The plutonic rocks of the westernmost part of the Sirwa massif belong to the Ediacaran post-collisional magmatic chain of the Anti-Atlas.The geochemistry of major and trace elements attests that the fractional crystal...The plutonic rocks of the westernmost part of the Sirwa massif belong to the Ediacaran post-collisional magmatic chain of the Anti-Atlas.The geochemistry of major and trace elements attests that the fractional crystallization cannot account for the variations between the granitoids and the associated MME.They represent two contemporaneous but independent magmatic tendencies.However,Sr and Nd configur data argue for a similar and juvenile material展开更多
To eliminate the aliasing that appeared during the measurement of multi-components nonstationary signals, a novel kind of anti-aliasing algorithm based on the short time Fourier transform （STFT） is brought forward. ...To eliminate the aliasing that appeared during the measurement of multi-components nonstationary signals, a novel kind of anti-aliasing algorithm based on the short time Fourier transform （STFT） is brought forward. First the physical essence of aliasing that occurs is analyzed; second the interpolation algorithm model is setup based on the Hamming window; then the fast implementation of the algorithm using the Newton iteration method is given. Using the numerical simulation the feasibility of algorithm is validated. Finally, the electrical circuit experiment shows the practicality of the algorithm in the electrical engineering.展开更多
A novel space-borne antenna adaptive anti-jamming method based on the genetic algorithm （GA）, which is combined with gradient-like reproduction operators is presented, to search for the best weight for pattern synth...A novel space-borne antenna adaptive anti-jamming method based on the genetic algorithm （GA）, which is combined with gradient-like reproduction operators is presented, to search for the best weight for pattern synthesis in radio frequency （RF）. Combined, the GA＇s the capability of the whole searching is, but not limited by selection of the initial parameter, with the gradient algorithm＇s advantage of fast searching. The proposed method requires a smaller sized initial population and lower computational complexity. Therefore, it is flexible to implement this method in the real-time systems. By using the proposed algorithm, the designer can efficiently control both main-lobe shaping and side-lobe level. Simulation results based on the spot survey data show that the algorithm proposed is efficient and feasible.展开更多
Heuristic optimization methods provide a robust and efficient approach to solving complex optimization problems.This paper presents a hybrid optimization technique combining two heuristic optimization methods,artifici...Heuristic optimization methods provide a robust and efficient approach to solving complex optimization problems.This paper presents a hybrid optimization technique combining two heuristic optimization methods,artificial immune system（AIS） and particle swarm optimization（PSO）,together in searching for the global optima of nonlinear functions.The proposed algorithm,namely hybrid anti-prematuration optimization method,contains four significant operators,i.e.swarm operator,cloning operator,suppression operator,and receptor editing operator.The swarm operator is inspired by the particle swarm intelligence,and the clone operator,suppression operator,and receptor editing operator are gleaned by the artificial immune system.The simulation results of three representative nonlinear test functions demonstrate the superiority of the hybrid optimization algorithm over the conventional methods with regard to both the solution quality and convergence rate.It is also employed to cope with a real-world optimization problem.展开更多
在“三跨”输电线路张力放线施工中,一旦发生事故被牵导线可能跌落冲击下方跨越网,威胁被跨越物的安全稳定运行,因此提出一种基于激光点云与建筑信息模型(building information modeling,BIM)技术的“三跨”施工跨越网动力学响应分析方...在“三跨”输电线路张力放线施工中,一旦发生事故被牵导线可能跌落冲击下方跨越网,威胁被跨越物的安全稳定运行,因此提出一种基于激光点云与建筑信息模型(building information modeling,BIM)技术的“三跨”施工跨越网动力学响应分析方法。首先利用机载激光雷达采集“三跨”施工现场的三维点云数据,使用改进的布料模拟滤波算法分割得到跨越地形点云数据,使用基于点云空间维度特征与K-Means算法实现对跨越档两侧杆塔点云数据的高精度提取;其次根据提取的点云数据结合BIM技术对目标设备及施工环境进行逆向建模,通过不同地表物体的组装堆砌,并在其上搭建施工跨越网模型;最后通过模拟事故发生时导线对跨越网的冲击碰撞,探测跨越网的承载性能及其与被跨越物之间的动态净空距离。结果表明,该方法能够提前在实际施工环境中对跨越网的动力学性能进行分析,为输电线路跨越施工提供可靠的安全保障及数据支撑,具有一定的工程价值。展开更多
文摘The plutonic rocks of the westernmost part of the Sirwa massif belong to the Ediacaran post-collisional magmatic chain of the Anti-Atlas.The geochemistry of major and trace elements attests that the fractional crystallization cannot account for the variations between the granitoids and the associated MME.They represent two contemporaneous but independent magmatic tendencies.However,Sr and Nd configur data argue for a similar and juvenile material
基金the National Natural Science Foundation of China (90407007 60372001).
文摘To eliminate the aliasing that appeared during the measurement of multi-components nonstationary signals, a novel kind of anti-aliasing algorithm based on the short time Fourier transform （STFT） is brought forward. First the physical essence of aliasing that occurs is analyzed; second the interpolation algorithm model is setup based on the Hamming window; then the fast implementation of the algorithm using the Newton iteration method is given. Using the numerical simulation the feasibility of algorithm is validated. Finally, the electrical circuit experiment shows the practicality of the algorithm in the electrical engineering.
基金the National Natural Science Foundation of China (60502045).
文摘A novel space-borne antenna adaptive anti-jamming method based on the genetic algorithm （GA）, which is combined with gradient-like reproduction operators is presented, to search for the best weight for pattern synthesis in radio frequency （RF）. Combined, the GA＇s the capability of the whole searching is, but not limited by selection of the initial parameter, with the gradient algorithm＇s advantage of fast searching. The proposed method requires a smaller sized initial population and lower computational complexity. Therefore, it is flexible to implement this method in the real-time systems. By using the proposed algorithm, the designer can efficiently control both main-lobe shaping and side-lobe level. Simulation results based on the spot survey data show that the algorithm proposed is efficient and feasible.
文摘Heuristic optimization methods provide a robust and efficient approach to solving complex optimization problems.This paper presents a hybrid optimization technique combining two heuristic optimization methods,artificial immune system（AIS） and particle swarm optimization（PSO）,together in searching for the global optima of nonlinear functions.The proposed algorithm,namely hybrid anti-prematuration optimization method,contains four significant operators,i.e.swarm operator,cloning operator,suppression operator,and receptor editing operator.The swarm operator is inspired by the particle swarm intelligence,and the clone operator,suppression operator,and receptor editing operator are gleaned by the artificial immune system.The simulation results of three representative nonlinear test functions demonstrate the superiority of the hybrid optimization algorithm over the conventional methods with regard to both the solution quality and convergence rate.It is also employed to cope with a real-world optimization problem.
文摘在“三跨”输电线路张力放线施工中,一旦发生事故被牵导线可能跌落冲击下方跨越网,威胁被跨越物的安全稳定运行,因此提出一种基于激光点云与建筑信息模型(building information modeling,BIM)技术的“三跨”施工跨越网动力学响应分析方法。首先利用机载激光雷达采集“三跨”施工现场的三维点云数据,使用改进的布料模拟滤波算法分割得到跨越地形点云数据,使用基于点云空间维度特征与K-Means算法实现对跨越档两侧杆塔点云数据的高精度提取;其次根据提取的点云数据结合BIM技术对目标设备及施工环境进行逆向建模,通过不同地表物体的组装堆砌,并在其上搭建施工跨越网模型;最后通过模拟事故发生时导线对跨越网的冲击碰撞,探测跨越网的承载性能及其与被跨越物之间的动态净空距离。结果表明,该方法能够提前在实际施工环境中对跨越网的动力学性能进行分析,为输电线路跨越施工提供可靠的安全保障及数据支撑,具有一定的工程价值。
