Abstract: The disclosure provides a broadcast-type underwater navigation positioning system and method, wherein the system comprises a base station network consisting of a plurality of underwater base stations distributed on a seabed and a to-be-positioned user terminal located underwater, wherein the underwater base station comprises a bottom-mounted sonar and an mooring sonar, the bottom-mounted sonar and the mooring sonar are connected through a cable and are configured for ranging and communication through an underwater acoustic signal, the mooring sonar is integrated with an inertial measurement unit I, and the user terminal is provided with a passive sonar configured to unidirectionally receive an underwater acoustic signal sent by the mooring sonar for ranging and communication.

Abstract: A new GNSS-based real-time high-precision wave measurement method, wherein the GNSS phase, pseudo-range, Doppler frequency shift observations and broadcast ephemerides are collected by a GNSS receiver, and antenna carried by a sea surface carrier; the three-dimensional speeds of a carrier are acquired using an epoch difference of phase observations; and wave element information are then solved. The wave element information can also be obtained by integrating the speeds for a certain duration and removing a linear trend term to obtain a time-dependent displacement variations. No additional precise differential correction is needed, thereby saving on service costs and communication costs of precise differential corrections. High-precision wave element information is obtained in real time, and locally stored in a buoy or periodically returned by communication, thereby expanding the working range of GNSS-based ocean wave measurement.

Abstract: An ultrasound-assisting quenching process includes: S1) connect the workpiece with the ultrasonic unit tightly; S2) heat the workpiece to the quenching temperature and then hold for a period of time; S3) start the ultrasonic unit, then the ultrasound energy can be injected into the workpiece directly; and S4) put the workpiece into the coolant quickly to make the workpiece to be quenched. The device for this process mainly includes the ultrasonic unit and a heating unit. This invention inputs the ultrasound energy into the workpiece during the quenching process. Under the action of the ultrasound, the grain size of the workpiece after quenching process will be much smaller compared with the conventional quenching process. Therefore, the ultrasound-assisting quenching process can improve the strength and plasticity of the material, and extend the life of the workpiece.

Abstract: The method according to embodiments of the present invention includes: allocating, by a management platform, a first multipoint control server to a first conference according to conference information of the first conference carried in a call from any site, where the conference information of the first conference includes a conference access number of the first conference and a site number included in the first conference, and the site number included in the first conference includes a conference access number of a second conference; and allocating, by the management platform, a second multipoint control server to the second conference according to conference information of the second conference carried in a call from the first multipoint control server, and establishing a cascading channel between the first multipoint control server and the second multipoint control server.

Abstract: An ultrasound-assisting quenching process includes: S1) connect the workpiece with the ultrasonic unit tightly; S2) heat the workpiece to the quenching temperature and then hold for a period of time; S3) start the ultrasonic unit, then the ultrasound energy can be injected into the workpiece directly; and S4) put the workpiece into the coolant quickly to make the workpiece to be quenched. The device for this process mainly includes the ultrasonic unit and a heating unit. This invention inputs the ultrasound energy into the workpiece during the quenching process. Under the action of the ultrasound, the grain size of the workpiece after quenching process will be much smaller compared with the conventional quenching process. Therefore, the ultrasound-assisting quenching process can improve the strength and plasticity of the material, and extend the life of the workpiece.

Abstract: The method according to embodiments of the present invention includes: allocating, by a management platform, a first multipoint control server to a first conference according to conference information of the first conference carried in a call from any site, where the conference information of the first conference includes a conference access number of the first conference and a site number included in the first conference, and the site number included in the first conference includes a conference access number of a second conference; and allocating, by the management platform, a second multipoint control server to the second conference according to conference information of the second conference carried in a call from the first multipoint control server, and establishing a cascading channel between the first multipoint control server and the second multipoint control server.