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Geospatial technology has been extensively researched and applied in the urban spatial planning field. However, mountainous urban planning needs to consider not only the complex terrain but also the accessibility of the landscape to landmark buildings. Therefore, geospatial techniques and landscape sight analysis play important roles in formulating effective urban building height control measures. This article uses the Nanshan Temple and Nanping Academy of Classical Learning and its surrounding architectural planning as the research objects, constructs a digital elevation model through geospatial technology combined with Grasshopper parameterization, and calculates the visible area when viewed from different positions. To maintain the accessibility of the landscape to the landmark buildings, the layout, building height and location of the planning area are determined. The research shows that (1) through geospatial technology, landscape sightline analysis, linear projection and collision detection methods can be used to accurately calculate landscape sightline interruption points and occlusion areas around historical and cultural buildings. We concluded that the optimal viewshed protection range is a radius of 2000 m. (2) Compared with a design based on a surrounding height of 60 m, the method in this study increased the number of visible viewpoints by approximately 123.84%, while the number of invisible viewpoints decreased by approximately 21.03%. (3) Based on the sightline protection scope, the heights of the blocks in the protection zone are further calculated. Within a radius of 1000 m, a 52.78 m height limit of planned plots is recommended. Within a radius of 1500 m, a 40.87 m height limit of the planned plot is recommended. Within a radius of 2000 m, the height of the planned plot should be controlled at 24.79 m. Based on this, the specific building space arrangement can be reasonably formulated. (4) After optimizing the existing visual corridors in the reserve, the area of the viewsheds expanded from 13.0% to 19.1%. (5) Finally, this study also considered plant factors. The recommended height for plant landscapes is as follows. Woodland on hillsides should be reduced from the original 10-12 to 4.74-8.51 m. Garden land in flat areas should be reduced from the original 9 to 6.38-3.36 m. This study uses the geospatial technology landscape sight analysis method to reveal the impact of landscape sight on the spatial distribution of mountainous cities with cultural landmarks and, at the same time, provides a new method and strategy for the spatial planning of mountainous cities. [ABSTRACT FROM AUTHOR]

Urban informal settlements (UISs) are densely populated and poorly developed residential areas in urban areas. The mapping of UISs using remote sensing is crucial for urban planning and management. However, the large-scale extraction of UISs is impeded by the labor-intensive task of collecting numerous training samples and the lack of automatic and effective city partition. To overcome these challenges, we proposed a large-scale extraction framework for UISs based on semantic segmentation of highresolution remote sensing images. Utilizing Deeplab V3 Plus as the foundational extraction model, the proposed framework introduces fast sample collection based on GLCM features. Besides, an automatic city partition approach combined with clustering and fine-tuning was proposed to enhance the performance on extracting a specific category of UISs. The results of the case study conducted in 36 major Chinese cities show that the proposed framework achieved good performance, with an overall F1 score of 85.76%. Furthermore, comparative assessments were performed to demonstrate the effectiveness of automatic city partition. The proposed framework offers a practical approach for the largescale extraction of UISs, which holds great significance for sustainable development, poverty estimation, infrastructure construction, and urban planning. [ABSTRACT FROM AUTHOR]