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891.
对1990-2000年新疆铁路沿线地区220个大风灾害日和2000-2010年300个大(暴)雪日灾情进行了分析,以1961-2008年年均冬季最大雪深、1961-2010年年均最大风速和致灾性大风日数及承灾体脆弱性作为铁路沿线雪风灾评价指标,基于GIS空间分析对拟建铁路沿线地区的雪风灾进行了区域划分和致灾性定量分析。结果表明:①冬春季是铁路沿线雪灾高发季。拟建铁路阿勒泰-富蕴段、塔城-额敏段为重雪灾区。在铁路弯道设计、防风墙建设方面应进行严格科学论证,作好积雪防护。②大风致灾事件多发生在4-6月。拟建铁路吐鲁番境内柴窝铺-了墩段位于大风高值区,年均大风日60 d以上,哈密-若羌段40 d左右,塔什库尔干-阿克陶段25 d左右。建议在大风地区修建"挡风墙"并修建防护林带和保护铁路沿线现有稀疏植被。 相似文献
892.
基于谱修正方法的非高斯风场模拟 总被引:1,自引:0,他引:1
为克服基于H erm ite谱修正方法的缺点,减少该方法中计算H erm ite多项式系数所需耗费的大量机时,提出了一种模拟非高斯风压场的新方法,采用非高斯累积分布函数(CDF)映射技术来代替基于H erm ite的概率密度函数(PDF)修正。选择任意边缘PDF模型作为概率目标模型,采用目标功率谱密度(PSD)作为样本函数,通过迭代修正该样本函数,使其收敛于目标概率密度函数和目标功率谱密度。将该方法应用于实际结构的非高斯风场模拟,模拟结果与目标谱符合良好,表明本文方法模拟非高斯风场具有较高的精确度和计算效率。 相似文献
893.
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895.
高原夏季西风异常年500 hPa纬向风季节内振荡特征及其与我国降水的关系 总被引:1,自引:0,他引:1
利用NCEP/NCAR日平均再分析资料及中国596个测站日降水资料,采用带通滤波、小波功率谱、合成分析、相关分析等方法对青藏高原夏季西风异常年500 hPa纬向风季节内振荡特征及其与我国降水和大气环流的关系进行了分析,结果表明:青藏高原夏季500 hPa纬向风季节内振荡以40~60 d周期为主;该季节内振荡在高原西风异常年份表现出异常的传播特征;且高原西风增强年份,我国30°N~40°N范围内的低频降水与高原低频纬向风几乎为同位相,30°N以南地区的低频降水与高原低频纬向风几乎为反位相,东北地区的低频降水落后于高原低频纬向风约1/4位相;高原西风减弱年份,江淮以北的我国北方大部分地区低频降水与高原低频纬向风几乎同位相,江淮地区的低频降水落后于高原低频纬向风约1/4位相。低频降水与低频环流有较好的配置关系 相似文献
896.
采用热化学法处理某海上平台含聚油泥(矿物含量(w)1.30%~3.74%,聚合物含量(w)3.37%~7.42%),研究了反应后分离出的泥水的回注性能,并进行了现场回注试验。实验结果表明:泥水经研磨细化处理后,95%(w)的细化污泥粒径不超过7.86μm,远小于注入地层的平均孔喉直径;在含聚量为1 750 mg/L的注聚液中加入500 mg/L的细化污泥,65℃(油藏温度)下,细化污泥在注聚液中具有很好的稳定性,体系黏度变化小;泥水中的污水与注聚液、采出污水、现场采出液处理系统中使用的各种药剂的配伍性好。现场试验结果表明,将泥水加入注聚液中进行回注,注入井压力保持稳定。 相似文献
897.
基于多层次模糊综合评价方法提出了一种含大规模风电电网综合安全评估模型。首先研究了多层次模糊综合评价方法,在充分分析大规模风电注入功率对电网的影响后,综合考虑风电送出水平、电网静态安全性、暂态稳定性和运行经济性多个指标建立大规模风电注入功率对电网影响的评估模型;最后以甘肃酒泉大规模风电基地为实例,仿真分析大规模风电注入对电网的影响,提出适应该风电基地的模糊评价指标、隶属度函数和评语集,对大规模风电注入功率对电网影响的评估模型计算求解,量化评估该风电送出方案,验证了所提出的评估方法的可行性和有效性。 相似文献
898.
After energy, water is the most critical commodity to be made available to people to keep them alive. Saudi Arabia has vast land and people are living in all regions. Most of these are connected to national grid but some are not, especially in remote areas like in the north, south, and west south. Pumping water in remote areas for domestic needs like agriculture and animals beside human needs is essential and require regular power supply. The present idea of wind-PV-Battery hybrid power system based on 100% renewable source is being proposed to utilize and tested in some of the regions on experimental bases. Of the five locations chosen for the purpose, namely Dhahran, Riyadh, Jeddah, Guriat and Nejran, some are good from both wind and solar intensity point of view some have good winds only and some good solar only. Nearly optimal size of PV-Wind water pumping system is determined for each of these sites considering the availability of solar and wind energy distributions throughout the year in these sites. It is shown that the monthly total water pumping capacity when using nearly optimal PV-Wind water pumping system is fairly uniform throughout the year except for the sites of Guriat and Riyadh. In these sites higher water pumping capacity is observed during the spring and summer months. On the other hand the cost of underground water pumping is found to vary between 6 to 12 US¢/m3 for the five sites considered. 相似文献
899.
Sibila A. Genchi Alejandro J. Vitale M. Cintia Piccolo Gerardo M. E. Perillo 《International Journal of Green Energy》2016,13(4):352-365
An assessment of wind energy potential was carried out in five sites (four onshore and one offshore) in South-West (SW) of Buenos Aires province (Argentina). We use high-resolution wind data (2 and 5 min) for the period 2009–2012. The power law was used to estimate the wind speed at 30, 40, and 60 m height from the anemometer position. Turbulence intensity and wind direction were analyzed. Statistical analyses were conducted using two-parameter Weibull distribution. A techno-economic analysis based on a set of commercial wind turbines was performed in those sites. The results derived from this work indicate that the SW of Buenos Aires province represents a promising area for the wind energy extraction, which would encourage the construction of wind farms for electricity generation. 相似文献
900.
Organophosphorus insecticide residues in farm ditches of the Lower Fraser Valley of British Columbia
Michael T. Wan Sunny Szeto P. Price 《Journal of environmental science and health. Part. B》2013,48(5):917-949
Abstract Farm ditches flowing into three important rivers in the Lower Fraser Valley of British Columbia, Canada, were sampled periodically at seven locations from July to December in 1991, to determine the occurrence and levels of seven organophosphorus (OP) insecticides. Based oh sales records for the year, the uses of OP insecticides in this area were as follows: malathion > diazinon > parathion > dimethoate > azinphos‐methyl > fensulfothion, but no sales of chlorfenvinphos. Residues of parathion, diazinon, fensulfothion, dimethoate and chlorfenvinphos were detected at levels ranging from 1 ‐ 7,785 >μg/kg in cropped soils collected from areas adjacent to the sites for sampling ditch water and sediments. Malathion and azinphos‐methyl were not detected in any of the substrates studied, demonstrating their rapid degradation in the environment. Diazinon and dimethoate were consistently found in ditch water at seven locations, with an average concentration of 0.07 μg/L and 0.27 μg/L, respectively. Fensulfothion and parathion, with an average concentration of 0.08 μg/L and 0.17 μg/L, respectively, were sporadically found in ditch water at two locations. In ditch sediments, diazinon was detected at three locations and fensulfothion at two. The average concentrations of these two insecticides were 16 μg/kg and 9 jug/kg, respectively. The potential impact on aquatic organisms of these OP insecticides in ditches is discussed. 相似文献