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111.
In the context of an industrial project, we evaluated the implementation of the software of a casino slot machine. This software has a significant amount of crosscutting concerns that depend on and interact with each other as well as with the modular concerns. We therefore wished to express our design using an appropriate aspect-oriented modeling approach. We therefore evaluated three candidate methodologies: Theme/UML, WEAVR, and RAM to establish their suitability. Remarkably, only the last of the three has shown to allow an adequate expression of the interactions, albeit not fully explicit. The first two fall short because half of the interaction types cannot be expressed at all while the other half need to be expressed using a work-around that hides the intention of the design. Neither does RAM allow a fully explicit expression of interactions, but it would be the most adequate approach for the slot machine case. 相似文献
112.
113.
Equipment selection plays a major role in the performance of machining/assembly cells. Based on analytical algorithms, a decision support system (DSS) is developed to select machining centres and robots concurrently from the milieu available in the marketplace. The DSS evaluates the design and geometry of the mating parts that are to be processed and assembled by the cell. Accordingly, it recommends the machining centre and robot that maximize the cell's performance subject to various operational and budget constraints. 相似文献
114.
Gaëtan Compère Jean‐François Remacle Johan Jansson Johan Hoffman 《International journal for numerical methods in engineering》2010,82(7):843-867
In this paper, we identify and propose solutions for several issues encountered when designing a mesh adaptation package, such as mesh‐to‐mesh projections and mesh database design, and we describe an algorithm to integrate a mesh adaptation procedure in a physics solver. The open‐source MAdLib package is presented as an example of such a mesh adaptation library. A new technique combining global node repositioning and mesh optimization in order to perform arbitrarily large deformations is also proposed. We then present several test cases to evaluate the performances of the proposed techniques and to show their applicability to fluid–structure interaction problems with arbitrarily large deformations. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
115.
The non-stoichiometric sulfide mineral pyrrhotite (Fe(1?x)S), common to many nickel ore deposits, occurs in different crystallographic forms and compositions. A series of pyrrhotite samples derived from Canada, South Africa and Botswana whose mineralogy is well characterised, were selected here in order to develop the relationship between mineralogy and flotation performance. Using both oxygen uptake and microflotation tests, the behaviour of the different pyrrhotite types was compared in terms of the effect of pH and collector addition. Non-magnetic pyrrhotite was less reactive in terms of its oxygen uptake and showed the best collectorless flotation recovery. Magnetic pyrrhotite was more reactive and showed poor collectorless flotation performance that could be improved with the addition of xanthate collector, but only if it was not already passivated. These differences are interpreted to be a result of pyrrhotite mineralogy. This has implications that may aid the manipulation of pyrrhotite flotation performance in processing operations. 相似文献
116.
Johan Petit Philippe DethareAlessandra Sergent Robert MarinoMarie-Hélène Ritti Stéphane LandaisJean-Luc Lunel Sandrine Trombert 《Journal of the European Ceramic Society》2011,31(11):1957-1963
In this paper we present our results on the sintering of α alumina ceramics by hot isostatic pressing. It describes a simple method for obtaining precise relative density values on our almost 100% dense samples. Then, transparency results are discussed with respect to grain size and residual porosity measurements, comparing them to scattering calculations. Our results are not far from the best reported transmission values: almost 60% for a 1 mm thick sample. The other 40% diffuse light comes from the birefringence of alumina for the most part. However, they are transparent enough to see detailed structures at several kilometers through them. 相似文献
117.
Johan Plomp Mikko Heiskanen Mika Hillukkala Tapio Heikkilä Jari Rehu Niek Lambert Victor van Acht Tom Ahola 《International Journal of Wireless Information Networks》2011,18(4):280-294
In this paper, we highlight considerations for synchronization issues in body area networks. Requirements for the synchronization
accuracy in body area networks depend on the application at hand. Synchronization may be needed for power management, sample
ordering, calculation of stimulus responses and for sensor fusion. This paper provides a theoretical exercise to help understand
the accuracy required for typical human motion sensing. It gives an overview of various synchronisation strategies used and
implemented in prototype systems. Lessons learnt from practical implementations using Bluetooth, an IEEE 802.15.4 proprietary
network and Nanonet are presented to illustrate the principles involved. The discussion provides some considerations and the
requirements for typical WBAN applications. 相似文献
118.
Platinum (Pt) nanocrystals of cubic and octopod structures were synthesized via seed-mediated solvothermal growth with monoethanolamine as the solvent. The combination of nanocube and octopod structures was formed using 0.025 ml seeds loading, while increasing the seeds volume to 0.050 ml and 0.100 ml produced nanocube as the primary product. The octopod structure evolves from the overgrown nanocube via kinetic growth mechanism. Pt nanocube formed with 0.050 ml seeded solution has the potential to serve as a catalyst in formic acid oxidation by virtue of its high electrochemical surface area of 10.93 m2/g, over that of Pt black at 8.62 m2/g and resistance to poisonous CO. Nonetheless, it is less catalytically active in ethanol oxidation as depicted by the small electrochemical surface area of 8.64 m2/g and low current density in longer period. 相似文献
119.
120.
Stef KerkhofsHeiko Lipkens Firmin VelghePieter Verlooy Johan A. Martens 《Journal of food engineering》2011,106(1):35-39
Mayonnaise currently is produced using high shear stirrers. Here we present a new production method using a magnetic emulsification device. According to the new method a stable oil-in-water emulsion is formed by pumping the two immiscible liquids through a magnetohydrodynamic dispersion device consisting of a Venturi provided with an orthogonal permanent magnetic field. As a proof of concept, magnetically emulsified highly viscous mayonnaise was produced in a batch process and in a continuous process. The viscosity of the mayonnaise was significantly enhanced by applying the magnetic field. The oil droplet size distribution of mayonnaise produced using the magnetic emulsification method was similar to mayonnaise produced with conventional high shear mixers. In contrast to conventional processes no fast moving mixers were needed in this new mayonnaise production scheme. 相似文献