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从刚体定轴转动定律可知,提高低风速风力发电机发电能力的方法为提高叶片吸收风能的效率,降低叶片、发电机转子等的机械转动惯量等。低风速风机叶片几何形状优化设计的建议为:降低叶片长度、增大叶片宽度,对鱼类、鸟类进行仿生,并用3D打印制作叶片进行风洞物理实验。
Zheng Yang
semanticscholar +1 more source
Climatic Long Term Trend and Prediction of the Wind Energy Resource in the Gwadar Port [PDF]
利用欧洲中期天气预报中心的ERA-Interim海表10m风场资料,计算巴基斯坦瓜达尔港的风能资源近36年(1979—2014年)期间的历史变化趋势,并利用线性回归和BP神经网络两种方法,对该港的风能资源进行长期年度预测,得到以下结果。1)瓜达尔港夏季的风能资源比冬季丰富,且夏季的稳定性明显好于冬季。2)近36年期间,风能密度、有效风速频率和100W/m2以上能级频率分别以?0.78W/(m2·a),?0.21%/a和?0.22%/a的速度逐年显著递减,且该趋势主要体现在夏季,冬季无显著变化趋势 ...
郑崇伟, 陈璇, 高悦
core +1 more source
β-Glucosidases and β-xylosidases are two categories of enzymes that could cleave out nonreducing, terminal β-D-glucosyl and β-D-xylosyl residues with release of D-glucose and Dxylose, respectively. In this paper, two functional β-glucosidase Dth3 and β-xylosidase Xln-DT from Dictyoglomus thermophilum were heterologously expressed in E.coli BL21 (DE3 ...
Qi, Li +5 more
openaire +3 more sources
利用风况资料和Google Earth卫星影像,分析研究区域的风况特征及沙丘运移特征,并研究沙丘年运移速度、方向及其规律,对防沙治沙手段的提高具有重要意义。结果表明:(1)研究区年平均风速为1.535~1.768 m/s,起沙风平均风速最高值出现在5,6月,全年起沙风平均风速的最低值出现在1月。(2)起沙风和输沙势主要分布在WSW、W、WNW和NW方位。(3)输沙势为0~26 VU,属于低风能环境;风向变率为0.5~0.9,属于中风向变率,钝双峰风况。(4)研究区沙丘年平均移动速度为12.26 m/a ...
赛亚热 +5 more
doaj
为了确定保护性耕作措施对北京周边农田土壤风蚀及颗粒物释放的影响,通过风洞模拟试验,对比不同风速和不同覆盖度下农田土壤风蚀速率及TSP、PM10、PM2.5、PM1的释放差异,并分析了4种细颗粒物在风蚀物中的占比。结果表明:(1)当风速16 m/s时,秸秆覆盖度需达到40%才能达到理想的防风蚀效果。(2)TSP、PM10、PM2.5、PM1 4种细颗粒物的释放量与风速呈正指数函数关系,与覆盖度呈负指数函数关系;随风速的增加,4种细颗粒物的释放能力为A > B1 > B2 > B3 > B4 > B5 ...
邱云霄 +5 more
doaj
E o palhaço o que é? É uma mulher
ResumoEste ensaio traz a fala de uma mulher que descobre em si um palhaço, mesmo atuando, há 13 anos, como palhaça. O encontro com o palhaço Uisquisito ocorreu em 2012, no grupo de teatro Palhaços Trovadores, do qual faço parte há 10 anos. A partir disso, atuar na palhaçaria com gêneros diferentes, feminino e masculino, trouxe-me reflexões não só na ...
openaire +3 more sources
Research of Retrieving Sea Surface Wind Vectors Based on Sentinel-1A Satellite SAR Images [PDF]
海面风场是海气交互界面的重要物理参数,与海洋中绝大多数的海水运动密切相关。海面风场还是海气相互作用的重要媒介,调节了海水和大气之间的物质以及能量输送,对全球气候调节也有着十分重要的作用。 船舶、浮标等观测手段花费高昂,加上海洋面积巨大,可获得的现场海面风场数据十分有限,很难满足大面积海面风场的观测需求。日益发展的卫星遥感技术,为大面积观测风场提供了可能,微波散射计已经成为大面积获取全球海面风场的最重要遥感手段之一,不过微波散射计的空间分辨率通常为25-50km,难以满足对高分辨风场的需求 ...
毕上上
core
Não parece haver, ao menos num primeiro olhar, qualquer ponto de convergência entre a literatura de Lampedusa e a filosofia de Kierkegaard. Contudo, com um pouco mais de investigação, tal percepção revela-se falsa. Ambos os autores situam-se no século XIX e, nesse sentido, há forte conexão entre ambos a partir de uma análise histórica, filosófica e ...
openaire +2 more sources
Preliminary study on assimilation of significant wave heights from T/P altimeter [PDF]
2003-2004 > Academic research: refereed > Publication in refereed journalVersion of ...
Li, CW, Li, YS, Qi, Y, Shi, P, Zhang, Z
core
科尔沁沙地人工杨树(Populus simonii)林生态防风效应研究
通过4~7月对人工杨树林迎风和背风区6倍树高处0.25,0.5,1,2m4个高度风速廓线的观测,定量评价了林地对不同风向及同风向不同风速的生态防护效应,探讨了林地叶面积指数的季节变化对林地生态防风效应的影响。主要结论是:(1)各月可蚀风(风速≥4m/s)的出现频率及风速特征明显不同,4月和5月可蚀风的出现频率及平均风速显著高于6月和7月。(2)各月不同风向的出现频率及风速特征明显不同,4月以SSW、NNW、NW、S、WNW、N和WSW风为主,5月以NW、NNW、W、WSW、WNW和SW风为主,6月以S ...
李锋瑞 张华 赵丽娅 伏乾科
doaj +2 more sources

