Numerical modelling of the depth variation and the fluctuation of the thermocline under the effects of wind in the Bohai Sea

-In this paper, numerical modelling of the fluctuation of the thermocline in the Bohai Sea has been made using a two-dimensional nonlinear model in stratified ocean and the model for the depth of the thermocline under the effects of wind stirring. The computed results depict the variations of the fluctuation of the thermocline driven by different kinds of wind fields. The fluctuation of the thermocline in the Bohai Sea varies somewhat with different directions, paths and locations of typhoon (cyclone). Under the effects of strong wind, the thermoclines both sink due to mixing and fluctuate. Furthermore, the fluctuation of the thermocline speeds up mixing. At last, the thermoclines disappear after 12-15 h when the strong wind increases from Force 6 to Force 9.

Effect of phase fluctuation on Hopf bifurcation in a ladder type atomic system

Hopf bifurcation inducing lasing without inversion has been analyzed by taking into account the effect of phase fluctuation in the driving field based on a closed three level ladder-type atomic model. It is shown that due to the phase fluctuation of the driving field, the necessary threshold increases significantly. Furthermore the area domain to get lasing without inversion decreases as the driving field's linewidth increases.

A critical transition rule for broadening exponent of fluctuation and its effect on dissipation in chemical reaction-heat conduction coupling systems

A stochastic model of chemical reaction-heat conduction-diffusion for a one-dimensional gaseous system under Dirichlet or zero-fluxes boundary conditions is proposed in this paper. Based on this model,we extend the theory of the broadening exponent of critical fluctuations to cover the chemical reaction-heat conduction coupling systems as an asymptotic property of the corresponding Markovian master equation (ME),and establish a valid stochastic thermodynamics for such systems. As an illustration,the non-isothermal and inhomogeneous Schl-gl model is explicitly studied. Through an order analysis of the contributions from both the drift and diffusion to the evolution of the probability distribution in the corresponding Fokker-Planck equation(FPE) in the approach to bifurcation,we have identified the critical transition rule for the broadening exponent of the fluctuations due to the coupling between chemical reaction and heat conduction. It turns out that the dissipation induced by the critical fluctuations reaches a deterministic level,leading to a thermodynamic effect on the nonequilibrium physico-chemical processes.

THE EFFECTS OF CORRELATED SENSOR SIGNAL FLUCTUATION ON THE STATISTICAL PERFORMANCE OF AN AR HIGH RESOLUTION ARRAY PROCESSOR

The statistical performance of AR high resolution array processor in presence of correlated sensor signal fluctuation is studied. Mean square inverse beam pattern and pointing error are examined. Special attention is paid to the effects of reference sensor and correlation between sensors. It is shown that fluctuation causes broadening or even distortion of the mean square inverse beam pattern. Phase fluctuation causes pointing error. Its standard variance is proportional to that of fluctuation and is related to the number of sensors of the array. Correlation between sensors has important effects on pointing error.

On China’s Exchange Rate Flexibility and Stability: The More Flexible against the U.S. Dollar, the More Stable in Effective Terms

The Chinese authorities have often emphasized the importance of maintaining the renminbi＇s stable exchange rate without stating explicitly how this stability should be measured. This paper argues that the relevant concept for this stability should be in terms of the rnminbi＇s effective exchange rate, rather than its rate against any particular currency, such as the U. S. dollar. Under the current circumstances where key currencies＇ exchange rates fluctuate freely, if the authorities wish to maintain the stability of the renmnibi＇s effective exchange rate, they would want to let the renminbi＇s exchange rate fluctuate much more against the U. S. dollar than in the past because such fluctuations would greatly reduce the magnitude of the renminbi＇s fluctuations against other key currencies and thus its effective exchange rate. This point has been demonstrated by illustrative figures and by comparing the renminbi＇s hypothetical, greater exchange rate fluctuations with its actual fluctuations.

Is the spatial impact of digital financial inclusion on CO_(2) emissions real?A spatial fluctuation spillover perspective

Digital financial inclusion(DFI)has the advantage of promoting information sharing,reducing transaction costs,and providing microloan platforms for small and medium-sized enterprises.It has also made outstanding contributions to decreasing CO_(2) emissions.However,the volatility correlation between DFI and CO_(2) emissions is still relatively unexplored.This research uses the spatial autoregressive process with conditional heteroscedastic errors(SARspARCH)model to evaluate the spatial fluctuation spillover impacts of DFI on CO_(2) emissions in 284 Chinese cities covering the period 2011-2016 following the IPAT model.The results indicate that CO_(2) emissions have significant spatial spillover and volatility effects.The fitted value of SARspARCH estimation results is more realistic than the SAR and spARCH model.DFI alleviates average CO_(2) emissions in Chinese cities.Moreover,spatial volatility weakens the negative influence of DFI on average carbon emissions.This study provides insights from which governments can strengthen inter-regional communication and synergistic emission-reduction capabilities,and promote the digitization of the financial sector to achieve carbon neutrality goals.