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971.
选取阿勒泰、阿克苏、和田等8个台站L波段和59-701系统对比观测逐日07时和19时850~100 hPa 10个位势等压面上的高度、气温、露点温度数据,进行差值、离散程度分析,对数据进行t检验,并给出订正方程.研究发现:(1)温度差值07时阿勒泰、库尔勒、民丰等5站为正,哈密、若羌、阿克苏三站为负,正值表明L波段雷达探测的温度值大于59型的温度值,大部分台站19时的差值比07时稳定.(2)高度差值07时和19时4站为正,250 hPa以下差值在0~-10之间,250 hPa以上差值迅速增大,除个别台站外差值最大值均在100 hPa处.(3)07、19时露点温度差值除个别等压面外均为负值,且07时的差值大于19时.(4)大部分台站的高度、温度能通过信度α=0.05的检验,说明L波段与59-701雷达探空高度和气温观测资料无显著性差异.露点温度均未能通过T检验,通过计算给出订正方程. 相似文献
972.
《New Astronomy》2022
We consider an equation of motion for Glashow–Weinberg–Salam model and apply the semiclassical Hamilton–Jacobi process and WKB approximation in order to compute the tunneling probability of W-bosons in the background of electromagnetic field to analyze the quantum gravity effects of charged black hole(BH) in Einstein–Gauss–Bonnet gravity theory. After this, we examine the quantum gravity influences on the generalized Lagrangian field equation. We make clear that quantum gravity effects leave the remnants on the tunneling radiation becomes non-thermal. Moreover, we analyze the graphical behavior of quantum gravity influences on corrected Hawking temperature for spin-1 particles for charged BHs. 相似文献
973.
《Geomechanics and Geoengineering》2013,8(2):127-135
This paper presents the results of approximate analytical solutions to Richards' equation, which governs the problem of unsaturated flow in porous media. The existing methods generally fall within the category of numerical and analytical methods, often having many restrictions for practical situations. In the present study, two approximate analytical methods known as the differential transform method (DTM) and homotopy perturbation method (HPM) were employed to find analytical solutions to Richards' equation. The methods were found to be robust in finding solutions practically identical to those from the existing analytical and numerical methods. Two representative examples were considered in order to evaluate the accuracy of the solutions obtained by DTM and HPM, revealing high level of accuracy in both cases. 相似文献
974.
焦郑高速公路雾天气预报与监测 总被引:2,自引:0,他引:2
分析了焦郑高速公路沿线雾天气气候特征及能见度与最大车流量的关系。利用欧洲中心数值预报产品和单站要素资料,选择预报因子,建立了雾天气预报方程。利用天气雷达进行临近监测预报服务。 相似文献
975.
In the homogeneous and isotropic Friedmann–Robertson–Walker minisuperspace model, it is known that there are no Euclidean wormhole solutions in the pure gravity system. Here it is demonstrated explicitly that in Taub cosmology, which is one of the simplest anisotropic cosmology models, wormhole solutions do exist in pure general relativity in both classical and quantum contexts. Indeed, it is realized that it is the nonvanishing momentum or the energy associated with the anisotropy change, that essentially renders the occurrence of both classical and quantum wormholes possible. 相似文献
976.
977.
考虑多普勒参数的SAR影像距离——共面方程及其定位 总被引:1,自引:0,他引:1
通过对合成孔径雷达(SAR)影像成像几何机理的分析,以传感器位置和姿态作为定向参数,构建了考虑多普勒参数的SAR影像距离—共面方程及基于该方程的SAR影像空中三角测量模型。以登封地区99景0.5 m分辨率机载非0多普勒SAR影像为试验数据,进行了单片定向、无控制点的自由网平差、稀少控制点的区域网平差及带有自检校参数的区域网平差等系列试验。与R-D模型相比,本文模型减少了定向参数的数目,实现了SAR影像与POS数据的联合平差处理,建立的带有自检校参数的SAR影像区域网平差模型,对提高稀少或无地面控制点条件下未进行(或低精度)几何定标SAR影像的区域网平差精度起到了显著作用。较少控制点条件下模型满足了丘陵和山区1∶5000/1∶10000航摄测图对空中三角测量精度的要求。 相似文献
978.
979.
Three transformation models (Bursa-Wolf, Molodensky, and WTUSM) are generally used between two data systems transformation. The linear models are used when the rotation angles are small; however, when the rotation angles get bigger, model errors will be produced. In this paper, we present a method with three main terms: the traditional ? rotation angles θ, φ, ψ are substituted with a,b,c which are three respective values in the anti-symmetrical or Lodrigues matrix; ? directly and accurately calculating the formula of seven parameters in any value of rotation angles; and ? a corresponding adjustment model is established. This method does not use the triangle function. Instead it uses addition, subtraction, multiplication and division, and the complexity of the equation is reduced, making the calculation easy and quick. 相似文献
980.
This study is aimed at evolving a watershed prioritization of reservoir catchment based on vegetation, morphological and topographical parameters, and average annual soil loss using geographic information system (GIS) and remote sensing techniques. A large multipurpose river valley project, Upper Indravati reservoir, situated in the state of Orissa, India, has been chosen for the present work. Watershed prioritization is useful to soil conservationist and decision makers. This study integrates the watershed erosion response model (WERM) and universal soil loss equation (USLE) with a geographic information system (GIS) to estimate the erosion risk assessment parameters of the catchment. The total catchment is divided into 15 sub-watersheds. Various erosion risk parameters are determined for all the sub-watersheds separately. Average annual soil loss is also estimated for the sub-watersheds using USLE. The integrated effect of all these parameters is evaluated to recommend the priority rating of the watersheds for soil conservation planning. 相似文献