该文针对合成孔径雷达(Synthetic Aperture Radar,SAR)图像含有大量的乘性斑点噪声的特点,提出了一种小波域隐类属的马尔可夫随机场(Markov Random Field,MRF)图像分割算法来抑制噪声的影响。考虑到小波的聚集性和持续性,该算法重新构...该文针对合成孔径雷达(Synthetic Aperture Radar,SAR)图像含有大量的乘性斑点噪声的特点,提出了一种小波域隐类属的马尔可夫随机场(Markov Random Field,MRF)图像分割算法来抑制噪声的影响。考虑到小波的聚集性和持续性,该算法重新构造了待分图像小波域模型——以类属为隐状态的混合长拖尾模型,将隐类属的马尔可夫随机场推广到小波域上,并用改进的上下文模型估计尺度间转移概率,最后推导出了新的最大后验(Maximum A Posteriori,MAP)分割公式。仿真结果证明,该算法具有鲁棒性能够有效地抑制噪声对图像的影响,得到准确的分割结果。展开更多
Coda waves are multiply scattered waves that arrive much later than the major waves. Small seismic velocity variations are observed in reservoirs because of small variations in reservoir properties, which affect the f...Coda waves are multiply scattered waves that arrive much later than the major waves. Small seismic velocity variations are observed in reservoirs because of small variations in reservoir properties, which affect the first arrivals. Hence, first arrivals cannot be used to detect small seismic velocity variations. However, small variations can be reliably detected by the coda waves because of the amplification owing to multiple scattering. We investigate the ability of coda wave interferometry to detect seismic velocity variations and monitor time-lapse reservoir characteristics using numerical simulations and experimental data. We use the Marmousi II model and finite-difference methods to build model seismic data and introduce small seismic velocity variations in the target layer. We examine the model seismic data before and after the changes and observe the coda waves. We find that velocity changes can be detected by coda wave interferometry and demonstrate that coda wave interferometry can be used in monitoring time- lapse reservoir characteristics.展开更多
[Objective]The aim of this study was to provide a theoretical basis for the large-scale breeding of Exopalaemon carinicauda. [Method]Effects of salinity fluctuation （S0,S3,S6 and S9 represented salinity fluctuations ...[Objective]The aim of this study was to provide a theoretical basis for the large-scale breeding of Exopalaemon carinicauda. [Method]Effects of salinity fluctuation （S0,S3,S6 and S9 represented salinity fluctuations of 0,3,6 and 9 respectivley） and dietary traditional Chinese herbal medicines （0,1%,2% and 4% respectively） on survival,growth and immunity of E.carinicauda were studied,and its experiment lasted for 60 d. [Result]The results showed that specific growth rate,feed conversion efficiency and superoxide dismutase activity of E.carinicauda in the treatment group with 1% dietary traditional Chinese herbal medicine and S6 salinity fluctuation were higher than those in other treatments,which was significantly higher than the treatment groups with S0,S3 and S9 salinity fluctuation at the same adding level of 1% dietary traditional Chinese herbal medicine. The regression analysis indicated that at S0,S3 and S6 salinity fluctuation,the optimal adding level of dietary traditional Chinese herbal medicines in feeds decreased with the increase of salinity fluctuation,accounting for 2.74%,1.77% and 0.51% respectively. At four adding levels of dietary traditional Chinese herbal medicines,the optimal salinity fluctuation of E.carinicauda also decreased with the increase of dietary traditional Chinese herbal medicines in feeds,accounting for 5.26,4.95,3.54 and 1.97 respectively. [Conclusion]Salinity,dietary traditional Chinese herbal medicines and their interactions have a significant effect on survival,growth and immunity of E.carinicauda,which calls for attentions in the breeding.展开更多
文摘该文针对合成孔径雷达(Synthetic Aperture Radar,SAR)图像含有大量的乘性斑点噪声的特点,提出了一种小波域隐类属的马尔可夫随机场(Markov Random Field,MRF)图像分割算法来抑制噪声的影响。考虑到小波的聚集性和持续性,该算法重新构造了待分图像小波域模型——以类属为隐状态的混合长拖尾模型,将隐类属的马尔可夫随机场推广到小波域上,并用改进的上下文模型估计尺度间转移概率,最后推导出了新的最大后验(Maximum A Posteriori,MAP)分割公式。仿真结果证明,该算法具有鲁棒性能够有效地抑制噪声对图像的影响,得到准确的分割结果。
基金sponsored by the 973 Program of China(No.2013CB228604)the Natural Science Foundation of Shandong Province(No.ZR2013DQ020)+1 种基金the Fundamental Research Funds for the Central Universities(No.15CX08002A)the National Natural Science Foundation of China(No.41374123)
文摘Coda waves are multiply scattered waves that arrive much later than the major waves. Small seismic velocity variations are observed in reservoirs because of small variations in reservoir properties, which affect the first arrivals. Hence, first arrivals cannot be used to detect small seismic velocity variations. However, small variations can be reliably detected by the coda waves because of the amplification owing to multiple scattering. We investigate the ability of coda wave interferometry to detect seismic velocity variations and monitor time-lapse reservoir characteristics using numerical simulations and experimental data. We use the Marmousi II model and finite-difference methods to build model seismic data and introduce small seismic velocity variations in the target layer. We examine the model seismic data before and after the changes and observe the coda waves. We find that velocity changes can be detected by coda wave interferometry and demonstrate that coda wave interferometry can be used in monitoring time- lapse reservoir characteristics.
基金Supported by Key Project of National Science and Technology Supporting Plan during the Eleventh five-year (2006BAD09A06)Openend Fund for Jiangsu Key Laboratory of Marine Biotechnology(HS2007017)Blue Project for Jiangsu Province Office of Education (QN07008)~~
文摘[Objective]The aim of this study was to provide a theoretical basis for the large-scale breeding of Exopalaemon carinicauda. [Method]Effects of salinity fluctuation （S0,S3,S6 and S9 represented salinity fluctuations of 0,3,6 and 9 respectivley） and dietary traditional Chinese herbal medicines （0,1%,2% and 4% respectively） on survival,growth and immunity of E.carinicauda were studied,and its experiment lasted for 60 d. [Result]The results showed that specific growth rate,feed conversion efficiency and superoxide dismutase activity of E.carinicauda in the treatment group with 1% dietary traditional Chinese herbal medicine and S6 salinity fluctuation were higher than those in other treatments,which was significantly higher than the treatment groups with S0,S3 and S9 salinity fluctuation at the same adding level of 1% dietary traditional Chinese herbal medicine. The regression analysis indicated that at S0,S3 and S6 salinity fluctuation,the optimal adding level of dietary traditional Chinese herbal medicines in feeds decreased with the increase of salinity fluctuation,accounting for 2.74%,1.77% and 0.51% respectively. At four adding levels of dietary traditional Chinese herbal medicines,the optimal salinity fluctuation of E.carinicauda also decreased with the increase of dietary traditional Chinese herbal medicines in feeds,accounting for 5.26,4.95,3.54 and 1.97 respectively. [Conclusion]Salinity,dietary traditional Chinese herbal medicines and their interactions have a significant effect on survival,growth and immunity of E.carinicauda,which calls for attentions in the breeding.
