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71.
Michael Breuß Henning Zimmer Joachim Weickert 《Journal of Mathematical Imaging and Vision》2011,39(3):230-244
Optic flow and stereo reconstruction are important examples of correspondence problems in computer vision. Correspondence
problems have been studied for almost 30 years, and energy-based methods such as variational approaches have become popular
for solving this task. However, despite the long history of research in this field, only little attention has been paid to
the numerical approximation of derivatives that naturally occur in variational approaches. 相似文献
72.
Hinrich Henning Dr. 《真空研究与实践》2009,21(1):26-31
The Patented Inventions from Wolfgang Gaede from 1905 to 1945 The collection of Gaede's patents shows how successfully cooperation between science and industry could bee. Several up to now important inventions in vacuum technique have been made and this in sometimes hard and difficult circumstances. Even when Gaede has lost his chair at the university of Karlsruhe from illegal intrigues by the Nazis. 相似文献
73.
A continuous, non-invasive and objective measure of teamwork effectiveness could be very useful to the human factors design community. Social psychophysiological compliance (SPC), estimated by scoring the extent that heart rate variation was synchronous across team members, was explored as a predictor of teamwork effectiveness during 20 real planning meetings over a 6-month period. Speech activity and heart rate variability of all four (2 male, 2 female) team members were continuously monitored. Exploratory analyses tested if team member ratings of various aspects of teamwork effectiveness were predicted by SPC scored (1) over whole meetings, (2) during one team member's speech, (3) during periods in which two team members spoke in sequence or (4) over 30-s periods and averaging highest values. SPC during periods of sequential speech negatively predicted team members' ratings of Team productivity, Quality of communication, and Ability to work together. SPC shows potential as an objective, non-invasive means to monitor teamwork effectiveness but this relationship warrants further investigation and replication before use in ergonomics applications. 相似文献
74.
Kristof De Witte Rui C. Marques 《International Transactions in Operational Research》2009,16(2):257-271
Environmental factors add complexity to the comparison between specific activities or entire entities. Decision making units with an inferior performance are tempted to invoke that their organization is "different" from the others in the data set. By reinterpreting and extending the metafrontier literature, we propose an all-embracing concept to fully capture the operational environment. We suggest the "Group Specific Technical Efficiency" as a new measure to assess the overall efficiency of a utility while allowing for environmental differences. A real-world example of drinking water utilities from five different countries illustrates the concept. 相似文献
75.
The production of high performance metal parts requires a well balanced sequence of operations and can usually technologically not be achieved in a single process. This issue leads to complex process chains on the shop floor and the requirement to split single processes into multistage processes in hard-finishing operations. In both cases, the objective for the process planning is to achieve not only a local optimum for the individual processes but rather an overall optimum for the complete sequence. In order to reach the overall optimum, the process planner needs to integrate the effects between the processes into consideration. These effects which are referred to as cross-process interdependencies lead to balanced settings of process parameters and results in a much more effective operation of the sequence. In this paper, a novel approach dealing with the integration of cross-process interdependencies in the hard-finishing process of multistage grinding is introduced. It is based on an a-priori multicriteria dimensioning procedure which allows the integration of cross-process interdependencies and is implemented in software programmed in JAVA. A multistage plunge grinding process for crankshaft journals is used for evaluation of the results predicted by a developed software prototype. 相似文献
76.
Henning Wicht 《电子元器件资讯》2010,(12)
据iSuppli公司,虽然德国作为新增太阳能安装之王获得了光伏(PV)市场的王冠,但欧洲其它国家也在扩大自己的2010年及未来光伏计划.
实际上,欧洲其它可以替代德国成为投资热点的地区大量涌现,意大利和法国的投资回报(ROI)就非常吸引人.iSuppli公司已经看到,大多数德国太阳能投资者涌向这些国家,以拓宽投资范围. 相似文献
77.
78.
Jacob W. Schmidt Anders Bennitz Bj?rn T?ljsten Henning Pedersen 《Canadian Metallurgical Quarterly》2010,14(4):397-405
A durable and very efficient external strengthening system is achieved if steel tendons for posttensioning applications can be replaced with carbon fiber-reinforced polymer (CFRP) tendons, and if reliable anchorage systems are developed. This paper presents a newly developed and simple-to-use, two-piece wedge anchorage for CFRP tendons with an integrated sleeve and a differential angle between barrel and wedge sections. Three longitudinal slits are cut into the one-piece wedge, with one slit open and the other two stopping 1 mm from the inner wedge hole. The integrated sleeve holds the wedge’s sections together during presetting and loading, resulting in a circumferential confined gripping of the CFRP tendon and optimized surface friction area. Therefore, the one-piece wedge differs from conventional wedge systems, where the wedges act separately with adjacent spaces, wedging the separate tendon sleeve in the longitudinal direction. Evaluation of the failure modes during testing was one of the main keys in achieving an increasingly better performance of the anchorage until the final anchorage was developed. The obtained failure modes are therefore described to enlighten the importance of addressing them when testing. The test setup used and measured behavior are described further together with the loading procedure. The anchorage reached the full capacity of the CFRP tendon and was seen to ensure a stable load of fracture. 相似文献
79.
The global distribution of acidifying wet deposition 总被引:2,自引:0,他引:2
The acid-base status of precipitation is a result of a balance between acidifying compounds--mainly oxides of sulfur and nitrogen--and alkaline compounds--mainly ammonia and alkaline material in windblown soil dust. We use current models of the global atmospheric distribution of such compounds to estimate the geographical distribution of pH in precipitation and of the rate of deposition of hydrogen ion or bicarbonate ion. The lowest pH values--mainly due to high concentration of sulfuric acid--occur in eastern parts of North America, Europe, and China. A comparison with observed pH values shows fair agreement in most parts of the world. However, in some areas, e.g. western North America, southwestern Europe, and northern China the estimated pH is too low, indicating that we have underestimated the deposition flux of alkaline material, probably mainly CaCO3. Our neglect of organic acids may have contributed to an overestimate of pH especially in certain tropical areas. To illustrate the potential effects of acidifying deposition on nitrogen saturated terrestrial ecosystems we also calculate the deposition of "potential acidity" that takes into account the microbial transformation of ammonium to nitrate in such ecosystems, resulting in the release of hydrogen ion. Compared to the deposition of acidity, with its maxima over Europe, eastern North America, and southern China, the deposition of potential acidity exhibits an additional maximum in India and Bangladesh and in several other smaller hot spots where the cycling of ammonia is enhanced by a dense cattle population. To the extent that soils in these areas of high potential acidity deposition actually become nitrogen saturated a depletion of base cations and other changes in soil chemistry and biology should be expected. Potential problem areas forfuture soil acidification include several regions with sensitive soils in southern, southeastern, and eastern Asia as well as in central parts of South America. 相似文献
80.
Chris?L.?Barrett Henning?S.?MortveitEmail author Christian?M.?Reidys 《Artificial Life and Robotics》2002,6(4):167-169
We present our work on the special class of dynamical systems referred to as discrete sequential dynamical systems (SDS).
The definition of these systems is motivated by the generic structure of computer simulations. In computer simulations, we
typically find agents or entities with certain properties or states. The entities can retrieve information from other entities,
but usually only from the ones in their own vicinity. Based on these states, they may update their own state. A schedule will
take care of the update order of the entities. One possible interpretation of this is to have each entity as a vertex in a
(dependency) graph where two vertices are connected if the corresponding two entities can communicate. Without loss of generality,
we can associate a binary state to each vertex or entity. Finally, we fix some ordering of the vertices that represents the
update ordering of the entities. The above construction will be put in a strict mathematical context, and leads to the concept
of a sequential dynamical system (SDS).
This work was presented in part at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, January 15–17,
2001 相似文献