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991.
企业技术创新能力指标体系的模糊理论综合评价   总被引:9,自引:0,他引:9  
根据我国具有一定规模的企业创新状况 ,构建了企业技术创新能力的指标体系 .运用模糊数学方法 ,对企业技术创新能力进行综合评价 ,为客观评价、及时调整企业技术创新战略提供了客观依据 ,有利于提高企业的技术创新能力  相似文献   
992.
Based on hypothesis of “base value” of water quality parameter, a universal index suitable to multi‐parameter water quality evaluation was presented, as the monitoring values of parameters in the water quality index formula in logarithm function form were replaced by their relative values, and optimizing the parameters of different indices in the formula was carried out by Genetic Algorithms. Each index of water quality can be weighted into comprehensive index by compromise active function. The correctitude of formula was verified by using this method to asses the water quality states of many spots. The formula has shown its simplicity of calculation, practicability, generality, comparability and objectivity. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 20: 368–373, 2004  相似文献   
993.
企业能力指数测评模型研究   总被引:9,自引:0,他引:9  
在新经济和全球化的影响下,企业之间的竞争演变为企业能力的竞争。企业要想生存发展,必须构建和提高自身的能力。因此,对企业能力做出科学的评估,从而确定企业战略、选择合作伙伴、优化供应链是十分重要的。本从企业能力及其指数定义出发,研究了企业能力的构成体系,利用模糊层次分析法,建立了企业能力指数测评模型,并给出了一个实例。  相似文献   
994.
基于非结构化模糊决策方法的设备采购方案评价   总被引:4,自引:0,他引:4  
为解决设备采购方案评价中存在的多目标决策问题以及弥补运用层次分析法(AHP法)和多因素价值理论(效用理论)解决此类问题的某些局限性,提出了运用非结构化模糊决策方法(NSFDM)进行设备采购方案评价。在论述了NSFDM的原理和步骤之后,以某项目空调系统采购为例,着重分析了NSFDM在设备采购方案评价中的应用。结果表明:相对于AHP法,NSFDM在建立层次结构模型时同一层次比较因素的数目可以超过9个,且判断矩阵易于通过一致性检验,因而NSFDM是解决设备采购方案评价和其它类似的复杂多目标决策问题的一种有效方法。  相似文献   
995.
Since an enormous number of different pollutants is usually simultaneously present in a certain environmental area, it must be expected that interactions between these pollutants may occur frequently. Nevertheless, not very much is known about the combined impact of several pollutants and the environmental policy ignores these effects in defining pollution standards and limits just for single pollutants. Moreover, it is not at all clear how these effects should precisely be described. Starting from definitions of interactions between different environmental influences introduced by Ott [7] and one of the present authors [8], new concepts of synergism (and antagonism and superposition) in a deterministic context will be presented. It is analyzed which properties an environmental quality index has to have in order to describe such interactions.  相似文献   
996.
The problem of the evaluation in floating-point arithmetic of a polynomial with floating-point coefficients at a point which is a finite sum of floating-point numbers is studied. The solution is obtained as an infinite convergent series of floating-point numbers. The algorithm requires a precise scalar product, but this can always be implemented by software in a high-level language without assembly language routines as we indicate. A convergence result is proved under a very weak restriction on the size of the degree of the polynomial in terms of the unit roundoff u; roughly speaking, the degree should not be larger than the square root of (1 + u)(2u). Even in the particular case when the point at which to evaluate the polynomial reduces to one floating-point number, we find a new simplified algorithm among the whole family that the preceding convergence result allows.

This problem occurs, among others, in the convergence of the Newton method to some real root of the given polynomial p. If we simply use the Horner scheme to evaluate the polynomial p in a neighbourhood of the root, in some cases the evaluation will contain no correct digits and will prevent us from getting convergence even to machine accuracy. The convergence of iterative methods, among which the Newton method, with added perturbations was the central theme of my talk given at the ICCAM'92. The second part will appear in a forthcoming paper. These added perturbations can represent for example forward or backward errors occurring in finite-precision computations.

The problem discussed here appears in validating some hypotheses of these general convergence results (see the forthcoming paper).  相似文献   

997.
期权理论在风险投资项目评估中的应用   总被引:16,自引:0,他引:16  
本在对传统的现金流折现法DCF法分析基础上,引进Block-Scholes期权定价模型,对传统的DCF方法进行改进,克服了DCF方法局限性,增加了风险投资项目决策的科学性。  相似文献   
998.
We study the modelling of the subjective sensation of discomfort for subjects seated during a long time, in terms of local discomforts. The methodology uses fuzzy measures and integrals in a multicriteria decision making process, which enables the modelling of complex interaction between variables. Results of the experiment are detailed, giving models with respect to different kinds of discomfort, and to different macro-zones of the body.  相似文献   
999.
The impact of bursty traffic on queues is investigated in this paper. We consider a discrete-time single server queue with an infinite storage room, that releases customers at the constant rate of c customers/slot. The queue is fed by an M/G/∞ process. The M/G/∞ process can be seen as a process resulting from the superposition of infinitely many ‘sessions’: sessions become active according to a Poisson process; a station stays active for a random time, with probability distribution G, after which it becomes inactive. The number of customers entering the queue in the time-interval [t, t + 1) is then defined as the number of active sessions at time t (t = 0,1, ...) or, equivalently, as the number of busy servers at time t in an M/G/∞ queue, thereby explaining the terminology. The M/G/∞ process enjoys several attractive features: First, it can display various forms of dependencies, the extent of which being governed by the service time distribution G. The heavier the tail of G, the more bursty the M/G/∞ process. Second, this process arises naturally in teletraffic as the limiting case for the aggregation of on/off sources [27]. Third, it has been shown to be a good model for various types of network traffic, including telnet/ftp connections [37] and variable-bit-rate (VBR) video traffic [24]. Last but not least, it is amenable to queueing analysis due to its very strong structural properties. In this paper, we compute an asymptotic lower bound for the tail distribution of the queue length. This bound suggests that the queueing delays will dramatically increase as the burstiness of the M/G/∞ input process increases. More specifically, if the tail of G is heavy, implying a bursty input process, then the tail of the queue length will also be heavy. This result is in sharp contrast with the exponential decay rate of the tail distribution of the queue length in presence of ‘non-bursty’ traffic (e.g. Poisson-like traffic). This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
1000.
作战方案评估智能决策支持系统研究   总被引:5,自引:0,他引:5  
作战决策是作战指挥的核心,作战指挥智能决策支持系统(IDSS)是用于辅助指挥员进行作战决策的计算机软件。它是指挥自动化的重要组成部分。本通过研究作战方案评估IDSS,探讨了作战指挥IDSS的结构及功能。  相似文献   
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