This paper proposes a novel method for estimating the sparse inverse covariance matrixfor longitudinal data with informative dropouts. Based on the modified Cholesky decomposition,the sparse inverse covariance matrix ...This paper proposes a novel method for estimating the sparse inverse covariance matrixfor longitudinal data with informative dropouts. Based on the modified Cholesky decomposition,the sparse inverse covariance matrix is modelled by the autoregressive regression model,which guarantees the positive definiteness of the covariance matrix. To account for the informativedropouts, we then propose a penalized estimating equation method using the inverse probabilityweighting approach. The informative dropout propensity parameters are estimated by the generalizedmethod of moments. The asymptotic properties are investigated for the resulting estimators.Finally, we illustrate the effectiveness and feasibility of the proposed method through Monte Carlosimulations and a practical application.展开更多
在微光像增强型电荷耦合器件(Intensified Charge-coupled Device,ICCD)积分时间内,空间振动影响微光ICCD相机的成像,导致成像质量下降。对于振动环境下微光ICCD相机成像,采用动态调制传递函数(modulation transfer function,MTF)评价...在微光像增强型电荷耦合器件(Intensified Charge-coupled Device,ICCD)积分时间内,空间振动影响微光ICCD相机的成像,导致成像质量下降。对于振动环境下微光ICCD相机成像,采用动态调制传递函数(modulation transfer function,MTF)评价空间振动对成像质量影响。结合微光ICCD相机特有结构,提出微光ICCD相机的动态MTF理论模型,分析低频正弦振动及高频正弦振动中,振动幅度、振动周期、积分时间等不同因素对成像质量的影响。展开更多
In this paper,we show by Hilbert Uniqueness Method that the boundary value problem of fifth-order KdV equation{y_(t)-y_(5x)=0,(x,t)∈(0,2π)×(0,T),y(t,2π)-y(t,0)=h_(0)(t),y_(x)(t,2π)-y_(x)(t,0)=h_(1)(t),y_(2x)(...In this paper,we show by Hilbert Uniqueness Method that the boundary value problem of fifth-order KdV equation{y_(t)-y_(5x)=0,(x,t)∈(0,2π)×(0,T),y(t,2π)-y(t,0)=h_(0)(t),y_(x)(t,2π)-y_(x)(t,0)=h_(1)(t),y_(2x)(t,2π)-y_(2x)(t,0)=h_(2)(t),y_(3x)(t,2π)-y_(3x)(t,0)=h_(3)(t),y_(4x)(t,2π)-y_(4x)(t,0)=h_(4)(t),(with boundary data as control inputs)is exact controllability.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.12171450).
文摘This paper proposes a novel method for estimating the sparse inverse covariance matrixfor longitudinal data with informative dropouts. Based on the modified Cholesky decomposition,the sparse inverse covariance matrix is modelled by the autoregressive regression model,which guarantees the positive definiteness of the covariance matrix. To account for the informativedropouts, we then propose a penalized estimating equation method using the inverse probabilityweighting approach. The informative dropout propensity parameters are estimated by the generalizedmethod of moments. The asymptotic properties are investigated for the resulting estimators.Finally, we illustrate the effectiveness and feasibility of the proposed method through Monte Carlosimulations and a practical application.
文摘在微光像增强型电荷耦合器件(Intensified Charge-coupled Device,ICCD)积分时间内,空间振动影响微光ICCD相机的成像,导致成像质量下降。对于振动环境下微光ICCD相机成像,采用动态调制传递函数(modulation transfer function,MTF)评价空间振动对成像质量影响。结合微光ICCD相机特有结构,提出微光ICCD相机的动态MTF理论模型,分析低频正弦振动及高频正弦振动中,振动幅度、振动周期、积分时间等不同因素对成像质量的影响。
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LY18A010024)National Natural Science Foundation of China(No.12075208).
文摘In this paper,we show by Hilbert Uniqueness Method that the boundary value problem of fifth-order KdV equation{y_(t)-y_(5x)=0,(x,t)∈(0,2π)×(0,T),y(t,2π)-y(t,0)=h_(0)(t),y_(x)(t,2π)-y_(x)(t,0)=h_(1)(t),y_(2x)(t,2π)-y_(2x)(t,0)=h_(2)(t),y_(3x)(t,2π)-y_(3x)(t,0)=h_(3)(t),y_(4x)(t,2π)-y_(4x)(t,0)=h_(4)(t),(with boundary data as control inputs)is exact controllability.
