提出一种新的聚类预测与动态统计分析方法,融合了集对理论中的同异反(identical different opposeI,DO)不确定性和聚类分析的思想,通过找出最小和最大相似集合,统计每个类别中的最小值和最大值,从而做出相应的决策,并可对不确定值的变...提出一种新的聚类预测与动态统计分析方法,融合了集对理论中的同异反(identical different opposeI,DO)不确定性和聚类分析的思想,通过找出最小和最大相似集合,统计每个类别中的最小值和最大值,从而做出相应的决策,并可对不确定值的变化趋势进行预测,做进一步的估计处理。将该方法应用到“BUS教育”中对学生搭乘“BUS”的人数进行估计、预测和统计,对各个知识模块的学习人数进行统计,并给出最大最小值,从而进行适当的师资配置,并结合《计算机文化基础》教学的实际应用,讨论了这种方法的有效性和实用性。展开更多
α-Diimide catalysts have attracted widespread attention due to their unique chain walking characteristics.A series ofα-diimide nickel/palladium catalysts with different electronic effects and steric hindrances were ...α-Diimide catalysts have attracted widespread attention due to their unique chain walking characteristics.A series ofα-diimide nickel/palladium catalysts with different electronic effects and steric hindrances were designed and synthesized for olefin polymerization.In this work,we synthesized a series of asymmetricα-diimide nickel complexes with different steric hindrances and used them for ethylene polymerization.These nickel catalysts have high ethylene polymerization activity,up to 6.51×10^(6)g·mol^(−1)·h^(−1),and the prepared polyethylene has a moderate melting point and high molecular weight(up to 38.2×10^(4)g·mol^(−1)),with a branching density distribution between 7 and 94 branches per 1000 carbons.More importantly,the polyethylene prepared by these catalysts exhibits excellent tensile properties,with strain and stress reaching 800%and 30 MPa,respectively.展开更多
文摘提出一种新的聚类预测与动态统计分析方法,融合了集对理论中的同异反(identical different opposeI,DO)不确定性和聚类分析的思想,通过找出最小和最大相似集合,统计每个类别中的最小值和最大值,从而做出相应的决策,并可对不确定值的变化趋势进行预测,做进一步的估计处理。将该方法应用到“BUS教育”中对学生搭乘“BUS”的人数进行估计、预测和统计,对各个知识模块的学习人数进行统计,并给出最大最小值,从而进行适当的师资配置,并结合《计算机文化基础》教学的实际应用,讨论了这种方法的有效性和实用性。
基金supported by the National Natural Science Foundation of China(52203016)the USTC Research Funds of the Double First-Class Initiative(YD9990002018)+3 种基金the Overseas Students Innovation and Entrepreneurship Support Program Project of Anhui Province(2021LCX022)the Key R&D Projects in Anhui Province(2022i01020012)the Natural Science Foundation of Hefei(2022039)the Excellent Research and Innovation Team Project of Anhui Province(2022AH010001).
文摘α-Diimide catalysts have attracted widespread attention due to their unique chain walking characteristics.A series ofα-diimide nickel/palladium catalysts with different electronic effects and steric hindrances were designed and synthesized for olefin polymerization.In this work,we synthesized a series of asymmetricα-diimide nickel complexes with different steric hindrances and used them for ethylene polymerization.These nickel catalysts have high ethylene polymerization activity,up to 6.51×10^(6)g·mol^(−1)·h^(−1),and the prepared polyethylene has a moderate melting point and high molecular weight(up to 38.2×10^(4)g·mol^(−1)),with a branching density distribution between 7 and 94 branches per 1000 carbons.More importantly,the polyethylene prepared by these catalysts exhibits excellent tensile properties,with strain and stress reaching 800%and 30 MPa,respectively.