At present, hole trajectory azimuth Angle is measured mainly with magnetism sensor, but which is restricted by magnetic field and the metal tube around the surveying equipment.

目前的井眼轨迹方位角测量技术主要靠磁通门传感器，这种技术受地磁场及测量体周围金属管体的制约。

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Magnetism of permanent magnet affects the accuracy of electromagnetic force balance sensor, and is important to compensate the effects of the magnetism.

永磁体磁性能的稳定性直接影响电磁力平衡传感器的精度，其自动补偿具有重要意义。

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The control equipment includes centralized control device for set, AC field system of exciter, device for assisting magnetism (DAM), speed sensor of generator, and braking controller for blower fan.

控制装置设有机组集控装置、励磁机交流励磁装置、发电机助磁装 置、发电机转速传感器和风机制动控制器；

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As a material highly sensitive to the environment, graphene could act as a sensor with a single device measuring strain, gas, magnetism or pressure.

BBC: Is graphene really a wonder-material?