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基于混合简化粒子群算法的贝叶斯网络结构学习研究

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计量学报 2024年第2期45卷 269-278页

作者：刘浩然李晟崔少鹏王念太蔡炎滨时倩蕊张力悦燕山大学信息科学与工程学院河北秦皇岛066004 河北省特种光纤与光纤传感重点实验室河北秦皇岛066004

为改善当前贝叶斯网络结构学习算法易陷入局部最优、过早收敛和寻优效率低的问题,进行了混合简化粒子群算法优化贝叶斯网络结构学习的研究。该算法利用最大支撑树约束搜索空间,并提出V-结构与条件相对平均熵相结合的初始定向策略,然后... 详细信息

为改善当前贝叶斯网络结构学习算法易陷入局部最优、过早收敛和寻优效率低的问题,进行了混合简化粒子群算法优化贝叶斯网络结构学习的研究。该算法利用最大支撑树约束搜索空间,并提出V-结构与条件相对平均熵相结合的初始定向策略,然后利用爬山策略建立初始粒子群,再利用改进的粒子群优化算法和遗传算法对初始种群迭代优化,在迭代过程中提出条件交叉和变异策略避免粒子的随机发散更新,并结合副粒子增缓策略更新未优化粒子,避免算法陷入局部最优。该算法与其他算法在4种标准网络下进行了仿真实验。实验结果表明,所提算法在ASIA、CAR、CHILD、ALARM网络中相比于MMHC、GS、BNC-PSO、PC-PSO算法BIC评分分别平均高5.775%、5.8%、0.475%、2.75%;汉明距离HD更低,正确率ACC更高。

关键词：智能算法贝叶斯网络粒子群优化遗传算法自定义交叉和变异概率副粒子增缓策略

Standardization of tritiated water by the CIEMAT/NIST and TDCR methods

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Science China(Technological Sciences) 2015年第3期58卷 559-564页

作者： WU YongLe liu haoran LIANG JunCheng liu JiaCheng XIONG WenJun YUE HuiGuo liu SenLin YANG YuanDi YUAN DaQing China Institute of Atomic Energy Nuclear and Radiation Safety Center National Institute of Metrology

The activity of tritiated water has been standardized by two liquid scintillation counting methods:The CIEMAT/NIST method with the54Mn-standard efficiency tracing and the triple-to-double coincidence ratio(TDCR)*** samples were prepared with Ultima Gold TM AB liquid scintillation cocktail in low-potassium glass *** the application of the CIEMAT/NIST method,the computer program EMILIA was used to calculate the efficiency of3H and54Mn according to the KL1L2L3M atomic rearrangement *** the detection efficiency of the TDCR counter was calculated using TDCR07 code,which makes it possible to allow for the potential asymmetry between the three photomultiplier *** influence of stopping power and k B factor is discussed in the *** a power approach is adopted for the stopping power for electrons below 1ke V and k B is chosen to be 0.0075 cm/Me V,the relative deviation will be only 0.3%between the two methods.

关键词： tritiated water the CIEMAT/NIST method the TDCR method k B factor the stopping power liquid scintillation counting

Synthesis and Acetylcholinesterase Inhibitory Activity of Polymethoxyflavone Mannich Base Derivatives

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Chemical Research in Chinese Universities 2017年第4期33卷 594-597页

作者： SHI Ling ZHANG Yanhua WANG Caifang liu haoran WANG Qiuan College of Chemistry and Chemical Engineering Hunan University Changsha 410082 P. R. China

A series of novel polymethoxyflavone Marmich base derivatives 1--8 was synthesized by Mannich reaction of 5-hydroxy-3,7,3＇,4＇-tetramethoxyflavone 9 with various secondary aliphatic amines and formaldehyde. Their acetylcholmesterase（AChE） inhibitory activities were evaluated. The results showed that most of them exhibited AChE inhibitory activity and especially piperidin-l-yl methyl substituent derivative 5（IC50=0.238 μmol/L） demon- strated stronger activity comparable with the positive control, neoeserinemethyl sulfate（IC50=1.39 μmol/L）, which is worthy of further development as an agent for Alzheimer＇s disease treatment.

关键词： Polymethoxyflavone Mannich base derivative Acetylcholinesterase inhibitory activity

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高校流行病学课程思政现状及实施途径

继续医学教育 2024年第2期38卷 113-116页

作者：董雨晴刘浩然王萍玉滨州医学院公共卫生与管理学院山东烟台264003

流行病学作为公共卫生专业一门重要的专业课程,不仅包含专业知识,也包含丰富的科学精神、人文精神,蕴藏了极为丰富的思政资源。在培养公共卫生领域人才过程中,课程思政具有重要意义。文章聚焦于流行病学课程思政的教学现状,针对流行病... 详细信息

流行病学作为公共卫生专业一门重要的专业课程,不仅包含专业知识,也包含丰富的科学精神、人文精神,蕴藏了极为丰富的思政资源。在培养公共卫生领域人才过程中,课程思政具有重要意义。文章聚焦于流行病学课程思政的教学现状,针对流行病学专业课中可能存在的教师缺乏思政教学意识、思政内容融入生硬、授课时间有限这些问题进行分析,从强化高校流行病学教师思政教学意识、挖掘流行病学思政元素、健全流行病学课程思政体系三个方面提出流行病学课程思政的实施途径。文章突破传统的流行病学专业课教学方式,在专业课中融入课程思政内容,并将思想政治教育贯穿教育教学全过程。文章进一步提炼流行病学课程中潜在的思政价值,充分发挥流行病学课程的德育功能,将其转化为社会主义核心价值观的有效教学载体,引导医学生成长为符合时代发展要求的德才兼备的公共卫生领域人才。

关键词：流行病学课程思政公共卫生医学生实施途径人才培养

Optical manipulation of the topological phase in ZrTe_(5) revealed by time-and angle-resolved photoemission

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Chinese Physics B 2024年第1期33卷 170-175页

作者：黄超之徐骋洋朱锋锋段绍峰刘见喆顾凌霄王石崇刘浩然钱冬罗卫东张文涛 Key Laboratory of Artificial Structures and Quantum Control School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

High-resolution time-and angle-resolved photoemission measurements were conducted on the topological insulator ZrTe_(5).With strong femtosecond photoexcitation,a possible ultrafast phase transition from a weak to a strong topological insulating phase was experimentally realized by recovering the energy gap inversion in a time scale that was shorter than 0.15 *** photoinduced transient strong topological phase can last longer than 2 ps at the highest excitation fluence studied,and it cannot be attributed to the photoinduced heating of electrons or modification of the conduction band ***,the measured unoccupied electronic states are consistent with the first-principles calculation based on experimental crystal lattice constants,which favor a strong topological insulating *** findings provide new insights into the longstanding controversy about the strong and weak topological properties in ZrTe_(5),and they suggest that many-body effects including electron–electron interactions must be taken into account to understand the equilibrium weak topological insulating phase in ZrTe_(5).

关键词： time-and angle-resolved photoemission spectroscopy electronic structure topological insulator

Vertical distribution and temporal evolution of formaldehyde and glyoxal derived from MAX-DOAS observations:The indicative role of VOC sources

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Journal of Environmental Sciences 2022年第12期34卷 92-104页

作者： Qianqian Hong Cheng liu Qihou Hu Yanli Zhang Chengzhi Xing Jinping Ou Wei Tan haoran liu Xiaoqing Huang Zhenfeng Wu School of Environment and Civil Engineering Jiangnan UniversityWuxi 214122China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Environmental Optics&Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China Anhui Province Key Laboratory of Polar Environment and Global Change University of Science and Technology of ChinaHefei 230026China Guangdong Key Laboratory of Environmental Protection and Resources Utilization State Key Laboratory of Organic GeochemistryGuangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou 510632China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China

Formaldehyde(HCHO)and glyoxal(CHOCHO)are important oxidization intermediates of most volatile organic compounds(VOCs),but their vertical evolution in urban areas is not well *** profiles of HCHO,CHOCHO,and nitrogen dioxide(NO_(2))were retrieved from ground-based Multi-Axis Differential Optical Absorption Spectroscopy(MAXDOAS)observations in Hefei,*** and CHOCHO vertical profiles prefer to occur at higher altitudes compared to NO_(2),which might be caused by the photochemistry-oxidation of longer-lived VOCs at higher *** means of HCHO concentrations were higher in summer,while enhanced amounts of NO_(2)were mainly observed in *** exhibited a hump-like seasonal variation,with higher monthly-averaged values not only occurred in warm months(July-August)but also in cold months(November-December).Peak values mainly occurred during noon for HCHO but emerged in the morning for CHOCHO and NO_(2),suggesting that HCHO is stronger link to photochemistry than *** further use the glyoxal to formaldehyde ratio(GFR)to investigate the VOC sources at different *** lowest GFR value is almost found in the altitude from 0.2 to 0.4 km,and then rises rapidly as the altitude *** GFR results indicate that the largest contributor of the precursor VOC is biogenic VOCs at lower altitudes,while at higher altitudes is anthropogenic *** findings provide a lot more insight into VOC sources at vertical direction,but more verification is recommended to be done in the future.

关键词： Formaldehyde Glyoxal MAX-DOAS Vertical distribution VOC

First observation of tropospheric nitrogen dioxide from the Environmental Trace Gases Monitoring Instrument onboard the GaoFen-5 satellite

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Light(Science & Applications) 2020年第1期9卷 1389-1397页

作者： Chengxin Zhang Cheng liu Ka Lok Chan Qihou Hu haoran liu Bo Li Chengzhi Xing Wei Tan Haijin Zhou Fuqi Si Jianguo liu School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China Remote Sensing Technology Institute(IMF) German Aerospace Center(DLR)OberpfaffenhofenGermany

The Environmental Trace Gases Monitoring Instrument(EMI)is the first Chinese satellite-borne UV–Vis spectrometer aiming to measure the distribution of atmospheric trace gases on a global *** EMI instrument onboard the GaoFen-5 satellite was launched on 9 May *** this paper,we present the tropospheric nitrogen dioxide(NO2)vertical column density(VCD)retrieval algorithm dedicated to EMI *** report the first successful retrieval of tropospheric NO_(2) VCD from the EMI *** retrieval improved the original EMI NO_(2) prototype algorithm by modifying the settings of the spectral fit and air mass factor calculations to account for the on-orbit instrumental performance *** retrieved EMI NO_(2) VCDs generally show good spatiotemporal agreement with the satellite-borne Ozone Monitoring Instrument and TROPOspheric Monitoring Instrument(correlation coefficient R of ~0.9,bias<50%).A comparison with ground-based MAX-DOAS(Multi-Axis Differential Optical Absorption Spectroscopy)observations also shows good correlation with an R of *** results indicate that the EMI NO_(2) retrieval algorithm derives reliable and precise results,and this algorithm can feasibly produce stable operational products that can contribute to global air pollution monitoring.

关键词： measurement dioxide satellite

A flexible conductive hybrid elastomer for high-precision stress/strain and humidity detection

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Journal of Materials Science & Technology 2019年第1期35卷 176-180页

作者： haoran liu Zhenyi Zhang Jun Ge Xiao Lin Xinye Ni Huilin Yang Lei Yang Orthopaedic Institute Department of Orthopaedics Soochow University Division of Environmental Technology INET Tsinghua University Second People’s Hospital of Changzhou Nanjing Medical University International Research Center for Translational Orthopaedics (IRCTO) Soochow University

Flexible and environment-responsive materials are essential for a large number of applications from artificial skin to wearable devices. The present study develops a flexible, ultra-low cost conductive hybrid elastomer(CHE), which possesses high responsive capabilities to stress/strain and humidity. CHE was composed of polydimethylsiloxane(PDMS) and starch hydrogel(SH), enabling great elasticity(56 kPa),high conductivity(10^(-2)S/m) and high sensitivity to external stimuli(gauge factor of CHE under stress and strain are 0.71 and 2.22, respectively, and sensitivity to humidity is 1.2 × 10^(-6)S/m per RH%). These properties render CHE a promising candidate for artificial skin and wearable electronics applications of continuously monitoring environmental information.

关键词： Conductive composites Electrical properties Mechanical properties Moisture Hybrid Elastomer

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古代医家对疫病致病因素的类述

中医临床研究 2024年第12期16卷 33-37页

作者：陈谦峰刘浩然吉瑞蔡华珠江西中医药大学江西南昌330004 福建中医药大学福建福州350122

疫病在给人类造成严重负面影响的同时,也促进了医学的发展。纵观中医发展史,从《黄帝内经》的“百病生于气”“三年化疫”,到《伤寒杂病论》对寒疫的详实记载,再到《温疫论》的“杂气”致疫,各时代对疫病致病因素的认识在逐步加深。几... 详细信息

疫病在给人类造成严重负面影响的同时,也促进了医学的发展。纵观中医发展史,从《黄帝内经》的“百病生于气”“三年化疫”,到《伤寒杂病论》对寒疫的详实记载,再到《温疫论》的“杂气”致疫,各时代对疫病致病因素的认识在逐步加深。几千年来,中医在疫病的防治实践中积累了丰富的经验,形成成熟理论,留下的大量著作,是世界其他任何民族无法相比的。基于此,文章探讨了古代医家对疫病致病因素的理解和认识,首先,阐述疫病的概念和特征,并引用了多个历史文献中的记载来证明疫病具有强烈的传染性和流行性。其次,阐述古代医家关于疫病致病因素的六种观点:六气致疫、伏气致疫、杂气致疫、毒气致疫、虫邪致疫、温邪致疫。在六气致疫中,古代医家详细讨论了寒、火、燥、湿四种致病因素的作用机制。对于伏气致疫的观点,列举了几种不同的病邪伏藏在人体内的位置和发作条件,如伏寒藏于骨髓、肾,伏寒藏于肌肤等,以及热伏于经、血秽伏于命门、热毒伏于气血、胎毒伏于脾肺、疫气伏于膜原以及温毒遇温伏发等多种致病因素。并且,古代医家在阐述各种致疫因素的具体表现的同时,还提供了相应的治疗方法。明确病因是中医辨证论治的基础,横向挖掘疫病致病因素能更好地传承中医疫病理论精华,以期启发现代传染病的防控。文章为了解古代医家对疫病致病因素的理解和分类提供了一个全新的视角,对于理解和预防疫病具有重要的参考价值。

关键词：古代疫病致病因素类述