This study presents an analysis of the relationship of angles and trigonometric functions by applying Hall Effect Sensor (HES). Electromagnetic density of 4.624 mT can be generated from the Helmholtz coil. Angle of sh...This study presents an analysis of the relationship of angles and trigonometric functions by applying Hall Effect Sensor (HES). Electromagnetic density of 4.624 mT can be generated from the Helmholtz coil. Angle of shaft which was installed at the center of the Helmholtz coil perpendicularly to horizontal plane was considered as reference and can be rotated. In this study, an experiment for measuring the angle of shaft declination on X-axis was carried on. Ranges of measurement were related to the angle resolution between –15 to 15 degree with 1 step degree interval from perpendicular angle (Y-axis). Analysis of the relationship between shaft declination and electromagnetic field was performed using HES device which was installed on the top of shaft and perpendicularly to reference electromagnetic field [1,2]. The angle declining from the origin which was normal to magnetic field can be determined by measuring the relationship between Hall voltage and magnetic field. Normally, electromagnetic field is nonuniform and varied by point in Helmholtz coil radius. Shaft angles on X-axis were measured for assessing the repeatability of system developed. Five values of results were measured repeatedly at the same input. It can be observed that the system developed can provide the results with the best accuracy and reliability of 95%.展开更多
Using the moment tensor inversion method, we calculate the focal mechanisms of the aftershock sequence of the Ms=6.1 Lulong earthquake occurred on October 19, 1982 in Hebei Province. We found that the pressure axis in...Using the moment tensor inversion method, we calculate the focal mechanisms of the aftershock sequence of the Ms=6.1 Lulong earthquake occurred on October 19, 1982 in Hebei Province. We found that the pressure axis in Lulong basin is nearly in the east-west direction with an azimuth of N74°E. However, in the north of the basin the stress axis changes to N43°E; and in some places near the center of the basin it changes to the northwest that is almost perpendicular to the P axis obtained by us from those events around the basin. This feature illuminates that in Lulong earthquake sequence, the stress direction is different in different parts of crustal structure, which shows that the tectonic movement in Lulong region is complex. This is because that Lulong is located in the eastern part of Chinese mainland and is subject to the compression of Japanese Sea Basin driven by the Pacific Plate. On the other hand, nipped by the Yanshan and North China blocks, Lulong is obviously restricted by the block boundaries.展开更多
文摘This study presents an analysis of the relationship of angles and trigonometric functions by applying Hall Effect Sensor (HES). Electromagnetic density of 4.624 mT can be generated from the Helmholtz coil. Angle of shaft which was installed at the center of the Helmholtz coil perpendicularly to horizontal plane was considered as reference and can be rotated. In this study, an experiment for measuring the angle of shaft declination on X-axis was carried on. Ranges of measurement were related to the angle resolution between –15 to 15 degree with 1 step degree interval from perpendicular angle (Y-axis). Analysis of the relationship between shaft declination and electromagnetic field was performed using HES device which was installed on the top of shaft and perpendicularly to reference electromagnetic field [1,2]. The angle declining from the origin which was normal to magnetic field can be determined by measuring the relationship between Hall voltage and magnetic field. Normally, electromagnetic field is nonuniform and varied by point in Helmholtz coil radius. Shaft angles on X-axis were measured for assessing the repeatability of system developed. Five values of results were measured repeatedly at the same input. It can be observed that the system developed can provide the results with the best accuracy and reliability of 95%.
基金National Natural Science Foundation of China(40234038)
文摘Using the moment tensor inversion method, we calculate the focal mechanisms of the aftershock sequence of the Ms=6.1 Lulong earthquake occurred on October 19, 1982 in Hebei Province. We found that the pressure axis in Lulong basin is nearly in the east-west direction with an azimuth of N74°E. However, in the north of the basin the stress axis changes to N43°E; and in some places near the center of the basin it changes to the northwest that is almost perpendicular to the P axis obtained by us from those events around the basin. This feature illuminates that in Lulong earthquake sequence, the stress direction is different in different parts of crustal structure, which shows that the tectonic movement in Lulong region is complex. This is because that Lulong is located in the eastern part of Chinese mainland and is subject to the compression of Japanese Sea Basin driven by the Pacific Plate. On the other hand, nipped by the Yanshan and North China blocks, Lulong is obviously restricted by the block boundaries.
