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本文通过现有的MICAPS提供的几种物理量和实况降水资料来分析近几年出现的强降水天气,找到一组相关的K指数、不稳定能量、沙氏指数与强降水相对应的指标,来作为预报强降水天气的辅助工具. 相似文献
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B. Junge O. Deji R. Abaidoo D. Chikoye K. Stahr 《The Journal of Agricultural Education and Extension》2013,19(3):257-274
Abstract The main objective of this study was to determine the attitude of farmers towards erosion and the adoption of appropriate soil conservation technologies (SCTs). For the survey, farmers were selected from the communities Esa Oke, Elwure and Owode-Ede and Akoda in Osun State in Nigeria. In the first three communities farmers did receive training on soil conservation, in the fourth not. About 60 farmers were interviewed to obtain information on personal and socio-economic characteristics, awareness of environmental problems, attitude towards erosion control and experiences with SCTs. Statistical data analyses (analyses of frequencies, correlation, t-test, χ2-test) were made to examine possible relationships among parameters and the influence of factors on adoption. Most respondents were advanced in years, responsible for large households and characterized by low levels of income and literacy. Soil erosion was seen as a problem confronting agricultural production only to a small extent. The adoption rate of SCTs was low, as only mulching, cover cropping, contour tillage and cut-off drainage were practised and often rejected. Low labour-demand, the availability of common equipment, low costs of application, ease of practice and compatibility with the existing farming system influenced adoption. The observed positive correlation between level of education, knowledge of appropriate technologies, farming experience and the number of SCTs adopted emphasizes the importance for farmers of education and training. Strengthening agricultural extension agencies for capacity building is an important tool for improving soil conservation in Nigeria. The paper clarifies with specific examples the causes of the low rates of adoption of available technologies, with a reduced impact of research and of efforts to achieve food security and sustainable production at village level. 相似文献
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浅谈老年肺结核的诊断与治疗 总被引：1，自引：0，他引：1
肺结核是严重危害我区群众身体健康的传染病。随着计划免疫工作的普及,儿童结核的发病率逐年下降,成人发病呈上升趋势,而老年病人也逐渐增多。据全国第四次流行病调查显示,60岁以上的结核病发病率呈直线上升趋势。由于结核病是一种呼吸道传染病,健康人吸入带有结核菌的飞沫后可受到结核菌的感染,受到结核菌感染的人只有少数会发生结核病。感染后是否发生结核病,主要取决于所感染的结核菌毒性的强弱和自身抵抗力的高低。医学研究表明,肺也是一个免疫器官,老年人由于全身免疫功能下降,肺免疫力也下降,加上老年肺组织弹性减弱,呼吸道分泌功能减… 相似文献
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城市三维模型的海量特性和当前计算机硬件瓶颈给模型的实时渲染提出了较大的挑战.改进三维地理信息系统(GIS)中数据的组织与管理方式是提高三维场景可视化效率的有效途径,本文提出基于四叉树空间索引对数据进行组织,基于视点的层次模型技术(LOD)对数据进行动态调度,同时提出一种将纹理作为渲染单元重构网格数据的方法,对粗糙模型的渲染进行批处理,有效降低了耗时的渲染次数.实验证明,该方法是高效可行的,渲染帧率稳定在30帧左右,能够满足海量城市三维模型的可视化和实时交互需求. 相似文献
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课堂教学是整个教学工作的中心环节,如何上好一堂课、提高教学效率是教学工作成败的关键。教学的各种因素各方面的条件都集中地体现在课堂教学之中。这里包括教学措施的实施,教学原则的贯彻,教学能力的发挥,学生积极性的调动,教学时间及物质条件的利用等各个方面。 相似文献
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本文结合教学实践，从以下几个方面分析了在目前化学课时较少的情况下，如何加强我院基础化学课对学生的吸引力。为提高学生的学习兴趣和改进教师的授课方法提供了一定的理论基础及教学探讨。 相似文献
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本文从高校图书馆丰富的馆藏文献资源和现代化的信息检索系统之特点，就其在如何推进大学生素质教育中发挥重要作用，结合自己的工作实际提出了几点建议，供管理者参考。 相似文献