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31.
曹富强  丹利  马柱国 《大气科学》2014,38(2):322-336
将大气—植被相互作用模式AVIM(Atmosphere-Vegetation Interaction Model)与区域环境系统集成模式 RIEMS2.0(Regional Integrated Environment Modeling System Version 2.0)耦合,利用耦合后的AVIM-RIEMS2.0模式在东亚区域选定典型年份进行积分试验,通过模拟结果与观测资料对比分析,从整体上评估耦合模式对东亚区域的模拟能力。结果表明:模式能够较好地模拟850 hPa风场、500 hPa位势高度、气温、降水以及地表热通量空间分布型和季节变化。双向耦合具有动态植被过程的AVIM模式后,RIEMS2.0模拟能力有一定程度的提高。850 hPa风场在冬季的中国东北、华北地区以及夏季的中国东部地区,模拟偏差都减小;500 hPa高度场模拟在中国北方地区改进明显,而在中国南方地区的夏季并没表现出明显的改进趋势。耦合模式改进了RIEMS2.0模式冬季气温模拟偏低而夏季偏高的现象。从区域平均看,耦合模式改善了降水模拟偏多的现象,并使得潜热通量的模拟效果有明显的改进,对感热通量模拟在大部分地区也有改进。总的来看,AVIM-RIEMS2.0耦合模式对中国北方地区模拟改进较为明显,而对中国南方地区,特别是华南地区没有明显的改进。  相似文献   
32.
随着教育信息化的快速发展,网络个性化学习越来越普遍。提升大学生的网络学习能力成为一个重要的研究课题。本文结合Web 2.0技术的特点和优势,以学生学习的个性化、自主性为基础,以测绘专业实践教学改革为依托,探讨了利用Web 2.0技术进行个性化学习测绘实践教学平台建设的意义、可行性和技术路线。  相似文献   
33.
Mapping technologies have made considerable strides in recent decades. Global positioning systems (GPS), remote sensing satellites, Web-based mapping services, and geographic information systems (GIS) have facilitated the collection, distribution, analysis, and ultimately interaction with geospatial information. In particular, portable GPS have altered how individuals participate in mapping. Individuals can use GPS to collect tracings of their personal interactions with the environment. These interactions can then be uploaded to one of many available Web-based mapping services. Once uploaded, the geospatial data can be mapped and shared among the broader community of users. Such volunteered geographic information (VGI) exemplifies the conceptualization of an individual collecting, mapping, and sharing personal geographic information. This paper focuses on challenges surrounding VGI. To help place these challenges in a broader context, specialized Web services and GPS technologies developed for the bicycling community will serve as examples of the current status and future prospects of VGI.  相似文献   
34.
Regional climate models (RCMs) have the potential for more detailed surface characteristic and mesoscale modeling results than general circulation models (GCMs).These advantages have drawn significant focus on RCM development in East Asia.The Regional Integrated Environment Modeling System,version 2.0 (RIEMS2.0),has been developed from an earlier RCM,RIEMS1.0,by the Key Laboratory of Regional ClimateEnvironment for Temperate East Asia (RCE-TEA) and Nanjing University.A numerical experiment covering 1979 to 2008 (simulation duration from 1 January 1978 to 31 December 2008) with a 50-km spatial resolution was performed to test the ability of RIEMS2.0 to simulate long-term climate and climate changes in East Asia and to provide a basis for further development and applications.The simulated surface air temperature (SAT) was compared with observed meteorological data.The results show that RIEMS2.0 simulation reproduced the SAT spatial distribution in East Asia but that it was underestimated.The simulated 30-year averaged SAT was approximately 2.0°C lower than the observed SAT.The annual and interannual variations in the averaged SAT and their anomalies were both well reproduced in the model.A further analysis of three sub-regions representing different longitudinal ranges showed that there is a good correlation and consistency between the simulated results and the observed data.The annual variations,interannual variations for the averaged SAT,and the anomalies in the three sub-regions were also captured well by the model.In summary,RIEMS2.0 shows stability and does well both in simulating the long-term SAT in East Asia and in expressing sub-regional characteristics.  相似文献   
35.
The main purpose of this article is to systematically investigate the influence of offshore fringing reef topography on the infragravity-period harbor oscillations. The infragravity (IG) period oscillations inside an elongated harbor induced by normally-incident bichromatic wave groups are simulated using a fully nonlinear Boussinesq model, FUNWAVE 2.0. Based on an IG wave decomposition method, effects of plane reef-face slopes, reef-face profile shapes and the existence of reef ridge on bound and free IG waves and their relative components inside the harbor are comprehensively studied. For the given harbor and reef ridge, the range of the reef-face slopes and the various profile shapes studied in this paper, results show that the amplitude of the free IG waves inside the harbor increases with the increasing of the reef-face slope; while the bound IG waves inside the harbor seem insensitive to it. The effects of the profile shapes on the IG period waves inside the harbor are closely related to the width of the reef face. The existence of the reef ridge can relieve the bound IG waves to some extent when the incident short wave amplitudes are relatively large, while its effects on the free IG waves are negligible.  相似文献   
36.
An increasing amount of interactive ‘2.0’ crowdsourcing platforms raise awareness and funds for conservation and development projects worldwide. By enabling two-way online collaboration and communication, these ‘conservation and development 2.0’ platforms hoped to provide new impetus and popular legitimacy for conservation and development initiatives in the face of budget cuts and general criticism of the ‘formal’ aid sector after the financial crisis. This paper presents the case of the flagship ‘elephant corridor’ project on the Dutch pifworld.com platform to investigate whether and how the ‘2.0’ element has changed conservation and development in line with these expectations. The paper describes and analyses online and offline dynamics of the project and shows that while online excitement about the project remained high, the concomitant conservation and development promises and imaginations ill related to offline local realities. This rather ‘traditional’ conservation and development disjuncture, however, needs to be understood against the system peculiarities of the politics of online ‘do-good’ 2.0 platforms. The paper concludes that as these peculiarities are significantly intensifying and changing conservation and development dynamics, they do not elude familiar (1.0) disjunctures and might even obscure these further from sight.  相似文献   
37.
38.
结合新疆的65个气象观测站日降水数据,采用连续验证统计方法、分类验证统计方法对RFE2.0遥感降水数据在新疆的适用性进行了评估。结果表明:(1)通过连续验证统计分析,新疆地区平均偏差MBE (Mean Bias Error)总体对日降水量高估,均值为0.4 mm,在0.5 mm内的站点超过70%。RFE2.0遥感降水数据与地面观测站的日降水量之间相关系数R的平均值为0.4,表现为较低的相关性。从偏离真实值情况来说,东疆模拟值和观测值最接近。(2)分类验证统计方法对降水事件FBI (Frequency Bias Index)有所高估。按片区来说,降水事件高估的小值区主要在北疆,高估程度低于全疆平均水平。北疆的正确率POD (Probability of Detection)大于南疆、东疆,同时北疆发生空报率FAR (False Alarm Rate)的可能性也小于南疆、东疆。(3)通过实例验证了RFE2.0在北疆、南疆、东疆的可靠性。以上规律可为RFE2.0在新疆的应用提供科学依据。  相似文献   
39.
基于DERF2.0数据,应用均一化标准差、均方根误差等方法,以2013年乌鲁木齐春季逐日温度及24h变温检验为背景,初步评估了该模式对延伸期春季强降温过程的预报能力。结果表明:(1)逐日气温预报整体偏差随预报时效推进而增大,延伸期预报偏差明显大于中期。(2)旬平均温度的中期预报偏差普遍在-2~-8℃,延伸期的预报偏差最小在0℃左右,最大为-15.5℃。(3)日平均气温以及最高、最低气温的逐日偏差均以冷偏差为主,偏差范围为5~-15℃,延伸期预报偏差范围为-5~-15℃。模式对升温阶段的预报冷偏差随升温加剧而增大,对降温阶段的预报偏差随降温加剧而减小。24h变温偏差主要在5℃范围内变化,延伸期的24h变温偏差比中期预报偏大可达|8|℃以上。(4)DERF2.0模式对中短期温度预报有一定水平,延伸期预报能力下降,可参考价值较弱。(5)对强降温过程的结束日的温度预报偏差小,而对过程初始日的温度预报冷偏差大,造成对降温过程的预报暖偏差大,强降温过程普遍漏报。  相似文献   
40.
采用EZ-USB FX2技术,设计开发了基于USB2.0的海床基自动监测平台数据接口方式。采用三态双向门电路控制存储器模块总线复用实现数据访问;采用直接内存读写方法完成数据传输;采用参数存储器完成参数设置。实验证明在数据传输、参数设置以及低功耗控制方面取得良好效果,提高了系统工作性能。  相似文献   
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