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过去20年中国湖泊从CO_(2)源向汇转变

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Science Bulletin 2024年第12期69卷 1857-1861页

作者：肖启涛 Xiaofeng Xu 齐天赐罗菊花 Xuhui Lee 段洪涛 Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Biology Department San Diego State UniversitySan DiegoCA 92182USA School of the Environment Yale UniversityNew HavenCT 06511USA University of Chinese Academy of Sciences Nanjing(UCASNJ)Nanjing 211135China

Lakes emit large amounts of carbon dioxide(CO_(2))into the atmosphere with 0.81 Pg C a^(-1)[1],which offsets approximately24%of global land carbon ***,there is considerable uncertainty in the estimate due to limited data and the effects of human activity and climate *** China,lakes exhibit substantial variability in CO_(2)exchange,resulting in uncertainties in national and regional land carbon sink assessments.

关键词： change variability lakes

可重构智能表面辅助的V2I通信系统联合波束赋形算法

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电子与信息学报 2024年第8期46卷 3117-3125页

作者：仲伟志何艺段洪涛万诗晴范振雄朱秋明林志鹏南京航空航天大学电磁频谱空间认知动态系统工业与信息化部重点实验室南京211106 国家无线电监测中心北京100144

为解决基于信道先验知识的联合波束赋形方法受限于多变的车辆与交通基础设施(V2I)通信场景且信道估计开销过大等问题,该文结合环境态势感知,提出一种基于无线传播链路预测的联合波束赋形方法。该方法首先利用射线追踪模拟器构建了可重... 详细信息

为解决基于信道先验知识的联合波束赋形方法受限于多变的车辆与交通基础设施(V2I)通信场景且信道估计开销过大等问题,该文结合环境态势感知,提出一种基于无线传播链路预测的联合波束赋形方法。该方法首先利用射线追踪模拟器构建了可重构智能表面(RIS)辅助的V2I毫米波通信系统模型,通过改变环境态势以获取多样的无线传播链路数据来构建数据集。其次,使用该数据集训练基于机器学习的无线传播链路预测模型。最后,在最大发射功率约束条件下,构建了联合波束赋形问题模型,并基于预测结果采用交替迭代优化方法(AIOA)优化基站波束赋形矩阵和RIS相移矩阵,以实现同步通信车辆用户最小信干噪比(SINR)的最大化。仿真结果验证了该方法的有效性,通过引入非信道先验知识驱动,降低了信道探测开销,提高了该方法在V2I场景中的可行性。

关键词： V2I通信可重构智能表面联合波束赋形环境态势感知信道预测

典型农业流域不同类型池塘水体CO_(2)排放特征

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湖泊科学 2024年第1期36卷 88-98页

作者：陈嘉宁肖启涛刘臻婧肖薇谢晖罗菊花邱银国胡正华段洪涛南京信息工程大学气象灾害预报预警与评估协同创新中心南京210044 中国科学院南京地理与湖泊研究所中国科学院流域地理学重点实验室南京210008 湖南省气候中心长沙410118

内陆水体是大气CO_(2)收支估算的重要组成部分。农业流域分布着大量池塘景观水体,且具备蓄洪抗旱、消纳污染、水产养殖等多种功能。但是,农业流域不同功能的小型池塘CO_(2)排放特征尚不清楚。本研究以极具农业流域代表性的烔炀河流域为... 详细信息

内陆水体是大气CO_(2)收支估算的重要组成部分。农业流域分布着大量池塘景观水体,且具备蓄洪抗旱、消纳污染、水产养殖等多种功能。但是,农业流域不同功能的小型池塘CO_(2)排放特征尚不清楚。本研究以极具农业流域代表性的烔炀河流域为研究对象,选取流域中用于水产养殖(养殖塘)、生活污水承纳(村塘)、农业灌溉(农塘)、蓄水(水塘)的4个功能不同的景观池塘,基于为期1年的野外实地观测,以明确农业流域小型池塘CO_(2)排放特征。结果表明,不同功能池塘水体CO_(2)排放差异显著,受养殖活动、生活污水输入和农田灌溉等人类活动影响,养殖塘((80.37±100.39)mmol/(m^(2)·d))、村塘((48.69±65.89)mmol/(m^(2)·d))和农塘((13.50±15.81)mmol/(m^(2)·d))是大气CO_(2)的热点排放源,其CO_(2)排放通量分别是自然蓄水塘((4.52±23.26)mmol/(m^(2)·d))的18、11和3倍。统计分析也表明,该流域池塘CO_(2)排放变化总体上受溶解氧、营养盐等因素驱动。4个不同景观池塘CO_(2)排放通量全年均值为(37.31±67.47)mmol/(m^(2)·d),是不容忽视的CO_(2)排放源,其中养殖塘和村塘具有较高的CO_(2)排放潜力,在未来研究中需要重点关注。

关键词：农业流域池塘 CO_(2)通量影响因子

基于生成对抗网络的天线三维方向图室外测量方法

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数据采集与处理 2024年第4期39卷 886-897页

作者：兰天旭朱秋明白云鹏林志鹏吴启晖段洪涛吕冰南京航空航天大学电磁频谱空间认知动态系统工业与信息化部重点实验室南京211106 国家无线电监测中心北京100037

天线方向图测量是天线测量的重要内容。针对天线方向图室外测量困难的问题,提出了一种基于生成对抗网络的天线三维方向图室外测量方案。该方案利用无人机对天线方向图数据进行采集,对采集的数据进行修正,获得待测天线和接收天线极化匹... 详细信息

天线方向图测量是天线测量的重要内容。针对天线方向图室外测量困难的问题,提出了一种基于生成对抗网络的天线三维方向图室外测量方案。该方案利用无人机对天线方向图数据进行采集,对采集的数据进行修正,获得待测天线和接收天线极化匹配时的直射径数据,最后利用训练好的生成对抗网络重构出天线的三维方向图。仿真结果表明,本方案可以高效、高精度地完成天线三维方向图的测量,具有一定的实用价值。

关键词：天线方向图无人机生成对抗网络射线追踪误差修正

Catchment-based Imperviousness Metrics Impacts on Floods in Niushou River Basin,Nanjing City,East China

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Chinese Geographical Science 2017年第2期27卷 229-238页

作者： SU Weizhong duan hongtao Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China

Concerns regarding urbanization impacts on floods gradually moved from end-of-pipe solutions, based on open channel hydraulics improvement, to imperviousness ratio limiting and then to land use control and to integrated planning at local and large scale levels. The Niushou River basin is one of the fastest urbanizing areas in Nanjing City, East China, however, the high urban land percentage has leaded to series of flooding events. The paper aims to reveal the impact of imperviousness ratio, patterns and drainage system on flooding areas based on the unit of catchment and Storm Water Management Model(SWMM). The following conclusions were reached. 1) The ratio or spatial characteristics of the impervious surface affected the runoff volumes and associated floods areas. Despite the well-established drainage system, the high imperviousness ratio, particularly clustered pattern in locations such as hydrological sensitive zones aggravated the flooding tension across the basin. 2) The poor drainage hydraulic efficiency in local areas, and the lack of integral processes of infiltration, yield, storage and discharge in local catchment and larger basin are also significant factors. 3) The Niushou River basin development should improve the drainage transformations from a single local, short-term drainage process into integral, elastic processes of infiltration, yield, storage, and discharge.

关键词：透不过比率(红外) 透不过模式充满区域集水系统 Niushou 河盆

Neurophysiological, histological, and behavioral characterization of animal models of distraction spinal cord injury: a systematic review

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Neural Regeneration Research 2024年第3期19卷 563-570页

作者： Bo Han Weishi Liang Yong Hai duan Sun hongtao Ding Yihan Yang Peng Yin Department of Orthopedics Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina

Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal *** the increased degree and duration of distraction,spinal cord injuries become more serious in terms of their neurophysiology,histology,and *** few studies have been published on the specific characteristics of distraction spinal cord *** this study,we systematically review 22 related studies involving animal models of distraction spinal cord injury,focusing particularly on the neurophysiological,histological,and behavioral characteristics of this *** addition,we summarize the mechanisms underlying primary and secondary injuries caused by distraction spinal cord injury and clarify the effects of different degrees and durations of distraction on the primary injuries associated with spinal cord *** provide new concepts for the establishment of a model of distraction spinal cord injury and related basic research,and provide reference guidelines for the clinical diagnosis and treatment of this disease.

关键词： animal models behavior distraction heterogeneity histology mechanism neurophysiology spinal cord injury systematic review tension

Static magnetic field-assisted synthesis of Fe3O4 nanoparticles and their adsorption of Mn(Ⅱ) in aqueous solution

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Chinese Journal of Chemical Engineering 2017年第1期25卷 32-36页

作者： Yong Liu Jianfei Bai hongtao duan Xiaohong Yin College of Chemistry and Chemical Engineering Tianjin University of Technology Tianjin 300384 China Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion Tianjin University of Technology Tianjin 300384 China

A facile method for synthesis of the magnetic Fe_3O_4 nanoparticles was *** nanoparticles were prepared via co-precipitation method with(PMF) and without(AMF) 0.15 T static magnetic *** effects of magnetic field on the properties of magnetic nanoparticles were studied by XRD,TEM,SEM,VSM and *** results showed that the magnetic field in the co-precipitation reaction process did not result in the phase change of the Fe_3O_4 nanoparticles but improved the *** morphology of Fe_3O_4 nanoparticles was varied from random spherical particles to rod-like cluster *** VSM results indicated that the saturation magnetization value of the Fe_3O_4 nanoparticles was significantly improved by the magnetic *** BET of Fe_3O_4nanoparticles prepared with the magnetic field was larger than the control by 23.5%.The batch adsorption experiments of Mn(Ⅱ) on the PMF and AMF Fe_3O_4 nanoparticles showed that the Mn(II) equilibrium capacity was increased with the pH value *** pH 8,the Mn(Ⅱ) adsorption capacity for the PMF and AMF Fe_3O_4 was reached at 36.81 and 28.36 mg·g^(-1),*** pseudo-second-order model fitted better the kinetic models and the Freundlich model fitted isotherm model well for both PMF and AMF Fe_3O_*** results suggested that magnetic nanoparticles prepared by the magnetic field presented a fairly good potential as an adsorbent for an efficient removal of Mn(Ⅱ) from aqueous solution.

关键词：纳米Fe3O4 Mn(Ⅱ) 静态磁场辅助合成吸附实验水溶液 Fe3O4纳米粒子磁性纳米粒子

Output Feedback Robust H_(∞) Control for Discrete 2D Switched Systems

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Computer Systems Science & Engineering 2021年第10期39卷 69-85页

作者： Wenjun Gao Yang Yang hongtao duan Mingsheng Li Jinrong Ma Songwei Jin School of Electronic Information and Engineering Changchun University of Science and TechnologyChangchun130000China Department of Computer Science and Engineering University of CaliforniaRiversideCA92521USA

The two-dimensional(2-D)system has a wide range of applications in different fields,including satellite meteorological maps,process control,and digital ***,the research on the stability of 2-D systems is of great *** that multiple systems exist in switching and alternating work in the actual production process,but the system itself often has external perturbation and *** solve the above problems,this paper investigates the output feedback robust H_(∞)stabilization for a class of discrete-time 2-D switched systems,which the Roesser model with uncertainties ***,sufficient conditions for exponential stability are derived via the average dwell time method,when the system’s interference and external input are ***,in the case of introducing the external interference,the weighted robust H_(∞)disturbance attenuation performance of the underlying system is further *** output feedback controller is then proposed to guarantee that the resulting closed-loop system is exponentially stable and has a prescribed disturbance attenuation levelγ.All theorems mentioned in the article will also be given in the form of linear matrix inequalities(LMI).Finally,a numerical example is given,which takes two uncertain values respectively and solves the output feedback controller’s parameters by the theorem proposed in the *** to the required controller parameter values,the validity of the theorem proposed in the article is compared and verified by simulation.

关键词： 2-D systems robust H_(∞)control LMI output feedback switched systems Roesser model

Remote determination of chromophoric dissolved organic matter in lakes, China

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International Journal of Digital Earth 2014年第11期7卷 897-915页

作者： Guangjia Jiang Ronghua Ma hongtao duan Steven A.Loiselle Jingping Xu Dianwei Liu State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjingChina University of Chinese Academy of Sciences BeijingChina Dipartimento Farmaco Chimico Tecnologico CSGIUniversity of SienaSienaItaly Northeast Institute of Geography and Agricultural Ecology Chinese Academy of SciencesChangchunChina

Chromophoric dissolved organic matter(CDOM)strongly influences the water-leaving radiance from aquatic *** most inland waters,the remote determination of CDOM absorption presents a central challenge due to their complex optical ***,identifying the temporal and spatial variability of CDOM is fundamental to the understanding of aquatic biogeo-chemical *** the present study,semi-analytical and empirical modeling approaches were used to examine CDOM absorption in four,shallow,inland water bodies using the spectral bands and sensitivities of major satellite observational *** the models examined,an empirical multiband model was found to provide the highest correlation with measured CDOM *** spectral characteristics of the MERIS sensors yielded the best results with respect to the other available satellite *** detrital load was observed to be a major impediment to estimating CDOM absorption,while lakes with elevated phytoplankton biomass did not present similar problems.

关键词： inland waters remote sensing lake carbon DOC absorption