Abstract: Implementations described herein relate to methods, devices, and computer-readable media to transcode a video. In some implementations, a computer-implemented method includes obtaining a video that includes a plurality of tracks. The method further includes determining whether a partial transcoded file is available that corresponds to the video. The method further includes, if the partial transcoded file is available, obtaining a timestamp associated with the partial transcoded file, transcoding a portion of the video that begins at the timestamp associated with the partial transcoded file, and combining the partial transcoded file and the transcoded portion of the video to generate an output video. The method further includes, if the partial transcoded file is not available, transcoding the video from a start of the video using the transcoder to obtain a plurality of output tracks and combining the plurality of output tracks to obtain the output video.

Abstract: A method and device for timing in time-varying distance protection based on multiple lines of a tower. The method includes: collecting an instantaneous current value at a time-varying distance protection installation location in the multiple lines of the tower, and acquiring preset parameters; calculating, according to the preset parameters and a multi-line ranging model, a multi-line ranging result; calculating, according to the preset parameters, the multi-line ranging result, and an adaptive calculation model, time of a section-II distance protection action and final time of a section-III distance protection action; and determining, according to the instantaneous current value, the preset parameters, and a cross-line failure auxiliary criterion model, final time of the section-II distance protection action.

Abstract: A line double-end steady-state quantity distance measuring method and system based on an amplitude-comparison principle. According to the method and system, voltage values and current values of both sides of a line before and after a fault are collected (102), a voltage variable quantity and a current variable quantity of both sides of the line are calculated (103), and after a voltage phasor value and a current phasor value are determined according to the voltage variable quantity and the current variable quantity (104), the position of a short-circuit point is determined by performing iterative calculation on the voltage of the short-circuit point. The method is simple in principle, and can accurately recognize a fault point, achieving precise distance measurement of lines.

Abstract: A method and device for timing in time-varying distance protection based on multiple lines of a tower. The method includes: collecting an instantaneous current value at a time-varying distance protection installation location in the multiple lines of the tower, and acquiring preset parameters; calculating, according to the preset parameters and a multi-line ranging model, a multi-line ranging result; calculating, according to the preset parameters, the multi-line ranging result, and an adaptive calculation model, time of a section-II distance protection action and final time of a section-III distance protection action; and determining, according to the instantaneous current value, the preset parameters, and a cross-line failure auxiliary criterion model, final time of the section-II distance protection action.

Abstract: Implementations described herein relate to methods, devices, and computer-readable media to transcode a video. In some implementations, a computer-implemented method includes obtaining a video that includes a plurality of tracks. The method further includes determining whether a partial transcoded file is available that corresponds to the video. The method further includes, if the partial transcoded file is available, obtaining a timestamp associated with the partial transcoded file, transcoding a portion of the video that begins at the timestamp associated with the partial transcoded file, and combining the partial transcoded file and the transcoded portion of the video to generate an output video. The method further includes, if the partial transcoded file is not available, transcoding the video from a start of the video using the transcoder to obtain a plurality of output tracks and combining the plurality of output tracks to obtain the output video.

Abstract: Implementations described herein relate to methods, devices, and computer-readable media to transcode a video. In some implementations, a computer-implemented method includes obtaining a video that includes a plurality of tracks. The method further includes determining whether a partial transcoded file is available that corresponds to the video. The method further includes, if the partial transcoded file is available, obtaining a timestamp associated with the partial transcoded file, transcoding a portion of the video that begins at the timestamp associated with the partial transcoded file, and combining the partial transcoded file and the transcoded portion of the video to generate an output video. The method further includes, if the partial transcoded file is not available, transcoding the video from a start of the video using the transcoder to obtain a plurality of output tracks and combining the plurality of output tracks to obtain the output video.

Abstract: Implementations described herein relate to methods, devices, and computer-readable media to transcode a video. In some implementations, a computer-implemented method includes obtaining a video that includes a plurality of tracks. The method further includes determining whether a partial transcoded file is available that corresponds to the video. The method further includes, if the partial transcoded file is available, obtaining a timestamp associated with the partial transcoded file, transcoding a portion of the video that begins at the timestamp associated with the partial transcoded file, and combining the partial transcoded file and the transcoded portion of the video to generate an output video. The method further includes, if the partial transcoded file is not available, transcoding the video from a start of the video using the transcoder to obtain a plurality of output tracks and combining the plurality of output tracks to obtain the output video.

Abstract: A current differential protection method for a self-adaptive half-wavelength line based on a time-difference method. Since an electrical distance of half-wavelength power transmission is long, after a fault occurs, there is an obvious time difference between the actuation times for protecting starting elements at two sides of a line. According to the principles of wave propagation, the position of a fault point can be determined by means of a difference between the actuation times for protecting the starting elements at the two sides of the line. By means of taking the fault point as a differential point, a current value at the differential point can be obtained according to a long line equation by means of the voltage and current at protection-mounted positions at the two sides of the line, and a differential current is then calculated.

Abstract: A method of free wave energy protection for a half-wavelength line based on a one-sided current includes: performing sampling and calculation on a current at protection measuring points to obtain variations in current sampling values; and activating a protective element to determine an occurrence time of a fault in a half-wavelength line. A free wave energy protection section includes a quick-action section, a basic section and a sensitive section, wherein the quick-action section, the basic section and the sensitive section serve as action criteria for performing protection with respect to the free wave energy of the half-wavelength line.

Abstract: A concomitant impedance protection method for a half-wavelength power transmission line includes that: three-phase currents and three-phase voltages of a relay protection device mounting position at an M side and a relay protection device mounting position at an N side of the half-wavelength power transmission line are acquired respectively; it is judged whether starting amounts of an M side and an N side meet starting conditions or not; a failure point F is determined according to a time difference when the starting amounts of the M side and the N side meet the starting conditions; and a relay protection action of the half-wavelength power transmission line is started according to concomitant impedance of the half-wavelength power transmission line.

Abstract: A method of free wave energy protection for a half-wavelength line based on a one-sided current includes: performing sampling and calculation on a current at protection measuring points to obtain variations in current sampling values; and activating a protective element to determine an occurrence time of a fault in a half-wavelength line. A free wave energy protection section includes a quick-action section, a basic section and a sensitive section, wherein the quick-action section, the basic section and the sensitive section serve as action criteria for performing protection with respect to the free wave energy of the half-wavelength line.

Abstract: A current differential protection method for a self-adaptive half-wavelength line based on a time-difference method. Since an electrical distance of half-wavelength power transmission is long, after a fault occurs, there is an obvious time difference between the actuation times for protecting starting elements at two sides of a line. According to the principles of wave propagation, the position of a fault point can be determined by means of a difference between the actuation times for protecting the starting elements at the two sides of the line. By means of taking the fault point as a differential point, a current value at the differential point can be obtained according to a long line equation by means of the voltage and current at protection-mounted positions at the two sides of the line, and a differential current is then calculated.

Abstract: A concomitant impedance protection method for a half-wavelength power transmission line includes that: three-phase currents and three-phase voltages of a relay protection device mounting position at an M side and a relay protection device mounting position at an N side of the half-wavelength power transmission line are acquired respectively; it is judged whether starting amounts of an M side and an N side meet starting conditions or not; a failure point F is determined according to a time difference when the starting amounts of the M side and the N side meet the starting conditions; and a relay protection action of the half-wavelength power transmission line is started according to concomitant impedance of the half-wavelength power transmission line.