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81.
82.
Recent anthropological studies have demonstrated that low latitude ‘encounter’ foragers exploit their environments in energetically very efficient manners and closely track the environment as it changes. The paper begins to investigate how they manage to do this by proposing a simple decision making and learning rule developed from an evolutionary ecological basis. Having described the mathematical model the paper refers to simulation studies exploring this model which suggest that some of the seemingly complex aspects of hunter gatherer behaviour may result from the use of simple decision making and learning processes.  相似文献   
83.
Influence diagrams for representing Bayesian decision problems are redefined in a formal way using conditional independence. This makes the graphs somewhat more helpful for exploring the consequences of a clients state beliefs. Some important results about the manipulation of influence diagrams are extended and reviewed as is an algorithm for computing an optimal policy. Two new results about the manipulation of influence diagrams are derived. A novel influence diagram representing a practical decision problem is used to illustrate the methodologies presented in this paper.  相似文献   
84.
A major difficulty in the study of large-scale complex systems involving human decision-making with non-linear collective effects is that of obtaining pertinent data at the desired level of detail. A controlled experiment involving real commuters in a hypothetical computer simulated traffic system is described as an alternative approach of conducting observational studies to support the modelling of such complex dynamic interactive decision systems. An overview of the principal characteristics of the traffic system's evolution obtained in this experiment is presented. Also illustrated are the features of a proposed behavioral framework where users are viewed as boundedly rational seekers of a satisfactory choice outcome.  相似文献   
85.
We consider the variational inequality that represents the first-order optimality condition for the class of variational problems with the property that the integrand in the objective functional does not depend on the derivative of the unknown function. This allows the development of an iterative method for solving the statistical decision problem of testing simple hypotheses.  相似文献   
86.
A fuzzy-stochastic OWA model for robust multi-criteria decision making   总被引:3,自引:0,他引:3  
All realistic Multi-Criteria Decision Making (MCDM) problems face various kinds of uncertainty. Since the evaluations of alternatives with respect to the criteria are uncertain they will be assumed to have stochastic nature. To obtain the uncertain optimism degree of the decision maker fuzzy linguistic quantifiers will be used. Then a new approach for fuzzy-stochastic modeling of MCDM problems will be introduced by merging the stochastic and fuzzy approaches into the OWA operator. The results of the new approach, entitled FSOWA, give the expected value and the variance of the combined goodness measure for each alternative. Robust decision depends on the combined goodness measures of alternatives and also on the variations of these measures under uncertainty. In order to combine these two characteristics a composite goodness measure will be defined. The theoretical results will be illustrated in a watershed management problem. By using this measure will give more sensitive decisions to the stakeholders whose optimism degrees are different than that of the decision maker. FSOWA can be used for robust decision making on the competitive alternatives under uncertainty.  相似文献   
87.
The main concern of this article is to present the R UBIS method for tackling the choice problem in the context of multiple criteria decision aiding. Its genuine purpose is to help a decision maker to determine a single best decision alternative. Methodologically we focus on pairwise comparisons of these alternatives which lead to the concept of bipolar-valued outranking digraph. The work is centred around a set of five pragmatic principles which are required in the context of a progressive decision aiding methodology. Their thorough study and implementation in the outranking digraph lead us to define a choice recommendation as an extension of the classical digraph kernel concept.   相似文献   
88.
航空公司航线决策的一种系统方法   总被引:5,自引:0,他引:5  
本通过对航空公司基于现有运力选择航线这一决策问题的诸多影响因素的综合分析,根据经验和灵敏度分析的结果,提炼出适于决策的关键因素作为这个多目标决策问题的目标属性,给出了确定各属性值和其权的相应技术和方法,并运用适宜本问题的决策分析方法,完成决策过程,这是作提出的一种较为系统的航线决策概念和方法,也是一种可程序化的方法,借助于计算机并建立相应的数据库,能快速,方便地完成这一决策分析,对如何选择最佳的航线网络,也可类此采用本方法。  相似文献   
89.
We establish the optimality of structured replacement policies for a periodically inspected system that fails silently whenever the cumulative number of shocks, or the magnitude of a single shock it has received, exceeds a corresponding threshold. Shocks arrive according to a Markov-modulated Poisson process which represents the (controllable or uncontrollable) environment.  相似文献   
90.
All studies in the admission control of a service station make decisions at arrival epochs. When arrivals are internal and are rejected from a queue, the rejected jobs have to be routed to other stations in the system. However the system will not know whether a job will be admitted to a queue or not until its arrival epoch to that queue. Thus, the system has to react dynamically and agilely to the decisions made at a specific queue and may try several queues before finding a queue that admits the job. This paper remedies these difficulties by changing the decision epochs of the admission control from arrival epochs to departure epochs with the actions of switching (keeping) the arrival stream on or off. Thus upstream stations will have information on the admission status of their downstream stations all the time. It is proved that the optimal policy for this revised admission control system is of control limit type for an M/G/1 queue. Comparisons of the optimal values and optimal policies for the admission controls made at arrival epochs and at departure epochs are included in the paper.  相似文献   
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