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核电站大气核污染扩散预警技术 被引量:3
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作者 沈越 胡筱敏 +1 位作者 马云峰 陈国平 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2017年第10期1482-1485,1490,共5页
基于环境保护指挥自动化系统C4ISRE,提出了核电站大气核污染扩散预警方法.首先,构建红沿河核电站"海/陆/空/天一体化"仿真环境.其次,根据核污染扩散想定应用气象数据驱动HYSPLIT4.9模型,模拟大气核污染物输送特征,进而推演模... 基于环境保护指挥自动化系统C4ISRE,提出了核电站大气核污染扩散预警方法.首先,构建红沿河核电站"海/陆/空/天一体化"仿真环境.其次,根据核污染扩散想定应用气象数据驱动HYSPLIT4.9模型,模拟大气核污染物输送特征,进而推演模拟各个重点区域的预警应急处置时间.推演结果表明:核污染扩散气团经过71.885 s到达常规岛废液贮存罐厂房;79.306 s扩散至热机修车间和仓库;91.596 s抵达废水处理站和车库;132.267 s扩散至厂界海区边界;655.337 s扩散至烟羽应急区5 km边界;712 s进入黄泥洞村空界;1 240.535 s扩散至烟羽应急区10 km边界;2 527.945 s扩散至长兴岛镇空界;3 468.65 s扩展至烟羽应急区30 km边界. 展开更多
关键词 C4ISRE 电站 大气核污染扩散 海陆空天一体化 HYSPLIT
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基于C4ISRE系统的核电站大气核污染扩散轨迹系统仿真研究
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作者 沈越 胡筱敏 +4 位作者 马云峰 王琦 王廷帅 李强强 石晓飞 《环境科学研究》 EI CAS CSCD 北大核心 2017年第6期835-843,共9页
为了在核污染事故处理时提供精细化预警,以辽宁省某核电站周边部分重要目标(大衣屯、大周屯、红沿河镇、驼山乡、西杨乡、复大线应急撤离线路)为研究对象,将环境保护指挥自动化系统C4ISRE(Command,Control,Communications,Computer,Inte... 为了在核污染事故处理时提供精细化预警,以辽宁省某核电站周边部分重要目标(大衣屯、大周屯、红沿河镇、驼山乡、西杨乡、复大线应急撤离线路)为研究对象,将环境保护指挥自动化系统C4ISRE(Command,Control,Communications,Computer,Intelligence,Surveillance,Reconnaissance,Environmental Impact Assessment)与HYSPLIT 4.9模型相耦合,采用NCEP(美国国家环境预报中心)的FNL全球气象数据对核污染扩散轨迹进行仿真研究.结果表明:自模拟初始时间2014-04-01T00:00:00.00开始,进、出大衣屯边界时间分别为00:06:16.560、00:06:49.000,历时31.340 s;由西向东横穿过大周屯,进、出时间分别为于00:06:16.56到达大衣屯北部边界,于00:06:46.90扩散出大衣屯边界,经过大衣屯区域耗时共计29.00 s;核污染气团于00:15:30.85到达大周屯上空500 m处,由西向东横穿过大周屯,于00:15:46.05离开大周屯上空,过程耗时15.20 s;核污染气团于00:32:14.25经过重要应急撤离线路2(复大线),全程耗时32 min 14.25 s.核污染气团与从2014-04-01T00:00:00.000进入红沿河镇上空500 m区域,于00:24:27.00扩散出,全程历时24 min 27.00 s;进、出驼山乡上空500 m区域的时间分别为00:24:28、00:51:00,历时26 min 32.00 s;进、出西杨乡上空的时间分别为00:51:01、01:05:4.70,历时14 min 37.00 s;重点区域大衣屯和大周屯行政区的预警时间分别为376.56、930.85 s,重点撤离线路2区域预警时间为1 934.25 s. 展开更多
关键词 C4ISRE 大气核污染扩散轨迹 HYSPLIT
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大气核爆炸对平流层臭氧含量影响的模拟
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作者 Ю.А.Израль 张贵银 《气象科技》 北大核心 1992年第3期61-68,共8页
本文探讨了百万吨级大气核爆炸对臭氧天然浓度局地短期变化的影响,其中考虑到了核爆炸火球紫外线和γ射线辐射,核爆炸蘑菇云中的光化学反应以及在其上升过程中和稳定之后的漫射扩散等对大气中臭氧生成的影响。本文对北半球平流层臭氧含... 本文探讨了百万吨级大气核爆炸对臭氧天然浓度局地短期变化的影响,其中考虑到了核爆炸火球紫外线和γ射线辐射,核爆炸蘑菇云中的光化学反应以及在其上升过程中和稳定之后的漫射扩散等对大气中臭氧生成的影响。本文对北半球平流层臭氧含量在核爆炸尘埃和氮氧化物注入情况下的变化进行了估算,其中考虑到了爆炸尘埃对平流层大气的加热因素和大气天然的自洁作用。 展开更多
关键词 大气核 爆炸 平流层 臭氧 含量
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一种定向非采集式气载放射性核素在线测量系统的研制
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作者 王亮 唐传丰 +3 位作者 朱小铰 吕映赋 邓志鹏 余鹏 《四川环境》 2024年第2期111-116,共6页
无论是发生核爆、核事故或核设施正常运行期间,都会向大气中排放放射性核素。为了更加及时、准确、有效地评价气载放射性,根据建立的各核素的照射量率与其活度浓度的数理模型,结合地面伽马射线屏蔽装置,研制了定向非采集式气载放射性核... 无论是发生核爆、核事故或核设施正常运行期间,都会向大气中排放放射性核素。为了更加及时、准确、有效地评价气载放射性,根据建立的各核素的照射量率与其活度浓度的数理模型,结合地面伽马射线屏蔽装置,研制了定向非采集式气载放射性核素在线测量系统,并计算了气载放射性核素40 K的活度浓度。结果表明研制的定向非采集式气载放射性核素在线测量系统能够精确测量大气的放射性核素的活度浓度,并具有方便快捷、测量范围大、响应时间低、能实现在线测量等优点。 展开更多
关键词 大气放射性 在线测量 伽马射线测量 气载放射性
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大气生成宇宙成因核素^(10)Be在中国黄土中的应用研究进展 被引量:2
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作者 孔祥辉 周卫健 +3 位作者 武振坤 杜雅娟 赵国庆 谢兴俊 《地球环境学报》 2016年第3期227-237,共11页
中国黄土^(10)Be研究大体上经历了三个阶段:(1)地球化学行为研究:^(10)Be主要吸附于细颗粒及粘土颗粒,在黄土中保存性好,不会发生明显的化学迁移过程;(2)古气候代用指标应用:^(10)Be在黄土和古土壤层中的浓度变化与代表气候变化的深海... 中国黄土^(10)Be研究大体上经历了三个阶段:(1)地球化学行为研究:^(10)Be主要吸附于细颗粒及粘土颗粒,在黄土中保存性好,不会发生明显的化学迁移过程;(2)古气候代用指标应用:^(10)Be在黄土和古土壤层中的浓度变化与代表气候变化的深海氧同位素曲线变化一致,且可借此进行黄土年代标尺的建立;(3)地球环境示踪研究:示踪地磁场倒转及漂移事件,恢复古地磁场相对强度变化,以及定量重建黄土高原地区古降水变化历史等。由于近年来黄土^(10)Be环境示踪研究取得了可喜的成果,笔者认为有必要从以上三个方面对中国黄土^(10)Be研究历史进行较为系统的梳理回顾,总结当前最新研究进展,展望未来黄土^(10)Be在环境示踪中的研究方向,希望能使读者在短时间内了解中国黄土^(10)Be研究的发展脉络。 展开更多
关键词 大气生成宇宙成因素10Be 地球化学行为 黄土高原 古地磁场强度 古地磁极性倒转与漂移 古降水
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四种拉格朗日粒子浓度计算方法的评估——箱式计数法、高斯核、均匀核和抛物线核 被引量:1
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作者 杨力 王存友 +3 位作者 陈义学 庄舒涵 李新鹏 方晟 《中国环境科学》 EI CAS CSCD 北大核心 2023年第7期3404-3415,共12页
通过对福岛第一核电站事故释放的放射性核素^(137)Cs开展局部尺度的扩散模拟,研究了拉格朗日粒子扩散模型的4种浓度计算方法(箱式计数法、高斯核、均匀核和抛物线核)的有效性.应用气象诊断模型CALMET生成诊断风场,以驱动拉格朗日粒子扩... 通过对福岛第一核电站事故释放的放射性核素^(137)Cs开展局部尺度的扩散模拟,研究了拉格朗日粒子扩散模型的4种浓度计算方法(箱式计数法、高斯核、均匀核和抛物线核)的有效性.应用气象诊断模型CALMET生成诊断风场,以驱动拉格朗日粒子扩散模型LAPMOD,并将所计算的放射性核素^(137)Cs的浓度结果与双葉町和楢叶町监测站的测量值进行对比.结果显示,4种方法成功再现了2个监测站大部分的测量峰值(双葉町平均FAC10:0.57;楢叶町平均FAC10:0.55).箱式计数法、均匀核以及抛物线核结果更接近观测峰值且基本满足统计接受指标,但高斯核结果存在明显低估.浓度分布结果显示,箱式计数法、均匀核以及抛物线核在数值上趋势一致.此外,均匀核以及抛物线核烟羽扩散范围较广,而高斯核的浓度结果在下风向数值衰减迅速. 展开更多
关键词 福岛事故 放射性大气扩散 粒子浓度计算方法 CALMET LAPMOD
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适于反演陆面大气气溶胶光学厚度的物理量 被引量:2
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作者 邵鸿飞 毛节泰 《中国科学技术大学学报》 CAS CSCD 北大核心 1999年第6期684-690,共7页
针对水平均一的晴天大气、朗伯下垫面的特殊条件,在一定理论分析的基础上,利用具有“频率相近、但气体吸收系数相差很大”特征的一对观测频率,构造了一个对地面反照率不敏感,但对气溶胶光学厚度敏感的无量纲物理量.进而借助Low... 针对水平均一的晴天大气、朗伯下垫面的特殊条件,在一定理论分析的基础上,利用具有“频率相近、但气体吸收系数相差很大”特征的一对观测频率,构造了一个对地面反照率不敏感,但对气溶胶光学厚度敏感的无量纲物理量.进而借助LowtranDisort 耦合模式的数值实验,确定了观测的最佳方位,并比较了最佳观测方位下对地面反照率和气溶胶光学厚度的不同敏感性. 展开更多
关键词 地面反照率 大气 气溶胶 大气凝结 光学特性
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大气主要污染物与细菌气溶胶在冰核核化过程中的作用:对液滴冻结温度的影响 被引量:2
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作者 王亚玲 杜睿 +1 位作者 梁宗敏 李梓铭 《中国科学:地球科学》 CSCD 北大核心 2012年第5期692-700,共9页
冰核细菌气溶胶作为有效云凝结核与冰核可能在大气物理与化学过程和气象过程中起重要作用,其核化特性也受大气和云中气溶胶的物理、化学性质的影响.本研究依据Vali均匀液滴冻结实验的原理,采用改进的液滴冻结仪分别测试了大气典型污染物... 冰核细菌气溶胶作为有效云凝结核与冰核可能在大气物理与化学过程和气象过程中起重要作用,其核化特性也受大气和云中气溶胶的物理、化学性质的影响.本研究依据Vali均匀液滴冻结实验的原理,采用改进的液滴冻结仪分别测试了大气典型污染物(硫酸铵;一元羧酸(MCA):甲酸和乙酸钠;二元羧酸(DCA):乙二酸和丙二酸)与不同浓度的细菌菌液(冰核活性细菌Pseudominas syringae pv.lachrymans(PS))和非冰核细菌P.syringae pv.panici(PS0))的冻结温度.结果显示:不同浓度的MCA/DCA(50,75,100μmol L-1)和硫酸铵(100,200,300,400μmol L-1)溶液液滴(10μL)的平均冻结温度范围在-17.0~-20.0℃,相比超纯水液滴的冻结温度(-20.6±1.6)℃,典型大气污染物的加入并未显著提升超纯水液滴的冻结温度,而且污染物溶液浓度的改变对冻结温度没有表现出明显的规律性.冰核细菌PS和非冰核细菌菌液PS0与大气主要污染物(乙酸钠、乙二酸和硫酸铵)混合液的液滴冻结温度测试结果发现:这些污染物质不同程度降低了细菌PS与PS0菌液的冻结温度,即使PS在较低浓度下也可促进大气主要污染物乙酸钠的冻结核活性,提高其冻结温度;当浓度增至106cells mL-1时,则能显著改变污染物质的冻结核活性;但未发现PS0有此特性.复合污染物溶液浓度接近当前污染大气水平时,对冰核细菌PS和较高浓度级数(106cells mL-1)的PS0的冻结核活性都显示出了促进效应,表明在当前大气环境条件下,细菌气溶胶确实有可能影响降水过程和气候变化.冰核活性细菌与非活性冰核细菌混合后,只有当冰核细菌浓度级数达到106cells mL-1时,在混合液中才可表现出高效冰核活性.冰核细菌的浓度值是影响其活性的重要因素,使其在溶液中显示高效冰核活性的菌浓度阈值级数是106cells mL-1;本研究结果对于人工影响天气过程中,人工冰核的选择和配比方法优化方面具有一定的科学意义. 展开更多
关键词 细菌气溶胶 活性细菌 大气主要污染物 冻结温度
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Environmental Low Energy Gamma Rays Measurements in Brazilian Tropics Region During 2016
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作者 Inaicio Malmonge Martin Anatoli Alexandrovitch Goussev +5 位作者 Douglas Carlos Vilela Marcelo Pego Gomes Mauro Angelo Alves Alessandro de Abreu Matheus Carlos Silva Rodrigo Rezende Femandez de Carvalho 《Journal of Environmental Science and Engineering(A)》 2016年第11期559-565,共7页
Low energy gamma radiation (0.2-10.0) MeV near the Earth's surface has several origins. Primary and secondary cosmic radiations with interactions of very high energy protons (〉 1 GeV) in terrestrial atmosphere a... Low energy gamma radiation (0.2-10.0) MeV near the Earth's surface has several origins. Primary and secondary cosmic radiations with interactions of very high energy protons (〉 1 GeV) in terrestrial atmosphere are the main sources. The second most important source near the surface of the Earth and in the tropical and equatorial regions is the radon gas (Rn-222) that decays in alpha particles and gamma rays in this energy range. Also the telluric radionuclides 238U, 235U, 40K and 232Th in decays produce gamma radiation with different intensities at different locations on the surface of the Earth. Other sources less present are electrical discharges (lightning strikes) and man-made radioactive sources for medical, dental and industrial applications. In this work, it is shown that measurements of these components during all year 2016 are carried out at the ITA (Technological Institute of Aeronautics) campus in Sao Jose dos Campos, SP, Brazil and their possible correlations with atmospheric phenomena. 展开更多
关键词 Gamma radiation atmospheric phenomena electric discharges radon gas.
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Technique Development and Application——Construction of a Beowulf Cluster for Parallel Computing
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作者 FENG Kun DONG Jiaqi ZHANG Jinhua 《Southwestern Institute of Physics Annual Report》 2004年第1期138-141,共4页
The large-scale computations are often performed in science and engineering areas such as numerical weather forecasting, astrophysics, energy resources exploration, nuclear weapon design, and plasma fusion research et... The large-scale computations are often performed in science and engineering areas such as numerical weather forecasting, astrophysics, energy resources exploration, nuclear weapon design, and plasma fusion research etc. Many applications in these areas need super computing power. The traditional mode of sequential processing cannot meet the demands of those computations, thus, parallel processing(PP) is the main way of high performance computing (HPC) now. 展开更多
关键词 Parallel Computing Beowulf Cluster MPICH
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大气放射性气溶胶连续监测大流量空气采样 被引量:5
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作者 王文海 孟庆华 +8 位作者 娄云 李慧娟 万玲 张泓 翟曙光 彭建亮 俞军 冯泽臣 朱维杰 《中国辐射卫生》 2010年第4期484-486,共3页
目的提出大气放射性气溶胶连续监测大流量空气采样中所遇问题(如滤膜堵塞、滤膜吸水及空气中颗粒物对探测效率的影响)的解决办法。方法通过对连续监测取得的数据进行分析,通过实验模拟滤膜堵塞情况,并通过实际工作验证。结果获得具有连... 目的提出大气放射性气溶胶连续监测大流量空气采样中所遇问题(如滤膜堵塞、滤膜吸水及空气中颗粒物对探测效率的影响)的解决办法。方法通过对连续监测取得的数据进行分析,通过实验模拟滤膜堵塞情况,并通过实际工作验证。结果获得具有连续代表性的样品,并且获取到有效监测结果数据的天数占全年天数的比例逐年上升,2003~2006年分别为71%,86%,94%,96%。结论通过采取综合手段,能够减小不利气候因素对采样连续代表性的影响,获得理想的数据有效率。应通过对探测效率进行修正而减小空气中颗粒物含量对探测效率的影响。 展开更多
关键词 大流量空气采样器 大气中放射性 连续监测 采样
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灰尘引起高功率激光系统放大介质的表面破坏 被引量:4
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作者 孟绍贤 《激光与光电子学进展》 CSCD 2000年第8期28-31,共4页
详细地分析了灰尘的形成过程 ,计算了灰尘沉积与温度和灰尘尺寸关系 ,提出了减少灰尘的方法。
关键词 灰尘 大气凝结 大功率激光系统 放大介质
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The comparison of ensemble or deterministic dispersion modeling on global dispersion during Fukushima Dai-ichi nuclear accident 被引量:3
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作者 SHENG Li SONG ZhenXin +4 位作者 HU JiangKai Lü Kai TONG Hua LI Bing QIAO QingDang 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第3期356-370,共15页
Ensemble forcasting,originally developed for weather prediction,is lately being extended to atmospheric dispersion applications,which is a new,effective methodology for improving the atmospheric dispersion numerical m... Ensemble forcasting,originally developed for weather prediction,is lately being extended to atmospheric dispersion applications,which is a new,effective methodology for improving the atmospheric dispersion numerical modeling.In March 2011,due to the massive 9.0 earthquakes and ensuing tsunami that struck off the northern coast of the island of Honshu,the Fukushima Nuclear Plant I had the substantial leak of radioactive materials into surrounding environment and atmosphere.To aim at the global dispersion modeling of atmospheric radionuclides from Fukushima Nuclear Accident,this paper presents two approaches of atmospheric dispersion forecasting:ensemble dispersion modeling(EDM) and deterministic dispersion modeling(DDM),conducts the globally dispersion modeling cases for Fukushima nuclear accident,and analyzes and evaluates the simulation results using observation data.In this paper,EDM includes three different perturbation methods:meteorological perturbation method,turbulence perturbation method,and physical parameterization ensemble forecasting method.The simulation results show that the trajectories from EDM have a better performance,which is in better agreement with the atmospheric circulation and observation data; the spread from DDM is slower and not as far as EDM.Additionally,the results from EDM display a better performance in the modeling of transport from Japan to China East Sea on April 4.The reasons for these results are:the techniques of MET and TUR are performed by adding perturbations on mean wind and turbulent velocity,respectively; the various different flow fields will result in far spreading in horizontal and the simulation results closer to observation; PHY is performed by using different diffusion physical parameterizations and produces the perturbations on vertical wind,which results the spreading in smaller range and discontinuous in horizontal.Finally,the comparative analysis between modeling results and observation data shows that all cases results are in good agreement with trends of observed radionuclides surface concentration; however,the modeling surface concentration is smaller than observation,especially in DDM and PHY.Furthermore,the EDM results show that MET and TUR are of more evolutionary advantage than PHY in modeling of average and maximum concentration.Therefore,this study can serve as a reference to atmospheric dispersion and environmental emergency response(EER). 展开更多
关键词 ensemble dispersion modeling deterministic dispersion modeling atmospheric dispersion Fukushima nuclear accident
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Hαcounterparts of X-ray bright points in the solar atmosphere
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作者 ZHANG Ping FANG Cheng ZHANG QingMin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第5期907-914,共8页
X-ray bright points (XBPs) are small-scale brightenings in the solar corona. Their counterparts in the lower atmosphere, how- ever, are poorly investigated. In this paper, we study the counterparts of XBPs in the up... X-ray bright points (XBPs) are small-scale brightenings in the solar corona. Their counterparts in the lower atmosphere, how- ever, are poorly investigated. In this paper, we study the counterparts of XBPs in the upper chromosphere where the Hot line center is formed. The XBPs were observed by the X-ray Telescope (XRT) aboard the Hinode spacecraft during the observing plan (HOP0124) in August 2009, coordinated with the Solar Magnetic Activity Research Telescope (SMART) in the Kwasan and Hida Observatory, Kyoto University. It is found that there are 77 Hot brightenings in the same field of view of XRT, and among 57 XBPs, 29 have counterparts in the Hot channel. We found three types of relationship: Types a, b and c, correspond- ing to XBPs appearing first, Hot brightenings occurring first and no respective correspondence between them. Most of the strong XBPs belong to Type a. The Hot counterparts generally have double-kernel structures associated with magnetic bipoles and are cospatial with the footpoints of the XBP loops. The average lag time is -3 minutes. This implies that for Type a the heating, presumably through magnetic reconnection, occurs first in the solar upper atmosphere and then goes downwards along the small-scale magnetic loops that comprise the XBPs. In this case, the thermal conduction plays a dominant role over the non-thermal heating. Only a few events belong to Type b, which could happen when magnetic reconnection occurs in the chromosphere and produces an upward jet which heats the upper atmosphere and causes the XBP. About half of the XBPs belong to Type c. Generally they have weak emission in SXR. About 62% Hot brightenings have no corresponding XBPs. Most of them are weak and have single structures. 展开更多
关键词 solar activity bright points small-scale brightenings
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A CLASSIFICATION INDICES-BASED MODEL FOR NET PRIMARY PRODUCTIVITY (NPP) AND POTENTIAL PRODUCTIVITY OF VEGETATION IN CHINA 被引量:6
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作者 HUILONG BIN JUN ZHAO +1 位作者 TIANGANG LIANG ZHENQING LI 《International Journal of Biomathematics》 2012年第3期145-167,共23页
Net Primary Productivity (NPP) is an important parameter, which is closely connected with global climate change, the global carbon balance and cycle. The study of climate- vegetation interaction is the basis for res... Net Primary Productivity (NPP) is an important parameter, which is closely connected with global climate change, the global carbon balance and cycle. The study of climate- vegetation interaction is the basis for research on the responses of terrestrial ecosystemto global change and mainly comprises two important components: climate vegetation classification and the NPP of the natural vegetation. Comparing NPP estimated from the classification indices-based model with NPP derived from measurements at 3767 sites in China indicated that the classification indices-based model was capable of estimating large scale NPP. Annual cumulative temperature above 0~C and a moisture index, two main factors affecting NPP, were spatially plotted with the ArcGIS grid tool based on measured data in 2348 meteorological stations from 1961 to 2006. The distribution of NPP for potential vegetation classes under present climate conditions was simulated by the classification indices-based model. The model estimated the total NPP of potential terrestrial vegetation of China to fluctuate between 1.93 and 4.54 Pg C year-1. It pro- vides a reliable means for scaling-up from site to regional scales, and the findings could potentially favor China's position in reducing global warming gases as outlined in the Kyoto Protocol in order to fulfill China's commitment of reducing greenhouse gases. 展开更多
关键词 Net primary productivity (NPP) climate-vegetation interaction IntegratedOrderly Classification System (IOCS) classification indices-based model potential productivity of natural vegetation.
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The effects of giant cloud condensation nuclei on the structure of precipitation in hailstorm clouds
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作者 YANG HuiLing XIAO Hui HONG YanChao 《Science China Earth Sciences》 SCIE EI CAS 2012年第1期126-142,共17页
The Regional Atmospheric Modeling System (RAMS) has been used to investigate the effects of varied giant cloud condensation nuclei (GCCN) concentrations on precipitation characteristics of the spring hailstorms in a s... The Regional Atmospheric Modeling System (RAMS) has been used to investigate the effects of varied giant cloud condensation nuclei (GCCN) concentrations on precipitation characteristics of the spring hailstorms in a semi-arid region. The simulation result shows that this variation has significant effects on the storm microphysical processes as well as on the surface precipitation. The coverage of hail and hail mixing ratio maxima in cloud increases with greater GCCN concentrations. The accumulation zone structure benefits the growth of hail particles. Higher GCCN concentrations lead to more supercooled rain water and cloud water available for freezing. This simulation also shows that increasing GCCN concentrations may produce more rainfall on the surface but less hail precipitation, and the total accumulated precipitation increases while the ice phase precipitation decreases. This effect is stronger in polluted air than in clean air. The surface flow field changes with different GCCN concentrations. The identification index of spring hailstorm is different from that of summer hailstorm with a different aerosol background. 展开更多
关键词 AEROSOL giant cloud condensation nuclei (GCCN) micro-physics HAILSTORM PRECIPITATION
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UAV remote sensing atmospheric degradation image restoration based on multiple scattering APSF estimation
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作者 仇翔 戴明 尹传历 《Optoelectronics Letters》 EI 2017年第5期386-391,共6页
Unmanned aerial vehicle(UAV) remote imaging is affected by the bad weather, and the obtained images have the disadvantages of low contrast, complex texture and blurring. In this paper, we propose a blind deconvolution... Unmanned aerial vehicle(UAV) remote imaging is affected by the bad weather, and the obtained images have the disadvantages of low contrast, complex texture and blurring. In this paper, we propose a blind deconvolution model based on multiple scattering atmosphere point spread function(APSF) estimation to recovery the remote sensing image. According to Narasimhan analytical theory, a new multiple scattering restoration model is established based on the improved dichromatic model. Then using the L0 norm sparse priors of gradient and dark channel to estimate APSF blur kernel, the fast Fourier transform is used to recover the original clear image by Wiener filtering. By comparing with other state-of-the-art methods, the proposed method can correctly estimate blur kernel, effectively remove the atmospheric degradation phenomena, preserve image detail information and increase the quality evaluation indexes. 展开更多
关键词 CONVOLUTION Fast Fourier transforms Image reconstruction Multiple scattering Optical transfer function RESTORATION Signal receivers Unmanned aerial vehicles (UAV)
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