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Optimization of Shanghai marine environment monitoring sites by integrating spatial correlation and stratified heterogeneity 被引量:2
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作者 FAN Haimei GAO Bingbo +1 位作者 XU Ren WANG Jinfeng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第2期111-121,共11页
The water quality grades of phosphate(PO4-P) and dissolved inorganic nitrogen(DIN) are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validat... The water quality grades of phosphate(PO4-P) and dissolved inorganic nitrogen(DIN) are integrated by spatial partitioning to fit the global and local semi-variograms of these nutrients. Leave-one-out cross validation is used to determine the statistical inference method. To minimize absolute average errors and error mean squares,stratified Kriging(SK) interpolation is applied to DIN and ordinary Kriging(OK) interpolation is applied to PO4-P.Ten percent of the sites is adjusted by considering their impact on the change in deviations in DIN and PO4-P interpolation and the resultant effect on areas with different water quality grades. Thus, seven redundant historical sites are removed. Seven historical sites are distributed in areas with water quality poorer than Grade IV at the north and south branches of the Changjiang(Yangtze River) Estuary and at the coastal region north of the Hangzhou Bay. Numerous sites are installed in these regions. The contents of various elements in the waters are not remarkably changed, and the waters are mixed well. Seven sites that have been optimized and removed are set to water with quality Grades III and IV. Optimization and adjustment of unrestricted areas show that the optimized and adjusted sites are mainly distributed in regions where the water quality grade undergoes transition.Therefore, key sites for adjustment and optimization are located at the boundaries of areas with different water quality grades and seawater. 展开更多
关键词 area of water quality grade stratified Kriging(SK) leave-one-out cross validation method spatial simulated annealing method monitoring sites optimization
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Reliability Sensitivity Algorithm Based on Stratified Importance Sampling Method for Multiple Failure Modes Systems 被引量:8
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作者 Zhang Feng Lu Zhenzhou +1 位作者 Cui Lijie Song Shufang 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第6期660-669,共10页
Combining the advantages of the stratified sampling and the importance sampling, a stratified importance sampling method (SISM) is presented to analyze the reliability sensitivity for structure with multiple failure... Combining the advantages of the stratified sampling and the importance sampling, a stratified importance sampling method (SISM) is presented to analyze the reliability sensitivity for structure with multiple failure modes. In the presented method, the variable space is divided into several disjoint subspace by n-dimensional coordinate planes at the mean point of the random vec- tor, and the importance sampling functions in the subspaces are constructed by keeping the sampling center at the mean point and augmenting the standard deviation by a factor of 2. The sample size generated from the importance sampling function in each subspace is determined by the contribution of the subspace to the reliability sensitivity, which can be estimated by iterative simulation in the sampling process. The formulae of the reliability sensitivity estimation, the variance and the coefficient of variation are derived for the presented SISM. Comparing with the Monte Carlo method, the stratified sampling method and the importance sampling method, the presented SISM has wider applicability and higher calculation efficiency, which is demonstrated by numerical examples. Finally, the reliability sensitivity analysis of flap structure is illustrated that the SISM can be applied to engineering structure. 展开更多
关键词 multiple failure modes reliability sensitivity Monte Carlo simulation stratified sampling method importance sam-piing method stratified importance sampling method (SISM)
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Exploration of Stratified Evidence Scoring Method of Acupuncture Clinical Practice Guidelines 被引量:5
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作者 LYU Zhong-xi ZHAO Xue +3 位作者 GUO Yi CHEN Ze-lin WANG Shen-jun GONG Yi-nan 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2021年第2期141-147,共7页
Due to its own internal laws of development,Chinese medicine(CM)seems more inclined to empirical medicine in a relatively long historical period.It is considered to be lacking objective and unified clinical practice g... Due to its own internal laws of development,Chinese medicine(CM)seems more inclined to empirical medicine in a relatively long historical period.It is considered to be lacking objective and unified clinical practice guidelines(CPGs),and the difficulties in diagnosis and therapeutic effect evaluation comes with it,have restricted its further inheritance,development and international communication.Over the years,our research group has been committed to improving the standardization theory and methodology of CM,also perfecting relative techniques for further application,which are all based on the stratified evidence scoring method.We have already applied this method to 45 issued guidelines,including 5 national guidelines,3 industrial guidelines,and 37 formulation/revision social organization guidelines.The stratified evidence scoring method has been recognized and used widely.It helps scholars and applicators to study,formulate,publish and popularize the acupuncture therapy clinical practice guidelines better,thus further promotes the development of acupuncture therapy. 展开更多
关键词 Chinese medicine stratified evidence scoring method acupuncture clinical practice guideline EVIDENCE ancient literature modern literature medical experience of modern famous physicians
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