A ten-month field research study was meticulously conducted at Robert Moses State Park (RMSP) on the south shore of Long Island, NY. The objective was to determine if aerial phenomena of an unknown nature exist over a...A ten-month field research study was meticulously conducted at Robert Moses State Park (RMSP) on the south shore of Long Island, NY. The objective was to determine if aerial phenomena of an unknown nature exist over a coastal location and to characterize their properties and behaviors. Primary and secondary field observation methods were utilized in this data-centric study. Forensic engineering principles and methodologies guided the study. The challenges set forward were object detection, observation, and characterization, where multispectral electro-optical devices and radar were employed due to limited visual acuity and intermittent presentation of the phenomena. The primary means of detection utilized a 3 cm X-band radar operating in two scan geometries, the X- and Y-axis. Multispectral electro-optical devices were utilized as a secondary means of detection and identification. Data was emphasized using HF and LF detectors and spectrum analyzers incorporating EM, ultrasonic, magnetic, and RF field transducers to record spectral data in these domains. Data collection concentrated on characterizing VIS, NIR, SWIR, LWIR, UVA, UVB, UVC, and the higher energy spectral range of ionizing radiation (alpha, beta, gamma, and X-ray) recorded by Geiger-Müller counters as well as special purpose semiconductor diode sensors.展开更多
高压直流输电系统嵌入大型交流系统,将进一步增加换相失败、直流闭锁等故障对系统安全稳定的影响,交流系统与直流系统的交互作用,将使系统动态更加复杂。针对电网不同运行方式下大扰动后系统复杂动态响应特性分析难题,文中提出一种基于...高压直流输电系统嵌入大型交流系统,将进一步增加换相失败、直流闭锁等故障对系统安全稳定的影响,交流系统与直流系统的交互作用,将使系统动态更加复杂。针对电网不同运行方式下大扰动后系统复杂动态响应特性分析难题,文中提出一种基于机电-电磁混合仿真与机器学习的智能分析方法。该方法基于主成分分析(principal components analysis,PCA)降维、基于密度的噪声应用空间聚类(density-based spatial clustering of applications with noise,DBSCAN)、K-means等算法建立二阶段聚类模型,可针对直流落点近区严重故障后大量混合仿真动态曲线在高维空间中自动聚类,并给出相应标识与严重程度;提取交直流系统在不同故障下的典型动态模式,自动标注并识别各模式下主导安全稳定问题。文中所提方法的有效性在2025年华东电网运行方式中得以验证,仿真结果表明,所提方法可有效提取不同故障下系统动态模式,将有效支撑后续复杂故障下的交直流系统动态机理分析。展开更多
矿井下常常存在地下水渗积问题,通过控制主泵出水压力,能够有效地排除积水,保持井下环境相对干燥,增强煤矿地下环境的安全性。但由于矿井下的透水后压力负荷通常是不确定的,单纯以压力为传感信号的主泵排水控制的稳定性会受到较大影响,...矿井下常常存在地下水渗积问题,通过控制主泵出水压力,能够有效地排除积水,保持井下环境相对干燥,增强煤矿地下环境的安全性。但由于矿井下的透水后压力负荷通常是不确定的,单纯以压力为传感信号的主泵排水控制的稳定性会受到较大影响,当前排水多以人工观测为主,排水控制智能化实现难度较大。提出一种扬程特性关联下矿井主泵排水智能控制方法。分析矿井下大功率变频式主泵的扬程特性(H-Q),获取变频式主泵排水压力和扬程特性(H-Q)之间的关系。利用这一关系作为传感信号,采用解耦补偿器和神经网络,利用神经网络在线调整比例、积分和微分(proportional integral derivative,PID)控制参数,组建大功率变频式主泵出水压力智能控制器,实现泵出水压力智能控制。通过实验分析证明,研究方法应用后在22 s左右矿井主泵达到最佳状态,过程中产生的相对误差均在0.5%以下。在多次迭代控制下,所提方法的控制延误始终低于0.1 ms。展开更多
文摘A ten-month field research study was meticulously conducted at Robert Moses State Park (RMSP) on the south shore of Long Island, NY. The objective was to determine if aerial phenomena of an unknown nature exist over a coastal location and to characterize their properties and behaviors. Primary and secondary field observation methods were utilized in this data-centric study. Forensic engineering principles and methodologies guided the study. The challenges set forward were object detection, observation, and characterization, where multispectral electro-optical devices and radar were employed due to limited visual acuity and intermittent presentation of the phenomena. The primary means of detection utilized a 3 cm X-band radar operating in two scan geometries, the X- and Y-axis. Multispectral electro-optical devices were utilized as a secondary means of detection and identification. Data was emphasized using HF and LF detectors and spectrum analyzers incorporating EM, ultrasonic, magnetic, and RF field transducers to record spectral data in these domains. Data collection concentrated on characterizing VIS, NIR, SWIR, LWIR, UVA, UVB, UVC, and the higher energy spectral range of ionizing radiation (alpha, beta, gamma, and X-ray) recorded by Geiger-Müller counters as well as special purpose semiconductor diode sensors.
文摘高压直流输电系统嵌入大型交流系统,将进一步增加换相失败、直流闭锁等故障对系统安全稳定的影响,交流系统与直流系统的交互作用,将使系统动态更加复杂。针对电网不同运行方式下大扰动后系统复杂动态响应特性分析难题,文中提出一种基于机电-电磁混合仿真与机器学习的智能分析方法。该方法基于主成分分析(principal components analysis,PCA)降维、基于密度的噪声应用空间聚类(density-based spatial clustering of applications with noise,DBSCAN)、K-means等算法建立二阶段聚类模型,可针对直流落点近区严重故障后大量混合仿真动态曲线在高维空间中自动聚类,并给出相应标识与严重程度;提取交直流系统在不同故障下的典型动态模式,自动标注并识别各模式下主导安全稳定问题。文中所提方法的有效性在2025年华东电网运行方式中得以验证,仿真结果表明,所提方法可有效提取不同故障下系统动态模式,将有效支撑后续复杂故障下的交直流系统动态机理分析。
文摘矿井下常常存在地下水渗积问题,通过控制主泵出水压力,能够有效地排除积水,保持井下环境相对干燥,增强煤矿地下环境的安全性。但由于矿井下的透水后压力负荷通常是不确定的,单纯以压力为传感信号的主泵排水控制的稳定性会受到较大影响,当前排水多以人工观测为主,排水控制智能化实现难度较大。提出一种扬程特性关联下矿井主泵排水智能控制方法。分析矿井下大功率变频式主泵的扬程特性(H-Q),获取变频式主泵排水压力和扬程特性(H-Q)之间的关系。利用这一关系作为传感信号,采用解耦补偿器和神经网络,利用神经网络在线调整比例、积分和微分(proportional integral derivative,PID)控制参数,组建大功率变频式主泵出水压力智能控制器,实现泵出水压力智能控制。通过实验分析证明,研究方法应用后在22 s左右矿井主泵达到最佳状态,过程中产生的相对误差均在0.5%以下。在多次迭代控制下,所提方法的控制延误始终低于0.1 ms。
