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用视觉功效法探究适用于道路照明的新型光源 被引量:10
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作者 张青文 杨春宇 +1 位作者 陈仲林 胡英奎 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第6期781-785,共5页
应用视觉功效法,采用自行研制的"道路照明反应时间测定仪",分别对高压钠灯(HPS)、发光二极管(LED)及电磁感应灯(LVD)三种光源进行了中间视觉下的反应时间和间接的光谱能量分布实测.并根据实测结果,计算出LED和LVD对HPS的亮度... 应用视觉功效法,采用自行研制的"道路照明反应时间测定仪",分别对高压钠灯(HPS)、发光二极管(LED)及电磁感应灯(LVD)三种光源进行了中间视觉下的反应时间和间接的光谱能量分布实测.并根据实测结果,计算出LED和LVD对HPS的亮度对比系数、相对光效及折算光效,由此得出了LED照明安全及节能效果优于HPS和LVD的结论.对光谱能量分布实测结果进行了分析,指出了三种光源光谱特性的内在关系及异同点,为进一步的理论研究提供了实验依据. 展开更多
关键词 道路照明 视觉功效法 背景亮 反应时间 度对比系数 折算光效 光谱能量分布
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Evolution Rules of Urban-rural Development and Inspiration for China's Agriculture
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作者 Liu Ziqiang Li Jing +1 位作者 Lu Qi Liu Yansui 《Chinese Journal of Population,Resources and Environment》 2009年第3期48-54,共7页
Based on urban-rural contrast coefficient,this article designs the agriculture relative development index(ARDI) as indicators measuring the intensity of urban-rural dual structure which is comparable among the countri... Based on urban-rural contrast coefficient,this article designs the agriculture relative development index(ARDI) as indicators measuring the intensity of urban-rural dual structure which is comparable among the countries of the world.This article calculates ARDI of 40 countries from 1980 to 2004.The result shows that ARDI in the developed countries and most of the middle-income countries are rising and yet there are declines in most of the low-income countries.The result also showed that most countries' ARDI will see a decline at the earlier stage of industrialization,so their dual economic structure will also aggravate and urban-rural gap will widen.With the economic development,the tendency will change and ARDI presents a U-shape change overall.The turning point is when a country becomes a middle-income one. 展开更多
关键词 dual economic structure the agriculture relative index urban-rural relation
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