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991.
The heat transfer characteristics and flow behavior in a rectangular passage with two opposite 45° skewed ribs for turbine rotor blade have been investigated for Reynolds numbers from 7800 to 19,000. In this blade, the spanwise coolant passage at the trailing edge region whose thickness is very thin is chosen, so the channel aspect ratio (=width/height of channel) is extremely high, 4.76. Therefore the heat transfer experiment in the high‐aspect‐ratio cooling channel was performed using thermochromic liquid crystal and thermocouples. Furthermore, the calculation of flow and heat transfer was carried out using CFD analysis code to understand the heat transfer experimental results. The enhanced heat transfer coefficients on the smooth side wall at the rib's leading end were the same level as those on the rib‐roughened walls. © 2002 Scripta Technica, Heat Trans Asian Res, 31(2): 89–104, 2002; DOI 10.1002/htj.10018 相似文献
992.
Ebesutani Chad; Okamura Kelsie; Higa-McMillan Charmaine; Chorpita Bruce F. 《Canadian Metallurgical Quarterly》2011,23(2):406
The current study was the 1st to examine the psychometric properties of the Positive and Negative Affect Schedule for Children–Parent Version (PANAS-C-P) using a large school-based sample of children and adolescents ages 8 to 18 (N = 606). Confirmatory factor analysis supported a 2-factor (correlated) model of positive affect (PA) and negative affect (NA). The PANAS-C-P scale scores also demonstrated acceptable internal consistency and convergent and divergent validity. The PANAS-C-P PA and NA scale scores also related to measures of anxiety and depression in a manner consistent with the tripartite model. Scale means and standard deviations were reported by grade and sex to provide normative data for the PANAS-C-P scales. Results from the present study provide initial support for the PANAS-C-P as a parent-reported perspective of youth PA and NA among school-based youths. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
993.
We analyse the seemingly unrelated regression (SUR) models with spatial dependencies from a Bayesian point of view and estimate the parameters of the models using a Markov chain Monte Carlo (MCMC) method. Further, we analyse the production technology and the economics of agglomeration in Japanese prefectures from 1991 to 2000, simultaneously taking into account spatial and serial correlation. Model comparison is done via log‐marginal likelihoods, and it is found that the spatial error SUR model is the best model and that the economics of agglomeration and spatial heterogeneity decreased over this decade. Resumen. Analizamos modelos de ecuaciones aparentemente no relacionadas (SUR, siglas en inglés) con dependencias espaciales desde un punto de vista bayesiano y estimamos los parámetros de los modelos utilizando el método de Monte Carlo basado en cadenas de Markov (MCMC). Además, analizamos la tecnología de la producción y las economías de aglomeración en prefecturas japonesas desde 1991 a 2000, teniendo en cuenta simultáneamente la correlación espacial y serial. La comparación de modelos se realiza mediante verosimilitud log‐marginal, y se encontró que el error espacial del modelo SUR es el mejor modelo y que las economías de aglomeración y la heterogeneidad espacial disminuyeron durante esta década. 相似文献
994.
Arthorn Sanpanich Kazuhiko Hamamoto Chuchart Pintavirooj 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(Z1):S105-S113
Breast cancer is one of the most prevalent health hazards in women all over the world. An annual screening test using a diagnostic ultrasound seems to be an appropriate method to handle this physical threat. In this paper, we propose the use of a two‐dimensional reflection‐mode ultrasonic tomography system for a general breast ultrasound investigation enhanced by an echo wave path using a wave reflecting plate. Our virtual imaging setup system is composed of a 128‐element conventional linear array transducer placed on the top of a water bath and a wave reflector attached around this setup. The shape of the wave reflector was designed as a single plate shape, rectangular shape and curve shape. For projection data, we estimate a line integral insonifying data by using a classical integration slope of attenuation coefficient method in which its derivative is independent of transmittance, reflectance, and noise. By imaging a virtual breast phantom model, the reconstruction results obtained from an iterative algebraic reconstruction technique (ART) algorithm show a promising image. The image is not only indicates a tissue characterization from quantitative attenuation data, but also restores an area covered by hard tissue due to an increased wave path direction from our nonrotational imaging system. These results encourage us to implement our concept with a clinical study in the near future. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
995.
Shotaro Miwa Hiroshi Kage Kazuhiko Sumi 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(6):607-612
This paper describes a context‐based robust face detection algorithm for surveillance cameras. Different from familiar faces captured by digital cameras, faces captured by surveillance cameras are smaller and darker with motion blurs and distortions. Furthermore, captured from top‐mounted cameras, facial images are downward and partially hidden. Just using a single‐face detector to detect such degraded faces is very difficult. To solve the problem, we utilize contextual information about faces of walking people. We employ a probabilistic face detection framework combining a face detector with local and global contextual information. We use a boosted fast face detector as an initial selector to pick up a small number of possible face regions in a very short time. After the fast selection of candidate face patches, as local contextual information we calculate a conditional probability in the surrounding regions using a histogram of oriented gradient (HOG) feature‐based outline detector, and as global contextual information we calculate possible face patches from viewpoint information using vanishing point detection. Combining a fast boosted face detector with these contextual information, while keeping computational efficiency of the original boosted face detector, we achieved a high face detection rate of 93.7% with about 1000 times lower false‐positive rate than when using a single original face detector. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
996.
本文介绍了一种新型自动进样器,能够将收集到的样品直接进样到色谱柱,而不用任何流路转换装置或额外的管路连接。除了需要常规自动进样器的六通切换阀,还设计了一个直接进样阀(DIV)用于自动进样器。六通阀和DIV的同步协调运行使得建立一个简单的样品流路和连续流体经过分离柱的系统成为可能。这种自动进样器的结构具有减小样品引入造成的谱带展宽和防止样品过载的特点。 相似文献
997.
S Yamamoto M Zaitsu E Ishii H Yatsuki S Mizutani M Eguchi K Ihara T Okamura T Hara S Miyazaki 《Canadian Metallurgical Quarterly》1998,12(9):1398-1403
998.
Degree of Saturation and Liquefaction Resistances of Sand Improved with Sand Compaction Pile 总被引:1,自引:0,他引:1
Mitsu Okamura Masanori Ishihara Keiichi Tamura 《Canadian Metallurgical Quarterly》2006,132(2):258-264
Sand compaction pile (SCP) is a ground improvement technique extensively used to ameliorate liquefaction resistance of loose sand deposits. This paper discusses results of laboratory tests on high-quality undisturbed samples obtained by the in situ freezing method at six sites where foundation soils had been improved with SCP. Inspection of samples revealed that the improved ground was desaturated during the ground improvement. Degree of saturation (Sr) was lower than 77% for the sand piles and 91% for the improved sand layers, while Sr was approximately 100% for improved clayey and silty soils. A good correlation was found between Sr and 5% diameter of the soil; the larger 5% diameter of soils (D5), the lower the degree of saturation. It appeared that the variation of Sr with D5 for soils within a month after the ground improvement work was quite similar in trend to that after more than several years. Degree of saturation of soils after several years was noticeably, but not significantly, higher as compared with that shortly after ground improvement, indicating longevity of air bubbles injected in the improved soil. Undrained cyclic shear tests were also carried out on saturated and unsaturated specimens and effects of desaturation on undrained cyclic shear strength were studied. The test results were summarized in a form of liquefaction resistance with reference to normalized standard penetration test N-value. 相似文献
999.
Toshio Shimoo Ichiro Tsukada Tadao Seguchi Kiyohito Okamura 《Journal of the American Ceramic Society》1999,82(12):3508-3512
The low-oxygen SiC fiber fabricated by the electron-beam irradiation curing method, Hi-Nicalon, was heated at 1773 to 2273 K in a hot isostatic press (800 MPa of argon) and was subsequently reheated at 1873 K at 1 atm (101 kPa) of argon. The hot isostatic press treatment delayed the onset of fiber deterioration to higher temperature. The fiber strength remained almost unchanged by subsequent reheating at 1873 K in 101 kPa of argon. The thermal stability of Hi-Nicalon, as a consequence of the permanent change in surface structure, can be greatly improved by treating in the hot isostatic press. 相似文献
1000.
Mitsuo Miyazawa Shigeaki Okamura Hiromu Kameoka 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1999,74(5):399-402
The microbial transformations of 2,6‐ and 3,5‐dimethylcyclohexanone were investigated using the plant pathogenic fungus, Glomerella cingulata. With this organism 2,6‐ and 3,5‐dimethylcyclohexanone gave the corresponding 2,6‐ and 3,5‐dimethylcyclohexanol. The metabolites from 2,6‐dimethylcyclohexanone indicated enantioselective reduction by specific optical rotation of the products. The enantiomeric excesses of the microbiological reduction products were determined by 1H‐NMR spectra of (+)‐MTPA‐esters of the alcohols produced. The reduction of 2,6‐dimethylcyclohexanone was stereospecific, with the (2R,6R)‐ketone being converted to the corresponding (2R,6R)‐(−)‐2,6‐dimethylcyclohexanol; absolute configuration, 70% ee. On the other hand, 3,5‐dimethylcyclohexanone gave the (1α,3α,5α)‐3,5‐dimethylcyclohexanol (74%) and (1α,3β,5β)‐3,5‐dimethylcyclohexanol (26%). © 1999 Society of Chemical Industry 相似文献