In this paper, a gradient method with momentum for sigma-pi-sigma neural networks (SPSNN) is considered in order to accelerate the convergence of the learning procedure for the network weights. The momentum coefficien...In this paper, a gradient method with momentum for sigma-pi-sigma neural networks (SPSNN) is considered in order to accelerate the convergence of the learning procedure for the network weights. The momentum coefficient is chosen in an adaptive manner, and the corresponding weak convergence and strong convergence results are proved.展开更多
Eric Mazur教授倡导的PI教学理念建立在总结传统教学模式所存在的弊端基础之上,其师生平等对话、生生交流互动的教学方式,不仅能使学生有效参与到教学课程之中,其激励、唤醒、鼓舞的教学方法,对于学生的认知能力、批判精神、创新能力等...Eric Mazur教授倡导的PI教学理念建立在总结传统教学模式所存在的弊端基础之上,其师生平等对话、生生交流互动的教学方式,不仅能使学生有效参与到教学课程之中,其激励、唤醒、鼓舞的教学方法,对于学生的认知能力、批判精神、创新能力等方面的培养也起到了积极的作用。文章正是关于PI教学法植入当前大学英语教学所做的诸多探讨,一是旨在实现教师从"教什么"向"怎样教"的华丽转身,二是为了适应新时期我国高等教育改革的目标。展开更多
Betulin(BE)has exceedingly become a potential natural product,providing multiple pharmacological and biological activi-ties,including anti-cancer,anti-viral,and anti-inflammatory benefits.Previous research indicated t...Betulin(BE)has exceedingly become a potential natural product,providing multiple pharmacological and biological activi-ties,including anti-cancer,anti-viral,and anti-inflammatory benefits.Previous research indicated that the solvatomorphism of BE can easily occur through crystallization with different organic solvents.This property of BE can directly affect its extraction,isolation,and preparation process.In this study,a system of thermogravimetry(TG)-differential thermal analysis(DTA)coupled with mass spectrometry(MS)with electron ionization(EI)and photoionization(PI)capability,equipped with the skimmer-type interface(i.e.,skimmer-type interfaced TG-DTA-EI/PI-MS system),as a real-time and onsite analysis technique,was employed.Then,four solvatomorphs of BE,namely,with pyridine and water(A),sec-butanol(B),n,n-dimethylformamide(DMF)(C),and isopropanol(V),were analyzed for the first time.Finally,five kinds of the main volatile gaseous species,including H2O,pyridine,sec-butanol,DMF,and isopropanol,were identified clearly.Furthermore,the multi-step desolvation processes of the four solvatomorphs of BE were revealed by this system for the first time.This system showed great potential for the rapid and accurate analysis of various solvatomorphs of natural products.展开更多
文摘In this paper, a gradient method with momentum for sigma-pi-sigma neural networks (SPSNN) is considered in order to accelerate the convergence of the learning procedure for the network weights. The momentum coefficient is chosen in an adaptive manner, and the corresponding weak convergence and strong convergence results are proved.
基金supported by National Key R&D Program of China(Grant No.2016YFC1000900)National Science and Technology Major Project of China(Grant Nos.2017ZX09101001003,2018ZX09711001-010)+1 种基金National Natural Science Foundation of China(NSFC)(Grant No.81703473)CAMS Innovation Fund for Medical Sciences(Grant No.2017-I2M-3-010).
文摘Betulin(BE)has exceedingly become a potential natural product,providing multiple pharmacological and biological activi-ties,including anti-cancer,anti-viral,and anti-inflammatory benefits.Previous research indicated that the solvatomorphism of BE can easily occur through crystallization with different organic solvents.This property of BE can directly affect its extraction,isolation,and preparation process.In this study,a system of thermogravimetry(TG)-differential thermal analysis(DTA)coupled with mass spectrometry(MS)with electron ionization(EI)and photoionization(PI)capability,equipped with the skimmer-type interface(i.e.,skimmer-type interfaced TG-DTA-EI/PI-MS system),as a real-time and onsite analysis technique,was employed.Then,four solvatomorphs of BE,namely,with pyridine and water(A),sec-butanol(B),n,n-dimethylformamide(DMF)(C),and isopropanol(V),were analyzed for the first time.Finally,five kinds of the main volatile gaseous species,including H2O,pyridine,sec-butanol,DMF,and isopropanol,were identified clearly.Furthermore,the multi-step desolvation processes of the four solvatomorphs of BE were revealed by this system for the first time.This system showed great potential for the rapid and accurate analysis of various solvatomorphs of natural products.