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991.
Eun-Hye Yoo 《International journal of geographical information science》2014,28(2):296-313
Mosquito surveillance programs provide a primary means of understanding mosquito vector population dynamics for the risk assessment of human exposure to West Nile virus (WNv). The lack of spatial coverage and missing observations in mosquito surveillance data often challenge our efforts to predict this vector-borne disease and implement control measures. We developed a WNv mosquito abundance prediction model in which local meteorological and environmental data were synthesized with entomological data in a generalized linear mixed modeling framework. The discrete nature of mosquito surveillance data is accommodated by a Poisson distributional assumption, and the site-specific random effects of the generalized linear mixed model (GLMM) capture any fluctuation unexplained by a general trend. The proposed Poisson GLMMs efficiently account for the nested structure of mosquito surveillance data and incorporate the temporal correlation between observations obtained at each trap by a first-order autoregressive model. In the case study, Bayesian inference of the proposed models is illustrated using a subset of mosquito surveillance data in the Greater Toronto Area. The relevance of the proposed GLMM tailored to WNv mosquito surveillance data is highlighted by the comparison of model performance in the presence of inevitable but quantifiable uncertainties. 相似文献
992.
近二十年全球变暖背景下东亚地区云量变化特征分析 总被引:8,自引:0,他引:8
利用ISCCP的D2云气候资料集,采用趋势分析方法得到了东亚地区1984—2006年各种不同种类云量的变化趋势,并重点分析了全球变暖背景下气温与不同云量变化之间的关系。结果表明:近20年东亚地区总云量和高、低云量呈现波动减少趋势,减少量分别为2.24%、1.65%和1.68%,中云量呈增加趋势,增加量为1.07%;且云量变化存在较大的区域差异。温室效应所导致的东亚地区气温改变和水汽含量变化,是导致云量分布变化的重要原因,在青藏高原、孟加拉湾及热带辐合带区域的气温与高云存在显著负相关,与中、低云存在正相关,而在西太平洋、日本以东以北洋面的气温与低云呈显著负相关,与高云呈正相关。 相似文献
993.
介绍采用问题教学法的必然性,以控制测量学中精密水准测量授课为例,给出了问题教学法的教学方案、教学效果和教学体会。 相似文献
994.
The radiative forcing and climate response due to black carbon(BC) in snow and/or ice were investigated by integrating observed effects of BC on snow/ice albedo into an atmospheric general circulation model(BCC AGCM2.0.1) developed by the National Climate Center(NCC) of the China Meteorological Administration(CMA).The results show that the global annual mean surface radiative forcing due to BC in snow/ice is +0.042 W m 2,with maximum forcing found over the Tibetan Plateau and regional mean forcing exceeding +2.8 W m 2.The global annual mean surface temperature increased 0.071 C due to BC in snow/ice.Positive surface radiative forcing was clearly shown in winter and spring and increased the surface temperature of snow/ice in the Northern Hemisphere.The surface temperatures of snow-covered areas of Eurasia and North America in winter(spring) increased by 0.83 C(0.6 C) and 0.83 C(0.46 C),respectively.Snowmelt rates also increased greatly,leading to earlier snowmelt and peak runoff times.With the rise of surface temperatures in the Arctic,more water vapor could be released into the atmosphere,allowing easier cloud formation,which could lead to higher thermal emittance in the Arctic.However,the total cloud forcing could decrease due to increasing cloud cover,which will offset some of the positive feedback mechanism of the clouds. 相似文献
995.
Hedman JE Rüdel H Gercken J Bergek S Strand J Quack M Appelberg M Förlin L Tuvikene A Bignert A 《Marine pollution bulletin》2011,62(10):2015-2029
The implementation of the EU Marine Strategy Framework Directive necessitates the development of common criteria and methodological standards for marine environmental monitoring and assessment across Europe. Eelpout (Zoarces viviparus) is proposed as a key indicator organism in the Baltic and North Sea regions. This benthic fish species is widely used in ecotoxicological studies and as a bioindicator of local pollution due to its stationary behavior. Eelpout is included in the environmental monitoring program of several Baltic States, covering both chemical and biological effects measurements, and samples have been archived in environmental specimen banks for >15 years. A method for evaluating the frequency of larval aberrations has been suggested as a standardized assessment tool. The large scientific knowledge-base and considerable experience of long-term chemical and biological effects monitoring and specimen banking, make eelpout a suitable species for the assessment of Good Environmental Status in the Baltic and North Seas. 相似文献
996.
In this study, the multi‐intensity seismic response of code‐designed conventional and base‐isolated steel frame buildings is evaluated using nonlinear response history analysis. The results of hazard and structural response analysis for three‐story braced‐frame buildings are presented in this paper. Three‐dimensional models for both buildings are created and seismic response is assessed for three scenario earthquakes. The response history analysis results indicate that the design objectives are met and the performance of the isolated building is superior to the conventional building in the design event. For the Maximum Considered Earthquake, isolation leads to reductions in story drifts and floor accelerations relative to the conventional building. However, the extremely high displacement demands of the isolation system could not be accommodated under normal circumstances, and creative approaches should be developed to control displacements in the MCE. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
997.
A research program is summarized in which collapse of a steel frame structure is predicted numerically and the accuracy of prediction is validated experimentally through earthquake simulator tests of two 1:8 scale models of a 4‐story code‐compliant prototype moment‐resisting frame. We demonstrate that (1) sidesway collapse can occur for realistic combinations of structural framing and earthquake ground motion; (2) P?Δeffects and component deterioration dominate behavior of the frame near collapse; (3) prediction of collapse is feasible using relatively simple analytical models provided that component deterioration is adequately represented in the analytical model; and (4) response of the framing system near collapse is sensitive to the history that every important component of the frames experiences, implying that symmetric cyclic loading histories that are routinely used to test components provide insufficient information for modeling deterioration near collapse. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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针对永久散射体技术和短基线集法所需SAR数据较多的问题,采用时间序列干涉图叠加法监测区域地表沉降,提出利用结构函数作为判断因子提取出受大气扰动较小的干涉图用于叠加分析,以确保大气延迟误差对地表沉降监测结果影响的最小化。利用13景ASAR数据,研究了江苏省盐城市在2003-12~2009-05期间的地面沉降趋势。 相似文献