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第一性原理计算研究V_(2)AlX(X=C、N)相的热力学性能

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热加工工艺 2024年第7期53卷 143-146页

作者：黄大建史沛然法涛表面物理与化学重点实验室四川绵阳621908

通过第一性原理基于PAW方法研究了V_(2)AlX(X=C、N)相的结构、电子、声子和热力学性质。讨论了V_(2)AlX(X=C、N)相的结构和电子特性;利用晶格动力学的超晶胞方法计算了声子色散曲线,并通过准简谐近似预测高温下V_(2)AlX(X=C、N)相的热... 详细信息

通过第一性原理基于PAW方法研究了V_(2)AlX(X=C、N)相的结构、电子、声子和热力学性质。讨论了V_(2)AlX(X=C、N)相的结构和电子特性;利用晶格动力学的超晶胞方法计算了声子色散曲线,并通过准简谐近似预测高温下V_(2)AlX(X=C、N)相的热力学性质。结果表明:V_(2)AlC和V_(2)AlN具有金属性,且用N原子置换C原子后费米面处的态密度减低。V_(2)AlC和V_(2)AlN都是动力学稳定的。此外,还发现V_(2)AlN相的热力学性质比V_(2)AlC的更优异,且V_(2)AlN的体模量也高于V_(2)AlC。

关键词： V_(2)AlX 电子声子热力学性能

Incidence and warning signs for complications of human brucellosis: a multi-center observational study from China

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Infectious Diseases of Poverty 2024年第1期13卷 53-62页

作者： Qing-Nan Shi Hui-Jie Qin Qiao-Shan Lu hu Li Zhong-fa tao Meng-Guang fan Mu-Heta Aishan Zeng-Qiang Kou Qiu-Lan Chen Wen-Wu Yin Yan-Ping Zhang National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases Chinese Center for Disease Control and PreventionChangbai RoadChangping DistrictBejing 102206China School of Public Health Guangxi Medical UniversityNanningChina Nanning Center for Disease Control and Prevention NanningChina Guizhou Center for Disease Control and Prevention GuiyangChina Inner Mongolia Center for Disease Control and Prevention HohhotChina Xinjiang Uighur Autonomous Region Center for Disease Control and Prevention UrumqiChina Shandong Center for Disease Control and Prevention JinanChina

Background Brucellosis is a severe zoonotic disease that is often overlooked, particularly in impoverished countries. Timely identification of focal complications in brucellosis is crucial for improving treatment outcomes. However, there is currently a lack of established indicators or biomarkers for diagnosing these complications. Therefore, this study aimed to investigate potential warning signs of focal complications in human brucellosis, with the goal of providing practical parameters for clinicians to aid in the diagnosis and management of *** A multi-center cross-sectional study was conducted in China from December 2019 to August 2021. The study aimed to investigate the clinical characteristics and complications of patients with brucellosis using a questionnaire survey and medical record system. The presence of warning signs for complications was assessed using univariate and multivariate logistic regression models. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used for variable screening and model *** A total of 880 participants diagnosed with human brucellosis were enrolled. The median age of the patients was 50 years [interquartile range (IQR): 41.5-58.0], and 54.8% had complications. The most common organ system affected by complications was the osteoarticular system (43.1%), with peripheral arthritis (30.0%), spondylitis (16.6%), paravertebral abscess (5.0%), and sacroiliitis (2.7%) being the most prevalent. Complications in other organ systems included the genitourinary system (4.7%), respiratory system (4.7%), and hematologic system (4.6%). Several factors were found to be associated with focal brucellosis. These factors included a long delay in diagnosis [odds ratio (OR) = 3.963, 95% confidence interval(CI): 1.906-8.238 for > 90 days], the presence of underlying disease (OR = 1.675, 95%CI: 1.176-2.384), arthralgia (OR = 3.197, 95%CI: 1.986-5.148), eye bulging pain (OR = 3.482, 95%CI:

关键词： Brucellosis Complications Clinical spectrum Warning signs

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基于深度强化学习的网联车辆队列纵向控制

控制与决策 2024年第6期39卷 1879-1887页

作者：李永福周发涛黄龙旺于树友施树明重庆邮电大学智能空地协同控制重庆市高校重点实验室重庆400065 吉林大学控制科学与工程系长春130012 吉林大学交通学院长春130012

针对车辆队列中多目标控制优化问题,研究基于强化学习的车辆队列控制方法.控制器输入为队列各车辆状态信息以及车辆间状态误差,输出为基于车辆纵向动力学的期望加速度,实现在V2X通信下的队列单车稳定行驶和队列稳定行驶.根据队列行驶场... 详细信息

针对车辆队列中多目标控制优化问题,研究基于强化学习的车辆队列控制方法.控制器输入为队列各车辆状态信息以及车辆间状态误差,输出为基于车辆纵向动力学的期望加速度,实现在V2X通信下的队列单车稳定行驶和队列稳定行驶.根据队列行驶场景以及采用的间距策略、通信拓扑结构等特性,建立队列马尔科夫决策过程(Markov decision process,MDP)模型.同时根据队列多输入-多输出高维样本特性,引入优先经验回放策略,提高算法收敛效率.为贴近实际车辆队列行驶工况,仿真基于PreScan构建多自由度燃油车动力学模型,联合Matlab/Simulink搭建仿真环境,同时引入噪声对队列控制器中动作网络和评价网络进行训练.仿真结果表明基于强化学习的车辆队列控制燃油消耗更低,且控制器实时性更高,对车辆的控制更为平滑.

关键词：车辆队列深度确定性策略梯度强化学习燃油消耗 V2X PreScan

LA-ICP-MSS多脉冲短时间剥蚀法锆石超薄增生边定年研究

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岩石矿物学杂志 2024年第4期43卷 1052-1065页

作者：陈静雅汪方跃王建周涛发李全忠合肥工业大学资源与环境工程学院合肥工业大学矿床成因与勘查技术研究中心(ODEC)安徽合肥230009 安徽省矿产资源与矿山环境工程技术研究中心安徽合肥230009 四川宝石花鑫盛油气运营服务有限公司四川成都610066

锆石是一种相对稳健的定年副矿物,其颗粒常常发育增生边,然而厚度极小(一般<5μm),给获得精确年龄带来挑战。本文从制样方法、实验条件及数据算法三个方面开展了实验对比研究,以评价多脉冲短时间剥蚀法对天然锆石的超薄增生边(~1μm)LA-... 详细信息

锆石是一种相对稳健的定年副矿物,其颗粒常常发育增生边,然而厚度极小(一般<5μm),给获得精确年龄带来挑战。本文从制样方法、实验条件及数据算法三个方面开展了实验对比研究,以评价多脉冲短时间剥蚀法对天然锆石的超薄增生边(~1μm)LA-ICP-MS U-Pb测年的可靠性。实验结果表明:双面胶制样虽然速度快,但是样品显微观察和后续激光分析的观察效果不佳;树脂固定制样效率高,易于透射光和反射光观察,并有利于样品表面聚焦。激光分析条件下,5 Hz、2 s剥蚀相对于10 Hz、1 s剥蚀数据结果更为稳定。数据处理峰积分法优于截距法和均值法。综合上述方法,获得Plesovice和Qinghu锆石^(206)Pb/^(238)U加权平均年龄与推荐值在误差范围内一致,但是数据误差相对较大(~5%,1σ)。根据每个信号峰峰值的50%~60%来选择信号区间,监控标样Plesovice和Qinghu准确值均提高了约3%。多脉冲短时间剥蚀法、树脂固定制样与部分峰积分数据处理方法组合可以获得较好的定年结果。本方法为测定锆石增生边年龄提供了一套完整的解决方案,可为多期次的地质过程提供更有效的年代学约束。

关键词：锆石增生边多脉冲短时间剥蚀法锆石制样方法峰面积积分法 U-Pb年代学

地基云雷达与FY-4A卫星云顶高度联合反演方法

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气象 2024年第7期50卷 859-867页

作者：张婷胡树贞陶法赵培涛刘文忠马婷印佳楠河北省气象技术装备中心石家庄050000 中国气象局气象探测中心北京100081

基于地基毫米波云雷达与FY-4A卫星对云顶同步观测的特点,分析云雷达垂直顶空观测的云顶高度与FY-4A卫星AGRI载荷通道数据之间关系,提出了地基云雷达与FY-4A卫星云顶高度联合反演方法,实现云雷达安装点周边区域卫星云顶高度的融合反演,... 详细信息

基于地基毫米波云雷达与FY-4A卫星对云顶同步观测的特点,分析云雷达垂直顶空观测的云顶高度与FY-4A卫星AGRI载荷通道数据之间关系,提出了地基云雷达与FY-4A卫星云顶高度联合反演方法,实现云雷达安装点周边区域卫星云顶高度的融合反演,并对反演结果进行验证分析。结果表明,AGRI载荷的第11~14通道值与云雷达观测云顶高度呈线性相关,且卫星通道值与云雷达观测云顶高度比值呈现冬季最小、春秋季次之、夏季最大的季节性变化特点;星地融合反演云顶高度与云雷达观测云顶高度相关系数0.84,融合后比融合前均方根误差减小了0.7 km,提高了卫星云顶高度的反演精度。

关键词：云云顶高度 FY-4A 毫米波云雷达数据融合

Dislocation and Elastic Strain in an InN Film Characterized by Synchrotron Radiation X-Ray Diffraction and Rutherford Backscattering/Channeling

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Chinese Physics Letters 2012年第2期29卷 148-151页

作者： CHENG Feng-Feng fa tao WANG Xin-Qiang YAO Shu-De State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871 State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871

Dislocation information and strain-related tetragonal distortion as well as crystalline qualities of a 2-μm-thick InN film grown by molecular beam epitaxy (MBE) are characterized by Rutherford backscattering/channeling (RBS/C) and synchrotron radiation x-ray diffraction (SR-XRD).The minimum yield xmin=2.5% deduced from the RBS/C results indicates a fairly good crystalline *** the SR-XRD results,we obtain the values of the screw and edge densities to be ρscrew =7.0027 X 10^(9) and ρedge =8.6115 × 10^(9) cm-2,*** tetragonal distortion of the sample is found to be -0.27 % by angular scans,which is close to the -0.28 % derived by *** value of |e(⊥)/e‖| =0.6742 implies that the InN layer is much stiffer along the a axis than that along the c axis,where e‖ is the parallel elastic strain,and e⊥ is the perpendicular elastic *** results reveal a main peak of 0.653eV with the linewidth of 60meV,additional shoulder band could be due to impurities and related defects.

关键词： distortion crystalline Rutherford

Automatic Identification of Clear-Air Echoes Based on Millimeter-wave Cloud Radar Measurements

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Advances in Atmospheric Sciences 2020年第8期37卷 912-924页

作者： Ling YANG Yun WANG Zhongke WANG Qian YANG Xingang faN fa tao Xiaoqiong ZHEN Zhipeng YANG Electronic Engineering College Chengdu University of Information TechnologyChengdu 610225China Information Security Engineering College Chengdu University of Information TechnologyChengdu 610225China Department of Geography and Geology Western Kentucky UniversityBowling GreenKY 42101USA Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China CMA Key Laboratory of Atmospheric Sounding Chengdu University of Information TechnologyChengdu 610225China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing210044China Meteorological Observation Centre CMABeijing 100081China

Millimeter-wave cloud radar(MMCR)provides the capability of detecting the features of micro particles inside clouds and describing the internal microphysical structure of the ***,MMCR has been widely applied in cloud ***,due to the influence of non-meteorological factors such as insects,the cloud observations are often contaminated by non-meteorological echoes in the clear air,known as clear-air *** is of great significance to automatically identify the clear-air echoes in order to extract effective meteorological information from the complex weather *** characteristics of clear-air echoes are studied here by combining data from four devices:an MMCR,a laser-ceilometer,an L-band radiosonde,and an all-sky *** addition,a new algorithm,which includes feature extraction,feature selection,and classification,is proposed to achieve the automatic identification of clear-air *** results show that the recognition algorithm is fairly satisfied in both simple and complex weather *** recognition accuracy can reach up to 95.86%for the simple cases when cloud echoes and clear-air echoes are separate,and 88.38%for the complicated cases when low cloud echoes and clear-air echoes are mixed.

关键词： millimeter-wave cloud radar clear-air echoes neural network laser ceilometer all-sky camera feature extraction feature selection

Congenital nephrogenic diabetes insipidus due to the mutation in AVPR2(c.541C>T)in a neonate:A case report

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World Journal of Clinical Cases 2020年第24期8卷 6418-6424页

作者： fa-tao Lin Jing Li Bang-Li Xu Xiu-Xiu Yang fang Wang Department of Neonatology Children’s Hospital Affiliated to Zhengzhou UniversityHenan Children’s HospitalZhengzhou Children’s HospitalZhengzhou 450000Henan ProvinceChina Department of Infectious Diseases Children’s Hospital Affiliated to Zhengzhou UniversityHenan Children’s HospitalZhengzhou Children’s HospitalZhengzhou 450000Henan ProvinceChina

BACKGROUND Congenital nephrogenic diabetes insipidus (CNDI) is a rare hereditary renaldisorder that is caused by mutations in AVPR2 or aquaporin 2 (AQP2). Up tonow, there are few reports about CNDI in neonates. Early clinical manifestationsof CNDI in neonates are atypical. A lack of understanding of the disease byclinicians causes frequent misdiagnoses or missed diagnoses, which may result infailure to administer treatments in time and ultimately leads to severecomplications. In this study, clinical data of a case of AVPR2 gene mutationinducedCNDI, which was confirmed by genetic testing, were retrospectivelyanalyzed to improve our understanding of this *** SUMMARY On February 1, 2020, a male neonate was hospitalized 17 d after birth due to a 7 dperiod of pyrexia. The patient’s symptoms included recurrent pyrexia,hypernatremia and hyperchloremia, which were difficult to treat. The patient wasfed on demand, and water was additionally provided between milk intakes. Acombination treatment of hydrochlorothiazide and amiloride was *** the treatment, body temperature and electrolyte levels returned to normal,the volume of urine was significantly reduced and the patient was subsequentlydischarged. Genetic tests confirmed that the patient carried the AVPR2 genemissense mutation c.541C>T (P.R181C), and the patient’s mother carried aheterozygous mutation at the same locus. After clinical treatment with acombination of hydrochlorothiazide and amiloride, the body temperature andelectrolyte levels returned to normal. Up until the most recent follow-up examination, normal body temperature, electrolyte levels and growth anddevelopment were *** CNDI in the neonatal period is rare, and its clinical manifestations are unspecificwith some patients merely showing recurrent fever and electrolyte *** testing of AVPR2 and AQP2 can be used for screening and geneticdiagnosis of CNDI.

关键词： Neonate Congenital nephrogenic diabetes insipidus AVPR2 gene Gene mutation Magnetic resonance imaging Case report

Intelligent casting:Empowering the future foundry industry

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China Foundry 2024年第5期21卷 409-426页

作者： Jin-wu Kang Bao-lin Liu tao Jing Hou-fa Shen School of Materials Science and Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua UniversityBeijing 100084China

Emerging technological advances are reshaping the casting sector in latest *** technology is evolving towards intelligent casting paradigm that involves automation,greenization and intelligentization,which attracts more and more attention from the academic and industry *** this paper,the main features of casting technology were briefly summarized and forecasted,and the recent developments of key technologies and the innovative efforts made in promoting intelligent casting process were ***,the technical visions of intelligent casting process were also put *** key technologies for intelligent casting process comprise 3D printing technologies,intelligent mold technologies and intelligent process control *** future,the intelligent mold that derived from mold with sensors,control devices and actuators will probably incorporate the Internet of Things,online inspection,embedded simulation,decision-making and control system,and other technologies to form intelligent cyber-physical casting system,which may pave the way to realize intelligent *** is promising that the intelligent casting process will eventually achieve the goal of real-time process optimization and full-scale control,with the defects,microstructure,performance,and service life of the fabricated castings can be accurately predicted and tailored.

关键词： intelligent casting 3D printing intelligent mold process control cyber-physical casting system embedded simulation