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BELLHOP3D模型的多核并行及性能评估

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声学技术 2024年第4期43卷 468-473页

作者：蓝强马树青朴胜春肖汶斌王勇献国防科技大学气象海洋学院湖南长沙410073 哈尔滨工程大学水声技术重点实验室黑龙江哈尔滨150001 哈尔滨工程大学海洋信息获取与安全工信部重点实验室工业和信息化部黑龙江哈尔滨150001 哈尔滨工程大学水声工程学院黑龙江哈尔滨150001

通过三维射线模型BELLHOP3D能够计算海洋中的三维声场,在声呐性能预报以及海洋环境参数反演等应用中具有重要意义。然而随着计算海域范围的增大以及计算网格点分辨率的提高,水声传播对计算的需求也逐渐增大。文章面向天河2号超级计算平... 详细信息

通过三维射线模型BELLHOP3D能够计算海洋中的三维声场,在声呐性能预报以及海洋环境参数反演等应用中具有重要意义。然而随着计算海域范围的增大以及计算网格点分辨率的提高,水声传播对计算的需求也逐渐增大。文章面向天河2号超级计算平台的多核体系结构,针对BELLHOP3D计算特征,充分挖掘其中的并行性,采用OpenMP多核并行技术,实现BELLHOP3D的多核并行。最后,通过Munk波导算例以及三维楔形海底算例对射线模型的并行计算效率进行了测试,当计算节点中的24个计算核心全部用于计算时,两个算例的并行计算效率分别达到了83.3%和87.5%。

关键词： BELLHOP3D 声呐性能预报天河2号 OpenMP多核并行并行效率

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黎曼流形下的水声测地线程函方程

声学技术 2024年第3期43卷 318-322页

作者：郭肖晋马树青张理论蓝强黄创霞国防科技大学气象海洋学院湖南长沙410073 长沙理工大学数学与统计学院湖南长沙410114

介质的天然非均匀性和时变等因素决定了水声传播信道是弯曲的黎曼流形。文章基于黎曼几何理论给出了水声射线程函方程在黎曼流形上的广义形式,该形式对于欧氏空间仍然适用。通过比较介质均匀的平面与弯曲球面两种理想场景,揭示了欧氏空... 详细信息

介质的天然非均匀性和时变等因素决定了水声传播信道是弯曲的黎曼流形。文章基于黎曼几何理论给出了水声射线程函方程在黎曼流形上的广义形式,该形式对于欧氏空间仍然适用。通过比较介质均匀的平面与弯曲球面两种理想场景,揭示了欧氏空间与弯曲流形上声传播存在差异。基于测地线程函方程和Bellhop-3D模式的Munk声速剖面射线仿真结果基本一致,验证了文中理论的正确性。文中结果为进一步开展弯曲水声信道的建模与计算奠定了概念基础。

关键词：黎曼度规测地线程函方程

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支气管扩张合并诺卡菌感染1例

国际医药卫生导报 2024年第12期30卷 2056-2058页

作者：李丹毕艳妮马淑青薛明山东大学附属威海市立医院中心实验室威海264200 山东大学附属威海市立医院介入科威海264200

本文报道了山东大学附属威海市立医院1例支气管扩张合并诺卡菌感染的病例,同时进行了相关文献复习。该患者为一名68岁的女性,被诊断为支气管扩张,细菌培养中发现呼吸道样本中存在诺卡菌。经过详细的临床和实验室评估,最后确诊为诺卡菌... 详细信息

本文报道了山东大学附属威海市立医院1例支气管扩张合并诺卡菌感染的病例,同时进行了相关文献复习。该患者为一名68岁的女性,被诊断为支气管扩张,细菌培养中发现呼吸道样本中存在诺卡菌。经过详细的临床和实验室评估,最后确诊为诺卡菌感染。在治疗过程中,患者接受了第三代头孢菌素联合复方磺胺甲噁唑片治疗方案,取得了良好的疗效。本案例强调了认识支气管扩张合并诺卡菌感染的重要性,临床医生需加深对诺卡菌病临床特征、流行病学、治疗方案以及预后情况的理解,检验医生应提升病原学的检测水平,提高诺卡菌检测的灵敏度。

关键词：支气管扩张诺卡菌肺部感染

A New X-band Weather Radar System with Distributed Phased-Array Front-ends: Development and Preliminary Observation Results

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Advances in Atmospheric Sciences 2022年第3期39卷 386-402页

作者： Xiaoqiong ZHEN shuqing ma Hongbin CHEN Guorong WANG Xiaoping XU Siteng LI Meteorological Observation Center of China Meteorological Administration Beijing 100081China College of Electronic Engineering Chengdu University of Information TechnologyChengdu 610225China Institute of Atmospheric Physics China Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences(CEPS) University of Chinese Academy of Sciences(UCAS)Beijing 100049China Eastone Washon Science and Technology Ltd. Changsha 410000China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China

A novel weather radar system with distributed phased-array front-ends was developed. The specifications and preliminary data synthesis of this system are presented, which comprises one back-end and three or more front-ends. Each front-end, which utilizes a phased-array digital beamforming technology, sequentially transmits four 22.5°-width beams to cover the 0°–90° elevational scan within about 0.05 s. The azimuthal detection is completed by one mechanical scan of0°–360° azimuths within about 12 s volume-scan update time. In the case of three front-ends, they are deployed according to an acute triangle to form a fine detection area(FDA). Because of the triangular deployment of multiple phased-array front-ends and a unique synchronized azimuthal scanning(SAS) rule, this new radar system is named Array Weather Radar(AWR). The back-end controls the front-ends to scan strictly in accordance with the SAS rule that assures the data time differences(DTD) among the three front-ends are less than 2 s for the same detection point in the FDA. The SAS can maintain DTD mallest DTD, gridded wind fields are derived from AWR data, by sampling of the interpolated grid, onto a rectangular grid of 100 m ×100 m ×100 m at a 12 s temporal resolution in the FDA. The first X-band single-polarized three-front-end AWR was deployed in field experiments in 2018 at Huanghua International Airport, China. Having completed the data synthesis and processing, the preliminary observation results of the first AWR are described herein.

关键词： phased-array weather radar multiple radar front-ends synchronized azimuthal scanning(SAS) data time differences(DTD) wind fields

基于理论-经验模型的春玉米产量丰歉动态气象评估

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气象与环境科学 2024年第2期47卷 86-93页

作者：张婷赵明马树庆李晓爽王晓炜王会军院士吉林省工作站长春130030 南信北大数据应用研究院(吉林省)有限公司长春130030 吉林省中农阳光数据有限公司长春130030 吉林省气象服务中心长春130062

为了在玉米不同生长阶段进行气象要素影响评价和产量丰歉趋势定量评估,利用1983—2018年吉林省50个气象观测站4—9月逐日降水量、气温和风速等资料,以及各县逐年玉米产量资料,基于春玉米生长发育自然节律和模糊数学原理,将吉林省春玉米... 详细信息

为了在玉米不同生长阶段进行气象要素影响评价和产量丰歉趋势定量评估,利用1983—2018年吉林省50个气象观测站4—9月逐日降水量、气温和风速等资料,以及各县逐年玉米产量资料,基于春玉米生长发育自然节律和模糊数学原理,将吉林省春玉米划分为5个生育阶段,构建基于诸阶段气象要素的理论—经验产量动态评估模型。该模型充分考虑各生育阶段内降水、气温、大风等关键气象要素对产量影响的比重、地域差异、气象要素综合影响及其阶段累加效应,可在每个生育阶段输出预期产量丰歉评估结果。拟合检验和试用显示模型输出结果客观性和实用性较好,评估模型在丰产年和歉收年的输出结果与实际产量拟合更好,后期评估结果比前、中期结果更贴近实际产量;中部半湿润半干旱区和东部冷湿山区的评估效果略好于西部半干旱地区的。

关键词：春玉米气象要素丰歉评估动态模型吉林省

QuEChERS结合GC-MS/MS检测果蔬中13种农药残留

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食品安全导刊 2024年第27期 63-67页

作者：管益涛陈明华谷翠梅马淑青潍坊市疾病预防控制中心山东潍坊261061

目的:基于QuEChERS方法结合气相色谱串联质谱(Gas Chromatography-Tandem mass Spectrometry,GC-MS/MS)技术,建立一种简单、快速检测果蔬中农药残留的方法。方法:果蔬样品匀浆后,先用乙腈和乙酸缓冲盐包提取,再用m-PFC小柱净化,最后用GC... 详细信息

目的:基于QuEChERS方法结合气相色谱串联质谱(Gas Chromatography-Tandem mass Spectrometry,GC-MS/MS)技术,建立一种简单、快速检测果蔬中农药残留的方法。方法:果蔬样品匀浆后,先用乙腈和乙酸缓冲盐包提取,再用m-PFC小柱净化,最后用GC-MS/MS测定,外标法定量。结果:13种农药在10~500μg·L^(-1)浓度范围内线性关系良好,相关系数(R^(2))均大于0.994,检出限为0.35~0.92μg·kg^(-1),定量限为1.0~2.8μg·kg^(-1);13种农药在3个水平下的加标回收率为82.4%~110.1%,相对标准偏差为2.9%~9.3%。结论:所建立的方法可操作性强,具有较高的精密度和准确度,可用于果蔬中农药残留的定性和定量检测。

关键词： QuEChERS 气相色谱串联质谱法农药残留果蔬

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High-resolution azimuth estimation algorithm based on data fusion method for the vector hydrophone vertical array

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Chinese Journal of Acoustics 2015年第3期34卷 312-324页

作者： CHEN Yu MENG Zhou ma shuqing BAO Changchun College of Optoelectric Science and Engineering National Univ.of Denfense Technology

To aim at the problem that the horizontal directivity index of the vector hy- drophone vertical array is not higher than that of a vector hydrophone, the high-resolution azimuth estimation algorithm based on the data fusion method was presented. The proposed algorithnl first employs MUSIC algorithm to estimate the azimuth of each divided sub-band signal, and then the estimated azimuths of multiple hydrophones are processed by using the data fusion technique. The high-resolution estimated result is achieved finally by adopting the weighted histogram statistics method. The results of the simulation and sea trials indicated that the proposed algorithm has better azimuth estimation performance than MUSIC algorithm of a single vector hydrophone and the data fusion technique based on the acoustic energy flux method. The better performance is reflected in the aspects of the estimation precision, the probability of correct estimation, the capability to distinguish multi-objects and the inhibition of the noise sub-bands.

关键词： MUSIC High-resolution azimuth estimation algorithm based on data fusion method for the vector hydrophone vertical array data

STRANGE ATTRACTORS ON PSEUDOSPECTRAL SOLUTIONS FOR DISSIPATIVE ZAKHAROV EQUATIONS1

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Acta mathematica Scientia 2004年第3期24卷 321-336页

作者： mashuqing ChangQianshun InstituteofAppliedmathematics theChineseAcademyofSciencesBeijing100080China

In this paper, the pseudospectral method to solve the dissipative Zakharov equations is used. Its convergence is proved by priori estimates. The existence of the global attractors and the estimates of dimension are presented. A class of steady state solutions is also disscussed. The numerical results show that if the steady state solutions satisfy some special conditions, they become unstable and limit cycles and strange attractors will occur for very small *** largest Lyapunov exponent and analysis of the linearized system are applied to explain these phenomena.

关键词： Strange attractors pseudospectral method Zakharov equations 65P20 76FXX

IAP's Solar-Powered Unmanned Surface Vehicle Actively Passes through the Center of typhoon Sinlaku(2020)

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Advances in Atmospheric Sciences 2021年第4期38卷 538-545页

作者： Hongbin CHEN Jun LI Wenying HE shuqing ma Yingzhi WEI Jidong PAN Yu ZHAO Xuefen ZHANG Shuzhen HU Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicChinese Academy of SciencesBeijing 100029China The School of Earth Science Chinese Academy of Science UniversityBeijing 100049China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Meteorological Observation Center of the China Meteorological Administration Beijing 100081China Xiamen Meteorological Service Xiamen 361013China

The solar-powered marine unmanned surface vehicle(USV) developed by the USV team of the Institute of Atmospheric Physics is a rugged, long-duration, and autonomous navigation vessel designed for the collection of longrange, continuous, real-time, meteorological and oceanographic measurements, especially under extreme sea conditions(sea state 6–7). These solar-powered USVs completed a long-term continuous navigation observation test over 26 *** this time, they coordinated double-USV observations and actively navigated into the path of Typhoon Sinlaku(2020) before collecting data very close to its center during the 2020 USV South China Sea Typhoon Observation Experiment. Detailed high temporal resolution(1 min) real-time observations collected by the USV on the typhoon were used for operational typhoon forecasting and warning for the first time. As a mobile meteorological and oceanographic observation station capable of reliable, automated deployment, data collection, and transmission, such solar-powered USVs can replace traditional observation platforms to provide valuable real-time data for research, forecasting, and early warnings for potential marine meteorological disasters.

关键词： solar-powered unmanned surface vehicle typhoon meteorological and oceanographic observation