Abstract: The present disclosure relates to methods, apparatuses, and computer readable medium for communication in a passive optical network. According to an embodiment, a method for communication implemented at an optical network unit may includes receiving an optical network unit management and control interface (OMCI) message from an optical line terminal, the OMCI message including configuration information on a synchronization status message incoming (SSM-IN) managed entity; receiving synchronization status information from the optical line terminal; and processing the received synchronization status information according to the configuration of the SSM-IN managed entity.

Abstract: Embodiments of the present disclosure relate to methods, optical line terminals (OLTs), optical network units (ONUs), apparatuses and computer storage media for transmitting a time synchronization message. In some example embodiments, the OLT is configured to: determine a threshold rate to be N messages per second for transmission of a time synchronization message to an ONU, wherein N being greater than or equal to 0.1; and transmit, to the ONU, a time synchronization message at the threshold rate or a rate above the threshold rate, to enable the ONU to perform time synchronization with the OLT. In some other example embodiments, the OLT is configured to: select a plurality of ONUs for transmitting time synchronization information; and transmit, to the ONUs, a broadcast or multicast message the time synchronization information, to enable the plurality of ONUs to perform time synchronization with the OLT.

Abstract: A method for channel management in an optical network unit includes receiving a disable channel action message sent by an optical line terminal, wherein the disable channel action message is used to instruct disabling a first channel of the optical network unit; transferring the state machine of the optical network unit on the first channel from the association substate of the operation state to the pending substate according to the disable channel action message; and turning off the transmitter and/or the receiver on the first channel after a specified time is reached, transferring the state machine from the pending substate of the operation state to the disabling channel status, and starting a timer.

Abstract: A method for channel management in an optical network unit includes receiving a disable channel action message sent by an optical line terminal, wherein the disable channel action message is used to instruct disabling a first channel of the optical network unit; transferring the state machine of the optical network unit on the first channel from the association substate of the operation state to the pending substate according to the disable channel action message; and turning off the transmitter and/or the receiver on the first channel after a specified time is reached, transferring the state machine from the pending substate of the operation state to the disabling channel status, and starting a timer.

Abstract: Embodiments of the present disclosure relate to methods, optical line terminals (OLTs), optical network units (ONUs), apparatuses and computer storage media for transmitting a time synchronization message. In some example embodiments, the OLT is configured to: determine a threshold rate to be N messages per second for transmission of a time synchronization message to an ONU, wherein N being greater than or equal to 0.1; and transmit, to the ONU, a time synchronization message at the threshold rate or a rate above the threshold rate, to enable the ONU to perform time synchronization with the OLT. In some other example embodiments, the OLT is configured to: select a plurality of ONUs for transmitting time synchronization information; and transmit, to the ONUs, a broadcast or multicast message comprising the time synchronization information, to enable the plurality of ONUs to perform time synchronization with the OLT.

Abstract: The invention that relates to the field of hydropower scheduling presents a method for long-tens optimal operations of interprovincial hydropower system considering peak-shaving demands. It can take full advantage of the differences of hydrological characteristics among hydropower plants on different rivers to implement compensation operations of interprovincial hydropower system. In this operation, typical daily load demands during dry season are considered to optimize the allocation of hydropower production over one year. The purpose is to increase the dispatchable generation capacity for peak demands of power grids. The technology scheme of the invention can be summarized as follows. A multi-objective model of hydropower system operations is established with maximizing generation production and minimizing the difference rate between peak and valley load during dry period.

Abstract: The invention that relates to the field of hydropower scheduling presents a method for long-term optimal operations of interprovincial hydropower system considering peak-shaving demands. It can take full advantage of the differences of hydrological characteristics among hydropower plants on different rivers to implement compensation operations of interprovincial hydropower system. In this operation, typical daily load demands during dry season are considered to optimize the allocation of hydropower production over one year. The purpose is to increase the dispatchable generation capacity for peak demands of power grids. The technology scheme of the invention can be summarized as follows. A multi-objective model of hydropower system operations is established with maximizing generation production and minimizing the difference rate between peak and valley load during dry period.