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The evaluation of the fundamental period of shear wall buildings considering the flexibility of the base is investigated in this paper. This research is motivated by the discrepancy reported between the formulas used in different building codes and the measurement of real buildings. Both experimental and analytical approaches are used to assess the effect of the base flexibility on the fundamental period of shear wall structures. In total, twenty buildings built on different types of soil are tested under ambient vibration. The fundamental period is identified using a non‐parametric linear model in the frequency domain. The results show that fundamental period formulas used by UBC‐97 and NBCC‐95 are inadequate since they do not include the effect of the foundation stiffness. To improve the estimation of the fundamental period of shear wall buildings, an analytical approach is presented. The structure and the foundation are represented by a continuous‐discrete system. The stiffnesses of the base are represented by translational and rotational discrete springs. The rigidities of these springs are evaluated from the elastic uniform compression of the soil mass and the size of the foundation. The analytical predictions improve the estimation of the fundamental period and keep the computation simple. The error between the measured period and the analytical results is, on average, less than 10%. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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S. G. Mamedov D. M. Kuli-Zade Z. F. Alieva M. M. Musaev F. R. Mustafa 《Astronomy Reports》2016,60(9):848-852
A critical review of determinations of the number of spicules is presented, and the role of both classical and Type 2 spicules in heating and mass balance in the corona is considered. The total number of Type 2 spicules is determined, together with the upward fluxes of energy and mass to which they give rise. The total number of Type 2 spicules on the solar surface is found to be ~105, close to values obtained in other studies. The associated particle flux toward the corona is 2.5 × 1014 cm?2 s?1, an order of magnitude lower than the corresponding flux for classical spicules. The associated energy flux is 104 erg cm?2 s?1, an order of magnaitude lower than estimates obtained in other studies. The results indicate that Type 2 spicules can supply the mass lost from the corona, but are not able to fully explain coronal energy losses. 相似文献
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A.N. Antipov Yu.M. Semenov N.K. Elizbarashvili O.Ya. Sayadian R.M. Mamedov 《Geography and Natural Resources》2009,30(3):286-293
We have developed the planning documents for model territories of a different dimension: the landscape program of Adzharia (Georgia), the landscape structure plan for the Lake Sevan watershed basin (Armenia), and the landscape plan for the Shirvan National Park (Azerbaijan). Variants of the solution of regional natural-ecological problems are proposed, and the measures for implementation of the target concepts are substantiated. 相似文献
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Mamedov V. I. Chausov A. A. Okonov E. A. Makarova M. A. Boeva N. M. 《Geology of Ore Deposits》2020,62(2):163-176
Geology of Ore Deposits - The recognition of the Fouta Djallon–Mandingo territory as an independent bauxite province is substantiated. It is confined to the morphostructure of the same name... 相似文献
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The method of asymmetry change inside Fraunhofer lines profiles is proposed. New digital spectra with high resolution were used. It was shown that asymmetry may change repeatedly by value and a sign inside the spectral line profile. The lines can be classified in three groups on asymmetry changes inside the profiles. 相似文献
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We analyze the sky distribution of various types of cosmic gamma-ray bursts (GRBs): short, long, and intermediate; they are determined by burst duration T 90 (T 90 is the time during which 90% of the burst energy is accumulated). We have found an anisotropy in the distribution of intermediate (2 s < T 90 < 8 s) and short (T 90 < 8 s) GRBs in the form of spots with an enhanced GRB concentration near the Galactic coordinates l=115° and b=30°. Given the BATSE nonuniform exposure function, the statistical significance of the anisotropy is 99.89% for intermediate GRBs and 99.99% for short GRBs. Thus, we suggest that this anisotropy has a natural origin and is not caused by BATSE instrumental effects. 相似文献
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Makarova M. A. Mamedov V. I. Alekhin Yu. V. Shipilova E. S. 《Doklady Earth Sciences》2019,489(1):1297-1300
Doklady Earth Sciences - Results of the hydrogeochemical study of bauxite-bearing lateritic mantles of the Futa Djallon‒Mandingo Province, West Africa, have allowed us to characterize for the... 相似文献
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Mamedov V. I. Shipilova E. S. Boeva N. M. Slukin A. D. Makarova M. A. Vnuchkov D. A. Bortnikov N. S. 《Doklady Earth Sciences》2020,490(1):8-12
Doklady Earth Sciences - Investigation of the comprehensive geological material on the lateritic weathering rocks (Futa Jallon-Mandingo, Africa) led to original identification of a specific horizon... 相似文献
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