Abstract: The present disclosure discloses a time service and positioning network system for an underground chain-shaped large space in a coal mine. The system adopts a base station-level network internal time synchronization method which takes an optical fiber time service as a main part and takes a satellite time service as an auxiliary part to construct a time service and positioning network system with an unified time within the ad-hoc network base stations, based on the ad-hoc network base stations linearly arranged in the underground chain-shaped large space in the coal mine. Through the network construction, the network stabilization and the network application, the system unifies the time reference of the base station-level network and improves the positioning accuracy of the network application by utilization of the base station-level network internal time synchronization method.

Abstract: The present disclosure discloses a time service and positioning network system for an underground chain-shaped large space in a coal mine. The system adopts a base station-level network internal time synchronization method which takes an optical fiber time service as a main part and takes a satellite time service as an auxiliary part to construct a time service and positioning network system with an unified time within the ad-hoc network base stations, based on the ad-hoc network base stations linearly arranged in the underground chain-shaped large space in the coal mine. Through the network construction, the network stabilization and the network application, the system unifies the time reference of the base station-level network and improves the positioning accuracy of the network application by utilization of the base station-level network internal time synchronization method.

Abstract: The present disclosure discloses a low-energy-consumption grading and positioning method and system for a coal mine auxiliary transportation vehicle, which belongs to the technical field of mine tunnel transportation.

Abstract: The present disclosure discloses a low-energy-consumption grading and positioning method and system for a coal mine auxiliary transportation vehicle, which belongs to the technical field of mine tunnel transportation.

Abstract: The disclosure provides techniques for storage device input/output (I/O) performance improvement in a remote computing environment. Embodiments include creating, on a remote device that is remote from a client device, a virtual storage device corresponding to a physical storage device that is located on the client device. Embodiments include receiving, by a driver on the remote device, a request from an application on the remote device to perform an input or output operation with respect to the virtual storage device. Embodiments include sending, by the remote device, a block-level input or output operation to the client device based on the request. Embodiments include receiving, by the remote device, a result of the block-level input or output operation from the client device. Embodiments include providing, by the driver on the remote device, to the application, a response to the request based on the result of the block-level input or output operation.

Abstract: A method and an apparatus for satellite laser broadband demodulation are provided. The method includes: setting a residual carrier to a carrier acquisition range of a receiver, pulling the residual carrier to an MHz level by adjusting a frequency of a local oscillator laser, and obtaining a precise carrier frequency according to an accurate frequency acquisition, such that the residual carrier enters a fast acquisition band of a carrier tracking phase-locked loop. After carrier acquisition is achieved, carrier tracking and data recovery processing are performed. According to the present disclosure, signal equalization of an ultra-high bandwidth/ultra-high bit rate can be implemented, and carrier acquisition, tracking, and demodulation are quickly achieved for a modulation signal in a high dynamic range.