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1.
从非线性的Boussinesq方程入手,分析湍能发展与风的关系,进而提出了利用风资料判断飞机颠簸出现的一种方法  相似文献   

2.
为提高风速传感器检定校准的精确性,通过几种途径:计算各检定点测量值偏离均值百分比,分析风速传感器测量数据的一致性,评价检定环境的稳定性和气流均匀性;以3次测量数据平均值作为风速传感器示值进行比对,克服因风杯自身和环境因素对测量结果的影响;对风速传感器测量数据的误差处理,分析3种误差曲线间的趋势关系,找出传感器示值中的异常数据;对传感器测量数据和实际风速数据进行线性拟合,进一步验证传感器示值的精确度。得出拟合曲线斜率为1.0213相关系数达到0.99989。研究表明,通过以上方法综合应用,风速传感器检定校准的精确性得到显著提高。  相似文献   

3.
茶悟人生     
喝茶,喝的是一种心境,感觉身心被净化,滤去浮躁,沉淀下的是深思。 茶是一种情调,一种欲语还休的沉默;一种欲笑还颦的忧伤;一种“千红一杯,万艳同窟”热闹后的落寞。 茶是对春天记忆的收藏,在任何一季里饮茶,都可以感受到春日那慵懒的阳光。  相似文献   

4.
化学光谱法测定微量金已实用多年.一般使用杯形上下电极、锥形上电极,本实验在前人基础上将上电极改为凹形电极,与锥形上电极摄谱相比较的优点是:  相似文献   

5.
元家台滑坡位于石门县皂市水库北西侧,现今仍威胁当地10户50余人的生命和财产安全。分析了元家台滑坡的成因机制:斜坡自身稳定性较差,长期降雨和人类活动等因素的共同作用促成了滑坡的发生;利用滑体岩土样品的实验分析数据,结合滑坡形成机制,计算分析了不同工况下元家台滑坡的稳定性:工况一(自重+地面荷载)处于基本稳定状态,工况二(自重+地面荷载+暴雨)为不稳定状态,存在再次滑动可能。  相似文献   

6.
滑坡稳定性评价是滑坡防治中关键问题之一,滑坡失稳破坏判据研究可为滑坡稳定性评价提供支持。为了提高滑坡稳定性评价的精度,以滑坡深部位移监测数据为基础的滑坡失稳破坏判据不失为一种有效方法。基于滑坡深部位移监测数据,引入滑带完整性指标,推导得到了滑带完整性指标与滑坡抗剪强度参数之间呈正比例关系;运用滑坡稳定性计算方法和三峡库区堆积层滑坡简化模型,获得了滑带完整性指标与滑坡的稳定性系数之间呈正比例关系。建立了考虑滑带完整性指标的三峡库区堆积层滑坡失稳破坏判据,即:当滑坡滑带土完整性指标大于滑坡滑带土完整性指标的临界值时,滑坡处于稳定状态;当滑坡滑带土完整性指标小于滑坡滑带土完整性指标的临界值时,滑坡发生失稳破坏。以三峡库区典型堆积层滑坡——五尺坝滑坡为例,通过实例分析发现该判据具备可靠性,对堆积层滑坡适用性好。研究成果表明,滑带完整性指标失稳破坏判据可以用于评价滑坡的稳定状态,为滑坡失稳破坏判据研究提供了一种新思路。  相似文献   

7.
乡下人爱喝酒 一杯乡情下肚 整个村子就醉了 乡下 一条石板路的乡下 摇摇晃晃地 醉倒在门前 连凋零的犬吠 也一朵一朵地漾着酒气乡 下青 草 青青的野草 躺在土地上 躺在梦中 我的心上 满地的绿 在清晨 在遥远的乡下 我的父亲 挥舞着镰刀 收割阳光 也收割绿色的歌谣 青青的野草 在春天里令我心动 在乡下 在我家门前 静静地等待 等我牵着牛 带你回家落 叶 树叶落了 一地的黄叶像睡着了 梦里有许多河流 依然很清澈 树叶落了 风要轻轻地刮过来 那是睡着的心 别把它吹醒…  相似文献   

8.
山东省废弃矿井数量多、分布广,危害程度复杂多样,该文选取矿井类型、井口稳定状态、人口密度、采空区稳定状态、地下水污染程度、土地资源及地形地貌景观影响程度为评价指标,建立了基于层次分析法的废弃矿井危害性评价模型,对其危害性进行了评价研究,可为当地编制废弃矿井治理规划和防灾减灾提供科学依据。  相似文献   

9.
“扣杀”……、“好球”……,赛场上传来阵阵喝彩声。随着参赛选手最后一记扣杀的发力,在一片喝彩声中,省有色地勘局“探矿者杯”系列赛之羽毛球比赛落下帷幕,至此,2013年省有色地勘局“探矿者杯”球类比赛全部结束。  相似文献   

10.
在海口:两斤荔枝、两个木瓜、一杯椰子汁、一张非空调公交车票、一份《南国都市报》或《特区报》、一杯香喷喷的珍珠奶茶在喀什:四斤哈密瓜或葡萄、一大串烤肉、两个小馕、两个小布丁、两个烤包子、两碗酸奶……  相似文献   

11.
中国风能资源空间分布的估算   总被引:6,自引:0,他引:6  
风能是一种清洁的可再生能源,是太阳能的一种转化形式,但风能开发利用的成本比太阳能开发利用的成本要低,它是可再生能源中最具开发前景的一种能源。科学、准确地估算我国风能潜力及其空间分布是国家对风能资源开发中一项极其重要的基础性工作。本文利用全国395个气象站10年、每日4次的气象观测数据,计算了每个气象站所在地区常年有效风能密度和有效风时数,在此基础上,通过空间内插,形成全国范围的风能密度和有效风时数分布数据。结果显示,在全国范围内:有效风能密度大于150W/m2、100~150W/m2、50~100W/m2、小于50W/m2的区域面积占全国国土总面积的百分比分别为2.51%、16.45%、53.39%和27.65%;有效风时数大于5 000h、4 000~5 000h、2 000~4 000h、小于2 000h的区域面积占国土总面积的百分比分别为5.28%、22.19%、53.54%和18.98%。用风能密度和有效风时数两个指标分别表达风能资源潜力虽然存在局部差异,但在总体态势上基本一致,二者之间的相关系数,...  相似文献   

12.
In this paper,the process of wind erosion on two kinds of soil from the agro-pastoral area of Inner Mongolia are studied using wind tunnel experiments,considering the wind speed,blown angle of wind and soil moisture content.The results showed that the modulus of soil wind erosion increases with an increase of wind speed.When the wind speed exceeds a critical value,the soil wind erosion suddenly increases.The critical speed for both kinds of soil is within the range of 7-8m·s-1.For a constant wind speed,the rate of soil wind erosion changes from increasing to falling at a critical soil slope.The critical slope of loam soil and sandy loam soil is 20° and 10°,respectively.Soil moisture content has a significant effect on wind erosion.Soil wind erosion of both soils decreases with an increase of the soil water content in two treatments,however,for treatment two,the increasing trends of wind erosion for two soils with the falling of soil water content are no significant,especially for the loam soil,and in the same soil water content,the wind erosion of two soils in treatment one is significantly higher than treatment two,this indicates reducing the disturbance of soil surface can evidently control the soil wind erosion.  相似文献   

13.
中国北方典型农牧交错区的土壤风蚀危险度研究   总被引:1,自引:0,他引:1  
土壤风蚀及其引发的土地退化、沙化和沙尘暴是中国北方严重的环境问题之一。通过定量评估中国北方典型农牧交错地区土壤风蚀危险程度,可以为区域生态环境的保护和生态修复提供科学支撑。本文基于文献调研、兼顾数据的可获得性,建立了包括风场强度、植被覆盖率、地形起伏度、土壤干燥度等因子在内的风蚀危险程度评价指标体系。同时,依据遥感参数反演和地面气象观测数据,在地理信息系统技术支持下,形成了上述因子的空间分布数据。另外,利用层次分析方法,构建土壤风蚀危险度评价模型,得到研究区土壤风蚀危险度的空间分布。最后,结合研究区土地利用数据,探讨了风蚀危险度空间分布格局的自然环境和土地利用背景。研究表明:研究区土壤风蚀极险型区域面积为1.47×104km2,强险型区域面积为6.09×104km2,危险型区域面积为3.47×104km2,轻险型区域面积为3.45×104km2,无险型区域面积为2.19×104km2。本区土壤风蚀危险度呈现出从东南到西北逐渐增强的趋势,这与区域的植被、气候,以及土地利用的空间格局具有内在的有机联系。  相似文献   

14.
Constructing an industrial system for a large-scale,non-grid-connected wind power industry is a key step towards the diverse utilization of wind power.However,wind power exploitation is not only a technical challenge but an industrial problem as well.The objective of this study is to introduce a concept of large-scale,non-grid-connected wind power(LSNGCWP) industrial zones and establish an evaluation model to assess their industrial arrangement.The data of wind energy,industry,nature resources and socio-economy were collected in this study.Using spatial overlay analysis of geographic information system,this study proposes a spatial arrangement of the LSNGCWP indus-trial zones in the coastal areas of China,which could be summarized as the ’one line and three circles’ structure,which will contribute to the optimization of the industrial structure,advance the wind power technology,coordinate the multi-industrial cooperation,and upgrade the industrial transformation of China’s coastal areas.  相似文献   

15.
Typhoons are one of the most serious natural disasters that occur annually on China's southeast coast.A technique for analyzing the typhoon wind hazard was developed based on the empirical track model,and used to generate 1 000-year virtual typhoons for Northwest Pacific basin.The influences of typhoon decay model,track model,and the extreme value distribution on the predicted extreme wind speed were investigated.We found that different typhoon decay models have least influence on the predicted extreme wind speed.Over most of the southeast coast of China,the predicted wind speed by the nonsimplified empirical track model is larger than that from the simplified tracking model.The extreme wind speed predicted by different extreme value distribution is quite different.Four super typhoons Meranti(2016),Hato(2017),Mangkhut(2018),and Lekima(2019) were selected and the return periods of typhoon wind speeds along the China southeast coast were estimated in order to assess the typhoon wind hazard.  相似文献   

16.
As one of the most serious natural disasters, many typhoons affect southeastern China every year. Taking Shenzhen, a coastal city in southeast China as an example, we employed a Monte-Carlo simulation to generate a large number of virtual typhoons for wind hazard analysis. By analyzing 67-year historical typhoons data from 1949 to 2015 using the Best Track Dataset for Tropical Cyclones over the Western North Pacific recorded by the Shanghai Typhoon Institute, China Meteorological Administration(CMASTI), typhoon characteristic parameters were extracted and optimal statistical distributions established for the parameters in relation to Shenzhen. We employed the Monte-Carlo method to sample each distribution to generate the characteristic parameters of virtual typhoons. In addition, the Yan Meng(YM) wind field model was introduced, and the sensitivity of the YM model to several parameters discussed. Using the YM wind field model, extreme wind speeds were extracted from the virtual typhoons. The extreme wind speeds for different return periods were predicted and compared with the current structural code to provide improved wind load information for wind-resistant structural design.  相似文献   

17.
A multivariate statistical downscaling method is developed to produce regional, high-resolution, coastal surface wind fields based on the IPCC global model predictions for the U.S. east coastal ocean, the Gulf of Mexico(GOM), and the Caribbean Sea. The statistical relationship is built upon linear regressions between the empirical orthogonal function(EOF) spaces of a cross- calibrated, multi-platform, multi-instrument ocean surface wind velocity dataset(predictand) and the global NCEP wind reanalysis(predictor) over a 10 year period from 2000 to 2009. The statistical relationship is validated before applications and its effectiveness is confirmed by the good agreement between downscaled wind fields based on the NCEP reanalysis and in-situ surface wind measured at 16 National Data Buoy Center(NDBC) buoys in the U.S. east coastal ocean and the GOM during 1992–1999. The predictand-predictor relationship is applied to IPCC GFDL model output(2.0?×2.5?) of downscaled coastal wind at 0.25?×0.25? resolution. The temporal and spatial variability of future predicted wind speeds and wind energy potential over the study region are further quantified. It is shown that wind speed and power would significantly be reduced in the high CO_2 climate scenario offshore of the mid-Atlantic and northeast U.S., with the speed falling to one quarter of its original value.  相似文献   

18.
基于空间插值的风场模拟方法比较分析   总被引:1,自引:0,他引:1  
计算流体动力学方法是目前风场空间格局模拟的主要方法之一,该方法由于受到软硬件局限,多应用于小尺度的风场模拟及分析。该方法精确程度极大地依赖于3D建模的精细程度和迭代计算模型的准确程度,与现实风场的发育过程存在明显差异。而随着物联网技术的发展,我们可通过大量的现场传感器进行风场数据的实时采集,为风场动态实时化模拟提供精确的参数。为了确定风场动态实时化模拟的最佳方法,本文以中国科学院城市环境研究所园区内32个风场传感器的月平均风速数据为研究案例,综合分析了反距离权重插值、全局多项式插值、局域多项式插值、径向基函数插值、最近邻域法插值、普通克里格插值6种空间插值方法,并采用交叉验证的方法对插值结果进行比较。结果表明,反距离权重插值在模拟的误差范围、模拟的准确度、反映极值的能力上优于其他5种方法,为1:500尺度的风场空间格局模拟提供了参考。  相似文献   

19.
?????й?????????????б???????????????PET??????????????????????????????????????????????????????????????????????б??2008-2012??05?1???????????о????????????????0.13??0.33 Hz??????????????????????????????????????????????????棬????????庣???6???????磬??÷?????????????????????ε???????????????7???????????3????????????????????0.1 Hz????????????  相似文献   

20.
Coupled effects on a single point mooring(SPM) system subjected to the combined action of wind,waves and current are studied in this paper. Due to the complicatedness of the sea state and the huge size of the vessel,physical experimental study is both time consuming and uneconomical,whereas the numerical study is cost-effective and DNV software provides powerful SESAM software in solving the issues. This paper focuses on the modeling process of the SPM system,catenary equilibrium calculation,static analysis of the vessel in three different scenarios,and dynamic response simulation of the SPM system under environmental excitations. The three scenarios in study are as follows:the SPM is under the combined function of(a) wind,waves and current,(b) wind and waves,(c) current and waves. They are so set that one can compare the contributions of different types of loads in both static and dynamic studies. Numerical study shows that wind and current are the two major factors contributing to the mooring line tension,and surge and sway are the two dominant motions of the moored vessel subjected to environmental excitations.  相似文献   

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