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111.
112.
Intense research and refinement of the tools used in performance-based seismic engineering have been made, but the maturity and accuracy of these methods have not been adequately confirmed with actual data from the field. The gap between the assumed characteristics of actual building systems and their idealized counterparts used for analysis is wide. When the randomly distributed flaws in buildings as they exist in urban areas and the extreme variability of ground motion patterns combine, the conventional procedures used for pushover or dynamic response history analyses seem to fall short of reconciling the differences between calculated and observed damage. For emergency planning and loss modeling purposes, such discrepancies are factors that must be borne in mind. Two relevant examples are provided herein. These examples demonstrate that consensus-based analytical guidelines also require well-idealized building models that do not lend themselves to reasonably manageable representations from field data. As a corollary, loss modeling techniques, e.g., used for insurance purposes, must undergo further development and improvement. 相似文献
113.
Data on the ion-salt, microcomponent, gas, microbiological, and isotopic composition of water and the results of studies of
the equilibriums in the water-rock system are used to analyze the formation processes of the composition of Tersinskie carbonic-acid
mineral water and their genesis. 相似文献
114.
We present a detailed analysis of solar acoustic mode frequencies and their rotational splittings for modes with degree up to 900. They were obtained by applying spherical harmonic decomposition to full-disk solar images observed by the Michelson Doppler Imager onboard the Solar and Heliospheric Observatory spacecraft. Global helioseismology analysis of high-degree modes is complicated by the fact that the individual modes cannot be isolated, which has limited so far the use of high-degree data for structure inversion of the near-surface layers (r>0.97R ⊙). In this work, we took great care to recover the actual mode characteristics using a physically motivated model which included a complete leakage matrix. We included in our analysis the following instrumental characteristics: the correct instantaneous image scale, the radial and non-radial image distortions, the effective position angle of the solar rotation axis, and a correction to the Carrington elements. We also present variations of the mode frequencies caused by the solar activity cycle. We have analyzed seven observational periods from 1999 to 2005 and correlated their frequency shift with four different solar indices. The frequency shift scaled by the relative mode inertia is a function of frequency alone and follows a simple power law, where the exponent obtained for the p modes is twice the value obtained for the f modes. The different solar indices present the same result. 相似文献
115.
Doklady Earth Sciences - The data on the ice distribution in the Franz Josef Land Archipelago area during the 2010/2011 and 2014/2015 ice seasons depending on climate oscillations are presented... 相似文献
116.
S. G. Sichevskij 《Astronomy Reports》2017,61(3):193-205
A technique for determining a star’s radius from its atmospheric characteristics (effective temperature, surface gravity, and metallicity) is realized based on modernmodel computations of the stellar internal structure and evolution. The atmospheric characteristics can also be used to find the mass and luminosity of the star. The star’s rate of evolution and the initial mass function are taken into account when determining the stellar characteristics, increasing the correctness of the results. Computations of stellar evolution of with and without the stellar rotation taken into account make it possible to remove ambiguity due to missing data on the star’s rotational velocity. The results are checked and uncertainties estimated using stars occupying two heavily populated regions in the Hertzsprung–Russell diagram that have been well studied using various methods: the main sequence and red giant branch. Good agreement with the observations is achieved; there are almost no systematic deviations of the derived point estimates of the fundamental characteristics. The metallicities of the individual components of eclipsing variable stars are estimated using observational data on for such stars displaying lines of both components in their spectra. These metallicities were determined as a function of the stellar masses in a way that eliminates systematic deviations in the derived fundamental characteristics. 相似文献
117.
Veselkin D. V. Tretyakova A. S. Senator S. A. Saksonov S. V. Mukhin V. A. Rozenberg G. S. 《Doklady Earth Sciences》2017,476(1):1113-1115
Doklady Earth Sciences - An analysis of data on the species abundance of flora in 89 cities (urban flora) of the Russian Federation facilitated determination of its main factors. It has been... 相似文献
118.
K. K. Edelshtein M. G. Grechushnikova Yu. S. Datsenko V. V. Puklakov 《Water Resources》2012,39(4):432-445
The objectives of diagnostic calculations using mathematical models of reservoirs are formulated. The structure of a box hydrological model GMV-MGU is described, and the results of calculation of daily water balance, internal heat exchange structure, and heat balance of individual areas in the Mozhaisk and Rybinsk reservoirs are given. First results of calculation of variations in mean daily phytoplankton biomass in the near-dam pool of a weakly eutrophic water body in period of spring (diatoms) and summer (blue-green) blooming are presented. 相似文献
119.
N. V. Kabychenko G. G. Kocharyan D. V. Pavlov A. N. Besedina 《Seismic Instruments》2012,48(3):214-217
A procedure for eliciting displacements in tidal waves from seismograms of broadband velocimeters like STS-2 and KSESH-R and the evaluation conversion of these displacements into vertical or volumetric deformation is proposed. 相似文献
120.
Hong-Di He Wei-Zhen Lu 《Stochastic Environmental Research and Risk Assessment (SERRA)》2012,26(8):1053-1061
This paper reports an investigation on the periodic variation of pollutant levels at a typical traffic intersection of Hong Kong. Carbon monoxide, carbon dioxide and particulate matters (PM x ) were measured respectively and the measured data show periodic variations with the traffic signal intervals. The power spectral density (PSD) approach was used to inspect the trends and periodic oscillations of measured pollutants. Singular spectrum analysis was applied to decompose the measured data into statistically significant non-linear trends and oscillations in the process. From the results, most of the trends tend to increase due to the upcoming rush hour during the experiment. In addition, all the oscillations changed regularly with a period of 136?s, which is coincident with the traffic signal period and the frequency calculated by using PSD. The trends, together with the oscillations, collectively explain the most percentage of the variability of the data in the time series and provide the principal components of the data in understanding the periodic variation of the pollutant concentration. It can be deduced that vehicle emission is the major contributor to the air pollution in downtown area and pedestrians should be more alerted when crossing the busy traffic intersections. 相似文献