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The behavior of quantum dust ion-acoustic (QDIA) shocks in a plasma including inertialess quantum electrons and positrons, classical cold ions and stationary negative dust grains are studied, using a quantum hydrodynamic model (QHD). The effect of dissipation due to the viscosity of ions is taken into account. The propagation of small but finite amplitude QDIA shocks is governed by the Kortoweg-de Vries-Burgers (KdVB) equation. The existence regions of oscillatory and monotonic shocks will depend on the quantum diffraction parameter (H) and dust density (d) as well as dissipation parameter (η 0). The effect of plasma parameters (d,H,η 0), on these structures is investigated. Results indicate that the thickness and height of monotonic shocks; oscillation amplitude of the oscillatory shock wave and it’s wavelength effectively are affected by these parameters. Additionally, the possibility of propagation of both compressive and rarefactive shocks is investigated. It is found that depending on some critical value of dust density (d c ), which is a function of H, compressive and rarefactive shock waves can’t propagate in model plasma. The present theory is applicable to analyze the formation of nonlinear structures at quantum scales in dense astrophysical objects. 相似文献
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Saadat Samane Khalili Davar Kamgar-Haghighi Ali Akbar Zand-Parsa Shahrokh 《Natural Hazards》2013,69(3):1697-1720
Natural Hazards - Spatio-temporal patterns of seasonal streamflow droughts were investigated for the semi-arid Karkheh watershed, located in western Iran with an area of 41,470 km2,... 相似文献
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Mohammad-Reza Azad Mohammad Koneshloo Abolghasem Kamakar Rouhani Hamid Aghajani 《Acta Geophysica》2016,64(2):398-416
To interpret geophysical anomaly maps, it is necessary to filter out regional and sometimes noise components. Each measured value in a gravity survey consists of different components. Upward continuation (UC) is one of the most widely used filters. The shortcoming of this filter is not to consider the spatial structure of the data, and also the fact that the trial and error approach and expert’s judgment are needed to adjust it. This study aims to compare the factorial kriging analysis (FKA) and UC filters for separation of local and regional anomalies in the gravity data of a hydrocarbon field in the southeast sedimentary basins of the East Vietnam Sea. As shown in this paper, FKA method permits to filter out all of the identified structures, while the UC filter does not possess this capability. Therefore, beside general and classic filtering methods, the FKA method can be used as a strong method in filtering spatial structures and anomaly component. 相似文献
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Seyed Adib Banimahd Davar Khalili Shahrokh Zand-Parsa Ali Akbar Kamgar-Haghighi 《Arabian Journal of Geosciences》2017,10(10):223
Performances of conventional and improved soil moisture balance as well as locally calibrated empirical models were evaluated in simulating potential recharge (R) and soil moisture content for a semi-arid foothill region. Models comparison with observed values using lysimeter data during [(2011–2012), (2012–2013)] reveal poor performance of conventional soil moisture balance model, underestimating annual R values. Improved soil moisture balance model provided acceptable estimation of annual R for 2011–2012 by considering the wetting of the near surface soil storage. However, it produced the worst simulation for daily soil moisture content once rainy season was over. Sensitivity analysis revealed that the precision degree of initial soil moisture deficit value would strongly influence estimation of R by improved soil moisture balance model, which can be viewed as a limiting factor. Additionally, locally calibrated model produced the best estimation of annual R and daily soil moisture content, which is suggested for the study region. 相似文献
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Moment tensor inversion of nine events in Iran using INSN data 总被引：1，自引：0，他引：1
Aref Bali Lashak Mehdi Zare Gholamreza Mortezanejad Shahrokh Pour Beyranvand 《Journal of Seismology》2010,14(4):751-760
In this research, moment tensor (MT) inversion procedure in frequency domain is applied to nine events in order to evaluate
the data efficiencies in computing source parameters of earthquakes in Iran. The events are recorded by Iranian National Seismological
Network (INSN) stations, currently comprising 22 broadband stations. For the purpose of this study, first, the inversion procedure
is applied to obtain source parameters. Then, the results obtained here are compared with those of Harvard global centroid
moment tensors (GCMT) in order to estimate their reliabilities. The results show reasonable consistencies with those of Harvard
GCMT within 0.075 uncertainties in logarithmic scalar moment or 0.05 in moment magnitude and 20° in Kagan angle for focal
angles. Furthermore, according to the present research, the calculated source parameters are not significantly sensitive to
the azimuthal gap. 相似文献