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791.
L. V. Didkovsky D. L. Judge A. R. Jones E. J. Rhodes J. B. Gurman 《Astronomische Nachrichten》2006,327(4):314-320
An indirect proton flux measuring tool based on discrimination of the energy deposited by protons in 128 × 128 pixel EIT CCD areas outside the solar disk images is presented. Single pixel intensity events are converted into proton incident energy flux using modeled energy deposition curves for angles of incidence ±60° in four EIT spatial areas with different proton stopping power. The extracted proton flux is corrected for both the loss of one‐pixel events in the range of angles of incidence as well as for the contribution to the single pixel events resulting from scattered middle‐energy protons (low‐energy or high‐energy particles are stopped by the EIT components or pass through them, accordingly). A simple geometrical approach was found and applied to correct for a non‐unique relation between the proton‐associated CCD output signal and the incident proton energy. With this geometrical approximation four unique proton incident energy ranges were determined as 45–49, 145–154, 297–335, and 390–440 MeV. The indirect proton flux measuring tool has been tested by comparing Solar Energetic Particles (SEP) flux temporal profiles extracted from the EIT CCD frames and downloaded from the GOES database for the Bastille Day (BD) of 2000 July 14 and the more recent 2005 January 20 events. The SEP flux temporal profiles and proton spectra extracted from the EIT in the relatively narrow energy ranges between 45 and 440 MeV reported here are consistent with the related GOES profiles. The four additional EIT extracted ranges provide higher energy resolution of the SEP data. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
792.
The viability of a complete structural characterization of civil structures is explored and discussed. In particular, the identification of modal (i.e. natural frequencies, damping ratios and modal shapes) and physical properties (i.e. mass and stiffness) using only the structure’s free decay response is studied. To accomplish this, modal analysis from free vibration response only (MAFVRO) and mass modification (MM) methodologies are engaged along with Wavelet based techniques for optimal signal processing and modal reconstruction. The methodologies are evaluated using simulated and experimental data. The simulated data are extracted from a simple elastic model of a 5 story shear building and from a more realistic nonlinear model of a RC frame structure. The experimental data are gathered from shake table test of a 2-story scaled shear building. Guidelines for the reconstruction procedure from the data are proposed as the quality of the identified properties is shown to be governed by adequate selection of the frequency bands and optimal modal shape reconstruction. Moreover, in cases where the structure has undergone damage, the proposed identification scheme can also be applied for preliminary assessment of structural health. 相似文献
793.
The way of extraction of insoluble carbonaceous substance (ICS) from black shales and technique of determination of noble metals (NM) in it by direct arc atomic emission analysis (AEA) were developed. The first results are reported on the determination of mineral-bound noble metals in ICS concentrates, which were extracted from the rocks and ores of the Sukhoi Log, Vernyi, Vasil’evskoe, Kuranakh, Daugyztau, Bakyrchik, Kamennoe, El’dorado, and other deposits. 相似文献
794.
A. Dogan Paktunc 《Contributions to Mineralogy and Petrology》1984,88(4):348-353
Abundant sill-like bodies of serpentinized ultramafic rocks, with associated nickel sulfide deposits, are found on the western side of the Thompson Nickel Belt near the Moak Lake-Setting Lake cataclastic fault zone. The ultramafic rocks range in composition from dunite to orthopyroxenite and feature variable alteration. Chemical variation across the bodies is suggestive of in-situ differentiation controlled mainly by olivine and orthopyroxene. Relative abundances of some elements, incompatible for olivine and orthopyroxene, suggest a parental liquid of komatiitic affinity. Ultramafic and mafic rocks are petrogenetically linked. A high degree of partial melting of mantle material and subsequent low-pressure crystal fractionation are responsible for the spectrum of composition from ultramafic to mafic.Publication 19-84, Ottawa-Carleton Centre for Geoscience Studies 相似文献
795.
S. S. Sengar A. Kumar S. K. Ghosh H. R. Wason 《Journal of the Indian Society of Remote Sensing》2013,41(2):355-363
One of the major after effect of Bhuj Earthquake which occurred on January 26, 2001 was wide spread appearance of liquefaction of soil in the Rann of Kachchh and the coastal areas of Kandla port covering an area of more than tens of thousands of kilometers. Remote sensing data products allow us to explore the land surface parameters at different spatial scales. In this work, an attempt has been made to identify the liquefied soil area using conventional indices from IRS-1D temporal images. The same has been investigated and compared with Class Based Sensor Independent (CBSI) spectral indices, while applying fuzzy based noise classification as soft computing approach using supervised classification. Seven spectral indices have been investigated to identify liquefied soil areas using temporal multi-spectral images. The result shows that the temporal variations can be accounted by using appropriate remote sensing based spectral indices. It is found that CBSI based TNDVI using temporal data yields the best results for identification of liquefied soil areas, while CBSI based SR gives best results for water body identification. 相似文献
796.
797.
A. V. Guglielmi 《Izvestiya Physics of the Solid Earth》2009,45(9):740-743
The paper is dedicated to the 70th anniversary of the formulation of the Leontovich impedance boundary condition. This boundary
condition is applied in geophysics for sounding of the lithosphere and diagnostics of the magnetosphere by electromagnetic
waves. The use of the Leontovich condition is shown to open new possibilities for investigating the anharmonicity of MHD oscillations
of the magnetosphere. The differential impedance equation, which is derived with the aid of the Leontovich boundary condition,
can prove useful in the investigation of the electroconductivity of the lithosphere by the method of inductive sounding. It
is shown within the framework of a simple model that the method of the Leontovich parabolic equation makes it possible to
find a correction to the Leontovich boundary condition caused by the fact that, in general, the relation between the horizontal
components of an electromagnetic field is not local. It is shown that the anharmonicity of MHD oscillations of the magnetosphere
coupled with the nonlocality of the boundary condition on the Earth’s surface can lead to an apparent nonlinearity of the
surface impedance calculated in accordance with the classical technique of magnetotelluric sounding. 相似文献
798.
Simulations of flow for a discrete-fracture model in fractured porous rocks have gradually become more practical, as a consequence of increased computer power and improved simulation and characterization techniques. Discrete-fracture models can be formulated in a lower-dimensional framework, where the fractures are modeled in a lower dimension than the matrix, or in an equi-dimensional form, where the fractures and the matrix have the same dimension. 相似文献
799.
800.
A. S. Rogowski 《International journal of geographical information science》2013,27(4):455-475
Abstract Application of Geographical Information Systems (GIS) to environmental problems requires a spatial delineation of soil properties and some a priori knowledge of their variability. In the U.S.A. estimated soil properties are available from soil surveys published by the National Cooperative Soil Survey. However, information on the extent and nature of their variability is generally lacking. To remedy the situation, variability of selected soil properties measured at farm and watershed scales was compared with published values using geostatistical methods. Results showed that the variability of bulk density and hydraulic conductivity can be estimated by comparing regularized variograms of measured and published values. An overlay method was proposed that combines measured and published delineations of soil properties into an overlay with the properties of both. The technique makes it possible to incorporate variability into a GIS analysis using data available from published soil surveys. 相似文献