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111.
In this paper, we propose a novel noncontact pulse wave monitoring method that is robust to fluctuations in illumination through use of two-band infrared video signals. Because the proposed method uses infrared light for illumination, the method can be used to detect a pulse wave on a human face without visible lighting. The corresponding two-band pixel values in the video signals can be separated into hemoglobin and shading components by application of a separation matrix in logarithmic space for the two pixel values. Because the shading component has been separated, the extracted hemoglobin component is then robust to fluctuations in the illumination. The pixel values in the region of interest were spatially averaged over all the pixels of each frame. These averaged values were then used to form the raw trace signal. Finally, the pulse wave and the corresponding pulse rate were obtained from the raw trace signal through several signal processing stages, including detrending, use of an adaptive bandpass filter, and peak detection. We evaluated the absolute error rate for the pulse rate between the estimated value and the ground truth obtained using an electrocardiogram. In the experiments, we found that the performance of the proposed method was greatly improved compared with that of conventional methods using single-band infrared video.  相似文献   
112.
Abstract— A new front‐projection system for large screens by diffusing only projected light to wards the viewing‐angle range and reflecting ambient light towards the other angle ranges is proposed. With this system, a high‐quality and large‐sized front‐projection display with a high contrast ratio even in a bright room has been realized.  相似文献   
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We performed a numerical analysis for simulating granular media structures containing non‐spherical elements and the liquid trickle flow characteristics of such structures. Fully‐Lagrangian numerical simulation methods can track all motion information for solid or liquid elements at each point in time. We introduced suitable compressibility to moving particle semi‐implicit (MPS) and performed individual packing behavior calculations for non‐spherical elements, based on discrete element method (DEM) with expanded functions. Rigid bodies‐DEM is a method using a DEM contact force model that is expanded to handle the motion of freely shaped solids. It expresses complex shapes to enable low calculation costs and intuitive mounting. We used the boundary for the granular media configured with non‐spherical elements to implement a trickle flow simulation based on weakly compressible‐MPS. Even for elements of equal volume, different shapes changed the liquid passage velocity and hold‐up amount. The mean downflow velocity of the liquid phase was not always dependent on the void fraction. For the plane of projection, we obtained a good correlation with the mean downflow velocity in each packed structure, and successfully performed arrangements according to the new liquid‐passage shape coefficient. © 2016 American Institute of Chemical Engineers AIChE J, 63: 2257–2271, 2017  相似文献   
115.
Organometal halide perovskites have attracted widespread attention as the most favorable prospective material for photovoltaic technology because of their high photoinduced charge separation and carrier transport performance. However, the microstructural aspects within the organometal halide perovskite are still unknown, even though it belongs to a crystal system. Here direct observation of the microstructure of the thin film organometal halide perovskite using transmission electron microscopy is reported. Unlike previous reports claiming each phase of the organometal halide perovskite solely exists at a given temperature range, it is identified that the tetragonal and cubic phases coexist at room temperature, and it is confirmed that superlattices composed of a mixture of tetragonal and cubic phases are self‐organized without a compositional change. The organometal halide perovskite self‐adjusts the configuration of phases and automatically organizes a buffer layer at boundaries by introducing a superlattice. This report shows the fundamental crystallographic information for the organometal halide perovskite and demonstrates new possibilities as promising materials for various applications.  相似文献   
116.
Fe-containing MWW zeolite catalysts in the absence (Fe-MWW) or presence of Al atoms (Fe,Al-MWW) were directly prepared by the hydrothermal synthesis approach. The nature of Fe species was systematically analyzed by UV–vis, in-situ NO adsorption FTIR spectroscopy, and H2-TPR technology. The presence of Al atoms in the synthesis gel seriously affected the chemical composition, textural properties, and the states of Fe species, hence made the catalytic activity in hydroxylation of benzene with H2O2 worse than the one without Al. Moreover, we found that the states of Fe species could be adjusted by changing the calcination temperature. The catalytic activity of Fe-MWW was improved by increasing the calcination temperature, while that of Fe,Al-MWW was weakened due to the degeneration of texture properties and the transformation of Fe species. Fe-MWW zeolite calcined at 750 °C exhibited the highest 8.3% yield and 94% selectivity to phenol in direct hydroxylation of benzene with H2O2.  相似文献   
117.
Particle flowability can be improved by admixing with particles smaller than the main particles. However, the mechanism by which this technique improves flowability is not yet fully understood. In this study, we focused on vibrating discharge particle flowability as one type of flowability and investigated the influence of the main particle roughness created by the adhesion of the admixed particles on improving the flowability. The diameters of the main and admixed particles (MPs and APs) were 41.4 or 60.8?μm and 8 or 104?nm, respectively. The main and admixed particles were mixed in various mass ratios, and the discharge particle flow rates of the mixed particles were measured. Scanning electron microscopy images were acquired from two different angles to determine the three-dimensional surface roughness using image analysis software. We then calculated the coating structure parameters from the obtained three-dimensional surface roughness. The observed trends for improving the vibrating discharge particle flowability were found to differ from those reported for compression particle flowability. Furthermore, the main particle roughness conditions that led to the greatest improvement involved the presence of several admixed particle agglomerations between the main particles.  相似文献   
118.
In an effort to create a truly flexible and wearable display having a flexible battery as well as a flexible organic light‐emitting diode panel and a flexible printed circuit, a flexible lithium‐ion battery has been developed, and a prototype wrist‐wearable or arm‐wearable display has been fabricated. Owing to improvements in the internal structure and exterior of the lithium‐ion battery, no remarkable changes in charge and discharge curves and the internal state of the electrodes were observed even after conducting a 10,000‐cycle bending test. Therefore, this flexible lithium‐ion battery prototype demonstrated remarkable bending resistance. Thus, we succeeded in fabricating a truly flexible and wearable display comprised of a flexible organic light‐emitting diode panel, a flexible printed circuit, and a flexible battery.  相似文献   
119.
Phospholipids (PL) containing n‐3 polyunsaturated fatty acids (PUFA) have beneficial effects of maintaining and promoting health compared with triacylglycerols (TAG) containing n‐3 PUFA or general PL. This study evaluated the effects of dietary PL containing n‐3 PUFA and elucidated the effects of the glycerophosphate structure and n‐3 PUFA on fatty acid (FA) metabolism in rats. Rats were fed a basal diet containing soybean oil alone, TAG containing n‐3 PUFA (1.8 %), soybean PL (2.7 %), PL containing n‐3 PUFA (2.7 %), or TAG containing n‐3 PUFA (1.8 %) + soybean PL (2.7 %). The present n‐3 PUFA‐supplemented diets had similar FA compositions, and the PL diets had similar PL compositions. TAG containing n‐3 PUFA reduced serum TAG contents, but did not affect serum cholesterol contents compared with soybean oil alone. PL diets containing n‐3 PUFA and the combination of TAG containing n‐3 PUFA and soybean PL resulted in decreased serum and liver TAG contents compared with the diet containing soybean oil alone, reflecting enhanced liver FA β‐oxidation. The results of this study show that TAG containing n‐3 PUFA with added soybean PL affects serum and liver TAG and cholesterol contents to a similar degree as PL containing n‐3 PUFA. TAG containing n‐3 PUFA and soybean PL are widely used as functional food ingredients and pharmaceutical constituents and are inexpensive compared with PL containing n‐3 PUFA. Therefore, the combination of TAG containing n‐3 PUFA and soybean PL has potential as a useful and inexpensive component of functional foods.  相似文献   
120.
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