近年来,面向机器视觉视频的研究和应用越来越广泛,这对此类视频的存储和传输都提出了巨大的挑战。视频编码标准如多功能视频编码(Versatile Video Coding,VVC)能实现高效的全分辨率压缩与重建,但是对机器视觉任务而言,这种压缩方法是有...近年来,面向机器视觉视频的研究和应用越来越广泛,这对此类视频的存储和传输都提出了巨大的挑战。视频编码标准如多功能视频编码(Versatile Video Coding,VVC)能实现高效的全分辨率压缩与重建,但是对机器视觉任务而言,这种压缩方法是有冗余的。因此,提出了一种在VVC编码过程中结合显著性检测的视频编码方法用于机器任务,用实例分割网络掩膜基于区域的卷积神经网络(Mask Region-based Convolutional Neural Network,Mask R-CNN)获得包含对象的二进制掩膜,并依此判定是否为感兴趣区域,指导VVC编码过程中编码树单元(Coding Tree Unit,CTU)的量化参数的偏移。实验证明,与VVC基线方法相比,所提方法可以在相似的检测精度下节省一定的比特率。展开更多
A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation...A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation of black hole interior “space-and-time-reversal”. Specifically, it is proposed that the “singularity” space of the black hole interior is time-like and the expansion time of the black hole interior is space-like. The resemblance of this new insider interpretation to our own expanding and redshifting big bang universe is compelling.展开更多
SiC-MgAl_(2)O_(4) composites with SiAlON polytypoids(12H and 21R)as the bonding phases were prepared using SiC fine powder,MgAl_(2)O_(4)fine powder and Al powder as raw materials.The effects of the firing temperature ...SiC-MgAl_(2)O_(4) composites with SiAlON polytypoids(12H and 21R)as the bonding phases were prepared using SiC fine powder,MgAl_(2)O_(4)fine powder and Al powder as raw materials.The effects of the firing temperature and the mass ratio of SiC to MgAl_(2)O_(4) on the formation of SiAlON polytypoids as well as on the properties of samples were studied.The formation mechanism of SiAlON polytypoids was discussed.The results show that firing at 1650℃in the nitrogen atmosphere,SiC-MgAl_(2)O_(4) composites with SiAlON polytypoids can be obtained.With the gradual increase of the mass ratio of SiC to MgAl_(2)O_(4) in the raw materials,12H forms first,and then coexists with 21H,finally,all 12H converts into 21R in samples.Both phases are plate crystals with flat and smooth edges.Compared with 21R,12H is conducive to improving the density and the cold mechanical properties of materials.After firing at 1650℃in the nitrogen atmosphere,with the mass ratio of SiC to MgAl_(2)O_(4) of 6:4,the sample has the cold modulus of rupture of 27 MPa,showing the optimal performance.展开更多
文摘近年来,面向机器视觉视频的研究和应用越来越广泛,这对此类视频的存储和传输都提出了巨大的挑战。视频编码标准如多功能视频编码(Versatile Video Coding,VVC)能实现高效的全分辨率压缩与重建,但是对机器视觉任务而言,这种压缩方法是有冗余的。因此,提出了一种在VVC编码过程中结合显著性检测的视频编码方法用于机器任务,用实例分割网络掩膜基于区域的卷积神经网络(Mask Region-based Convolutional Neural Network,Mask R-CNN)获得包含对象的二进制掩膜,并依此判定是否为感兴趣区域,指导VVC编码过程中编码树单元(Coding Tree Unit,CTU)的量化参数的偏移。实验证明,与VVC基线方法相比,所提方法可以在相似的检测精度下节省一定的比特率。
文摘A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation of black hole interior “space-and-time-reversal”. Specifically, it is proposed that the “singularity” space of the black hole interior is time-like and the expansion time of the black hole interior is space-like. The resemblance of this new insider interpretation to our own expanding and redshifting big bang universe is compelling.
文摘SiC-MgAl_(2)O_(4) composites with SiAlON polytypoids(12H and 21R)as the bonding phases were prepared using SiC fine powder,MgAl_(2)O_(4)fine powder and Al powder as raw materials.The effects of the firing temperature and the mass ratio of SiC to MgAl_(2)O_(4) on the formation of SiAlON polytypoids as well as on the properties of samples were studied.The formation mechanism of SiAlON polytypoids was discussed.The results show that firing at 1650℃in the nitrogen atmosphere,SiC-MgAl_(2)O_(4) composites with SiAlON polytypoids can be obtained.With the gradual increase of the mass ratio of SiC to MgAl_(2)O_(4) in the raw materials,12H forms first,and then coexists with 21H,finally,all 12H converts into 21R in samples.Both phases are plate crystals with flat and smooth edges.Compared with 21R,12H is conducive to improving the density and the cold mechanical properties of materials.After firing at 1650℃in the nitrogen atmosphere,with the mass ratio of SiC to MgAl_(2)O_(4) of 6:4,the sample has the cold modulus of rupture of 27 MPa,showing the optimal performance.
