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31.
Pradhan S. Tajima K. Tanaka K. 《Knowledge and Data Engineering, IEEE Transactions on》2001,13(5):824-838
While a query result in a traditional database is a subset of the database, in a video database, it is a set of subintervals extracted from the raw video sequence. It is very hard, if not impossible, to predetermine all the queries that will be issued in the future, and all the subintervals that will become necessary to answer them. As a result, conventional query frameworks are not applicable to video databases. We propose a new video query model that computes query results by dynamically synthesizing needed subintervals from fragmentary indexed intervals in the database. We introduce new interval operations required for that computation. We also propose methods to compute relative relevance of synthesized intervals to a given query. A query result is a list of synthesized intervals sorted in the order of their degree of relevance 相似文献
32.
Keisuke Ichida Kiyotaka Izumi Keigo Watanabe Nobuhiro Uchida 《Artificial Life and Robotics》2008,12(1-2):258-263
In general, manipulators used for industry and in academic laboratories have actuators to drive each joint. On the other hand,
underactuated manipulators handled by our research have some passive or free joints without actuators and brakes. We recently
developed a switching method of fuzzy energy regions to control such manipulators. In such a method, it is necessary to design
parameters related to energy regions and the gains of some partly stable controllers based on the computed torque method.
Here, the switching method is applied for a three-link underactuated manipulator. We optimize such design parameters related
to fuzzy energy regions by a genetic algorithm. The effectiveness of the present method is illustrated with some simulations.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
33.
Tajima K Orisaka M Yata H Goto K Hosokawa K Kotsuji F 《Microscopy research and technique》2006,69(6):450-458
We developed a culture system in which two types of ovarian follicular cells were allowed to attach to opposite sides of a collagen membrane. Using this in vitro cell culture system, we studied the effects of granulosa- and theca-cell interaction on the morphology, structure, and function of bovine ovarian follicular cells. In the first part of the study, we explored how the interaction between theca and granulosa cells affects the morphology and structure of the cells. This study was done using follicular cells collected from bovine ovarian follicles at the early developmental stage. Granulosa cells cultured alone were flattened, and formed a monolayer sheet. By contrast, granulosa cells cultured with theca cells were convex, and formed multilayer sheets. Theca cells cultured alone were thin, flat, and spindle-shaped. Theca cells cultured with granulosa cells were also spindle-shaped; however, they appeared convex and more densely packed when compared with theca cells cultured alone. In the second part of the study, the possible role of the cellular interaction in the control of differentiation and growth of granulosa and theca cells was investigated. When follicular cells were isolated from the early stage of follicular development, theca cells reduced progesterone and inhibin production by granulosa cells and augmented the growth of granulosa cells. When the cells were isolated from the late stage of follicular development, by contrast, theca cells augmented hormonal production by granulosa cells, and did not affect the growth of granulosa cells. The growth and androstenedione production by theca cells were increased by the presence of granulosa cells, irrespective of the origin of follicular cells. These results demonstrated that communication between two types of follicular cells results in reciprocal modulation of their morphology, structure, growth, and function. Cellular interactions seem to be one of the major factors controlling the differentiation and growth of the follicular cells during the follicular maturation process. In contrast to granulosa and theca cells cultured alone, cells in the coculture seemed to possess morphological and functional characteristics more similar to those of cells in the growing follicular wall in vivo. Thus, we speculate that the interaction between these two types of follicular cells is essential for the maintenance of original structure and function of the bovine follicular wall. 相似文献
34.
I Tanabe K Kusaba Z Nagasawa Y Tajima J Tadano N Fujisawa O Kato H Yamada 《Canadian Metallurgical Quarterly》1993,67(8):718-723
A recent nationwide increase in beta-lactams-resistant Streptococcus pneumoniae has attracted a great deal of attention. We studied the drug sensitivity of S. pneumoniae isolated from various clinical specimens in Saga Medical School Hospital between April 1988 and December 1991. To determine the drug sensitivity of the strains, we used a micro-dilution method and determined the MIC. Drug resistance was evaluated using MIC of ampicillin (ABPC) as a reference MIC, and the results were roughly classified into the following three groups: sensitive (< or = 0.1 microgram/ml), moderately resistant (0.2-3.13 micrograms/ml) and highly resistant (> or = 6.25 micrograms/ml). The isolation frequency was calculated on the basis of one strain from one patient. No strain of S. pneumoniae with high resistance against ABPC was found in 1988 (94 strains of S. pneumoniae were isolated) and 1990 (115 strains isolated), but one such strain (0.8%) was found among 129 strains isolated in 1989, and 2 such strains (2.4%) among 84 strains isolated in 1991. Moderately resistant strains were isolated at the frequencies of 12.8%, 15.5%, 22.6%, and 21.4% respectively, in 1988, 1989, 1990, and 1991. A sum of the frequencies of "moderately resistant" and "highly resistant" (2.4%) strains was 23.8% in 1991. The frequency of resistant strains is increasing and the intensity of resistance is also being elevated. 相似文献
35.
Peculiar dendritic deposits of mercury were obtained galvanostatically from the mercurous nitratemethanol-water system at –50° C. These deposits could not be maintained at a constant shape because, when the current was interrupted, they transformed and shrank immediately to a spherical shape with hydrogen evolution. It seems that when the electrical potential was removed, the mercury deposits liquefied and the hydrogen stored in them was released during the period of shrinking. 相似文献
36.
T. Sasaki N. Yoneyama A. Suzuki I. Ito N. Kobayashi Y. Ikemoto H. Kimura N. Hanasaki H. Tajima 《Journal of Low Temperature Physics》2006,142(3-4):377-382
The electronic phase separation on macroscopic scale is studied in the organic Mott system κ-(BEDT-TTF)2Cu[N(CN)2]Br by means of scanning microregion infrared spectroscopy using the synchrotron radiation. The phase separation appears in
the vicinity of the Mott boundary in the single crystals of which the band width is controlled by partly substituting the
BEDT-TTF molecule with the deuterated one. The transport properties under the phase separation are considered to be influenced
by the percolation process of the domains. 相似文献
37.
Etching characteristics of high-k dielectric materials (HfO2) and metal electrode materials (Pt, TaN) have been studied in high-density chlorine-containing plasmas at pressures around 10 mTorr. The etching of HfO2 was performed in BCl3 without rf biasing, giving an etch rate of about 5 nm/min with a high selectivity of >10 over Si and SiO2. The etching of Pt and TaN was performed in Ar/O2 with high rf biasing and in Ar/Cl2 with low rf biasing, respectively, giving a Pt etch rate of about several tens nm/min and a TaN etch rate of about 200 nm/min with a high selectivity of >8 over HfO2 and SiO2. The etched profiles were outwardly tapered for Pt, owing to the redeposition of etch or sputter products on feature sidewalls, while the TaN profiles were almost anisotropic, probably owing to the ion-enhanced etching that occurred. 相似文献
38.
We propose a quantum bit-commitment scheme based on quantum one-way permutations with the unconditionally binding and computationally
concealing property. Our scheme reduces exponentially the number of bits which the receiver needs to store until, the opening
phase compared with the classical counterpart.
Keisuke Tanaka, Ph.D.: He is Assistant Professor of Department of Mathematical and Computing Sciences at Tokyo Institute of Technology. He received
his B.S. from Yamanashi University in 1992 and his M.S. and Ph.D. from Japan Advanced Institute of Science and Technology
in 1994 and 1997, respectively. For each degree, he majored in computer science. Before joining Tokyo Institute of Technology,
he was Research Engineer at NTT Information Sharing Platform Laboratories. His research interests are cryptography, quantum
computation, circuit complexity, and the design and analysis of algorithms. 相似文献
39.