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101.
We have developed a meter-scale light emitting diode (LED)-embedded light fabric and its weaving machine for application to a light device for fabric ceilings, which have recently become desired for lightweight safe ceilings in Japan and other countries with frequent earthquakes. The LED fabric structure is 1.2-m-wide woven fabric that has 5-mm-wide LED chip-mounted printed circuit board (PCB) tapes as wefts. LEDs are mounted on the tape of PCBs with a reel-to-reel chip mounting system. Then, the LED-mounted tapes are woven with a developed automatic looming machine that aligns the weft with an accuracy of 0.9 mm, which is suitable for precise arrangement of LEDs and wiring to power supply. A 1.2 × 1.2 m LED-embedded light fabric weighing 320 g/m2 was woven. The luminance of the LED fabric is 353 lx at a distance of 1 m, which is the luminance of conventional office lighting. The temperature increase of LEDs without a rigid cooling aluminum plate is only 5.8 °C, and the LED fabric is flexible enough to sustain 1,000 bends down to a radius of 3 mm. This LED fabric and its weaving technology will lead to light devices that have lightweight, large area, and high flexibility for fabric ceilings, walls, and other large areas in homes and offices. 相似文献
102.
Ryosuke Harakawa Takahiro Ogawa Miki Haseyama 《Multimedia Tools and Applications》2018,77(16):20297-20324
A method to track topic evolution via salient keyword matching with consideration of semantic broadness for Web video discovery is presented in this paper. The proposed method enables users to understand the evolution of topics over time for discovering Web videos in which they are interested. A framework that enables extraction and tracking of the hierarchical structure, which contains Web video groups with various degrees of semantic broadness, is newly derived as follows: Based on network analysis using multimodal features, i.e., features of video contents and metadata, our method extracts the hierarchical structure and salient keywords that represent contents of each Web video group. Moreover, salient keyword matching, which is newly developed by considering salient keyword distribution, semantic broadness of each Web video group and initial topic relevance, is applied to each hierarchical structure obtained in different time stamps. Unlike methods in previous works, by considering the semantic broadness as well as the salient keyword distribution, our method can overcome the problem of the desired semantic broadness of topics being different depending on each user. Also, the initial topic relevance enables correction of the gap from an initial topic at the start of tracking. Consequently, it becomes feasible to track the evolution of topics over time for finding Web videos in which the users are interested. Experimental results for real-world datasets containing YouTube videos verify the effectiveness of the proposed method. 相似文献
103.
Langmuir–Blodgett (LB) films of the copolymer with ferrocenyl-methyl-acrylate (FcMA) and N-dodecyl-acrylamide (DDA) were fabricated. The magnetic moment of these LB films became about twenty times larger than that of the powder. In addition, the LB films had a magnetic anisotropy depending on the dipping direction. The FTIR results suggested that the polymer chains in the LB films were preferably aligned with the perpendicular of the dipping direction. These results were discussed by the intermolecular electron transfer. 相似文献
104.
Under magnetic fields perpendicular to the conductive plane in quasi-two-dimensional organic conductors: -(BEDT-TTF)2
MHg(SCN)4 (M= K, Rb, and Tl), the experimentally reported H–T phase diagram has been explained partially. By the self-consistent numerical calculation including the quantum magnetic oscillation and the magnetic breakdown; in addition to the imperfectness of the SDW nesting, we try to completely understand the phase diagram. 相似文献
105.
Reo Matsumura Masahiro Shiomi Takahiro Miyashita Hiroshi Ishiguro Norihiro Hagita 《Advanced Robotics》2015,29(7):469-480
This study addresses a floor identification method for small humanoid robots that work in such daily environments as homes. The fundamental difficulty lays in a method to understand the physical properties of floors. To achieve floor identification with small humanoid robots, we used inertial sensors that can be easily installed on such robots, and dynamically selected a full-body motion that physically senses floors to achieve accurate floor identification. We collected a training data-set over 10 different kinds of common floors in home environments. We achieved 85.7% precision with our proposed method. We also demonstrate that our robot could appropriately change its locomotion behaviours depending on the floor identification results. 相似文献
106.
We have developed a reel-to-reel microchip mounting system that continuously mounts LED chips and other microchips on meter-long flexible printed circuit board (PCB) tape for 1.2-m-long standard LED light tubes. Mounting microchips on meter-long PCBs is difficult because a large chip mounter is expensive and the chip positioning stage is difficult to move in a meter-wide area with an accuracy of hundreds of micrometers. Hence, we developed a new microchip mounting system that utilizes a small chip mounter and reel winding machines. The system repeatedly moves the long PCB tape by a certain length with the reel winding machines and mounts the chips on it. The PCB tape (which is 5 mm wide) is made by fabricating long PCB tapes which are 25 cm × 26.6 m through a roll-to-roll PCB process and slitting them into meter-long tapes. The reel-to-reel system repeatedly mounts chips by adjusting their positions through image processing of the copper wiring pattern on the PCBs. Our constructed system mounted 24 LED chips with a pitch of 5 cm with an accuracy of 0.082 mm to form a 1.2-m-long LED tape. The luminance of the tape is 12.4 lx at a distance of 1 m, which is the luminance of outdoor corridor lighting. Therefore, this system can be used for meter-long tape lighting. 相似文献
107.
A manufacturing XML schema definition and its application to a data management system on the shop floor 总被引:1,自引:0,他引:1
Digitization for sharing knowledge on the shop floor in the machinery industry has been given much attention recently. To help engineers use digitization practically and efficiently, this paper proposes a method based on manufacturing case data that has a direct relation to manufacturing operations. The data are represented in XML schema, as it can be easily applied to Web-based systems on the shop floor. The definitions were made for eight manufacturing methods including machining and welding. The derived definitions consist of four divisions of metadata, work-piece, process and evaluation. Three divisions except for the “process” division are common to the manufacturing methods. The average number of elements for a manufacturing method is about 200. The represented schema is also used to convey knowledge such as operation standards and manufacturing troubleshooting on the shop floor. Using the definitions, a data management system is developed. It is a Web-based Q&A system, in which the engineers specify the manufacturing case data mainly by selecting from the candidates. Then, the system fills in the blank portions and/or shows messages to help complete the case data. The proposed method is evaluated through practical scenarios of arc welding and machining. 相似文献
108.
Xiufeng HAN Lanying LIN T.Miyazaki Fuming YANG Rengeng XU Xinhua WANG Hongge PAN Changping CHEN 《材料科学技术学报》1999,15(1):5-9
1.IntroductionIntensiveinvestigatiOnsontheR-Fe-T(R=rareearth,T=transitionmetalasastabilizingelement)phasediagrams,locatedattheironrichcorner,ledtothediscoveryofthenovelR2(Fe,T)l9phase[1l2]duetothegreatinterestinhighperfOrmanceper-manentmagneticmaterials.ItsrealstoichiometriccompOsitionandcrystallographicstructurewerede-terminedasaNd3(Fe,Ti)29-typestructurewithmon-oclinicsymmetry[3]andtheA2/mspacegrOup[4]byX-rnypowderdiffractiOn(XRD)andthenthiswasconfirmedbyneutrOnpOwderdiffraction[5'6… 相似文献
109.
介绍了红外相机CASCAM的电动系统设计。系统采用AT90S8515单片机和TA8435集成芯片组成驱动电路的核心,通过电机选择电路和位置反馈电路实现对步进电机的选择驱动和定位、复位。系统采用MAXIM232芯片实现单片机和上位机之间的串行通讯。系统软件以汇编语言编制,并给出了系统程序框图。经实验验证,该系统运行可靠,达到了设计要求。 相似文献
110.
Human behaviors consist of both voluntary and involuntary motions. Almost all behaviors of task-oriented robots, however, consist solely of voluntary motions. Involuntary motions are important for generating natural motions like those of humans. Thus, we propose a natural behavior generation method for humanoid robots that is a hybrid generation between voluntary and involuntary motions. The key idea of our method is to control robots with a hybrid controller that combines the functions of a communication behavior controller and body balancing controllers. We also develop a wheeled inverted pendulum type of humanoid robot, named “Robovie-III”, in order to generate involuntary motions like oscillation. By applying our method to this robot and conducting preliminary experiments, we verify its validity. Experimental results show that the robot generates both voluntary and involuntary motions. 相似文献