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排序方式: 共有816条查询结果,搜索用时 15 毫秒
741.
742.
Hongbo Wang Fumio Kasagami 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2008,38(1):60-67
This paper presents a patient transfer apparatus between bed and stretcher. This apparatus makes it possible for the nurse to move weak, injured, or paralyzed patient from bed to stretcher, or vice versa, alone. Moreover, the suffering, stress, and uneasy feeling of the patient can be alleviated. This paper describes the specification, mechanical design, control system, and motion control of the apparatus. A special devised mechanism is developed, and a new servo system is used in this control system. The control principle and algorithm of the new servo system are proposed, and the motion-control method and safety function of the apparatus are described. The experimental results and evaluation indicated the effectiveness of this system. 相似文献
743.
744.
Macroporous carbon prepared by flash heating of sawdust 总被引:1,自引:0,他引:1
745.
Fumio Nogata 《Strain》2000,36(1):3-8
This paper describes a cell based mechanosensing power and adapting modelling mechanisms found in plants. Biological structures consist of mechanical load carriers, which are strongly optimised in terms of mechanical strength and minimum mass. It is shown that bamboo structures are designed to have uniform stresses at all positions, applying various sizes of bamboo fibre at the optimal locations. As a significant biological design system, a biological sensing power for detecting the strain/stress induced by external loads can be accepted. The mechanosensing system can be regarded as that in which live cells detect the external mechanical strain/stress as biological electric signals generated by the motions of various ions throughout and/or into the channels of the cell membrane. The modelling mechanism is a cell based mechanosensor that depends on the kind of plant. Three types for detecting the mechanical strain/stress (tension sensitive, compression sensitive, and tension and compression sensitive types) are investigated. Changes in electrical signals at the local portion of a plant body due to the mechanical deformation of cell membranes, affect the modelling of a plant's tissue to fit external mechanical environments. 相似文献
746.
Norihiko Yokoi Hiroshi Inaba Makoto Terauchi Adam Z. Stieg Nusrat J. M. Sanghamitra Tomomi Koshiyama Katsuhide Yutani Shuji Kanamaru Fumio Arisaka Tatsuo Hikage Atsuo Suzuki Takashi Yamane James K. Gimzewski Yoshihito Watanabe Susumu Kitagawa Takafumi Ueno 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(17):1873-1879
747.
The Kinect sensor is a powerful tool for applications that require machine vision and voice recognition. The sensor has the capability to detect and track up to two individuals within its field of view and output 20 key 3D “skeleton” joints on these individuals at 30 frames per second. Moreover, the sensor also has a sound-localizing array of microphones that is used to compute the azimuth of any primary sound source within its range. While this skeleton data have good accuracy most of the time, the 20 tracking points exhibit a high level of jitter due to noise and estimation error, and when a subject moves slightly out of the field of view of the sensor for a short period of time, there is no built-in capability to continue the tracking by extrapolating the positions of these points. In addition, the sensor does not take advantage of the sound source angle when the subject being tracked is speaking. In this work, tracking with the sensor is improved by applying an extended Kalman filter. This filter smooths out the jitter, adds the capability to continue tracking for a short period of time when the subject moves out of range of the sensor, and improves the accuracy of the tracking by incorporating the information contained in the sound source angle from the sensor. The efficacy of the filter is demonstrated by applying it to the skeleton head joint, a tracking point near the center of the subject’s head. 相似文献
748.
Omori K Isoyama-Tanaka J Ihara F Yamada Y Nihira T 《Journal of Bioscience and Bioengineering》2005,100(3):323-330
Pseudomonas sp. strain 109 secretes lactonizing lipase (LipL), which catalyzes efficient intramolecular transesterification of omega-hydroxyfatty acid esters to form macrocyclic lactones. Because Escherichia coli was found to be unsuitable as an expression host due to the predominant formation of inactive LipL-inclusion bodies and a lack of proper secretion machinery which is also required for the formation of active LipL, Pseudomonas strains were surveyed as expression hosts. Pseudomonas sp. strain 109, an original LipL producer, showed a 7.1-fold higher level of active LipL when the lipL gene under the control of tac-lacUV5 tandem promoter was introduced together with a limL gene encoding a LipL-specific chaperon. Pseudomonas aeruginosa ADD 1976 containing a T7 RNA polymerase gene in the chromosome and plasmid-borne lipL-limL genes under the control of T7 promoter showed a 13-fold higher level of active LipL. Several combinations in the number of lipL and/or limL genes on the plasmid were investigated, and (lipL)3-limL was found to be most efficient, yielding a 67-fold greater production of active LipL than that obtained by the wild-type Pseudomonas sp. strain 109. 相似文献
749.
Kanatip Kumproa Apinon Nuntiya Qiwu Zhang Junya Kano Fumio Saito 《International Journal of Hydrogen Energy》2014
The objectives of this work, were to produce high-purity hydrogen gas from rice husk by two-step process and to study the effect of nickel hydroxide/nickel acetate/sodium acetate and calcium hydroxide on the concentration of gaseous products. The samples were characterized by X-ray diffraction (XRD) and thermogravimetry-mass spectroscopy (TG/MS). The gaseous products were analyzed by gas chromatography (GC). The results indicated that hydrogen gas was produced from the milled samples by heating at 400–600 °C with the low concentrations of methane, carbon monoxide and carbon dioxide. The highest concentration of hydrogen gas from milled samples with the catalyst, was approximately 95–97 %mol. Furthermore, the milled samples with the carbon dioxide capture agent gave the carbon dioxide concentration, was below 2 %mol. 相似文献
750.