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131.
The purpose of this laboratory study was to evaluate the possible differences in motor strategies to a new standardized low-load repetitive work task in between healthy experienced workers and a reference group. Work task event duration, i.e. working rhythm, cutting forces, surface electromyographic (EMG) activity from four shoulder muscles, postural activity, and arm and trunk movements in 3D were recorded during low-load repetitive work simulation. The experienced group showed lower EMG activity and frequency contents (P<0.05), more abducted position of the upper arm and forward flexion of the trunk prior to work simulation (P<0.05), and increased arm and trunk range of motion (P<0.05) compared with the reference group. The results highlight that experienced butchers have a different motor strategy compared with a reference group, i.e. more variable form of coordination pattern. Furthermore, the initial implementation of a possible protective motor strategy by experienced workers might be a very important prognostic factor. 相似文献
132.
Florent?MassegliaEmail author Maguelonne?Teisseire Pascal?Poncelet 《Knowledge and Information Systems》2003,5(4):439-465
The behavior of the users of a website may change so quickly that it becomes a real challenge to attempt to make predictions according to the frequent patterns coming from the analysis of an access log file. In order to reduce the obsolescence of behavioral patterns as much as possible, the ideal method would provide frequent patterns in real time, making the result immediately available. In this paper, we propose a method for finding frequent behavioral patterns in real time, whatever the number of connected users. Considering how fast frequent behavior patterns may have changed since the time the access log file was analyzed, this result thus provides completely appropriate navigation schemata for predicting user behavior. Based on a distributed heuristic, our method also tackles and provides answers to several problems within the framework of data mining: the discovery of interesting zones (a large number of frequent patterns concentrated over a period of time, or super-frequent patterns), discovering very long sequential patterns and interactive data mining (on-the-fly modification of the minimum support). 相似文献
133.
We present an all-numeric multiplexing/demultiplexing technique for digitally recorded holograms that allow the simultaneous determination of the in-plane and the out-of-plane components of the displacement vector of an object submitted to some loading. The twin-sensitivity measurement is obtained from two different illumination directions that give two sensitivity vectors. The spatial multiplexing is achieved by an incoherent mixing of two duplets of coherent waves that produce holograms carried with orthogonal polarized reference waves. The spatial demultiplexing uses the autocorrelation function of the multiplexed holograms as a position estimator. The estimator then enables the determination of the pixel-to-pixel correspondence between the holograms for the double component determination. Results of the experiment are presented. 相似文献
134.
Madeleine Pascal 《Multibody System Dynamics》2001,5(4):315-334
Some open questions arising in the dynamical formulation ofsystems of hinge-connected flexible bodies are discussed. The first one deals with the choice of the floating reference frame associated to abody undergoing large rigid body motions but small elastic deformations.The second one concerns the so-called geometric stiffening (orcentrifugal stiffening) effects. The last problem is concerned with theeventual appearance of higher-order terms in the kinetic energy of thesystem for large rates and large accelerations. 相似文献
135.
Slobodan Ilić Mathieu Salzmann Pascal Fua 《International Journal of Computer Vision》2007,72(2):159-178
Using silhouettes in uncontrolled environments typically requires handling occlusions as well as changing or cluttered backgrounds,
which limits the applicability of most silhouette based methods. For the purpose of 3-D shape modeling, we show that representing
generic 3-D surfaces as implicit surfaces lets us effectively address these issues.
This desirable behavior is completely independent from the way the surface deformations are parame-trized. To show this, we
demonstrate our technique in three very different cases: Modeling the deformations of a piece of paper represented by an ordinary
triangulated mesh; reconstruction and tracking a person’s shoulders whose deformations are expressed in terms of Dirichlet
Free Form Deformations; reconstructing the shape of a human face parametrized in terms of a Principal Component Analysis model.
Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users.
This work was supported in part by the Swiss National Science Foundation 相似文献
136.
Harunori Yoshikawa Pascal Kurowski Philippe Petitjeans Farzam Zoueshtiagh Hervé Caps 《Microgravity science and technology》2007,19(3-4):155-156
The response of an air bubble surrounded by a liquid in a sealed cell submitted to vibrations was investigated experimentally under microgravity conditions and compared to experiments under normal gravity conditions. As in normal gravity [1], it was observed that the bubble split into smaller parts when the acceleration of the vibrations reached a threshold. This threshold in microgravity is substantially smaller than that in normal gravity. Experimental results are presented in terms of an acceleration based Bond number which has been found to characterize the bubble behaviour in the laboratory experiments [1]. 相似文献
137.
Emmanuel Defaÿ David Wolozan Jean-Pierre Blanc Emmanuelle Serret Pierre Garrec Sophie Verrun Denis Pellissier Philippe Delpech Julie Guillan Bernard Andr Laurent Ulmer Marc Aïd Pascal Ancey 《Solid-state electronics》2007,51(11-12):1624
This paper describes realization and characterization of SrTiO3 (STO) high K MIM capacitors above BiCMOS integrated circuit (IC). These capacitances are connected to IC and are used as coupling capacitors in order to realize a high pass filter. Surface capacitance achieved is 10 nF/mm2 with capacitance value of 1.2 nF. The process for STO MIM fabrication does not exceed 400 °C, which is compatible with interconnections. Typical K and dielectric losses values obtained are, respectively 110% and 2%. Yield obtained reaches 83% for capacitors. A functional high pass filter using these STO capacitors was realized in this study. It exhibits a cut-off frequency at 6.5 kHz and a constant gain at higher frequencies of −1.3 dB. 相似文献
138.
Hameed Hussain Saif Ur Rehman Malik Abdul Hameed Samee Ullah Khan Gage Bickler Nasro Min-Allah Muhammad Bilal Qureshi Limin Zhang Wang Yongji Nasir Ghani Joanna Kolodziej Albert Y. Zomaya Cheng-Zhong Xu Pavan Balaji Abhinav Vishnu Fredric Pinel Johnatan E. Pecero Dzmitry Kliazovich Pascal Bouvry Hongxiang Li Lizhe Wang Dan Chen Ammar Rayes 《Parallel Computing》2013
An efficient resource allocation is a fundamental requirement in high performance computing (HPC) systems. Many projects are dedicated to large-scale distributed computing systems that have designed and developed resource allocation mechanisms with a variety of architectures and services. In our study, through analysis, a comprehensive survey for describing resource allocation in various HPCs is reported. The aim of the work is to aggregate under a joint framework, the existing solutions for HPC to provide a thorough analysis and characteristics of the resource management and allocation strategies. Resource allocation mechanisms and strategies play a vital role towards the performance improvement of all the HPCs classifications. Therefore, a comprehensive discussion of widely used resource allocation strategies deployed in HPC environment is required, which is one of the motivations of this survey. Moreover, we have classified the HPC systems into three broad categories, namely: (a) cluster, (b) grid, and (c) cloud systems and define the characteristics of each class by extracting sets of common attributes. All of the aforementioned systems are cataloged into pure software and hybrid/hardware solutions. The system classification is used to identify approaches followed by the implementation of existing resource allocation strategies that are widely presented in the literature. 相似文献
139.
C. Thanga Raj Radha Thangaraj Millie Pant Pascal Bouvry Ajith Abraham 《Applied Artificial Intelligence》2013,27(9):809-831
This article deals with the design optimization of a squirrel-cage three-phase induction motor, selected as the driving power of spinning machines in the textile industry, using three newly developed versions of differential evolution (DE) algorithms called modified DE versions (CMDE, GMDE, and LMDE). Efficiency, which decides the operating or running cost of the motor (industry), is considered as the objective function. First, the algorithms are applied to design a general purpose motor with seven variables and nine performance-related parameters with their nominal values as constraints. To make the machine feasible, practically acceptable to serve in textile industries, and less costly to operate, certain constraints are modified in accordance with the demands of the spinning application. Comparison of the optimum designs with the industrial (existing) motor reveals that the motor designed by the proposed algorithms consumes less power input. 相似文献
140.
Vincent Wawrzyniak Hervé Piégay Pascal Allemand Lise Vaudor Philippe Grandjean 《International journal of remote sensing》2013,34(13):4812-4831
Braided rivers exhibit high spatial thermal heterogeneity that is difficult to understand using only in situ measurements. In this summer study, we used a drone and a powered paraglider to acquire very high spatial resolution (14–27 cm) thermal infrared (TIR) images of nine braided reaches located in the French Alps. We applied atmospheric corrections to TIR images and calibrated them based on in situ data. To characterize spatial and temporal thermal patterns, three temporal approaches were applied. A single survey of each site was performed to comparatively explore the nine braided reaches. Three reaches were imaged twice, in 2010 and 2011, to explore inter-annual variability. Finally, two reaches were selected for an intra-day survey for which four and three flights, respectively, were realized within one day. We reported two types of thermal patterns in braided reaches, the first showing very low thermal variability throughout the day. This low variability was linked to the low diversity found in the aquatic habitat, notably due to proglacial regimes with high summer flows which homogenize water temperatures. The second type exhibited a higher thermal variability with changes during the day. The temperature of flowing channels changed during the daytime according to air temperature. In contrast, the temperature of channels downstream connected to the main network exhibited smaller changes, which created thermal variability over space and time associated with hyporheic or phreatic flows. Non-proglacial and proglacial reaches behaved differently according to air temperature. Proglacial reaches were colder and less sensitive to air temperature in comparison with non-proglacial reaches. These findings allow for a prediction of habitat diversity from temperature heterogeneity based on time and the proportion of ponds, alluvial, and groundwater channels. 相似文献