期刊文献+
共找到21篇文章
< 1 2 >
每页显示 20 50 100
Augmentation of PM_(1.0) measurements based on machine learning model and environmental factors
1
作者 Hyemin Hwang Chang Hyeok Kim +3 位作者 Jong-Sung Park Sechan Park Jong Bum Kim Jae Young Lee 《Journal of Environmental Sciences》 2025年第10期91-101,共11页
PM_(1.0),particulate matter with an aerodynamic diameter smaller than 1.0μm,can adversely affect human health.However,fewer stations are capable of measuring PM_(1.0) concentrations than PM2.5 and PM10 concentrations... PM_(1.0),particulate matter with an aerodynamic diameter smaller than 1.0μm,can adversely affect human health.However,fewer stations are capable of measuring PM_(1.0) concentrations than PM2.5 and PM10 concentrations in real time(i.e.,only 9 locations for PM_(1.0) vs.623 locations for PM2.5 or PM10)in South Korea,making it impossible to conduct a nationwide health risk analysis of PM_(1.0).Thus,this study aimed to develop a PM_(1.0) prediction model using a random forest algorithm based on PM_(1.0) data from the nine measurement stations and various environmental input factors.Cross validation,in which the model was trained in eight stations and tested in the remaining station,achieved an average R^(2) of 0.913.The high R^(2) value achieved undermutually exclusive training and test locations in the cross validation can be ascribed to the fact that all the locations had similar relationships between PM_(1.0) and the input factors,which were captured by our model.Moreover,results of feature importance analysis showed that PM2.5 and PM10 concentrations were the two most important input features in predicting PM_(1.0) concentration.Finally,the model was used to estimate the PM_(1.0) concentrations in 623 locations,where input factors such as PM2.5 and PM10 can be obtained.Based on the augmented profile,we identified Seoul and Ansan to be PM_(1.0) concentration hotspots.These regions are large cities or the center of anthropogenic and industrial activities.The proposed model and the augmented PM_(1.0) profiles can be used for large epidemiological studies to understand the health impacts of PM_(1.0). 展开更多
关键词 Particulate matter Random forest Input factor PM_(1.0)prediction model Cross validation Feature importance analysis
原文传递
Prediction of the Asian-Australian Monsoon Interannual Variations with the Grid-Point Atmospheric Model of IAP LASG(GAMIL) 被引量:10
2
作者 吴志伟 李建平 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2008年第3期387-394,共8页
Seasonal prediction of Asian-Australian monsoon (A-AM) precipitation is one of the most important and challenging tasks in climate prediction. In this paper, we evaluate the performance of Grid Atmospheric Model of ... Seasonal prediction of Asian-Australian monsoon (A-AM) precipitation is one of the most important and challenging tasks in climate prediction. In this paper, we evaluate the performance of Grid Atmospheric Model of IAP LASG (GAMIL) on retrospective prediction of the A-AM interannual variation (IAV), and determine to what extent GAMIL can capture the two major observed modes of A-AM rainfall IAV for the period 1979-2003. The first mode is associated with the turnabout of warming (cooling) in the Nifio 3.4 region, whereas the second mode leads the warming/cooling by about one year, signaling precursory conditions for ENSO. We show that the GAMIL one-month lead prediction of the seasonal precipitation anomalies is primarily able to capture major features of the two observed leading modes of the IAV, with the first mode better predicted than the second. It also depicts the relationship between the first mode and ENSO rather well. On the other hand, the GAMIL has deficiencies in capturing the relationship between the second mode and ENSO. We conclude: (1) successful reproduction of the E1 Nifio-excited monsoon-ocean interaction and E1 Nifio forcing may be critical for the seasonal prediction of the A-AM rainfall IAV with the GAMIL; (2) more efforts are needed to improve the simulation not only in the Nifio 3.4 region but also in the joining area of Asia and the Indian-Pacific Ocean; (3) the selection of a one-tier system may improve the ultimate prediction of the A-AM rainfall IAV. These results offer some references for improvement of the GAMIL and associated seasonal prediction skill. 展开更多
关键词 Asian-Australian monsoon interannual variation ENSO atmospheric general circulation model GAMIL
在线阅读 下载PDF
Performance of a Reconfigured Atmospheric General Circulation Model at Low Resolution 被引量:17
3
作者 闻新宇 周天军 +3 位作者 王绍武 王斌 万慧 李建 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第4期712-728,共17页
Paleoclimate simulations usually require model runs over a very long time. The fast integration version of a state-of-the-art general circulation model (GCM), which shares the same physical and dynamical processes b... Paleoclimate simulations usually require model runs over a very long time. The fast integration version of a state-of-the-art general circulation model (GCM), which shares the same physical and dynamical processes but with reduced horizontal resolution and increased time step, is usually developed. In this study, we configure a fast version of an atmospheric GCM (AGCM), the Grid Atmospheric Model of IAP/LASG (Institute of Atmospheric Physics/State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics), at low resolution (GAMIL-L, hereafter), and compare the simulation results with the NCEP/NCAR reanalysis and other data to examine its performance. GAMIL-L, which is derived from the original GAMIL, is a finite difference AGCM with 72 × 40 grids in longitude and latitude and 26 vertical levels. To validate the simulated climatology and variability, two runs were achieved. One was a 60-year control run with fixed climatological monthly sea surface temperature (SST) forcing, and the other was a 50-yr (1950-2000) integration with observational time-varying monthly SST forcing. Comparisons between these two cases and the reanalysis, including intra-seasonal and inter-annual variability are also presented. In addition, the differences between GAMIL-L and the original version of GAMIL are also investigated.The results show that GAMIL-L can capture most of the large-scale dynamical features of the atmosphere, especially in the tropics and mid latitudes, although a few deficiencies exist, such as the underestimated Hadley cell and thereby the weak strength of the Asia summer monsoon. However, the simulated mean states over high latitudes, especially over the polar regions, are not acceptable. Apart from dynamics, the thermodynamic features mainly depend upon the physical parameterization schemes. Since the physical package of GAMIL-L is exactly the same as the original high-resolution version of GAMIL, in which the NCAR Community Atmosphere Model (CAM2) physical package was used, there are only small differences between them in the precipitation and temperature fields. Because our goal is to develop a fast-running AGCM and employ it in the coupled climate system model of IAP/LASG for paleoclimate studies such as ENSO and Australia-Asia monsoon, particular attention has been paid to the model performances in the tropics. More model validations, such as those ran for the Southern Oscillation and South Asia monsoon, indicate that GAMIL-L is reasonably competent and valuable in this regard. 展开更多
关键词 GCM GAMIL-L ATMOSPHERE model validation
在线阅读 下载PDF
Aerosol Indirect Effects on Warm Clouds in the Grid-Point Atmospheric Model of IAP LASG(GAMIL) 被引量:7
4
作者 Shi Xiang-Jun Wang Bin +3 位作者 Liu Xiao-Hong Wang Ming-Huai Li Li-Juan Dong Li 《Atmospheric and Oceanic Science Letters》 2010年第4期237-241,共5页
Aerosol indirect effects on warm clouds are estimated in the Grid-point Atmospheric Model of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmosphe... Aerosol indirect effects on warm clouds are estimated in the Grid-point Atmospheric Model of the State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics(IAP LASG)(GAMIL) with a new two-moment cloud microphysics scheme using two different physically-based aerosol activation parameterizations:Abdul-Razzak and Ghan,and Nenes and Seinfeld.The annual global mean changes in shortwave cloud forcing from preindustrial times to present day(a measure of the aerosol indirect effects) estimated from these two parameterizations are remarkably similar:0.76 W m?2 with the Abdul-Razzak and Ghan parameterization,and 0.78 W m?2 with the Nenes and Seinfeld parameterization.Physically-based parameterizations can provide robust representations of aerosol effects on droplet nucleation,meaning that aerosol activation is no longer the most uncertain factor in modeling aerosol indirect effects. 展开更多
关键词 aerosol indirect effect droplet nucleation atmospheric model GAMIL
在线阅读 下载PDF
An Assessment of MJO and Tropical Waves Simulated by Different Versions of the GAMIL Model 被引量:3
5
作者 MAO Jiang-Yu LI Li-Juan 《Atmospheric and Oceanic Science Letters》 2012年第1期26-31,共6页
Simulated outgoing longwave radiation (OLR) outputs by two versions of the grid-point atmospheric general circulation model (GAMIL) were analyzed to assess the influences of improvements in cloud microphysics and ... Simulated outgoing longwave radiation (OLR) outputs by two versions of the grid-point atmospheric general circulation model (GAMIL) were analyzed to assess the influences of improvements in cloud microphysics and convective parameterization schemes on the simulation of the Madden-Julian oscillation (MJO) and other tropical waves. The wavenumber-frequency spectral analysis was applied to isolate dominant modes of convectively coupled equatorial waves, including the M30, Kelvin, equatorial Rossby (ER), mixed Rossby-gravity (MRG), and inertio-gravity (1G) waves. The performances of different versions of the GAMIL model (version 1.0 (GAMIL1.0) and version 2.0 (GAMIL2.0)) were evalu- ated by comparing the power spectrum distributions of these waves among GAMIL 1.0, GAMIL2.0, and observational data. GAMIL1.0 shows a weak MJO signal, with the maximum variability occurring separately at wavenumbers 1 and 4 rather than being concentrated on wavenumbers 1-3, suggesting that GAMILI.0 could not effectively capture the intraseasonal variability. However, GAMIL2.0 is able to effectively reproduce both the symmetric and anti-symmetric waves, and the significant spectra of the MJO, Kelvin, and MRG waves are in agreement with observational data, indicating that the ability of GAMIL2.0 to simulate the MJO and other tropical waves is enhanced by improving the cloud microphysics and convective parameterization schemes and implying that such improvements are crucial to further improving this model's performance. 展开更多
关键词 GAMIL model MJO tropical waves
在线阅读 下载PDF
Modeling study on the roles of the deposition and transport of PM_(2.5) in air quality changes over central-eastern China
6
作者 Lei Zhang Jianjun He +11 位作者 Sunling Gong Xiaomei Guo Tianliang Zhao Huizheng Che Hong Wang Chunhong Zhou Jingyue Mo Ke Gui Yu Zheng Lei Li Junting Zhong Xiaoye Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第1期535-544,共10页
The role of PM_(2.5)(particles with aerodynamic diameters≤_(2.5)μm)deposition in air quality changes over China remains unclear.By using the three-year(2013,2015,and 2017)simulation results of the WRF/CUACE v1.0 mod... The role of PM_(2.5)(particles with aerodynamic diameters≤_(2.5)μm)deposition in air quality changes over China remains unclear.By using the three-year(2013,2015,and 2017)simulation results of the WRF/CUACE v1.0 model from a previous work(Zhang et al.,2021),a non-linear relationship between the deposition of PM_(2.5)and anthropogenic emissions over central-eastern China in cold seasons as well as in different life stages of haze events was unraveled.PM_(2.5)deposition is spatially distributed differently from PM_(2.5)concentrations and anthropogenic emissions over China.The North China Plain(NCP)is typically characterized by higher anthropogenic emissions compared to southern China,such as the middlelow reaches of Yangtze River(MLYR),which includes parts of the Yangtze River Delta and the Midwest.However,PM_(2.5)deposition in the NCP is significantly lower than that in the MLYR region,suggesting that in addition to meteorology and emissions,lower deposition is another important factor in the increase in haze levels.Regional transport of pollution in central-eastern China acts as a moderator of pollution levels in different regions,for example by bringing pollution from the NCP to the MLYR region in cold seasons.It was found that in typical haze events the deposition flux of PM_(2.5)during the removal stages is substantially higher than that in accumulation stages,with most of the PM_(2.5)being transported southward and deposited to the MLYR and Sichuan Basin region,corresponding to a latitude range of about 24°N-31°N. 展开更多
关键词 PM_(2.5) DEPOSITION Regional transport China WRF/CUACE v1.0 model
原文传递
GAMIL模式海气湍流通量参数化方案的改进及其对大气环流年际变率模拟效果的影响 被引量:6
7
作者 李忠贤 周天军 +2 位作者 孙照渤 陈海山 倪东鸿 《大气科学》 CSCD 北大核心 2011年第2期311-325,共15页
通过引入中尺度对流运动对海表湍流通量的贡献,改进了大气环流模式GAMIL1.0的海气湍流通量参数化方案。利用1979年1月至2000年12月的观测海温资料驱动GAMIL1.0模式,研究了海气湍流通量参数化改进对大气环流年际变化模拟效果的影响。结... 通过引入中尺度对流运动对海表湍流通量的贡献,改进了大气环流模式GAMIL1.0的海气湍流通量参数化方案。利用1979年1月至2000年12月的观测海温资料驱动GAMIL1.0模式,研究了海气湍流通量参数化改进对大气环流年际变化模拟效果的影响。结果表明:采用改进的海气湍流通量参数化方案,模拟的热带海表湍流热通量得到增强,模式对热带降水年际变化的模拟能力得到明显提高,凝结潜热对大气的加热作用更趋合理,模式对冬季(DJF)北太平洋地区和夏季(JJA)南太平洋中纬度地区大气环流年际变化的模拟能力有显著提高,可以更好地模拟出冬季南方涛动、北太平洋涛动的年际变化和空间分布特征,特别是显著地改善了此前GAMIL1.0模式存在的模拟的南方涛动强度偏弱的问题。 展开更多
关键词 gamil1.0模式 海气湍流通量参数化 数值模拟
在线阅读 下载PDF
利用海气耦合模式模拟印度尼西亚贯穿流 被引量:4
8
作者 李志强 俞永强 王谦谦 《大气科学》 CSCD 北大核心 2005年第5期697-708,共12页
利用中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室(LASG)发展的全球耦合气候系统模式(FGCM-1·0)100年数值模拟结果,分析了模式模拟的印度尼西亚贯穿流(ITF)的平均态、季节变化和年际变化,并且利用这些... 利用中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室(LASG)发展的全球耦合气候系统模式(FGCM-1·0)100年数值模拟结果,分析了模式模拟的印度尼西亚贯穿流(ITF)的平均态、季节变化和年际变化,并且利用这些资料对ITF季节变化和年际变化的成因做了初步分析。模式模拟的ITF平均态、季节变化和年际变化同已有的观测结果相比是合理的,经作者分析认为ITF的季节变化主要是因为印度尼西亚海域地处亚澳季风区,海流对于季风的响应使得ITF发生季节变化;ITF的年际变化主要是因为热带环流的年际变化及其所导致的洋流调整造成的,太平洋和印度洋都有影响。 展开更多
关键词 印度尼西亚贯穿流(ITF) 全球耦合气候系统模式(FGCM-1.0) 热带太平洋
在线阅读 下载PDF
创新2.0:升级我们的图书馆服务 被引量:5
9
作者 张峥嵘 《图书与情报》 CSSCI 北大核心 2011年第2期69-71,80,共4页
创新2.0是一种适应知识社会、用户广泛参与的创新形态,是技术进步与应用创新共同演进的社会产物,具有"用户体验是核心"、"用户创新是源泉""用户满意是标准"等理念。创新2.0的典范实践是Living Lab模式、F... 创新2.0是一种适应知识社会、用户广泛参与的创新形态,是技术进步与应用创新共同演进的社会产物,具有"用户体验是核心"、"用户创新是源泉""用户满意是标准"等理念。创新2.0的典范实践是Living Lab模式、Fab Lab模式和AIP模式,其大众创新、共同创新、开放创新等特点可为图书馆服务提供很好的借鉴,构建面向知识社会的图书馆创新2.0服务模式,提升我们的图书馆服务。 展开更多
关键词 创新1.0 创新2.0 创新模式 图书馆服务
在线阅读 下载PDF
小型猪腹壁拉链模型制备效果评价指标体系的建立 被引量:3
10
作者 汤球 余琛琳 崔淑芳 《实验动物与比较医学》 CAS 2011年第3期178-182,共5页
目的建立小型猪腹壁拉链模型制备效果评价指标体系。方法通过文献调研与专家咨询,初步收集评价小型猪腹壁拉链模型制备效果的调研指标,利用德尔菲法和层次分析法,结合专家咨询意见,进一步确定指标及指标权重值,运用人类疾病动物模... 目的建立小型猪腹壁拉链模型制备效果评价指标体系。方法通过文献调研与专家咨询,初步收集评价小型猪腹壁拉链模型制备效果的调研指标,利用德尔菲法和层次分析法,结合专家咨询意见,进一步确定指标及指标权重值,运用人类疾病动物模型评价指标体系软件EISAMHD.中央人民政府 1.0 (The Evaluation Index System Of Animal Model Of Human Diseases, EISAMHD),建立小型猪腹壁拉链模型制备效果综合评价指标体系。结果通过实证,确认该评价体系良好。结论本研究建立的评价指标体系清晰、简便,利于科研人员使用。 展开更多
关键词 小型猪 腹壁拉链模型 评价指标与指标权重 EISAMHD.中央人民政府 1.0评价指标体系
暂未订购
关于Library x.0理论的演变推理与模型构建 被引量:1
11
作者 路茂林 《情报科学》 CSSCI 北大核心 2011年第5期672-675,共4页
通过对从Library 1.0到Library 2.0、Library x.0的演变过程,提出了图书馆球行关系模型,并在此基础上通过空间拓展模型对Library 1.0到Library x.0的理论作了演变推理,构建出Library 2.0理论的未来发展趋势--Library x.0,并提出了Librar... 通过对从Library 1.0到Library 2.0、Library x.0的演变过程,提出了图书馆球行关系模型,并在此基础上通过空间拓展模型对Library 1.0到Library x.0的理论作了演变推理,构建出Library 2.0理论的未来发展趋势--Library x.0,并提出了Library x.0的涵义,为Library 2.0理论的延续作了启发性的研究。 展开更多
关键词 LIBRARY 1.0 LIBRARY 2.0 LIBRARY x.0 球形关系模型 空间拓展模型
原文传递
热带大气对流垂直结构与降水模拟偏差的关系:基于GAMIL3模式的分析 被引量:2
12
作者 任子坤 周天军 +3 位作者 郭准 陈晓龙 李立娟 吴波 《大气科学》 CSCD 北大核心 2023年第2期239-258,共20页
针对LASG/IAP发展的大气环流模式GAMIL(Grid-point Atmospheric Model of IAP LASG)的两个版本GAMIL2(G2)和GAMIL3(G3),评估了其对热带降水气候态以及对流垂直结构的模拟能力,在此基础上探究了新版本模式降水模拟改进的原因以及热带对... 针对LASG/IAP发展的大气环流模式GAMIL(Grid-point Atmospheric Model of IAP LASG)的两个版本GAMIL2(G2)和GAMIL3(G3),评估了其对热带降水气候态以及对流垂直结构的模拟能力,在此基础上探究了新版本模式降水模拟改进的原因以及热带对流垂直结构与降水模拟偏差的关系。两个版本的GAMIL模式都较好地捕捉到了热带降水的主要特征,且G3的模拟结果整体优于G2。新版本的主要改进在于显著减小了热带西北太平洋正降水偏差。水汽收支诊断显示,模式降水偏差主要来源于蒸发项和水汽垂直平流动力项,而后者的偏差则来自于对流强度和对流垂直结构的共同作用。对流垂直结构偏差主要存在于赤道印度洋与赤道大西洋区域,表现为大气低层辐合分量偏小,对流卷出层高度偏高;在热带西北太平洋与赤道东太平洋区域,模式较好地还原了典型的“头重型”和“脚重型”对流垂直结构,但依然存在有整体性的对流偏深。湿静力能(MSE)收支显示,热带西北太平洋区域过量的净能量通量是模式垂直运动偏差的主要来源。而对流垂直结构偏深造成的总湿稳定度(Gross Moist Stability,简称GMS)偏大,在一定程度上抵消了模式中的净能量通量偏差,抑制了模拟的对流强度。诊断结果显示,G3中热带西北太平洋区域的降水改善主要源于对流强度正偏差的减小。G3中对流阈值和层云阈值的下调,使得对流发生频率增加,从而抑制了过大的对流强度。热带对流垂直结构与降水偏差有着紧密且多样的联系,在未来模式发展中应当予以重视。 展开更多
关键词 GAMIL模式 热带海洋降水 对流垂直结构 总湿稳定度(GMS)
在线阅读 下载PDF
基于Epicentre的数据模型投影工具研究与实现 被引量:3
13
作者 赵海峰 刘一娜 杨国强 《计算机与现代化》 2009年第8期90-92,96,共4页
针对Epicentre数据模型没有提供对自行构筑应用数据模型投影支持的问题,在充分研究Epicentre数据模型和POSC投影理论的基础上,结合中石化数据模型SPDM1.0的自身特点,开发了一套投影辅助工具,完成了SPDM1.0逻辑模型与物理模型之间的数据... 针对Epicentre数据模型没有提供对自行构筑应用数据模型投影支持的问题,在充分研究Epicentre数据模型和POSC投影理论的基础上,结合中石化数据模型SPDM1.0的自身特点,开发了一套投影辅助工具,完成了SPDM1.0逻辑模型与物理模型之间的数据转换。 展开更多
关键词 POSC EPICENTRE SPDM 1.0 投影工具 逻辑模型
在线阅读 下载PDF
华北地区重力势能差水平构造应力分布特征 被引量:2
14
作者 李忠亚 胡敏章 李辉 《大地测量与地球动力学》 CSCD 北大核心 2017年第9期908-912,共5页
采用Crust 1.0地壳模型、SIO V24.1重力场模型和SIO V18.1地形模型计算华北地区的重力势能,并进行动力地形改正以消除岩石圈下地幔运动产生的径向作用力对重力势能的影响。利用有限元方法求解重力势能与水平构造应力之间的平衡方程,得... 采用Crust 1.0地壳模型、SIO V24.1重力场模型和SIO V18.1地形模型计算华北地区的重力势能,并进行动力地形改正以消除岩石圈下地幔运动产生的径向作用力对重力势能的影响。利用有限元方法求解重力势能与水平构造应力之间的平衡方程,得到华北地区的水平构造应力分布。结果表明,华北地区水平构造应力空间分布不均匀,高重力势能区表现为引张状态,低势能区为压缩状态;阴山-燕山断块中北部为高势能区,张应力以N-S方向分布;华北平原断块西南部卫辉周围、东北部葫芦岛和秦皇岛一带以及河淮平原断块西北部郑州附近为低势能区,最大主应力方向为NWW-SEE。 展开更多
关键词 重力势能 构造应力 有限元 CRUST 1.0模型
在线阅读 下载PDF
大气环流模式性能特点分析 被引量:1
15
作者 张诚 刘利 +1 位作者 李锐喆 杨广文 《计算机工程与应用》 CSCD 北大核心 2016年第14期1-6,11,共7页
地球系统模式是模拟气候系统行为和变化的重要工具,在气候研究中扮演着重要的角色。大气环流模式是地球系统模式的一个重要部分。地球科学的快速发展对大气环流模式的分辨率提出越来越高的要求。高性能计算机的发展为更高分辨率大气环... 地球系统模式是模拟气候系统行为和变化的重要工具,在气候研究中扮演着重要的角色。大气环流模式是地球系统模式的一个重要部分。地球科学的快速发展对大气环流模式的分辨率提出越来越高的要求。高性能计算机的发展为更高分辨率大气环流模式的研究提供必要的硬件环境。但是当前并没有针对大气环流模式的高性能计算的特征和需求等方面的研究。中科院大气所(LASG)发展的格点大气环流模式(GAMIL)被选为代表,分析大气环流模式的性能特点,并且建立了性能模型。这些分析和性能模型将为预测未来大气环流模式的性能特征和提升性能提供帮助。 展开更多
关键词 大气环流模式 中科院大气所格点大气环流模式(GAMIL) 性能特点分析 高性能计算
在线阅读 下载PDF
Crust1.0地壳模型及其应用:以长江中下游成矿带为例 被引量:6
16
作者 罗凡 严加永 +3 位作者 付光明 罗磊 陶鑫 王昊 《地质学报》 EI CAS CSCD 北大核心 2020年第2期648-660,共13页
地壳是地球系统的重要组成部分,了解各圈层的结构及相互作用是研究地球物质深部交互过程的核心问题,如何探测地壳内部的物质组成和形态结构一直是地球系统科学的研究热点。随着海量地球探测数据的积累和挖掘,地球科学学家提出了不同细... 地壳是地球系统的重要组成部分,了解各圈层的结构及相互作用是研究地球物质深部交互过程的核心问题,如何探测地壳内部的物质组成和形态结构一直是地球系统科学的研究热点。随着海量地球探测数据的积累和挖掘,地球科学学家提出了不同细节层次的地壳模型,当前最为详细,分辨率最高的全球地壳模型是Crust1.0地壳模型。本文首先详细介绍了Crust1.0地壳模型沉积层厚度和壳幔密度差的数据来源和分布特征。然后,基于Crust1.0地壳模型信息,对长江中下游成矿带及邻区的卫星重力数据进行沉积层校正后,采用变密度界面计算方法,获得的长江中下游地区的Moho界面深度分布。长江中下游成矿带的Moho面形态呈现为"V"字型幔隆带,通过分析矿床、岩体及深大断裂的分布规律与幔隆带形成的关系,进一步证实了长江中下游成矿带深部的地幔隆起是形成巨型矿床的根本原因。研究结果表明,Crust1.0在研究区域地壳结构、成矿动力学深部背景等基础地学和地球系统科学研究中具有广泛的应用前景。 展开更多
关键词 全球地壳模型 Crust1.0 变密度界面反演 长江中下游成矿带 MOHO
在线阅读 下载PDF
CAS-ESM 1.0模式对7月份热带太平洋上层流场异常模态的模拟评估
17
作者 盖泳铭 卢姁 +1 位作者 张东凌 张铭 《气候与环境研究》 CSCD 北大核心 2024年第6期723-734,共12页
利用CAS-ESM 1.0模式模拟得到的1922~2005年共84年的7月份资料,对流场异常作了复EOF分解,并与该模式模拟的1月份结果以及相应的实况(SODA资料)和理论结果作了对比和分析。结果表明:在表层、近表层、次表层及上层底,该EOF分解的第一、二... 利用CAS-ESM 1.0模式模拟得到的1922~2005年共84年的7月份资料,对流场异常作了复EOF分解,并与该模式模拟的1月份结果以及相应的实况(SODA资料)和理论结果作了对比和分析。结果表明:在表层、近表层、次表层及上层底,该EOF分解的第一、二模态空间场中明显流场异常都分布在10°S~10°N,为赤道所俘获。总体上流场异常以纯纬向流动为主;它们均与赤道流系异常及赤道波动有较好对应。从表层到上层底流场异常随海洋深度明显减弱。第一、二模态都具有3~5年的年际变化周期,并以4年的年际变化最明显,并都落在ENSO的变化范围中。这两个模态都无明显年代际变化。次表层第一模态的海温异常为,西太平洋暖池区以及西、中太平洋赤道附近有负异常,在东太平洋赤道区及南美洲沿岸有正异常,两者随时间呈跷跷板变化;第二模态海温异常为,中西太平洋以负异常为主,中东太平洋则以正异常为主,并也呈跷跷板变化,且该变化包括了第一模态的跷跷板变化。本文第一、二模态的性质分别是ENSO的主、次模态。本文时间系数无明显年代际变化是因模式未能很好反映印尼穿越流所致;模式模拟的赤道两侧的明显流场异常宽度要较实况宽一倍;以上这些都表明模式在近赤道处的分辨率还不够高,须进一步提高;此外该模式的物理过程和海气耦合程序也需继续改进和优化。 展开更多
关键词 地球系统模式CAS-ESM 1.0 热带太平洋 7月份流场异常 复EOF分解 模拟评估
在线阅读 下载PDF
Sensitivity Study of Design Parameters of a Railway Route under Vertical Deformations
18
作者 Luiz Fernando de Melo Correia Cassio Eduardo Lima de Paiva 《Journal of Civil Engineering and Architecture》 2014年第5期663-672,共10页
Studying the interaction of components is basic for a railroad project, which is also very important for creating maintenance procedures based on predictions from a model that assumes adequate performance. To determin... Studying the interaction of components is basic for a railroad project, which is also very important for creating maintenance procedures based on predictions from a model that assumes adequate performance. To determine these interactions, which can have a great number of combinations, the use of a computational model is of vital importance, in this case, the program FERROVIA 1.0 (RAILROAD 1.0) was used. A critical study developed the program FERROVIA 1.0, and its variables were characterized based on values observed in the literature. After initial characterization was carried out, a comparative study was performed on the sensitivity between these variables and the indications of significant behavior for a railway deformed by the known load of a wheel. A statistical program was used to correlate the elements. The intention was to launch the program FERROVIA 1.0 and later use it for 2,187 combinations. The data used in these correlations corresponded to the normal values for the elements used in railroad engineering practice. Our main goal is to understand the behavior of the track vertical deflection according to the variation of the scaling of the various elements of the railway, 展开更多
关键词 RAILWAY computational model RAILROAD 1.0.
在线阅读 下载PDF
美国NAVD88高程基准与全球高程基准之间的垂直偏差
19
作者 刘鑫宇 李姗姗 +3 位作者 单建晨 范雕 黄炎 王傲明 《测绘科学技术学报》 2024年第6期601-606,共6页
随着空间探测技术的发展,利用地球重力场模型实现全球高程基准统一成为一种有效的方法。本文联合EGM2008、EIGEN-6C4超高阶地球重力场模型和美国范围内36578个GNSS/水准点,基于重力位差法确定NAVD88高程基准相对于全球高程基准的垂直偏... 随着空间探测技术的发展,利用地球重力场模型实现全球高程基准统一成为一种有效的方法。本文联合EGM2008、EIGEN-6C4超高阶地球重力场模型和美国范围内36578个GNSS/水准点,基于重力位差法确定NAVD88高程基准相对于全球高程基准的垂直偏差。首先通过最新发布的CRUST 1.0地壳密度模型确定美国区域地壳密度,较通常假设地壳密度均匀分布更贴合实际情况;然后根据GNSS/水准点至水准原点的距离划分阈值,实验结果表明阈值取3000 km计算结果的标准差达到最小;最后利用最小二乘法对垂直偏差结果进行优化改善,求出美国高程基准NAVD88相对于全球高程基准的垂直偏差为-0.9566 m。 展开更多
关键词 高程基准 CRUST 1.0模型 美国高程基准NAVD88 垂直偏差 GNSS/水准
在线阅读 下载PDF
蒙脱石负载型零价铁纳米颗粒吸附水体中Cr(Ⅵ)污染物实验研究 被引量:4
20
作者 樊明德 王睿哲 +3 位作者 贾时雨 杨青 贾子豪 邢浩云 《岩石矿物学杂志》 CAS CSCD 北大核心 2018年第5期860-868,共9页
零价铁纳米颗粒具有许多异于本体物质的独特性质,在废水处理方面应用潜力巨大。以蒙脱石为载体和分散剂,通过硼氢化钠液相还原法制备了零价铁纳米颗粒。采用电镜及多种谱学技术手段对所得铁纳米颗粒进行了表征。结果表明,铁纳米颗粒大... 零价铁纳米颗粒具有许多异于本体物质的独特性质,在废水处理方面应用潜力巨大。以蒙脱石为载体和分散剂,通过硼氢化钠液相还原法制备了零价铁纳米颗粒。采用电镜及多种谱学技术手段对所得铁纳米颗粒进行了表征。结果表明,铁纳米颗粒大致呈球状形貌,平均粒径约为55 nm,在蒙脱石表面分散良好,具有零价铁内核-铁氧化物外壳结构,提高了纳米铁在空气氛中的稳定性。通过批次实验考察了负载型铁纳米颗粒净化Cr(Ⅵ)的效率、过程及机理。净化效果受p H值影响显著,在最优p H值为1.0条件下,零价铁内核因其表面氧化膜酸溶而出露,可作为有效成分快速高效去除水体中Cr(Ⅵ)污染物,机理为零价铁将吸附至其表面的Cr(Ⅵ)异相还原为Cr(Ⅲ)而去除。属自发放热吸附过程,动力学行为符合准二级模型,吸附等温线可用Langmuir方程较好拟合。研究成果为新型纳米零价铁材料的制备及其铬污染治理提供了理论支撑。 展开更多
关键词 纳米颗粒 铬污染 零价铁 蒙脱石
在线阅读 下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部