The characteristics of vertical crustal movement in Chinese mainland are studied, and the ideas and principles for dividing active blocks according to the map of recent vertical crustal deformation rate in China is pr...The characteristics of vertical crustal movement in Chinese mainland are studied, and the ideas and principles for dividing active blocks according to the map of recent vertical crustal deformation rate in China is proposed. As a result, Chinese mainland is divided into 2 first-grade blocks, the east and west block, 6 second-grade blocks, the Northeast China, North China, East China, Xizang (Tibet), Gansu-Qinghai-Xizang (Gan-Qing-Zang) and Xinjiang block, and 16 third-grade blocks. The boundaries of active blocks divided in this paper are generally consistent with the pattern of neotectonic movement with some local difference. It shows that the recent crustal activity in Chinese mainland inherits the neotectonic movement occurred since the Quaternary, while some new activity tendencies appear.展开更多
Today’s forensic science introduces a new research area for digital image analysis formultimedia security.So,Image authentication issues have been raised due to the wide use of image manipulation software to obtain a...Today’s forensic science introduces a new research area for digital image analysis formultimedia security.So,Image authentication issues have been raised due to the wide use of image manipulation software to obtain an illegitimate benefit or createmisleading publicity by using tempered images.Exiting forgery detectionmethods can classify only one of the most widely used Copy-Move and splicing forgeries.However,an image can contain one or more types of forgeries.This study has proposed a hybridmethod for classifying Copy-Move and splicing images using texture information of images in the spatial domain.Firstly,images are divided into equal blocks to get scale-invariant features.Weber law has been used for getting texture features,and finally,XGBOOST is used to classify both Copy-Move and splicing forgery.The proposed method classified three types of forgeries,i.e.,splicing,Copy-Move,and healthy.Benchmarked(CASIA 2.0,MICCF200)and RCMFD datasets are used for training and testing.On average,the proposed method achieved 97.3% accuracy on benchmarked datasets and 98.3% on RCMFD datasets by applying 10-fold cross-validation,which is far better than existing methods.展开更多
Low earth orbit(LEO)mega-constellations can provide global low-latency high bandwidth coverage compared to the terrestrial network.The time-varying topology of satellite networks and the uneven traffic distribution le...Low earth orbit(LEO)mega-constellations can provide global low-latency high bandwidth coverage compared to the terrestrial network.The time-varying topology of satellite networks and the uneven traffic distribution lead to the mismatch between satellites and users,resulting in the waste of satellite resources and the degradation of user performance.Through negotiation with neighbors,the traditional terrestrial cell breathing continuously converges to the optimal cell size in the face of user tides,but this method is difficult to converge timely when facing rapid and extreme flow changes caused by the rapid movement of satellites.This paper presents a fast adaptive cell breathing scheme(Fa B)through sub-block division and satellite cell initialization and adjustment.Fa B divides the ground into sub-blocks according to the user density.When the satellite moves in the same sub-block,the step size of breathing is adjusted according to the cell size difference between the previous satellite and the current satellite.When the satellite switches between different sub-blocks,the initial value of the cell is determined according to the density of the new sub-block.In addition to negotiating with neighboring satellites,this scheme also introduces location information to directly adjust the parameters of cell breathing and decrease the time of cell breathing convergence.From the real constellation data-driven simulation,we conclude that Fa B can quickly adjust the size of the cell with the location changing,and the utilization rate is increased by 2.66 times compared to the method with no cell breathing,and by2.37 times compared to the method with cell breathing without location information.展开更多
基金The developing and programming project G19980407 of National Key Basic Researches.
文摘The characteristics of vertical crustal movement in Chinese mainland are studied, and the ideas and principles for dividing active blocks according to the map of recent vertical crustal deformation rate in China is proposed. As a result, Chinese mainland is divided into 2 first-grade blocks, the east and west block, 6 second-grade blocks, the Northeast China, North China, East China, Xizang (Tibet), Gansu-Qinghai-Xizang (Gan-Qing-Zang) and Xinjiang block, and 16 third-grade blocks. The boundaries of active blocks divided in this paper are generally consistent with the pattern of neotectonic movement with some local difference. It shows that the recent crustal activity in Chinese mainland inherits the neotectonic movement occurred since the Quaternary, while some new activity tendencies appear.
基金funded by Princess Nourah bint Abdulrahman University Researchers Supporting Project number(PNURSP2024R236),Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.
文摘Today’s forensic science introduces a new research area for digital image analysis formultimedia security.So,Image authentication issues have been raised due to the wide use of image manipulation software to obtain an illegitimate benefit or createmisleading publicity by using tempered images.Exiting forgery detectionmethods can classify only one of the most widely used Copy-Move and splicing forgeries.However,an image can contain one or more types of forgeries.This study has proposed a hybridmethod for classifying Copy-Move and splicing images using texture information of images in the spatial domain.Firstly,images are divided into equal blocks to get scale-invariant features.Weber law has been used for getting texture features,and finally,XGBOOST is used to classify both Copy-Move and splicing forgery.The proposed method classified three types of forgeries,i.e.,splicing,Copy-Move,and healthy.Benchmarked(CASIA 2.0,MICCF200)and RCMFD datasets are used for training and testing.On average,the proposed method achieved 97.3% accuracy on benchmarked datasets and 98.3% on RCMFD datasets by applying 10-fold cross-validation,which is far better than existing methods.
基金the National Key Research and Development Plan of China(No.2018YFB1800301)the National Natural Science Foundation of China(No.62132009)+1 种基金the Youth Fund of National Natural Science Foundation of China(No.61902214)the Tsinghua University-China Mobile Communications Group Co.,Ltd.Joint Institute。
文摘Low earth orbit(LEO)mega-constellations can provide global low-latency high bandwidth coverage compared to the terrestrial network.The time-varying topology of satellite networks and the uneven traffic distribution lead to the mismatch between satellites and users,resulting in the waste of satellite resources and the degradation of user performance.Through negotiation with neighbors,the traditional terrestrial cell breathing continuously converges to the optimal cell size in the face of user tides,but this method is difficult to converge timely when facing rapid and extreme flow changes caused by the rapid movement of satellites.This paper presents a fast adaptive cell breathing scheme(Fa B)through sub-block division and satellite cell initialization and adjustment.Fa B divides the ground into sub-blocks according to the user density.When the satellite moves in the same sub-block,the step size of breathing is adjusted according to the cell size difference between the previous satellite and the current satellite.When the satellite switches between different sub-blocks,the initial value of the cell is determined according to the density of the new sub-block.In addition to negotiating with neighboring satellites,this scheme also introduces location information to directly adjust the parameters of cell breathing and decrease the time of cell breathing convergence.From the real constellation data-driven simulation,we conclude that Fa B can quickly adjust the size of the cell with the location changing,and the utilization rate is increased by 2.66 times compared to the method with no cell breathing,and by2.37 times compared to the method with cell breathing without location information.
