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71.
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The primary aims of this study were to establish a client injury baseline for the New Zealand adventure tourism and adventure sport sector, and to examine patterns and trends in claims for injury during participation in adventure activities. Content analysis of narrative text data for compensated injuries occurring in a place for recreation and sport over a 12-month period produced over 15,000 cases involving adventure tourism and adventure sport. As found in previous studies in New Zealand, highest claim counts were observed for activities that are often undertaken independently, rather than commercially. Horse riding, tramping, surfing and mountain biking were found to have highest claim counts, while hang gliding/paragliding/parasailing and jet boating injuries had highest claim costs, suggesting greatest injury severity. Highest claim incidence was observed for horse riding, with female claimants over-represented for this activity. Younger male claimants comprised the largest proportion of adventure injuries, and falls were the most common injury mechanism. 相似文献
73.
The early stages of creep cavitation in sintered alumina are characterized using small-angle neutron scattering (SANS). It is found that the initial cavity density is of the order of 1011 cm–3, and that the average initial pore is approximately 60 nm in radius. The incubation time for nucleating additional pores during subsequent creep is extremely short, in agreement with the theory based on the precipitation of grain-boundary diffusing vacancies. Pore density at constant stress and temperature is a linearly increasing function of time, as predicted by classical nucleation theory. However, a local stress of 10–2
E is required to achieve the measured nucleation rate. Cavities are observed to lie primarily on two-grain junctions in linear arrays, with an average cavity radius of approximately 60 nm. It is hypothesized that the cavities nucleate at grain boundary ledges which provide the necessary local stress concentrations. Calculation of the individual cavity growth rate yields a zero or near zero value. This suggests a rapid transient growth period following nucleation which quickly decreases to a negligible growth rate. 相似文献
74.
Bart Goethals Dominique Laurent Wim Le Page Cheikh Tidiane Dieng 《Knowledge and Information Systems》2012,33(3):655-684
We present an approach for mining frequent conjunctive in arbitrary relational databases. Our pattern class is the simple, but appealing subclass of simple conjunctive queries. Our algorithm, called Conqueror $^+$ , is capable of detecting previously unknown functional and inclusion dependencies that hold on the database relations as well as on joins of relations. These newly detected dependencies are then used to prune redundant queries. We propose an efficient database-oriented implementation of our algorithm using SQL and provide several promising experimental results. 相似文献
75.
Cardiac transplantation in perspective for the future. Survival, complications, rehabilitation, and cost 总被引:1,自引:0,他引:1
JL Pennock PE Oyer BA Reitz SW Jamieson CP Bieber J Wallwork EB Stinson NE Shumway 《Canadian Metallurgical Quarterly》1982,83(2):168-177
Two hundred twenty-seven cardiac transplant procedures have been performed in 206 patients from January, 1968, to April, 1981. Postoperative survival rates, calculated by the actuarial method for program years 1968 to 1973 (66 patients), are 44%, 33%, 27%, 21%, and 18% at 1, 2, 3, 4, and 5 years after transplantation, respectively. Postoperative survival rates for program years 1974 to 1981 (140 patients) are 63%, 55%, 51, 44%, and 39% at 1, 2, 3, 4, and 5 years after transplantation, respectively. This increase results primarily from improvement in survival achieved in the first 3 postoperative months (59% +/- 7%, 1968 to 1973, versus 80% +/- 40%, 1974 to 1980), reflecting improved patient management. Infection remains the primary cause of death following transplantation (76/131 patients, 58%), followed by acute rejection (24/181, 18.3%), graft arteriosclerosis (14/131, 10.7%), and malignancy (6/131, 4.6%). The development of graft arteriosclerosis has been examined in 85 one-year survivors studied by annual coronary arteriograms. Coronary lesions of varying severity have developed in 21 patients. HLA-A2 incompatibility was associated with a higher incidence of graft arteriosclerosis than was apparent for all other A locus incompatibilities (p less than 0.0003). Lymphoma has been shown to be associated with younger recipient age, a primary disease diagnosis of idiopathic cardiomyopathy, and retransplantation. One hundred six patients have survived at least 1 year after transplantation; 97% were in NYHA Class 1 at that time interval and 82% returned to employment or activity of choice. The longest survival time is new 11 years, 3 months. Cardiac transplantation can be considered "reasonable and therapeutic treatment to extend life" in selected individuals. 相似文献
76.
Point fingerprint: a new 3-D object representation scheme 总被引:1,自引:0,他引:1
Yiyong Sun Joonki Paik Koschan A. Page D.L. Abidi M.A. 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2003,33(4):712-717
This paper proposes a new, efficient surface representation method for surface matching. A feature carrier for a surface point, which is a set of two-dimensional (2-D) contours that are the projections of geodesic circles on the tangent plane, is generated. The carrier is named point fingerprint because its pattern is similar to human fingerprints and plays a role in discriminating surface points. Corresponding points on surfaces from different views are found by comparing their fingerprints. The point fingerprint is able to carry curvature, color, and other information which can improve matching accuracy, and the matching process is faster than 2-D image comparison. A novel candidate point selection method based on the fingerprint irregularity is introduced. Point fingerprint is successfully applied to pose estimation of real range data. 相似文献
77.
Chaney John M.; Mullins Larry L.; Wagner Janelle L.; Hommel Kevin A.; Page Melanie C.; Doppler Matthew J. 《Canadian Metallurgical Quarterly》2004,49(2):126
Objective: Examine longitudinal relationships between causal attributions and depression symptoms in adults with rheumatoid arthritis (RA). Study Design: Cross-lagged panel correlations tested the temporal precedence of attributions relative to depression symptoms over 1 year. Participants: Forty-two participants completed self-report instruments on 2 occasions. Main Outcome Measures: The Inventory to Diagnose Depression and the Attributional Style Questionnaire. Results: Time 1 attributions predicted increased levels of depression symptoms at Time 2 after perceived pain and disability were controlled: Time 1 depression symptoms were unrelated to Time 2 attributions. Cross-lagged correlation comparisons revealed statistical dominance for attribution-depression relationships relative to depression-attribution relationships. Conclusions: Results support cognitive diathesis conceptualizations of depression and support cognitive-behavioral treatments for depression in RA. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
78.
A system for the quantitative analysis of stereo-pairs of photomicrographs has been devised using a Commodore ‘PET’ microcomputer coupled to a digitizing pad, plotter and printer. The system need not use any form of stereo-viewer and does not require any particular alignment of the photographs. Height differences, derived from parallax measurements, can be obtained quickly even by operators who might normally experience difficulties with stereoscope-based systems due to either poor stereo vision or inexperience. Three-dimensional coordinates, input from point-pairs, are stored inside the computer and may be sorted to draw line profiles along any operator-selected line. Such profiles may be referred to either the projection of the median plane of the two images or rotated (‘levelled’) to the 0° tilt plane. The operation of the system is described and illustrated using both specially-constructed left- and right-hand ‘images’ from test contours and also real SEM stereo pairs. Finally, both the potential and limitations of such a system for development and application are discussed. 相似文献
79.
80.
Landslide susceptibility mapping of the Sea to Sky transportation corridor, British Columbia, Canada: comparison of two methods 总被引:1,自引:0,他引:1
A. Blais-Stevens P. Behnia M. Kremer A. Page R. Kung G. Bonham-Carter 《Bulletin of Engineering Geology and the Environment》2012,71(3):447-466
The Sea to Sky corridor stretches over a distance of 135?km into British Columbia’s Coast Mountains. The corridor has witnessed hundreds of historical and pre-historic landslides. In the last 154?years, 155 landslide events have been reported. The most common types of landslides are rockfalls and debris flows, which are small in volume, but can be quite damaging. These are more abundant in the southern part of the corridor where infrastructure is built close to steep slopes. Two different methods were adapted to create debris flow and rockfall/rock slide susceptibility maps. Both qualitative heuristic and fuzzy logic susceptibility maps showed a similar distribution of susceptibility zones, especially high susceptibility. Correlation of high susceptibility zones with occurrence of historical and mapped geological landslide events was very good. Success rate curves were calculated for extrapolated zones of initiation for debris flow and rockfall/rock slide deposits. Success rate curves were better for debris flow than rockfall/rockslide maps. 相似文献