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221.
AbstractIn this conceptual paper, we develop a framework which identifies those elements of firms’ knowledge context which are important for innovation, and the mechanisms through which that knowledge impacts on firms’ innovation performance. We make four main contributions to the existing literature. First, our characterisation of knowledge context provides the basis for a more specific identification of which elements of firms’ knowledge environment are important for innovation, discriminating between spatial, sectoral and network influences. Second, we reflect the role of innovation ambition in shaping firms’ knowledge search strategies. Third, we differentiate between firms’ interactive and non-interactive knowledge search activities and recognise that these may be complemented by unanticipated and serendipitous knowledge spillovers. Finally, we employ the notion of encoding capacity to reflect firms’ internal ability to assimilate and apply external knowledge, and clarify its distinctiveness from the more general concept of absorptive capacity. Our framework provides an integrating mechanism for existing empirical studies, and suggests a number of new research directions related to the determinants of innovation performance and the heterogeneity of innovation outcomes. 相似文献
222.
Energy Storage: Confined Assembly of Hollow Carbon Spheres in Carbonaceous Nanotube: A Spheres‐in‐Tube Carbon Nanostructure with Hierarchical Porosity for High‐Performance Supercapacitor (Small 19/2018) 下载免费PDF全文
223.
Shen Lang Poudel Nirakar Gibson George N. Hou Bingya Chen Jihan Shi Haotian Guignon Ernest Page William D. Pilar Arturo Cronin Stephen B. 《Nano Research》2018,11(4):2310-2314
Nano Research - We report plasmon resonant excitation of hot electrons in a photodetector based on a metal/oxide/metal (Au/Al2O3/graphene) heterostructure. In this device, hot electrons, excited... 相似文献
224.
The classic hypoglossal transfer to the facial nerve is invariably followed by complications caused by tongue atrophy. In 1984, Terzis introduced the "baby-sitter" procedure which involved a formal cross-facial procedure, in addition to partial neurectomy of the hypoglossal nerve, and an end-to-side coaptation with the ipsilateral facial nerve. This reported study provides, for the first time, quantification of the number of hypoglossal motor fibers needed to successfully restore eye sphincter function, using an end-to-side coaptation with preservation of the tongue. Thirty adult Sprague-Dawley rats were divided into six groups: control, denervated, perineurial window, 20 percent partial neurectomy (PN), 40 percent PN, and 80 percent PN. The procedure involves interposing a nerve graft (saphenous) between the partially severed XII nerve and the upper zygomatic branch of the facial nerve. Evaluation of the behavioral data (blink reflex) revealed good-to-superb return of the blinking mechanism in the 40 percent group, without significant tongue atrophy. Electrophysiologic data in the 40 percent neurectomy group demonstrated superiority to the other groups. Quantitative axonal morphometry of the coaptation sites and graft, as well as motor end-plates of the orbicularis oculi muscle and tongue showed the 40 percent partial neurectomy group to be the optimal group. 相似文献
225.
226.
Developing the ability to recognize a landmark from a visual image of a robot's current location is a fundamental problem in robotics. We consider the problem of PAC-learning the concept class of geometric patterns where the target geometric pattern is a configuration ofk points on the real line. Each instance is a configuration ofn points on the real line, where it is labeled according to whether or not it visually resembles the target pattern. To capture the notion of visual resemblance we use the Hausdorff metric. Informally, two geometric patternsP andQ resemble each other under the Hausdorff metric if every point on one pattern is close to some point on the other pattern. We relate the concept class of geometric patterns to the landmark matching problem and then present a polynomial-time algorithm that PAC-learns the class of one-dimensional geometric patterns. We also present some experimental results on how our algorithm performs. 相似文献
227.
Stephen Gilmore L��szl�� G?nczy Nora Koch Philip Mayer Mirco Tribastone D��niel Varr�� 《Software and Systems Modeling》2011,10(3):287-311
Systems based on the service-oriented architecture (SOA) principles have become an important cornerstone of the development
of enterprise-scale software applications. They are characterized by separating functions into distinct software units, called
services, which can be published, requested and dynamically combined in the production of business applications. Service-oriented
systems (SOSs) promise high flexibility, improved maintainability, and simple re-use of functionality. Achieving these properties
requires an understanding not only of the individual artifacts of the system but also their integration. In this context,
non-functional aspects play an important role and should be analyzed and modeled as early as possible in the development cycle.
In this paper, we discuss modeling of non-functional aspects of service-oriented systems, and the use of these models for
analysis and deployment. Our contribution in this paper is threefold. First, we show how services and service compositions
may be modeled in UML by using a profile for SOA (UML4SOA) and how non-functional properties of service-oriented systems can
be represented using the non-functional extension of UML4SOA (UML4SOA-NFP) and the MARTE profile. This enables modeling of
performance, security and reliable messaging. Second, we discuss formal analysis of models which respect this design, in particular
we consider performance estimates and reliability analysis using the stochastically timed process algebra PEPA as the underlying
analytical engine. Last but not least, our models are the source for the application of deployment mechanisms which comprise
model-to-model and model-to-text transformations implemented in the framework VIATRA. All techniques presented in this work
are illustrated by a running example from an eUniversity case study. 相似文献
228.
Lynne Baillie Lee Morton David C. Moffat Stephen Uzor 《Personal and Ubiquitous Computing》2011,15(1):13-24
Location-based games offer opportunities for us to learn more about people’s interactions and feelings towards the environment
they are in as well as to understand more about the mental models and locations associated with known environments, e.g. a
university campus with its associations of learning. In our study, we wanted to manipulate the activities in a game to take
advantage of certain locations in the hope of producing certain emotional reactions. However, it is not enough to simply produce
these reactions; one must also have a way of capturing any emotions produced whether these are the ones expected or not. The
objective of this paper, therefore, was to trial a new methodology for location-based games that aims at capturing the players’
emotional reactions to the activities in a game whilst in certain locations. In order to test the methodology, we designed
a location-based game that can be played on any Bluetooth-enabled mobile phone that has an accelerometer. The game has been
designed to interweave with a persons’ normal activity. As a result, there is little distinction between gaming time and non-gaming
time. 相似文献
229.
230.
C. Melody Carswell Cindy H. Lio Martina I. Klein Duncan Clarke Stephen Strup 《Applied ergonomics》2010,42(1):138-145