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Comprehensive understanding on sources of high levels of fine particulate nitro-aromatic compounds at a coastal rural area in northern China

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Journal of Environmental Sciences 2024年第1期135卷 483-494页

作者： Yueru Jiang Xinfeng Wang Min Li Yiheng Liang Zhiyi Liu Jing Chen Tianyi Guan jiangshan Mu Yujiao Zhu He Meng Yang Zhou Lan Yao Likun Xue Wenxing Wang Environment Research Institute Shandong UniversityQingdao 266237China Department of Environmental Systems Science Swiss Federal Institute of Technology ZurichZurich 8092Switzerland Department of Water Resources and Drinking Water Swiss Federal Institute of Aquatic Science and TechnologyDuebendorf 8600Switzerland Qingdao Eco-Environment Monitoring Center of Shandong Province Qingdao 266003China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200234China

Nitro-aromatic compounds(NACs)are among the major components of brown carbon(BrC)in the atmosphere,causing negative impacts on regional climate,air quality,and ecological *** to the extensive origins,it is still a challenge to figure out the contributions and originating regions for different sources of atmospheric ***,field observations on fine particulate NACs were conducted at a coastal rural area in Qingdao,China in the winter of 2018 and *** mean total concentrations of fine particulate nitro-aromatic compounds were 125.0±89.5 and 27.7±21.1 ng/m^(3)in the winter of 2018 and 2019,*** the measured eleven NACs,nitrophenols and nitrocatechols were the most abundant *** characteristics and correlation analysis showed that humidity and anthropogenic primary emissions had significant influences on the NAC *** this study,two tracing methods of the improved spatial concentration weighted trajectory(SCWT)model and the receptor model of positive matrix factorization(PMF)were combined to comprehensively understand the origins of NACs in fine particles at coastal *** major sources were identified,including coal combustion,biomass burning,vehicle exhaust,and secondary ***,coal combustion was responsible for about half of the observed nitro-aromatic compounds,followed by biomass burning(~30%).The results by SCWT demonstrated that the coal combustion dominated NACs mainly originated from the Shandong peninsula and the areas to the north and southwest,while those dominated by biomass burning primarily came from local Qingdao and the areas to the west.

关键词： Nitro-aromatic compounds Fine particles Source apportionment Originating region Combustion activities

敦煌写卷S.2702《净名经集解》卷背诸内容之关联性分析

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敦煌研究 2015年第2期 59-64页

作者：冷江山贵州师范大学文学院贵州贵阳550001

S.2702《净名经集解》抄卷是一个典型的讲经和俗讲活动所用的"底本",卷中有些内容看似偶然抄在一起,但从俗讲特点以及讲经与俗讲的关系等视角来看,它们之间都存在实际应用方面的相互关联,整个写卷大致可以再现当时的讲唱过程。

关键词：敦煌写卷佛教俗讲同抄关联

Light Meson PDFs from BLFQ and QCD Evolution

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IMP & HIRFL Annual Report 2018年第1期 25-26页

作者： Lan jiangshan Mondal Chandan Xu Siqi Zhao Xingbo 不详

The basis light front quantization(BLFQ)is a nonperturbative approach for the light front wavefunctions(LFWFs)and the spectroscopy of the many body bound-state systems in quantum field theories[1−3].It is a Hamiltonian-based formalism with the advantages of light front dynamics[4].The LFWFs of the bound states are obtained as the eigenfunctions of the light front Schr¨odinger equation Heff|Ψ>=M2|Ψ>,where Heff is the effective Hamiltonian of the system.

关键词： Hamiltonian light quantum

High efficiency yellow fluorescent organic light emitting diodes based on m-MTDATA/BPhen exciplex

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Frontiers of Optoelectronics 2015年第4期8卷 439-444页

作者： Liping ZHU Kai XU Yanping WANG jiangshan CHEN Dongge MA State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of the Chinese Academy of Sciences Changchun 130022 China

High efficient yellow organic light emitting diodes （OLEDs） based on exciplex were reported. The exciplex was formed by 4, 4＇, 4″-tris β-methylphenyl （phenyi） amino]-triphenylamine （m-MTDATA） and 4, 7- diphenyl-1, 10-phenanthroline （BPhen）. The resulting yellow OLEDs exhibited an external quantum efficiency of over 7%, which is attributed to the effective energy back transfer from exciplex triplet state to exciplex singlet state. The maximum power efficiency of 25 lm/W was achieved. Doping a yellow phosphor Ir（bt）2（acac） into m-MTDATA： BPhen blend, a high efficiency device was achieved with a turn-on voltage of 2.1 V, maximum power efficiency and external quantum efficiency of 86.1 lm/W and 20.7%, respectively.

关键词： organic light-emitting diodes (OLEDs) fluor-escent exciplex

Predicting Credit Card Transaction Fraud Using Machine Learning Algorithms

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Journal of Intelligent Learning Systems and Applications 2019年第3期11卷 33-63页

作者： Jiaxin Gao Zirui Zhou jiangshan Ai Bingxin Xia Stephen Coggeshall Hebei University of Economics and Business Shijiazhuang China China University of Political Science and Law Beijing China Wuhan Maple Leaf International School (High School) Wuhan China Wuhan Jinde Education Consulting Co. Ltd. Wuhan China University of Southern California Los Angeles USA

Credit card fraud is a wide-ranging issue for financial institutions, involving theft and fraud committed using a payment card. In this paper, we explore the application of linear and nonlinear statistical modeling and machine learning models on real credit card transaction data. The models built are supervised fraud models that attempt to identify which transactions are most likely fraudulent. We discuss the processes of data exploration, data cleaning, variable creation, feature selection, model algorithms, and results. Five different supervised models are explored and compared including logistic regression, neural networks, random forest, boosted tree and support vector machines. The boosted tree model shows the best fraud detection result (FDR = 49.83%) for this particular data set. The resulting model can be utilized in a credit card fraud detection system. A similar model development process can be performed in related business domains such as insurance and telecommunications, to avoid or detect fraudulent activity.

关键词： Credit Card Fraud Machine Learning Algorithms Logistic Regression Neural Networks Random Forest Boosted Tree Support Vector Machines

Comparison of aircraft observations with ensemble forecast model results in terms of the microphysical characteristics of stratiform precipitation

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Atmospheric and Oceanic Science Letters 2020年第5期13卷 452-461页

作者： FU Yuan LEI Hengchi YANG Jiefan GUO Jiaxu ZHU jiangshan Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary Science University of Chinese Academy of SciencesBeijingChina

The prediction of the particle number concentration and liquid/ice water content of cloud is significant for many aspects of atmospheric ***,given the uncertainties in the initial and boundary conditions and imperfections of microphysical schemes,the accurate prediction of these microphysical properties of cloud is still a big *** ensemble approach may be a viable way to reduce forecast *** this paper,a large-scale stratiform cloud precipitation process is studied by comparing results of a 10-member ensemble forecast model with aircraft observation *** means of the ensemble average,the prediction of bulk parameters such as liquid water content and ice water content can be improved in comparison with the control member,but the particle number concentrations are still one to two orders of magnitude less than those from *** of raindrop size spectra reveals a big distinction between observations and predictions for particles with a diameter less than 1000μm.

关键词： Aircraft observation ensemble forecast model particle number concentration liquid/ice water content

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棒材在线计数中断面定位方法研究

仪器仪表学报 2010年第5期31卷 1173-1178页

作者：张达谢植艾江山北京矿冶研究总院北京100044 东北大学信息科学与工程学院沈阳110004 中南大学长沙410083

研究了棒材在线计数系统中单帧棒材断面图像的增强和棒材信息检出问题,主要提出了两步法:首先通过光学系统对棒材断面进行预增强,然后通过模板匹配和变阈值分割混合方法实现棒材断面中心定位,进而实现棒材位置信息提取,为后续棒材目标... 详细信息

研究了棒材在线计数系统中单帧棒材断面图像的增强和棒材信息检出问题,主要提出了两步法:首先通过光学系统对棒材断面进行预增强,然后通过模板匹配和变阈值分割混合方法实现棒材断面中心定位,进而实现棒材位置信息提取,为后续棒材目标的跟踪和计数工作打好基础。现场应用结果表明:本方法能够有效克服杂光和快速运动带来的图像模糊、氧化带来的断面发蓝变暗、棒材未对齐带来的遮挡黏连以及棒材侧壁和噪声干扰等情况的影响,实现对于采集的棒材图像中棒材断面中心位置的可靠提取,测量偏差小于万分之一。

关键词：棒材在线计数图像增强模板匹配变阈值分割

试论优秀思维品质的内在特点和优秀思维能力的实质性要求

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学术前沿 2022年第15期 4-15页

作者：方江山人民日报社

马克思主义哲学非常好地解决了思维与存在的关系问题。本文尝试从认识论、实践论视角对优秀思维品质和优秀思维能力进行研究,深入把握优秀思维品质的内在特点和优秀思维能力的实质性要求。优秀思维品质的内在特点,概括起来说,就是很强... 详细信息

马克思主义哲学非常好地解决了思维与存在的关系问题。本文尝试从认识论、实践论视角对优秀思维品质和优秀思维能力进行研究,深入把握优秀思维品质的内在特点和优秀思维能力的实质性要求。优秀思维品质的内在特点,概括起来说,就是很强的活跃度与很高的成熟度的高度统一、丰富的具体化与严密的系统化的高度统一、饱满的理论深度与充分的实践强度的高度统一。优秀思维能力的实质性要求,概括起来说,就是坚持问题意识、坚持纵横递进、坚持综合分析、坚持目标导向。

关键词：思维与存在认识论实践论优秀思维品质与能力

A Study of the Pion from BLFQ

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IMP & HIRFL Annual Report 2019年第1期 13-14页

作者： Lan jiangshan Chandan Mondal Zhao Hengfei Zhao Xingbo 不详

We study the properties of the pion through the light-front wave function(LFWF)obtained from a basis lightfront quantization(BLFQ)approach[1−4].BLFQ is a nonperturbative approach to quantum field theory based on the H... 详细信息

关键词： Hamiltonian quantum feasible