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61.
Synthesis, photophysical, and electrochemical characterizations of iridium‐complex anchored polyhedral oligomeric silsesquioxane (POSS) macromolecules are reported. Monochromatic organic light‐emitting devices based on these phosphorescent POSS materials show peak external quantum efficiencies in the range of 5–9%, which can be driven at a voltage less than 10 V for a luminance of 1000 cd m?2. The white‐emitting devices with POSS emitters show an external quantum efficiency of 8%, a power efficiency of 8.1 lm W?1, and Commission International de'lÉclairage coordinates of (0.36, 0.39) at 1000 cd m?2. Encouraging efficiency is achieved in the devices based on hole‐transporting and Ir‐complex moieties dual‐functionalized POSS materials without using host materials, demonstrating that triplet‐dye and carrier‐transporting moieties functionalized POSS material is a viable approach for the development of solution‐processable electrophosphorescent devices.  相似文献   
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The construction and the performance of a time-to-amplitude converter equipped with constant fraction discriminators is described. The TAC consists of digital and analog parts which are constructed on two printed circuit boards, both of which are located in a single width NIM module. The dead time of the TAC for a start pulse which is not followed by a stop pulse within the time range of the device (~ 100 ns) is only ~ 100 ns, which enables one to avoid counting rate saturation even with a high random input signal rate.The differential and integral nonlinearities of the TAC are better than ± 1.5% and 0.0.5%, respectively. The resolution for input timing pulses of constant shape is 20 ps (fwhm), and less than 10 ps (fwhm) with a modification in the digital part. The walk error of the constant fraction timing discriminators is presented and various parameters affecting it are discussed. The effect of the various disturbances in linearity caused by the fast ECL logic and their minimization are also discussed.The time-to-amplitude converter has been used in positron lifetime studies and for laser range finding.  相似文献   
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Objects with many concavities are difficult to acquire using laser scanners. The highly concave areas are hard to access by a scanner due to occlusions by other components of the object. The resulting point scan typically suffers from large amounts of missing data. Methods that use surface‐based priors rely on local surface estimates and perform well only when filling small holes. When the holes become large, the reconstruction problem becomes severely under‐constrained, which necessitates the use of additional reconstruction priors. In this paper, we introduce weak volumetric priors which assume that the volume of a shape varies smoothly and that each point cloud sample is visible from outside the shape. Specifically, the union of view‐rays given by the scanner implicitly carves the exterior volume, while volumetric smoothness regularizes the internal volume. We incorporate these priors into a surface evolution framework where a new energy term defined by volumetric smoothness is introduced to handle large amount of missing data. We demonstrate the effectiveness of our method on objects exhibiting deep concavities, and show its general applicability over a broader spectrum of geometric scenario.  相似文献   
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We present a Brownian Dynamics model of biological molecule separation in periodic nanofilter arrays. The biological molecules are modeled using the Worm-Like-Chain model with Hydrodynamic Interactions. We focus on short dsDNA molecules; this places the separation process either in the Ogston sieving regime or the transition region between Ogston sieving and entropic trapping. Our simulation results are validated using the experimental results of Fu et al. (Phys Rev Lett 97:018103, 2006); particular attention is paid to the model’s ability to quantitatively capture experimental results using realistic values of all physical parameters. Our simulation results showed that molecule mobility is sensitive to the device geometry. Moreover, our model is used for validating the theoretical prediction of Li et al. (Anal Bioanal Chem 394:427–435, 2009) who proposed a separation process featuring an asymmetric device and an electric field of alternating polarity. Good agreement is found between our simulation results and the predictions of the theoretical model of Li et al.  相似文献   
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In this work, the consequences of using several different discrete element granular assemblies for the representation of the microscale structure, in the framework of multiscale modeling, have been investigated. The adopted modeling approach couples, through computational homogenization, a macroscale continuum with microscale discrete simulations. Several granular assemblies were used depending on the location in the macroscale finite element mesh. The different assemblies were prepared independently as being representative of the same material, but their geometrical differences imply slight differences in their response to mechanical loading. The role played by the micro‐assemblies, with weaker macroscopic mechanical properties, on the initiation of strain localization in biaxial compression tests is demonstrated and illustrated by numerical modeling of different macroscale configurations. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Construction companies are increasingly being challenged to transfer and use new technology. However, little investigation has been undertaken on technology transfer from the perspective of the small construction company. A contribution to this underdeveloped area is based on results from an interview survey of seven small UK construction companies. The results stress that the technology which small construction companies tend to transfer more successfully is that which can contribute to the business in a quick, tangible fashion, and which can fit into existing organizational capabilities. Any technology that is too far removed from this ‘comfort zone’ is seen to require too much investment and to contain too much risk, and thus tends to be intuitively and swiftly sifted out. This is in marked contrast to the relevant literature that depicts large companies operating in more complex networks, drawing upon them for new tacit and explicit technologies that support more long-term, formal technology strategies, and which often complement some form of specialized internal research and development capability. The implication for policy is that any technology transfer initiatives need to appreciate and actively manage the different motivations and capabilities of small and large construction companies to absorb and use new technology.

Les entreprises de construction sont de plus en plus appelées à résoudre des questions de transfert et d'utilisation de technologies nouvelles. En revanche, on s'est peu intéressé au point de vue des petites entreprises de ce secteur sur les transferts de technologies. Cette contribution à ce secteur peu développé repose sur les résultats d'une enquête menée en Grande Bretagne auprès de sept petites entreprises de construction. Il en ressort que les technologies que les petites entreprises ont tendance à transférer le mieux sont celles qui peuvent contribuer au développement rapide et tangible des affaires et qui peuvent s'intégrer dans une structure organisationnelle existante. Toute technologie qui s'écarte de trop de cette ‘zone de confort’ est considérée comme nécessitant un investissement trop lourd et présenter trop de risques et a donc tendance à être intuitivement et rapidement mise à l'écart. Cette constatation est en complète opposition avec la littérature qui décrit de grandes entreprises opérant dans le cadre de réseaux plus complexes, attirant vers elles de nouvelles technologies tacites et explicites, compatibles avec des stratégies technologiques officielles à plus long terme et qui, souvent, complètent des formes de recherche interne spécialisée et de capacité de développement. L'implication politique est que toute initiative de transfert de technologie nécessite d'évaluer et de gérer activement les différentes motivations et capacités des petites et grandes entreprises de construction dans leur aptitude à absorber et utiliser de nouvelles technologies.  相似文献   
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