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RF system of HIRFL-CSRe

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Science China(Physics,Mechanics & Astronomy) 2012年第1期55卷 44-47页

作者： XU Zhe WANG ChunXiao YI XiaoPing CONG Yan WEN LiangHua mei lirong JIN Peng XIA JiaWen ZHAO HongWei BIAN ZhiBin Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The operational frequency range of RF system at HIRFL-CSRe (cooling storage experimental ring) is 0.5-2 MHz, and it works in fundamental and second harmonic. It includes five sections: ferrite ring loaded RF cavity, RF generator, low-level system, computer system and cavity cooling. The cavity is based on the coaxial resonator type which is short at the terminal with one gap and loaded with domestic ferrite rings. The RF generator is designed in a push-pull mode. The low-level control system is based on PID, DSP, FPGA and DDS9854+USB interface and has three feedback loops. This RF system is designed independently and manufactured domestically. For the first time, it realized the pulse modulation, variable harmonic and CW operational modes. The maximum output power is up to 70 kW and the 10 kV RF voltage is used to capture the irradiative beam and decelerate the beam from 400 to 30 MeV/u.

关键词：射频系统射频发生器最大输出功率冷却储存二次谐波计算机系统 PID控制 USB接口

Design of an RFQ for direct plasma injection scheme

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Nuclear Science and Techniques 2009年第5期20卷 277-280页

作者： ZHANG Zhouli R.A. Jameson ZHAO Hongwei XU Zhe LIU Yong ZHANG Shenghu ZHANG Cong SUN Liepeng mei lirong SHEN Xiaokang Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institut far Angewandte Physik Goethe Universityat. Frankfurt D60438 Frankfurt-am-Main Germany

A high current radio frequency quadrupole (RFQ) is being studied at the Institute of Modern Physics, Chinese Academy of Sciences (IMP, CAS) for the direct plasma injection scheme (DPIS). Because of the strong space charge of beams from laser ion source, the beam dynamics design of the RFQ has been carried out with a new code, which can deal with space charge effectively. The design of the RFQ structure is performed with an electromagnetic simulation code and the determination of parameters of the structure has been done to maximize the shunt impedance when the frequency is kept fixed. The influences of dipole mode effect and flatness on beams were also discussed.

关键词：无电通信 RFQ IMP CAS

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基于密码的数据安全防护体系研究

信息安全与通信保密 2022年第9期20卷 48-56页

作者：梅莉蓉郭晓黎张小琼中国电子科技集团公司第三十研究所四川成都610041

数据已成为数字经济时代最核心、最具价值的生产要素,为全球经济增长不断注入新动力、新能量。随着数据利用的不断深入,数据规模不断扩大,数据泄露、滥用等风险日益凸显,亟需建设数据安全防护能力,防范数据安全风险,护航数字经济发展。... 详细信息

数据已成为数字经济时代最核心、最具价值的生产要素,为全球经济增长不断注入新动力、新能量。随着数据利用的不断深入,数据规模不断扩大,数据泄露、滥用等风险日益凸显,亟需建设数据安全防护能力,防范数据安全风险,护航数字经济发展。密码是保护数据安全的关键技术手段,在建立网络主体身份体系,确保数据机密性、完整性,促进数据流通等方面起到核心支撑作用。梳理了近期发布的数据安全相关法律法规中的密码要求,重点分析了数据全生命周期中密码发挥的核心作用,提出了基于密码的数据安全防护体系,并探讨了未来的研究方向和面临的挑战。

关键词：数据安全密码技术数据全生命周期新型密码算法

Low Level Control System of CSRe

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近代物理研究所和兰州重离子加速器实验室年报：英文版 2008年第1期 147-148页

作者： Wang Chunxaio Xu Zhe Yi Xiaoping Cong Yan mei lirong Shen Xiaokang Zhang Cong

阴道填塞磷化铝片剂中毒致多脏器功能衰竭并死亡1例

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职业卫生与应急救援 2024年第3期42卷 413-415页

作者：刘丽容杨梅王欣重庆医药高等专科学校附属第一医院重庆400060

磷化铝是一种广谱性熏蒸杀虫剂和灭鼠剂,在干燥条件下较稳定。磷化铝(氢)中毒症状轻重不一,口服中毒者症状多较重,严重者几小时内即可出现难治性低血压和严重代谢性酸中毒。报道了1例因“阴道瘙痒”自行在阴道内填塞质量分数为56%的磷... 详细信息

磷化铝是一种广谱性熏蒸杀虫剂和灭鼠剂,在干燥条件下较稳定。磷化铝(氢)中毒症状轻重不一,口服中毒者症状多较重,严重者几小时内即可出现难治性低血压和严重代谢性酸中毒。报道了1例因“阴道瘙痒”自行在阴道内填塞质量分数为56%的磷化铝片剂1片而导致中毒的34岁病例,患者病情进展快,中毒后数分钟后即出现恶心、呕吐等消化道症状,出现难治性低血压、严重代谢性酸中毒、呼吸窘迫、多脏器功能衰竭、反复发作恶性心律失常,虽经积极治疗,依旧在入院约43 h后死亡。提示应对民众加强卫生健康知识宣教,忌盲目听信“偏方”“秘方”,以免造成不必要的伤害。

关键词：磷化铝中毒阴道填塞多脏器功能衰竭难治性低血压代谢性酸中毒分布性休克

基于PPG信号的极简特征回归树血压估计模型设计

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中国医学物理学杂志 2024年第6期41卷 769-775页

作者：李勋刘丽荣李浩杨怜琳王志敏邹梅昆明学院物理科学与技术学院云南昆明650214 昆明学院医学院云南昆明650214 昆明市延安医院云南昆明650051

目的:提出一种基于光电容积脉搏波(PPG)的极简特征回归树血压估计模型。方法:从单路PPG信号中提取15个特征参数,利用斯皮尔曼相关系数筛选与血压相关性最高的4个参数,构建极简特征回归树血压模型。结果:极简特征回归树血压模型收缩压和... 详细信息

目的:提出一种基于光电容积脉搏波(PPG)的极简特征回归树血压估计模型。方法:从单路PPG信号中提取15个特征参数,利用斯皮尔曼相关系数筛选与血压相关性最高的4个参数,构建极简特征回归树血压模型。结果:极简特征回归树血压模型收缩压和舒张压的估计误差分别达到(-0.02±3.63)mmHg和(-0.04±2.10)mmHg。结论:提出的极简特征回归树血压模型结构简洁、准确率较高,这一发现对于在可穿戴设备中使用单路PPG信号进行血压估计具有重要意义。

关键词：光电容积脉搏波极简特征斯皮尔曼相关系数血压估计模型

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圆环共形重叠阵发射多波束形成算法研究

电子测量技术 2021年第11期44卷 125-130页

作者：赵柯刘丽哲梅立荣中国电子科技集团公司第五十四研究所石家庄050081

针对非重叠固定扇区波束形成指向模糊,主瓣增益低以及旁瓣较高等问题,设计了一种应用于圆环共形的重叠阵算法。该算法将圆阵划分为多个120°互相重叠的扇区,扇区数量和重叠区域可调整,同时采用有向阵元和Taylor加权,使得期望方向发射波... 详细信息

针对非重叠固定扇区波束形成指向模糊,主瓣增益低以及旁瓣较高等问题,设计了一种应用于圆环共形的重叠阵算法。该算法将圆阵划分为多个120°互相重叠的扇区,扇区数量和重叠区域可调整,同时采用有向阵元和Taylor加权,使得期望方向发射波束位于所划分扇区中心区域,获得最大增益。结果显示,与固定扇区非重叠圆阵相比,重叠圆阵发射单波束旁瓣抑制由-10.16dB下降至-21.2dB;发射两波束旁瓣抑制由-18.92dB下降至-24.18dB,主瓣增益由10.76dB上升至15.32dB;发射八波束时各波束主瓣指向精准无偏移且副瓣较低。结果表明,相对于传统固定阵波束形成算法,重叠阵算法在主瓣指向、主瓣增益及副瓣抑制等方面表现更加优良。

关键词：圆环共形重叠阵 Taylor加权多波束

Exploring impact of street layout on urban flood risk of people and vehicles under extreme rainfall based on numerical experiments

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中国科学:技术科学英文版 2023年第9期66卷 2561-2574页

作者： mei Chao LIU JiaHong SHI HongYuan WANG Hao WANG Jia DONG lirong SONG TianXu ZHANG HaiJia State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Key Laboratory of River Basin Digital Twinning of Ministry of Water Resources(Preparation) Beijing 100038China Beijing Key Laboratory of Urban Water Cycle and Sponge City Technology Beijing Normal UniversityBeijing 100875China

Urban street layout is an important factor in the formation process, characteristics, and risk level of urban flooding;therefore, this study numerically investigates the impact of street layout on urban flood risk to people and vehicles. Four typical street-layout scenarios with areas of 3 km × 3 km are established based on a block-scale investigation. The layout types are regular grid,irregular grid, radial, and annular. Urban inundation models are then constructed for these typical street layouts based on the twodimensional(2D) hydrodynamic method. Two historic, extreme rainfall events, which occurred in Beijing on July 21, 2012 and in Zhengzhou on July 20, 2021, are used as rainstorm scenarios for urban inundation modelling. The flood risks to people and vehicles are then calculated. Results show that, for an extreme rainstorm on the block scale, the street layout impacts the spatial and temporal distributions of the inundation variables, which include the water depth, flow velocity, flood volume, and inundated area. Moreover, for the same extreme-rainfall scenario, the greatest differences in the total flood volume, maximum street-water depth, and maximum street-flow velocity caused by street-layout differences are 17.22%, 60.25%, and 61.50%, respectively.Among the four street layouts considered in this study, the annular street layout exhibits the lowest degrees of inundation and flood risk. For the same extreme-rainfall scenario, the proportions of high-risk road sections for adults and children in this layout are 58.89% and 62.28% smaller than those for the layout with the largest proportion of high-risk road sections, respectively;the proportions of high-risk road sections for the Honda Accord and Audi Q7 were 55.31% and 53.04% smaller, respectively. The findings of this study may aid scientific understanding and development of “flood-sensitive” block-scale street layouts and urban planning in the context of the changing environment.

关键词： urban inundation street layout urban form flood risk hydrodynamic simulation

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基于数字超表面的低剖面波束控制天线

电波科学学报 2021年第6期36卷 938-946页

作者：盛丽丽曹卫平梅立荣张顺岚林艺香陆路聪桂林电子科技大学广西无线宽带通信与信号处理重点实验室桂林541004 桂林航天工业学院桂林541004 中国电子科技集团公司第五十四研究所石家庄050081 通信网信息传输与分发技术重点实验室石家庄050081

针对现有透射型超表面剖面高、难以可重构以及波束控制天线体积大的问题,提出一种基于单层数字超表面的波束偏转和宽窄波束切换天线实现方案.数字超表面由5×7个双方环单元构成,通过在双方环单元中放置一个PIN二极管实现1比特的数字编码... 详细信息

针对现有透射型超表面剖面高、难以可重构以及波束控制天线体积大的问题,提出一种基于单层数字超表面的波束偏转和宽窄波束切换天线实现方案.数字超表面由5×7个双方环单元构成,通过在双方环单元中放置一个PIN二极管实现1比特的数字编码.馈源天线采用具有寄生条带的微带背馈结构,数字超表面置于天线上方0.096λ0的高度,通过控制每一列PIN二极管的偏置电压实现对天线波束的操控.天线实测结果表明:在中心工作频率3.6 GHz处,波束偏转范围为0°~±45°;窄波束时增益8.5 dBi,宽波束时增益6.7 dBi,同时宽波束天线的3 dB波束宽度约为窄波束天线的两倍,测试结果与仿真结果吻合较好.该天线具有低剖面多功能特点,可应用在车载通信和机载通信等多个领域.

关键词：数字编码超表面低剖面波束控制微带天线