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Advances in Atmospheric Sciences 2018年第6期35卷 713-722页

作者： Shuixin zhong Zitong CHEN Daosheng XU Yanxia ZHANG Guangdong Province Key Laboratory of Regional Numerical Weather Prediction Institute of Tropical and Marine MeteorologyChina Meteorological Administration

Unresolved small-scale orographic（SSO） drags are parameterized in a regional model based on the Global/Regional Assimilation and Prediction System for the Tropical Mesoscale Model（GRAPES TMM）. The SSO drags are represented by adding a sink term in the momentum equations. The maximum height of the mountain within the grid box is adopted in the SSO parameterization（SSOP） scheme as compensation for the drag. The effects of the unresolved topography are parameterized as the feedbacks to the momentum tendencies on the first model level in planetary boundary layer（PBL）parameterization. The SSOP scheme has been implemented and coupled with the PBL parameterization scheme within the model physics package. A monthly simulation is designed to examine the performance of the SSOP scheme over the complex terrain areas located in the southwest of Guangdong. The verification results show that the surface wind speed bias has been much alleviated by adopting the SSOP scheme, in addition to reduction of the wind bias in the lower troposphere. The target verification over xinyi shows that the simulations with the SSOP scheme provide improved wind estimation over the complex regions in the southwest of Guangdong.

关键词： small-scale orographic drag GRAPES_TMM PBL parameterization wind bias

基于Facet模型及组合式假人对汽车-摩托车碰撞事故的仿真

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振动与冲击 2018年第14期37卷 44-50页

作者：孔令爽秦闯金先龙侯心一邱忠上海交通大学机械动力与工程学院上海200240 上海市公安局交通警察总队上海200070

为了更好的解决汽车-摩托车碰撞事故的仿真再现问题,一种新的仿真模型及方法被提出。该方法采用Facet模型建立事故汽车及摩托车的三维模型,采用组合式假人模型建立骑车人的三维模型。由Photomodeler软件得出碰撞初始条件,并利用Madymo... 详细信息

为了更好的解决汽车-摩托车碰撞事故的仿真再现问题,一种新的仿真模型及方法被提出。该方法采用Facet模型建立事故汽车及摩托车的三维模型,采用组合式假人模型建立骑车人的三维模型。由Photomodeler软件得出碰撞初始条件,并利用Madymo软件对事故碰撞过程进行直观的三维仿真再现。针对一起实际的轿车与摩托车碰撞事故,采用上述仿真模型及方法进行事故模拟。仿真结果与实际事故情况可以较好吻合,人体损伤数据与法医鉴定结果可以较好吻合,从而验证了此种仿真模型及方法的可行性及有效性。

关键词： Facet模型组合式假人 Madymo 碰撞仿真

组合式假人建模在两轮电动车交通事故模拟中的应用

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上海交通大学学报 2019年第4期53卷 447-453页

作者：秦闯傅双枝金先龙侯心一邱忠上海交通大学机械与动力工程学院上海200240 上海市公安局交通警察总队上海200070

通过对标准多刚体假人和有限元人体模型进行拆分、组合、缩放,建立基于受害人真实体型特征参数的多刚体-有限元组合式假人模型,应用于一起真实两轮电动车交通事故的模拟.采用摄影测量法计算车辆碰撞速度,对事故发生时刻的现场进行三维重... 详细信息

通过对标准多刚体假人和有限元人体模型进行拆分、组合、缩放,建立基于受害人真实体型特征参数的多刚体-有限元组合式假人模型,应用于一起真实两轮电动车交通事故的模拟.采用摄影测量法计算车辆碰撞速度,对事故发生时刻的现场进行三维重构,分析了碰撞后人和车的动力学响应以及电动车骑车人的损伤情况.碰撞后人和车的运动形态与真实情况基本吻合,通过模拟计算得到假人头部损伤准则(HIC)值、小腿最大弯矩和颅骨von Mises应力云图,人体损伤判定和法医鉴定结果一致,有效验证了组合式假人模型用于交通事故模拟的正确性和准确性.

关键词：组合式假人两轮电动车骑车人事故模拟人体损伤

基于改进LSTM网络的无人机MEMS-IMU零偏在线标定方法

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中国惯性技术学报 2024年第3期32卷 213-218页

作者：程向红吴昕怡刘丰宇钟志伟微惯性仪表与先进导航技术教育部重点实验室南京210096 东南大学仪器科学与工程学院南京210096

针对在卫星信号拒止、视觉系统退化场景中无人机MEMS-IMU零偏无法准确估计并补偿导致导航误差迅速发散的问题,提出一种基于改进长短时记忆(LSTM)网络的零偏在线标定方法。首先,为解决MEMS-IMU零偏数据非线性强、传统循环时间网络训练效... 详细信息

针对在卫星信号拒止、视觉系统退化场景中无人机MEMS-IMU零偏无法准确估计并补偿导致导航误差迅速发散的问题,提出一种基于改进长短时记忆(LSTM)网络的零偏在线标定方法。首先,为解决MEMS-IMU零偏数据非线性强、传统循环时间网络训练效果差的问题,设计序列到序列的LSTM神经网络结构,引入教师强迫机制,提高了网络特征学习能力。然后,在导航过程中使用训练后的网络对MEMS-IMU零偏在线标定,补偿后的IMU量测与视觉信息联合优化,保证了导航定位精度。实验结果表明,在纯惯性导航实验中,所提方法的绝对位置误差比传统LSTM方法减小了6.5%;在EUROC数据集下进行的视觉惯性组合导航实验中,所提方法的平均绝对位置误差比传统LSTM方法减小了15%。

关键词：无人机导航定位微惯性测量单元在线标定长短时记忆神经网络

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奶牛卧床冷水管局部降温系统应用效果分析

农业工程学报 2021年第15期37卷 197-203页

作者：杜欣怡仲玉婷施正香桂锦明中国农业大学水利与土木工程学院北京100083 农业农村部设施农业工程重点实验室北京100083

为缓解奶牛热应激,该研究基于奶牛胸颈部热敏感区产热及散热理论,开发了一套卧床冷水管局部降温系统。该研究在自然通风牛舍,通过水管壁温与试验组卧床表面温度变化测试了系统性能,并通过试验组与对照组奶牛核心体温、呼吸频率、产奶量... 详细信息

为缓解奶牛热应激,该研究基于奶牛胸颈部热敏感区产热及散热理论,开发了一套卧床冷水管局部降温系统。该研究在自然通风牛舍,通过水管壁温与试验组卧床表面温度变化测试了系统性能,并通过试验组与对照组奶牛核心体温、呼吸频率、产奶量及躺卧行为的差异分析了系统的应用效果。试验期间,系统水管壁温的变化范围为18~22℃,进出水温差1.7℃;试验组卧床表面平均温度维持在21~23℃,比对照组显著降低2.1℃(P<0.01)。结果表明,卧床冷水管局部降温系统水管壁温与距进水口的管道长度呈线性正相关关系。当温湿指数(Temperature-Humidity Index,THI)达到72时,试验组奶牛核心体温比对照组降低0.3℃(P<0.01),呼吸频率降低9次/min(P<0.01),证明卧床冷水管局部降温系统可有效缓解奶牛热应激。该研究为牛舍环境局部降温及缓解奶牛热应激提供了方法支撑。

关键词：温度动物奶牛热应激水冷式卧床局部降温

Integrative analyses reveals the transcriptome-proteome correlation in biological pathways and secondary metabolism clusters in A. flavus in response to temperature

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Integrative analyses reveals the transcriptome-proteome corr...

中国菌物学会2015年学术年会

作者： Youhuang Bai Sen Wang Hong zhong Qi Yang Feng Zhang Zhenhong Zhuang Jun Yuan xinyi Nie Shihua Wang Key Laboratory of Pathogenic Fungi and Mycotoxins of Fujian Province and School of Life SciencesFujian Agriculture and Forestry University

One of major determinant of aflatoxin production in Aspergillus. flavus is temperature1,2, which is favorable for growth but disadvantage for aflatoxin production at 37°C, and the opposite at 28°C. Two fundamental strategies, termed "bottom-up" and "top-down" approaches, were used to identify proteins and quantify the changes on proteome level of A. flavus in response to temperature changes4,5,6,7. But very little information is available on the changes on transcriptome-proteome level of A. flavus in response to temperature changes. To investigate the changes in transcript and relative protein level in response to temperature, complementary transcriptomic and proteomic analyses were used to identify changes in A. flavus grow at 28°C and 37°C. A total of 3,886 proteins were identified, and 2,832 were reliably quantified. A subset of 664 proteins was differentially expressed upon temperature changes and enriched on several KEGG pathways: translation-related pathways, metabolic pathways and biosynthesis of secondary metabolites. The changes in protein profiles showed low congruency with alterations in corresponding transcript levels, indicating post-transcriptional processes play critical role on regulation of the protein level in A. flavus. The expression pattern of proteins and transcripts related to aflatoxin biosynthesis showed that most genes were up-regulated at both proteins and transcripts level at 28°C. Our data provide the comprehensive quantitative proteome data of A. flavus at conducive and non- conducive temperatures.

关键词： Aspergillus flavus Aflatoxin Proteome Transcriptome Temperature

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面向无人机通信的区域化智能波束管理

无线电通信技术 2024年第3期50卷 503-509页

作者：赵乐郑重王新奕费泽松北京理工大学信息与电子学院北京100081

面向新一代无线通信的技术革新,无人机(Unmanned Aerial Vehicle,UAV)在未来通信系统中的应用越来越不可忽视。考虑传统波束管理(Beam Management,BM)方法在高动态、高频段空地链路中波束对准的高额开销,设计了一种基于人工智能(Artific... 详细信息

面向新一代无线通信的技术革新,无人机(Unmanned Aerial Vehicle,UAV)在未来通信系统中的应用越来越不可忽视。考虑传统波束管理(Beam Management,BM)方法在高动态、高频段空地链路中波束对准的高额开销,设计了一种基于人工智能(Artificial Intelligence,AI)技术的BM方案。方案基于长短时记忆(Long-Short Term Memory,LSTM)网络模型,利用深度学习(Deep Learning,DL)方法实现基站(Base Station,BS)-UAV通信过程中的BM。以参考信号接收功率(Reference Signal Receive Power,RSRP)为性能指标对BM方案进行评估,基于BM历史经验数据将UAV终端轨迹划分为数个区域,训练特定的区域模型以更好地适应各区域中的信道传播环境特征。在模型部署阶段,根据区域划分结果按区域切换模型,实现基于模型切换的区域化AI-BM(Model Switching based Area-Specific AI-BM,MSAS AI-BM)。仿真结果表明,所提的MSAS AI-BM方案相比传统的简单穷举BM方案能够极大降低系统开销,拥有良好的RSRP保持性能。

关键词：波束管理人工智能参考信号接收功率长短时记忆模型切换

The Influential Mechanisms of Theory of Mind on Prosocial Behavior and the Effect of Mindfulness Intervention

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International Journal of Mental Health Promotion 2024年第9期26卷 679-695页

作者： Sisi Li Nailiang zhong Qingke Guo Department of Psychology Guangxi Normal UniversityGuilin541006China School of Teacher Education Hechi UniversityHechi546300China South China Normal University Liru Senior High School Xinyi525300China

Background:Theory of Mind(ToM)and empathy are crucial cognitive and emotional capacities that influence social *** their role in promoting prosocial behavior has been established,the potential moderating effect of mindfulness on this relationship remains *** these complex interactions is vital for developing effective interventions to foster prosocial behavior among college *** study examines the influence of ToM on college students’prosocial behavior and explores the moderating role of mindfulness in this ***:A mixed-methods approach combining questionnaires and experimental design was *** 1:A survey of 759 college students(mean age 22.03 years;477 females)was conducted using the ToM Scale,Interpersonal Reactivity Index,Prosocial Behavior Tendency Scale,and Mindfulness Awareness *** were analyzed using correlation and moderated mediation *** 2:An 8-week mindfulness attention training program was implemented for the intervention group and compared with a control *** training served as a moderating variable to validate Model 59 from Study ***:*** 1 found:(a)ToM was significantly positively correlated with prosocial behavior(r=0.31,p<0.01).(b)Empathy partially mediated the relationship between ToM and prosocial behavior(β=0.10,p<0.001,95%CI[0.06,0.14]).(c)Mindfulness negatively moderated the direct path between ToM and three dimensions of prosocial behavior,as well as the indirect path between empathy and kin altruism and reciprocal ***,high levels of mindfulness weakened the direct impact of ToM on prosocial *** levels of mindfulness also weakened the indirect influence of ToM on prosocial behavior through *** 2 results showed:(a)The intervention group had significantly higher levels of trait mindfulness compared to the control group(t=2.56,p<0.05).(b)The validity of the moderated mediation model 59 from Study 1 w

关键词： Prosocial behavior Theory of Mind trait mindfulness empathy mindfulness intervention

采用小孔等离子体开关实现TE CO_2激光窄脉冲整形

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红外与激光工程 2018年第12期47卷 44-47页

作者：柯常军吴天昊孔心怡钟艳红吴谨中国科学院电子学研究所北京100190 中国科学院大学北京100049

典型的TE CO_2激光脉冲,通常由高功率窄脉冲(100 ns)和低功率长拖尾部分(3～5μs)组成。采用一种简单的小孔等离子体开关技术可以实现对低功率长拖尾部分的有效吸收和散射,保留需要的高功率窄脉冲前沿部分,达到激光脉冲压缩和整形目的... 详细信息

典型的TE CO_2激光脉冲,通常由高功率窄脉冲(100 ns)和低功率长拖尾部分(3～5μs)组成。采用一种简单的小孔等离子体开关技术可以实现对低功率长拖尾部分的有效吸收和散射,保留需要的高功率窄脉冲前沿部分,达到激光脉冲压缩和整形目的。详细研究了小孔位于不同离焦距离时整形激光脉冲波形的变化,获得了整形激光脉宽、能量与离焦距离的变化关系,实现了50～110 ns的窄脉冲CO_2激光输出。进一步研究发现,小孔等离子体开关的使用寿命主要由激光脉冲能量、重复频率、整形脉冲宽度决定。通过该技术实现的窄脉冲CO_2激光可以用于极紫外光刻等离子体光源、激光雷达等领域的研究。

关键词：激光脉冲整形 TE CO2激光小孔等离子体开关

EVALUATION OF THE PARAMETERIZATION SCHEMES AND NUDGING TECHNIQUES IN GRAPES FOR WARM SECTOR TORRENTIAL RAINS USING SURFACE OBSERVATIONS

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Journal of Tropical Meteorology 2019年第3期25卷 353-364页

作者： zhong Shui-xin YANG Shuai CHEN Zi-tong Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction Institute of Tropical and Marine MeteorologyCMAGuangzhou 510080 China Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 China

Sensitivities of parameterization schemes were conducted based on the Global/Regional Assimilation and Prediction System(GRAPES) model. Surface observations were used to evaluate the simulations and to improve the model’s ability to simulate the extreme precipitation over southern China on 20 July 2016. The results showed that GRAPES captured the large-scale precipitation over southern China but failed to predict the extreme precipitation over xinyi. The model showed a systematic cold biases by adopting different parameterization schemes. In particular, the ECMWF analyses data showed a strong cold bias over Guangdong province and Guangxi region. Observational nudging results showed that the surface temperature could largely help to alleviate the cold bias. The alleviation in the warm sector accounted for main improvement by the nudging scheme, and the RMSE was reduced by 1.56 degree from 3.25 degree to 1.69 degree by 1-h simulation and with 1.3 degree alleviation by 2-h simulation. Sensitivities using different parameterizations and the nudging scheme showed that the model’s underestimation of the precipitation was still present despite improvements in the predictions of surface temperature.

关键词： GRAPES extreme precipitation warm sector cold bias observational nudging