首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1313篇
  免费   47篇
  国内免费   2篇
电工技术   10篇
化学工业   238篇
金属工艺   125篇
机械仪表   95篇
建筑科学   33篇
矿业工程   1篇
能源动力   45篇
轻工业   47篇
水利工程   3篇
无线电   147篇
一般工业技术   222篇
冶金工业   263篇
原子能技术   23篇
自动化技术   110篇
  2023年   8篇
  2022年   21篇
  2021年   36篇
  2020年   25篇
  2019年   44篇
  2018年   36篇
  2017年   42篇
  2016年   36篇
  2015年   20篇
  2014年   51篇
  2013年   62篇
  2012年   79篇
  2011年   80篇
  2010年   52篇
  2009年   65篇
  2008年   57篇
  2007年   68篇
  2006年   53篇
  2005年   39篇
  2004年   45篇
  2003年   38篇
  2002年   39篇
  2001年   29篇
  2000年   28篇
  1999年   33篇
  1998年   44篇
  1997年   41篇
  1996年   15篇
  1995年   19篇
  1994年   13篇
  1993年   11篇
  1992年   6篇
  1991年   8篇
  1990年   18篇
  1989年   13篇
  1988年   7篇
  1987年   6篇
  1986年   4篇
  1985年   16篇
  1984年   9篇
  1983年   8篇
  1982年   4篇
  1981年   3篇
  1980年   4篇
  1979年   6篇
  1978年   5篇
  1977年   3篇
  1976年   2篇
  1973年   3篇
  1972年   2篇
排序方式: 共有1362条查询结果,搜索用时 0 毫秒
101.
This paper presents a novel method for cost aggregation and occlusion handling for stereo matching. In order to estimate optimal cost, given a per-pixel difference image as observed data, we define an energy function and solve the minimization problem by solving the iterative equation with the numerical method. We improve performance and increase the convergence rate by using several acceleration techniques such as the Gauss-Seidel method, the multiscale approach, and adaptive interpolation. The proposed method is computationally efficient since it does not use color segmentation or any global optimization techniques. For occlusion handling, which has not been performed effectively by any conventional cost aggregation approaches, we combine the occlusion problem with the proposed minimization scheme. Asymmetric information is used so that few additional computational loads are necessary. Experimental results show that performance is comparable to that of many state-of-the-art methods. The proposed method is in fact the most successful among all cost aggregation methods based on standard stereo test beds.  相似文献   
102.
A mathematical model has been developed to describe the various processes occurring in a flash furnace shaft. The model incorporates turbulent fluid dynamics, chemical reaction kinetics, and heat and mass transfer. The key features include the use of thek-ε turbulence model, incorporating the effect of particles on the turbulence, and the four-flux model for radiative heat transfer. The model predictions were compared with measurements obtained in a laboratory flash furnace and a pilot plant flash furnace. Good agreement was obtained between the predicted and measured data in terms of the SO2 and O2 concentrations, the amount of sulfur remaining in the particles, and the gas temperature. Model predictions show that the reactions of sulfide particles are mostly completed within about 1 m of the burner, and the double-entry burner system with radial feeding of the concentrate particles gives better performance than the singleentry burner system. The model thus verified was used to further predict various aspects of industrial flash furnace operation. The results indicate that from the viewpoint of sulfide oxidation, smelting rate can be substantially increased in most existing industrial flash furnaces. Formerly Graduate Student, Department of Metallurgical Engineering, University of Utah.  相似文献   
103.
A mathematical model has been developed to describe the rate processes in an axisymmetric copper flash smelting furnace shaft. A particular feature of the model is the incorporation of the four-flux model to describe the radiative heat transfer by combining the absorbing, emitting, and anisotropic scattering phenomena. The importance of various subprocesses of the radiative heat transfer in a flash smelting furnace has been studied. Model predictions showed that the radiation from the furnace walls and between the particles and the surrounding is the dominant mode of heat transfer in a flash smelting furnace. Formerly Graduate Student, Department of Metallurgical Engineering, University of Utah.  相似文献   
104.
The effects of steaming time (6, 8, and 10 min), freezing storage period, and re-steaming for thawing on the textural properties of non-glutinous rice cakes (baekseolgi) were investigated. As the steaming time increased, the rice cakes softened. In particular, the sample that was steamed for 10 min showed lower hardness than those steamed for shorter periods. A short period of steaming was insufficient for water bound to the surface of the starch granules to penetrate the granules in the dough. During the re-steaming process of the frozen non-glutinous rice cake samples, the retrogradation of starch and water syneresis contributed to the increased hardness of non-glutinous rice cakes.  相似文献   
105.
An air core is generated during draining after rotating cylindrical tanks filled with liquid. Air cores have a complex flow structure including rotational motion and a change in the free surface shape. In addition, the generation and extinction of air cores are dependent on the initial rotating speed, the dimensions of the tank, and the liquid materials. This phenomenon is usually detected in various applications for different fields such as the flow in the tundish discharging process of the smelting process, the liquid fuel system of rockets, from the suction of pumps, and so on. In this study, the flow structures including the drain time, the change in the free surface shape, velocity field, and vorticity distributions are numerically and experimentally investigated. Both the numerically and experimentally results were in good agreement with each other with respect to the drain time.  相似文献   
106.
Journal of Mechanical Science and Technology - The importance of equipment technology for semiconductor mass production is growing as well as the exponential increase in demand for semiconductors....  相似文献   
107.
Food Science and Biotechnology - Chronic diabetes mellitus (DM) can cause liver dysfunction and other complications. As Humulus japonicus is known to have anti-inflammatory and antioxidative...  相似文献   
108.
MOX fuel rod behavior due to PCMI during power transients was evaluated using a finite element code, ABAQUS. Clad elongation is calculated through a coupled temperature–displacement analysis where a half-pellet is axisymmetrically modeled. Parametric study for the PCMI model is preliminary performed to identify the dominant factors and examine the applicable range of the model. The comparison of the predicted results with recent MOX in-pile data shows that the centerline temperature and clad elongation are evaluated within an acceptable range.  相似文献   
109.
In the present study, we demonstrated that fluorescent dyes could be nanoscopically dispersed in a polymer matrix that was immiscible with the dyes; the dyes were encapsulated in micelles. Using a model polymer composite, we also showed that the color of light emitted by light-emitting diodes (LEDs) could be controlled by coating fluorescent polymer composites onto the LEDs. For this purpose, fluorophores that were insoluble in toluene were solubilized into a solution of block copolymer micelles in toluene by the selective incorporation of fluorescent dyes into micellar cores. Because the micelles could be dispersed well in the polymer matrix without the formation of aggregates, fluorescent dyes encapsulated in the micelles were also effectively dispersed in the polymer matrix without macroscopic separation. The polymer composite can be evenly coated onto most substrates, regardless of their surface characteristics. Thus, light-emitting devices with well-controlled emission wavelengths and emission intensities can be fabricated by coating the polymer composite onto the surface of the device.  相似文献   
110.
Glass-ceramics containing cordierite (2MgO-2Al2O3-5SiO2) as a crystal phase based on the glasses in the system MgO-Al2O3-SiO2 were investigated for the application to magnetic disk substrate for higher storage capacity. Parent glasses were prepared with CeO2 addition as a flux and were crystallized by a controlled 2-step heat treatment The maximum nucleation and crystal growth rates were 2.4 × 109/mm3 · hr at 800 °C and 0.3 m/hr at 915°C respectively. Only - cordierite was precipitated after heat-treatment. After nucleation at 800 °C for 5 hours prior to crystallization at 915 °C for 1 hour, the resulting crystal volume fraction and crystal size were 17.6% and 0.3 m, respectively. Heat-treated specimens through the above condition showed the optimum properties for magnetic memory disk substrates as follows.; Bending strength of 192 MPa, Vickers hardness of 642.1 kg/mm2, thermal expansion coefficient of 39 × 10–7/K and surface roughness of 27 Å.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号