针对已有多任务优化算法寻优精度受限、计算时间成本过高等问题,提出一种基于改进灰狼算法的多任务优化算法(improved grey wolf algorithm based multitask optimization algorithm,IGWMTO)。该算法采用灰狼算法代替典型多任务算法中...针对已有多任务优化算法寻优精度受限、计算时间成本过高等问题,提出一种基于改进灰狼算法的多任务优化算法(improved grey wolf algorithm based multitask optimization algorithm,IGWMTO)。该算法采用灰狼算法代替典型多任务算法中的遗传算法,计算个体的因素等级和技能因子实现狼群分类,并以此更新个体隶属任务,引入扰动因子和动态权重改善狼群个体的更新方式。仿真测试结果表明:相比于传统多任务优化算法,所提算法在4个优化问题上的寻优精度的提升均超过了4.8%,计算耗时降低了70%以上。展开更多
The corrosion of ECR glass fiber was investigated by the analysis methods of weight loss ratio under different acids and at various durations.Weight loss,leaching of cations,and surface composition of ECR glass fiber ...The corrosion of ECR glass fiber was investigated by the analysis methods of weight loss ratio under different acids and at various durations.Weight loss,leaching of cations,and surface composition of ECR glass fiber were analyzed.The corrosion mechanism of ECR glass fiber in acid environment was also discussed.The experimental results showed that the corrosion degree of ECR glass fiber in different acids obeyed the order： HNO3〉H2SO4〉HCl.The acid effects on corrosion of ECR glass fiberis were totally different.Hydrochloric acid mainly destroyed the network structure of [AlO4],while sulfuric acid and nitric acid mainly destroyed the structure of [SiO4].The acid resistance of ECR glass fiber is much better than that of E glass fiber due to the generation of intermediate product silicic acid gel Si（OH）4 during ion exchange.It can adhere to the glass surface to form a thin film and hinder the proceeding of corrosion.展开更多
The efficiencies of 6 kinds of macromolecules with dendritic structure in improving the flow properties of crude oil were investigated. The dendritic additives were synthesized using low-generation dendritic poly(amid...The efficiencies of 6 kinds of macromolecules with dendritic structure in improving the flow properties of crude oil were investigated. The dendritic additives were synthesized using low-generation dendritic poly(amidoamine) and alkyl longchain acrylic esters as starting materials, and their structures were characterized by the Fourier transform infrared spectroscopy, 1H-nuclear magnetic resonance and elemental analysis. The effects on the pour point and rheological properties of crude oil samples were studied. Efficiencies of dendritic long-chain esters were not only influenced by the alky chain length, but also by the generation of dendrimer. The longer the alkyl chain of dendritic long-chain ester was, the better the effect in the reduction of pour point and apparent viscosity was. Efficiencies of 1.5 generation dendritic long-chain ester with 8 branched chains for the reduction of pour point and apparent viscosity were superior to those of 0.5 generation dendritic long-chain ester with 4 branched chains. Under the same conditions, efficiencies of 1.5 generation dendritic eighteen ester were superior to those of other 1.5 generation dendritic long-chain esters for the reduction of pour point and viscosity of crude oil.展开更多
文摘针对已有多任务优化算法寻优精度受限、计算时间成本过高等问题,提出一种基于改进灰狼算法的多任务优化算法(improved grey wolf algorithm based multitask optimization algorithm,IGWMTO)。该算法采用灰狼算法代替典型多任务算法中的遗传算法,计算个体的因素等级和技能因子实现狼群分类,并以此更新个体隶属任务,引入扰动因子和动态权重改善狼群个体的更新方式。仿真测试结果表明:相比于传统多任务优化算法,所提算法在4个优化问题上的寻优精度的提升均超过了4.8%,计算耗时降低了70%以上。
基金Funded by the National Natural Science Foundation of China(No.51472191)the Wuhan City Chenguang Project(No.2014070404010208)+2 种基金the Natural Science Foundation of Hubei Province(Nos.2014CFB343 and 2014CFB859)the Doctoral Program of Higher Education(No.20130143110013)the Key Technology Innovation Project of Hubei Province(No.2013AAA017)
文摘The corrosion of ECR glass fiber was investigated by the analysis methods of weight loss ratio under different acids and at various durations.Weight loss,leaching of cations,and surface composition of ECR glass fiber were analyzed.The corrosion mechanism of ECR glass fiber in acid environment was also discussed.The experimental results showed that the corrosion degree of ECR glass fiber in different acids obeyed the order： HNO3〉H2SO4〉HCl.The acid effects on corrosion of ECR glass fiberis were totally different.Hydrochloric acid mainly destroyed the network structure of [AlO4],while sulfuric acid and nitric acid mainly destroyed the structure of [SiO4].The acid resistance of ECR glass fiber is much better than that of E glass fiber due to the generation of intermediate product silicic acid gel Si（OH）4 during ion exchange.It can adhere to the glass surface to form a thin film and hinder the proceeding of corrosion.
基金supported financially by the Heilongjiang Postdoctorial Financial Foundation of China (Project NO. LBH-Zo8290)The Daqing Oil Field of China was thanked for providing the financial support and the crude oil
文摘The efficiencies of 6 kinds of macromolecules with dendritic structure in improving the flow properties of crude oil were investigated. The dendritic additives were synthesized using low-generation dendritic poly(amidoamine) and alkyl longchain acrylic esters as starting materials, and their structures were characterized by the Fourier transform infrared spectroscopy, 1H-nuclear magnetic resonance and elemental analysis. The effects on the pour point and rheological properties of crude oil samples were studied. Efficiencies of dendritic long-chain esters were not only influenced by the alky chain length, but also by the generation of dendrimer. The longer the alkyl chain of dendritic long-chain ester was, the better the effect in the reduction of pour point and apparent viscosity was. Efficiencies of 1.5 generation dendritic long-chain ester with 8 branched chains for the reduction of pour point and apparent viscosity were superior to those of 0.5 generation dendritic long-chain ester with 4 branched chains. Under the same conditions, efficiencies of 1.5 generation dendritic eighteen ester were superior to those of other 1.5 generation dendritic long-chain esters for the reduction of pour point and viscosity of crude oil.
