In time series modeling, the residuals are often checked for white noise and normality. In practice, the useful tests are Ljung Box test. Mcleod Li test and Lin Mudholkar test. In this paper, we present a nonparame...In time series modeling, the residuals are often checked for white noise and normality. In practice, the useful tests are Ljung Box test. Mcleod Li test and Lin Mudholkar test. In this paper, we present a nonparametric approach for checking the residuals of time series models. This approach is based on the maximal correlation coefficient ρ 2 * between the residuals and time t . The basic idea is to use the bootstrap to form the null distribution of the statistic ρ 2 * under the null hypothesis H 0:ρ 2 * =0. For calculating ρ 2 * , we proposes a ρ algorithm, analogous to ACE procedure. Power study shows this approach is more powerful than Ljung Box test. Meanwhile, some numerical results and two examples are reported in this paper.展开更多
We examine the time development of a wavepacket in a Non-Hermitian PT symmetric tight-bindingchain based on the Bethe ansatz solutions.The complete orthogonal sets in both unbroken and broken PT symmetryregions are es...We examine the time development of a wavepacket in a Non-Hermitian PT symmetric tight-bindingchain based on the Bethe ansatz solutions.The complete orthogonal sets in both unbroken and broken PT symmetryregions are established with respect to an inner product in terms of CPT conjugation.The dynamical development ofa stationary wavepacket is exhibited,showing the impacts from additional imaginary potentials within unbroken andbroken symmetric regimes.Our result indicates that there are distinct dynamic characteristics for both two regions.Theunbroken symmetric imaginary end potentials can be regarded as a special kind of boundary condition in the sense ofHermitian quantum mechanics.展开更多
In the proximity of an active fault, spatial variation of peak ground motion is significantly affected by the faulting mechanism. It has been observed that near fault ground motions consists of different characteristi...In the proximity of an active fault, spatial variation of peak ground motion is significantly affected by the faulting mechanism. It has been observed that near fault ground motions consists of different characteristics compared to the far fault ground motions. Near fault records, in the distance range of less than 100 m from the faults are not available except for few cases. Therefore numerical simulation of ground motions for such near-fault situations is necessary. In addition to the understanding of the phenomenon of near fault ground motion there is a need to enhance our understanding of the possible potential hazard that can be caused due to the future rupture activity by understanding the phenomenon of surface faulting. In this paper we propose numerical simulation based on discrete modeling to investigate the fault rupture propagation and its effect on the surface peak ground acceleration. In the present two dimensional study rupture propagation due to bedrock motion has been observed for different shear wave velocity. A model of size 1000× 150 m is selected for this purpose. It has been observed that as the stiffness of the media is decreasing, the affected surface is decreasing and also width of the shear crack zone is decreasing. Secondly, we attempted to study the ground motion on the surface due to the bedrock motion in presence of boulders in the soil media by keeping the boulder at different positions. We find that there is an increase in the shear zone as well as the PGA on the surface when the boulder is present on the foot wall and in the vicinity of the rupture zone. Finally, we performed the analysis using layered media and studied the affect of crack propagation and also the variation of peak accelerations. Findings from the study can be utilized to assess the damage potential of the near fault areas.展开更多
0106322不确定度的简化及应用[刊]/谢国亚//重庆邮电学院学报.—2000,12(4).—89~91(C) 在对总不确定度的 A 类分量及 B 类分量评定的合理简化的基础上,确定了总不确定度的表示模式,并介绍了它们的应用。参30106323GSM 移动网络室内信...0106322不确定度的简化及应用[刊]/谢国亚//重庆邮电学院学报.—2000,12(4).—89~91(C) 在对总不确定度的 A 类分量及 B 类分量评定的合理简化的基础上,确定了总不确定度的表示模式,并介绍了它们的应用。参30106323GSM 移动网络室内信号的测试方法浅谈[刊]/李戈//移动通信.—2000,24(6).—58~59(C)展开更多
文摘In time series modeling, the residuals are often checked for white noise and normality. In practice, the useful tests are Ljung Box test. Mcleod Li test and Lin Mudholkar test. In this paper, we present a nonparametric approach for checking the residuals of time series models. This approach is based on the maximal correlation coefficient ρ 2 * between the residuals and time t . The basic idea is to use the bootstrap to form the null distribution of the statistic ρ 2 * under the null hypothesis H 0:ρ 2 * =0. For calculating ρ 2 * , we proposes a ρ algorithm, analogous to ACE procedure. Power study shows this approach is more powerful than Ljung Box test. Meanwhile, some numerical results and two examples are reported in this paper.
基金Support by the CNSF Grants Nos.10874091 and 2006CB921205
文摘We examine the time development of a wavepacket in a Non-Hermitian PT symmetric tight-bindingchain based on the Bethe ansatz solutions.The complete orthogonal sets in both unbroken and broken PT symmetryregions are established with respect to an inner product in terms of CPT conjugation.The dynamical development ofa stationary wavepacket is exhibited,showing the impacts from additional imaginary potentials within unbroken andbroken symmetric regimes.Our result indicates that there are distinct dynamic characteristics for both two regions.Theunbroken symmetric imaginary end potentials can be regarded as a special kind of boundary condition in the sense ofHermitian quantum mechanics.
文摘In the proximity of an active fault, spatial variation of peak ground motion is significantly affected by the faulting mechanism. It has been observed that near fault ground motions consists of different characteristics compared to the far fault ground motions. Near fault records, in the distance range of less than 100 m from the faults are not available except for few cases. Therefore numerical simulation of ground motions for such near-fault situations is necessary. In addition to the understanding of the phenomenon of near fault ground motion there is a need to enhance our understanding of the possible potential hazard that can be caused due to the future rupture activity by understanding the phenomenon of surface faulting. In this paper we propose numerical simulation based on discrete modeling to investigate the fault rupture propagation and its effect on the surface peak ground acceleration. In the present two dimensional study rupture propagation due to bedrock motion has been observed for different shear wave velocity. A model of size 1000× 150 m is selected for this purpose. It has been observed that as the stiffness of the media is decreasing, the affected surface is decreasing and also width of the shear crack zone is decreasing. Secondly, we attempted to study the ground motion on the surface due to the bedrock motion in presence of boulders in the soil media by keeping the boulder at different positions. We find that there is an increase in the shear zone as well as the PGA on the surface when the boulder is present on the foot wall and in the vicinity of the rupture zone. Finally, we performed the analysis using layered media and studied the affect of crack propagation and also the variation of peak accelerations. Findings from the study can be utilized to assess the damage potential of the near fault areas.
文摘0106322不确定度的简化及应用[刊]/谢国亚//重庆邮电学院学报.—2000,12(4).—89~91(C) 在对总不确定度的 A 类分量及 B 类分量评定的合理简化的基础上,确定了总不确定度的表示模式,并介绍了它们的应用。参30106323GSM 移动网络室内信号的测试方法浅谈[刊]/李戈//移动通信.—2000,24(6).—58~59(C)