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The Multipath Exploitation Radar (MER) target detection technology is primarily based on the Non-Line-Of-Sight (NLOS) multipath propagation characteristics of electromagnetic waves, such as reflection and diffraction on the surface of the medium, enabling the effective detection of targets hidden in the “visually” blind area, such as urban street corners and vehicle occlusion. Thus, the technology can be feasible for various applications, including urban combat and intelligent driving. Further, it has significant practical and research implications. This paper summarizes the domestic and foreign literature in this field since the beginning of the 21st century to keep abreast of developments in this field and predict future development trends. The literature review revealed that according to the different types of detection platforms, MER target detection technology primarily consists of multipath detection technologies based on air and ground platforms. Both these technologies have achieved certain produced research results of practical significance. For air platforms, the following aspects are discussed: feasibility verification, analysis of influencing factors, architectural environment perception, and NLOS target detection. Further, for ground platforms, these four aspects are covered: target detection and recognition, two-dimensional target positioning, three-dimensional target information acquisition, and new detection methods. Finally, the prospects of MER target detection technology are summarized, and the potential issues and challenges in the current practical application of this technology are highlighted. These results show that MER target detection technology is evolving toward diversification and intelligence.

In view of the difficult situation of fire prevention, control, disaster resistance and relief in complex ventilation networks, the laws of air flow disturbance, heat transfer and smoke flow diffusion in air flow field, temperature field and smoke flow concentration field are analyzed. According to the evolution law of smoke flow at different fire source locations, an emergency linkage regulation scheme of fire air and smoke flow that can simultaneously meet the requirements of smoke exhaust air volume and stope air volume is proposed. Taking Zhuanlongwan Coal Mine as an application case, the fire smoke emergency linkage control system of Zhuanlongwan Coal Mine was established. In order to analyze the effect of air control and smoke exhaust, combined with the actual tunnel and ventilation parameters, a three-dimensional visualization model of its complex ventilation network was built based on VENTSIM software. The VentFire module is used to simulate the wind and smoke spreading effect of the fire scene in different fire source locations. The smoke exhaust effect and air volume distribution before and after the emergency control scheme is adopted are analyzed. The results show that when a fire occurs in different locations, the emergency smoke exhaust scheme should be started in time. On the basis of meeting the smoke exhaust air volume, the air volume of other key locations can still ensure more than 90% of the normal ventilation period, which can meet the disaster control and relief needs during the disaster of Zhuanlongwan Coal Mine.

In order to study the influence of low gas content and high gas pressure of the occurrence of the lower 5# coal seam of Yushuling Coal Mine in Xinjiang on the sensitivity of coal seam drillings gas desorption index, this paper adopted a constant temperature gas release test and low-temperature liquid nitrogen adsorption method to determine the gas adsorption law and pore composition of the coal samples of the lower 5# coal seam of Yushuling and the coal sample of Duanshi No.3 coal seam, to summarize and analyze the influence of pore structure characteristics and gas desorption rate of coal samples with different degrees of metamorphism on the accuracy of drillings desorption index. The results show that: the degree of coal metamorphism and pore structure have a great influence on gas desorption and diffusion rate, and the overall trend of gas desorption rate of Yushuling low-rank gas coal is stable in the first 10 min, while the trend of gas desorption rate of Duanshi high-rank anthracite is faster in the first 4 min and stable in the last 6 min; the correlation between drillings gas desorption index K1 and gas pressure p of Yushuling coal is poorer than that of Δh2, while the correlation between K1 and gas pressure p is better than that of Δh2 for Duanshi coal drillings gas desorption index. The analysis concludes that Δh2 is more suitable as a predictor of the outburst of low-rank coal, and K1 is more suitable as a predictor of the outburst of high-rank coal.

Background and purpose: Immune checkpoint inhibitors (ICIs) have changed the landscape of cancer treatment during the last 10 years. They have significantly extended survival for patients with malignancy. However, immune-related adverse events (irAE) have been reported and attracted attention with widespread use of ICIs. Currently, there is no reliable biomarker to clinically predict the risk of irAE. This study established a risk prediction model of irAE in tumor patients receiving ICIs based on multiple biological indicators. Methods: A total of 91 patients treated in Zhongshan Hospital of Fudan University from October 2018 to December 2020 were included in the study. Patients included in the study were divided into irAE group and control group according to whether they had grade 2 or higher irAE after receiving ICIs. Biological indicators including serum soluble form of suppression of tumorigenicity-2 (sST2), prognostic nutritional index (PNI) and platelet to lymphocyte ratio (PLR) were collected before and after ICIs treatment. Logistic regression model containing these biomarkers was constructed to predict the risk of irAE. Results: A total of 13 patients in the irAE group. Baseline PNI level, baseline PLR level and post-treatment sST2 peak level showed a significant difference between the irAE group and control group (P