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具有时间不一致性偏好的扩散对偶模型的最优分红与注资问题（英文）

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南开大学学报（自然科学版） 2018年第1期51卷 79-90页

作者：王晓繁马世霞河北工业大学理学院天津300401

研究了带扩散的对偶模型中具有时间不一致性偏好的最优分红和注资问题,并假设管理者的这种时间不一致性偏好由准双曲贴现函数刻画.假设有比例交易费用,且可通过注资阻止破产发生,目标是使分红减去注资的累积现值期望最大化.当收益服从... 详细信息

研究了带扩散的对偶模型中具有时间不一致性偏好的最优分红和注资问题,并假设管理者的这种时间不一致性偏好由准双曲贴现函数刻画.假设有比例交易费用,且可通过注资阻止破产发生,目标是使分红减去注资的累积现值期望最大化.当收益服从指数分布时,得到了最优策略及最优值函数的解析式,并且发现具有时间不一致性偏好的管理者更倾向于提前分红.

关键词：时间不一致性对偶风险模型扩散分红与注资准双曲贴现函数

Controllable synthesis and spontaneous phase transition of photonic coordination polymer to produce a strong second-harmonic generation response

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Science China materials 2020年第7期63卷 1272-1278页

作者： Jun Zhang maierhaba Abudoureheman xiaofan ma Weili Kong Xiaopeng Xuan Shilie Pan School of materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China College of Chemistry and Chemical Engineering Key Laboratory of Coal Clean Conversion&Chemical Engineering ProcessCollege of Chemistry and Chemical EngineeringXinjiang UniversityUrumqi 830046China School of Chemistry and Chemical Engineering Key Laboratory of Green Chemical Media and ReactionsMinistry of EducationCollaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsHenan Normal UniversityXinxiang 453007China CAS Key Laboratory of Functional materials and Devices for Special Environments Xinjiang Technical Institute of Physics&ChemistryCASXinjiang Key Laboratory of Electronic Information Materials and DevicesUrumqi 830011China

Herein,a novel photonic coordination polymer material was constructed by aggregation-induced emission luminogen(AIEgen)containing a tripyridyl moiety used as the linking *** displayed a spontaneous direct centrosymmetric to noncentrosymmetric phase transition in a single *** two crystals,before and after the phase transition,were both controllably synthesized and characterized by single-crystal X-ray *** being exposed to air,the centrosymmetric metastable phase(1-α)transitioned to a new stable phase with a noncentrosymmetric structure(1-β).Interestingly,the 1-βstructure exhibited a strong phasematching second-harmonic generation(SHG)response,about4.5 times higher than that of KH2PO4(KDP).In order to better understand the relationship between the structure and the nonlinear optical properties,the dipole moments were calculated and ***,the noncentrosymmetric phase with high thermal stability for 1-βretained and improved the initial photoluminescent properties of the AIEgen ligand after the structural phase transition from 1-α,and simultaneously produced the excellent SHG property,which are beneficial for the design and construction of excellent optical materials.

关键词： second-harmonic generation controllable synthesis phase transition crystal structure single-crystal X-ray diffraction

基于核磁共振与无侧限抗压试验对纤维加固红黏土的宏微观特性研究

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铁道科学与工程学报 2021年第8期18卷 2066-2072页

作者：吕超马晓凡王颖广西桂禹工程咨询有限公司广西南宁530023 河海大学地球科学与工程学院江苏南京210098

红黏土因其具有孔隙比大、易压缩等不良工程特性,常在工程建设中引起一列工程问题。为此,采用聚丙烯纤维对红黏土进行加固,并采用核磁共振(NMR)技术和无侧限抗压强度试验对不同含量纤维加固后土体的宏微观特性进行测试,得到以下结论:1)... 详细信息

红黏土因其具有孔隙比大、易压缩等不良工程特性,常在工程建设中引起一列工程问题。为此,采用聚丙烯纤维对红黏土进行加固,并采用核磁共振(NMR)技术和无侧限抗压强度试验对不同含量纤维加固后土体的宏微观特性进行测试,得到以下结论:1)不同含量纤维加固后红黏土的T2谱形态基本保持一致,均在弛豫时间为1 ms附近出现峰值,且纤维含量为0.2%时,试样内部信号最强;不同含量纤维加筋土内部的孔径主要分布在0.01μm到0.05μm之间,且0.02μm孔径所占比例最大;试样的孔隙度和T2谱峰值面积随纤维含量的增加表现出先增加后减小的趋势,且均在纤维含量为0.2%时到达最大值;2)纤维能够明显增加红黏土的抗压强度,加筋土的抗压强度与纤维含量保持良好的线性增加关系;且随着纤维含量的增加,试样由脆性破坏逐渐表现为韧性破坏特征。3)纤维在土体中起到加筋作用,显著增加了土体间的连接力,且纤维相互交叉连接形成了空间网状结构,限制了土体的变形,使得加筋土抗压强度增加并表现出韧性破坏特征。

关键词：红黏土聚丙烯纤维核磁共振微观特性抗压强度

Research Progress on Application of Molecular markers in Breeding of Camellia oleifera

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Agricultural Biotechnology 2024年第3期13卷 1-4,10页

作者： Yimin HE Jingjing CHENG Dayu YANG Jiancai SHEN xiaofan ma Yali LI Ying ZHANG Hunan Academy of Forestry Changsha 410004China Institute of Tropical Agriculture and Forestry Hainan UniversityHaikou 570228China Dongying Shengli Jinhua Middle School Dongying 257000China

Camellia oleifera is an important woody oil tree species unique to *** is known as the world s four major woody oil crops along with olive,oil palm and *** is known as the‘king of oil’because of its high oil *** the increase of people's attention to the yield of Camellia oleifera,its high yield has become the *** traditional breeding model,judgment is performed by phenotypic traits,but this method is single and easily affected by the environment,and can no longer meet the *** contrast,molecular marker breeding is not affected by the environment,and is stable and efficient and capable of accurately mapping target genes,so it has attracted much *** this paper,the research progress on *** germplasm resources diversity,DNA fingerprinting construction,genetic linkage map construction and QTL mapping was summarized,and the application of SSR molecular marker technique combined with association analysis in *** breeding in recent years was discussed,in order to provide new ideas for high-yield breeding of ***.

关键词： Camellia oleifera Diversity SSR molecular marker technology Correlation analysis

Cloud Positioning System for Intelligent Connected Vehicle in Urban Area

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Cloud Positioning System for Intelligent Connected Vehicle i...

Critical climate issues toward carbon neutrality targets

2021中国汽车工程学会年会暨展览会

作者： Yue Bingjian Shi Shuming Yu Jianhua Jia Suhua ma xiaofan Lin Nan Transportation College of Jilin University Advanced Product Development Department of Dongfeng Commercial Vehicle Technology Center

Intelligent Connected Vehicles（ICVs） rely on positioning for a number of safety-critical *** Navigation Satellite System（GNSS）,alone or in combination with other device,is the most popular positioning *** to large noise,multi-path errors and the frequent rise and fall of satellites caused by propagation obstacles and mirror materials,the positioning availability and accuracy based on GNSS are heavily reduced in urban *** vehicular network,lots of location-related measurements are shared by *** fusion of these multisource measurements is an intelligent strategy for a more robust *** this context,we present a distributed fusion framework,Cloud Positioning System（CPS）,to augment the positioning *** 5 G V2 X communications,it is possible to simultaneously provide positioning service for hundreds of *** the purpose of showing information flow,we assume that the perfect association between vehicles and measurements is *** core estimation method of CPS is implemented by a Kalman Filter,which provides the upper bound of positioning performance compared to the practical algorithm with data *** availability is analysed by block diagram resulting that:when the availability of GNSS signal decreased from 99% to90%,the availability of CPS is still higher than 99%.

关键词： cooperative positioning vehicular network cloud computing availability

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Fundamental Research 2022年第3期2卷 396-400页

作者： Gang Huang Zhenhao Xu Xia Qu Junji Cao Shangmin Long Kai Yang Hongyu Hou Ya Wang xiaofan ma State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Laboratory for Regional Oceanography and NumericalModeling Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China International Polar Environment Research Laboratory College of OceanographyHohai UniversityNanjing 210098China

In 2020,China announced the"emission peak,carbon neutrality"policy,that is,China aims to have CO2 emissions peak before 2030 and achieve carbon neutrality before *** scenario of carbon neutrality will be significantly distinguished from the scenario we experienced since the industrial ***,instrumental data are unavailable in the future carbon-neutral *** system models and climate dynamics theory are needed to comprehend and project the climate *** this paper,we illustrate our perspective of the issues related to"emission peak,carbon neutrality",including climate dynamics,climate-carbon feedback,interaction between China and global climate and carbon emissions and solutions,*** highlight that climate change has profoundly affected human production and *** frequent occurrence of extreme weather disasters in recent years,together with the impact of epidemics,make the future"carbon peak&carbon-neutral"scenario more *** is whopping uncertainty but also a massive challenge to the scientific ***,carbon neutrality is closely related to domestic production and lives,and there is little time left for *** believe that we will make a breakthrough in climate dynamics in the context of carbon neutrality with our joint efforts,which will serve our country’s carbon emission policy at different stages.

关键词： Carbon neutrality Climate dynamics Climate-carbon feedback Diplomacy Possible solutions Future prospect

Detail correction for Gross classification of esophageal atresia based on 434 cases in China

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Chinese Medical Journal 2022年第4期135卷 485-487页

作者： Shen Yang Ruizhe Yang xiaofan ma Shuangfeng Yang Yun Peng Qiang Tao Kuai Chen Junfeng Tao Yanan Zhang Jingbin Du Jinshi Huang Xiaoxia Peng Department of Neonatal Surgery Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China Department of Otorhinolaryngology Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Radiology Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China Department of Neonatal Surgery The Affiliated Children’s Hospital of Nanchang UniversityNanchangJiangxi 330006China Center for Clinical Epidemiology and Evidence-based Medicine Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijing 100045China

To the Editor:Esophageal atresia(EA)is the most common congenital abnormality of the *** 70%to 90%of those born with EA,a tracheoesophageal fistula(TEF)*** Vogt[1]recognized and classified the types of anomalies in 1929,many other classification systems have been proposed,including the Ladd,Gross,Swenson,and Kluth classification systems.[2]However,the Gross classification of anatomical patterns of EA/TEF proposed in 1953 is one of the most widely accepted and used classification systems[3]and has been cited in Pediatric Surgery.[4]While surgical and imaging techniques have evolved considerably over recent decades,434 consecutive cases of EA/TEF in China were *** closely examining the imaging studies and the pathoanatomical configurations of these patients,we identified certain"defects"and details in the illustrations that need modification.

关键词： illustration details

湟水河流域景观格局变化对生态系统服务价值的影响研究

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环境污染与防治 2023年第5期45卷 626-633页

作者：马晓帆张海峰青海师范大学地理科学学院青海西宁810001 青藏高原地表过程与生态保育教育部重点实验室青海西宁810001 青海省自然地理与环境过程重点实验室青海西宁810001 高原科学与可持续发展研究院青海西宁810001

湟水河流域是青藏高原上重要的人类活动区域,改革开放后区域经济快速发展带来流域土地利用方式的显著变化,但对流域生态系统服务价值的影响尚未明确。基于湟水河流域1980—2020年土地利用数据,利用当量因子法、灰色关联度模型估算各土... 详细信息

湟水河流域是青藏高原上重要的人类活动区域,改革开放后区域经济快速发展带来流域土地利用方式的显著变化,但对流域生态系统服务价值的影响尚未明确。基于湟水河流域1980—2020年土地利用数据,利用当量因子法、灰色关联度模型估算各土地利用类型的生态系统服务价值(ESV),探究ESV与土地利用景观格局的关联程度。结果表明:(1)1980—2020年湟水河流域景观格局破碎程度持续加深,斑块多样性增加、分散化加剧;(2)湟水河流域ESV增加2.53亿元,增加0.58%,调节服务与支持服务价值是ESV的主要来源;(3)湟水河流域景观格局的破碎化程度、聚散特征和多样性与ESV的关联度较大,水体和建设用地的景观格局对调节服务价值、支持服务价值影响较大。控制建设用地、增加水体应是湟水河流域优化土地利用结构主要方式,有助于提升生态效益。

关键词：土地利用景观指数生态系统服务价值灰色关联

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包装纸箱废水处理技术研究

工业水处理 2011年第3期31卷 36-39页

作者：张志鹏韩相奎马小凡吉林大学环境与资源学院吉林长春130021 吉林建筑工程学院环境工程系吉林长春130000

包装纸箱废水成分复杂,有机物浓度较高,且含有大量的染料,可生化性差,处理难度较大。试验研究表明,该废水首先经沉淀处理,然后采用SBR工艺,在水温为26℃、pH为7左右、定期投放营养盐的条件下对其进行处理,可使废水COD从2200mg/L左右降至... 详细信息

包装纸箱废水成分复杂,有机物浓度较高,且含有大量的染料,可生化性差,处理难度较大。试验研究表明,该废水首先经沉淀处理,然后采用SBR工艺,在水温为26℃、pH为7左右、定期投放营养盐的条件下对其进行处理,可使废水COD从2200mg/L左右降至150mg/L以下,再经过次氯酸钠氧化,出水可实现达标排放。

关键词：包装纸箱废水沉淀序批式活性污泥法