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11.
This paper develops a concept of Panoramic Appearance Map (PAM) for performing person reidentification in a multi-camera setup. Each person is tracked in multiple cameras and the position on the floor plan is determined using triangulation. Using the geometry of the cameras and the person location, a panoramic map centered at the person’s location is created with the horizontal axis representing the azimuth angle and vertical axis representing the height. Each pixel in the map image gets color information from the cameras which can observe it. The maps between different tracks are compared using a distance measure based on weighted SSD in order to select the best match. Temporalintegration by registering multiple maps over the tracking period improves the matching performance. Experimental results of matching persons between two camera sets show the effectiveness of the approach. This work has been sponsored by the Technical Support Working Group (TSWG) of US Department of Defence (DoD).  相似文献   
12.
Microsystems technology is an emerging technology that is used in ever more technical systems, such as inkjet nozzles or accelerometers. 3D micromechanical structures became feasible by miniaturizing macromechanical elements. One big challenge in downsizing mechanical elements is to adapt conventional manufacturing technologies to the conditions of microtechnology. Integrated design and production processes must be suited to the new requirements, in-depth knowledge of production technology is required to design micromechanical components. Since 2000, the Collaborative Research Center 499 “Design, Production and Quality Assurance of Molded Microcomponents made of Metallic and Ceramic Materials” has been focusing on a continuous and stable process chain for molded micro components (Albers et al. 2005, Microsyst Technol). The aim of prior funding periods was to develop the knowledge about how components, such as gearwheels, and systems, such as micro gears, can be designed. Present research is focused on how to design functional elements, i.e. shaft-hub joints to transmit torque. This paper will introduce an approach that generates know-how via testing several plain bearings and shaft-hub joints in order to derive the necessary know-how to develop simulation tools later on.  相似文献   
13.
The aim of the present paper is the development of endodontic Cu-based single crystal Shape Memory Alloy (SMA) instruments in order to eliminate the antimicrobial and mechanical deficiencies observed with the conventional Nickel-Titane (NiTi) SMA files. A thermomechanical constitutive law, already developed and implemented in a finite element code by our research group, is adopted for the simulation of the single crystal SMA behavior. The corresponding material parameters were identified starting from experimental results for a tensile test at room temperature. A computer-aided design geometry has been achieved and considered for a finite element structural analysis of the endodontic Cu-based single crystal SMA files. They are meshed with tetrahedral continuum elements to improve the computation time and the accuracy of results. The geometric parameters tested in this study are the length of the active blade, the rod length, the pitch, the taper, the tip diameter, and the rod diameter. For each set of adopted parameters, a finite element model is built and tested in a combined bending-torsion loading in accordance with ISO 3630-1 norm. The numerical analysis based on finite element procedure allowed purposing an optimal geometry suitable for Cu-based single crystal SMA endodontic files. The same analysis was carried out for the classical NiTi SMA files and a comparison was made between the two kinds of files. It showed that Cu-based single crystal SMA files are less stiff than the NiTi files. The Cu-based endodontic files could be used to improve the root canal treatments. However, the finite element analysis brought out the need for further investigation based on experiments.  相似文献   
14.
Several techniques can be used to improve surface properties of metals. These can involve changes on the surface chemical composition such as alloying or on the surface microstructure, such as hardening. In the present work, melting of the surface by a 9 kW CO2 CW laser of wavelength 10.6 μm was used to alter surface features of D2 tool steel. Carbon powder and nitrogen gas were used as sources of alloying elements during laser processing. The effect of various laser parameters (power and speed) on the microstructure and hardness of D2 tool steel was investigated. Laser powers from 1 to 8 kW and laser speeds from 5 to 15 mm/s were employed. It was found that as the laser power increases, the hardness of the melted zone decreases while that of the heat-affected zone increases. On the other hand, the depth of both of melted and heat-affected zones increases with power.  相似文献   
15.
Drying of textiles is one of the energy‐intensive unit operations and stenters are the most widely used drying machines in textile finishing mills. This study reveals energetic and exergetic analysis of a stenter system in a textile finishing factory based on actual operational data. The system includes a stenter along with its circulating and induced draft fans, a hot oil boiler and an oil circulating pump. The exergy destructions in each of the components of the overall systems were determined for average values of experimentally measured parameters. Exergy efficiencies of the system components were determined which help in assessing their performance and to establish strategies for improvement. The exergetic efficiencies of the stenter and hot oil boiler were found to be 28.7 and 34.7%, respectively, while the overall exergy efficiency of the system was obtained to be 34.4%. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
16.
参与消费电子细分市场,会带来许多优势。尽管如此,该细分市场的设计团队仍将面临急剧收缩的上市时间窗口。因此,基于FPGA的设计已经演变成为许多系统体系结构设计者的首选。同时,人们对消费品中的多媒体功能的需求日益增多,这使得DSP和流传输接口成为许多嵌入式产品中必备的部件。几家FPGA厂商开发了带有DSP核心与流传输接口的FPGA,它们在技术和复杂度上均足以应对最近这些设计要求。  相似文献   
17.
18.
This study was carried out on very steep and difficult terrain. Whole trees were logged uphill to the forest road by a Koller K300 cable crane. Investigations were carried out by time studies for which the repetition time measurement method was selected. Through time studies, the productivity and cost of the Koller cable system were evaluated.  相似文献   
19.
Thermal conductivity variations with temperature for solid phases in the Urea (U)–[X] mol pct 4-bromo-2-nitroaniline (BNA) system (X = 0, 2, 45, 89.9, and 100) were measured using the radial heat flow method. From graphs of thermal conductivity variations with temperature, the thermal conductivities of the solid phases at their melting temperature and temperature coefficients for the U–[X] mol pct BNA system (X  =  0, 2, 45, 89.9, and 100) were found to be 0.26, 0.55, 0.46, 0.38, and 0.23 W/Km and 0.007781, 0.005552, 0.002058, 0.002188, and 0.002811 K?1, respectively. The ratios of thermal conductivity of the liquid phase to thermal conductivity of the solid phase in the U–[X] mol pct BNA system (X  =  0, 2, 45, 89.9, and 100) were also measured to be 0.30, 0.44, 0.46, 0.49, and 0.51, respectively, with a Bridgman-type directional solidification apparatus at their melting temperature.  相似文献   
20.
The grain boundary groove shapes for solid neopentylglycol solution (NPG-40 mol pct AMPD) in equilibrium with the neopentylglycol (NPG)–aminomethylpropanediol (AMPD) eutectic liquid (NPG-42.2 mol pct AMPD) have been directly observed using a horizontal linear temperature gradient apparatus. From the observed grain boundary groove shapes, the Gibbs–Thomson coefficient (Г) and solid–liquid interfacial energy (σ SL) of solid NPG solution have been determined to be (7.4 ± 0.7) × 10?8 K m and (6.4 ± 1.0) × 10?3 J m?2, respectively. The grain boundary energy of solid NPG solution has been determined to be (12.5 ± 1.0) × 10?3 J m?2 from the observed grain boundary groove shapes. The ratio of thermal conductivity of equilibrated eutectic liquid to thermal conductivity of solid NPG solution has also been determined to be 0.48.  相似文献   
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