The combination of Morgenstern-Price Method (MPM) with Response Surface Method (RSM) improves the eonventional RSM by replacing Finite-Element Method (FEM) with MPM, which is a type of reliability analysis metho...The combination of Morgenstern-Price Method (MPM) with Response Surface Method (RSM) improves the eonventional RSM by replacing Finite-Element Method (FEM) with MPM, which is a type of reliability analysis method-RSM based on MPM, and makes the computing process simpler. The stability of the slope was re-evaluated by use of Monte Carlo method (MCM) and the result contrasted with the fore is the conclusion. The reliability analysis of the artificial slope in Donggang Power Station was carried on, and obtained the reliable charaeteristics, which provided basis for the project.展开更多
It is better to use a simple configuration to enhance the matched-field inversion method based on a horizontal line applicability of ocean environment inversion in shallow water. A array (HLA) is used to retrieve th...It is better to use a simple configuration to enhance the matched-field inversion method based on a horizontal line applicability of ocean environment inversion in shallow water. A array (HLA) is used to retrieve the variation of sound speed profile. The performance of the inversion method is verified in the South China Sea in June, 2010. An HLA laid at bottom was used to receive signals from a bottom-mounted transducer. Inverted mean sound speed profiles from 9-hour long acoustic signals are in good agreement with measurements from two temperature chains at the sites of the source and receiver. The results show that an HLA can be used to monitor the variability of shallow-water sound speed profile.展开更多
The multiple-path sound propagation in deep water is conducive to source localization of an underwater target.The transmission losses(TLs) and broadband pulse multiple-path propagation characteristics from a deep rece...The multiple-path sound propagation in deep water is conducive to source localization of an underwater target.The transmission losses(TLs) and broadband pulse multiple-path propagation characteristics from a deep receiver is analyzed by using the experimental data from deep water area in the South China Sea(SCS).The results indicate that the width of the direct zone near the bottom of 4300 m water depth is about 30 km.The TLs in the direct zone near the bottom are much less than those in the shadow zone.It is meaningful for underwater sound source detection.Moreover,the time delay between the direct path and the bottomsurface-reflected path for a receiver near the bottom decreases monotonically with the source range.According to the linear relationship between the time delay of multipath and source range,a source localization method is presented to estimate the range of underwater target.The experimental results show that the estimated ranges are consistent with the global position system(GPS) measurements,and the mean square error of the estimation results is less than 0.28 km.展开更多
Four thymine (T) and adenine (A) de- rivatives with pyrene, tetrathiafulvalene and nitronyl nitroxide units (1, 2, 3 and 4) were synthesized and characterized. Fluorescent spectral studies indicate that the correspond...Four thymine (T) and adenine (A) de- rivatives with pyrene, tetrathiafulvalene and nitronyl nitroxide units (1, 2, 3 and 4) were synthesized and characterized. Fluorescent spectral studies indicate that the corresponding T and A derivatives can form ensembles with the association constant of ca. 104 L/mol. The ensemble of 1 and 2 shows pyrene exci- mer emission, while that of 1/3 and 2/4 displays rather weak fluorescence due to the “intramolecular” photoinduced electron transfer reactions. Addition of compounds 5 or 6, which is T and A derivatives, re- spectively, to the ensembles of 1/2, 1/3 and 2/4 re- sults in reduction of excimer emission and en- hancement of pyrene fluorescence. These results show that these ensembles are able to sense T and A molecules.展开更多
文摘The combination of Morgenstern-Price Method (MPM) with Response Surface Method (RSM) improves the eonventional RSM by replacing Finite-Element Method (FEM) with MPM, which is a type of reliability analysis method-RSM based on MPM, and makes the computing process simpler. The stability of the slope was re-evaluated by use of Monte Carlo method (MCM) and the result contrasted with the fore is the conclusion. The reliability analysis of the artificial slope in Donggang Power Station was carried on, and obtained the reliable charaeteristics, which provided basis for the project.
基金supported by the National Natural Science Foundation of China(Grant Nos.11434012,11404366,11125420 and 11074269)
文摘It is better to use a simple configuration to enhance the matched-field inversion method based on a horizontal line applicability of ocean environment inversion in shallow water. A array (HLA) is used to retrieve the variation of sound speed profile. The performance of the inversion method is verified in the South China Sea in June, 2010. An HLA laid at bottom was used to receive signals from a bottom-mounted transducer. Inverted mean sound speed profiles from 9-hour long acoustic signals are in good agreement with measurements from two temperature chains at the sites of the source and receiver. The results show that an HLA can be used to monitor the variability of shallow-water sound speed profile.
基金supported by the National Natural Science Foundation of China(11434012,41561144006)
文摘The multiple-path sound propagation in deep water is conducive to source localization of an underwater target.The transmission losses(TLs) and broadband pulse multiple-path propagation characteristics from a deep receiver is analyzed by using the experimental data from deep water area in the South China Sea(SCS).The results indicate that the width of the direct zone near the bottom of 4300 m water depth is about 30 km.The TLs in the direct zone near the bottom are much less than those in the shadow zone.It is meaningful for underwater sound source detection.Moreover,the time delay between the direct path and the bottomsurface-reflected path for a receiver near the bottom decreases monotonically with the source range.According to the linear relationship between the time delay of multipath and source range,a source localization method is presented to estimate the range of underwater target.The experimental results show that the estimated ranges are consistent with the global position system(GPS) measurements,and the mean square error of the estimation results is less than 0.28 km.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 20421101 and 90501003 )Chinese Academy of Sciences and the National Science Fund for Distinguished Young Scholars (Grant No. 202225207).
文摘Four thymine (T) and adenine (A) de- rivatives with pyrene, tetrathiafulvalene and nitronyl nitroxide units (1, 2, 3 and 4) were synthesized and characterized. Fluorescent spectral studies indicate that the corresponding T and A derivatives can form ensembles with the association constant of ca. 104 L/mol. The ensemble of 1 and 2 shows pyrene exci- mer emission, while that of 1/3 and 2/4 displays rather weak fluorescence due to the “intramolecular” photoinduced electron transfer reactions. Addition of compounds 5 or 6, which is T and A derivatives, re- spectively, to the ensembles of 1/2, 1/3 and 2/4 re- sults in reduction of excimer emission and en- hancement of pyrene fluorescence. These results show that these ensembles are able to sense T and A molecules.