Located on the mountainous area, Kelok Sembilan flyover area in West Sumatra, Indonesia has a long history of land deformation, therefore monitoring and analyzing as continuously is a necessity to minimize the impact....Located on the mountainous area, Kelok Sembilan flyover area in West Sumatra, Indonesia has a long history of land deformation, therefore monitoring and analyzing as continuously is a necessity to minimize the impact. Notably, in the rainy season, the land deformation occurs along this area. The zone is crucial as the center of transportation connection in the middle of Sumatra. Quasi-Persistent Scatterer (Q-PS) Interferometry technique was applied for extracting information of land deformation on the field from time to time. Not only does the method have high performance for detecting land deformation but also improve the number of PS point, especially in a non-urban area. This research supported by 90 scenes of Sentinel-1A (C-band) taken from October 2014 to November 2017 for ascending and descending orbit with VV and VH polarization in 5 × 20 m (range × azimuth) resolution. Both satellite orbits detected two critical locations of land deformation namely as zone A and Zone B, which located in positive steep slope where there is more than 500 mm movement in the Line of Sight (LOS) during acquisition time. Deformations in the vertical and horizontal direction for both zone, are 778.9 mm, 795.7 mm and 730.5 mm, 751.7 mm, respectively. Finally, the results were confirmed by ground truth data using Unmanned Aerial Vehicle (UAV) observation.展开更多
In this paper, we introduce a new way to obtain the Q-P （P-Q） ordering of quantum mechanical operators, i.e., from the classical correspondence of Q-P （P-Q） ordered operators by replacing q and p with coordinate a...In this paper, we introduce a new way to obtain the Q-P （P-Q） ordering of quantum mechanical operators, i.e., from the classical correspondence of Q-P （P-Q） ordered operators by replacing q and p with coordinate and momentum operators, respectively. Some operator identities are derived concisely. As for its applications, the single （two-） mode squeezed operators and Fresnel operator are examined. It is shown that the classical correspondence of Fresnel operator’s Q-P （P-Q） ordering is just the integration kernel of Fresnel transformation. In addition, a new photo-counting formula is constructed by the Q-P ordering of operators.展开更多
大规模风电接入电网给电网安全运行和管理带来了较大的挑战,新的电网导则要求风电机组应保证具备低电压穿越能力。考虑到动态电压恢复器(Dynamic Voltage Restorer,DVR)具有在短时间内快速准确进行电压补偿的优势,提出了基于动态电压恢...大规模风电接入电网给电网安全运行和管理带来了较大的挑战,新的电网导则要求风电机组应保证具备低电压穿越能力。考虑到动态电压恢复器(Dynamic Voltage Restorer,DVR)具有在短时间内快速准确进行电压补偿的优势,提出了基于动态电压恢复器的风电机组低电压穿越方案。针对DVR中滤波器带来的检测延时和衰减,采用基于瞬时无功功率理论的积分检测法,降低滤波器带来的延迟和衰减。根据DVR的控制特性,提出一种基于坐标变换的双Q-P理论的DVR控制算法,该算法可以补偿瞬时电压扰动,并且能有效改善动态电压恢复器的补偿性能。利用PSCAD/EMTDC仿真软件建立仿真模型,仿真结果表明,电网发生短路故障时,DVR能快速检测电压变化并且准确补偿所需电压,获得理想的瞬态特性,协助改善风电机组的低电压穿越性能。展开更多
文摘Located on the mountainous area, Kelok Sembilan flyover area in West Sumatra, Indonesia has a long history of land deformation, therefore monitoring and analyzing as continuously is a necessity to minimize the impact. Notably, in the rainy season, the land deformation occurs along this area. The zone is crucial as the center of transportation connection in the middle of Sumatra. Quasi-Persistent Scatterer (Q-PS) Interferometry technique was applied for extracting information of land deformation on the field from time to time. Not only does the method have high performance for detecting land deformation but also improve the number of PS point, especially in a non-urban area. This research supported by 90 scenes of Sentinel-1A (C-band) taken from October 2014 to November 2017 for ascending and descending orbit with VV and VH polarization in 5 × 20 m (range × azimuth) resolution. Both satellite orbits detected two critical locations of land deformation namely as zone A and Zone B, which located in positive steep slope where there is more than 500 mm movement in the Line of Sight (LOS) during acquisition time. Deformations in the vertical and horizontal direction for both zone, are 778.9 mm, 795.7 mm and 730.5 mm, 751.7 mm, respectively. Finally, the results were confirmed by ground truth data using Unmanned Aerial Vehicle (UAV) observation.
基金Project supported by the National Natural Science Foundation of China(Grant No.11264018)the Natural Science Foundation of Jiangxi Province of China(Grant No.20132BAB212006)the Fund from the Key Laboratory of Optoelectronics and Telecommunication of Jiangxi Province,China
文摘In this paper, we introduce a new way to obtain the Q-P （P-Q） ordering of quantum mechanical operators, i.e., from the classical correspondence of Q-P （P-Q） ordered operators by replacing q and p with coordinate and momentum operators, respectively. Some operator identities are derived concisely. As for its applications, the single （two-） mode squeezed operators and Fresnel operator are examined. It is shown that the classical correspondence of Fresnel operator’s Q-P （P-Q） ordering is just the integration kernel of Fresnel transformation. In addition, a new photo-counting formula is constructed by the Q-P ordering of operators.
文摘大规模风电接入电网给电网安全运行和管理带来了较大的挑战,新的电网导则要求风电机组应保证具备低电压穿越能力。考虑到动态电压恢复器(Dynamic Voltage Restorer,DVR)具有在短时间内快速准确进行电压补偿的优势,提出了基于动态电压恢复器的风电机组低电压穿越方案。针对DVR中滤波器带来的检测延时和衰减,采用基于瞬时无功功率理论的积分检测法,降低滤波器带来的延迟和衰减。根据DVR的控制特性,提出一种基于坐标变换的双Q-P理论的DVR控制算法,该算法可以补偿瞬时电压扰动,并且能有效改善动态电压恢复器的补偿性能。利用PSCAD/EMTDC仿真软件建立仿真模型,仿真结果表明,电网发生短路故障时,DVR能快速检测电压变化并且准确补偿所需电压,获得理想的瞬态特性,协助改善风电机组的低电压穿越性能。
