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1.
Currently used and newly proposed calculation techniques for the heightof the stable boundary layer (SBL), including the bulk-Richardson-numbermethod, diagnostic equations for the equilibrium SBL height, and a relaxation-typeprognostic equation, are discussed from the point of view of their physical basis andrelevance to experimental data. Among diagnostic equations, the best fit to data exhibits an advanced Ekman-layer height model derived recently with due regard to the role of the free-flow stability. Its extension to non-steady regimes provides a prognostic equation recommended for use in practical applications. 相似文献
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A. Ankilov A. Baklanov M. Colhoun K. -H. Enderle J. Gras Yu. Julanov D. Kaller A. Lindner A. A. Lushnikov R. Mavliev F. McGovern T. C. O'Connor J. Podzimek O. Preining G. P. Reischl R. Rudolf G. J. Sem W. W. Szymanski A. E. Vrtala P. E. Wagner W. Winklmayr V. Zagaynov 《Atmospheric Research》2002,62(3-4)
During an international workshop at the Institute for Experimental Physics of the University of Vienna, Austria, which was coordinated within the Committee on Nucleation and Atmospheric Aerosols (IAMAS-IUGG), 10 instruments for aerosol number concentration measurement were studied, covering a wide range of methods based on various different measuring principles. In order to investigate the detection limits of the instruments considered with respect to particle size, simultaneous number concentration measurements were performed for monodispersed aerosols with particle sizes ranging from 1.5 to 50 nm diameter and various compositions.The instruments considered show quite different response characteristics, apparently related to the different vapors used in the various counters to enlarge the particles to an optically detectable size. A strong dependence of the 50% cutoff diameter on the particle composition in correlation with the type of vapor used in the specific instrument was found. An enhanced detection efficiency for ultrafine hygroscopic sodium chloride aerosols was observed with water operated systems, an analogous trend was found for n-butanol operated systems with nonhygroscopic silver and tungsten oxide particles. 相似文献
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The Effect of Stratification on the Aerodynamic Roughness Length and Displacement Height 总被引：1，自引：0，他引：1
S. S. Zilitinkevich I. Mammarella A. A. Baklanov S. M. Joffre 《Boundary-Layer Meteorology》2008,129(2):179-190
The roughness length, z
0u
, and displacement height, d
0u
, characterise the resistance exerted by the roughness elements on turbulent flows and provide a conventional boundary condition
for a wide range of turbulent-flow problems. Classical laboratory experiments and theories treat z
0u
and d
0u
as geometric parameters independent of the characteristics of the flow. In this paper, we demonstrate essential stability
dependences—stronger for the roughness length (especially in stable stratification) and weaker but still pronounced for the
displacement height. We develop a scaling-analysis model for these dependences and verify it against experimental data. 相似文献
5.
Pavlenko E. P. Sosnovskii A. A. Antonyuk K. A. Antonyuk O. I. Pit’ N. V. Kokhirova G. I. Rakhmatullaeva F. J. Baklanov A. V. 《Astrophysics》2021,64(3):293-305
Astrophysics - Photometric studies of the type SU UMa dwarf nova NY Her were made during 2017 and 2020 at the Crimean Astrophysical Observatory and at the Sanglokh Observatory over a total of 77... 相似文献
6.
Natural-resource space (NRS) is a set of resource-containing components of geographical environment as taken in a spatiotemporal continuum. We suggest different types and levels of NRS: global, national, regional and local; space of homogeneous resources, and territorial combinations of natural resources, and others. Borders are identified as really existing transitional zones between NRS of different types and levels, and institutional boundaries. Ecological-resource space is singled out, given a connectivity of national and regional NRS, with portions of transboundary geosystems going beyond their boundaries. 相似文献
7.
D.?Yu.?TsvetkovEmail author S.?Yu.?Shugarov I.?M.?Volkov N.?N.?Pavlyuk O.?V.?Vozyakova N.?I.?Shatsky A.?A.?Nikiforova I.?S.?Troitsky Yu.?V.?Troitskaya P.?V.?Baklanov 《Astronomy Letters》2018,44(5):315-323
We present the results of our UBVRI photometry for the type II-P supernova SN 2017eaw in NGC6946 obtained fromMay 14 to December 7, 2017, at several telescopes, including the 2.5-m telescope at the CaucasusHigh-Altitude Observatory of the SAIMSU. The dates andmagnitudes atmaximumlight and the light-curve parameters have been determined. The color evolution, extinction, and peak luminosity of SN 2017eaw are discussed. The results of our preliminary radiation–gasdynamic simulations of its light curves with the STELLA code describe satisfactorily the UBVRI observational data. 相似文献
8.
Based on observations of SN 1999em, we determined the physical parameters of this supernova using hydrodynamic calculations including nonequilibrium radiative transfer. Taking the distance to SN 1999em estimated by the expanding photosphere method (EPM) to be D = 7.5 Mpc, we found the parameters of the presupernova: radius R = 450R⊙, mass M = 15M⊙, and explosion energy E = 7 × 1050 erg. For the distance D = 12 Mpc determined from Cepheids, R, M, and E must be increased to the following values: R = 1000R⊙, M = 18M⊙, and E = 1051 erg. We show that one cannot restrict oneself to using the simple analytical formulas relating the supernova and presupernova parameters to obtain reliable parameters for type-IIP presupernovae. 相似文献
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区域可持续发展的指标、标准和限制(英文) 总被引：1，自引：0，他引：1
世界各国包括俄罗斯在内已经出版了大量关于可持续发展的理论研究方面的书籍。但总体而言,在不同结构层次(全球、国家、区域和地方)的可持续发展模型中,区域水平上的模型可能是最复杂和最基础的层次。本文在构建可持续发展模型的框架下,给出了一个区域经济、社会和生态发展的指标体系、标准和限制,并建立了一套评价区域自然资源潜力及其动态变化的方法。首先,对区域层次上达到可持续发展的条件和内容进行分析。其次,给出一个区域经济、社会和生态发展的框架。其中区域发展的经济质量是指其自身资源状况所带来的区域发展能力;区域发展的社会质量是指由区域的人口潜力和社会结构所带来的在一个长时期内稳定的区域人口以及由此提供的高标准生活质量的能力;区域发展的生态质量是指在一个长时期内区域保持其自然资源潜力和高质量环境的能力。区域可持续发展是在一个长时期内(10年)区域高质量的发展,在区域发展质量水平上进行可持续性和平衡性的评价是必要的,为此建立三者之间适当的比例关系。第三,为反映区域间发展的差异,对区域内的经济、社会等进行自然-经济区划以及对每个分区进行相应的指标的计算。这些绝对和相对的可持续发展比率反映了一定时期内实际的状态距离标准值的程度,刻画了区域发展的质量特征。如果这种比率发生变化,或者相对标准值发生动态改变,那么这些比率就可以评估发展的稳定性,以及同时反映了区域发展在质量上的提高或者降低。第四,区域自然资源潜力及其动态变化的评价。第一步是进行局部自然资源分区和把国土自然资源系统作为最复杂的评价对象进行整体考虑。然后对每一个自然资源系统进行动态平衡的计算(这种平衡反映了自然资源的动态和状态)。自然资源潜在的变化可以用实际的或者预测的数据进行计算。 相似文献
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P.Ya.Baklanov 《资源与生态学报(英文版)》2011,(3):283-285
A geographical position and objective processes of globalization become leading factors of the orientation of the Russian east areas in the long-term development to interaction with the countries of the Asian-Pacific region (APR) and also to various natural resources and transport potential of the Pacific Ocean. 相似文献