Longkai Dong's research while affiliated with Chinese Academy of Sciences and other places

Publications (9)

Article
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With global warming, permafrost is undergoing degradation, which may cause thawing subsidence, collapse, and emission of greenhouse gases preserved in previously frozen permafrost, change the local hydrology and ecology system, and threaten infrastructure and indigenous communities. The Qinghai-Tibet Plateau (QTP) is the world’s largest permafrost...
Article
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The Coherent Pixels Technique Interferometry Synthetic Aperture Radar (CPT-InSAR) method of inverting surface deformation parameters by using high-quality measuring points possesses the flaw inducing sparse measuring points in non-urban areas. In this paper, we propose the Adaptive Coherent Distributed Pixel InSAR (ACDP-InSAR) method, which is an a...
Article
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The Qinghai-Tibet Railway (QTR) is the railway with the highest elevation and longest distance in the world, spanning more than 1142 km from Golmud to Lhasa across the continuous permafrost region. Due to climate change and anthropogenic activities, geological disasters such as subsidence and thermal melt collapse have occurred in the QTR embankmen...
Article
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The three-dimensional (3-D) displacements of mining areas is the basis of studying the mining subsidence law and obtaining surface movement parameters. The traditional multi-temporal interferometry synthetic aperture radar (InSAR) technology can only obtain the surface deformation in line-of-sight (LOS) direction, even if some methods can obtain th...
Article
Underground mining causes many forms of surface deformation, including vertical subsidence as well as strike and dip horizontal displacement. Differential interferometric synthetic-aperture radar (D-InSAR) has become a widely applied technique for precise and detailed mapping of the Earth's surface deformation caused by underground mining. However,...

Citations

... UHV transmission lines usually traverse long distances. As compared with the traditional geodetic and GPS measurement methods [14,15], the satellite-based synthetic aperture radar (SAR) monitoring method can meet the accuracy of the surface deformation monitoring demand along the lines and also has a broader coverage area and higher cost benefits [16][17][18]. A long-term InSAR method is usually used to obtain the time-series analysis results by interpreting the permanent scatterers in the InSAR datasets [19]. ...
... To address the inherent limitation of sparse measurements in non-urban areas in the conventional coherent pixels technique InSAR (CPT-InSAR), an adaptive coherent distributed pixels selection method was integrated into the CPT-InSAR processing chain [35]. DS pixels were identified by classical statistical testing and their phases were also optimized by the joint use of the phase triangle algorithm (PTA) and Eigen decompositionbased maximum likelihood estimator of interferometric phase (EMI) [35]. ...
... To discover distributed scatterers, SAR data were analyzed for statistical hypothesis testing (KD test), as previously reported by Ferretti et al. [55,56]. Prior to the deformation analysis, the Delaunay triangle network was built to ensure the spatial connectivity of all permanent scatterer and distributed scatterer points [57]. On the completion of constructing the network, the process of selecting the best point set was carried out using distance and connectivity threshold. ...
... Parallel coherent scatterers InSAR (P-CSInSAR) approaches for processing Sentinel-1 data are proposed in [206][207][208], where several parallelism strategies are applied for each processing step according to different levels of granularity (burst-level, line-level, and block-level) [208]. The adopted strategy includes both intra-node (multithreading) and inter-node (message-passing) parallelisms. ...
... As one of the main geological hazards in mining areas, surface subsidence caused by coal mining seriously affects prevention and control of ecological environment and regional sustainable development in mining areas, and the study of mining subsidence has been a significant topic in academia (Ammirati et al., 2020;Dong et al., 2021). The airborne LiDAR is an important technical means for collecting large-scale and continuously distributed three-dimensional geospatial information. ...
... Using supercomputers or distributed computing systems, such as CASearth Cloud Infrastructure Platform [15], and ESA's G-POD environment [16], is a way to improve the data processing efficiency, but it is too expensive to be popularized. Another way is to segment a large image into small blocks, which can significantly reduce the computation burden and complexity in one block and improve the efficiency of data processing. ...