Abstract: A dialkyl carbonate is prepared by reacting urea with an alkyl monohydric alcohol at 70° C. to 150° C. under normal pressure or reduced pressure. The reaction is conducted for 6 h to 30 h under stirring and reflux, with one or more of magnesium, calcium, aluminum, chromium, manganese, iron, cobalt, nickel, copper and zinc as a primary catalyst and one or more compounds including an electron-donating nitrogen, phosphonis, oxygen or sulfur atom as a catalyst promoter. The dialkyl carbonate is prepared under low reaction temperature and normal pressure or reduced pressure, with high selectivity and high yield. With simple operations, high safety and low cost for the process, the method has prominent industrial application prospects.

Abstract: Responsive to the number of stations exceeding a first threshold number, the transmitting stations are prioritized relative to the station based on a station type. Responsive to the number of stations exceeding a second threshold number, the transmitting stations are prioritized relative to the station based on a station RSSI value. The station is assigned to the run queue with an ATF token responsive to being prioritized within the first or second thresholds permitting transmission of the data packet for the station. The station is assigned to a wait queue responsive to being prioritized outside of the first or second threshold not permitting transmission of the data packet for the station.

Abstract: Responsive to the number of stations exceeding a first threshold number, the transmitting stations are prioritized relative to the station based on a station type. Responsive to the number of stations exceeding a second threshold number, the transmitting stations are prioritized relative to the station based on a station RSSI value. The station is assigned to the run queue with an ATF token responsive to being prioritized within the first or second thresholds permitting transmission of the data packet for the station. The station is assigned to a wait queue responsive to being prioritized outside of the first or second threshold not permitting transmission of the data packet for the station.

Abstract: Provided are a network operation support system and a network device management method, belonging to the technical field of communications. The system uses a micro-service architecture realized based on a container, and the system itself has a good expansibility and availability, and supports automation and layout in a cloud environment. In addition, the system also uses a main database to synchronously store operating data of various micro-services for unified maintenance of the data, thereby improving the analysis efficiency of the system.

Abstract: A dialkyl carbonate is prepared by reacting urea with an alkyl monohydric alcohol at 70° C. to 150° C. under normal pressure or reduced pressure. The reaction is conducted for 6 h to 30 h under stirring and reflux, with one or more of magnesium, calcium, aluminum, chromium, manganese, iron, cobalt, nickel, copper and zinc as a primary catalyst and one or more compounds including an electron-donating nitrogen, phosphonis, oxygen or sulfur atom as a catalyst promoter. The dialkyl carbonate is prepared under low reaction temperature and normal pressure or reduced pressure, with high selectivity and high yield. With simple operations, high safety and low cost for the process, the method has prominent industrial application prospects.

Abstract: Provided are a network operation support system and a network device management method, belonging to the technical field of communications. The system uses a micro-service architecture realized based on a container, and the system itself has a good expansibility and availability, and supports automation and layout in a cloud environment. In addition, the system also uses a main database to synchronously store operating data of various micro-services for unified maintenance of the data, thereby improving the analysis efficiency of the system.

Abstract: The present invention provides a method, device and system for maintaining wireless networks, wherein the method includes: an AC receives a wireless access network status parameter fedback by an AP according to a time triggering mode or an event triggering mode; the AC updates the Status Set parameter of the AP locally stored, according to the wireless access network status parameter; the AC updates an event occurrence status parameter of the AP locally stored, according to the updated Status Set parameter and the event update strategy locally stored, wherein the event update strategy refers to an corresponding relationship between the Status Set parameter and the event occurrence status parameter; and the AC maintains the wireless network configuration parameter of the AP according to the updated event occurrence status parameter.

Abstract: The present invention relates to the field of communication technology, and particularly to a data distribution method, a data distribution device and a heterogeneous network. The data distribution method comprises: obtaining, via a data distribution device, cellular network access information and wireless local area network access identification information of a user terminal; obtaining, via the data distribution device, cellular network status information and wireless local area network status information; and judging, in combination of the obtained information and distribution policy, that downlink service is required to be distributed to a wireless local area network by the data distribution device, and guiding a data package in the downlink service needed to be distributed, to be distributed to the wireless local area network and transmitted to the user terminal.

Abstract: The present invention relates to the field of communication technology, and particularly to a data distribution method, a data distribution device and a heterogeneous network. The data distribution method comprises: obtaining, via a data distribution device, cellular network access information and wireless local area network access identification information of a user terminal; obtaining, via the data distribution device, cellular network status information and wireless local area network status information; and judging, in combination of the obtained information and distribution policy, that downlink service is required to be distributed to a wireless local area network by the data distribution device, and guiding a data package in the downlink service needed to be distributed, to be distributed to the wireless local area network and transmitted to the user terminal.

Abstract: In a distributed data transmission method, through acquiring the IP address of a user terminal in a first network and a physical address of the user terminal in a second network access module, according to the acquired addresses, when downlink service of the user terminal is distributed from the first network to the second network, an IP message whose destination address is the IP address of the user terminal in the first network is encapsulated to a message in a format corresponding to the medium access layer of the second network and afterwards is transmitted to the user terminal through the second network, and since the IP address bound to the user application is not changed, it is able to achieve seamless switch of the downlink service from the first network to the second network, avoiding problems of unnecessary interruption and restart of the user application and improving user experiences.

Abstract: This invention provides an access point and a system constructed based on the access point and an access controller. The access point includes a judgment module configured to judge whether the access point loses connection with an access controller; a first acquisition module configured to acquire a pre-stored user information list when the access point loses connection with the access controller, the user information list including identity authentication status of online users connected to said access point; and a second acquisition module configured to acquire authenticated online users according to the identity authentication status in said user information list, so that said access point would continue to serve the authenticated online users. This invention can improve user experience.

Abstract: The present invention provides a method, device and system for maintaining wireless networks, wherein the method includes: an AC receives a wireless access network status parameter fedback by an AP according to a time triggering mode or an event triggering mode; the AC updates the Status Set parameter of the AP locally stored, according to the wireless access network status parameter; the AC updates an event occurrence status parameter of the AP locally stored, according to the updated Status Set parameter and the event update strategy locally stored, wherein the event update strategy refers to an corresponding relationship between the Status Set parameter and the event occurrence status parameter; and the AC maintains the wireless network configuration parameter of the AP according to the updated event occurrence status parameter.

Abstract: The invention relates to the field of communication, and particularly to a method and a system for an application (APP) to obtain a media access control (MAC) address of a terminal. The method comprises: sending a request of MAC address inquiry to an access network through a local terminal; receiving a response of MAC address inquiry returned from the access network through the local terminal, with the response of MAC address inquiry carrying MAC address information of the local terminal, the MAC address information obtained by the access network during communication between the local terminal and the access network.