Population ageing and high financial leverage are two common problems .faced by the worM＇s major economies. The recent financial crisis proved that the two issues could lead to systemic risk if not handled properly. ...Population ageing and high financial leverage are two common problems .faced by the worM＇s major economies. The recent financial crisis proved that the two issues could lead to systemic risk if not handled properly. Based on dynamic panel data from 1980 to 2012 in 119 countries, this paper examines the impact of population ageing on financial leverage J？om an empirical point of view and finds that there is a signOqcant inverted U-shape relationship between the two. In addition, empirical studies show that after passing the ＂turning point＂ of ageing, there will be a marked increase in the probability of financial crisis during the ＂deleveraging＂ process. It can be projected from the empirical conclusions of this paper that China will likely enter the range of a turning point between 2019 and 2028. After that, population ageing, deleveraging and asset price collapse may have a ＂resonance＂ effect to severely impact the stability of the financial system. Therefore, China should shift to more proactive macro financial regulations as quickly as possible, as dynamic and robust management of financial leverage and forward-looking control of bubbles could ensure that the financial system remain flexible enough to avoid systemic risk to the greatest extent.展开更多
To improve the efficiency and amplify the exciting force of a shake table,a novel variable stiffness mechanism(VSM)constructed by four leaf spring-lever combinations(LSLCs)was designed.Three VSMs were installed in par...To improve the efficiency and amplify the exciting force of a shake table,a novel variable stiffness mechanism(VSM)constructed by four leaf spring-lever combinations(LSLCs)was designed.Three VSMs were installed in parallel on the traditional hydraulic shake table to constitute a resonant shake table(RST).The static model of the VSM and the dynamic model of the RST were constructed by considering the large deflection of leaf springs and the geometrical nonlinearity of L-shaped levers.The variable stiffness property of LSLCs was analyzed and verified through static experiments.The simulation and vibration experiments on the dynamic properties of the RST prototype were conducted.The results show that compared with traditional shake tables,the RST consumes lower exciting force in a specified frequency bandwidth when outputting the same displacement of vibration.Under a harmonic vibrational excitation,the RST is effective for vibration enhancement using broadband frequency resonance and can save energy to some extent.The broadband resonance technology exhibits considerable potential in practical engineering applications.展开更多
基金sponsored by the National Social Science Foundation of China(Grant No.12&ZD089)the National Natural Science Foundation of China(Grant No.71403277)
文摘Population ageing and high financial leverage are two common problems .faced by the worM＇s major economies. The recent financial crisis proved that the two issues could lead to systemic risk if not handled properly. Based on dynamic panel data from 1980 to 2012 in 119 countries, this paper examines the impact of population ageing on financial leverage J？om an empirical point of view and finds that there is a signOqcant inverted U-shape relationship between the two. In addition, empirical studies show that after passing the ＂turning point＂ of ageing, there will be a marked increase in the probability of financial crisis during the ＂deleveraging＂ process. It can be projected from the empirical conclusions of this paper that China will likely enter the range of a turning point between 2019 and 2028. After that, population ageing, deleveraging and asset price collapse may have a ＂resonance＂ effect to severely impact the stability of the financial system. Therefore, China should shift to more proactive macro financial regulations as quickly as possible, as dynamic and robust management of financial leverage and forward-looking control of bubbles could ensure that the financial system remain flexible enough to avoid systemic risk to the greatest extent.
基金The National Natural Science Foundation of China(No.41876218,51905210)。
文摘To improve the efficiency and amplify the exciting force of a shake table,a novel variable stiffness mechanism(VSM)constructed by four leaf spring-lever combinations(LSLCs)was designed.Three VSMs were installed in parallel on the traditional hydraulic shake table to constitute a resonant shake table(RST).The static model of the VSM and the dynamic model of the RST were constructed by considering the large deflection of leaf springs and the geometrical nonlinearity of L-shaped levers.The variable stiffness property of LSLCs was analyzed and verified through static experiments.The simulation and vibration experiments on the dynamic properties of the RST prototype were conducted.The results show that compared with traditional shake tables,the RST consumes lower exciting force in a specified frequency bandwidth when outputting the same displacement of vibration.Under a harmonic vibrational excitation,the RST is effective for vibration enhancement using broadband frequency resonance and can save energy to some extent.The broadband resonance technology exhibits considerable potential in practical engineering applications.
