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81.
We propose a design method of phase-analysis algorithms based on two-dimensional grating phase shifting for Talbot interferometry, Talbot-Lau imaging, or the Ronchi test. These algorithms are designed to separate the two orthogonal shearing wavefronts and eliminate error effects of unwanted diffraction orders, simultaneously. Taking the effect of multidiffraction into account, moving the two-dimensional grating along a certain pass leads to a series of phase-shifted interfrograms, from which two orthogonal shearing wavefronts are derived, for the tested wavefront to be retrieved. The designing process is demonstrated, and the residual errors are analyzed via simulation works and experimental comparison.  相似文献   
82.
In the real world, robots should be able to recognize the environment in order to be of help to humans. A video camera and a laser range finder are devices that can help robots recognize the environment. However, these devices cannot obtain tactile information from environments. Future human‐assisting robots should have the ability to recognize haptic signals, and a disturbance observer can possibly be used to provide the robot with this ability. In this study, a disturbance observer is employed in a mobile robot to functionalize the tactile sensation. This paper proposes a method that involves the use of the haptograph and modal decomposition for the haptic recognition of road environments. The haptograph presents a graphic view of the tactile information. It is possible to classify road conditions intuitively. The robot controller is designed by considering the decoupled modal coordinate system, which consists of translational and rotational modes. Modal decomposition is performed by using a quarry matrix. Once the robot is provided with the ability to recognize tactile sensations, its usefulness to humans will increase. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 177(2): 49–57, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21169  相似文献   
83.
Future robots and mechatronic systems will be required to physically support human activities. In order to reach the stage of real human-friendly physical support, they should acquire many functions such as the recognition of the real world based on complicated human actions, the transmission of the ambient information in harmony with human sensation, and so on. Since haptic sensation, as well as visual information and auditory sensation are so important for human activities, haptic motion control is one of the most important issues for the purpose. This paper now presents some haptic motion control techniques as the fundamental technology for the realization of future physical human support. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
84.
In cases of essential fatty acid deficiency, 5,8,11-eicosatrienoic acid (Mead acid, 20:3n-9) is synthesized from oleic acid as a 20-carbon analog of arachidonic acid. It was reported that 20:3n-9 levels were markedly higher in human fetal cartilage than in the muscle, liver and spleen. We, therefore, hypothesized that 20:3n-9 decreased osteoblastic activity. Goldfish scales were incubated either with 20:3n-9 or with oleic acid at 15 °C for 6 and 18 h. Both osteoblastic and osteoclastic activities in the scale were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase, respectively. MC3T3-E1 cells (an osteoblast cell line derived from the mouse) were incubated with 20:3n-9 or oleic acid at 37 °C for 6 and 18 h. ALP activity in cell lysate was measured. In the case of experiments with scales, 20:3n-9 (1–100 μM) significantly suppressed osteoblastic activity after 6 and 18 h of incubation, whereas oleic acid did not change this activity. Osteoclastic activity was not affected either by 20:3n-9 or by oleic acid. In the case with the cell line, osteoblastic activity was again significantly decreased with 20:3n-9 (10–30 μM) after 6-h incubation but not after 18 h incubation. The presence of 20:3n-9 in fetal cartilage may be important for the prevention of calcification in the cartilage. 20:3n-9 could be applied to some clinical situations where bone formation should be inhibited.  相似文献   
85.
86.
The development and operation of an on-line digital computer for the LD basic oxygen steelmaking shop of Nippon Kokan’s Kawasaki works are described. The mathematical models—evolved for the computer on the basis of statistical analysis of operating data—and the rationale in their development are given in detail. Standard deviation results from six months of computer-controlled operation are reported, and an outline of the entire control process is included.  相似文献   
87.
The decomposition temperature of CeN, U0.5Ce0.5N and U0.75Ce0.25N has been measured as a function of nitrogen pressure. The results are log pN2 [CeN] = 18.2 ? 5.04 × 104T, log pN2 [U0.5Ce0.5N] = 15.0 ? 4.45 × 104T, log pN2 [U0.75Ce0.25N] = 13.6 ? 4.15 × 104T, where pN2 is in atm and T in K. Thermodynamic analysis based on the reaction, in which the solid solution, U1?xCexN, decomposes into U1?xCex(1) and 12 N2(g), results in a very simple relation: logpN2[U0.75Ce0.25N] = (1 ? x) logpN2 [UN] +xlogpN2 [CeN], where the assumption that the interaction parameters for U1?xCexN and U1?xCex(1) have the same value was made. The influence of solubility of nitrogen in U1?xCex (1) has been also taken into consideration. The present experimental data are in good agreement with the equation derived from the present thermodynamic analysis.  相似文献   
88.
89.
High quality gate insulator film formation on 4H-SiC substrate is demonstrated. The insulator films were formed by the PECVD and radical oxynitridation using microwave-excited high-density plasma with NO gas at low temperature. The oxide fixed charge and the interface trap density can be dramatically reduced by NO gas radical oxynitridation after the oxide film formed by the PECVD compared with by direct oxynitridation on 4H-SiC. SIMS profiles show carbon profile in these fabricated gate insulator films. It is confirmed that the electrical property is improved as the amount of remaining carbon in the insulator film decreases.  相似文献   
90.
Analysis of the optical intrinsic signal of an exposed cortex has been applied to measurement of functional brain activation. It is important for accurate measurement of concentration changes in oxygenated hemoglobin and deoxygenated hemoglobin to consider the wavelength dependence of the mean optical path lengths for the reflectance of cortical tissue. A method is proposed to experimentally estimate the wavelength dependence of the mean optical path length in cortical tissue from the multispectral reflectance of the exposed cortex without any additional instruments. The trend in the wavelength dependence of the mean optical path length estimated by the proposed method agrees with that estimated by the model-based prediction, whereas the magnitude of the wavelength dependence predicted by the proposed method is greater than that of the model-based prediction. The experimentally predicted mean optical path length minimizes the difference in the measured changes in the concentrations of the oxygenated hemoglobin and deoxygenated hemoglobin calculated from different wavelength pairs.  相似文献   
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