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基于误比特信息区间斜率的正交频分复用水声通信多普勒估计

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声学学报 2024年第3期49卷 560-568页

作者：李斌童峰姚俊辉陈建峰福建理工大学智慧海洋科学技术学院福州350118 导航与位置服务技术国家地方联合工程研究中心(厦门大学) 厦门361002 厦门大学海洋与地球学院厦门361002 西安天和海防智能科技有限公司西安710061

针对正交频分复用水声通信中直接误比特率搜索多普勒估计算法存在的高计算复杂度问题,提出了一种基于误比特信息区间斜率的多普勒估计算法,采用计算误比特信息区间斜率取代逐网格搜索最优误比特信息寻优过程,设计根据多普勒估计分辨率... 详细信息

针对正交频分复用水声通信中直接误比特率搜索多普勒估计算法存在的高计算复杂度问题,提出了一种基于误比特信息区间斜率的多普勒估计算法,采用计算误比特信息区间斜率取代逐网格搜索最优误比特信息寻优过程,设计根据多普勒估计分辨率动态可变的斜率区间,在进一步提升寻优速率的同时有效减小陷入局部最优解的可能性,并有效降低算法的计算复杂度。仿真实验和海上试验结果表明:所提算法以较低的计算代价实现了与误比特率搜索多普勒估计算法近乎一致的估计性能,在本文试验条件下其相对块多普勒估计、基于互模糊度函数多普勒估计以及准梯度互相关多普勒估计算法可获得不低于14%的误比特率性能改善。

关键词：多普勒估计区间斜率误比特信息正交频分复用水声通信

The Clumpy Structure of Five Star-bursting Dwarf Galaxies in the MaNGA Survey

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Research in Astronomy and Astrophysics 2024年第2期24卷 83-103页

作者： Mengting Ju Jun Yin Lei Hao Chenxu Liu Chao-Wei Tsai Junfeng Wang Zhengyi Shao Shuai feng Yu Rong Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China Key Lab for Astrophysics Shanghai 200034China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Department of Astronomy Physics BuildingXiamen UniversityXiamenFujian 361005China College of Physics Hebei Normal UniversityShijiazhuang 050024China Hebei Key Laboratory of Photophysics Research and Application Shijiazhuang 050024China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

The star-forming clumps in star-bursting dwarf galaxies provide valuable insights into understanding the evolution of dwarf galaxies.In this paper,we focus on five star-bursting dwarf galaxies featuring off-centered clumps in the Mapping Nearby Galaxies at Apache Point Observatory survey.Using the stellar population synthesis software Fitting Analysis using Differential evolution Optimization,we obtain the spatially resolved distribution of the star formation history,which allows us to construct the g-band images of the five galaxies at different ages.These images can help us to probe the evolution of the morphological structures of these galaxies.While images of a stellar population older than 1 Gyr are typically smooth,images of a stellar population younger than 1 Gyr reveal significant clumps,including multiple clumps which appear at different locations and even different ages.To study the evolutionary connections of these five galaxies to other dwarf galaxies before their star-forming clumps appear,we construct the images of the stellar populations older than three age nodes,and define them to be the images of the"host"galaxies.We find that the properties such as the central surface brightness and the effective radii of the hosts of the five galaxies are in between those of dwarf ellipticals(dEs)and dwarf irregulars(dIrrs),with two clearly more similar to dEs and one more similar to dIrrs.Among the five galaxies,8257-3704 is particularly interesting,as it shows a previous starburst event that is not quite visible from its gri image,but only visible from images of the stellar population at a few hundred million years.The star-forming clump associated with this event may have appeared at around 600 Myr ago and disappeared at around 40 Myr ago.

关键词： galaxies dwarf-galaxies evolution-galaxies formation-Galaxy structure

基于流域系统模拟一情景优化的精细治理决策支持方法

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地理学报 2024年第1期79卷 58-75页

作者：秦承志朱良君申申吴彤肖桂荣吴升陈芸芝汪小钦冯险峰朱阿兴陆锋中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101 中国科学院大学资源与环境学院北京100049 数字中国研究院(福建) 福州350108 福州大学空间数据挖掘与信息共享教育部重点实验室福州350108 南京师范大学地理科学学院南京210023 威斯康星大学麦迪逊分校地理系美国麦迪逊WI 53706

面向美丽中国生态文明建设所需,亟待有效实现流域精细治理的科学决策,以根据流域综合治理愿景目标,优化流域管理措施(BMP)的空间布局方案(即BMP情景)、制定符合实际需求的实施路线图。对此,“流域系统模拟—情景优化”方法框架近年展现... 详细信息

面向美丽中国生态文明建设所需,亟待有效实现流域精细治理的科学决策,以根据流域综合治理愿景目标,优化流域管理措施(BMP)的空间布局方案(即BMP情景)、制定符合实际需求的实施路线图。对此,“流域系统模拟—情景优化”方法框架近年展现出广阔应用前景。本文介绍了该框架在应对实际应用需求中尚存的一系列问题,开展了体系性的方法研究:①提出新的流域过程建模框架,以兼顾建模灵活性和高性能计算、高效实现流域系统模拟;②提出以坡位单元作为BMP空间配置单元、并在情景优化过程中可进行单元边界动态调整的BMP情景优化方法,可有效考虑流域综合治理的经验知识,保障优化结果合理性;③提出考虑分阶段投资约束的BMP情景实施次序优化方法,可推荐出符合实际落地需求的实施路线图;④设计研发用户友好的参与式流域规划系统,供各方利益相关者协商决策。通过典型小流域应用案例验证了上述新方法、工具和原型系统的有效性和实用价值。

关键词：流域系统模拟流域管理措施情景分析智能优化决策支持

Incidence and prognosis of olfactory and gustatory dysfunctions related to SARS-CoV-2 Omicron strain infection in China:A national multicenter survey of 35,566 individuals

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 113-120页

作者： Meng-Fan Liu Rui-Xia Ma Xian-Bao Cao Hua Zhang Shui-Hong Zhou Wei-Hong Jiang Yan Jiang Jing-Wu Sun Qin-Tai Yang Xue-Zhong Li Ya-Nan Sun Li Shi Min Wang Xi-Cheng Song Fu-Quan Chen Xiao-Shu Zhang Hong-Quan Wei Shao-Qing Yu Dong-Dong Zhu Luo Ba Zhi-Wei Cao Xu-Ping Xiao Xin Wei Zhi-Hong Lin feng-Hong Chen Chun-Guang Shan Guang-Ke Wang Jing Ye Shen-Hong Qu Chang-Qing Zhao Zhen-Lin Wang Hua-Bin Li feng Liu Xiao-Bo Cui Sheng-Nan Ye Zheng Liu Yu Xu Xiao Cai Wei Huang Ru-Xin Zhang Yu-Lin Zhao Guo-Dong Yu Guang-Gang Shi Mei-Ping Lu Yang Shen Yu-Tong Zhao Jia-Hong Pei Shao-Bing Xie Long-Gang Yu Ye-Hai Liu Shao-Wei Gu Yu-Cheng Yang Lei Cheng Jian-feng liu Graduate School of Beijing University of Chinese Medicine BeijingChina Department of Otorhinolaryngology Head and Neck Surgery China-Japan Friendship HospitalBeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First People's Hospital of YinchuanYinchuanChina Department of Otorhinolaryngology The First People's Hospital of Yunnan ProvinceKunmingChina Department of Otorhinolaryngology The First Affiliated Hospital of Xinjiang Medical UniversityUrumqiChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina Department of Otorhinolaryngology Head and Neck Surgery Xiangya Hospital Central South UniversityChangshaChina Department of Otorhinolaryngology Head and Neck Surgery The Affiliated Hospital of Qingdao UniversityQingdaoChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of USTCHefeiChina Department of Otorhinolaryngology Head and Neck Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouChina Department of Otorhinolaryngology Head and Neck Surgery Qilu Hospital of Shandong UniversityJinanChina Department of Otorhinolaryngology Head and Neck Surgery The Second Affiliated Hospital of Harbin Medical UniversityHarbinChina Department of Otolaryngology The Second Hospital of Shandong UniversityShandong UniversityJinanChina Department of Otorhinolaryngology Head and Neck Surgery Peking University People's HospitalBeijingChina Department of Otorhinolaryngology Head and Neck Surgery Yantai Yuhuangding HospitalQingdao UniversityYantaiChina Department of Otorhinolaryngology Head and Neck Surgery Xijing HospitalThe Fourth Military Medical UniversityXi'anChina Gansu Provincial Center for Disease Control and Prevention LanzhouChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of China Medical UniversityShenyangChina Department of Otorhinolaryngology Head and Neck Surgery Tongji Hospit

Objective:This cross-sectional study aimed to determine the epidemiology of olfactory and gustatory dysfunctions related to COVID-19 in China.Methods:This study was conducted by 45 tertiary Grade-A hospitals in China.Online and offline questionnaire data were obtained from patients infected with COVID-19 between December 28,2022,and February 21,2023.The collected information included basic demographics,medical history,smoking and drinking history,vaccination history,changes in olfactory and gustatory functions before and after infection,and other postinfection symptoms,as well as the duration and improvement status of olfactory and gustatory disorders.Results:Complete questionnaires were obtained from 35,566 subjects.The overall incidence of olfactory and taste dysfunction was 67.75%.Being female or being a cigarette smoker increased the likelihood of developing olfactory and taste dysfunction.Having received four doses of the vaccine or having good oral health or being a alcohol drinker decreased the risk of such dysfunction.Before infection,the average olfactory and taste VAS scores were 8.41 and 8.51,respectively;after infection,they decreased to 3.69 and 4.29 and recovered to 5.83 and 6.55 by the time of the survey.The median duration of dysosmia and dysgeusia was 15 and 12 days,respectively,with 0.5%of patients having symptoms lasting for more than 28 days.The overall self-reported improvement rate was 59.16%.Recovery was higher in males,never smokers,those who received two or three vaccine doses,and those that had never experienced dental health issues,or chronic accompanying symptoms.Conclusions:The incidence of dysosmia and dysgeusia following infection with the SARS-CoV-2 virus is high in China.Incidence and prognosis are influenced by several factors,including sex,SARS-CoV-2 vaccination,history of head-facial trauma,nasal and oral health status,smoking and drinking history,and the persistence of accompanying symptoms.

关键词： epidemiologic studies incidence olfactory disorders prognosis SARS-CoV-2 taste disorders

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颅缝发育与颅缝早闭的分子机制

中国生物化学与分子生物学报 2024年第2期40卷 151-159页

作者：叶剑青胡雪峰福建师范大学生命科学学院福建省发育与神经生物学重点实验室福州350117

颅骨的发育依赖于颅缝(cranial suture)正常的骨供给,期间颅缝的间充质干细胞经历系统地增殖和成骨分化以保证骨的正常生长。遗传因素或外界干扰则可能引起干细胞的过度成骨分化,导致颅骨的过早闭合,称为颅缝早闭。颅缝细胞与细胞外基... 详细信息

颅骨的发育依赖于颅缝(cranial suture)正常的骨供给,期间颅缝的间充质干细胞经历系统地增殖和成骨分化以保证骨的正常生长。遗传因素或外界干扰则可能引起干细胞的过度成骨分化,导致颅骨的过早闭合,称为颅缝早闭。颅缝细胞与细胞外基质、骨膜以及脑膜共同构成颅缝微环境(niche)。它们相互调节以保证颅缝的正常发育。临床研究发现,绝大多数颅缝早闭(craniosynostosis)患者都伴有硬脑膜和细胞外基质(extracellular matrixc,ECM)的异常。许多研究也发现,作用于颅缝的异常外界机械刺激也可能导致颅缝发育的异常。考虑到颅缝发育受多方面因素影响,本篇综述将介绍近年来有关颅缝微环境异常,以及机械力在调控颅缝发育中的研究进展,总结颅缝早闭发生的分子机制和目前研究方向,旨在为该病的诊断治疗提供新的思路。

关键词：颅缝早闭硬脑膜细胞外基质机械力

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富锌排铅咀嚼片安全性毒理学评价

广东微量元素科学 2006年第11期13卷 27-34页

作者：冯福建王五一虞江萍扬林生李永华中国科学院地理科学与资源研究所北京100101

对富锌排铅咀嚼片(RZLR)进行了急性毒性试验、Ames试验、骨髓微核试验、精子畸形试验和30 d喂养试验。结果表明,小鼠急性毒性LD50(BW)>21 500 mg/kg,属无毒级;Ames试验、小鼠骨髓微核试验、精子畸形试验和30 d喂养试验结果均为阴性;30 ... 详细信息

对富锌排铅咀嚼片(RZLR)进行了急性毒性试验、Ames试验、骨髓微核试验、精子畸形试验和30 d喂养试验。结果表明,小鼠急性毒性LD50(BW)>21 500 mg/kg,属无毒级;Ames试验、小鼠骨髓微核试验、精子畸形试验和30 d喂养试验结果均为阴性;30 d喂养试验也未显示明显毒性。本研究证实RZLR是一种安全、无毒副作用的保健食品。

关键词：毒理学评价保健食品富锌排铅咀嚼片

二维剪切波弹性成像和血清学模型在慢性乙型肝炎患者肝纤维化分期中的应用价值

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临床肝胆病杂志 2024年第3期40卷 509-515页

作者：黄玉洁冯斯奕福建医科大学孟超肝胆医院超声科福州350001

目的探讨二维剪切波弹性成像和血清学模型及其联合应用在慢性乙型肝炎患者肝纤维化分期中的诊断价值。方法回顾性分析2020年8月—2022年8月在福建医科大学孟超肝胆医院进行过二维剪切波弹性成像(2D-SWE)与肝组织病理学检查的327例慢... 详细信息

目的探讨二维剪切波弹性成像和血清学模型及其联合应用在慢性乙型肝炎患者肝纤维化分期中的诊断价值。方法回顾性分析2020年8月—2022年8月在福建医科大学孟超肝胆医院进行过二维剪切波弹性成像(2D-SWE)与肝组织病理学检查的327例慢性乙型肝炎患者的临床资料,提取患者的性别、年龄、血清学指标和2D-SWE结果,根据肝纤维化程度分为S0~S1组、S≥2组、S≥3组和S=4组,根据血清学指标计算血清学模型。采用Spearman相关分析法对2D-SWE和血清学模型与肝纤维化分期进行相关分析,以肝组织病理结果为标准,绘制受试者工作特征曲线,比较各参数及其联合应用诊断肝纤维化分期的效能,并采用Delong检验比较不同方法间的差异。结果 2D-SWE检测LSM值与肝纤维化分期呈强相关性(r=0.741,P0.05)。结论 2D-SWE对肝纤维化分期的诊断效能显著优于7种血清学模型;血清学模型具有一定的诊断价值,其中APRI、S指数的价值较高;单独使用2D-SWE与指标联合并无明显差异,联合并不能显著提高诊断效能,新的联合诊断方法仍有待探索。

关键词：慢性乙型肝炎肝纤维化弹性成像技术活组织检查,针吸

Bi_(2)(Se_(0.53)Te_(0.47))_(3)纳米线的制备及其圆偏振光致电流效应

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福州大学学报（自然科学版） 2024年第1期52卷 14-19页

作者：冯世尊俞金玲福州大学物理与信息工程学院福建福州350108

采用化学气相沉积法制备Bi_(2)(Se_(0.53)Te_(0.47))_(3)纳米线,利用扫描电子显微镜和X射线能谱仪对其进行表征,并研究样品的圆偏振光致电流效应(circular photogalvanic effect, CPGE).利用1 064 nm激光激发,分别测试激光入射面垂直于... 详细信息

采用化学气相沉积法制备Bi_(2)(Se_(0.53)Te_(0.47))_(3)纳米线,利用扫描电子显微镜和X射线能谱仪对其进行表征,并研究样品的圆偏振光致电流效应(circular photogalvanic effect, CPGE).利用1 064 nm激光激发,分别测试激光入射面垂直于纳米线和平行于纳米线时的CPGE电流.实验结果表明,测得的CPGE电流主要来自纳米线的拓扑表面态.激光垂直入射纳米线时的CPGE电流不为0,说明CPGE电流来源于纳米线能带的六角翘曲效应.本研究测得的Bi_(2)(Se_(0.53)Te_(0.47))_(3)纳米线的CPGE电流比文献报导的Bi2(Te0.23Se0.77)3纳米线增大2倍以上,这是因为Te组分的增加不但使得费米能级更加靠近狄拉克点,还降低了纳米线中载流子复合的概率,二者共同作用,使得CPGE电流增大.

关键词： Bi_(2)(Se_(0.53)Te_(0.47))_(3)纳米线拓扑绝缘体化学气相沉积圆偏振光致电流效应

中国旅游生态韧性空间关联网络结构及其驱动因素

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地理研究 2024年第5期43卷 1146-1165页

作者：李志远冯学钢何静左文俊华东师范大学经济与管理学院上海200062 乌拉尔联邦大学高等经济与管理学院俄罗斯叶卡捷琳堡620002

在生态文明建设的新时期,合理评估旅游生态系统是反映旅游产业是否彰显绿色动能及迈向可持续发展之路的重要表征,从“韧性”视角切入,能凸显旅游生态系统复合性及动态演化特征。本文以2011—2020年中国31省(自治区、直辖市)为研究对象,... 详细信息

在生态文明建设的新时期,合理评估旅游生态系统是反映旅游产业是否彰显绿色动能及迈向可持续发展之路的重要表征,从“韧性”视角切入,能凸显旅游生态系统复合性及动态演化特征。本文以2011—2020年中国31省(自治区、直辖市)为研究对象,构建旅游生态韧性综合指标体系并测度其发展水平,借助修正引力模型测度空间关联强度,运用社会网络分析法对其空间关联网络结构及驱动因素进行分析。结果表明:(1)中国省际整体旅游生态韧性水平呈现稳态攀升的态势,区域上呈现“东部领衔,中西部追赶”的布局特征;空间关联网络呈现向复杂化、稠密化演化的过程,“东密西疏”的空间特征突出。(2)整体网络结构渐趋紧密,但尚未达到最佳空间关联状态;东部地在空间关联网络中处于核心主导地位,中西部部分地区处于空间网络结构的边缘地带。(3)苏、沪、京、津为“净受益”板块,浙、粤、闽充当“经纪人”角色,晋、冀等地区属于“双向溢出”板块,新、藏、贵、滇等地区属于“净溢出”板块。(4)环境规制力度、产业高级化、空间距离、经济水平、科技创新、对外开放差异均对中国旅游生态韧性空间关联效应发挥着正向作用,在多重效应叠加的背景下,旅游产业绿色动能持续彰显,关联特征愈发明显。上述结论回应了旅游可持续发展与生态文明建设高质量互动的学术关切,为提升旅游生态系统韧性并加强与其他地区的空间互动提供了重要导引。

关键词：旅游生态系统旅游生态韧性空间关联网络社会网络分析驱动因素作用路径