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排序方式: 共有3551条查询结果,搜索用时 15 毫秒
41.
Das Internet ist heute eine globale Infrastruktur, deren st?ndige Verfügbarkeit mehr oder weniger als gegeben angenommen wird.
Die Einführung neuer Technologien (z. B. Multicast, IPv6) in diese Infrastruktur erweist sich aus unterschiedlichen Gründen
als schwierig. Vielmehr haben sich Overlay-Netze in diesem Kontext als Innovationsmotor etabliert. Diese werden von Endger?ten
am Netzrand aufgespannt, ben?tigen somit keine neuen Komponenten in der Netzinfrastruktur und lassen sich selbstorganisierend
sowie skalierbar einsetzen. Interessant sind diese Eigenschaften auch für den Overlay-basierten Aufbau und Betrieb von Kommunikationsnetzen
an sich, mit dem Ziel, unbeeinflusst von Mobilit?t, Multi-Homing und Heterogenit?t der Protokolle und Zugangsnetze nahtlose
Konnektivit?t zwischen Endger?ten herzustellen. Dieser Artikel zeigt anhand von Beispielen auf, wie Overlays die Entwicklung
neuer Dienste im Internet vorantreiben k?nnen. Als Beispiel für eine Overlay-basierte Netzarchitektur, welche die Realisierung
neuer Dienste und Anwendungen erm?glicht, wird die Architektur zur Realisierung von Spontanen Virtuellen Netzen (SpoVNet) und deren Netzabstraktionsschicht ariba detailliert vorgestellt. 相似文献
42.
Anselm Grundhöfer Daniel Kurz Sebastian Thiele Oliver Bimber 《The Visual computer》2010,26(9):1167-1176
In this article we show how temporal backdrops that alternately change their color rapidly at recording rate can aid chroma
keying by transforming color spill into a neutral background illumination. Since the chosen colors sum up to white, the chromatic
(color) spill component is neutralized when integrating over both backdrop states. The ability to separate both states additionally
allows to compute high-quality alpha mattes. Besides the neutralization of color spill, our method is invariant to foreground
colors and supports applications with real-time demands. In this article, we explain different realizations of temporal backdrops
and describe how keying and color spill neutralization are carried out, how artifacts resulting from rapid motion can be reduced,
and how our approach can be implemented to be compatible with common real-time post-production pipelines. 相似文献
43.
Oliver Schreer Ingo Feldmann Isabel Alonso Mediavilla Pedro Concejero Abdul H. Sadka Mohammad Rafiq Swash Sergio Benini Riccardo Leonardi Tijana Janjusevic Ebroul Izquierdo 《Multimedia Tools and Applications》2010,48(1):23-49
Multimedia analysis and reuse of raw un-edited audio visual content known as rushes is gaining acceptance by a large number
of research labs and companies. A set of research projects are considering multimedia indexing, annotation, search and retrieval
in the context of European funded research, but only the FP6 project RUSHES is focusing on automatic semantic annotation,
indexing and retrieval of raw and un-edited audio-visual content. Even professional content creators and providers as well
as home-users are dealing with this type of content and therefore novel technologies for semantic search and retrieval are
required. In this paper, we present a summary of the most relevant achievements of the RUSHES project, focusing on specific
approaches for automatic annotation as well as the main features of the final RUSHES search engine. 相似文献
44.
With the advent of multi-core processors, desktop application developers must finally face parallel computing and its challenges.
A large portion of the computational load in a program rests within iterative computations. In object-oriented languages these
are commonly handled using iterators which are inadequate for parallel programming. This paper presents a powerful Parallel
Iterator concept to be used in object-oriented programs for the parallel traversal of a collection of elements. The Parallel
Iterator may be used with any collection type (even those inherently sequential) and it supports several scheduling schemes
which may even be decided dynamically at run-time. Some additional features are provided to allow early termination of parallel
loops, exception handling and a solution for performing reductions. With a slight contract modification, the Parallel Iterator
interface imitates that of the Java-style sequential iterator. All these features combine together to promote minimal, if
any, code restructuring. Along with the ease of use, the results reveal negligible overhead and the expected inherent speedup. 相似文献
45.
W. Clark K. Logan R. Luckin A. Mee & M. Oliver 《Journal of Computer Assisted Learning》2009,25(1):56-69
46.
Oliver Baur 《Computers & Geosciences》2009,35(3):548-556
Least-squares (LS) problems occur in almost every scientific and engineering discipline. Basically, they are generated by providing more observations than unknown parameters to be resolved. Appropriate LS solvers depend on both quality and computational issues. With regard to the latter, this paper focuses on the tailored parallel implementation of two LS solvers: the iterative LSQR method (substitutional for any Krylov-space method) and the “brute-force” inversion approach. Both implementations demonstrate very good scaling results in a parallel processing environment. Even so, the present investigations show that, from the computational and hardware point of view, iterative solvers outperform the “brute-force” approach. LSQR not only provides superior speed-up values; but, in addition, source code portability and hardware requirements are much more convenient for the iterative solver. These conclusions are drawn in the context of state-of-the-art terrestrial geopotential recovery with regard to the forthcoming Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite mission. 相似文献
47.
48.
Oliver Bendel 《AI & Society》2016,31(1):103-108
Ethics researches morality in respect to humans and animals. Usually, it implies human morality; therefore, the focus is on human–human relationships (generally in ethics) and human–animal relationships (in animal ethics). Ethics can also deal with the morality of machines such as unmanned aerial vehicles, robots and agents or of self-driving cars and computers in automated trading, in other words more or less autonomous systems and programs. Machine ethics almost exclusively concentrates on machine–human relationships rather than on machine–animal relationships. Before this background, this article contributes some basic considerations about the relationship between animal and machine ethics. 相似文献
49.
Large area forest stem volume mapping in the boreal zone using synergy of ERS-1/2 tandem coherence and MODIS vegetation continuous fields 总被引:3,自引:0,他引:3
ERS-1/2 tandem coherence was reported to have high potential for the mapping of boreal forest stem volume (e.g. Santoro et al., 2002, 2007a; Wagner et al., 2003; Askne & Santoro, 2005). Large-scale application of the data for forest stem volume mapping, however, is hindered by the variability of coherence with meteorological and environmental acquisition conditions. The traditional way of stem volume retrieval is based on the training of models, relating coherence to stem volume, with the aid of forest inventory data which is generally available for a few small test sites but not for large areas. In this paper a new approach is presented that allows model training using the MODIS Vegetation Continuous Fields canopy cover product (Hansen et al., 2003) without further need for ground data. A comparison of the new approach with the traditional regression-based and ground-data dependent model training is presented in this paper for a multi-seasonal ERS-1/2 tandem dataset covering several well known Central Siberian forest sites. As a test scenario for large-area application, the approach was applied to a multi-seasonal ERS-1/2 tandem dataset of 223 ERS-1 and ERS-2 image pairs covering Northeast China (~ 1.5 million km2) to map four stem volume classes (0-20, 20-50, 50-80, and > 80 m3/ha). 相似文献
50.