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991.
Torquati M. Mencagli G. Drocco M. Aldinucci M. De Matteis T. Danelutto M. 《The Journal of supercomputing》2019,75(8):4114-4131
This work studies the issues related to dynamic memory management in Data Stream Processing, an emerging paradigm enabling the real-time processing of live data streams. In this paper, we consider two streaming parallel patterns and we discuss different implementation variants related to how dynamic memory is managed. The results show that the standard mechanisms provided by modern C++ are not entirely adequate for maximizing the performance. Instead, the combined use of an efficient general purpose memory allocator, a custom allocator optimized for the pattern considered and a custom variant of the C++ shared pointer mechanism, provides a performance improvement up to 16% on the best case.
相似文献992.
993.
融合无监督和监督学习策略生成的多分类决策树 总被引:6,自引:0,他引:6
提出了一种融合无监督和监督两种学习策略生成多分类决策树的方法.它首先利用无监督聚类方法能够发现待分类样本之问的内在联系和规律的特点,确定出最为符合多类样本分布特征的决策树的树型,继而利用监督学习支持向量机的方法对样本进行准确的分类,通过采用核函数和不对称的Lagrangian系数限制条件,支持向量机很好的解决了样本特征空间上的线性不可分性和决策树型确定过程中出现的训练样本不对称性的影响、该方法具有较高的计算效率和准确性,在实验申取得了比较好的结果. 相似文献
994.
Giovanni Sparacino Gianluigi Pillonetto Massimo Capello Giuseppe De Nicolao Claudio Cobelli 《Computer methods and programs in biomedicine》2002,67(1):67-77
Deconvolution allows the reconstruction of non-accessible inputs (e.g. hormone secretion rate) from their causally-related measurable effects (e.g. hormone plasma concentration). Deconvolution is challenging under several aspects both general (e.g. determination of a suitable trade-off between data fit and solution smoothness in order to contrast ill-conditioning, assessment of the confidence intervals) as well as specific of physiological systems (e.g. non-uniform and infrequent data sampling). Recently, a stochastic regularization approach has been proposed and validated to handle these difficulties (De Nicolao et al., Automatica 33 (1997) 851-870). In this paper, an interactive program, WINSTODEC, is presented to allow the clinical investigator to easily obtain the solution of a deconvolution problem by this approach. 相似文献
995.
This paper deals with the regulation of the biomass specific growth rate, which is an important goal in many fed-batch fermentation processes. The proposed control system is based on the minimal model paradigm, requiring only biomass and volume measurement along with some bounds on the reaction rate. The controller has the structure of a partial state feed-back with adjustable gain. An integral-proportional control algorithm is designed to adjust this gain. It is inspired in concepts of invariant control and system immersion. First, a nonlinear integral action that makes invariant a goal manifold defined by a reference model dynamics is developed. Then, a proportional output error feed-back is incorporated to the control law with the aim of fastening convergence. Stability is investigated in detail using Lyapunov functions. To implement the control law, an estimation of the growth rate is required like any other PI-like controller. Because of its strong convergence properties, a sliding observer that requires the same process information as the controller is used for this task, although conventional continuous observers can alternatively be used provided they are fast enough to preserve stability. Simulation results showing the transient response and robustness features of the controller under nominal and perturbed scenarios are presented. 相似文献
996.
An evaluation was made of the use of bibliometric indicators for five disciplines in the humanities (social history, general linguistics, general literature, Dutch literature, and Dutch language) and three disciplines in the social and behavioural sciences (experimental psychology, anthropology, and public administration) in the Netherlands. Articles in journals were the predominant outlet in all disciplines. Monographs and popularizing articles were more important outlets in softer fields than in harder ones. The enlightenment function of scholarship was especially evident in Dutch literature and language, and public administration. Only some of the humanities disciplines are locally oriented. Although many publications were written in English, only experimental psychology, general linguistics, anthropology, and genrral literature were internationally oriented regarding output media. The impact of departments differed greatly both within and between disciplines. For all disciplines, bibliometric indicators are potentially useful for monitoring international impact, as expert interviews confirmed. Especially in Dutch language, Dutch literature and public administration, ISI-citation data are not very useful for monitoring national impact. 相似文献
997.
A rapidly solidified (Co, Fe)3O4 spinel was formed in a cobalt-iron-phosphate glass matrix by gas atomization of melts of composition 37.5% mol % CoO, 37.5%Fe2O3, 25% P2O5; and 40% CoO, 40% Fe2O3, 20% P2O5, and the material has been characterized using size analysis, X-ray diffraction, Mössbauer spectroscopy, and scanning electron microscopy with energy dispersive X-ray spectroscopy.In the 20 mol % P2O5 composition, atomized powder 50–100m in diameter contained 33 wt % (Co, Fe)3O4. The ferrite crystallized as randomly oriented, faceted dendrites parallel to 100, and the growth was apparently diffusion controlled. Unlike the ferrite, where iron is in both tetrahedral and octahedral coordination, the iron in the glassy matrix was predominantly in distorted octahedral coordination. Overall particle size distributions were broad (15–700m), with 50 wt % smaller than 200m. The maximum in the size distribution shifted from 150 to 80m on increasing the atomizing pressure from 7 to 20 bar (100 to 300 psi). Calculations have shown that the cooling rates obtained with oxide melts vary strongly with droplet size, and less strongly with melt temperature. 相似文献
998.
In this paper we consider some extensions of the Linear Complementarity Problem, which is one of the fundamental problems in mathematical programming. More specifically we consider the Linear Dynamic Complementarity Problem (LDCP), the Generalized Linear Complementarity Problem (GLCP) and the Extended Linear Complementarity Problem (ELCP). In this note we show that the LDCP is a special case of the ELCP and the GLCP. 相似文献
999.
Viviane Torres Da Silva Carlos J. P. De Lucena 《Autonomous Agents and Multi-Agent Systems》2004,9(1-2):145-189
In this paper we propose a multi-agent system modeling language (MAS-ML) that extends UML (Unified Modeling Language) based on structural and dynamic properties presented in a conceptual framework (metamodel) called Taming Agents and Objects (TAO). Our focus is the adaptation according to TAO concepts of the static Class diagram and the interaction Sequence diagram proposed by UML. These two diagrams have been chosen because they are the most commonly used and because it is possible to use them to illustrate both the structural and dynamic aspects of TAO metamodel. We propose a conservative extension of the UML metamodel, which includes agent-related notions that are part of the TAO conceptual framework while preserving all object-related concepts, which constitute the UML metamodel. The main difference between our approach and the others presented in the literature is the clear definition and representation of the elements that compose MASs and their corresponding behavior. In order to extend UML with TAO non-object concepts, it is not possible to use only the three basic extensions mechanisms provided by UML and new metaclasses and stereotypes have been created and associated with the UML metamodel. 相似文献
1000.
Patterned electroplating of micrometer scale magnetic structures on glass substrates 总被引:1,自引:0,他引:1
de Vries A.H.B. Kanger J.S. Krenn B.E. van Driel R. 《Journal of microelectromechanical systems》2004,13(3):391-395
This paper has developed a new method of micro patterned electroplating that enables the fabrication of micrometer scale magnetic structures on glass substrates. In contrast to other methods, the process as developed here leaves the surrounding substrate area untouched: that is there is no seed layer present except underneath the magnetic structures. Patterned cobalt layers of thicknesses up to 8 /spl mu/m were fabricated exhibiting high saturation (1.5 T) and low coercive force. These layers have been used to create micrometer scale magnetic poles (magnetic tweezers) for biological and biophysical applications, where a clean untouched glass substrate in the sample area is most important. The technique, however, can be used in any situation where a residual seed layer on the surrounding area is unwanted, and afterwards removal of this seed layer is difficult or impossible. 相似文献