Based on the constrained total least squares （CTLS） passive location algorithm with bearing-only measurements, in this paper, the same passive location problem is transformed into the structured total least squares ...Based on the constrained total least squares （CTLS） passive location algorithm with bearing-only measurements, in this paper, the same passive location problem is transformed into the structured total least squares （STLS） problem.The solution of the STLS problem for passive location can be obtained using the inverse iteration method.It also expatiates that both the STLS algorithm and the CTLS algorithm have the same location mean squares error under certain condition.Finally, the article presents a kind of location and tracking algorithm for moving target by combining STLS location algorithm with Kalman filter （KF）.The efficiency and superiority of the proposed algorithms can be confirmed by computer simulation results.展开更多
In the present study, we aimed to intensively study the chemical constituents, especially organic acids from a medicinal plant Portulaca oleracea L., and screen their anti-inflammatory and quinone reductase （QR, a ph...In the present study, we aimed to intensively study the chemical constituents, especially organic acids from a medicinal plant Portulaca oleracea L., and screen their anti-inflammatory and quinone reductase （QR, a phase II detoxyfication enzyme） inductive activity. A total of 20 compounds were isolated and identified based on spectroscopic methods, as succinic acid （1）, mono-methyl succinate （2）, L-malic acid （3）, L-l-methyl malate （4）, L-4-methyl malate （5）, L-dimethyl malate （6）, L-6-ethyl citrate （7）, L-1-methyl citrate （8）, L-1,5-dimethyl citrate （9）, 4-hydroxy-5-methylfuran-3-carboxylic acid （10）, 5-hydroxymethyl-furoic acid （11）, stearic acid （12）, L-pyroglutamic acid （13）, cyclo-（tyrosine-leucine） （14）, L-isoleucine （15）, （-）-dehydrovomifoliol （16）, （-）-epiloliolide （17）, 3,4-dihydroxyphenylethanol （18）, succinimide （19）, and uracil （20）. Among them, 14 compounds （2, 4-8, 10, 11, 13-18） were isolated from P. oleracea for the first time. Compotmd 18 （12.5 μM） exhibited potent anti-inflammatory effect in lipopolysaccharide （LPS）-induced macrophage cells （RAW264.7） by reducing NO production, and it also increased QR activity in Hepa lclc7 cells. Compound 16 （50 μM） showed weak QR inductive activity. None of other compounds showed anti-inflammatory or QR inductive activities.展开更多
In order to protect copyright of digital images,a new robust digital image watermarking algorithm based on chaotic system and QR factorization was proposed.The host images were firstly divided into blocks with same si...In order to protect copyright of digital images,a new robust digital image watermarking algorithm based on chaotic system and QR factorization was proposed.The host images were firstly divided into blocks with same size,then QR factorization was performed on each block.Pseudorandom circular chain(PCC) generated by logistic mapping(LM) was applied to select the embedding blocks for enhancing the security of the scheme.The first column coefficients in Q matrix of chosen blocks were modified to embed watermarks without causing noticeable artifacts.Watermark extraction procedure was performed without the original cover image.The experimental results demonstrate that the watermarked images have good visual quality and this scheme is better than the existing techniques,especially when the image is attacked by cropping,noise pollution and so on.Analysis and discussion on robustness and security issues were also presented.展开更多
针对多输入多输出系统中常用的非线性检测算法,如排序QR分解(Sorted QR Decomposition,SQRD)、球型译码(Sphere Decoding,SD)、K-Best或QRM(QR Decomposition and M algorithm)等,提出了一种具有最优检测顺序的QR快速分解方法,作为检测...针对多输入多输出系统中常用的非线性检测算法,如排序QR分解(Sorted QR Decomposition,SQRD)、球型译码(Sphere Decoding,SD)、K-Best或QRM(QR Decomposition and M algorithm)等,提出了一种具有最优检测顺序的QR快速分解方法,作为检测前的预处理操作。该算法首先对信道矩阵进行第一次QR分解,根据所得上三角矩阵R可确定最优的检测顺序,并按该顺序对R进行列重排。然后对R进行第二次QR分解,即得具有最优检测顺序的QR分解结果。与现有的基于R对角元素的模值排序的QR分解算法相比,本算法可保证检测顺序最优从而性能最优。仿真结果表明天线配置为4×4和6×6时,在误码率10^(-3)处可节约信噪比分别为:1dB和2dB;与现有的基于信干噪比排序的QR分解算法相比,本算法与其性能一致的基础上可节约25%的复乘法次数和33%的复加法次数。展开更多
文摘Based on the constrained total least squares （CTLS） passive location algorithm with bearing-only measurements, in this paper, the same passive location problem is transformed into the structured total least squares （STLS） problem.The solution of the STLS problem for passive location can be obtained using the inverse iteration method.It also expatiates that both the STLS algorithm and the CTLS algorithm have the same location mean squares error under certain condition.Finally, the article presents a kind of location and tracking algorithm for moving target by combining STLS location algorithm with Kalman filter （KF）.The efficiency and superiority of the proposed algorithms can be confirmed by computer simulation results.
基金National Natural Science Foundation of China(Grant No.81073005)Science and Technology Development Program of Shandong Province(Grant No.2014GSF119007)+2 种基金Major Project of Science and Technology of Shandong Province(Grant No.2015ZDJS04001)Young Scholars Program of Shandong University(Grant No.YSPSDU2015WLJH50)China-Australia Centre for Health Sciences Research(2015)
文摘In the present study, we aimed to intensively study the chemical constituents, especially organic acids from a medicinal plant Portulaca oleracea L., and screen their anti-inflammatory and quinone reductase （QR, a phase II detoxyfication enzyme） inductive activity. A total of 20 compounds were isolated and identified based on spectroscopic methods, as succinic acid （1）, mono-methyl succinate （2）, L-malic acid （3）, L-l-methyl malate （4）, L-4-methyl malate （5）, L-dimethyl malate （6）, L-6-ethyl citrate （7）, L-1-methyl citrate （8）, L-1,5-dimethyl citrate （9）, 4-hydroxy-5-methylfuran-3-carboxylic acid （10）, 5-hydroxymethyl-furoic acid （11）, stearic acid （12）, L-pyroglutamic acid （13）, cyclo-（tyrosine-leucine） （14）, L-isoleucine （15）, （-）-dehydrovomifoliol （16）, （-）-epiloliolide （17）, 3,4-dihydroxyphenylethanol （18）, succinimide （19）, and uracil （20）. Among them, 14 compounds （2, 4-8, 10, 11, 13-18） were isolated from P. oleracea for the first time. Compotmd 18 （12.5 μM） exhibited potent anti-inflammatory effect in lipopolysaccharide （LPS）-induced macrophage cells （RAW264.7） by reducing NO production, and it also increased QR activity in Hepa lclc7 cells. Compound 16 （50 μM） showed weak QR inductive activity. None of other compounds showed anti-inflammatory or QR inductive activities.
基金Project(2007AA01Z241-2) supported by the National High-tech Research and Development Program of ChinaProject(2006XM002) supported by Beijing Jiaotong University Science Foundation,ChinaProject(0910KYZY55) supported by the Fundamental Research Funds for the Central University in China
文摘In order to protect copyright of digital images,a new robust digital image watermarking algorithm based on chaotic system and QR factorization was proposed.The host images were firstly divided into blocks with same size,then QR factorization was performed on each block.Pseudorandom circular chain(PCC) generated by logistic mapping(LM) was applied to select the embedding blocks for enhancing the security of the scheme.The first column coefficients in Q matrix of chosen blocks were modified to embed watermarks without causing noticeable artifacts.Watermark extraction procedure was performed without the original cover image.The experimental results demonstrate that the watermarked images have good visual quality and this scheme is better than the existing techniques,especially when the image is attacked by cropping,noise pollution and so on.Analysis and discussion on robustness and security issues were also presented.
文摘针对多输入多输出系统中常用的非线性检测算法,如排序QR分解(Sorted QR Decomposition,SQRD)、球型译码(Sphere Decoding,SD)、K-Best或QRM(QR Decomposition and M algorithm)等,提出了一种具有最优检测顺序的QR快速分解方法,作为检测前的预处理操作。该算法首先对信道矩阵进行第一次QR分解,根据所得上三角矩阵R可确定最优的检测顺序,并按该顺序对R进行列重排。然后对R进行第二次QR分解,即得具有最优检测顺序的QR分解结果。与现有的基于R对角元素的模值排序的QR分解算法相比,本算法可保证检测顺序最优从而性能最优。仿真结果表明天线配置为4×4和6×6时,在误码率10^(-3)处可节约信噪比分别为:1dB和2dB;与现有的基于信干噪比排序的QR分解算法相比,本算法与其性能一致的基础上可节约25%的复乘法次数和33%的复加法次数。
