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A cross-type imaging electron spectrometer

Science China(Technological Sciences) 2023年第3期66卷 641-653页

作者： YE YuGuang ZOU Hong WANG YongFu QIN JunFeng SHI WeiHong ZOU JiQing zhong weiying ZONG QiuGang FU SuiYan School of Earth and Space Sciences Peking UniversityBeijing 100871China

Energetic electron measurement is of great significance to theoretical space physics research and space weather applications.Current energetic electron detectors must cooperate with a spin-stabilized satellite platform to achieve high angular resolution in pitch angle distribution and three-dimensional(3D)imaging measurement of energetic electrons.This article introduces a cross-type quasi-3D imaging electron spectrometer(IES)based on pinhole imaging technology developed in the laboratory.The imager is composed of five imaging units,including a nine-pixel area array Si-PIN detector imaging unit in the middle and four three-pixel linear array Si-PIN detector imaging units placed in a cross-shape around it.The combination of five imaging units forms two orthogonal nine-pixel linear array detectors(with a common pixel in the middle).There are four pixels with a view angle of 20°×20°in the 45°oblique directions of the cross-type detection array.There are 21 imaging pixels in the entire crosstype sensor head,corresponding to 21 directions.Two multichannel integrated preamplifier ASICs are integrated in the sensor head to realize particle signal readout from 21 pixels.With a back-end electronics system,each pixel can achieve high energy resolution detection of 50–600 keV electrons.Radioactive sources and electron accelerators are used to calibrate the cross-type imaging sensor head,and the results demonstrate its good energy and directional detection characteristics(the energy resolution reaches 6.9 keV for the incident 200 keV electron beam).We performed simulations on the imaging sensor head’s ability to measure the electron pitch angle distribution on the three-axis stabilized platform,and the results show that the sensor head can perform quasi-three-dimensional detection of electrons incident within 2πsolid angles on the three-axis stabilized satellite platform,with an average angular resolution of the electron pitch angle distribution of less than 6°.

关键词： energetic electron detection imaging electron spectrometer cross-type sensor head pitch angle distribution

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面向高光谱异常检测的背景记忆模型

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遥感学报 2024年第3期28卷 717-729页

作者：谢卫莹钟佳平李云松西安电子科技大学综合业务网理论及关键技术国家重点实验室西安710071

高光谱图像具有丰富的连续光谱信息,覆盖从可见光到红外波长范围内数百个波段。此数据特性使得高光谱数据在图像处理中有挖掘光谱内在特征的独特优势,从而有利于充分利用空间和光谱信息,检测感兴趣区域中的目标。但是由于高光谱数据的... 详细信息

高光谱图像具有丰富的连续光谱信息,覆盖从可见光到红外波长范围内数百个波段。此数据特性使得高光谱数据在图像处理中有挖掘光谱内在特征的独特优势,从而有利于充分利用空间和光谱信息,检测感兴趣区域中的目标。但是由于高光谱数据的高维性、实际场景的复杂性以及有标签样本数量的有限性,高光谱异常检测仍面临背景和异常不易区分和检测精度低的问题。为了解决以上问题,本文提出一种面向高光谱异常检测的背景记忆模型。首先,通过无监督的基于密度估计的粗检方法,获得伪背景和伪异常向量。其次,设计基于异常突出正则项约束的背景记忆生成对抗网络模型,扩大伪背景和伪异常间的距离,并采用弱监督—伪标签的训练方式,使得网络具有较强的背景生成能力,同时弱化其对于异常的重构效果,减少对于背景和异常重构的泛化性,增强输出检测结果中背景和异常的差异和辨别度。此外,在特征域和图像域进行对抗学习,提高样本生成能力,更好地学习到输入样本的分布情况,提高网络对背景的生成能力。最后,使用非线性背景抑制方法减小虚警率,进一步提升检测精度。实验结果表明,本文方法相比其他检测算法在不同数据集上具有更好的检测效果。

关键词：遥感生成对抗网络高光谱异常检测弱监督学习无监督学习

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基于深度学习的逆变器电路图像数据智能识别方法

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现代电子技术 2024年第10期47卷 139-142页

作者：何韦颖钟健谌颃广州理工学院计算机科学与工程学院广东广州510540 广州理工学院信息与网络中心广东广州510540 广州科技贸易职业学院信息工程学院广东广州511442

进行逆变器电路图像数据识别时,特征信息提取不充分使得无法准确捕捉到关键特征,导致识别精度下降。为此,提出一种基于深度学习的逆变器电路图像数据智能识别方法。首先,利用逆变器数据采集系统,采集逆变器电路图像数据。然后,将图像数... 详细信息

进行逆变器电路图像数据识别时,特征信息提取不充分使得无法准确捕捉到关键特征,导致识别精度下降。为此,提出一种基于深度学习的逆变器电路图像数据智能识别方法。首先,利用逆变器数据采集系统,采集逆变器电路图像数据。然后,将图像数据输入到卷积神经网络模型中,通过卷积核提取数据的特征。最后,采用YOLO算法对其进行有效识别,基于CA模块对特征信息进行关注,并利用Detect模块输出识别结果。Detect模块主要包括置信度函数和模型的损失函数,将两者结合,利用分类框和检测框来实现对逆变器电路图像的识别。实验结果表明,所提方法的识别误报率最高仅为6%,具有实用性。

关键词：深度学习逆变器电路图像识别数据特征提取卷积神经网络 YOLO算法

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Direct measurement of the linear energy transfer of ions in silicon for space application

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Science China(Technological Sciences) 2016年第1期59卷 128-134页

作者： CHEN HongFei YU XiangQian SHAO SiPei SHI WeiHong CUI ZhanGuo XIANG HongWen HAO ZhiHua ZOU JiQing zhong weiying ZOU Hong Institute of Space Physics and Applied Technology School of Earth and Space SciencesPeking UniversityBeijing 100871China Institute of Shandong Aerospace Technology Yantai 264003China China Academy of Space Technology Beijing 100094 China

The single event effect(SEE) is an important consideration in electronic devices used in space environments because it can lead to spacecraft anomalies and failures. The linear energy transfer(LET) of ions is commonly investigated in studies of SEE. The use of a thin detector is an economical way of directly measuring the LET in space. An LET telescope consists of a thin detector as the front detector(D1), along with a back detector that indicates whether D1 was penetrated. The particle radiation effect monitor(PREM) introduced in this paper is designed to categorize the LET into four bins of 0.2–0.4, 0.4–1.0, 1.0–2.0 and 2.0–20 Me V·cm^2/mg, and one integral bin of LET>20 Me V·cm^2/mg. After calibration with heavy ions and Geant4 analysis, the LET boundaries of the first four bins are determined to be 0.236, 0.479, 1.196, 2.254, and 17.551 Me V·cm^2/mg, whereas that of the integral bin is determined to be LET>14.790 Me V·cm^2/mg. The acceptances are calculated by Geant4 analysis as 0.452, 0.451, 0.476, 0.446, and 1.334, respectively. The LET accuracy is shown to depend on the thickness of D1; as D1 is made thinner, the accuracy of the measured values increases.

关键词：空间应用直接测量能量转移重离子线性单粒子效应 Geant4 探测器

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Variations of the relativistic electron flux after a magnetospheric compression event

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Science China(Technological Sciences) 2017年第4期60卷 638-647页

作者： CHEN Zhe CHEN HongFei LI YiFan XIANG HongWen YU XiangQian SHI WeiHong HAO ZhiHua ZOU Hong ZOU JiQing zhong weiying Institute of Space Physics and Applied Technology Peking University Beijing 100871 China School of Electronic and Information Engineering Beihang University Beijing 100191 China Beijing Institute of Spacecraft System Engineering Beijing 100094 China

On January 21, 2015, a sharp increase of the solar wind dynamic pressure impacted the magnetosphere. The magnetopause moved inward to the region L< 8 without causing a geomagnetic storm. The flux of the relativistic electrons in the outer radiation belt decreased by half during this event based on the observations of the particle radiation monitor(PRM) of the fourth of the China-Brazil Earth Resource Satellites(CBERS-4). The flux remained low for approximately 11 d; it did not recover after a small magnetic storm on January 26 but after a small magnetic storm on February 2. The loss and recovery of the relativistic electrons during this event are investigated using the PRM data, medium-and high-energy electron observations of NOAA-15 and the Van Allen Probes, medium-energy electron observations of GOES-13, and wave observations of the Van Allen Probes. This study shows that the loss of energetic electrons in this event is related to magnetospheric compression. The chorus waves accelerate the medium-energy electrons, which causes the recovery of relativistic electrons. The Van Allen Probes detected strong chorus waves in the region L =3–6 from January 21 to February 2. However, the flux of medium-energy electrons was low in the region. This implies that the long-lasting lack of recovery of the relativistic electrons after this event is due to the lack of the medium-energy"seed" electrons. The medium-energy electrons in the outer radiation belt may be a clue to predict the recovery of relativistic electrons.

关键词：相对论电子磁层顶事件通量压缩地球资源卫星高能电子辐射监测仪

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生态瞬时干预在健康行为促进中的应用进展

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护理学杂志 2024年第2期39卷 116-121页

作者：张祎徐岚潘习姚林仲伟莹李佳璇苏州大学附属第一医院护理部江苏苏州215006

介绍生态瞬时干预的概念、产生和发展、分类,综述生态瞬时干预在健康饮食、控制饮酒、戒烟、增强身体活动等健康行为促进中的应用,并对生态瞬时干预在健康行为促进中的应用提出建议,旨在为医护人员进一步开展健康行为干预提供参考。

关键词：生态瞬时干预健康行为即时适应性干预移动应用程序行为促进疾病预防综述文献

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基于数据挖掘的高校校友管理信息系统研究

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信息与电脑 2024年第6期36卷 86-88页

作者：何韦颖钟健陈有拾广州理工学院计算机科学与工程学院广东广州1510540

面对高校校友管理的多种属性资源信息,建构多层高校校友资源管理的信息化系统,设置涵盖数据字段名、字段类型、字段说明、备注等的数据库表,进行校友注册和访问、校友账号和密码恢复、校友属性信息、校友会活动、校友信息分类和存储等... 详细信息

面对高校校友管理的多种属性资源信息,建构多层高校校友资源管理的信息化系统,设置涵盖数据字段名、字段类型、字段说明、备注等的数据库表,进行校友注册和访问、校友账号和密码恢复、校友属性信息、校友会活动、校友信息分类和存储等系统化管理,为广大校友组织信息管理服务、校友活动提供支持。

关键词：数据挖掘高校信息系统

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Rational designed microstructure pressure sensors with highly sensitive and wide detection range performance

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Journal of Materials Science & Technology 2022年第35期130卷 184-192页

作者： Yimeng Ni Lexin Liu Jianying Huang Shuhui Li zhong Chen weiying Zhang Yuekun Lai College of Chemical Engineering Fuzhou UniversityFuzhou 350116China Department of Chemistry University College LondonLondonUK School of Materials Science and Engineering Nanyang Technological University50 Nanyang AvenueSingapore

Highly sensitive pressure sensors are often deployed in human-machine interaction area,touch screen and human motion detection.However,there are still great challenges to fabricating with high sensitivity pressure sensor with wide-range detection.Herein,we developed a new strategy to fabricate a highly sensitive pressure sensor using sandpaper and improve its detection range using a sacrificial template.It was the fthatirst time to combine microstructure processing with the sacrificial template method to fabricate pressure sensor.The microstructure of sandpaper endowed the sensor with high sensitivity,and the elastic substrate enhanced the sensor ability to resist high pressure without being damaged.The fabricated sensor device exhibits a superior sensitivity of 39.077 kPa-1in the range from 50 kPa to 110 kPa with a broad linear response.Remarkably,high pressure ceiling(<160 kPa) ensures that the sponge could be applied in different practical conditions to monitor a range of subtle human motions including finger,wrist bending,and pulse.For applications,the sensor device can not only detect the foot stepping behavior(0.7 MPa) but also produce an obvious response to an extremely slight paper(9 mg,~0.9 Pa).The successful preparation of this micro-structured elastic sponge material provided new ideas for exploring its potential applications in pressure sensors and flexible wearable electronic devices.

关键词： Pressure sensor High sensitivity Conductive sponge Template Micro-structure

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陕西省畜禽屠宰行业现状及发展对策

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畜牧兽医杂志 2024年第2期43卷 40-43页

作者：朱伟英李智强钟改玲陕西省动物卫生与屠宰管理站陕西西安710016 陕西省农业农村厅宝鸡市凤翔区商务局电子商务发展中心

为全面了解畜禽屠宰行业发展现状,笔者对陕西省畜禽屠宰企业进行调研,分析了畜禽屠宰行业和监管现状,指出了畜禽屠宰监管不充分、生猪屠宰整体发展不均衡、牛羊屠宰发展相对落后、家禽规范化屠宰实施难等问题,针对性提出了持续强化畜禽... 详细信息

为全面了解畜禽屠宰行业发展现状,笔者对陕西省畜禽屠宰企业进行调研,分析了畜禽屠宰行业和监管现状,指出了畜禽屠宰监管不充分、生猪屠宰整体发展不均衡、牛羊屠宰发展相对落后、家禽规范化屠宰实施难等问题,针对性提出了持续强化畜禽屠宰监管、促进生猪屠宰企业转型升级、统筹规划牛羊屠宰产业、尽快规范家禽屠宰管理等策略,以期为陕西省畜禽屠宰高质量发展提供参考。

关键词：畜禽屠宰行业现状发展对策

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Imaging energetic electron spectrometer onboard a Chinese navigation satellite in the inclined GEO orbit

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Science China(Technological Sciences) 2018年第12期61卷 1845-1865页

作者： ZOU Hong YE YuGuang ZONG QiuGang CHEN HongFei ZOU JiQing CHEN Jiang SHI WeiHong YU XiangQian zhong weiying WANG YongFu ZHOU XuZhi HAO YiXin CHEN XingRan JIA XiangHong XU Feng SHAO SiPei WANG Bo HAO XiaoYun ZHANG XiaoXin Institute of Space Physics and Applied Technology Peking University Beijing 100871 China State Key Laboratory of Space Medicine Fundamentals and Application Chinese Astronaut Research and Training Center Beijing 100094 China Shandong Aerospace Electro-technology Yantai 264000 China Key Laboratory of Space Weather National Center for Space Weather Beijing 100081 China

The energetic electron measurement is one of the most important issues to understand dynamics in space physics and the applications for space weather. In this study, the principle and functional components of the imaging energetic electron spectrometer(IES) onboard a Chinese navigation satellite in the inclined GEO orbit(IGSO) was introduced. The IES instrument is developed by the team in Peking University(BeiDa), thus it is named as BD-IES. Based on the pin-hole technique, the instrument can measure 50–600 keV electrons incident from 9 directions over a range of 180° in polar angle. With pulse height analysis(PHA), the spectrum can be determined for each direction. The energy and angular calibrations were performed, which show the good energy and angular characteristics of BD-IES. Monte Carlo simulations show that the anti-proton design of BDIES can effectively decrease the proton contamination on the electron measurements in the inclined GEO orbit. The primary results of BD-IES verify the successful design of this instrument.

关键词： imaging energetic electron spectrometer pin-hole imaging system IGSO satellite

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