance of firms listed on the Taiwan stock exchange following the initial resignation of independent directors. The results show that the firms’ operating performance following the resignation of these directors has not only deteriorated, but is also significantly below the industry average. In addition, firms with a relatively severe agency problem, including firms that have lower insider or institutional shareholdings, receive audit opinions other than unqualified opinions or change their auditors prior to the resignation of the independent directors, tend to perform more poorly following the resignation.  相似文献   
6.
Some agents are more accurate than others in estimating the best policy. The more accurately an agent estimates a policy's effects, the more he will resist biases, such as bribes from a special interest. Thus, a special interest needs to pay a larger bribe to an accurate agent than to an inaccurate agent. The accurate agent who is biased will then more likely cause harm than does an inaccurate agent who favors the special interest. Therefore, the principal may gain more from controlling biases of an accurate agent than of an inaccurate one. Thus, high ability of public officials may be associated with little corruption.  相似文献   
7.
提出一种针对复杂机电液系统的虚拟仿真试验方法,分别在ADAMS、AMESim、MATLAB/Simulink软件中建立机械子系统、液压子系统和控制子系统模型,并基于软件间接口技术,建立动态数据共享通道,实现系统的全面仿真分析,为系统设计与优化、控制策略选择等提供依据.该方法对于复杂机电液系统仿真分析具有普遍适用性,对缩短产品开发周期、降低产品研发成本、减轻仿真工作复杂性具有重要意义.  相似文献   
8.
This paper aimed to present an original approach for solving the aircraft stand allocation (SA) problem dynamically when due to operational disturbances, the planned allocation cannot be accomplished. The proposed Multiple-criteria Dynamic Stand Allocation (MDSA) method uses fuzzy logic to support decision-making under uncertainty. The MDSA method provides effective solutions in a short time, necessary for traffic management in case of delays, emergency, and untypical cases. It considers partially conflicting points of view of different airport users (airport managers, air traffic controllers, airlines, handling agents, and passengers) and may significantly support managers on the SA problem. The approach proposed can also be used for creating an initial SA plan for a considerable number of aircraft.  相似文献   
9.
研究跨行政区域界面管理问题,对于实现协同目标、提升协同绩效具有重要意义。本文主要研究跨行政区域协同创新界面类型、成因,应对界面障碍策略等问题。结果表明,从协同创新演化及其协同机理来看,跨行政区域主体协同创新界面可以分为内外界面两类;跨行政区域协同创新形成的界面主要有制度、知识、技术、交易、组织和管理等表现形式,起因为界面对应的壁垒。最后提出通过构建协同创新平台来解决跨行政区域协同创新界面障碍的设想,设计了平台形式、结构及其运行机制。  相似文献   
10.
We consider a robust consumption‐investment problem under constant relative risk aversion and constant absolute risk aversion utilities. The time‐varying confidence sets are specified by Θ, a correspondence from [0, T] to the space of the Lévy triplets, and describe a priori drift, volatility, and jump information. For each possible measure, the log‐price processes of stocks are semimartingales, and the triplet of their differential characteristics is almost surely a measurable selector from the correspondence Θ. By proposing and investigating the global kernel, an optimal policy and a worst‐case measure are generated from a saddle point of the global kernel, and they constitute a saddle point of the objective function.  相似文献   
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