Nanjing University of Information Science & Technology

National Climate Center

Nanjing University of Information Sci. & Tech.

Other

Guojie Wang

Yanjun Wang

Tong Jiang

Buda Su

Aiqing Feng

Guofu Wang

Wen Dai

Bo Wang

Jianqing Zhai

Jinlong Huang

Zhen Dong

Ruibo Qiu

Mingyue Lu

Kai Chen

Ronald R Marquardt

Qigen Lin

Zifan Liang

Xikun Wei

Zicong Luo

Jiaxing Fan

Xiao Hao

Xiaodong Zheng

Zhiqun Zhang

Aili Liu

Lijuan Miao

Zhibo Gan

A photogrammetric ground control point quality evaluation method based on Monte Carlo test relates to the field of photogrammetry technology. Firstly, aerial photographs and ground control points from a survey area are obtained, the ground control points are numbered, the aerial photographs are performed with point-placing and aerial triangulation densification. Secondly, a Monte Carlo test experiment is designed, a certain number of the ground control points are selected as control points with the rest as check points, ensuring each ground control point as the control point a certain number of times, and average errors of the ground control points are calculated. Thirdly, average values of the average errors of the ground control points are calculated, standard deviations of the average errors of the ground control points are calculated. Finally, a quality coefficient Q of each ground control point is calculated and evaluated according to quality evaluation standards.

Photogrammetric ground control point quality evaluation method based on Monte Carlo test

A sand dune extraction method based on fusion of positive-negative terrains and light shading includes: obtaining an original digital elevation model of a study region; using a neighborhood analysis method to process the original digital elevation model of the study region, thereby extracting a positive terrain region and a negative terrain region of the study region; using a lighting shading method to perform six directional lighting simulation calculations on each pixel of the original digital elevation model of the study region to obtain a lighting shading map, and extracting a lighting region and a shadow region of the study region from the lighting shading map; using an embedding method to fuse the positive terrain region and the negative terrain region with the lighting region and the shadow region. The sand dune extraction method is a method for remote sensing monitoring and governance of desertification regions.

Sand dune extraction method based on fusion of positive-negative terrains and light shading

A high-temperature disaster forecast method based on a directed graph neural network is provided, and the method includes the following steps: S, performing standardization processing on meteorological elements respectively to scale the meteorological elements into a same value range; S, taking the meteorological elements as nodes in the graph, and describing relationships among the nodes by an adjacency matrix of graph; then learning node information by a stepwise learning strategy and continuously updating a state of the adjacency matrix; S, training the directed graph neural network model after determining a loss function, obtaining a model satisfying requirements by adjusting a learning rate, an optimizer and regularization parameters as a forecast model, and saving the forecast model; and S, inputting historical multivariable time series into the forecast model, changing an output stride according to demands, and thereby obtaining high-temperature disaster forecast for a future period of time.

High-temperature disaster forecast method based on directed graph neural network

The present disclosure provides a meteorological big data fusion method based on deep learning, including the following steps: constructing multi-source meteorological data samples; according to an original resolution of different climate variables, selecting a corresponding super-resolution multiple to obtain an optimized super-resolution module under the constraint of maximizing information retention efficiency; constructing a spatial-temporal attention module using a focused attention mechanism, and selecting a corresponding time stride according to periodic characteristics of different climate variables; constructing a meteorological data fusion model in combination with the optimized super-resolution model and the spatial-temporal attention module; taking a minimum resolution of climate variables as a loss function, and training the meteorological data fusion model with the multi-source meteorological data samples; and importing the acquired real-time meteorological data from multiple data sources into the trained meteorological data fusion model to obtain high-resolution fused meteorological data.

Meteorological big data fusion method based on deep learning

An evaluation method for evaluating a precipitation-induced landslide disaster loss under climate change is provided. The evaluation method belongs to the technical field of geological disaster prevention and treatment. The evaluation method uses a physical process based model, in considering of spatial heterogeneity of land-surface features of grids in the area, to obtain precipitation thresholds corresponding to the respective grids in the area having the spatial heterogeneity. Historical data and climate model data are taken in combination to select suitable climate models, and the model then is used to simulate landslide prone zones and possible influence zones caused by landslides. An influence zones simulated by the evaluation method can better match disaster loss grid data, which can solve the problem that climate change scenarios and influence of landslide are difficult to be evaluated in landslide disaster evaluation.

Evaluation method for evaluating precipitation-induced landslide disaster loss under climate change

The present application provides a method and system for identifying extreme climate events. The method acquires climate index (CI) grid data of a to-be-identified region within an extreme climate time period, and gradually expands each of event centers in the to-be-identified region, until CI values of all grids adjacent to the event center are not greater than a CI threshold. The method can obtain extreme climate impacted areas of extreme climate events in the to-be-identified region, and can further obtain CI intensities of the extreme climate events by average calculation. The method can obtain three pieces of dimension information on each of the extreme climate events in the to-be-identified region, including an extreme climate impacted area, a CI intensity and a duration. Therefore, the method can identify the extreme climate events more comprehensively.

Method and system for identifying extreme climate events

A landslide recognition method based on Laplacian pyramid remote sensing image fusion includes: performing original remote sensing image reconstruction based on extracted local features and global features of remote sensing images through a Laplacian pyramid fusion module to generate a fused image, constructing a deep learning semantic segmentation model through a semantic segmentation network, labeling the fused image to obtain a dataset of landslide disaster label map, and training the deep learning semantic segmentation model by the dataset, and then storing when a loss curve is fitted and a landslide recognition accuracy of remote sensing image of the deep learning semantics segmentation model meets a requirement by modifying a structure of the semantic segmentation network and adjusting parameters of the deep learning semantics segmentation model. Combined with the image fusion model based on Laplacian pyramid, the method can provide effective decision-making basis for prevention and mitigation of landslide disasters.

Landslide recognition method based on laplacian pyramid remote sensing image fusion

A method for flood disaster monitoring and disaster analysis based on vision transformer is provided. It includes: step (1), constructing a bi-temporal image change detection model based on vision transformer; step (2), selecting bi-temporal remote sensing images to make flood disaster labels; and step (3), performing flood monitoring and disaster analysis according to the bi-temporal image change detection model constructed in the step (1). In combination with the bi-temporal image change detection model based on an advanced vision transformer in deep learning and radar data which is not affected by time and weather and has strong penetration ability, data when floods occur can be obtained and recognition accuracy is improved.

Method for flood disaster monitoring and disaster analysis based on vision transformer

A method of detecting via a solid-phase assay the amount of biological activity, identity and/or the quantity of a biologically active substance is disclosed. The method utilizes the biological activity of the substance itself to provide the method of detection. The method provides competitive and noncompetitive assays.

Solid-phase activity assay for biologically active substance

Growing community of inventors

Nanjing, China

Guojie Wang