With the full-vector plane-wave method （FVPWM） and the full-vector beam propagation method （FVBPM）, the dependences of the band-gap and mode characteristics on material index and cladding structure parameter in an...With the full-vector plane-wave method （FVPWM） and the full-vector beam propagation method （FVBPM）, the dependences of the band-gap and mode characteristics on material index and cladding structure parameter in anti- resonance guiding photonic crystal fibres （ARGPCFs） are sufficiently analysed. An ARGPCF operating in the near- infrared wavelength is shown. The influences of the high index cylinders, glass interstitial apexes and silica structure on the characteristics of band-gaps and modes are deeply investigated. The equivalent planar waveguide theory is used for analysing such an ARGPCF filled by the isotropic materials, and the resonance and the anti-resonance characteristics r：~n h~ w~｜] r^r~dlrtpd展开更多
The classical Pauli particle(CPP) serves as a slow manifold, substituting the conventional guiding center dynamics. Based on the CPP, we utilize the averaged vector field(AVF) method in the computations of drift orbit...The classical Pauli particle(CPP) serves as a slow manifold, substituting the conventional guiding center dynamics. Based on the CPP, we utilize the averaged vector field(AVF) method in the computations of drift orbits. Demonstrating significantly higher efficiency, this advanced method is capable of accomplishing the simulation in less than one-third of the time of directly computing the guiding center motion. In contrast to the CPP-based Boris algorithm, this approach inherits the advantages of the AVF method, yielding stable trajectories even achieved with a tenfold time step and reducing the energy error by two orders of magnitude. By comparing these two CPP algorithms with the traditional RK4 method, the numerical results indicate a remarkable performance in terms of both the computational efficiency and error elimination. Moreover, we verify the properties of slow manifold integrators and successfully observe the bounce on both sides of the limiting slow manifold with deliberately chosen perturbed initial conditions. To evaluate the practical value of the methods, we conduct simulations in non-axisymmetric perturbation magnetic fields as part of the experiments,demonstrating that our CPP-based AVF method can handle simulations under complex magnetic field configurations with high accuracy, which the CPP-based Boris algorithm lacks. Through numerical experiments, we demonstrate that the CPP can replace guiding center dynamics in using energy-preserving algorithms for computations, providing a new, efficient, as well as stable approach for applying structure-preserving algorithms in plasma simulations.展开更多
为了提高多目标异常行为的识别精度,提出红外图像序列中多运动目标异常行为识别方法。对红外图像展开一次引导滤波,得到其信息细节,对上述图像再次展开引导滤波,得到二次引导滤波后信息细节,同时和一次引导滤波后信息细节作差,并把上述...为了提高多目标异常行为的识别精度,提出红外图像序列中多运动目标异常行为识别方法。对红外图像展开一次引导滤波,得到其信息细节,对上述图像再次展开引导滤波,得到二次引导滤波后信息细节,同时和一次引导滤波后信息细节作差,并把上述获取的图像细节信息与输入图像展开加权求和,得到增强后的红外图像。将人体骨骼关节点作为依据,分别获取关节速度、运动员重心以及关节角度特征,构建双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,Bi-LSTM),并将上述特征输入该模型内,实现多运动目标异常行为识别。经实验验证得出,所提方法对红外图像的增强效果好,多目标异常行为的识别精度高。展开更多
基金partly supported by the National Key Basic Research Special Foundation of China (Grant Nos. 2010CB327605 and 2010CB328300)the National High-Technology Research and Development Program of China (Grant No. 2009AA01Z220)+3 种基金the Key Grant of the Chinese Ministry of Education (Grant No. 109015)the Discipline Co-construction Project of Beijing Municipal Commission of Education,China (Grant No. YB20081001301)the Open Fund of Key Laboratory of Information Photonics and Optical Communications (Beijing University of Posts and Telecommunications),Chinese Ministry of Educationthe Specialized Research Fund for the Doctoral Program of Beijing University of Posts and Telecommunications (Grant No. CX201023)
文摘With the full-vector plane-wave method （FVPWM） and the full-vector beam propagation method （FVBPM）, the dependences of the band-gap and mode characteristics on material index and cladding structure parameter in anti- resonance guiding photonic crystal fibres （ARGPCFs） are sufficiently analysed. An ARGPCF operating in the near- infrared wavelength is shown. The influences of the high index cylinders, glass interstitial apexes and silica structure on the characteristics of band-gaps and modes are deeply investigated. The equivalent planar waveguide theory is used for analysing such an ARGPCF filled by the isotropic materials, and the resonance and the anti-resonance characteristics r：~n h~ w~｜] r^r~dlrtpd
基金supported by National Natural Science Foundation of China (Nos. 11975068 and 11925501)the National Key R&D Program of China (No. 2022YFE03090000)the Fundamental Research Funds for the Central Universities (No. DUT22ZD215)。
文摘The classical Pauli particle(CPP) serves as a slow manifold, substituting the conventional guiding center dynamics. Based on the CPP, we utilize the averaged vector field(AVF) method in the computations of drift orbits. Demonstrating significantly higher efficiency, this advanced method is capable of accomplishing the simulation in less than one-third of the time of directly computing the guiding center motion. In contrast to the CPP-based Boris algorithm, this approach inherits the advantages of the AVF method, yielding stable trajectories even achieved with a tenfold time step and reducing the energy error by two orders of magnitude. By comparing these two CPP algorithms with the traditional RK4 method, the numerical results indicate a remarkable performance in terms of both the computational efficiency and error elimination. Moreover, we verify the properties of slow manifold integrators and successfully observe the bounce on both sides of the limiting slow manifold with deliberately chosen perturbed initial conditions. To evaluate the practical value of the methods, we conduct simulations in non-axisymmetric perturbation magnetic fields as part of the experiments,demonstrating that our CPP-based AVF method can handle simulations under complex magnetic field configurations with high accuracy, which the CPP-based Boris algorithm lacks. Through numerical experiments, we demonstrate that the CPP can replace guiding center dynamics in using energy-preserving algorithms for computations, providing a new, efficient, as well as stable approach for applying structure-preserving algorithms in plasma simulations.
文摘为了提高多目标异常行为的识别精度,提出红外图像序列中多运动目标异常行为识别方法。对红外图像展开一次引导滤波,得到其信息细节,对上述图像再次展开引导滤波,得到二次引导滤波后信息细节,同时和一次引导滤波后信息细节作差,并把上述获取的图像细节信息与输入图像展开加权求和,得到增强后的红外图像。将人体骨骼关节点作为依据,分别获取关节速度、运动员重心以及关节角度特征,构建双向长短时记忆网络(Bidirectional Long Short-Term Memory Network,Bi-LSTM),并将上述特征输入该模型内,实现多运动目标异常行为识别。经实验验证得出,所提方法对红外图像的增强效果好,多目标异常行为的识别精度高。
