http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Research on Transferring the National Height System to the Island
Yanxiong LIU,Xinghua ZHOU,Lin PENG,Yongtong WU 한국항해항만학회 2006 한국항해항만학회 학술대회논문집 Vol.1 No.-
It is quite difficult to transfer the National Height System 1985 to the island in China. In the study, one feasible and alternative way, which measures synchronally the tide variation at the island and the coast , is firstly introduced. Then, a new method is proposed. This new method combines GPS technique and Quasi-Geoid Determination technique (GQGD). It needs gravity data, GPS data, leveling data and DEM data, together with complex calculation method and the Earth gravity model. After describing the mathematical model and presenting the calculational steps, one experiment has been shown that this method is valid and can achieve accuracy up to 5 cm for the normal height, compared with the results both from the tidal observation and height approximation. Some suggestion is also given in the end.
Research on the effect of ultrasonic vibration on the roll-over during the fine blanking process
Yanxiong Liu,Tao Cheng,Lin Hua,Huajie Mao 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.2
Fine blanking process as an advanced sheet metal cutting process has been widely used in industry. However, the roll-over of the parts fabricated by this process weakens the performance. For some parts, i.e. gear, the size of the roll-over should be very small in some situation. Therefore, a lot of efforts have been made to reduce the roll-over size or even eliminate the roll-over. Since the high frequency vibration can greatly change the metal flow, the ultrasonic vibration was applied into the fine blanking process to eliminate the roll-over in this paper. A finite element model was created to investigate the roll-over forming mechanism in the ultrasonic vibration assisted fine blanking process. The forming force, metal flow and mean stress were analyzed and compared with the conventional fine blanking process, and the roll-over size variation mechanism of the ultrasonic vibration assisted fine blanking process was revealed. An experiment of ultrasonic vibration assisted fine blanking has been carried out in this paper, and the roll-over size variation during the conventional and ultrasonic vibration assisted fine blanking process were compared. The results show that the experiment result has a good agreement with that of the finite element simulation. From this research, it can get that the ultrasonic vibration can greatly reduce the roll-over size, and it has a promising future to be used in the fine blanking process.
Wuhao Zhuang,Lin Hua,Xiaowen Wang,Yanxiong Liu,Liying Dong,Heping Dai 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.2
Roll-forging process is widely used to fabricate the automobile front axle beams. The reasonable selection of the process parameters is significant to ensure the quality and improve the property of the automobile front axle beam owing to the complexity and importance of the preliminary roll-forging process. This paper developed a 3D Finite element (FE) model of the preliminary roll-forging process of the AISI-1045 automobile front axle beam under the Deform-3D platform. A corresponding experiment is subsequently conducted. Good agreement between the experimental and simulative results validates the employed model. Based on this dependable FE model, the influences of initial temperature of billet T 0 , rotational speed of rolls n and friction factor m on the geometric dimension, temperature inhomogeneity, deformation inhomogeneity, and roll-forging load are investigated comprehensively. The results can provide reliable guidelines for the selection of process parameters.