Edge detection method for remote sensing image based on morphological variable structuring element

There are problems such as incomplete edges and poor noise suppression when a single fixed morphological structuring element is used to detect the edges in remote sensing images. For this reason, a morphological edge detection method for remote sensing image based on variable structuring element is proposed. Firstly, the structuring elements with different scales and multiple directions are constructed according to the diversity of remote sensing imagery targets. In order to suppress the noise of the target background and highlight the edge of the image target in the remote sensing image by adaptive Top hat and Bottom hat transform, the corresponding adaptive morphological operations are constructed based on variable structuring elements; Secondly, adaptive morphological edge detection is used to obtain multiple images with different scales and directional edge features; Finally, the image edges are obtained by weighted summation of each direction edge, and then the least square is used to fit the edges for accurate location of the edge contour of the target. The experimental results show that the proposed method not only can detect the complete edge of remote sensing image, but also has high edge detection accuracy and superior anti-noise performance. Compared with classical edge detection and the morphological edge detection with a fixed single structuring element, the proposed method performs better in edge detection effect, and the accuracy of detection can reach 95 %

淮南地区中——新元古界LA-ICP-MS碎屑锆石U-Pb年龄及地质意义

淮南地区中—新元古代地层保存有大量精美的宏体碳质压膜化石和有机质壁微体化石,是新元古代大冰期之前生命演化的重要实证材料。然而,淮南地区中—新元古代地层的沉积时间仍未得到较好的约束,碎屑锆石年龄随地层层序的变化特征也未明确。为此本文对碎屑锆石数据较少的淮南寿县地区中—新元古代地层开展了系统的碎屑锆石U-Pb同位素测年。结果显示,八公山组碎屑锆石以古元古代锆石为主体,无小于1600 Ma的锆石;刘老碑组和寿县组碎屑锆石以中元古代锆石为主体,中元古代之前的锆石较少。综合已知的碎屑锆石年龄以及与邻区地层的对比,约束寿县组沉积时间为~950—~945 Ma,刘老碑组沉积时间为~1110—~945 Ma。淮南与鲁西地区中—新元古代地层的碎屑锆石年龄谱、沉积序列、沉积环境和化石产出相似,两地地层可相互对比。淮南地区中元古代早期及之前的碎屑锆石源区可能在华北克拉通东部,而中元古代晚期的碎屑锆石的源区则可能不在华北克拉通。

Efficient aero-structural design optimization: Coupling based on reverse iteration of structural model

Traditional coupled multi-disciplinary design optimization based on computational fluid dynamics/computational structure dynamics(CFD/CSD)aims to optimize the jig shape of aircraft,and general multi-disciplinary design optimization methodology is adopted.No special consideration is given to the aircraft itself during the optimization.The main drawback of these methodologies is the huge expanse and the low efficiency.To solve this problem,we put forward to optimize the cruise shape directly based on the fact that the cruise shape can be transformed into jig shape,and a methodology named reverse iteration of structural model(RISM)is proposed to get the aero-structural performance of cruise shape.The main advantage of RISM is that the efficiency can be improved by at least four times compared with loosely-coupled aeroelastic analysis and it maintains almost the same fidelity of loosely-coupled aeroelastic analysis.An optimization framework based on RISM is proposed.The aerodynamic and structural performances can be optimized simultaneously in this framework,so it may lead to the true optimal solution.The aerodynamic performance was predicted by N-S solver in this paper.Test shows that RISM predicts the aerodynamic and structural performances very well.A wing-body configuration was optimized by the proposed optimization framework.The drag and weight of the aircraft are decreased after optimization,which shows the effectiveness of the proposed framework.