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Comparison and evaluation of two highway traffic noise prediction models FHWA and RLS90
公路交通噪声预测模型FHWA与RLS90的比较

Deng Ji,Zhao Jianqiang,Zhang Xiaoning,Liu Chunxiao,Liu Jun,Song Xiancai,
邓佳
,赵剑强,张晓宁,刘春晓,刘珺,宋现才

环境工程学报 , 2012,
Abstract: The FHWA model and the RLS90 model have been used for traffic noise prediction in China for a long time.In order to understand the prediction accuracy of the two models,discrepancies among the RLS90 segmentation model,the RLS90 long straight model and the FHWA model were analyzed theoretically.Field measurement was conducted for verifying the calculation of the three models.The results indicate that the RLS90 model is somewhat superior to the FHWA model in terms of highway traffic noise prediction.
公路交通噪声预测模型FHWA与RLS90的比较  [PDF]
邓佳,赵剑强,张晓宁,刘春晓,刘珺,宋现才
环境工程学报 , 2012,
Abstract: 为了了解我国长期以来使用的两种公路交通噪声预测模型,即美国联邦公路局(FHWA)模型和德国RLS90模型的预测精确性,通过理论分析,比较了RLS90分段模型、RLS90长直线模型、FHWA模型的差异,并通过实际测量值对3种模型的计算结果进行了验证,表明RLS90模型在高速公路交通噪声预测中略优于FHWA模型。
基于FHWA的兰州市道路交通噪声预测模型的建立  [PDF]
石垚,巨天珍,温飞,常成虎,王勤花,曹春,吴永红,贾丽,任正武,杨泓,陈源
环境科学学报 , 2006,
Abstract: 结合美国道路交通噪声污染预测模型(FHWA)和国内学者在该方面的大量研究成果,选择兰州市主、次干道共计52条、142个监测点的建模采样数据,并应用统计学原理分析了影响道路交通噪声的各个因子与道路交通噪声的相关性,最终得出了符合兰州市道路交通特征的噪声污染统计预测模型.随后通过兰州市15个监测点的预测与实测对比验证后发现二者具有较高的一致性,此模型可应用在兰州市道路交通噪声污染的预测评价中.
The Characteristics of Ground Flashes in Beijing and Lanzhou Regions

Qie Xiushu,Guo Changming,Liu Xinsheng,

大气科学进展 , 1991,
Abstract: Over twenty thousand lightning location data obtained by using Lightning Location System (LLS) from Lanzhou and Beijing regions have been analysed to ascertain the characteristics of ground flashes in both regions. The strength of positive flashes is 5 times higher in Lanzhou than in Beijing. The strength of positive flashes is 3 times and 2.2 times as large as negative flashes in Beijing and in Lanzhou respectively. It has been found that the strength of positive and negative flashes is submitted to the normal distribution, and is independent of the characteristics of thunderstorm. So the lightning, strength obtained by DF may be used to forecast the coming of thunderstorm. Although the stroke number in both regions decreases as exponent regulation, the maximum number of return stroke for one lightning in Beijing is more than that in Lanzhou. The peak flash rate occurs in late afternoon for both regions, but the maximum and minimum flash rate appeared an hour earlier in Beijing than in Lanzhou.The relationship between DF display and lightning radiation electric field, discharge current is obtained.
银州柴胡钩沉  [PDF]
王年鹤,郭可跃,袁昌齐,曹锐
中国中药杂志 , 1992,
Abstract: 对曾在历史上被认为是柴胡珍品的银州柴胡进行了分布地区、原植物、药材兴衰过程和品质等方面的考证,并建议对这一种类进行深入研究,以利开发利用。
從意義建構取向探討國立中央圖書館臺灣分館之視障服務 National Taiwan Library Services for Visually Impaired People: A Study Using Sense-Making Approach  [PDF]
Po-Ya Chang,Shan-Ju Lin Chang
Journal of Educational Media & Library Sciences , 2010,
Abstract: 本文以實務問題解決為導向,應用Dervin以使用者為中心的意義建構取向,以國立中央圖書館臺灣分館(簡稱央圖臺灣分館)的視障讀者為研究對象,從使用者的角度探討視障者的資訊尋求行為,試圖回答:視障者利用圖書館的情形(含動機與經驗)、符合視障者需求的服務策略、視障者對服務策略的需求程度等三個研究問題。本研究首先訪談23名視障者(全盲者15人,弱視者8人,年齡自24歲到83歲不等)的圖書館利用行為;其次,參酌訪談結果,擬訂問卷選項,調查280名視障者(全盲者215人,弱視者70人,年齡自9歲到67歲不等)的意見;最後,依據研究結果,分別就央圖臺灣分館、視障圖書館及視障服務機構、與政府單位等三方面,提出建議。 Subjects for this research were chosen from the visually impaired users of the National Taiwan Library (NTL). The Research framework of this study followed the sense-making theory, which is problem-solving-oriented. The purpose of this study is to examine information seeking behavior of visually impaired peo- ple using the library. This study also seeks to discover how visually impaired people use libraries whilst analyzing the barriers and problems they experi- ence, and whether libraries actually met their needs. This study used semi- structured interview and questionnaire to collect data, involving 23 individual interviewees (15 were blind, 8 were partially sighted, aged from 24 to 83) and 280 participants (210 were blind, 70 were partially sighted, aged from 9 to 67). Based on the results, the author of this paper has offered some suggestions to NTL upon the quality and service of collections, librarians, services and equip- ment and environment. The author also has offered some suggestions to visual disability service units and government departments, in order to serve as refer- ences for improving services for visually impaired people.
立塔绞车  [PDF]
李星亮
地质与勘探 , 1978,
Abstract: 立塔是钻探施工中一项繁重的劳动,这里介绍一种省力的立塔绞车,结构如图1。传动比为10,即手轮转10圈,卷筒转1圈。力比关系为1:54,在手轮上施1公斤力,卷简上牵引力为54公斤。立塔时,将四木塔
立字当头论  [PDF]
潘正伯
科技导报 , 1996,
Abstract: 在《科技导报》创刊15周年读者座谈会上,我说“解放以后长时期来,我们在破和立的问题上,搞颠倒了。”有必要对此再多说几句。破和立二者的关系本来是很自然的,如果先没有立,像道家的无,佛家的空,何来得破?
巴州太阳能资源状况研究  [PDF]
宋建新,吴华峰,胡卫,刘润藻,梁汀,李士琦
科技导报 , 2007,
Abstract: 对新疆巴音郭愣蒙古自治州(简称巴州)的太阳能资源分布状况和利用现状进行了较为详细的调查和研究,得到了巴州日照和太阳能辐射情况。在此基础上,对巴州常规能源与太阳能进行了比较,结果显示巴州太阳能十分丰富,远大于其常规能源的总储量。
番 茄 再 生 体 系 的 建 立  [PDF]
乔永旭
北方园艺 , 2010, DOI: 10.11937/bfyy.201017066
Abstract:
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