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71.
The relationship between the structure and the compressive strength of carbon fibres has been studied in detail. In order to determine the compressive strength, a combination of single-fibre composite tests and Raman spectroscopy was employed. It was found that the compressive stress–strain curves showed nonlinear behaviour, with modulus softening in compression. The compressive strengths for the fibres with a modulus ≥400 GPa were measured as ≤2 GPa and those with a modulus <400 GPa were >2 GPa. We have introduced a model to explain this behaviour that assumes that the fibres behave as composites consisting of both crystallites and amorphous carbon. It is suggested that the compressive strength is controlled by the critical stress for kinking the crystallites in the fibres. Hence, the compressive strength of carbon fibres is found to depend upon the shear modulus of the fibres and the orientation of the crystallites within them.  相似文献   
72.
Recently, there has been considerable interest in various renewable energies. Among them, solar cell production has increased markedly because the photovoltaic is a clean and safe power generation method. The dye-sensitized solar cell (DSSC) has attracted much attention as an alternative to silicon solar cells due to lower manufacturing costs and plentiful resources for DSSC production. However, the performance of DSSCs has been limited by their durability and low photoelectric conversion efficiency. Temperature control of DSSCs via phase-change materials (PCMs) is expected to improve performance. In this study, DSSCs were heated or cooled with a heat exchanger copper block that was in contact with a PCM (heptadecane), while being irradiated by a solar simulator light source. The durability and photoelectric conversion efficiency of the DSSC improved under PCM temperature control.  相似文献   
73.
We report here an autopsy case of Binswanger's disease (BD) without hypertension and associated with cerebral infarction in the terminal stage. The female patient, who was 74 years old at the time of death, had initially demonstrated manic-depressive disorder-like mental disorder, followed by dementia and neurological deficits. A brain CT scan showed white matter low attenuation bilaterally and symmetrically. BD was clinically diagnosed despite the lack of hypertension. In the terminal stage, she suffered an infarction in the left anterior cerebral artery region, and died of pneumonia. Neuropathologically, we found the infarction of the left anterior cerebral artery region, demyelination, fibrillary gliosis, lacunae and arteriosclerosis of the small arteries and arterioles in the white matter.  相似文献   
74.
A conflict between accommodation and vergence is one possible cause of visual fatigue and discomfort while viewing conventional three‐dimensional displays. Previous studies have proposed the super multi‐view (SMV) display technique to solve the vergence–accommodation conflict, in which two or more parallax images enter the pupil of the eye with highly directional rays. We simultaneously measured accommodative, vergence, and pupillary responses to SMV three‐dimensional displays to examine whether they can reduce the conflict. For comparison, responses to two‐view stereo images and real objects were also measured. The results show that the range of the accommodative response was increased by the SMV images compared with the two‐view images. The slope of the accommodation–vergence response function for the SMV images was similar to that for the real objects rather than the two‐view images. We also found that enhancement of the accommodative range by the SMV images is noticeable with binocular viewing, indicating that vergence‐induced accommodation plays an important role in viewing SMV displays. These results suggest that SMV displays induced a more natural accommodative response than did conventional, two‐view stereo displays. As a result, SMV displays reduced the vergence–accommodation conflict.  相似文献   
75.
This paper presents a new approach to search for a gas/odor source using an autonomous mobile robot. The robot is equipped with a CMOS camera, gas sensors, and airflow sensors. When no gas is present, the robot looks for a salient object in the camera image. The robot approaches any object found in the field of view, and checks it with the gas sensors to see if the object is releasing gas. On the other hand, if the robot detects the presence of gas while wandering around the area, it turns toward the direction of the wind that carries the gas. The robot then looks for any visible object in that direction. These navigation strategies are implemented into the robot under the framework of the behavior-based subsumption architecture. Experimental results on the search for a leaking bottle in an indoor environment are presented to demonstrate the validity of the navigation strategies.  相似文献   
76.
Recently, life scientists have expressed a strong need for computational power sufficient to complete their analyses within a realistic time as well as for a computational power capable of seamlessly retrieving biological data of interest from multiple and diverse bio-related databases for their research infrastructure. This need implies that life science strongly requires the benefits of advanced IT. In Japan, the Biogrid project has been promoted since 2002 toward the establishment of a next-generation research infrastructure for advanced life science. In this paper, the Biogrid strategy toward these ends is detailed along with the role and mission imposed on the Biogrid project. In addition, we present the current status of the development of the project as well as the future issues to be tackled. Haruki Nakamura, Ph.D.: He is Professor of Protein Informatics at Institute for Protein Research, Osaka University. He received his B.S., M.A. and Ph.D. from the University of Tokyo in 1975, 1977 and 1980 respectively. His research field is Biophysics and Bioinformatics, and has so far developed several original algorithms in the computational analyses of protein electrostatic features and folding dynamics. He is also a head of PDBj (Protein Data Bank Japan) to manage and develop the protein structure database, collaborating with RCSB (Research Collaboratory for Structural Bioinformatics) in USA and MSD-EBI (Macromolecular Structure Database at the European Bioinformatics Institute) in EU. Susumu Date, Ph.D.: He is Assistant Professor of the Graduate School of Information Science and Technology, Osaka University. He received his B.E., M.E. and Ph.D. degrees from Osaka University in 1997, 2000 and 2002, respectively. His research field is computer science and his current research interests include application of Grid computing and related information technologies to life sciences. He is a member of IEEE CS and IPSJ. Hideo Matsuda, Ph.D.: He is Professor of the Department of Bioinformatic Engineering, the Graduate School of Information Science and Technology, Osaka University. He received his B.S., M.Eng. and Ph.D. degrees from Kobe University in 1982, 1984 and 1987 respectively. For M.Eng. and Ph.D. degrees, he majored in computer science. His research interests include computational analysis of genomic sequences. He has been involved in the FANTOM (Functional Annotation of Mouse) Project for the functional annotation of RIKEN mouse full-length cDNA sequences. He is a member of ISCB, IEEE CS and ACM. Shinji Shimojo, Ph.D.: He received M.E. and Ph.D. degrees from Osaka University in 1983 and 1986 respectively. He was an Assistant Professor with the Department of Information and Computer Sciences, Faculty of Engineering Science at Osaka University from 1986, and an Associate Professor with Computation Center from 1991 to 1998. During the period, he also worked as a visiting researcher at the University of California, Irvine for a year. He has been Professor with Cybermedia Center (then Computation Center) at Osaka University since 1998. His current research work focus on a wide variety of multimedia applications, peer-to-peer communication networks, ubiquitous network systems and Grid technologies. He is a member of ACM, IEEE and IEICE.  相似文献   
77.
78.
In the environment of the Scanning Electron Microscope (SEM), it is necessary to establish the technology of recovering the 3D shape of a target object from the observed 2D shading image. SEM has the function to rotate the object stand to some extent. This paper uses this principle and proposes a new method to recover the object shape using two shading images taken during the rotation. The proposed method uses the optimization of the energy function using Hopfield neural network, which is based on the standard regularization theory. It is also important to give the initial vector that is close to the true optimal solution vector. Computer simulation evaluates the essential ability of the proposed method. Further, the real experiments for the SEM images are also demonstrated and discussed.  相似文献   
79.
80.
The purpose of this paper is to understand how industry organization evolves under conditions of a growing market. Since Adam Smith the traditional argument has claimed that as a market grows, a vertically disintegrated industry organization evolves, and that this enhances productivity. However, the question remains whether the market alone can select an efficient industry organization. This paper analyzes a case from the Japanese farm-engine industry of the 1950s, namely the industrial district of Okayama, where the breakthrough into disintegrated production was never achieved, despite rapid growth in the domestic market for agricultural engines. This led to the collapse of the district. The analysis shows that, if vertical disintegration requires radical changes in the technological competence of each firm, the market does not necessarily offer sufficient incentives for vertical disintegration, even under conditions of a growing market.  相似文献   
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