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981.
Laura Hollink Véronique Malaisé Guus Schreiber 《Multimedia Tools and Applications》2010,49(1):235-257
It is common practice in audiovisual archives to disclose documents using metadata from a structured vocabulary or thesaurus.
Many of these thesauri have limited or no structure. The objective of this paper is to find out whether retrieval of audiovisual
resources from a collection indexed with an in-house thesaurus can be improved by enriching the thesaurus structure. We propose
a method to add structure to a thesaurus by anchoring it to an external, semantically richer thesaurus. We investigate the
added value of this enrichment for retrieval purposes. We first anchor the thesaurus to an external resource, WordNet. From
this anchoring we infer relations between pairs of terms in the thesaurus that were previously unrelated. We employ the enriched
thesaurus in a retrieval experiment on a TRECVID 2007 dataset. The results are promising: with simple techniques we are able
to enrich a thesaurus in such a way that it adds to retrieval performance. 相似文献
982.
In last years, Face recognition based on 3D techniques is an emergent technology which has demonstrated better results than
conventional 2D approaches. Using texture (180° multi-view image) and depth maps is supposed to increase the robustness towards
the two main challenges in Face Recognition: Pose and illumination. Nevertheless, 3D data should be acquired under highly
controlled conditions and in most cases depends on the collaboration of the subject to be recognized. Thus, in applications
such as surveillance or control access points, this kind of 3D data may not be available during the recognition process. This
leads to a new paradigm using some mixed 2D-3D face recognition systems where 3D data is used in the training but either 2D
or 3D information can be used in the recognition depending on the scenario. Following this concept, where only part of the
information (partial concept) is used in the recognition, a novel method is presented in this work. This has been called Partial
Principal Component Analysis (P2CA) since they fuse the Partial concept with the fundamentals of the well known PCA algorithm. This strategy has been proven
to be very robust in pose variation scenarios showing that the 3D training process retains all the spatial information of
the face while the 2D picture effectively recovers the face information from the available data. Furthermore, in this work,
a novel approach for the automatic creation of 180° aligned cylindrical projected face images using nine different views is
presented. These face images are created by using a cylindrical approximation for the real object surface. The alignment is
done by applying first a global 2D affine transformation of the image, and afterward a local transformation of the desired
face features using a triangle mesh. This local alignment allows a closer look to the feature properties and not the differences.
Finally, these aligned face images are used for training a pose invariant face recognition approach (P2CA). 相似文献
983.
984.
Yamine Ait Ameur Frédéric Boniol Virginie Wiels 《International Journal on Software Tools for Technology Transfer (STTT)》2010,12(1):1-7
Nowadays, it is well accepted that the development of critical systems involves the use of formal methods. One of the major
fields where these methods made a lot of progress are the avionics, aerospace and more generally transport areas. Several
methods, tools and techniques have been applied for the development of such systems in different parts of the world, and they
have been actually put into practice during the development of specific aircraft programs. The aim of this introductory article
and of this STTT special issue is to propose a brief overview of the state-of-the-art of current researches in formal methods
applied to the development of avionics and aerospace systems and more broadly to take stock of the integration of formal methods
in the aerospace industry. 相似文献
985.
Rocío de Andrés José Luis García-Lapresta Luis Martínez 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2010,14(1):21-34
The performance appraisal is a relevant process to keep and improve the competitiveness of companies in nowadays. In spite
of this relevance, the current performance appraisal models are not sufficiently well-defined either designed for the evaluation
framework in which they are defined. This paper proposes a performance appraisal model where the assessments are modelled
by means of linguistic information provided by different sets of reviewers in order to manage the uncertainty and subjectivity
of such assessments. Therefore, the reviewers could express their assessments in different linguistic scales according to
their knowledge about the evaluated employees, defining a multi-granular linguistic evaluation framework. Additionally, the
proposed model will manage the multi-granular linguistic labels provided by appraisers in order to compute collective assessments
about the employees that will be used by the management team to make the final decision about them. 相似文献
986.
987.
Stéphane Zieba Philippe Polet Frédéric Vanderhaegen Serge Debernard 《Cognition, Technology & Work》2010,12(3):193-203
Unmanned ground vehicles tend to be more and more autonomous, but both complete teleoperation and full autonomy are not efficient
enough to deal with all possible situations. To be efficient, the human–robot system must be able to anticipate, react and
recover from errors of different kinds, i.e., to be resilient. From this observation, this paper proposes a survey on the
resilience of a human–machine system and the means to control the resilience. The resilience of a system can be defined as
the ability to maintain or recover a stable state when subject to disturbance. Adjustable autonomy and human–machine cooperation
are considered as means of resilience for the system. This paper then proposes three indicators to assess different meanings
of resilience of the system: foresight and avoidance of events, reaction to events and recovery from occurrence of events.
The third of these metrics takes into consideration the concept of affordances that allows a common representation for the
opportunities of action between the automated system and its environment. 相似文献
988.
Roberto Sanchez Geneviève Dauphin-Tanguy Xavier Guillaud Frédéric Colas 《Simulation Modelling Practice and Theory》2010,18(9):1185-1198
This paper proposes a model of a three phase electrical inverter with a LC output filter in delta connection used in a renewable energy supply system. The concept of inverse bond graph via bicausality is used for the control law design. The control law robustness is tested by connecting passive and active (induction machine) loads. 相似文献
989.
Adrià Junyent-Ferré Oriol Gomis-Bellmunt Andreas Sumper Marc Sala Montserrat Mata 《Simulation Modelling Practice and Theory》2010,18(9):1365-1381
The present paper deals with the modeling of wind turbine generation systems. The model of a doubly fed induction generator, along with the corresponding converter, crow bar protection and electrical grid is described. The different level control strategies both in normal operation and under voltage dig conditions are discussed, including speed control, torque and reactive power control for the rotor-side converter, reactive and DC voltage control for the grid-side converter and the corresponding current loops control. The results obtained with simulations are compared to experimental data obtained from voltage sags provoked to real wind turbines. 相似文献
990.