This article investigates the macroeconomic consequences of foreign asset-freezing sanctions,a tool utilized by several Western nations amid recent geopolitical tensions.Specifically,it examines the repercussions of s...This article investigates the macroeconomic consequences of foreign asset-freezing sanctions,a tool utilized by several Western nations amid recent geopolitical tensions.Specifically,it examines the repercussions of such sanctions on open economies,finding that they may experience a sharp recession and currency crisis.To quantify the impact,we develop a new Keynesian dynamic stochastic general equilibrium model with financial frictions and an asset-freezing channel for an open economy.We also calibrate our model to capture the unique structures of the Russian economy.The quantitative analysis of the model demonstrates that an abrupt asset-freezing sanction would lead to large output losses and high inflation increases.Our counterfactual examination reveals that higher elasticity of import substitution and lower elasticity of export substitution could alleviate the impact of foreign sanctions,whereas more aggressive monetary policy may have positive but limited stabilization effects.Notably,the monetary authority must navigate a trade-off between stabilizing output and managing inflation resulting from the cash-in-advance channel.展开更多
A macroscopically nominal flat surface is rough at the nanoscale level and consists of nanoasperities.Therefore,the frictional properties of the macroscale-level rough surface are determined by the mechanical behavior...A macroscopically nominal flat surface is rough at the nanoscale level and consists of nanoasperities.Therefore,the frictional properties of the macroscale-level rough surface are determined by the mechanical behaviors of nanoasperity contact pairs under shear.In this work,we first used molecular dynamics simulations to study the non-adhesive shear between single contact pairs.Subsequently,to estimate the friction coefficient of rough surfaces,we implemented the frictional behavior of a single contact pair into a Greenwood-Williamson-type statistical model.By employing the present multiscale approach,we used the size,rate,and orientation effects,which originated from nanoscale dislocation plasticity,to determine the dependence of the macroscale friction coefficient on system parameters,such as the surface roughness,separation,loading velocity,and direction.Our model predicts an unconventional dependence of the friction coefficient on the normal contact load,which has been observed in nanoscale frictional tests.Therefore,this model represents one step toward understanding some of the relevant macroscopic phenomena of surface friction at the nanoscale level.展开更多
基金the National Natural Science Foundation of China(Nos.72150003 and 72125007).
文摘This article investigates the macroeconomic consequences of foreign asset-freezing sanctions,a tool utilized by several Western nations amid recent geopolitical tensions.Specifically,it examines the repercussions of such sanctions on open economies,finding that they may experience a sharp recession and currency crisis.To quantify the impact,we develop a new Keynesian dynamic stochastic general equilibrium model with financial frictions and an asset-freezing channel for an open economy.We also calibrate our model to capture the unique structures of the Russian economy.The quantitative analysis of the model demonstrates that an abrupt asset-freezing sanction would lead to large output losses and high inflation increases.Our counterfactual examination reveals that higher elasticity of import substitution and lower elasticity of export substitution could alleviate the impact of foreign sanctions,whereas more aggressive monetary policy may have positive but limited stabilization effects.Notably,the monetary authority must navigate a trade-off between stabilizing output and managing inflation resulting from the cash-in-advance channel.
文摘A macroscopically nominal flat surface is rough at the nanoscale level and consists of nanoasperities.Therefore,the frictional properties of the macroscale-level rough surface are determined by the mechanical behaviors of nanoasperity contact pairs under shear.In this work,we first used molecular dynamics simulations to study the non-adhesive shear between single contact pairs.Subsequently,to estimate the friction coefficient of rough surfaces,we implemented the frictional behavior of a single contact pair into a Greenwood-Williamson-type statistical model.By employing the present multiscale approach,we used the size,rate,and orientation effects,which originated from nanoscale dislocation plasticity,to determine the dependence of the macroscale friction coefficient on system parameters,such as the surface roughness,separation,loading velocity,and direction.Our model predicts an unconventional dependence of the friction coefficient on the normal contact load,which has been observed in nanoscale frictional tests.Therefore,this model represents one step toward understanding some of the relevant macroscopic phenomena of surface friction at the nanoscale level.
