Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transfo...Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transform domain, we can improve the accuracy and stability of the reconstruction by transforming it to a sparse optimization problem. In this paper, we propose a mathematical model for the sparse reconstruction of data based on the LO-norm minimization. Furthermore, we discuss two types of the approximation algorithm for the LO- norm minimization according to the size and characteristics of the geophysical data: namely, the iteratively reweighted least-squares algorithm and the fast iterative hard thresholding algorithm. Theoretical and numerical analysis showed that applying the iteratively reweighted least-squares algorithm to the reconstruction of potential field data exploits its fast convergence rate, short calculation time, and high precision, whereas the fast iterative hard thresholding algorithm is more suitable for processing seismic data, moreover, its computational efficiency is better than that of the traditional iterative hard thresholding algorithm.展开更多
The biological activity against Staphylococcus aureus, and Eschericia coil were investigated implementing three series, the first series was l-phenyl-2-(4'-X-phenyl)-4-(2,4-dichlorophenyl)-1,3-butadiene, where X ...The biological activity against Staphylococcus aureus, and Eschericia coil were investigated implementing three series, the first series was l-phenyl-2-(4'-X-phenyl)-4-(2,4-dichlorophenyl)-1,3-butadiene, where X = H, CH3, OCH3, NH2, C1, F, NO2 and COOEt; the second was 3,4-dichlorochalcone series namely 3-(3,4-dichlorophenyl)-l-(4'-X-phenyl)-2-propen-l-one, where X = H, CH3, OCH3, NH2, CI, F, NO2 and CN; and the third one was 2,4-dichlorochalcone series namely 3-(2,4-dichlorophenyl)-l- (4'-X-phenyl)-2-propen-l-one, where X = H, CH3, OCH3, NH2, C1, F, NO2 and COOEt. MIC, MBC and the percentage of inhibition (activity) at 20 ~tg/mL, 15 μg/mL and 10μg/mL against Eschericia coli, and at 7.5 lag/mL, 5 μg/mL and 2.5 μg/mL against Staphylococcus aureus, were determined for each compound in the three series. Highest MIC activity against E. coli and S. aureus were given by 2,4-dichlorochalcone series. Butadiene series was similar in behavior to 2,4-dichlorochalcone series in MIC activity against S. aureus. Results of MBC revealed that compounds in the three series exerted high activity against both types of bacteria. Compounds substituted with nitro or nitril exhibited higher activity than other compounds in the three series. Percentage of inhibition of halogenated compounds (4'-C1 and 4'-F) was almost equal in every series. Compounds with substituents (4'-H and 4'-CH3) showed fluctuation in activity according to the nature of each series.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.41074133)
文摘Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transform domain, we can improve the accuracy and stability of the reconstruction by transforming it to a sparse optimization problem. In this paper, we propose a mathematical model for the sparse reconstruction of data based on the LO-norm minimization. Furthermore, we discuss two types of the approximation algorithm for the LO- norm minimization according to the size and characteristics of the geophysical data: namely, the iteratively reweighted least-squares algorithm and the fast iterative hard thresholding algorithm. Theoretical and numerical analysis showed that applying the iteratively reweighted least-squares algorithm to the reconstruction of potential field data exploits its fast convergence rate, short calculation time, and high precision, whereas the fast iterative hard thresholding algorithm is more suitable for processing seismic data, moreover, its computational efficiency is better than that of the traditional iterative hard thresholding algorithm.
文摘The biological activity against Staphylococcus aureus, and Eschericia coil were investigated implementing three series, the first series was l-phenyl-2-(4'-X-phenyl)-4-(2,4-dichlorophenyl)-1,3-butadiene, where X = H, CH3, OCH3, NH2, C1, F, NO2 and COOEt; the second was 3,4-dichlorochalcone series namely 3-(3,4-dichlorophenyl)-l-(4'-X-phenyl)-2-propen-l-one, where X = H, CH3, OCH3, NH2, CI, F, NO2 and CN; and the third one was 2,4-dichlorochalcone series namely 3-(2,4-dichlorophenyl)-l- (4'-X-phenyl)-2-propen-l-one, where X = H, CH3, OCH3, NH2, C1, F, NO2 and COOEt. MIC, MBC and the percentage of inhibition (activity) at 20 ~tg/mL, 15 μg/mL and 10μg/mL against Eschericia coli, and at 7.5 lag/mL, 5 μg/mL and 2.5 μg/mL against Staphylococcus aureus, were determined for each compound in the three series. Highest MIC activity against E. coli and S. aureus were given by 2,4-dichlorochalcone series. Butadiene series was similar in behavior to 2,4-dichlorochalcone series in MIC activity against S. aureus. Results of MBC revealed that compounds in the three series exerted high activity against both types of bacteria. Compounds substituted with nitro or nitril exhibited higher activity than other compounds in the three series. Percentage of inhibition of halogenated compounds (4'-C1 and 4'-F) was almost equal in every series. Compounds with substituents (4'-H and 4'-CH3) showed fluctuation in activity according to the nature of each series.