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221.
222.
A dynamic load balancing method is proposed that uses a multistage switching network to solve the problem of load concentration on certain processors for video coding in multiprocessor digital signal processors. (DSPs) This method balances the processing load by distributing the total load among the processor elements having smaller loads. The load distribution is performed by the multistage switching network, which transmits the load quantity information within the network. A scheduling method for a motion picture coding algorithm using multiprocessor DSPs is also proposed. This scheduling method takes full advantage of the multistage switching network functions when distributing the processing load and sorting the processed results. By using computer simulation, multiprocessor DSP performance with the proposed method is shown to be double that of a conventional multiprocessor DSP when an initially unbalanced load is allocated to the processors, as in picture coding for TV conferences  相似文献   
223.
To establish medical use of tissue engineering technology for ligament and tendon injuries, a scaffold was developed which has sufficient ability for cell growth, cell differentiation, and mechanical properties. The scaffold made from chitosan and 0.1 per cent hyaluronic acid has adequate biodegradability and biocompatibility. An animal experiment showed that the scaffold has less toxicity and less inflammation induction. Furthermore, in-vivo animal experiments showed that the mechanical properties of the engineered ligament or tendon had the possibility to stabilize the joint. It was shown that newly developed hybrid-polymer fibre scaffold has feasibility for joint tissue engineering.  相似文献   
224.
Recently, localization methods based on detailed maps constructed using simultaneous localization and mapping have been widely used for mobile robot navigation. However, the cost of building such maps increases rapidly with expansion of the target environment. Here, we consider the problem of localization of a mobile robot based on existing 2D street maps. Although a large amount of research on this topic has been reported, the majority of the previous studies have focused on car-like vehicles that navigate on roadways; thus, the efficacy of such methods for sidewalks is not yet known. In this paper, we propose a novel localization approach that can be applied to sidewalks. Whereas roadways are typically marked, e.g. by white lines, sidewalks are not and, therefore, road boundary detection is not straightforward. Thus, obtaining exact correspondence between sensor data and a street map is complex. Our approach to overcoming this difficulty is to maximize the statistical dependence between the sensor data and the map, and localization is achieved through maximization of a mutual-information-based criterion. Our method employs a computationally efficient estimator of squared-loss mutual information, through which we achieve near real-time performance. The efficacy of our method is evaluated through localization experiments using real-world data-sets  相似文献   
225.
The ability of InTa1− x V x O4 ( x =0, 0.002, 0.005, 0.01) and InTaO4− y N y ( y =0, 0.048, 0.059) powders to photocatalyze the oxidative decomposition of gaseous 2-propanol (IPA) when irradiated by the same number of visible or ultraviolet photons was confirmed. The first-principle calculations of InTa0.875V0.125O8 indicated that the V 3d introduced state was discretely situated below the conduction band, which was composed mainly of Ta 5d. Similar calculations of InTaO3.5N0.5 indicated that the N 2p state was above the valence band, which was composed of O2p. These discrete narrow bands were responsible for the visible light sensitivity in the V- or N-doped InTaO4 compounds.  相似文献   
226.
P.K. Song  Y. Irie 《Thin solid films》2006,496(1):121-125
TiO2 films with thicknesses of 400-460 nm were deposited on the unheated non-alkali glass by radio frequency (rf) reactive magnetron sputtering using a Ti metal target. Depositions were carried out using a 3-in. 1000 G magnetron cathode with various rf substrate bias voltages (Vsb, dc component of self bias) of 10-80 V under total gas pressure of 1.0 or 3.0 Pa. The oxygen flow ratio [O2/(O2 + Ar)] and rf sputtering power were kept constant at 60% and 200 W, respectively. Photocatalytic activity on photoinduced oxidative decomposition of acetaldehyde (CH3CHO) of the TiO2 films showed a clear tendency to decrease with the increase in the Vsb during the deposition. Most of the films consisted of the mixture of anatase and rutile polycrystalline portions. It was confirmed that the rutile phase content increased and anatase phase content decreased markedly with increasing Vsb, where the crystallinity of anatase phase was much higher than that of rutile phase.  相似文献   
227.
Adhesion and sliding of wet snow on a superhydrophobic surface with hydrophilic channel were investigated. Two different alignment (two dimensional and three dimensional) of the hydrophilic channels in a superhydrophobic surface were prepared and compared with merely a superhydrophobic surface and a hydrophilic surface. Both alignment samples exhibited intermediate level of wet snow adhesion between merely a superhydrophobic surface and a hydrophilic surface. Although the three dimensional sample also showed intermediate level for the wet snow sliding behavior, the two dimensional sample exhibits poorer snow sliding behavior than a superhydrophobic surface. Based on the experiments using a water-hollow glass beads composite, water movement to hydrophilic parts from wet snow occurs on both samples. It is deduced that the poor sliding behavior on the two dimensional sample was due to the increase of viscosity of wet snow on superhydrophobic parts as a result of the water movement to hydrophilic parts.  相似文献   
228.
Tsujioka T  Irie M 《Applied optics》1998,37(20):4419-4424
The fluorescence- and transmittance-detection readout methods of a near-field photochromic optical memory by a scanning-probe technique were studied theoretically. Shot noise, as the principal noise, was taken into account in an analysis of the signal-to-noise ratio (SNR). Under most conditions, fluorescence-detection readout yielded a better SNR than did transmittance-detection readout. For a transmittance change of 0.9-1.0 as a result of recording, a readout light power of approximately 100 nW, and a system bandwidth of 1 MHz, only the fluorescence-detection readout method, under the condition that the fluorescent layer of the medium have a fluorescence quantum yield greater than 0.4, can produce a sufficiently large SNR.  相似文献   
229.
The Japan Proton Accelerator Research Complex (J-PARC) has been under construction in Tokai-mura, Ibaraki, Japan. Three independent charge stripper devices are set up at the injection line of the 3 GeV Rapid Cycling Synchrotron (RCS). The H beam accelerated by a 181 MeV Linac is charge-exchanged to a H+ beam by the first stripper foil, and then injected into the RCS. The H0 and H fractions of the beam, which are not stripped by the first stripper foil, are converted into a H+ beam by the second and the third stripper foils.We have designed the charge exchange devices by adopting the transfer-rod system for moving the foils in a vacuum. We have fabricated a new type of transfer-rod, which can move over a distance of 1500 mm.We have also developed a new telescope system to observe possible wrinkles and pinholes of the foil. The system withstands more than 1 MGy of radiation dose and has a resolution of 250 μm at a distance of 10 m from an object.  相似文献   
230.
用微波等离子体化学气相沉积方法合成高品质同质外延金刚石膜,并且用扫描电镜和阴极荧光分析法评价。为了得到高薄膜生长速率,把甲烷浓度设定在4%。薄膜上的生长丘的数量和大小依赖于生长条件。在本工作的样品中,未发现任何非外延晶粒。室温下的阴极荧光分光结果表明这种金刚石薄膜具有与自由励起子相关的谱峰。氢终端的膜表面制作的铝电极显示了P型整流特性。击穿电压高于380V。实验结果表明,阴极荧光分析法观测到的缺陷和电性能密切相关,并且可以在有室温边发射的金刚石表面上制作具有高击穿电压的整流电极。  相似文献   
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