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61.
《Information & Management》2020,57(2):103168
Partial least squares path modeling (PLS-PM) is an estimator that has found widespread application for causal information systems (IS) research. Recently, the method has been subject to many improvements, such as consistent PLS (PLSc) for latent variable models, a bootstrap-based test for overall model fit, and the heterotrait-to-monotrait ratio of correlations for assessing discriminant validity. Scholars who would like to rigorously apply PLS-PM need updated guidelines for its use. This paper explains how to perform and report empirical analyses using PLS-PM including the latest enhancements, and illustrates its application with a fictive example on business value of social media. 相似文献
62.
The multi-purpose forensics is an important tool for forge image detection. In
this paper, we propose a universal feature set for the multi-purpose forensics which is
capable of simultaneously identifying several typical image manipulations, including
spatial low-pass Gaussian blurring, median filtering, re-sampling, and JPEG
compression. To eliminate the influences caused by diverse image contents on the
effectiveness and robustness of the feature, a residual group which contains several highpass filtered residuals is introduced. The partial correlation coefficient is exploited from
the residual group to purely measure neighborhood correlations in a linear way. Besides
that, we also combine autoregressive coefficient and transition probability to form the
proposed composite feature which is used to measure how manipulations change the
neighborhood relationships in both linear and non-linear way. After a series of dimension
reductions, the proposed feature set can accelerate the training and testing for the multipurpose forensics. The proposed feature set is then fed into a multi-classifier to train a
multi-purpose detector. Experimental results show that the proposed detector can identify several typical image manipulations, and is superior to the complicated deep CNN-based
methods in terms of detection accuracy and time efficiency for JPEG compressed image
with low resolution. 相似文献
63.
This paper addresses reliable and efficient calculation of the mode of a multivariate sample, which is a classical fusion function. In particular, we focus on the inputs given on the unit simplex, when aggregating elements of Atanassov intuitionistic fuzzy sets, interval-valued fuzzy sets and their extensions, as well as compositional data. We outline the use of a specially designed 2-additive fuzzy measures and the Choquet integral for the purposes of reducing computational complexity in higher dimensions. We present computational analysis and benchmark four different methods of density-based mode estimation. 相似文献
64.
《工程(英文)》2021,7(9):1313-1325
The rapid advance of autonomous vehicles (AVs) has motivated new perspectives and potential challenges for existing modes of transportation. Currently, driving assistance systems of Level 3 and below have been widely produced, and several applications of Level 4 systems to specific situations have also been gradually developed. By improving the automation level and vehicle intelligence, these systems can be further advanced towards fully autonomous driving. However, general development concepts for Level 5 AVs remain unclear, and the existing methods employed in the development processes of Levels 0–4 have been mainly based on task-driven function development related to specific scenarios. Therefore, it is difficult to identify the problems encountered by high-level AVs. The essential logical and physical mechanisms of vehicles have hindered further progression towards Level 5 systems. By exploring the physical mechanisms behind high-level autonomous driving systems and analyzing the essence of driving, we put forward a coordinated and balanced framework based on the brain–cerebellum–organ concept through reasoning and deduction. Based on a mixed mode relying on the crow inference and parrot imitation approach, we explore the research paradigm of autonomous learning and prior knowledge to realize the characteristics of self-learning, self-adaptation, and self-transcendence for AVs. From a systematic, unified, and balanced point of view and based on least action principles and unified safety field concepts, we aim to provide a novel research concept and develop an effective approach for the research and development of high-level AVs, specifically at Level 5. 相似文献
65.
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67.
含高承压水黄土层中注浆堵水的理论与实践 总被引:11,自引:1,他引:11
在高承压水黄土层中掘井筒,使用冷冻法似乎又成了工程定例,但其高昂的施工费用常令建设者望而却步。而运用廉价的普通注浆的方法进行堵水能保证井筒安然通过,国内外鲜有成功 例。 相似文献
68.
Data are very important to build the digital mine. Data come from many sources, have different types and temporal states. Relations between one class of data and the other one, or between data and unknown parameters are more nonlinear. The unknown parameters are non-random or random, among which the random parameters often dynamically vary with time. Therefore it is not accurate and reliable to process the data in building the digital mine with the classical least squares method or the method of the common nonlinear least squares. So a generalized nonlinear dynamic least squares method to process data in building the digital mine is put forward. In the meantime, the corresponding mathematical model is also given. The generalized nonlinear least squares problem is more complex than the common nonlinear least squares problem and its solution is more difficultly obtained because the dimensions of data and parameters in the former are bigger. So a new solution model and the method are put forward to solve the generalized nonlinear dynamic least squares problem. In fact, the problem can be converted to two sub-problems, each of which has a single variable. That is to say, a complex problem can be separated and then solved. So the dimension of unknown parameters can be reduced to its half, which simplifies the original high dimensional equations. The method lessens the calculating load and opens up a new way to process the data in building the digital mine, which have more sources, different types and more temporal states. 相似文献
69.
70.
断层分形分布之间的相关关系 总被引:10,自引:0,他引:10
根据断层几何和其物理机理与特征,分析了断层数目分布、位移分布和间距分布的分形维之间的相关性。建立了断层系统表面迹的分形模型,研究了断层分形分布的分形维数与断层系统表面迹线分维的相关关系。只要测定出任意两种分布的分维就能推算出其它分布的分维值。 相似文献