投影子空间正交性测试法(Test of Orthogonality of Projected Subspaces,TOPS)是利用宽带信号多个频点的子空间的正交性完成波达方向(Direction of Arrival,DOA)估计。该方法依赖参考频率点的选择,易产生伪峰,且在低信噪比时性能差。...投影子空间正交性测试法(Test of Orthogonality of Projected Subspaces,TOPS)是利用宽带信号多个频点的子空间的正交性完成波达方向(Direction of Arrival,DOA)估计。该方法依赖参考频率点的选择,易产生伪峰,且在低信噪比时性能差。针对该问题,提出一种聚焦的FTOPS算法。首先利用RCM(Reduced Covariance Matrix)法消除了噪声,然后将各个频点的信号子空间(Signal Subspace)聚焦到任意参考频点的Signal Subspace,利用该参考频点的Signal Subspace与阵列方向矢量的正交投影矩阵之间的正交性完成DOA估计。仿真结果表明,该方法不依赖于参考频点的选择,能有效消除伪峰,在低信噪比条件下性能优于传统TOPS算法。展开更多
提出了一种新的宽带DOA估计方法:频域子空间正交性测试方法(TOFS:Test of orthogonality of frequency sub- space)。该方法通过同时测试频域信号共同带宽内各频段噪声子空间与阵列流形之间的正交性来进行DOA估计。与宽带相干信号子空...提出了一种新的宽带DOA估计方法:频域子空间正交性测试方法(TOFS:Test of orthogonality of frequency sub- space)。该方法通过同时测试频域信号共同带宽内各频段噪声子空间与阵列流形之间的正交性来进行DOA估计。与宽带相干信号子空间方法不同,TOFS方法不需要任何初始值的预估及聚焦操作。与宽带非相干信号子空间方法也不同,TOFS方法同时测试各频段噪声子空间与阵列流形之间的正交性。本文仿真了TOFS与IMUSIC、CSSM、TOPS的性能比较。仿真结果表明TOFS方法在中等信噪比以上时有较好的性能,且避免了TOPS方法中常出现的伪峰。展开更多
[Objective] This study aimed to establish a multiplex PCR system for de- tecting transgenic ingredients from Citrus. [Method] Based on the pBI121 plasmid sequences published in GenBank and actin gene sequence of Citru...[Objective] This study aimed to establish a multiplex PCR system for de- tecting transgenic ingredients from Citrus. [Method] Based on the pBI121 plasmid sequences published in GenBank and actin gene sequence of Citrus, the primers specific to CaMV35S promoter, NOS promoter, NOS terminator and actin gene were designed, to establish a multiple PCR system which could detect four types of sequences. In addition, orthogonal tests were performed to determine the optimal concentrations of all the components in PCR reaction system, as well as the optimal PCR cycle parameters. [Result] The optimal PCR reaction system should contain 2.5μl of 10xPCR buffer, 2.0μl of MgCI2 （25 mmol/L）, 2.0 μl of dNTP mixture （2.5 mmol/L of each dNTP）, 1.0 μl of actin gene primers （10μmol/L）, 1.0μl of 35S promoter primers （10 μmol/L）, 1.5 μl of NOS promoter primers （10 μmol/L） and 0.5 μl of NOS terminator primers （10μmol/L）, 0.1 μg of template DNA, 1.25 U of Taq DNA polymerase; ddH20 was added to the total reaction system of 25μl. The PCR reaction program consisted of pre-denaturing at 94℃ for 5 min; 31 cycles of denaturing at 94℃ for 30 s, annealing at 64.1℃ for 45 s and extension at 72℃ for 50 s; final extension at 72℃ for 10 min. The reaction system optimized with the orthogonal tests could detect as less as 0.1% transgenic component in the tested samples. [Conclusion] The MPCR detection system established in this study can meet the requirements in theory for detecting the genetically modified ingredients in Citrus or the deep-processed products.展开更多
The influence of factors of the carbon black content, sintering temperature, sintering time, molar ratio of Li to Fe, as well as the electrochemical properties of LiFePO4 for lithium ion battery were studied. The only...The influence of factors of the carbon black content, sintering temperature, sintering time, molar ratio of Li to Fe, as well as the electrochemical properties of LiFePO4 for lithium ion battery were studied. The only technology was obtained by using range analysis through Latin orthogonal experiment of L44（16）. The results show that the optimization synthesis technology of LiFePO4 is content of 5% doping carbon, sintering temperature of 700℃, molar ratio of Li to Fe of 1.03∶1 and sintering time of 16h.The optimized cathode synthesis techniques can make LiFePO4 have good electrochemical properties.展开更多
文摘投影子空间正交性测试法(Test of Orthogonality of Projected Subspaces,TOPS)是利用宽带信号多个频点的子空间的正交性完成波达方向(Direction of Arrival,DOA)估计。该方法依赖参考频率点的选择,易产生伪峰,且在低信噪比时性能差。针对该问题,提出一种聚焦的FTOPS算法。首先利用RCM(Reduced Covariance Matrix)法消除了噪声,然后将各个频点的信号子空间(Signal Subspace)聚焦到任意参考频点的Signal Subspace,利用该参考频点的Signal Subspace与阵列方向矢量的正交投影矩阵之间的正交性完成DOA估计。仿真结果表明,该方法不依赖于参考频点的选择,能有效消除伪峰,在低信噪比条件下性能优于传统TOPS算法。
文摘提出了一种新的宽带DOA估计方法:频域子空间正交性测试方法(TOFS:Test of orthogonality of frequency sub- space)。该方法通过同时测试频域信号共同带宽内各频段噪声子空间与阵列流形之间的正交性来进行DOA估计。与宽带相干信号子空间方法不同,TOFS方法不需要任何初始值的预估及聚焦操作。与宽带非相干信号子空间方法也不同,TOFS方法同时测试各频段噪声子空间与阵列流形之间的正交性。本文仿真了TOFS与IMUSIC、CSSM、TOPS的性能比较。仿真结果表明TOFS方法在中等信噪比以上时有较好的性能,且避免了TOPS方法中常出现的伪峰。
基金Supported by the Special Fund for Key Laboratories of Chongqing (CSTC)National Technology Research and Development Program of Ministry of Science and Technology for Countryside Field (863 Program,2011AA100205)+1 种基金Special Fund for Agro-scientific Research in the Public Interest of Ministry of Agriculture of China(201003067)Key Science and Technology Research Program of Ministry of Education of China (109131)~~
文摘[Objective] This study aimed to establish a multiplex PCR system for de- tecting transgenic ingredients from Citrus. [Method] Based on the pBI121 plasmid sequences published in GenBank and actin gene sequence of Citrus, the primers specific to CaMV35S promoter, NOS promoter, NOS terminator and actin gene were designed, to establish a multiple PCR system which could detect four types of sequences. In addition, orthogonal tests were performed to determine the optimal concentrations of all the components in PCR reaction system, as well as the optimal PCR cycle parameters. [Result] The optimal PCR reaction system should contain 2.5μl of 10xPCR buffer, 2.0μl of MgCI2 （25 mmol/L）, 2.0 μl of dNTP mixture （2.5 mmol/L of each dNTP）, 1.0 μl of actin gene primers （10μmol/L）, 1.0μl of 35S promoter primers （10 μmol/L）, 1.5 μl of NOS promoter primers （10 μmol/L） and 0.5 μl of NOS terminator primers （10μmol/L）, 0.1 μg of template DNA, 1.25 U of Taq DNA polymerase; ddH20 was added to the total reaction system of 25μl. The PCR reaction program consisted of pre-denaturing at 94℃ for 5 min; 31 cycles of denaturing at 94℃ for 30 s, annealing at 64.1℃ for 45 s and extension at 72℃ for 50 s; final extension at 72℃ for 10 min. The reaction system optimized with the orthogonal tests could detect as less as 0.1% transgenic component in the tested samples. [Conclusion] The MPCR detection system established in this study can meet the requirements in theory for detecting the genetically modified ingredients in Citrus or the deep-processed products.
文摘The influence of factors of the carbon black content, sintering temperature, sintering time, molar ratio of Li to Fe, as well as the electrochemical properties of LiFePO4 for lithium ion battery were studied. The only technology was obtained by using range analysis through Latin orthogonal experiment of L44（16）. The results show that the optimization synthesis technology of LiFePO4 is content of 5% doping carbon, sintering temperature of 700℃, molar ratio of Li to Fe of 1.03∶1 and sintering time of 16h.The optimized cathode synthesis techniques can make LiFePO4 have good electrochemical properties.
