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排序方式: 共有1512条查询结果,搜索用时 15 毫秒
71.
Josefina Barrera-CortÉs Cinvestav Jean Pierre Astruc Roland Tufeu Ana MarÍa MartÍnez-Enriquez 《Applied Artificial Intelligence》2013,27(5):453-470
In this paper an analytical procedure implemented to structure the knowledge required by an expert system applied for controlling a chemical process is described. The analytical approach is based on L ifecycle of Systems and on Task Model approaches. It was validated with an experimental procedure related to the determination of the critical point of pure fluids (CO2, N2O, SF6) and mixtures of low concentration (CO2-limonene). For the implementation of the control system an expert system shell (CHRONOS?) was used. 相似文献
72.
ASSANN SIDAOUI ZDENEK BINDER RENÉ PERRET 《International journal of systems science》2013,44(8):1379-1385
An alternative hierarchical optimization algorithm obtained by combining a double-loop iterative strategy with an efficient coordination task is proposed. The new algorithm derived from the tracking method (Sidaoui et al. 1989, 1991) is applicable to non-convex problems and has the advantage of giving a better rate of convergence. Simulation results are given and compared with the original algorithm, indicating the superiority of the new approach for the example considered. 相似文献
73.
74.
A. L. CortÉs M. A. Soriano A. Maestro Corresponding author A. M. Casas 《International journal of remote sensing》2013,34(22):4325-4345
A lineament analysis of the Duero Basin (north Spain) suggests that cover rocks have been influenced by a previously fractured basement in sediment cover with little deformation. The Duero Basin is covered with horizontal Neogene rocks (mainly sandstones, shales and limestones) with a total outcropping area of about 50?000?km2 and a maximum thickness of 300?m. The only structures found within the Neogene are map-scale monoclines near the basin margins, and joints and faults, most of them without significant displacement. From the analysis of a Landsat Thematic Mapper (TM) scene, lineaments were mapped at the eastern half of the Duero Basin. The orientation frequency of lineaments shows an absolute maximum NE–SW to ENE–WSW, with several sub-maxima oriented E–W, NW–SE and WNW–ESE. These fracture directions controlled most of the present-day fluvial network. Within the Palaeozoic and Mesozoic rocks cropping out at the basin margins the orientation of lineaments corresponds with that of mappable faults, particularly in the Palaeozoic basement. The zones with maximum density of lineaments are associated with map-scale WNW–ESE thrusts and folds located below the horizontal Neogene. The origin of the main fracture systems in the Neogene rocks of the Duero Basin appears to be controlled by older structures, namely the NE–SW faults that cross-cut the granitic and gneissic basement of the Duero Basin and its southern and western margins. These faults are late Variscan (probably Permian) in origin and were reactivated during the Mesozoic and the Cenozoic. Their activity in Miocene and post-Miocene times is related to strike-slip and extensional movements linked to the recent intraplate stress field in the Iberian Peninsula. 相似文献
75.
Laure Berti-Équille 《Knowledge and Information Systems》2007,11(2):191-215
The quality of discovered association rules is commonly evaluated by interestingness measures (commonly support and confidence)
with the purpose of supplying indicators to the user in the understanding and use of the new discovered knowledge. Low-quality
datasets have a very bad impact over the quality of the discovered association rules, and one might legitimately wonder if
a so-called “interesting” rule noted LHS→ RHS is meaningful when 30% of the LHS data are not up-to-date anymore, 20% of the RHS data are not accurate, and 15% of the LHS data come from a data source that is well-known for its bad credibility. This paper presents an overview of data quality
characterization and management techniques that can be advantageously employed for improving the quality awareness of the
knowledge discovery and data mining processes. We propose to integrate data quality indicators for quality aware association
rule mining. We propose a cost-based probabilistic model for selecting legitimately interesting rules. Experiments on the challenging KDD-Cup-98 datasets show that variations on data quality have a great impact on the
cost and quality of discovered association rules and confirm our approach for the integrated management of data quality indicators
into the KDD process that ensure the quality of data mining results. 相似文献
76.
The polycyclic aromatic hydrocarbon (PAH), chrysene, was linked to the solid support TentaGel S-NH2 via a linker by means of synthesis. The resulting product 4-(chrysene-1-yloxy)-N-(TentaGel S)butanamide (4) was then evaluated for its ability to isolate PAHs from solution by means of π-π-interactions. 相似文献
77.
A. M. Éminov G. N. Maslennikova A. K. Abdurakhmanov Z. R. Kadyrova I. R. Baizhanov 《Glass and Ceramics》2001,58(9-10):315-316
It is demonstrated that the Sultan-Uvaiskoe deposit (Uzbekistan) is a promising source of high-quality kaolin for production of fine ceramics and refractories. 相似文献
78.
79.
K. K. Éidukyavichus V. R. Matseikene V. V. Balkyavichus A. A. Shpokauskas A. A. Laukaitis L. Yu. Kunskaite 《Glass and Ceramics》2004,61(3-4):77-80
The results of studying the possibility of using cullet of different chemical compositions accumulated at dumping grounds for foam glass production are described. It is established that sodium silicate introduced into cullet in the form of water glass partly destroys milled cullet and homogenizes the chemical composition of the batch and its most significant technological properties. Due to the chemical reaction between water glass and the surface of milled cullet particles, silicates are formed containing bound water, which is released at high temperatures (600 – 620°C) and facilitates frothing of foam glass. Water glass in a batch increases the quantity of the vitreous phase and decreases the propensity of glass for crystallization. 相似文献
80.
ABSTRACT This work presents a rotor resistance estimation algorithm. The estimation process is based on a recursive least squares method. It is applied to a speed sensorless induction motor drive scheme in order to implement slip adaptation. A discrete approach is considered in which an induction motor model written in form of difference equations is used by the estimation algorithm. All the associated mathematical developments are shown. Simulation results are used to verify the performance of the proposed rotor resistance estimator. 相似文献