The invention provides a time synchronization method and device, and relates to the technical field of communication. The method comprises the following steps: sending a first time synchronization instruction to each reference AP, wherein the first time synchronization instruction is used for indicating the reference AP to send a second time synchronization instruction to each member AP included in a sub-network where the reference AP is located; receiving a sending timestamp and a first receiving timestamp of each member AP returning a second time synchronization instruction in each sub-network; according to the network attribution relation of the edge APs, the sending timestamp and the first receiving timestamp, determining time adjustment information of the first type of APs, wherein the first type of APs are APs with to-be-adjusted time; and according to the time adjustment information, sending a third time synchronization instruction to the first type of AP, and indicating the first type of AP to execute a time synchronization operation. According to the method, on the premise that the overall cost of equipment is not increased, time synchronization within a large-scale wholenetwork range is achieved, and the problems that an existing method is high in complexity and high in cost are solved.

Time synchronization method and device

The invention discloses a time synchronization method and device and a network system, and the method comprises the steps: determining whether a local clock is a master clock or a slave clock according to a configured clock priority; When the clock is a master clock, writing the local clock as the master clock into a synchronization frame at predetermined intervals, and broadcasting and sending the synchronization frame; Or when the clock is a slave clock, receiving a synchronization frame; And synchronizing a local clock according to the synchronization frame. By adopting the scheme providedby the invention, accurate time synchronization among the devices in the system can be realized.

Time synchronization method, device and network system

The invention provides a multi-machine synchronization method for a BMS simulation system, and the method comprises the steps: randomly specifying one gateway from all gateways as a main gateway, andcarrying out the clock synchronization of the main gateway through employing an upper computer; after the main gateway completes clock synchronization, carrying out clock synchronization on other gateways through the main gateway; and when the gateway sends an upper computer data packet to the simulation test module, achieving clock synchronization of the simulation test module by adding a timestamp to the upper computer data packet. The method has the advantages that the accuracy of time synchronization among multiple gateways can be improved, the synchronization efficiency is improved, and the resource consumption is reduced.

Multi-machine synchronization method for BMS simulation system

The embodiment of the invention discloses an intelligent cabinet monitor, and the monitor collects the current information of all monitoring targets of an intelligent cabinet and the detection data ofall sensors, and uploads the current information and the detection data to a cloud server. The intelligent cabinet provided by the embodiment of the invention adopts the monitor, so that the intelligent cabinet can be monitored more comprehensively and effectively, the operation and maintenance efficiency can be improved, and the operation and maintenance cost can be reduced.

Intelligent cabinet and monitor thereof

The invention relates to the technical field of computer input equipment, in particular to a scanner with an image processing function. The scanner comprises a body, a platen, a scanning mechanism anda control circuit. The body is used for mounting the scanning mechanism, the direction conversion system and the control circuit. The manuscript table is used for placing manuscripts. The scanning mechanism is used for scanning manuscripts placed on the manuscript table. The control circuit is used for controlling the scanning mechanism to scan the document and perform image processing on a scanned image. The scanner is a flat plate type scanner or a paper feeding automatic scanner. The image processing function is set in the control circuit of the scanner, the scanned image is processed in the scanner, the data transmission amount is reduced, and the transmission time is shortened. Meanwhile, data loss is avoided, and the scanner has the advantages of improving the office efficiency andimproving the data integrity.

Scanner with image processing function

The invention relates to a distributed network clock synchronization method. The distributed network clock synchronization method is applied to a distributed network, and comprises the steps of: determining a master device and a slave device through a clock selection algorithm; measuring the link delay of the master device and the slave device; obtaining the time difference of the master device and the slave device through the link delay; and completing clock synchronization of the slave device through the master device and the time difference. According to the embodiment of the invention, thelink delay is measured; furthermore, the time difference is calculated through the link delay; then, clock synchronization is realized; therefore, the clock synchronization precision of the distributed network is up to the nanosecond level; furthermore, the distributed network has relatively high stability; namely, when the equipment in the distributed network is abnormal, the distributed networkcan adaptively adjust the network structure within a short time; a proper master clock is re-selected; and furthermore, clock synchronization is completed.

Distributed network clock synchronization method

The invention relates to a distributed network clock synchronization system. The system comprises a clock source for sending clock synchronization information; and at least one level of slave equipment progressively connected to the clock source and used for progressively receiving the clock synchronization information and accomplishing the clock synchronization, wherein the clock source and the at least one level of slave equipment are nodes in the distributed network clock synchronization system. Through the system disclosed by the embodiment of the invention, the link delay is measured, thetime difference is computed through the link delay, and then the clock synchronization is realized, so that the clock synchronization precision of the distributed network clock synchronization systemcan achieve nanosecond level; and the system has strong stability; when the equipment in the distributed network is abnormal, the distributed network can self-adaptively adjust the network structurein the short time, and the appropriate main clock is reselected to accomplish the clock synchronization.

Distributed network clock synchronization system

The invention discloses a road administration cabinet intelligent monitoring system based on the internet of things. The system comprises a cabinet safety monitoring module, a cabinet asset managementmodule, an inspection operation and maintenance management module and a management server module; equipment safety monitoring module, equipment asset management module and the inspection operation and maintenance management module are all connected with the management server module; the cabinet safety monitoring module is used for detecting cabinet operation information and sending the cabinet operation information to the management server module; the cabinet asset management module is used for managing equipment installation registration information in a cabinet and sending the installationregistration information to the management server module; the inspection operation and maintenance management module is used for recording maintenance personnel information and sending the maintenancepersonnel information to the management server module; and the management server module is used for displaying at least one type of the cabinet operation information, the installation registration information and the maintenance personnel information.

Road administration cabinet intelligent monitoring system based on the internet of things

The utility model relates to an image processing device for portable scanner, include the casing, set up at the LCD of casing upper surface display screen and set up at the inside image processing circuit board of casing, wherein, seted up external connection port on the lateral wall of casing, the integration has power module, FPGA module, LCD drive module, SDRAM module, STM32 processing module and wiFi module on the image processing circuit board, the FPGA module is connected to external connection port, SDRAM module and STM32 processing module respectively, STM32 processing module is connected to wiFi module and LCD drive module. The utility model discloses an image processing device is applicable to image acquisition device and the portable scanner that the image processing device separates, makes things convenient for the image effect and the quality of in situ observation scanning to to operations such as scan imagery enlarge, reduces, compares.

A image processing device for portable scanner

The invention relates to a scanning method based on a portable scanner. The portable scanner is provided with an optical acquisition front-end and a data processing rear-end connected through a shielded wire. The method comprises the steps that: the optical acquisition front-end and the data processing rear-end are started; the optical acquisition front-end moves in an area to be scanned to obtainimage information, and sends the image information to the data processing rear-end through the shielded wire; and the data processing rear-end receives the image information, and processes the imageinformation. According to the scanning method based on the portable scanner disclosed by the invention, the optical acquisition front-end performs image acquisition; the data processing rear-end performs image processing and checking; an optical assembly and a CIS sensor are separately integrated in the optical acquisition front-end, which is compact in volume; therefore, image scanning in a narrow space can be conveniently carried out; and effective image acquisition in different complex scenes can be ensured.

Lyu Ning

Papers

Distributed network clock synchronization method

Distributed network clock synchronization system

Road administration cabinet intelligent monitoring system based on the internet of things

A image processing device for portable scanner

Scanning method based on portable scanner