Overview of Preventive Conservation Research Work on Seismic Mitigation and Subway Vibration Control in Chengdu Museum of China

ABSTRACT

The 2008 Wenchuan earthquake brought numerous issues to the attention of researchers of seismic mitigation in Chinese museums. After the Wenchuan earthquake, the structural design team of Chengdu Museum conducted a series of research projects on seismic mitigation and subway vibration control design of buildings. These projects included the following topics: optimization of design, numerical simulation of seismic performance, analysis of key technologies for the base isolation structure, in-depth studies on structural vibrations caused by the nearby subway, and proposals for reducing structural vibrations. In 2015, after the superstructure of Chengdu Museum was completed, conservators evaluated the safety of permanent exhibitions under earthquake conditions. Seismic protection devices were installed on the showcases according to the preventive conservation requirements for museum collections. Reinforced measures were used for museum collections according to the methods suggested in the document ‘Specification for seismic protection of museum collection’ (WW/T 0069-2015). The conservators also built a systematic platform for earthquake monitoring for museum collections. Preventive conservation studies on seismic protection and subway vibration control in Chengdu Museum are summarized and forecasted.     

疑似王重民手札一封考证

王重民自1934年起赴欧美诸国访书多年,为海外汉学文献的研究作出了卓越贡献。文章针对学界认为是王重民在法国期间写给杨东讐的一封书信,使用文献分析法与考据法进行考证,从辨识信札客观文本出发,结合时代背景,参考文献史料,最后考辨出收信人是杨东蓴(莼),而不是杨东讐,信札真正的作者是北京大学历史系教授杨人楩。     

学科交叉人才培养途径的探索与实践——以机器人学科为例

随着科技的快速发展和新兴学科的不断涌现,未来科技的发展越来越需要复合型的创新人才。因此,培养学科交叉型人才已成为研究生教育的重要内容之一,本文分析了机器人学科的特点与优势,从研究生导师、学生、政策以及培养模式等几个方面着手,对研究生学科交叉型人才培养途径进行了详细的探讨,为高校学科交叉型人才培养提供参考与建议。     

浅谈云计算及其发展现状

云计算是基于多种技术的商业计算模型,将是21世纪的一种发展趋势,本文主要介绍了云计算的概念、特点、实现机制、提供的服务以及目前国内外的研究发展现状。     

传统项目学校的体育人文教育之研究——以温州市为例

通过对温州市体育传统项目学校体育人文教育的实证研究,探讨体育运动项目作为体育人文教育的载体所发挥的作用,论证体育人文教育在人文教育中的价值.研究表明,传统运动项目有其自身的文化背景,传统运动项目具有积淀与凝聚、体验与教养、约束与规范、导向与辐射等人文教育功能,其教育效果体现在知识本体和行为本体统一的人文学科教育与体质教育和精神教育统一的人文主义教育两个方面.     

Changes in running economy following downhill running

In this study, we examined the time course of changes in running economy following a 30-min downhill (-15%) run at 70% peak aerobic power (VO2peak). Ten young men performed level running at 65, 75, and 85% VO2peak (5 min for each intensity) before, immediately after, and 1 - 5 days after the downhill run, at which times oxygen consumption (VO2), minute ventilation, the respiratory exchange ratio (RER), heart rate, ratings of perceived exertion (RPE), and blood lactate concentration were measured. Stride length, stride frequency, and range of motion of the ankle, knee, and hip joints during the level runs were analysed using high-speed (120-Hz) video images. Downhill running induced reductions (7 - 21%, P < 0.05) in maximal isometric strength of the knee extensors, three- to six-fold increases in plasma creatine kinase activity and myoglobin concentration, and muscle soreness for 4 days after the downhill run. Oxygen consumption increased (4 - 7%, P < 0.05) immediately to 3 days after downhill running. There were also increases (P < 0.05) in heart rate, minute ventilation, RER, RPE, blood lactate concentration, and stride frequency, as well as reductions in stride length and range of motion of the ankle and knee. The results suggest that changes in running form and compromised muscle function due to muscle damage contribute to the reduction in running economy for 3 days after downhill running.     

湖北省体育系统所属体育场地现状分析

通过对湖北省体育系统所属体育场地设施现状的调查研究,进一步分析了体育系统所属的体育场地的建设、管理和运营现状,并在此基础上提出了一些建议,以期为相关决策部门提供参考依据。     

领域学习模型研究述评

学习理论是近年学校教育和教学关注的基本理论问题,它涉及到学生的学和教师的教.而领域学习模型是西方近20年来学科学习研究的最新成就,它主要是对不同学科专业学习心理的理论探讨.本文着重论述了该模型的主要内容及其特征并探讨了未来研究的方向,针对目前教学现状讨论了该模型对学科教学实践的启示,以期促进大学专业教学.     

Precision measurement of the Newtonian gravitational constant

The Newtonian gravitational constant G, which is one of the most important fundamental physical constants in nature, plays a significant role in the fields of theoretical physics, geophysics, astrophysics and astronomy. Although G was the first physical constant to be introduced in the history of science, it is considered to be one of the most difficult to measure accurately so far. Over the past two decades, eleven precision measurements of the gravitational constant have been performed, and the latest recommended value for G published by the Committee on Data for Science and Technology (CODATA) is (6.674 08 ± 0.000 31) × 10⁻¹¹ m³ kg⁻¹ s⁻² with a relative uncertainty of 47 parts per million. This uncertainty is the smallest compared with previous CODATA recommended values of G; however, it remains a relatively large uncertainty among other fundamental physical constants. In this paper we briefly review the history of the G measurement, and introduce eleven values of G adopted in CODATA 2014 after 2000 and our latest two values published in 2018 using two independent methods.     

导数是处理函数单调性问题的金钥匙

函数的单调性是高考的热点问题之一。在历年的高考试题中,考查或利用函数的单调性试题屡见不鲜,而且相应的问题都有一定的难度．新教材引进导数,为我们解决函数的单调性及相关问题带来了极大的方便．为了便于掌握,本文把这类问题分类解析,供参考．