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Dating Fault Activity Based on Surface Texture of Quartz Grains from the Bailong River Fault

Acta Geologica Sinica(English Edition) 2014年第4期88卷 1131-1144页

作者： SHEN Junfeng YANG Weimin LIU Ting HUANG Xiao zheng weijie YU Lei WANG Guoqiang School of Earth Science and Resources China University of Geosciences Institute of Geomechanics Chinese Academy of Geological Sciences

Much important information referring to fault motion （e.g., fault activities period, intensity, frequency, and even dynamic background） can be revealed by resolving fault gouge, which is the result of fault motion while extruding or grinding. The field investigation encompassed sample collecting from the Bailong River fault system of the western segment of the Qinling Orogenic Belt （QOB）; 44 samples of fault gouges were collected for quartz micro-morphology analysis. These samples were analyzed using field emission scanning electron microscopy. In addition, 14 samples were tested for thermo-luminescence dating. The results showed that most of the surface textures of quartz grains are characterized by fish scale, moss-like texture, and stalactite. However, a small amount of orange peel-like fractures and worm-hole-like shaped surface texture were observed. Moreover, a few typical conchoids or subconchoidal fractures in quartz grains can be seen. This implies that the Bailong River Fault was active repeatedly during the Quaternary period, but the main motion period is the Pleistocene. The 14 thermo-luminescence dating values showed two age groups： 343.29-184.06 ka and 92.18-13.87 ka. These study data reveal that fault movement started during the Pliocene, occurred frequently in the early-middle period of the Pleistocene, and the peak frequency of the motion was reached in the early Pleistocene. The fault motions were stopped terminated in the early Holocene. The results are significant for the natural disaster risk evaluation in the western segment of the QOB.

关键词： fault gouge surface texture of quartz thermo-luminescence dating Pleistocene BailongRiver Fault

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Technology and engineering application of cross area HVDC interconnection system high-precision simulation modeling based on ADPSS

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Global Energy Interconnection 2018年第5期1卷 627-635页

作者： weijie zheng Jianfeng Yan Xujiang Chen Shuwen Xu Yalou Li China Electric Power Research Institute

In recent years, a large number of high voltage direct current(HVDC) transmission projects have been connected to AC systems. This has started to have an impact on AC/DC hybrid power grids, particularly receiving terminal power grids. An HVDC system is a large-scale power electronic integrated nonlinear system, and it includes a primary system and a control and protection system. Hence, the precision and degree of detail of HVDC systems directly affect the actual effect of simulation. In recent years, in the case of the normal operation and failure of AC power grids, the abnormal fluctuation and even locking of HVDC systems caused by the inappropriate strategies of the control and protection system component have strongly affected power grids. This has significantly affected the safety and stability of receiving power grids and normal operation. In this study, the actual engineering HVDC control logic provided by a manufacturer is analyzed and simulated based on the user defined component library of the ADPSS electromagnetic transient calculation program, and an HVDC control model based on an actual system is established. The accuracy of the DC control custom model based on ADPSS is verified through the simulation of an actual power grid.

关键词： ADPSS HVDC control and protection system Detailed electromagnetic transient simulation AC–DC large power grid system

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Pyrolysis of single carbon sources in SBA-15: A recyclable solid phase synthesis to obtain uniform carbon dots with tunable luminescence

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Chinese Chemical Letters 2023年第2期34卷 458-462页

作者： Xiaoqing Niu weijie zheng Tianbing Song Zunhui Huang Chunlei Yang Liming Zhang Wei Li Huanming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Most of carbon dots(CDs) are synthesized in solutions, but the extensive use of solvents produces too much waste, needs complex purification and results in low yield. Particularly for the popular hydrothermal/solvothermal syntheses, safety issues hinder the large-scale production of CDs. Solid phase synthesis in air seems perfect to solve the above problems once for all, but nanoparticle growth in solid phase is always difficult to control. Here we suggest a new method to synthesize CDs in SBA-15 template, just by heating single carbon sources in air. Employing single carbon sources is important, which ensures both homogeneity of the nucleation and uniformity of the nanoparticle growth. The pores confinement of SBA-15 guarantees the uniform sizes of CDs, while the catalytic effect of SBA-15 accelerates the carbonization process of precursors. The products are easily extracted from the template by ethanol, and then the template can be recycled for the next synthesis after calcination. Various CDs are synthesized in this way by using different carbon sources and SBA-15 templates with different pore diameters, respectively. The results show that, the fluorescence properties of these CDs are determined by their composition and surface states, but not the particle sizes. This work opens a new avenue to synthesize uniform CDs in solid phase with high yield, low cost and tunable luminescence.

关键词： Carbon dots Solid phase synthesis SBA-15 Luminescence Uniformity

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可控高抗分相抑制过电压和潜供电流的暂态控制方法和策略

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中国电机工程学报 2014年第19期34卷 3187-3193页

作者：郑伟杰中国电力科学研究院北京市海淀区100192

提出在超/特高压长输电线三相不平衡、单相接地和非全相运行等不对称情况下,采用可控高抗分相投切的控制策略来抑制非故障相过电压,改进了传统的全相调节方式,提高了电压稳定性和控制灵活度。为降低超/特高压线路潜供电流大小,改善单相... 详细信息

提出在超/特高压长输电线三相不平衡、单相接地和非全相运行等不对称情况下,采用可控高抗分相投切的控制策略来抑制非故障相过电压,改进了传统的全相调节方式,提高了电压稳定性和控制灵活度。为降低超/特高压线路潜供电流大小,改善单相重合闸条件,提出可控高抗分相调节下中性点电抗的联动控制方法,实验对比了不同控制策略的调控效果、验证了方法的有效性。

关键词：可控高抗潜供电流过电压中性点电抗

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基于Gaussian算法的高压直流平抗瓦斯非线性耦合动态特性精细化建模

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中国电机工程学报 2018年第2期38卷 637-643页

作者：郑伟杰国家电网仿真中心电网安全与节能国家重点实验室(中国电力科学研究院有限公司)

随着近几年来大量高压直流输电工程接入交流系统,给交直流混联电网带来重要影响,直流系统的运行状况,尤其是其控制保护系统的性能,已成为影响交直流混联电网安全稳定的重要因素。系统故障引发平波电抗器瓦斯保护误动作是导致直流系统闭... 详细信息

随着近几年来大量高压直流输电工程接入交流系统,给交直流混联电网带来重要影响,直流系统的运行状况,尤其是其控制保护系统的性能,已成为影响交直流混联电网安全稳定的重要因素。系统故障引发平波电抗器瓦斯保护误动作是导致直流系统闭锁的重要非电气量因素之一,该文详细研究分析了平抗瓦斯的设备原理和特点,采用Gaussian回归算法对平抗瓦斯机械振动与冲击电流的非线性耦合特性进行精细化模拟和解耦,且与电磁暂态算法相兼容,并基于国网仿真中心华东电网电力系统全数字实时仿真装置（advanced digital power system simulator,ADPSS）纯电磁暂态实际工程控保算例进行交直流电网纯电磁仿真,可以详细描述交直流电网故障冲击电流等电气量动态变化对平抗瓦斯机械振动加速度非电气量的非线性快速响应动态特性,为实际工程中多次发生的平抗瓦斯误动导致直流闭锁的事故分析和故障重演、预防及设备改进提供关键技术手段,对进一步提高直流实用化工程仿真的多维度精度具有重要现实意义,并为其他非线性电气相关设备的详细建模提供思路。

关键词：高压直流闭锁换相失败平抗瓦斯保护非电气量非线性动态特性

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电力系统大容量非线性元件动态差分修正跟踪控制算法

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中国电机工程学报 2014年第13期34卷 2172-2177页

作者：郑伟杰中国电力科学研究院北京市海淀区100192

新能源发电和灵活输配电设备的规模化投运,加剧了大电网的强非线性及动态特性,为提高系统控制的灵活可靠性,提出一种电力系统非线性元件的时变参数差分修正跟踪控制算法,以磁控高抗(magnetically controlled shunt reactor,MCSR)为例阐... 详细信息

新能源发电和灵活输配电设备的规模化投运,加剧了大电网的强非线性及动态特性,为提高系统控制的灵活可靠性,提出一种电力系统非线性元件的时变参数差分修正跟踪控制算法,以磁控高抗(magnetically controlled shunt reactor,MCSR)为例阐述算法的思路,控制目标是保持接入点线路电压稳定,抑制工频过电压,实现电压快速平滑调节,防止和减少系统振荡。针对外在电力系统与MCSR的相关性,对MCSR的非线性元件部分和外在系统的动态影响建立时变参数的曲线回归方程,映射换算后以解析解求出时变参数;采用时变参数差分法进行动态修正,提高了映射和跟踪的实时性和精确性。控制算法无需迭代,以MCSR为例在电力系统全数字实时仿真装置(advanced digital power system simulator,ADPSS)中搭建算例,算例结果验证了控制算法的有效性。算法有利于提高和改善电力系统非线性设备在电网中动态调控效果,也可为其他大容量非线性元件控制器的设计提供了思路。

关键词：大容量非线性元件动态相关分析系统辨识动态差分修正

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NEATmap: a high-efficiency deep learning approach for whole mouse brain neuronal activity trace mapping

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National Science Review 2024年第5期11卷 202-216页

作者： weijie zheng Huawei Mu Zhiyi Chen Jiajun Liu Debin Xia Yuxiao Cheng Qi Jing Pak-Ming Lau Jin Tang Guo-Qiang Bi Feng Wu Hao Wang AHU-IAI AI Joint Laboratory Anhui University Anhui Province Key Laboratory of Biomedical Imaging and Intelligent Processing Institute of Artificial IntelligenceHefei Comprehensive National Science Center National Engineering Laboratory for Brain-inspired Intelligence Technology and Application School of Information Science and TechnologyUniversity of Science and Technology of China Division of Life Sciences and Medicine University of Science and Technology of China Interdisciplinary Center for Brain Information Brain Cognition and Brain Disease InstituteShenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions Shenzhen Institute of Advanced Technology Chinese Academy of Sciences

Quantitative analysis of activated neurons in mouse brains by a specific stimulation is usually a primary step to locate the responsive neurons throughout the brain. However, it is challenging to comprehensively and consistently analyze the neuronal activity trace in whole brains of a large cohort of mice from many terabytes of volumetric imaging data. Here, we introduce NEATmap, a deep learning–based high-efficiency,high-precision and user-friendly software for whole-brain neuronal activity trace mapping by automated segmentation and quantitative analysis of immunofluorescence labeled c-Fos+neurons. We applied NEATmap to study the brain-wide differentiated neuronal activation in response to physical and psychological stressors in cohorts of mice.

关键词： whole-brain imagingneuronal activity trace mapping deep learning quantitative analysis

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Study on Characteristics of a High-Precision Cold Gas Micro Thruster

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Engineering（科研） 2024年第1期16卷 38-45页

作者： Zhaoli Wang Changbin Guan Xudong Wang weijie zheng Longfei Su Advanced Space Propulsion Lab Beijing Institute of Control Engineering Beijing China

In order to improve the reliability of the spacecraft micro cold gas propulsion system and realize the precise control of the spacecraft attitude and orbit, a micro-thrust, high-precision cold gas thruster is carried out, at the same time due to the design requirements of the spacecraft, this micro-thrust should be continuous working more than 60 minutes, the traditional solenoid valve used for the thrusts can’t complete the mission, so a long-life micro latching valve is developed as the control valve for this micro thruster, because the micro latching valve can keep its position when it cuts off the outage. Firstly, the authors introduced the design scheme and idea of the thruster. Secondly, the performance of the latching valve and the flow characteristics of the nozzle were simulated. Finally, from the experimental results and compared with the numerical study, it shows that the long-life micro cold gas thruster developed in this paper meets the mission requirements.

关键词： High-Precision Micro Thruster Performance Flow Characteristic Experiment

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Effects of interfacial buffering layer on imprint and domain switching dynamics in Pb(Zr,Ti)O_(3)thin-film heterostructures

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Journal of Advanced Dielectrics 2024年第3期14卷 51-57页

作者： Lingzhi Lu Chunyan zheng weijie zheng Chenyu Dong Yuhao Yue Yawen Xu zheng Wen College of Physics Qingdao University Qingdao Shandong 266071P.R.China College of Electronics and Information Qingdao University Qingdao Shandong 266071P.R.China

Interfacial engineering is important for ferroelectric thin-film heterostructures because of the modulation of boundary conditions of the spontaneous polarizations and their switching behaviors,which are essential for ferroelectric *** this work,we study the effects of interfacial buffering layer,5-nm-thick SrTiO_(3)(STO),on the imprint and domain switching of epitaxial Pt/Pb(Zr,Ti)O_(3)/SrRuO_(3)(SRO)thin-film heterostructures and *** buffering the ultrathin SrTiO_(3) layer at the Pb(Zr,Ti)O_(3)surface,the imprint effect can be dramatically alleviated as observed in the piezoresponse force microscopy(PFM)-measured domain structures and polarization–electric field hysteresis loops in thin-film ***,when the SrTiO_(3)layer is buffered at the Pb(Zr,Ti)O_(3)/SrRuO_(3)interface,the imprint effect is slightly *** phenomena are explained based on the band alignments among the Pt and SrRuO_(3)electrodes and the Pb(Zr,Ti)O_(3)layer associated with the existence of oxygen vacancies in the SrTiO_(3) *** the reduction of imprint effect,the domain switching dynamics are also improved in the SrTiO_(3)-buffered Pb(Zr,Ti)O_(3)capacitor,in which the switching activation field is decreased by about 45.3%in comparison with that of the pristine *** results facilitate the design and optimization of ferroelectric devices with the improvements in domain configurations,switching behaviors and band alignments.

关键词： Interfacial engineering heterostructures buffering switching polarizations

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磁控式并联电抗器动态自适应逆控制算法

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中国电机工程学报 2011年第19期31卷 1-7页

作者：郑伟杰周孝信中国电力科学研究院北京市海淀区100192

提出一种磁控式并联电抗器(magnetically controlled shunt reactor,MCSR)的非线性自适应逆控制系统的建模算法,采用"分解建模"的设计思想,将元件建模和动态系统辨识理论相结合,对MCSR的非线性元件部分和外在系统的动态影响分别建模。... 详细信息

提出一种磁控式并联电抗器(magnetically controlled shunt reactor,MCSR)的非线性自适应逆控制系统的建模算法,采用"分解建模"的设计思想,将元件建模和动态系统辨识理论相结合,对MCSR的非线性元件部分和外在系统的动态影响分别建模。建立描述非线性磁路特性的逆对象方程,根据"阿贝尔定理"对非线性方程进行泰勒展开,以解析解形式求出控制系统需要的励磁电流,建立逆对象传递函数;针对外在电力系统与MCSR的相关性,建立时变参数的动态回归方程,以最小二乘法求出时变参数。已在电力系统全数字实时仿真装置(advanced digital power systemsimulator,ADPSS)中编程实现了控制模块的工程化应用,并以MCSR实际运行参数搭建算例,验证了控制系统的有效性和实用性。

关键词：磁控式并联电抗器动态相关分析系统辨识非线性磁饱和特性反双曲函数自适应逆控制

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