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排序方式: 共有725条查询结果,搜索用时 15 毫秒
721.
This paper describes the development of a non-destructive inspection method for cracks in a trolley conveyor chain, using a high-frequency electric current heater and an infrared radiation camera. This method is based on the idea that cracks affect heat conduction in the chain. When the chain is heated properly with the heater, variations in the heat conduction can be detected by monitoring the surface temperature of the chain with the infrared camera. The effectiveness of the proposed method is shown by a numerical analysis of the heat conduction in the chain. It is confirmed that the method is applicable to the chain which consists of portions with high and low emissivity, and that it is not affected by oil mixed with wear debris on the chain surface or by the operation speed of the conveyor.  相似文献   
722.
At present, there is a growing demand for energy saving to prevent global warming. Thus, the railway industry is also focusing on energy saving methods. Power consumption of running trains has a large variation of approximately 20% caused by drivers’ operation. Therefore, improving the running profile can considerably reduce energy consumption. Numerous algorithms for generating energy saving running profiles have been researched and developed. To adapt energy saving operation to various environments, we developed a technology that maintains punctuality without reducing the energy efficiency when temporary differences occur in driving conditions. We propose a method that determines the re-creation command point to complete the re-creation at the switching point of the driving operation in the existing energy-saving target pattern, to achieve both punctuality and ride comfort. As a result of verifying the effect of the proposed method on the conventional method via a simulation, it was confirmed that the proposed method can prevent the increase in the number of operation changes when the driving conditions change, whereas the conventional method increases the number of operation changes.  相似文献   
723.
Artificial Life and Robotics - In this paper, using image processing and distance measurement, we develop a control system for automatic grasping and obstacle avoidance by a mobile robot. First,...  相似文献   
724.
Silica–titania mixed oxides have excellent properties, such as a low thermal expansion coefficient and a refractive index that can be adjusted by changing the Ti content. However, when the Ti content increases, silica and titania phases in silica–titania mixed oxides can separate. This phase separation leads to the precipitation of the titania component as rutile or anatase crystals. When silica–titania mixed oxides undergo phase separation, their properties become unstable; for example, the refractive index of the particles becomes non-uniform. Therefore, it is preferable to synthesize silica–titania mixed oxides in an amorphous state without causing phase separation. Based on our previous studies on particle size control in silica synthesis, we employed a dry process using organosilicon compounds to synthesize silica–titania mixed oxides. In this study, spherical amorphous silica–titania mixed oxide particles were obtained via flame synthesis using organosilicon and organotitanium compounds. The purpose of this study was to characterize the obtained powder and explore the possibility of controlling particle size during synthesis. By studying the dry process synthesis of spherical silica–titania mixed oxide particles, we confirmed the relationships: between the Si/Ti molar ratio and the obtained crystal structure and between the adiabatic flame temperature and the particle size.  相似文献   
725.
Zwitterionic molecules, such as zwitterionic liquids (ZILs) and polypeptides (ZIPs), are attracting attention for application in new methods that can be used to loosen tight cell wall networks in a biocompatible manner. These novel methods can enhance the cell wall permeability of nanocarriers and increase their transfection efficiency into targeted subcellular organelles in plants. Herein, we provide an overview of the recent progress and future perspectives of such molecules that function as boosters for cell wall-penetrating nanocarriers.  相似文献   
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