Steel-concrete composite structures(SCCS)have been widely used as primary load-bearing components in large-scale civil infrastructures.As the basis of the co-working ability of steel plate and concrete,the bonding sta...Steel-concrete composite structures(SCCS)have been widely used as primary load-bearing components in large-scale civil infrastructures.As the basis of the co-working ability of steel plate and concrete,the bonding status plays an essential role in guaranteeing the structural performance of SCCS.Accordingly,efficient non-destructive testing(NDT)on interfacial debondings in SCCS has become a prominent research area.Multi-channel analysis of surface waves(MASW)has been validated as an effective NDT technique for interfacial debonding detection for SCCS.However,the feasibility of MASW must be validated using experimental measurements.This study establishes a high-frequency data synchronous acquisition system with 32 channels to perform comparative verification experiments in depth.First,the current sensing approaches for high-frequency vibration and stress waves are summarized.Secondly,three types of contact sensors,namely,piezoelectric lead-zirconate-titanate(PZT)patches,accelerometers,and ultrasonic transducers,are selected for MASW measurement.Then,the selection and optimization of the force hammer head are performed.Comparative experiments are carried out for the optimal selection of ultrasonic transducers,PZT patches,and accelerometers for MASW measurement.In addition,the influence of different pasting methods on the output signal of the sensor array is discussed.Experimental results indicate that optimized PZT patches,acceleration sensors,and ultrasonic transducers can provide efficient data acquisition for MASW-based non-destructive experiments.The research findings in this study lay a solid foundation for analyzing the recognition accuracy of contact MASW measurement using different sensor arrays.展开更多
2015年11月6-8日,学生保护科学大会（Student Conference on Conservation Sciences,SCCS）北京分会在北京大学召开.SCCS由英国剑桥大学于2000年创立,是世界上为数不多的以学生和年轻人为主角的保护科学年会.首次SCCS会议在剑桥大学举行...2015年11月6-8日,学生保护科学大会（Student Conference on Conservation Sciences,SCCS）北京分会在北京大学召开.SCCS由英国剑桥大学于2000年创立,是世界上为数不多的以学生和年轻人为主角的保护科学年会.首次SCCS会议在剑桥大学举行,目前已经发展了北京、班加罗尔、纽约和布里斯班4个分会场.展开更多
李约瑟(Joseph Needham,1900年12月9日-1995年3月24日),出生于英国伦敦,英国剑桥李约瑟研究所第一任所长,中国科学院外籍院士,中国人民的老朋友。他为中国人所熟悉的就是著名的“李约瑟之问”,以及诞生这一世纪之问的七卷本近三十册煌...李约瑟(Joseph Needham,1900年12月9日-1995年3月24日),出生于英国伦敦,英国剑桥李约瑟研究所第一任所长,中国科学院外籍院士,中国人民的老朋友。他为中国人所熟悉的就是著名的“李约瑟之问”,以及诞生这一世纪之问的七卷本近三十册煌煌巨著《中国科学技术史》(Science and Civilisation in China,SCC)。展开更多
The Chinese government promotes smoking cessation through smoking cessation clinics(SCCs).This study aimed to identify factors associated with relapse and provide evidence to inform interventions that reduce relapse r...The Chinese government promotes smoking cessation through smoking cessation clinics(SCCs).This study aimed to identify factors associated with relapse and provide evidence to inform interventions that reduce relapse risk.Participants were SCC patients aged≥18 years who enrolled between June 2019 and December 2021,completed follow-up assessments at one and three months,and reported abstinence at one month.Short-term relapse was defined as self-reported smoking at the three-month follow-up.Treatments included counseling,first-line cessation medications,and traditional Chinese medicine(TCM).Logistic regression was used to identify factors associated with short-term relapse.Among 10,724 eligible SCC patients,11.6%experienced short-term relapse.Factors positively associated with relapse included the number of previous quit attempts(1–5 attempts:OR=1.422,95%CI:1.254–1.613,>5 attempts:OR=1.382,95%CI:1.057–1.808),high perceived difficulty in quitting(OR=1.297,95%CI:1.061–1.586),and moderate(OR=1.383,95%CI:1.174–1.629)or weak(OR=1.517,95%CI:1.251–1.841)willingness to quit.Factors negatively associated with relapse included having a college degree or higher(OR=0.796;95%CI:0.650–0.973),high confidence in quitting(OR=0.786;95%CI:0.629–0.983),and use of TCM(OR=0.276;95%CI:0.158–0.482).Enhancing self-efficacy in quitting appears crucial for preventing short-term relapse.The use of TCM may reduce relapse risk and warrants further investigation.展开更多
基金National Natural Science Foundation of China under Grant (Nos.52192662,52020105005,51908320)the Beijing Nova Program under Grant No.20220484012+1 种基金the Interdisciplinary Research Project for Young Teachers of USTB (Fundamental Research Funds for the Central Universities,FRF-IDRY-22-013)the Key Laboratory for Intelligent Infrastructure and Monitoring of Fujian Province (Huaqiao University,IIM-01-05)。
文摘Steel-concrete composite structures(SCCS)have been widely used as primary load-bearing components in large-scale civil infrastructures.As the basis of the co-working ability of steel plate and concrete,the bonding status plays an essential role in guaranteeing the structural performance of SCCS.Accordingly,efficient non-destructive testing(NDT)on interfacial debondings in SCCS has become a prominent research area.Multi-channel analysis of surface waves(MASW)has been validated as an effective NDT technique for interfacial debonding detection for SCCS.However,the feasibility of MASW must be validated using experimental measurements.This study establishes a high-frequency data synchronous acquisition system with 32 channels to perform comparative verification experiments in depth.First,the current sensing approaches for high-frequency vibration and stress waves are summarized.Secondly,three types of contact sensors,namely,piezoelectric lead-zirconate-titanate(PZT)patches,accelerometers,and ultrasonic transducers,are selected for MASW measurement.Then,the selection and optimization of the force hammer head are performed.Comparative experiments are carried out for the optimal selection of ultrasonic transducers,PZT patches,and accelerometers for MASW measurement.In addition,the influence of different pasting methods on the output signal of the sensor array is discussed.Experimental results indicate that optimized PZT patches,acceleration sensors,and ultrasonic transducers can provide efficient data acquisition for MASW-based non-destructive experiments.The research findings in this study lay a solid foundation for analyzing the recognition accuracy of contact MASW measurement using different sensor arrays.
文摘2015年11月6-8日,学生保护科学大会（Student Conference on Conservation Sciences,SCCS）北京分会在北京大学召开.SCCS由英国剑桥大学于2000年创立,是世界上为数不多的以学生和年轻人为主角的保护科学年会.首次SCCS会议在剑桥大学举行,目前已经发展了北京、班加罗尔、纽约和布里斯班4个分会场.
文摘李约瑟(Joseph Needham,1900年12月9日-1995年3月24日),出生于英国伦敦,英国剑桥李约瑟研究所第一任所长,中国科学院外籍院士,中国人民的老朋友。他为中国人所熟悉的就是著名的“李约瑟之问”,以及诞生这一世纪之问的七卷本近三十册煌煌巨著《中国科学技术史》(Science and Civilisation in China,SCC)。
文摘The Chinese government promotes smoking cessation through smoking cessation clinics(SCCs).This study aimed to identify factors associated with relapse and provide evidence to inform interventions that reduce relapse risk.Participants were SCC patients aged≥18 years who enrolled between June 2019 and December 2021,completed follow-up assessments at one and three months,and reported abstinence at one month.Short-term relapse was defined as self-reported smoking at the three-month follow-up.Treatments included counseling,first-line cessation medications,and traditional Chinese medicine(TCM).Logistic regression was used to identify factors associated with short-term relapse.Among 10,724 eligible SCC patients,11.6%experienced short-term relapse.Factors positively associated with relapse included the number of previous quit attempts(1–5 attempts:OR=1.422,95%CI:1.254–1.613,>5 attempts:OR=1.382,95%CI:1.057–1.808),high perceived difficulty in quitting(OR=1.297,95%CI:1.061–1.586),and moderate(OR=1.383,95%CI:1.174–1.629)or weak(OR=1.517,95%CI:1.251–1.841)willingness to quit.Factors negatively associated with relapse included having a college degree or higher(OR=0.796;95%CI:0.650–0.973),high confidence in quitting(OR=0.786;95%CI:0.629–0.983),and use of TCM(OR=0.276;95%CI:0.158–0.482).Enhancing self-efficacy in quitting appears crucial for preventing short-term relapse.The use of TCM may reduce relapse risk and warrants further investigation.
