Abstract: A system for pumping lubricant in a gas transportation pipeline includes a pipeline robot and a control terminal system. The pipeline robot includes a lubricant position detection, module, a lubricant pumping module, an electro-hydraulic control system, a data acquisition and processing system, and a lubricant sucking port. The location at which the lubricant deposits can be detected online, and the lubricant staving in the gas transportation pipeline can be removed in real time. The system is highly automatic and efficient. Resistance against the natural as transportation is reduced effectively, the efficiency of transporting the natural gas is improved, and safety of transporting the natural gas is ensured.

Abstract: The invention discloses a multi-stage quantization method, which includes the following steps: obtaining a reference codebook according to a previous stage codebook; obtaining a current stage codebook according to the reference codebook and a scaling factor; and quantizing an input vector by using the current stage codebook. The invention also discloses a multi-stage quantization device. With the invention, the current stage codebook may be obtained according to the previous stage codebook, by using the correlation between the current stage codebook and the previous stage codebook. As a result, it does not require an independent codebook space for the current stage codebook, which saves the storage space and improves the resource usage efficiency.