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31.
32.
Narad Rampersad Nicolae Santean Jeffrey Shallit Bala Ravikumar 《Theoretical computer science》2009,410(24-25):2431-2441
For each basic language operation we define its “unique” counterpart as being the operation that results in a language whose words can be obtained uniquely through the given operation. These unique operations can arguably be viewed as combined basic operations, placing this work in the popular area of state complexity of combined operations on regular languages. We study the state complexity of unique rational operations and we provide upper bounds and empirical results meant to cast light into this matter. Equally important, we hope to have provided a generic methodology for estimating their state complexity. 相似文献
33.
34.
A genetic algorithm-based artificial neural network model for the optimization of machining processes 总被引:5,自引:2,他引:3
Artificial intelligent tools like genetic algorithm, artificial neural network (ANN) and fuzzy logic are found to be extremely
useful in modeling reliable processes in the field of computer integrated manufacturing (for example, selecting optimal parameters
during process planning, design and implementing the adaptive control systems). When knowledge about the relationship among
the various parameters of manufacturing are found to be lacking, ANNs are used as process models, because they can handle
strong nonlinearities, a large number of parameters and missing information. When the dependencies between parameters become
noninvertible, the input and output configurations used in ANN strongly influence the accuracy. However, running of a neural
network is found to be time consuming. If genetic algorithm-based ANNs are used to construct models, it can provide more accurate
results in less time. This article proposes a genetic algorithm-based ANN model for the turning process in manufacturing Industry.
This model is found to be a time-saving model that satisfies all the accuracy requirements. 相似文献
35.
Sreedhar Ganapuram G.T. Vijaya Kumar I.V. Murali Krishna Ercan Kahya M. Cüneyd Demirel 《Advances in Engineering Software》2009,40(7):506-518
The objective of this study is to explore the groundwater availability for agriculture in the Musi basin. Remote sensing data and geographic information system were used to locate potential zones for groundwater in the Musi basin. Various maps (i.e., base, hydrogeomorphological, geological, structural, drainage, slope, land use/land cover and groundwater prospect zones) were prepared using the remote sensing data along with the existing maps. The groundwater availability of the basin is qualitatively classified into different classes (i.e., very good, good, moderate, poor and nil) based on its hydrogeomorphological conditions. The land use/land cover map was prepared for the Kharif season using a digital classification technique with the limited ground truth for mapping irrigated areas in the Musi basin. The alluvial plain in filled valley, flood plain and deeply buried pediplain were successfully delineated and shown as the prospective zones of groundwater. 相似文献
36.
Information Systems and e-Business Management - Collaborative filtering (CF) is a popular and widely accepted recommendation technique. CF is an automated form of word-of-mouth communication... 相似文献
37.
Alagar S. Venkatesan S. 《IEEE transactions on pattern analysis and machine intelligence》2001,27(8):704-714
Global predicate detection, which is an important problem in testing and debugging distributed programs, is very hard due to the combinatorial explosion of the global state space. The paper presents several techniques to tackle the state explosion problem in detecting whether an arbitrary predicate Φ is true at some consistent global state of a distributed system. We present space efficient online algorithms for detecting Φ. We then improve the performance of our algorithms, both in space and time, by increasing the granularity of the execution step from an event to a sequence of events in each process 相似文献
38.
Exploratory tools that are sensitive to arbitrary statistical variations in spike train observations open up the possibility of novel neuroscientific discoveries. Developing such tools, however, is difficult due to the lack of Euclidean structure of the spike train space, and an experimenter usually prefers simpler tools that capture only limited statistical features of the spike train, such as mean spike count or mean firing rate. We explore strictly positive-definite kernels on the space of spike trains to offer both a structural representation of this space and a platform for developing statistical measures that explore features beyond count or rate. We apply these kernels to construct measures of divergence between two point processes and use them for hypothesis testing, that is, to observe if two sets of spike trains originate from the same underlying probability law. Although there exist positive-definite spike train kernels in the literature, we establish that these kernels are not strictly definite and thus do not induce measures of divergence. We discuss the properties of both of these existing nonstrict kernels and the novel strict kernels in terms of their computational complexity, choice of free parameters, and performance on both synthetic and real data through kernel principal component analysis and hypothesis testing. 相似文献
39.
局部线性嵌入算法(LLE)是流形学习中非线性数据降维的重要方法之一。考虑数据点分布大多呈现不均匀性,LLE对近邻点的选取方式将会导致大量的信息丢失。根据其不足,提出一种基于数据点松紧度的局部线性嵌入改进算法——tLLE算法,针对数据点分布不均匀的数据集,tLLE算法能有效地进行维数约简,且具有比LLE更好的降维效果。在人造数据和现实数据上的嵌入以及分类识别结果表明了tLLE算法的有效性。 相似文献
40.
L. J. Dhareshwar S. Chaurasia C. G. Murali N. K. Gupta B. K. Godwal 《Journal of Materials Science》2006,41(5):1623-1630
X-ray and ion emissions from high temperature plasmas from solid targets with different atomic numbers have been studied.
Plasma is generated using a high power Nd:Glass laser generating focused intensity in the range of 1012 to 1013 Watts/cm2 on targets. Plasma temperature is typically between 50 to 100 eV. X-ray emission scaling as a function of laser intensity
as well as ion velocity has been measured in these targets. Non-uniform plasma expansion and generation of fast ions are observed
for targets with higher atomic numbers. 相似文献