The cavitated bifurcation problem in a solid sphere composed oftwo compressible hyper-elas- tic materials is examined. Thebifurcation solution for the composed sphere under a uniform radialtensile boundary dead-load i...The cavitated bifurcation problem in a solid sphere composed oftwo compressible hyper-elas- tic materials is examined. Thebifurcation solution for the composed sphere under a uniform radialtensile boundary dead-load is obtained. The bifurcation curves andthe stress contributions subsequent to the cavita- tion are given.The right and left bifurcation as well as the catastrophe andconcentration of stresses are ana- lyzed. The stability of solutionsis discussed through an energy comparison.展开更多
Because of the complexities of tire-road interaction,the wheels of a multi-wheel distributed electricdrive vehicle can easily slip under certain working conditions.As wheel slip affects the dynamic per-formance and st...Because of the complexities of tire-road interaction,the wheels of a multi-wheel distributed electricdrive vehicle can easily slip under certain working conditions.As wheel slip affects the dynamic per-formance and stability of the vehicle,it is crucial to control it and coordinate the driving force.With this aim,this paper presents a driving force coordination control strategy with road identification for eight-wheeled electric vehicles equipped with an in-wheel motor for each wheel.In the proposed control strategy,the road identification module estimates tire-road forces using an unscented Kalman filter al-gorithm and recognizes the road adhesion coefficient by employing the recursive least-square method According to road identification,the optimal sip ratio under the current driving condition is obtainedand a controller based on sliding mode control with a conditional integrator uses this value for accel-eration slip regulation.The anti-slip controller obtains the adjusting torque,which is integrated with the driver-command-based feedforward control torque to implement driving force coordination control.The results of hardware-in-loop simulation show that this control strategy can accurately estimate tire-roadrces as well as the friction coefficient,and thus,can effectively fulfill the purpose of driving force coordinated control under different driving conditions.展开更多
The spatial distributions and interannual variations of aerosol concentrations, aerosol optical depth （AOD）, aerosol direct radiative forcings, and their responses to heterogeneous reactions on dust surfaces over Ea...The spatial distributions and interannual variations of aerosol concentrations, aerosol optical depth （AOD）, aerosol direct radiative forcings, and their responses to heterogeneous reactions on dust surfaces over East Asia in March 2006-10 were investigated by utilizing a regional coupled climate-chemistry/aerosol model. Anthropogenic aerosol concentrations （inorganic ＋ carbonaceous） were higher in March 2006 and 2008, whereas soil dust reached its highest levels in March 2006 and 2010, resulting in stronger aerosol radiative forcings in these periods. The domain and five-year （2006-10） monthly mean concentrations of anthropogenic and dust aerosols, AOD, and radiative forcings at the surface （SURF） and at the top of the atmosphere （TOA） in March were 2.4 μg m 3 13.1 lag m^-3, 0.18, -19.0 W m^-2, and -7.4 W m^-2, respectively. Heterogeneous reactions led to an increase of total inorganic aerosol concentration; however, the ambient inorganic aerosol concentration decreased, resulting in a smaller AOD and weaker aerosol radiative forcings. In March 2006 and 2010, the changes in ambient inorganic aerosols, AOD, and aerosol radiative forcings were more evident. In terms of the domain and five-year averages, the total inorganic aerosol concentrations increased by 13.7% （0.17 μg m^-3） due to heterogeneous reactions, but the ambient inorganic aerosol concentrations were reduced by 10.5% （0.13 lag m-3）. As a result, the changes in AOD, SURF and TOA radiative forcings were estimated to be -3.9% （-0.007）, -1.7% （0.34 W m^-2）, and -4.3% （0.34 W m^-2）, respectively, in March over East Asia.展开更多
基金the National Natttral Science Foundation of China(No.19802012)
文摘The cavitated bifurcation problem in a solid sphere composed oftwo compressible hyper-elas- tic materials is examined. Thebifurcation solution for the composed sphere under a uniform radialtensile boundary dead-load is obtained. The bifurcation curves andthe stress contributions subsequent to the cavita- tion are given.The right and left bifurcation as well as the catastrophe andconcentration of stresses are ana- lyzed. The stability of solutionsis discussed through an energy comparison.
基金This work was supported by the Weapons and Equipment Pre-Research Project of China(No.301051102).
文摘Because of the complexities of tire-road interaction,the wheels of a multi-wheel distributed electricdrive vehicle can easily slip under certain working conditions.As wheel slip affects the dynamic per-formance and stability of the vehicle,it is crucial to control it and coordinate the driving force.With this aim,this paper presents a driving force coordination control strategy with road identification for eight-wheeled electric vehicles equipped with an in-wheel motor for each wheel.In the proposed control strategy,the road identification module estimates tire-road forces using an unscented Kalman filter al-gorithm and recognizes the road adhesion coefficient by employing the recursive least-square method According to road identification,the optimal sip ratio under the current driving condition is obtainedand a controller based on sliding mode control with a conditional integrator uses this value for accel-eration slip regulation.The anti-slip controller obtains the adjusting torque,which is integrated with the driver-command-based feedforward control torque to implement driving force coordination control.The results of hardware-in-loop simulation show that this control strategy can accurately estimate tire-roadrces as well as the friction coefficient,and thus,can effectively fulfill the purpose of driving force coordinated control under different driving conditions.
基金supported by the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No. KZCX2-YW-Q11-03)the National Basic Research Program of China(Grant No.2010CB950804)100 Talents Program of the Chinese Academy of Sciences
文摘The spatial distributions and interannual variations of aerosol concentrations, aerosol optical depth （AOD）, aerosol direct radiative forcings, and their responses to heterogeneous reactions on dust surfaces over East Asia in March 2006-10 were investigated by utilizing a regional coupled climate-chemistry/aerosol model. Anthropogenic aerosol concentrations （inorganic ＋ carbonaceous） were higher in March 2006 and 2008, whereas soil dust reached its highest levels in March 2006 and 2010, resulting in stronger aerosol radiative forcings in these periods. The domain and five-year （2006-10） monthly mean concentrations of anthropogenic and dust aerosols, AOD, and radiative forcings at the surface （SURF） and at the top of the atmosphere （TOA） in March were 2.4 μg m 3 13.1 lag m^-3, 0.18, -19.0 W m^-2, and -7.4 W m^-2, respectively. Heterogeneous reactions led to an increase of total inorganic aerosol concentration; however, the ambient inorganic aerosol concentration decreased, resulting in a smaller AOD and weaker aerosol radiative forcings. In March 2006 and 2010, the changes in ambient inorganic aerosols, AOD, and aerosol radiative forcings were more evident. In terms of the domain and five-year averages, the total inorganic aerosol concentrations increased by 13.7% （0.17 μg m^-3） due to heterogeneous reactions, but the ambient inorganic aerosol concentrations were reduced by 10.5% （0.13 lag m-3）. As a result, the changes in AOD, SURF and TOA radiative forcings were estimated to be -3.9% （-0.007）, -1.7% （0.34 W m^-2）, and -4.3% （0.34 W m^-2）, respectively, in March over East Asia.
