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991.
Multimedia Tools and Applications - In this paper, we propose a human-centered image classification via a neural network considering visual and biological features. The proposed method has two...  相似文献   
992.
This paper presents an appearance-based method for estimating head direction that automatically adapts to individual scenes. Appearance-based estimation methods usually require a ground-truth dataset taken from a scene that is similar to test video sequences. However, it is almost impossible to acquire many manually labeled head images for each scene. We introduce an approach that automatically aggregates labeled head images by inferring head direction labels from walking direction. Furthermore, in order to deal with large variations that occur in head appearance even within the same scene, we introduce an approach that segments a scene into multiple regions according to the similarity of head appearances. Experimental results demonstrate that our proposed method achieved higher accuracy in head direction estimation than conventional approaches that use a scene-independent generic dataset.  相似文献   
993.
994.
This study considers the subjective evaluation of ride quality during ambulance transportation using an actively-controlled stretcher (ACS). The ride quality of a conventional stretcher and an assistant driver's seat is also compared. Braking during ambulance transportation generates negative foot-to-head acceleration in patients and causes blood pressure to rise in the patient's head. The ACS absorbs the foot-to-head acceleration by changing the angle of the stretcher, thus reducing the blood pressure variation. However, the ride quality of the ACS should be investigated further because the movement of the ACS may cause motion sickness and nausea. Experiments of ambulance transportation, including rapid acceleration and deceleration, are performed to evaluate the effect of differences in posture of the transported subject on the ride quality; the semantic differential method and factor analysis are used in the investigations. Subjects are transported using a conventional stretcher with head forward, a conventional stretcher with head backward, the ACS, and an assistant driver's seat for comparison with transportation using a stretcher. Experimental results show that the ACS gives the most comfortable transportation when using a stretcher. Moreover, the reduction of the negative foot-to-head acceleration at frequencies below 0.2 Hz and the small variation of the foot-to-head acceleration result in more comfortable transportation. Conventional transportation with the head forward causes the worst transportation, although the characteristics of the vibration of the conventional stretcher seem to be superior to that of the ACS.  相似文献   
995.
We have developed a single-shot intensity-measurement system using a silicon positive-intrinsic-negative (PIN) photodiode for x-ray pulses from an x-ray free electron laser. A wide dynamic range (10(3)-10(11) photons/pulse) and long distance signal transmission (>100 m) were required for this measurement system. For this purpose, we developed charge-sensitive and shaping amplifiers, which can process charge pulses with a wide dynamic range and variable durations (ns-μs) and charge levels (pC-μC). Output signals from the amplifiers were transmitted to a data acquisition system through a long cable in the form of a differential signal. The x-ray pulse intensities were calculated from the peak values of the signals by a waveform fitting procedure. This system can measure 10(3)-10(9) photons/pulse of ~10 keV x-rays by direct irradiation of a silicon PIN photodiode, and from 10(7)-10(11) photons/pulse by detecting the x-rays scattered by a diamond film using the silicon PIN photodiode. This system gives a relative accuracy of ~10(-3) with a proper gain setting of the amplifiers for each measurement. Using this system, we succeeded in detecting weak light at the developmental phase of the light source, as well as intense light during lasing of the x-ray free electron laser.  相似文献   
996.
This article addresses the permutation flow-shop scheduling problem with total flow time minimization criterion. The problem is proved to be NP-hard; thus, the development of heuristic methods that provide high-quality solutions with computational efficiency are the motivating aspects for the development of this research. In this article, a new simple constructive heuristic method has been proposed to solve the problem. Initially, an extensive literature review with key methods was performed for analysis, comparison, and evaluation. Then, a new simple heuristic method has been proposed and evaluated by means of extensive computational experiments. The results showed that the proposed method provides high-quality solutions with computational efficiency, significantly outperforming the best simple heuristics found in the literature.  相似文献   
997.
In the traditional GA, the tournament selection for crossover and mutation is based on the fitness of individuals. This can make convergence easy, but some useful genes may be lost. In selection, as well as fitness, we consider the different structure of each individual compared with an elite one. Some individuals are selected with many different structures, and then crossover and mutation are performed from these to generate new individuals. In this way, the GA can increase diversification into search spaces so that it can find a better solution. One promising application of GA is evolvable hardware (EHW), which is a new research field to synthesize an optimal circuit. We propose an optimal circuit design by using a GA with a different structure selection (GAdss), and with a fitness function composed of circuit complexity, power, and signal delay. Its effectiveness is shown by simulations. From the results, we can see that the best elite fitness, the average fitness value of correct circuits, and the number of correct circuits with GAdss are better than with GA. The best case of optimal circuits generated by GAdss is 8.1% better in evaluation value than that by traditional GA.  相似文献   
998.
In this study, we mapped seagrass beds in Japanese coastal areas by using a newly developed combination method of satellite and side‐scan sonar images. Traditionally, sea‐truth data used for satellite‐image analysis are collected through direct observations requiring scuba divers or by aquatic video‐camera observation. The method proposed here used side‐scan sonar measurements for collecting accurate sea‐truth data and succeeded in efficiently obtaining precise information about seagrass distribution. Side‐scan sonar images also enabled us to assess the reliability of satellite‐image results from an area perspective and not only from a traditional point data one. The IKONOS image was analysed in two different ways. First, mapping was realized without any reference to bottom depth. Second, mapping was processed with consideration for depth gradients. Results were compared using error matrices and showed that the method proposed here is suitable to map several specific areas efficiently.  相似文献   
999.
In a musculoskeletal system like a tendon-driven robot, redundant actuation is necessary because muscles (or mechanical parts such as tendons) can transmit tension only unidirectionally. This redundancy yields internal force among muscles, which has a particular field of potential energy. Using internal force as a feedforward input, a musculoskeletal system can achieve feedforward position control with no sensory feedback. This paper studies the feedforward position control coming from the redundancy for a non-pulley musculoskeletal system. Targeting a planar two-link system with six muscles as a case study, the motion convergence depending on the muscular arrangement is examined quasi-statically. The results point out that the convergence is extremely sensitive to the muscular arrangement, and adding small offsets for the muscular connected points can remarkably improve the positioning performance.  相似文献   
1000.
Proteome analysis of bladder cancer with narrow-range pH 2-DE has identified a novel protein on chromosome 7 encoded by ORF 24 (C7orf24) as one of the highly expressed proteins in cancer cells. C7orf24 is currently registered in the protein database as a hypothetical protein with unknown function. The homologs of C7orf24 in other animals have also been registered as putative protein genes. Western blot analysis using a mAb against C7orf24 confirmed its higher expression in bladder cancer compared with normal tissue. Several other cancer cell lines were also found to express C7orf24. However, the introduction of C7orf24 into Rat-1 or NIH3T3 cells did not cause malignant transformation. A stable transfectant of NIH3T3 cells with recombinant retrovirus vector was produced for a growth rate assay, and a higher growth rate was observed in C7orf24-expressing cells compared with the controls. Six kinds of small interfering RNAs (siRNAs) were then produced, and C7orf24-siRNA#5 showed a strong knockdown effect on protein expression and significant antiproliferative effects on cancer cell lines were demonstrated by the MTT assay. Therefore, C7orf24 may have an important role in cancer cell proliferation, and may be an appropriate therapeutic target molecule against cancer.  相似文献   
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