Assessment of time dependent seismic hazards on segments of active fault is one of the important techniques of long term earthquake forecast for specific locations. It is based on the data from quantitatively seismo g...Assessment of time dependent seismic hazards on segments of active fault is one of the important techniques of long term earthquake forecast for specific locations. It is based on the data from quantitatively seismo geologic investigation in active faults and expresses seismic hazards of a fault segment with both the earthquake occurrence probability, which increases as the elapsed time increases, and the magnitude predicted. Through summing up and analyzing main technical steps in research of the recent decade, some defects in the current theory and model of this technique are pointed out. For instance, the probabilistic models for recurrence interval are based solely on the quasi periodic behavior of earthquake recurrence, ignoring behavior’s diversity that possibly exists. Variability of repeated rupture dimensions in various cycles is considered inadequately in fault segmentation research, etc. It is most important for improving the reliability of the result of seismic hazard assessment to reveal actual earthquake recurrence behavior and its generalities, and to update relevant models for evaluating probabilistic earthquake hazard based on the behavior and generalities.展开更多
Abstract This summary report highlights the confluence of continued downward pressures and deflation scares in the face of looming uncertainty in China＇s key macroeconomic landscapes. Counterfactual analyses and poli...Abstract This summary report highlights the confluence of continued downward pressures and deflation scares in the face of looming uncertainty in China＇s key macroeconomic landscapes. Counterfactual analyses and policy simulations are conducted, in addition to benchmark forecasts, based on IAR-CMM model and taking into account both cyclical and secular factors. Economic deceleration is projected to continue in the short to medium term, with real GDP growth declining to 6.3% （5.5% using more reliable instead of official data） in 2016 and facing a significant risk of sliding further down in 2017. Five key factors contributing to the weak outlook, additional to frictions and impediments associated with economic transition/restructuring and lackluster domestic/external demands, are identified, including： lack of new growth/ development engine, exhaustion of government-led driving force, the crowding-out of private sectors by state-owned enterprises （SOEs） with excess capacity／capital overhang, nonperforming government sectors and officials, and twist or misinterpretation of the ＂New Normal.＂ A root cause of these problems, lying with sluggishness in China＇s transformation into a market based economy, has to do with overpowered government but underpowered market in resource allocation and government underperformance in enforcing integrity and transparency in the marketplace and in providing public goods and services. At the nexus between inclusive growth and institutional transformation are market oriented and rule of law governed structural reforms and harmonious development. As such, fundamental institutional reforms that dialectically balance demand and supply side factors and properly weigh short run stabilization against long run development should be elevated to the top of the agenda.展开更多
文摘Assessment of time dependent seismic hazards on segments of active fault is one of the important techniques of long term earthquake forecast for specific locations. It is based on the data from quantitatively seismo geologic investigation in active faults and expresses seismic hazards of a fault segment with both the earthquake occurrence probability, which increases as the elapsed time increases, and the magnitude predicted. Through summing up and analyzing main technical steps in research of the recent decade, some defects in the current theory and model of this technique are pointed out. For instance, the probabilistic models for recurrence interval are based solely on the quasi periodic behavior of earthquake recurrence, ignoring behavior’s diversity that possibly exists. Variability of repeated rupture dimensions in various cycles is considered inadequately in fault segmentation research, etc. It is most important for improving the reliability of the result of seismic hazard assessment to reveal actual earthquake recurrence behavior and its generalities, and to update relevant models for evaluating probabilistic earthquake hazard based on the behavior and generalities.
文摘Abstract This summary report highlights the confluence of continued downward pressures and deflation scares in the face of looming uncertainty in China＇s key macroeconomic landscapes. Counterfactual analyses and policy simulations are conducted, in addition to benchmark forecasts, based on IAR-CMM model and taking into account both cyclical and secular factors. Economic deceleration is projected to continue in the short to medium term, with real GDP growth declining to 6.3% （5.5% using more reliable instead of official data） in 2016 and facing a significant risk of sliding further down in 2017. Five key factors contributing to the weak outlook, additional to frictions and impediments associated with economic transition/restructuring and lackluster domestic/external demands, are identified, including： lack of new growth/ development engine, exhaustion of government-led driving force, the crowding-out of private sectors by state-owned enterprises （SOEs） with excess capacity／capital overhang, nonperforming government sectors and officials, and twist or misinterpretation of the ＂New Normal.＂ A root cause of these problems, lying with sluggishness in China＇s transformation into a market based economy, has to do with overpowered government but underpowered market in resource allocation and government underperformance in enforcing integrity and transparency in the marketplace and in providing public goods and services. At the nexus between inclusive growth and institutional transformation are market oriented and rule of law governed structural reforms and harmonious development. As such, fundamental institutional reforms that dialectically balance demand and supply side factors and properly weigh short run stabilization against long run development should be elevated to the top of the agenda.
文摘极移参数(polar motion,PM)是地球定向参数(earth orientation parameter,EOP)的重要组成部分,在天文大地测量、卫星的导航定位以及卫星的自主定轨等领域有重要的应用。本文首先利用国际地球自转服务(international earth rotation and reference systems service,IERS)提供的极移观测值进行极移时间序列频谱分析及周期项的提取。结果表明,快速傅里叶变换与离散傅里叶变换周期项提取到的周期项基本无差异,但极移X、Y分量时变分析结果存在差异。此外,本文将正弦逼近应用到极移参数的预报,对于长时间尺度的极移参数预报最小二乘外推模型效果最佳,但预报模型精度易受到周期项提取结果的影响;最小二乘外推模型在极移正向预报和反推拟合效果相近,借助正弦逼近方法可以一定程度上增强模型拟合效果。上述研究结果可为地球自转参数的预报研究提供参考。
