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71.
Healey C Kocherlakota S Rao V Mehta R St Amant R 《IEEE transactions on visualization and computer graphics》2008,14(2):396-411
This paper describes the integration of perceptual guidelines from human vision with an AI-based mixed-initiative search strategy. The result is a visualization assistant called ViA, a system that collaborates with its users to identify perceptually salient visualizations for large, multidimensional datasets. ViA applies knowledge of low-level human vision to: (1) evaluate the effectiveness of a particular visualization for a given dataset and analysis tasks; and (2) rapidly direct its search towards new visualizations that are most likely to offer improvements over those seen to date. Context, domain expertise, and a high-level understanding of a dataset are critical to identifying effective visualizations. We apply a mixed-initiative strategy that allows ViA and its users to share their different strengths and continually improve ViA's understanding of a user's preferences. We visualize historical weather conditions to compare ViA's search strategy to exhaustive analysis, simulated annealing, and reactive tabu search, and to measure the improvement provided by mixed-initiative interaction. We also visualize intelligent agents competing in a simulated online auction to evaluate ViA's perceptual guidelines. Results from each study are positive, suggesting that ViA can construct high-quality visualizations for a range of real-world datasets. 相似文献
72.
Maria Koutantji Peter McCulloch Shabnam Undre Sanjay Gautama Simon Cunniffe Nick Sevdalis Rachel Davis Piers Thomas Charles Vincent Ara Darzi 《Cognition, Technology & Work》2008,10(4):275-285
We developed a module for surgical team training using briefings in simulated crisis scenarios and here we report preliminary
findings. Nine surgical teams (34 trainees) participated in a pre-training simulation, followed by an interactive workshop
on briefing and checklists, and then a post-training simulation. Both technical and non-technical skills were assessed via
observation during simulations by expert trainers who provided feedback on performances at the end of simulation. Trainees
also reported their attitudes to briefings and evaluated the training. Pre-training attitudes to briefing were positive, some
of which improved post-training and trainees’ evaluation of the training was positive. Surgeons’ technical skill improved
significantly post-training, but their decision-making skill was rated lower than other non-technical skills, compared to
other trainees. The training did not appear to greatly improve non-technical skill performance. Training surgical teams in
simulation is feasible but much more work is needed on measurement development and training strategy to confirm its efficacy
and utility. 相似文献
73.
74.
Ada Gavrilovska Sanjay Kumar Srikanth Sundaragopalan Karsten Schwan 《Multimedia Tools and Applications》2007,34(2):179-200
Increased network speeds coupled with new services delivered via the Internet have increased the demand for intelligence and
flexibility in network systems. This paper argues that both can be provided by new hardware platforms comprised of heterogeneous
multi-core systems with specialized communication support. We present and evaluate an experimental network service platform
that uses an emergent class of devices—network processors—as its communication support, coupled via a dedicated interconnect
to a host processor acting as a computational core. A software infrastructure spanning both enables the dynamic creation of
application-specific services on the network processor, mediated by middleware and controlled by kernel-level communication
support. Experimental evaluations use a Pentium IV-based computational core coupled with an IXP 2400 network processor. The
sample application services run on both include an image manipulation application and application-level multicasting.
相似文献
Karsten SchwanEmail: |
75.
76.
Pd supported on KL zeolite has been studied by temperature programmed reduction (TPR) and electron paramagnetic resonance (EPR) spectroscopy. It has been found that upon calcination in pure oxygen Pd3+ and Pd2+ ions are formed; the Pd3+ ions are identified by their EPR signal. As Pd3+ ions in the cancrinite cages are difficult to reduce, the H2 consumption in conventional TPR is below the stoichiometric amount. 相似文献
77.
Soham Uday Mehta Ravi Ramamoorthi Mark Meyer Christophe Hery 《Computer Graphics Forum》2012,31(4):1501-1508
Environment‐mapped rendering of Lambertian isotropic surfaces is common, and a popular technique is to use a quadratic spherical harmonic expansion. This compact irradiance map representation is widely adopted in interactive applications like video games. However, many materials are anisotropic, and shading is determined by the local tangent direction, rather than the surface normal. Even for visualization and illustration, it is increasingly common to define a tangent vector field, and use anisotropic shading. In this paper, we extend spherical harmonic irradiance maps to anisotropic surfaces, replacing Lambertian reflectance with the diffuse term of the popular Kajiya‐Kay model. We show that there is a direct analogy, with the surface normal replaced by the tangent. Our main contribution is an analytic formula for the diffuse Kajiya‐Kay BRDF in terms of spherical harmonics; this derivation is more complicated than for the standard diffuse lobe. We show that the terms decay even more rapidly than for Lambertian reflectance, going as l–3, where l is the spherical harmonic order, and with only 6 terms (l = 0 and l = 2) capturing 99.8% of the energy. Existing code for irradiance environment maps can be trivially adapted for real‐time rendering with tangent irradiance maps. We also demonstrate an application to offline rendering of the diffuse component of fibers, using our formula as a control variate for Monte Carlo sampling. 相似文献
78.
Ashish Mehta James Geller Yehoshua Perl Erich Neuhold 《The VLDB Journal The International Journal on Very Large Data Bases》1998,7(1):25-47
A path-method is used as a mechanism in object-oriented databases (OODBs) to retrieve or to update information relevant to one class that
is not stored with that class but with some other class. A path-method is a method which traverses from one class through
a chain of connections between classes and accesses information at another class. However, it is a difficult task for a casual
user or even an application programmer to write path-methods to facilitate queries. This is because it might require comprehensive
knowledge of many classes of the conceptual schema that are not directly involved in the query, and therefore may not even
be included in a user's (incomplete) view about the contents of the database. We have developed a system, called path-method generator (PMG), which generates path-methods automatically according to a user's database-manipulating requests. The PMG offers the
user one of the possible path-methods and the user verifies from his knowledge of the intended purpose of the request whether
that path-method is the desired one. If the path method is rejected, then the user can utilize his now increased knowledge
about the database to request (with additional parameters given) another offer from the PMG. The PMG is based on access weights attached to the connections between classes and precomputed access relevance between every pair of classes of the OODB. Specific rules for access weight assignment and algorithms for computing access
relevance appeared in our previous papers [MGPF92, MGPF93, MGPF96]. In this paper, we present a variety of traversal algorithms
based on access weights and precomputed access relevance. Experiments identify some of these algorithms as very successful
in generating most desired path-methods. The PMG system utilizes these successful algorithms and is thus an efficient tool
for aiding the user with the difficult task of querying and updating a large OODB.
Received July 19, 1993 / Accepted May 16, 1997 相似文献
79.
A two part probabilistic model for polycrystalline microstructures is described. The model utilizes a Poisson–Voronoi tessellation for the grain geometry and a vector random field model for the crystallographic orientation. The grain geometry model is calibrated to experimental data through the intensity of the Poisson point field underlying the Poisson–Voronoi tessellation and the orientation random field is calibrated to experimental data through its marginal distributions and second moment properties. Realizations of the random microstructure are generated by use of translation methods and are used, with simplified mechanical models, to investigate the problem of intergranular fracture. It is found that intergranular cracks exhibit some statistical properties of a scaled Brownian motion process. 相似文献
80.
Robin G. Qiu Sanjay Joshi Patrick McDonnell 《Journal of Intelligent Manufacturing》2004,15(5):579-591
By complying with the operational philosophy of virtual production lines, a back-end semiconductor manufacturing system can be controlled and managed with better reconfigurability. However, due to the absence of a fully-integrated information system and the gaining popularity of distributed computing, machine reconfiguration decisions are made by machine controllers on the shop floor where heterarchical control architecture is typically used. This research investigates how non-cooperative game theory could be applied for facilitating the decision process reconfiguration decision-making at the machine controller level as machines are competed by multiple jobs streams. This paper presents how material flow traffic can be better regulated in a reconfigurable manufacturing environment. A study using an industrial pilot system is discussed to demonstrate the applicability of the proposed approach, in which heuristics are used to determine the game specification. 相似文献