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Assessment of column aerosol optical properties using ground-based sun-photometer at urban Harbin, Northeast China

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Journal of Environmental Sciences 2018年第12期30卷 50-57页

作者： qixiang chen Yuan Yuan Xing Huang Zhihong He Heping Tan Key Laboratory of Aerospace Thermophysics Ministry of Industry and Information Technology Harbin Institute of Technology College of Metallurgy and Energy North China University of Science and Technology

Aerosol plays a key role in determining radiative balance, regional climate and human *** air pollution over Northeast China in recent years urges more comprehensive studies to figure out the adverse effects caused by excessive aerosols. In this study, column aerosol measurements over urban Harbin, a metropolis located at the highest latitude in Northeast China, during May 2016 to March 2017 were conducted using a CIMEL sun-photometer to analyze local aerosol properties and its variation from different aspects. According to the observations, aerosol optical depth at 440 nm（AOD_（440）） ranges from 0.07 up to 1.54, and the large variability in both AOD_（440） and Angstrom Exponent（AE_（440–870）） indicates the frequent change of aerosol types due of different emission sources. Coarse mode particles dominated Harbin during the studying period because of the long-range transported dust and probably the suspended snow crystals in winter. As the wavelength increases, relatively consistent decrease trends of single scattering albedo（SSA） and asymmetry factor（ASY） were observed in spring, autumn, and winter, indicating the presence of absorbing polluted aerosols. Mixed type（MIX） aerosol dominated the study region with a total percentage of 34%, and biomass burning and urban industry（BB/UI）, clean continental（CC）, and desert dust（DD） aerosols were found to be 31%, 27%, and 8%, respectively. The current work fills up the optical characteristics of aerosols in Harbin, and will contribute to the in-depth understanding of local aerosol variation and regional climate change over Northeast China.

关键词： Sun-photometer Column aerosol property Aerosol type Urban Harbin Northeast China

Precipitation behaviors of X70 acicular ferrite pipeline steel

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Journal of University of Science and Technology Beijing 2006年第6期13卷 523-527页

作者： Hao Yu Yi Sun qixiang chen Haitao Jiang Lihong Zhang Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Jinan Iron ＆ Steel Group Co. Jinan 250101 China

The morphology, structure, and chemical composition of precipitates in the final microstructure of Nb-V-Ti microalloyed X70 acicular ferrite pipeline steel were investigated using transmission electron microscopy （TEM） and energy dispersive X-ray spectroscopy （EDS）. Precipitates observed by TEM can be classified into two groups. The large precipitates are complex compounds that comprise square-shaped TiN precipitate as core with fine Nb-containing precipitate nucleated on pre-existing TiN precipitate as caps on one or more faces at high temperature. In contrast, the fine and spherical Nb carbides and/or carbonitrides precipitate heterogeneously on dislocations and sub-boundaries at low temperature. From the analysis in terms of thermodynamics, EDS and chemical cornposition of the steel, NbC precipitation is considered to be the predominant precipitation behavior in the tested steel under the processing conditions of this research.

关键词： pipeline steel acicular ferrite microstructure carbonitride precipitation behavior thermodynamics

Fengyun-4 Geostationary Satellite-Based Solar Energy Nowcasting System and Its Application in North China

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Advances in Atmospheric Sciences 2022年第8期39卷 1316-1328页

作者： Chunlin HUANG Hongrong SHI Ling GAO Mengqi LIU qixiang chen Disong FU Shu WANG Yuan YUAN Xiang′ao XIA Key Laboratory of Aerospace Thermophysics Ministry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin 150001China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China National Satellite Meteorological Center China Meteorological AdministrationBeijing 100192China Key Laboratory of Atmospheric Sounding Chengdu University of Information TechnologyChengdu 610225China State Key Laboratory of Operation and Control of Renewable Energy&Storage Systems China Electric Power Research Institute(CEPRI)Beijing 100192China Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Surface solar irradiance(SSI)nowcasting(0-3 h)is an effective way to overcome the intermittency of solar energy and to ensure the safe operation of grid-connected solar power *** this study,an SSI estimate and nowcasting system was established using the near-infrared channel of Fengyun-4A(FY-4A)geostationary *** system is composed of two key components:The first is a hybrid SSI estimation method combining a physical clear-sky model and an empirical cloudy-sky *** second component is the SSI nowcasting model,the core of which is the derivation of the cloud motion vector(CMV)using the block-matching *** goal of simultaneous estimation and nowcasting of global horizontal irradiance(GHI)and direct normal irradiance(DNI)is *** system was evaluated under different sky conditions using SSI measurements at Xianghe,a radiation station in the North China *** results show that the accuracy of GHI estimation is higher than that of DNI estimation,with a normalized root-mean-square error(nRMSE)of 22.4%relative to 45.4%.The nRMSE of forecasting GHI and DNI at 30-180 min ahead varied within 25.1%-30.8%and 48.1%-53.4%,*** discrepancy of SSI estimation depends on cloud occurrence frequency and shows a seasonal pattern,being lower in spring-summer and higher in *** FY-4A has great potential in supporting SSI nowcasting,which promotes the development of photovoltaic energy and the reduction of carbon emissions in *** system can be improved further if calibration of the empirical method is improved.

关键词： Fengyun-4A surface solar irradiance estimates and forecasting cloud motion block-matching

The Research of Movement Simulation in Bianzhong Choreography

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微计算机信息 2007年第21期23卷 255-258页

作者： chen qixiang SUN JUNYI chen XIAOWEI SHENG JIANHUI 单位不详

This paper introduces the process of producing movement database on a virtual model for the Bianzhong *** focus-es on analyzing the movement taxonomy and corresponding relationship under the dancing *** study the movement style identifica-tion theory based on the emotion model,present a movement connection method by defining the attributes of characteristically movement units and their related restriction,and give the application framework of the method in Movement Compilation System.

关键词：编钟乐舞动作编辑风格鉴定动作属性关联约束

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***页面间传值方法研究

计算机工程 2006年第8期32卷 113-114,117页

作者：陈启祥左强湖北工业大学计算机学院武汉430068

*** Web Forms提供了很好的事件驱动编程模型,给开发工作带来诸多便利,但是,它也存在一些不足之处,页面间的值传送问题便是一个例子。该文重点探讨了解决这种页面间传值问题的6种方法,实验结果表明,该方法具备较高的效率和精度。

关键词： *** 驱动编程传值

TWO-INPUT PRESETTING TECHNIQUE AND DESIGN OF CMOS FLIP-FLOPS WITH A HIGH RADIX

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Journal of Electronics(China) 1994年第2期11卷 187-192页

作者：吴训威陈其翔 Hangzhou University Hangzhou 310028 Beijing Union University Beijing 100020

By analysing the difficulty of previous flip-flops with a high radix, this paper proposes a logic design scheme with two presetting inputs. The circuit of a quaternary CMOS flip-flop is designed by using the transmission function theory. The result shows that its structure is simpler and its processing speed is higher than that of two binary flip-flops which store the equal information.

关键词： Multivalued logic CMOS Flip-fiop Transmission function theory

基于Rijndael和ECC算法的网络数据安全系统

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计算机工程 2006年第9期32卷 157-158,161页

作者：陈启祥左强邱小军湖北工业大学计算机学院武汉430068

根据某防水墙在应用中面临的网络数据安全实际问题,在优先考虑了安全性的情况下,兼顾了效率、应用环境、运行速度、资源消耗和灵活性后,从密码学角度出发,提出以Rijndael和ECC两种加密算法相结合的数据安全系统。理论分析和实际运行表... 详细信息

根据某防水墙在应用中面临的网络数据安全实际问题,在优先考虑了安全性的情况下,兼顾了效率、应用环境、运行速度、资源消耗和灵活性后,从密码学角度出发,提出以Rijndael和ECC两种加密算法相结合的数据安全系统。理论分析和实际运行表明该系统是一种有效安全的实用方案。在安全产品开发的应用中获得了极大成功,证明了该方案系统能达到预期设计目的。

关键词： Rijndael算法 ECC算法网络数据安全

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德布罗意驻波及Ψ波函数的物理实质

前沿科学 2010年第3期4卷 63-70页

作者：陈其翔北京联合大学自动化学院

本文在平直时空中引导出一个新的引力理论,即物质场理论,使引力容易与电磁场及量子力学相联系。根据物质场理论得出物质场驻波方程及其驻波解。物质场驻波从理论上再现了德布罗意对基本粒子驻波的预言,其相波可作为Ψ波函数的一种新解... 详细信息

本文在平直时空中引导出一个新的引力理论,即物质场理论,使引力容易与电磁场及量子力学相联系。根据物质场理论得出物质场驻波方程及其驻波解。物质场驻波从理论上再现了德布罗意对基本粒子驻波的预言,其相波可作为Ψ波函数的一种新解释。物质场驻波方程的球坐标解,得出物质场驻波不同的振动模式,反映出各种基本粒子的存在方式。

关键词：引力场物质场理论基本粒子驻波 Ψ波函数

美观、实用、适度、环保——我国纸盒包装发展之方略

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印刷杂志 2007年第7期 9-14页

作者：陈麒祥中国包装联合会包装印刷委员会

纸盒（箱）包装因其材质轻,强度高,印刷及后序加工适性好,且绿色环保,便于回收再利用,又属可再生资源,故而在商品包装中被广泛使用。进入新世纪以来,纸盒（箱）包装的消费量,正稳步上升。

关键词：纸盒包装美观实用适度环保