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71.
72.
Results of a survey of 19 doctoral psychology programs indicate that the majority of faculty in university-affiliated free-standing professional programs are part-time, and their primary income and professional identity are outside the educational program. Questions are raised concerning faculty commitment to student education, financial viability and institutional stability, the history of free-standing schools in other professions, and whether psychology should continue to be based in the university. (4 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Varied rated noun imagery (I), rated adjective I, and noun-adjective order in a paired-associate (PA) learning task. 98 10th graders learned 2 PA lists, 1 with noun-adjective (N-A) pairs and 1 with adjective-noun (A-N) pairs. Within each list rated I of both nouns and adjectives was varied factorially. Both English- and French-speaking Ss learned the lists in their own languages. Results support the predictions from an hypothesis based on mediating imagery. N-A recall was superior to A-N recall for all combinations of word I, except when nouns were low and adjectives high in I. In the latter case, A-N recall was higher. This pattern was the same for both English- and French-speaking Ss. Results are interpreted as further evidence of the important role played by imagery in verbal learning. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Discrete Convolution in Power System Reliability 总被引:2,自引:0,他引:2
Allan R.N. da Silva A.M. Leite Abu-Nasser A.A. Burchett R.C. 《Reliability, IEEE Transactions on》1981,(5):452-456
This paper describes a general method for convolving discrete distributions using Fast Fourier Transforms. It can be used in evaluating reliability of any system involving discrete or discretised convolution. It has been used in power system studies to deduce capacity-outage probability tables and to solve probabilistic load flows. These studies have shown it to be much less time-consuming and more efficient than the conventional direct methods. The method is used in the paper to evaluate the loss of load probability of a generating system in order to demonstrate the method's application and inherent merits. 相似文献
75.
76.
Allan J. Easteal David J. Udy 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1973,23(12):865-870
Solutions of ilmenite (FeTiO3) and a titaniferous slag, in fused Li2O. 2B2O3 and Li2O. 4B2O3, yield on cooling compounds tentatively identified as LiFe2.5Ti3O9 and Li2Fe3Ti2.5O9 respectively. Both compounds are orthorhombic, and have the pseudobrookite structure. The ilmenite solutions yield, in addition, rutile (TiO2). The yield of rutile increases from about 1 to 24% (w/w) of the products, when the solvent is changed from Li2O. 2B2O3 to Li2O. 4B2O3. Substitution of K2O. 4B2O3 for the latter solvent decreases the yield of rutile to c. 10%. The yield of rutile is approximately in inverse proportion to the Lux—Flood basicity of the borate solvent. 相似文献
77.
Describes 2 experiments with 54 undergraduates in which pupillary activity was continuously photographed during mediator-formation and paired-associate (PA) learning tasks involving nouns as items. Abstractness-concreteness of the nouns and mediation instructions (imagery, verbal, or none) were varied. The magnitude and latency of pupillary dilation as well as task performance were measured. The PA recall data confirm previous findings in showing strong positive effects of concreteness, especially as a stimulus variable. Learning was generally best under the imagery mediation set, its superiority over the verbal mediation condition being greatest in the case of pairs with abstract stimulus members. Pupil size during learning was largest when no mediation instructions were given and when stimulus members were abstract, supporting an interpretation of pupillary dilation as an index of cognitive task difficulty. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Allan Borodin Michael J. Fischer David G. Kirkpatrick Nancy A. Lynch Martin Tompa 《Journal of Computer and System Sciences》1981,22(3):351-364
A model of computation is introduced which permits the analysis of both the time and space requirements of non-oblivious programs. Using this model, it is demonstrated that any algorithm for sorting n inputs which is based on comparisons of individual inputs requires time-space product proportional to n2. 相似文献
79.
Previous research has classified the occupation of sheep shearing as heavy work where shearers flex their spine and hips for long periods of time, handle awkward loads and expend high amounts of energy. The aim of this research was to investigate the magnitude of spinal forces produced during the shearing phase of the work and to determine whether the use of a commercially available back support harness would reduce these forces. Following discussion on task complexity and risk of back injury with senior shearing instructors, three component tasks of the shearing phase were identified as posing high risk of injury and were prioritized for primary analysis. Although the dragging out of a sheep in preparation for shearing and an unexpected loss of animal control were also identified as being of high risk, technological and instrumentation difficulties precluded their analysis. Twelve experienced shearers were videotaped while shearing with and without the use of a back harness. Surface mounted retro-reflective markers placed on the trunk defined three linked segments: Pelvis, Lumbar and Head, Arms, and Upper Trunk (HAUT). A 3D, link segment, top down, inverse dynamics approach was used to describe the motion and to estimate forces involved during the identified tasks of shearing. The spinal force/time profiles of this sample of shearers demonstrated large compressive and shear forces for all three tasks that are close to the NIOSH and University of Waterloo action limits for compressive and shear forces respectively (McGill 1997, Yingling and McGill 1999, Marras 2000). The use of the back support harness reduced these forces by substantial and statistically significant amounts. This effect was consistent across all three tasks. The results of this study demonstrate the production of high levels of compressive and shear forces within the spine of shearers during the three shearing tasks studied and that the use of a back support harness can substantially reduce these forces. Therefore the use of a back harness may reduce the cumulative load on the spine during shearing thereby moderating damage to the articular structures. However it is not known whether the harness would protect the spine from a sudden or unexpected force. 相似文献
80.
We apply and extend the priority algorithm framework
introduced by Borodin, Nielsen, and
Rackoff to define greedy-like algorithms for the
(uncapacitated) facility location problems and set cover problems. These problems
have been the focus of extensive research from the point of view of
approximation algorithms and for both problems greedy-like algorithms
have been proposed and analyzed. The priority algorithm definitions
are general enough to capture a broad class of algorithms that can be characterized
as greedy-like while still possible to derive non-trivial
lower bounds on the approximability of the problems
by algorithms in such a class.
Our results are orthogonal to
complexity considerations, and hence apply to algorithms that
are not necessarily polynomial time. 相似文献