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991.
Color segmentation for text extraction 总被引:1,自引:1,他引:0
Hiroyuki?HaseEmail author Masaaki?Yoneda Shogo?Tokai Jien?Kato Ching?Y.?Suen 《International Journal on Document Analysis and Recognition》2003,6(4):271-284
The capability of extracting and recognizing characters printed in color documents will widen immensely the applications of OCR systems. This paper describes a new method of color segmentation to extract character areas from a color document. At first glance, the characters seem to be printed in a single color, but actual measurements reveal that the color image has a distribution of components. Compared with clustering algorithms, our method prevents oversegmentation and fusion with the background while maintaining real-time usability. It extracts the representative colors based on a histogram analysis of the color space. Our method also contains a selective local color averaging technique that removes the problem of mesh noise on high-resolution color images.Received: 25 July 2003, Revised: 10 August 2003, Published online: 6 February 2004Correspondence to: Hiroyuki Hase. Current address: 3-9-1 Bunkyo, Fukui-shi 910-8507, Japan 相似文献
992.
Bulk metallic glasses--formed by supercooling the liquid state of certain metallic alloys--have potentially superior mechanical properties to crystalline materials. Here, we report a Co(43)Fe(20)Ta(5.5)B(31.5) glassy alloy exhibiting ultrahigh fracture strength of 5,185 MPa, high Young's modulus of 268 GPa, high specific strength of 6.0 x 10(5) Nm kg(-1) and high specific Young's modulus of 31 x 10(6) Nm kg(-1). The strength, specific strength and specific Young's modulus are higher than previous values reported for any bulk crystalline or glassy alloys. Excellent formability is manifested by large tensile elongation of 1,400% and large reduction ratio in thickness above 90% in the supercooled liquid region. The ultrahigh-strength alloy also exhibited soft magnetic properties with extremely high permeability of 550,000. This alloy is promising as a new ultrahigh-strength material with good deformability and soft magnetic properties. 相似文献
993.
A five-year research and development project on an integrated nuclear data utilisation system was initiated in 2002, for developing innovative nuclear energy systems such as accelerator-driven systems. The integrated nuclear data utilisation system will be constructed as a modular code system, which consists of two sub-systems: the nuclear data search and plotting sub-system, and the nuclear data processing and utilisation sub-system. The system will be operated with a graphical user interface in order to enable easy utilisation through the Internet by both nuclear design engineers and nuclear data evaluators. This paper presents an overview of the integrated nuclear data utilisation system, describes the development of a prototype system to examine the operability of the user interface and discusses specifications of the two sub-systems. 相似文献
994.
Na KS Nagayasu K Kuroda A Takiguchi N Ikeda T Ohtake H Kato J 《Journal of Bioscience and Bioengineering》2005,99(4):408-414
Rhodococcus opacus B-4 and B-9 are tolerant to various organic solvents including benzene, toluene, ethylbenzene, xylenes and styrene, and are suitable bacterial hosts for the production of chemical products from hydrophobic substrates. A 4.4-kb endogenous plasmid (pKNR 01) was isolated from R. opacus B-4 and sequenced completely. Plasmid pKNR 01 encodes proteins that share similarity to replication proteins from the enteric bacterial and actinomycete theta-replication plasmids. A 7.4-kb chimeric plasmid, designated pKNR 01.1, was constructed by fusing XhoI-digested pKNR 01 and Escherichia coli vector pSTV 28. Plasmid pKNR 01.1 had the ability to replicate in B-4 and B-9. A protocol for transformation of B-9 by electroporation was optimized employing pKNR 01.1. Frequencies of 4.1 x 10(5) transformants per mug of plasmid DNA were obtained for B-9 cells, whereas B-4 harboring naturally occurring pKNR 01 was transformed at lower frequencies (approximately 1 x 10(4) transformants per mug of plasmid DNA). Deletion analysis of pKNR 01.1 showed that the 1.9-kb SphI-XhoI region containing the repA and rep B genes and the 0.6-kb region upstream of repA was essential for plasmid maintenance in R. opacus strains. 相似文献
995.
Ultrafast asynchronous all-optical signal processing is experimentally demonstrated. It is based on the intensity-dependent, self-frequency shift of a gigahertz Raman soliton. We demonstrate error-free, asynchronous, all-optical, bit-by-bit, self-signal recognition and demultiplexing from contended optical packets without use of an optical buffer, control pulse, or bit-phase synchronization. Fourfold, contended, 9.95-Gbit/s optical packets are transmitted through a conventional repeater span of 80 km and simultaneously demultiplexed to multiwavelength 9.95-Gbit/s optical packets with 0.5-dB processing sensitivity. Furthermore, we successfully accomplish demultiplexing from overlapping signals in contended optical packets with better than 3-dB recognition sensitivity. We confirm the capability of realizing a 3x cascade operation from bit-error-rate measurements. 相似文献
996.
A chemiluminescence-based high-performance liquid chromatographic method was developed for the analysis of the addition products
of α-tocopherol with phosphatidylcholine-peroxyl radicals (TOO-PC). The TOO-PC eluted from a reversed-phase column was reacted
with a chemiluminescent reagent consisting of a Cypridina luciferin analog and a lipid-soluble iron chelate in acidic methanol at 50°C, and the generated chemiluminescence was monitored.
The detection limit for TOO-PC by this method was about 1 pmol. This method was applied to the detection of TOO-PC in the
peroxidized membranes prepared from rabbit erythrocyte ghosts. When the erythrocyte ghosts were peroxidized by the addition
of a water-soluble free radical initiator, a peak corresponding to TOO-PC was detected on the chromatogram with chemiluminescent
detection. The amount of TOO-PC in the erythrocyte membranes increased with the depletion of endogenous α-tocopherol. The
results indicate that this method proved useful for the detection of the TOO-PC formed by the peroxyl-radical scavenging reactions
of α-tocopherol in biological systems. 相似文献
997.
Takeyoshi Kato Tetsuhisa Iida Kai Wu Yasuo Suzuoki 《Electrical Engineering in Japan》2003,143(2):30-37
This paper discusses a conformation of a micro co‐generation system (µCGS) for residential use. The evaluation is based on the hot‐water demand observed in three families who live in the same apartment house. Assuming DSS operation of µCGS, we evaluated the required capacity of PEFC, hot‐water tank, and backup boiler to meet a series of daily hot‐water demand observed in three houses. The results are: (1) µCGS with 2‐kW PEFC and 350‐L hot‐water tank are required in family B when µCGS is not equipped with the backup boiler, (2) the additional 5 kW of the backup boiler reduces the required capacity of the hot‐water tank by 50 L, (3) the evaluation based on hourly averaged hot‐water demand patterns would underestimate the required capacity of the hot‐water tank, (4) the required capacity of the hot‐water tank could be reduced by the leveling effect of the hot‐water demand pattern along three families. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 143(2): 30–37, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10080 相似文献
998.
999.
Yoshimi M. Takahashi M. Wada T. Kato K. Kambayashi S. Kemmochi M. Natori K. 《Electron Devices, IEEE Transactions on》1990,37(9):2015-2021
The drain breakdown phenomenon in ultra-thin-film (silicon-on-insulator) SOI MOSFETs has been studied. Two-dimensional simulation revealed that the thinning of the SOI film brings about an increase in the drain electric field due to the two-dimensional effect, causing a significant lowering in the drain breakdown voltage, as has been commonly seen in ultra-thin-film SOI MOSFETs. The simulation also showed that the lowered drain breakdown voltage recovered almost to its original value when the drain SOI thickness was restored, suggesting that the drain structure, rather than the source, plays a major role in determining the drain breakdown voltage. Experiments using an asymmetric device structure supported this hypothesis, showing that the breakdown voltage was mostly dependent on the drain structure, the initial potential barrier height at the source-SOI-body junction being only a minor factor. Transient simulation was also carried out to investigate the detailed breakdown process, showing that holes accumulate near the source-SOI-body junction at a high drain bias, eventually forward-biasing the junction. These results indicate that a careful drain design and/or proper choice of the SOI thickness as well as the supply voltage are quite important for realizing high performance of ultra-thin-film SOI MOSFETs 相似文献
1000.
Summary Tension tests on 36 specimens of steel plates produced in Japan are carried out according to the testing method proposed by
RILEM TC 83. The stress-strain curves obtained from the tests are mathematically expressed by determining the material constants
included in a modified Menegotto-Pinto model. These results give standardized stress-strain relations with respect to SS41
and SM50A steels generally used in Japan as structural steels for building structures. These kinds of data are expected to
be accumulated by many countries and should be then compared internationally to establish a more reasonable stress-strain
relationship usable for structural analyses. 相似文献