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31.
Sources and current methods of analysis of uncertainty from randomness, fuzziness and ignorance or incomplete knowledge in seismic hazard assessment problem are briefly discussed at beginning; understandings of the authors are then presented in the following order. All three types of uncertainty come from incomplete knowledge. Probabilistic method can be applied to all of them, objective probability for random factors and subjective probability for the other two types of uncertain factors. Discrete subjective probability mass functions for incomplete and fuzzy factors can be obtained from logic-tree and membership functions respectively. Fractile curves may be used to show the scattering of any uncertainty factor, but a unified probabilistic treatment may be applied to any combination of all three types of uncertainty. 相似文献
32.
蔡绯 《中国计量学院学报》1996,(1)
本文根据压力传感器(静态)国家计量检定规程,对压力传感器静态检定装置进行误差分析,得出该装置的测量不确定度。最后,通过实例说明实际测量不确定度与理论分析相符合。 相似文献
33.
Marcela Brugnach Andrew Tagg Florian Keil Wim J. de Lange 《Water Resources Management》2007,21(7):1075-1090
The use of computer models offers a general and flexible framework that can help to deal with some of the complexities and
difficulties associated with the development of water management plans as prescribed by the Water Framework Directive. However,
despite the advantages modelling presents, the integration of information derived from models into policy is far away from
being trivial or the norm. Part of the difficulties of this integration is rooted in the lack of confidence policy makers
have on the incorporation of modelling information into policy formulation. In this paper we examine the reasons for this
apparent lack of confidence and explore how some tools, presently in use, address this problem. We conclude that public confidence
in models is highly dependent on the way uncertainties are addressed and suggest possible directions of action to improve
the current situation. Four real case studies illustrate how computer models have been used in The Netherlands for carrying
out management plans at regional and national scale. We suggest that the solution to integrate modelling information into
policy formulation lies on both the modelling and the policy-making communities. 相似文献
34.
35.
Fusion of multi-sensor information is an important technology, which is growing exponentially due to its tremendous application potential in many areas. Effective fusion of data from sensors is very critical in increasing an intelligent system's capability to accomplish complex tasks. Appropriate fusion technologies are needed to be developed specially when a system requires redundant sensors to be used. More the redundancy in sensors, more is the computational complexity for controlling the system and more is its intelligence level. This research presents a strategy developed for multiple sensor fusion, based on geometric optimization. Each sensor's uncertainty has been modeled using classical Lagrangian optimization techniques. However, the uniqueness and effectiveness of the present technique lies on the fact that starting from the optimized value as initial estimate the accuracy of the sensory information has further been improved up to any pre defined bounded range, by developing two architectures – FFA (fission–fusion architecture) and FDD (fusion in differential domain). Sufficient evidences and analyses have been provided in the paper to show its effectiveness in various applications. 相似文献
36.
A stochastic model is proposed for a basic mechanism in the formation of uncertainties in physical quantity measurements.
__________
Translated from Izmeritel'naya Tekhnika, No. 1, pp. 12–17, January, 2006. 相似文献
37.
The vast majority of the project scheduling research efforts over the past several years have concentrated on the development
of workable predictive baseline schedules, assuming complete information and a static and deterministic environment. During
execution, however, a project may be subject to numerous schedule disruptions. Proactive-reactive project scheduling procedures
try to cope with these disruptions through the combination of a proactive scheduling procedure for generating predictive baseline
schedules that are hopefully robust in that they incorporate safety time to absorb anticipated disruptions with a reactive
procedure that is invoked when a schedule breakage occurs during project execution.
In this paper we discuss the results obtained by a large experimental design set up to evaluate several predictive-reactive
resource-constrained project scheduling procedures under the composite objective of maximizing both the schedule stability
and the timely project completion probability. 相似文献
38.
Sets of color tiles are available from the National Institute of Standards and Technology calibrated using the NIST 0:45 Reflectometer. The uncertainties associated with the measured values for the color tiles are an indispensable component of the calibration report that accompanies these tiles. A systematic, analytical approach developed previously was applied to the particular case of the reference instrument and color tile set, taking into account the operation and characteristics of the instrument and the spectral properties of the set. The primary sources of uncertainty were identified, and the resulting uncertainties in the color space values L*, a*, and b* were determined. In general, the uncertainties are lowest for those color tiles whose reflectance factors are nearly constant with wavelength. Published in 2008 by John Wiley & Sons, Inc. Col Res Appl, 33, 100–107, 2008 相似文献
39.
通过火焰原子吸收光谱法对水中的锑量进行了测定,对影响测量结果的不确定度分量进行了量化的计算,从而得出影响锑量测量不确定的主要因素是测量样品消解液中的锑的质量浓度引起的不确定度. 相似文献
40.