Low Earth orbit (LEO) satellites located at altitudes of 500 km~1500 km can carry much stronger signals and move faster than medium (MEO) about a 20,000 altitude. Taking advantage these features, LEO promise to make contributions navigation positioning where global satellite system (GNSS) are blocked as well the rapid convergence precise point (PPP). In this paper, LEO-based optimal augmentation constellations designed by non-dominated sorting genetic algorithm III (NSGA-III) (GA),...

The Woda area in the upper Jinsha River has steep terrain and broken structures, causing landslide disasters frequently. Here, we used distributed scatterer interferometric SAR (DS-InSAR) method to monitor analyze area. With DS-InSAR method, derived deformation of from 106 Sentinel-1A ascending images acquired between 5 November 2014 4 September 2019 102 descending 31 October 11 2019. obvious advantage compared persistent (PS) InSAR (PS-InSAR) is that densities monitoring points were...

Nonlinear deformation is a dynamically changing pattern of multiple surface deformations caused by groundwater overexploitation, underground coal mining, landslides, urban construction, etc., which are often accompanied severe damage to structures or lead major geological disasters; therefore, the high-precision monitoring and prediction nonlinear significant. Traditional deep learning methods encounter challenges such as long-term dependencies difficulty capturing complex spatiotemporal...

Disease and detection is crucial for the protection of forest growth, reproduction, biodiversity. Traditional methods face challenges such as limited coverage, excessive time resource consumption, poor accuracy, diminishing effectiveness disease prevention control. By addressing these challenges, this study leverages drone remote sensing data combined with deep object models, specifically employing YOLO-v3 algorithm based on loss function optimization, efficient accurate tree diseases pests....

The meteorological reanalysis data has been widely applied to derive zenith tropospheric delay (ZTD) with a high spatial and temporal resolution. With the rapid development of artificial intelligence, machine learning also begins as high-efficiency tool be employed in modeling predicting ZTD. In this paper, we develop three new regional ZTD models based on least squares support vector (LSSVM), using both International GNSS Service (IGS)-ZTD products European Centre for Medium-Range Weather...

Ground-based synthetic aperture radar interferometry (GB-InSAR) has the characteristics of high precision, temporal resolution, and spatial is widely used in highwall deformation monitoring. The traditional GB-InSAR real-time processing method to process whole data set or group time sequence. This type takes up a lot computer memory, low efficiency, cannot meet timeliness slope monitoring, perform prediction disaster warning forecasting. In response this problem, paper proposes series based...

As one of the major forms geological disaster, landslides cause huge casualties and economic losses in China every year. Given importance landslide prediction, it is a challenging task due to difficulties efficiently leveraging spatial–temporal information for enhanced prediction. This paper presents novel CNN-GRU model improve predictions with following contributions. First, this explicitly models spatial correlation dataset constructs time-sequence deformation prediction that greatly...

The Xishan coal mine area in Beijing, China has a long history of mining. Many landslide hazards, addition to collapses and ground fractures, have occurred this area. This study used multi-temporal satellite images extract region’s deformation information, identify landslides analyze the evolution process these landslides. Taking Anzigou ditch as an example, we investigate “Quarry–Landslide–Mudslide” disaster chain model. We found that is closely related geological conditions, usually goes...

Typical unsupervised classification of hyperspectral imagery (HSI) uses a Gaussian mixture model to determine intensity similarity pixels. However, the existence mixed pixels in HSI tends reduce effectiveness measure and leads large errors. Since semantic class is always dominated by particular endmember, pixel can be better classified identifying dominant endmember. By exploiting spectral (SMM) that describes endmemberabundance pattern pixels, discriminative ability enhanced. A Bayesian...

Coal-mining subsidence causes ground fissures and destroys surface structures, which may lead to severe casualties economic losses. Time series interferometric synthetic aperture radar (TS-InSAR) plays an important role in deformation detection monitoring without the restriction of weather sunlight conditions. In addition, probability integral method (PIM) is a movement model that widely used field mining subsidence. recent years, integration TS-InSAR PIM has been extensively studied. this...

BeiDou Navigation Satellite System (BDS) has got the global service capability after launch of 55th BDS-3 satellite on June 23, 2020. Currently, BDS is operated based both second generation (BDS-2, with 15 satellites transmitting triple frequency signals) and third (BDS-3, 30 providing services from five signals). To make full use BDS-2 + signals (B1I, B2I, B3I, B1C, B2a), this paper introduces an undifferenced uncombined Precise Point Positioning (PPP) model by using single/dual/triple...

Reliable and continuous navigation solutions are essential for high-accuracy location-based services. Currently, the real-time kinematic (RTK) based Global Positioning System (GPS) is widely utilized to satisfy such requirements. However, RTK's accuracy continuity limited by insufficient number of visible satellites increasing length base-lines between reference-stations rovers. Recently, benefiting from development precise point positioning (PPP) BeiDou satellite systems (BDS), issues...

Time series interferometric synthetic aperture radar (TS-InSAR) has been a powerful tool for monitoring land surface deformation in the last two decades. Atmospheric effects cause large-scale delays InSAR observations, which is one of difficulties facing calculations from differential (D-InSAR) and time-series InSAR. Currently, atmospheric delay derived mainly auxiliary data sources such as global navigation satellite system (GNSS) moderate-resolution imaging spectroradiometer (MODIS), but...

This paper presents a new method to correct rail errors of ground-based synthetic aperture radar (GB-SAR) in the discontinue mode. Generally, light positioning is performed mark GB-SAR position discontinuous observation Usually we assume there no difference between marked and real installation position. But fact, it hard keep positions two campaigns same, so repositioning cannot be neglected. In order solve this problem, propose an algorithm error after analysing geometry. Results simulation...