Long tree-ring chronologies can be developed by overlapping data from living trees with data from fossil trees through cross-dating.However,low-frequency climate signals are lost when standardizing tree-ring series du...Long tree-ring chronologies can be developed by overlapping data from living trees with data from fossil trees through cross-dating.However,low-frequency climate signals are lost when standardizing tree-ring series due to the"segment length curse".To alleviate the segment length curse and thus improve the standardization method for developing long tree-ring chronologies,here we first calculated a mean value for all the tree ring series by overlapping all of the tree ring series.The growth trend of the mean tree ring width(i.e.,cumulated average growth trend of all the series)was determined using ensemble empirical mode decomposition.Then the chronology was developed by dividing the mean value by the growth trend of the mean value.Our improved method alleviated the problem of trend distortion.Long-term signals were better preserved using the improved method than in previous detrending methods.The chronologies developed using the improved method were better correlated with climate than those developed using conservative methods.The improved standardization method alleviates trend distortion and retains more of the low-frequency climate signals.展开更多
The matters of equipment optimization development are usually discrete,fuzzy and non-quantitative.It is difficult directly to optimize the equipment development with a mathematical model.A set of methods for designing...The matters of equipment optimization development are usually discrete,fuzzy and non-quantitative.It is difficult directly to optimize the equipment development with a mathematical model.A set of methods for designing the equipment optimization development with six dimensions and eight main elements is established based on the theory and method of standardization.The top-tier design space of systematic development of equipment is built up by the relations of basic models,series and model spectrums.The relations of time and space for equipment optimization development are established.The design processes of a six dimension systematic space are expounded.The connotation of each plan in the main system space is analyzed.A design method for an entire equipment is established with standardization theory.The coordinating design methods of equipment technical system and the optimization design methods of equipment integration are discussed.The design methods for universalization and serialization of components and parts are established.The design methods of equipment optimization development highlight the relations of the basic model of platform,the serialization of platform basic models,the modularization of equipment functions,the model spectrum of variant equipment,and the universalization and serialization of components and parts.展开更多
目的探讨案例学习(case-based learning,CBL)-问题学习(problem-based learning,PBL)-循证医学(evidence-based medicine,EBM)整合教学法在肾脏内科住院医师规范化培训中的应用效果。方法选取2023年2月1日—8月31日期间于肾脏内科轮转...目的探讨案例学习(case-based learning,CBL)-问题学习(problem-based learning,PBL)-循证医学(evidence-based medicine,EBM)整合教学法在肾脏内科住院医师规范化培训中的应用效果。方法选取2023年2月1日—8月31日期间于肾脏内科轮转时间为2个月的60名内科规培医师,按照1∶1比例随机分为试验组(CBL-PBL-EBM组)和对照组(CBL组)。对比分析两组规培医师轮转结束时的理论考试、病案分析、综合能力评分。结果试验组与对照组理论考核成绩差异无统计学意义(45.21±3.67 vs 44.02±4.90,P>0.05)。试验组病案分析考核成绩高于对照组(42.48±2.35 vs 38.45±3.24,P<0.05),综合评分高于对照组(92.24±1.69 vs 89.21±1.56,P<0.05),同时试验组在自主学习、文献查询能力、批判性思维、归纳总结能力方面的评分也明显优于对照组,差异有统计学意义(P<0.05)。结论CBL-PBL-EBM整合教学法在教学效果上总体优于CBL教学法,能够有效实现规培目标,并促进肾脏内科规培医师综合素质的提升。展开更多
文摘Long tree-ring chronologies can be developed by overlapping data from living trees with data from fossil trees through cross-dating.However,low-frequency climate signals are lost when standardizing tree-ring series due to the"segment length curse".To alleviate the segment length curse and thus improve the standardization method for developing long tree-ring chronologies,here we first calculated a mean value for all the tree ring series by overlapping all of the tree ring series.The growth trend of the mean tree ring width(i.e.,cumulated average growth trend of all the series)was determined using ensemble empirical mode decomposition.Then the chronology was developed by dividing the mean value by the growth trend of the mean value.Our improved method alleviated the problem of trend distortion.Long-term signals were better preserved using the improved method than in previous detrending methods.The chronologies developed using the improved method were better correlated with climate than those developed using conservative methods.The improved standardization method alleviates trend distortion and retains more of the low-frequency climate signals.
文摘The matters of equipment optimization development are usually discrete,fuzzy and non-quantitative.It is difficult directly to optimize the equipment development with a mathematical model.A set of methods for designing the equipment optimization development with six dimensions and eight main elements is established based on the theory and method of standardization.The top-tier design space of systematic development of equipment is built up by the relations of basic models,series and model spectrums.The relations of time and space for equipment optimization development are established.The design processes of a six dimension systematic space are expounded.The connotation of each plan in the main system space is analyzed.A design method for an entire equipment is established with standardization theory.The coordinating design methods of equipment technical system and the optimization design methods of equipment integration are discussed.The design methods for universalization and serialization of components and parts are established.The design methods of equipment optimization development highlight the relations of the basic model of platform,the serialization of platform basic models,the modularization of equipment functions,the model spectrum of variant equipment,and the universalization and serialization of components and parts.
文摘目的探讨案例学习(case-based learning,CBL)-问题学习(problem-based learning,PBL)-循证医学(evidence-based medicine,EBM)整合教学法在肾脏内科住院医师规范化培训中的应用效果。方法选取2023年2月1日—8月31日期间于肾脏内科轮转时间为2个月的60名内科规培医师,按照1∶1比例随机分为试验组(CBL-PBL-EBM组)和对照组(CBL组)。对比分析两组规培医师轮转结束时的理论考试、病案分析、综合能力评分。结果试验组与对照组理论考核成绩差异无统计学意义(45.21±3.67 vs 44.02±4.90,P>0.05)。试验组病案分析考核成绩高于对照组(42.48±2.35 vs 38.45±3.24,P<0.05),综合评分高于对照组(92.24±1.69 vs 89.21±1.56,P<0.05),同时试验组在自主学习、文献查询能力、批判性思维、归纳总结能力方面的评分也明显优于对照组,差异有统计学意义(P<0.05)。结论CBL-PBL-EBM整合教学法在教学效果上总体优于CBL教学法,能够有效实现规培目标,并促进肾脏内科规培医师综合素质的提升。
