Herein we summarized some clean preparation examples to emphasize the concept of dual roles design(or named as "two birds one stone strategy") in green and sustainable chemistry.In those examples,the reactan...Herein we summarized some clean preparation examples to emphasize the concept of dual roles design(or named as "two birds one stone strategy") in green and sustainable chemistry.In those examples,the reactants and/or solvent play dual roles rendering a cleaner organic preparation process.Consequently,both the chemical waste and manufacturing cost could be reduced.展开更多
Traditional data envelopment analysis（DEA） theory assumes that decision variables are regarded as inputs or outputs,and no variable can play the roles of both an input and an output at the same time.In fact,there ex...Traditional data envelopment analysis（DEA） theory assumes that decision variables are regarded as inputs or outputs,and no variable can play the roles of both an input and an output at the same time.In fact,there exist some variables that work as inputs and outputs simultaneously and are called dual-role variables.Traditional DEA models cannot be used to appraise the performance of decision making units containing dual-role variables.The paper analyzes the structure and properties of the production systems comprising dual-role variables,and proposes a DEA model integrating dual-role variables.Finally the proposed model is illustrated to evaluate the efficiency of university departments.展开更多
本文选用 1998 年以前上市的所有 A 股公司作为样本,对样本公司的股权特征与董事会领导结构之间的关系进行了研究。研究结果表明:(1)董事长和总经理两职合一模式的公司比例在逐年下降;(2)含有国家股和国家股比例越高的公司越倾向于总经...本文选用 1998 年以前上市的所有 A 股公司作为样本,对样本公司的股权特征与董事会领导结构之间的关系进行了研究。研究结果表明:(1)董事长和总经理两职合一模式的公司比例在逐年下降;(2)含有国家股和国家股比例越高的公司越倾向于总经理和董事长两个职位由同一个人担任;(3)由母公司控股以及中央和部委所属的公司更倾向于由大股东董事长同时担任上市公司董事长;(4)控股股东持股比例越高,控股股东董事长担任上市公司董事长的可能性就越大。展开更多
基金financial support from the National Natural Science Foundation of China(Nos.21545010 and 31527803)Hunan Provincial Natural Science Foundation of China(No. 2019JJ20008)
文摘Herein we summarized some clean preparation examples to emphasize the concept of dual roles design(or named as "two birds one stone strategy") in green and sustainable chemistry.In those examples,the reactants and/or solvent play dual roles rendering a cleaner organic preparation process.Consequently,both the chemical waste and manufacturing cost could be reduced.
基金supported by the National Natural Science Foundation of China (7082100170801056)
文摘Traditional data envelopment analysis（DEA） theory assumes that decision variables are regarded as inputs or outputs,and no variable can play the roles of both an input and an output at the same time.In fact,there exist some variables that work as inputs and outputs simultaneously and are called dual-role variables.Traditional DEA models cannot be used to appraise the performance of decision making units containing dual-role variables.The paper analyzes the structure and properties of the production systems comprising dual-role variables,and proposes a DEA model integrating dual-role variables.Finally the proposed model is illustrated to evaluate the efficiency of university departments.
文摘本文选用 1998 年以前上市的所有 A 股公司作为样本,对样本公司的股权特征与董事会领导结构之间的关系进行了研究。研究结果表明:(1)董事长和总经理两职合一模式的公司比例在逐年下降;(2)含有国家股和国家股比例越高的公司越倾向于总经理和董事长两个职位由同一个人担任;(3)由母公司控股以及中央和部委所属的公司更倾向于由大股东董事长同时担任上市公司董事长;(4)控股股东持股比例越高,控股股东董事长担任上市公司董事长的可能性就越大。
