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The spatial distribution of night-time lights (NTL) provides a new perspective for studying the range and influence of human activities. However, most studies employing NTL time series are based on monthly or annual composite data, and time series studies incorporating sliding windows are currently lacking. Therefore, using National Polar-Orbiting Partnership's visible infrared imaging radiometer suite (NPP-VIIRS) night-time light remote sensing (NTLRS) data, VNP46A2, toponym, and Yunnan census statistical data, this study proposes a sliding-window-based NTLRS time series detection and analysis method. We extracted ethnic minority areas on the PyCharm platform using ethnic minority population proportion data and toponym and excluding data representing interference from urban areas. We used a sliding window approach to analyze NTLRS time series data of each ethnic group and calculated the cosine similarity between the NTL brightness curve of original data and the sliding window analysis result. The cosine similarity was greater than 0.96 from 2018 to 2020; we also conducted a field trip to the 2019 Torch Festival to demonstrate the applicability of the employed method. Finally, the temporal and spatial pattern of the Torch Festival was analyzed using the festival in Yunnan Province as an example. Results showed that the Torch Festival, mostly celebrated by the Yi ethnic group, was usually held on the 24th (and ranged from the 22nd to 26th) day in the sixth month of the lunar calendar (LC) every year. We found that during the Torch Festival, the greater the increase in the percentage of NTL brightness reduction in the main urban area of Kunming, the greater the percentage of ethnic minorities' NTL brightness. The width of the sliding window can be adjusted appropriately according to the research objective, with these results showing good continuity. Our study presents a new application of the sliding window approach in the field of remote sensing, suitable for research into festivals related to night lights and fire all over the world. [ABSTRACT FROM AUTHOR]

The water corridors between the Guanlei Port and the Qingsheng Port on the Lancang – Mekong River are important waterway for Yunnan and Southeast Asian countries. However, there are certain unpredictable safety hazards due to its location bordering multiple countries, complex terrain, sparse human settlements and inconvenient transportation. To help enhancing the safety of the Lancang – Mekong River international waterway, this paper used satellite imagery to interpret safety factors such as fault structures, channel width, rapids, vegetation coverage, river curvature, human settlements and transportation conditions. Based on analytic hierarchy process (AHP) , this research assessed the shipping safety of the waterway, analysed the effects of various factors on navigation, and made suggestions on the shipping safety which is important in the border areas. The results show that the Meisai section of the Mekong River has the shipping safety at level 1 where the limited joint patrol is proposed. The navigation channel from Guanlei Port to Wanxianwotang has the shipping safety at levels 2 & 3 where the intermediate effort of the joint patrol is suggested. The waterway from Wanxianwotang to Wannanpen has the shipping safety at levels 4 & 5 where the strong presence of the joint patrol is recommended. [ABSTRACT FROM AUTHOR]