SmartQSM: a novel quantitative structure model using sparse-convolution-based point cloud contraction for reconstruction and analysis of individual tree architecture - Jie Yang; Huaiqing Zhang; Jinyang Li; Haoyue Yang; Tian Gao; Tingdong Yang; Jiaxin Wang; Xiaoli Zhang; Ting Yun; Yuxin Duanmu; Sihan Chen; Yukai Shi (ISPRS Journal of Photogrammetry and Remote Sensing, 2026)