The prediction for the smoothed monthly mean sunspot numbers (hereafter SMSNs) of solar cycle 23, which was given with a similar cycle method proposed by us at the beginning time of cycle 23, is analyzed and verified ...The prediction for the smoothed monthly mean sunspot numbers (hereafter SMSNs) of solar cycle 23, which was given with a similar cycle method proposed by us at the beginning time of cycle 23, is analyzed and verified in this paper. Using our predicted maximum SMSN and the ascending length for solar cycle 24, and as- suming their relative errors to be respectively 20% and ± 7 months, solar cycles 2, 4, 8, 11, 17, 20 and 23 are selected to be the similar cycles to cycle 24. The selected solar cycles are divided into two groups. The first group consists of all the selected cycles; while the second group consists of only cycles 11, 17, 20 and 23. Two SMSN time profiles then may be obtained, respectively, for the two similar cycle groups. No significant difference is found between the two predicted time profiles. Consid- ering the latest observed sunspot number so far available for cycle 23 and the pre- dictions for the minimum SMSN of cycle 24, a date calibration is done for the ob- tained time profiles, and thus, SMSNs for 127 months of cycle 24, from October 2007 to April 2018, are predicted.展开更多
As a new energy storage element,supercapacitors have characteristics such as high power density,fast charge and discharge rates,green environmental protection,and long cycle life.Temperature is an important parameter ...As a new energy storage element,supercapacitors have characteristics such as high power density,fast charge and discharge rates,green environmental protection,and long cycle life.Temperature is an important parameter of supercapacitors which significantly influences the stability of the supercapacitors.In this study,the finite element method is used to realize a coupling between a one-dimensional electrochemical model and a three-dimensional thermal model.Then,based on this model,the concept of limited cycle numbers is defined,and different unit quantities,unit size,and the effect of temperature under different temperature environments such as low temperature,room temperature,and high temperature on stacked-type supercapacitors is studied.Finally,stacked-type supercapacitors are compared with rolled-type supercapacitors considering the same cell size,density,and volume approximations.The simulation results show that the higher the number of packaging units,the lower is the limit cycle number.This phenomenon is more pronounced under high current than under low current conditions.Increasing the package size of the porous electrode or separator decreases the limiting cycles.Under the same unit volume scenario,improving the separator size proportion can accurately control the temperature rise at small current values.Under the same material,volume,and density approximations,the temperature rises slowly for stacked-type supercapacitors as compared to rolled-type supercapacitors.This phenomenon is more pronounced with an increase in current.展开更多
The X ray (1-8?) flux data of the solar flares are analyzed. The data used were obtained on GOES satellite during the solar cycles 21 and 22. The total number of the flares is more than 33000. The flare distributions ...The X ray (1-8?) flux data of the solar flares are analyzed. The data used were obtained on GOES satellite during the solar cycles 21 and 22. The total number of the flares is more than 33000. The flare distributions according to their X ray classes, durations and intensities are constructed. The evolution of these distributions in solar cycle as well as from cycle to cycle is studied. The statistical analysis of the flare characteristics is made. There was confirmed the result of more frequent occurrence for powerful flares in cycle 21 decline phase.展开更多
基金the National Natural Science Foundation of China (Grant Nos. 10673017 and 10733020) the National Basic Research Program of China (Grant No. 2006CB806307)
文摘The prediction for the smoothed monthly mean sunspot numbers (hereafter SMSNs) of solar cycle 23, which was given with a similar cycle method proposed by us at the beginning time of cycle 23, is analyzed and verified in this paper. Using our predicted maximum SMSN and the ascending length for solar cycle 24, and as- suming their relative errors to be respectively 20% and ± 7 months, solar cycles 2, 4, 8, 11, 17, 20 and 23 are selected to be the similar cycles to cycle 24. The selected solar cycles are divided into two groups. The first group consists of all the selected cycles; while the second group consists of only cycles 11, 17, 20 and 23. Two SMSN time profiles then may be obtained, respectively, for the two similar cycle groups. No significant difference is found between the two predicted time profiles. Consid- ering the latest observed sunspot number so far available for cycle 23 and the pre- dictions for the minimum SMSN of cycle 24, a date calibration is done for the ob- tained time profiles, and thus, SMSNs for 127 months of cycle 24, from October 2007 to April 2018, are predicted.
文摘As a new energy storage element,supercapacitors have characteristics such as high power density,fast charge and discharge rates,green environmental protection,and long cycle life.Temperature is an important parameter of supercapacitors which significantly influences the stability of the supercapacitors.In this study,the finite element method is used to realize a coupling between a one-dimensional electrochemical model and a three-dimensional thermal model.Then,based on this model,the concept of limited cycle numbers is defined,and different unit quantities,unit size,and the effect of temperature under different temperature environments such as low temperature,room temperature,and high temperature on stacked-type supercapacitors is studied.Finally,stacked-type supercapacitors are compared with rolled-type supercapacitors considering the same cell size,density,and volume approximations.The simulation results show that the higher the number of packaging units,the lower is the limit cycle number.This phenomenon is more pronounced under high current than under low current conditions.Increasing the package size of the porous electrode or separator decreases the limiting cycles.Under the same unit volume scenario,improving the separator size proportion can accurately control the temperature rise at small current values.Under the same material,volume,and density approximations,the temperature rises slowly for stacked-type supercapacitors as compared to rolled-type supercapacitors.This phenomenon is more pronounced with an increase in current.
文摘The X ray (1-8?) flux data of the solar flares are analyzed. The data used were obtained on GOES satellite during the solar cycles 21 and 22. The total number of the flares is more than 33000. The flare distributions according to their X ray classes, durations and intensities are constructed. The evolution of these distributions in solar cycle as well as from cycle to cycle is studied. The statistical analysis of the flare characteristics is made. There was confirmed the result of more frequent occurrence for powerful flares in cycle 21 decline phase.