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Many wooden Chinese historic buildings are destroyed due to the ravages of frequent fire disasters. The fire risk of historic buildings are highly enlarged since a long-time weathered wooden structures in the natural environment. The clean fire-extinguishing technology using fluorinated chemical gases to put out a historic building fire rapidly at the initial stage is highly recommended and widely used. However, the gaseous hydrogen fluoride (HF) yielded during the fire suppression process could be a potential method to result in secondary damage due to its corrosiveness. Nowadays, experiments were employed to clarify the effect of fire suppression on the surface of historic wooden buildings. Five traditional fluorinated chemical gases, H-37, FK-5-1-12, H-1323, H-2402, and H-1301, are used to suppress a fixed flame. The wooden samples, including a Dao Talisman board, a painting paper, and wooden chips, are placed in a chamber. Wooden chips consist of traditional and weathered samples (acting as the Chinese historic buildings). The concentration of gaseous products yielded from fire suppression are monitored by a gas-FTIR from ABB, and the surface analysis is conducted by a Quanta FEG SEM–EDX from FEI. It is observed that flame enhancement happens at the early stage of fire suppression and varies with fire agents. The amount of F-deposited on the wooden surface is positively correlated with a total amount of gaseous HF. The color change mechanism of the wooden surface is comprehensive, although the amount of HF is a leading factor. The influence of HF on color change depends on the amount of both gaseous H2O and HF. It is concluded that the value of L* of the traditional chip is much easier to be reduced comparing with weathered samples with the same wood grain. The reduction of$${\mathrm{b}}^{*}$$b∗value of weathered samples is much larger than the traditional ones. It suggests the weathered chips show a color shift toward blue because of fire suppression. The present study hopes to provide a basic acknowledgment for the comprehensive understanding of secondary damage caused by fire suppression.

Sensor fusion is a key technology in ADAS (FCW, PCW, AEB, ACC, etc.) In this paper, the target-level fusion method is used to realize the recognition of key targets through the algorithms such as estimation of the driving area, screening for effective targets, targets matching, target fusion and target tracking. Simulation test and real vehicle test show that the algorithms can identify key targets steadily and screen out radar jamming targets such as guardrails and viaducts.

A low-cost and intelligent power supply system with an STC15 single-chip microcomputer as the main controller is designed. The single chip monitors the mains voltage and controls the relay to switch between the mains and battery power supply. Battery constant current, constant voltage, and floating charge intelligent charging management are achieved through the battery voltage execution. Through the ESP8266WIFI module networking, we can access weather information, and weather judgment, and choose whether to enter the battery mode, which can better protect the power system. The experimental results show that the system can operate reliably and complete the switch between mains supply mode and battery supply mode quickly.

With the continuous development of new energy technology, the photovoltaic system plays an extremely important role in people’s production and life, and new energy. As an indispensable part of a photovoltaic system, the battery voltage monitoring circuit plays a very important role. The voltage of the photovoltaic battery pack is usually relatively high. To ensure the safety of users and ensure that the controller is not affected by other adverse factors, this paper designs a voltage sampling circuit based on a high-precision linear optocoupler HCNR201. The detection circuit has strong electrical isolation characteristics and can monitor the voltage of two or more battery groups. In this paper, two groups of battery voltage monitoring using simulation and hardware test results proved that the voltage detection method has good linearity, and high accuracy, while the input and output of electrical isolation ensure user safety.