Using a randomized experiment that we designed for the 2021 Chinese General Social Survey,this study conducts a conjoint analysis to explore the fertility potential among Chinese adults.We examine the separate impacts...Using a randomized experiment that we designed for the 2021 Chinese General Social Survey,this study conducts a conjoint analysis to explore the fertility potential among Chinese adults.We examine the separate impacts of different factors and their heterogeneity across social groups.The results suggest that fertility potential is context-dependent.In addition,greater economic resources and availability of childcare significantly increase fertility potential.However,preferences in terms of the care provider,family versus the market,vary by gender,educational level,and desired number of children.Notably,we also find that son preference no longer has a significant effect on fertility potential in China.In light of China’s current low fertility,our study suggests that childbearing behavior will become increasingly differentiated by socioeconomic status.Fertility-enhancing policies should focus on supplementing economic resources and improving access to childcare.展开更多
Stokes vectors direct detection(SV-DD)is an effective solution for short-reach optical communications.In this Letter,we investigate two-dimensional-modulation direct-detection systems based on three Stokes vector rece...Stokes vectors direct detection(SV-DD)is an effective solution for short-reach optical communications.In this Letter,we investigate two-dimensional-modulation direct-detection systems based on three Stokes vector receivers(SVRs).The influences of three key factors including the states-of-polarization(SOP),the splitting ratio of the coupler,and the excess loss(EL)are studied in detail.It is shown that the splitting ratio for achieving optimum performance will be changed with SOP and EL conditions.Among these SVRs,the3×3 coupler-based receiver with its optimal splitting ratio shows the best bit error rate performance and stability against the change of SOP.展开更多
文摘Using a randomized experiment that we designed for the 2021 Chinese General Social Survey,this study conducts a conjoint analysis to explore the fertility potential among Chinese adults.We examine the separate impacts of different factors and their heterogeneity across social groups.The results suggest that fertility potential is context-dependent.In addition,greater economic resources and availability of childcare significantly increase fertility potential.However,preferences in terms of the care provider,family versus the market,vary by gender,educational level,and desired number of children.Notably,we also find that son preference no longer has a significant effect on fertility potential in China.In light of China’s current low fertility,our study suggests that childbearing behavior will become increasingly differentiated by socioeconomic status.Fertility-enhancing policies should focus on supplementing economic resources and improving access to childcare.
基金supported by the National Natural Science Foundation of China(Nos.61671053,61871030,and 61435006)the Fundamental Research Funds for the Central Universities(No.FRF-BD-17-015A)+1 种基金the Foundation of Beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services,the State Key Laboratory of Advanced Optical Communication Systems Networks,China,the Hong Kong Polytechnic University(Nos.1-ZVGB,G-SB65,and 4-BCCK)the RGC of Hong Kong SAR Government(No.152248/15E)
文摘Stokes vectors direct detection(SV-DD)is an effective solution for short-reach optical communications.In this Letter,we investigate two-dimensional-modulation direct-detection systems based on three Stokes vector receivers(SVRs).The influences of three key factors including the states-of-polarization(SOP),the splitting ratio of the coupler,and the excess loss(EL)are studied in detail.It is shown that the splitting ratio for achieving optimum performance will be changed with SOP and EL conditions.Among these SVRs,the3×3 coupler-based receiver with its optimal splitting ratio shows the best bit error rate performance and stability against the change of SOP.