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面向移动的协同虚拟地理研讨室 被引量:6
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作者 李文航 龚建华 +1 位作者 张利辉 周洁萍 《武汉大学学报(信息科学版)》 EI CSCD 北大核心 2007年第9期817-820,共4页
探讨了一种新的地理问题研讨方式和研讨环境——面向移动的协同虚拟地理研讨室(mobile-oriented collaborative virtual geographic studio,MCVGS),同时设计出一种MCVGS模型,该模型的协同虚拟环境负责地理问题的研讨,并对现场远程指挥;... 探讨了一种新的地理问题研讨方式和研讨环境——面向移动的协同虚拟地理研讨室(mobile-oriented collaborative virtual geographic studio,MCVGS),同时设计出一种MCVGS模型,该模型的协同虚拟环境负责地理问题的研讨,并对现场远程指挥;而移动客户端负责现场数据的收集,并对决策进行反馈。应用JavaSE和Java ME设计并实现了MCVGS的原型系统,并在出血热宿主动物调查中得到试验性应用。结果表明,MCVGS在现势性地理问题的研讨中可以明显提高工作效率。 展开更多
关键词 协同虚拟地理研讨 移动 地理问题 JAVA SE JAVA ME
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地理演示室的建设规范与使用方法探讨
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作者 郑坚强 《电化教育研究》 北大核心 1999年第1期74-78,共5页
根据笔者对中学地理教学改革的调查研究,针对目前我国中学地理教育改革的现状,笔者认为除了进行中学地理教材改革以外,加快中学地理演示室的建设步伐,推行地理多媒体教学是进行中学地理课堂教学改革的关键。因此。
关键词 地理演示 多媒体教学 现代教育技术 地理教育环境
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基于流媒体的虚拟地理环境研究 被引量:3
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作者 杜蔚 龚建华 +1 位作者 丁刚毅 陈铮 《计算机仿真》 CSCD 2005年第1期180-183,共4页
通过将流媒体技术和虚拟地理环境相结合 ,解决了协同角色不能真实可视化 ,交流信息延迟等问题。该文根据流媒体技术的原理 ,设计了基于流媒体的虚拟地理环境系统结构与功能模块 ,并以虚拟地理研讨室为例建立了原型试验系统 ,实现了视频... 通过将流媒体技术和虚拟地理环境相结合 ,解决了协同角色不能真实可视化 ,交流信息延迟等问题。该文根据流媒体技术的原理 ,设计了基于流媒体的虚拟地理环境系统结构与功能模块 ,并以虚拟地理研讨室为例建立了原型试验系统 ,实现了视频音频的本地播放和网络传输功能。研究表明 ,将流媒体技术与虚拟地理环境相结合 ,可以有效地增强虚拟地理环境中协同工作者之间交流 。 展开更多
关键词 流媒体 虚拟地理环境 分布式虚拟环境 虚拟地理研讨
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基于实践力培养的校园地理实践基地建设
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作者 孙磊 《课程教育研究(学法教法研究)》 2018年第8期69-69,共1页
地理实践力与人地协调观、综合思维、区域认知等并称地理学科四大核心素养,其含义是指人们在考察、调查和模拟实验等地理实践活动中所具备的意志品质和行动能力.《普通高中地理课程标准(2017 修订)》强调地理课程落实在“考察、调查... 地理实践力与人地协调观、综合思维、区域认知等并称地理学科四大核心素养,其含义是指人们在考察、调查和模拟实验等地理实践活动中所具备的意志品质和行动能力.《普通高中地理课程标准(2017 修订)》强调地理课程落实在“考察、调查、模拟实验”等实践活动中,让学生在“真实情景中观察、感悟理解地理环境及其与人类活动的关系,增强社会责任感.”地理实践力的培养离不开抓手,离不开媒介,笔者将承载地理实践力培养的教学用具、功能场室、实践场所等统称为地理实践基地.按照位置,地理实践基地可以分为校园实践基地和校外实践基地两类.校外实践基地牵涉面广,操作难度大,在教学中处于补充和从属地位.校园实践基地位于学校内部,组织教学难度小,安全系数高,是培养地理实践力的主要阵地,也是值得研究和探讨的一个领域. 展开更多
关键词 地理室 地理 气象站 日晷 地震科普馆
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Dynamics models of soil organic carbon 被引量:7
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作者 杨丽霞 潘剑君 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期323-330,共8页
As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and... As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and global change. With development of mathematical models that simulate changes in soil organic carbon, there have been considerable advances in understanding soil organic carbon dynamics. This paper mainly reviewed the composition of soil organic matter and its influenced factors, and recommended some soil organic matter models worldwide. Based on the analyses of the developed results at home and abroad, it is suggested that future soil organic matter models should be developed toward based-process models, and not always empirical ones. The models are able to reveal their interaction between soil carbon systems, climate and land cover by technique and methods of GIS (Geographical Information System) and RS (Remote Sensing). These models should be developed at a global scale, in dynamically describing the spatial and temporal changes of soil organic matter cycle. Meanwhile, the further researches on models should be strengthen for providing theory basis and foundation in making policy of green house gas emission in China. 展开更多
关键词 Soil carbon Soil organic carbon Dynamic model
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Epidemiological trends and geographic variation in hospital admissions for diverticulitis in the United States 被引量:1
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作者 Geoffrey C Nguyen Justina Sam Nitasha Anand 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第12期1600-1605,共6页
AIM:To characterize the increasing incidence and geographic variation of acute diverticulitis.METHODS:Using the nationwide inpatient sample (NIS) we identified a cohort who had been admitted with diverticulitis betwee... AIM:To characterize the increasing incidence and geographic variation of acute diverticulitis.METHODS:Using the nationwide inpatient sample (NIS) we identified a cohort who had been admitted with diverticulitis between 1998 and 2005.We calculated age-,sex-,and region-specific rates of hospitalizations for diverticulitis over time.RESULTS:The age-adjusted hospitalization rate for diverticulitis increased from 61.8 per 100000 to 75.5 per 100 000 between 1998 and 2005,and increased similarly in both sexes.Diverticulitis-associated admissions were male-predominant in those younger than age 45 years but were female-predominant thereafter.Admission rates increased the most among those<45 years,while remaining unchanged for those≥65 years.By 2005,the majority of hospitalized patients were<65 years.Age-adjusted rates of diverticulitis-associated hospitalizations were lower in the West(50.4/100000) compared to the Northeast(77.7/100000),South (73.9/100000),and Midwest(71.0/100000).CONCLUSION:Diverticulitis-associated hospitalizations have steeply risen,especially in young adults.These epidemiological trends vary by geographic region and warrant further investigation into potential dietary and environmental etiologies. 展开更多
关键词 DIVERTICULITIS Geographic variation HOSPITALIZATION Young adults
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Modeled Influence of East Asian Black Carbon on Inter-Decadal Shifts in East China Summer Rainfall 被引量:4
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作者 Rashed MAHMOOD LI Shuang-Lin 《Atmospheric and Oceanic Science Letters》 2011年第6期349-355,共7页
Two inter-decadal shifts in East China summer rainfall during the last three decades of the 20th century have been identified.One shift occurred in the late 1970s and featured more rainfall in the Yangtze River valley... Two inter-decadal shifts in East China summer rainfall during the last three decades of the 20th century have been identified.One shift occurred in the late 1970s and featured more rainfall in the Yangtze River valley and prolonged drought in North China.The other shift occurred in the early 1990s and featured increased rainfall in South China.The role of black carbon(BC) aerosol in the first shift event is controversial,and it has not been documented for the second event.In this study,the authors used Geophysical Fluid Dynamics Laboratory's(GFDL's) atmospheric general circulation model known as Atmosphere and Land Model(AM2.1) ,which has been shown to capture East Asian climate variability well,to investigate these issues by conducting sensitive experiments with or without historical BC in East Asia. The results suggest that the model reproduces the first shift well,including intensified rainfall in the Yangtze River and weakened monsoonal circulation.However,the model captures only a fraction of the observed variations for the second shift event.Thus,the role of BC in modulating the two shift events is different,and its impact is relatively less important for the early 1990s event. 展开更多
关键词 black carbon aerosol inter-decadal climate variability East China summer rainfall
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Simulation of the East Asian Subtropical Westerly Jet Stream with GFDL AGCM (AM2.1) 被引量:6
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作者 HUANG Gang LIU Yong 《Atmospheric and Oceanic Science Letters》 2011年第1期24-29,共6页
The present study validated the capability of the AM2.1,a model developed at NOAA's Geophysical Fluid Dynamics Laboratory (GFDL),in reproducing the fundamental features of the East Asian Subtropical Westerly Jet S... The present study validated the capability of the AM2.1,a model developed at NOAA's Geophysical Fluid Dynamics Laboratory (GFDL),in reproducing the fundamental features of the East Asian Subtropical Westerly Jet Stream (EASWJ).The main behaviors of the EASWJ are also investigated through the reanalysis of observational NCEP/NCAR data.The mean state of the EASWJ,including its intensity,location,structure,and seasonal evolution is generally well-portrayed in the model.Compared with the observation,the model tends to reproduce a weaker jet center.And,during summer,the simulated jet center is northward-situated.Results also demonstrate the model captures the variability of EASWJ during summer well.The results of the empirical orthogonal function (EOF) applied on the zonal wind at 200 hPa (U200) over East Asia for both the observation and simulation indicate an inter-decadal shift around the late 1970s.The correlation coefficient between the corresponding principle components is as great as 0.42 with significance at the 99% confidence level. 展开更多
关键词 East Asian Subtropical Westerly Jet Stream seasonal evolution GCM
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Outdoor thermal environmental research of the mountainous city by GIS
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作者 卢军 陈金花 +1 位作者 高亚锋 陈静 《Journal of Central South University of Technology》 EI 2006年第3期225-228,共4页
The study of urban outdoor thermal environment was carried out in one of the mountainous cities by using geography information system(GIS) technique which is connected with predicting and evaluating models for the out... The study of urban outdoor thermal environment was carried out in one of the mountainous cities by using geography information system(GIS) technique which is connected with predicting and evaluating models for the outdoor thermal environment, monitoring data and simulating data. A prediction and evaluation system were set up. A typical mountainous city, i.e., Yunyang city in Chongqing in China, was taken as an example, its urbanization trend and population growth was predicted and evaluated. The heat island intensity and its trend were simulated, the temperature field, velocity field and the humidity field were analyzed. The results show that GIS is an effective tool to deal with the outdoor thermal environment, especially for the mountainous cities with special geographical particularities. GIS can be used in the environmental management and the city planning especially for the mountainous cities. 展开更多
关键词 outdoor thermal environment GIS heat island mountainous city
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The International Research Group in Geophysics Europe Africa: A Laboratory without Borders in the Earth Science and Environment
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作者 Christine Amory-Mazaudier 《Journal of Life Sciences》 2012年第3期335-341,共7页
It was in 1995 that, at the end of the international project IEEY (International Equatorial Electrojet Year), African and European scientists decided to create the IRGGEA (International Group in Geophysics Europe A... It was in 1995 that, at the end of the international project IEEY (International Equatorial Electrojet Year), African and European scientists decided to create the IRGGEA (International Group in Geophysics Europe Africa) in order to pursue the scientific work started during the IEEY project, The main objective of IRGGEA was to introduce new fields of research in Africa and built teams of African scientists recognized at an international level in these new fields. To reach this goal, we developed days after days methods to manage smoothly a large network of scientists from developed and developing countries. After a short introduction on the field of research developed in the IRGGEA, we present the organization of the work based on sharing practices and the results obtained in terms of scientific publications and socio-cultural aspects as the increase of the number of women and positions for students in their countries. Such an experience is easy to reproduce. 展开更多
关键词 Scientific network ethical rules GEOPHYSICS sustainable research Africa.
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Laboratory investigation of axisymmetric single vacuum well point
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作者 武文俊 姚磊华 魏英杰 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第3期750-756,共7页
Vacuum well point is a new but faint soft ground treatment method. This work focuses on the consolidation behavior of a reconstituted soft clayey specimen under vacuum well point combined with surcharge loading. The l... Vacuum well point is a new but faint soft ground treatment method. This work focuses on the consolidation behavior of a reconstituted soft clayey specimen under vacuum well point combined with surcharge loading. The laboratory test was conducted through a vacuum-surcharge consolidation apparatus, and the vacuum loading scheme was adopted for vacuum pressure application to investigate the vacuum effect on soil consolidation. In the testing process, some key parameters such as vacuum pressure, pore water pressure and settlement deformation were timely recorded. Furthermore, the water content, void ratio and permeability coefficient of samples collected after loading were measured to reflect the consolidation characteristics. By comparing with the membrane system and membraneless system, something different was found for the vacuum well point method. The results indicate that the consolidation behavior of an axisymmetric single vacuum well point is almost identical to the behavior of vacuum preloading combined with prefabricated vertical drain(PVD), except for the distribution of the vacuum pressure along the well drain due to the structure of the vacuum well point. And the vacuum well point method may be useful for the improvement of soft clayey deposit in a certain depth. 展开更多
关键词 soft ground vacuum consolidation vacuum well point systems vacuum pressure
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Tropical Pacific Decadal Variability in Subsurface Temperature
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作者 LIU Qinyu XU Lixiao +1 位作者 LU Jiuyou WANG Qi 《Journal of Ocean University of China》 SCIE CAS 2012年第4期451-454,共4页
The nature decadal variability of the equatorial Pacific subsurface temperature is examined in the control simulation with the Geophysical Fluid Dynamics Laboratory coupled model CM2.1.The dominant mode of the subsurf... The nature decadal variability of the equatorial Pacific subsurface temperature is examined in the control simulation with the Geophysical Fluid Dynamics Laboratory coupled model CM2.1.The dominant mode of the subsurface temperature variations in the equator Pacific features a 20-40 year period and is North-South asymmetric about the equator.Decadal variations of the thermocline are most pronounced in the southwest of the Tropical Pacific.Decadal variation of the north-south asymmetric Sea Surface wind in the tropical Pacific,especially in the South Pacific Convergence,is the dominant mechanism of the nature decadal variation of the subsurface temperature in the equatorial Pacific. 展开更多
关键词 decadal variation asymmetry about equator subsurface temperature variation sea surface wind South Pacific Con-vergence Zone
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Progress of Jinping Underground laboratory for Nuclear Astrophysics(JUNA) 被引量:9
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作者 WeiPing Liu ZhiHong Li +61 位作者 JiangJun He XiaoDong Tang Gang Lian Zhu An JianJun Chang Han Chen QingHao Chen XiongJun Chen ZhiJun Chen BaoQun Cui XianChao Du ChangBo Fu Lin Gan Bing Guo GuoZhu He Alexander Heger SuQing Hou HanXiong Huang Ning Huang BaoLu Jia LiYang Jiang Shigeru Kubono JianMin Li KuoAng Li Tao Li YunJu Li Maria Lugaro XiaoBing Luo HongYi Ma ShaoBo Ma DongMing Mei YongZhong Qian JiuChang Qin Jie Ren YangPing Shen Jun Su LiangTing Sun WanPeng Tan Isao Tanihata Shuo Wang Peng Wang YouBao Wang Qi Wu ShiWei Xu ShengQuan Yan LiTao Yang Yao Yang XiangQing Yu Qian Yue Sheng Zeng HuanYu Zhang Hui Zhang LiYong Zhang NingTao Zhang QiWei Zhang Tao Zhang XiaoPeng Zhang XueZhen Zhang ZiMing Zhang Wei Zhao Zuo Zhao Chao Zhou 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第4期1-7,共7页
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to dire... Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of^(25)Mg(p,γ)^(26)Al,^(19)F(p,α)^(16)O,^(13)C(α,n)^(16)O and ^(12)C(α,γ)^(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given. 展开更多
关键词 direct measurement underground laboratory (25)Mg(p γ)(26)Al (19)F(p α)(16)O (13)C(α n)(16)O and (12)C(α γ)(16)O reactions Gamow window JUNA
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Electrical conductivities of two granite samples in southern Tibet and their geophysical implications 被引量:2
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作者 GUO YingXing WANG DuoJun +5 位作者 ZHOU YongSheng LIU ZaiYang YU YingJie LI DanYang ZHANG DongNing ZHU AiYu 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第8期1522-1532,共11页
There are clear differences in the electrical conductivities of the crustal granites of the Qinghai-Tibet Plateau.Because these granites are among the major rock types on the Qinghai-Tibet Plateau, it is very importan... There are clear differences in the electrical conductivities of the crustal granites of the Qinghai-Tibet Plateau.Because these granites are among the major rock types on the Qinghai-Tibet Plateau, it is very important to detect the electrical conductivity of granites under high temperatures and pressures to study the electrical conductivity structure of this area. Using impedance spectroscopy at a frequency range of 10.1–106 Hz, the electrical conductivity of the muscovite-granite collected from Yadong was investigated at a confining pressure of 1.0 GPa and temperatures ranging from 577 to 996 K, while the electrical conductivity of the biotite-granite collected from Lhasa was investigated at a pressure of 1.0 GPa and temperatures ranging from587 to 1382 K. The calculated activation enthalpies of the Yadong muscovite-granite sample is 0.92 eV in the low-temperature range(577–919 K) and 2.16 eV in the high-temperature range(919–996 K). The activation enthalpies of the Lhasa biotite-granite sample is 0.48 eV in the low-temperature range(587–990 K) and 2.06 eV in the high-temperature range(990–1382 K). The change in the activation enthalpies of the granites at different temperature ranges may be associated with the dehydration of the two samples. The electrical conductivities of the granite samples obtained in the laboratory using impedance spectroscopy correspond well with field observations conducted near the sampling points, both in terms of the actual conductivity values and the observed variations between the low-temperature and high-temperature regimes. This correlation of laboratory and field conductivities indicates that the conductivities of the crustal rocks in the two regions closely correspond to granite conductivities.We calculated the electrical conductivities of muscovite-granite and biotite-granite samples using the effective medium and HS boundary models. When applied to the crustal rocks of southern Tibet, the results of the geophysical conductivity profiles lie within the range of laboratory data. Thus, the electrical characteristics of the crustal rocks underlying the southern Qinghai-Tibet Plateau can largely be attributed to granites, with the large changes to high conductivities at increasing depths resulting from the dehydration of crustal rocks with granitic compositions. 展开更多
关键词 Electrical conductivity High temperature and pressure Granite Southern Tibet Plateau
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