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81.
82.
The problem of the detailed structure of magnetogasdynamic shock waves is investigated. It is assumed that the flow takes place under normal magnetic fieldH
0 and the conductivity of the medium is considered infinite. An approximate analytical solution of the nonlinear differential equations describing the phenomena is obtained. The suggested analytical results in this paper are in good agreement with the previous numerical computations for the thickness and the velocity distribution inside the transition region. In addition, the enthalpy distribution inside the shock front is predicted. 相似文献
83.
An investigation of trends in precipitation volume for the last three decades in different regions of Fars province, Iran 总被引:1,自引:1,他引:0
Hossein Ahani Mehrzad Kherad Mohammad Reza Kousari Mehdi Rezaeian-Zadeh Mohammad Amin Karampour Faezeh Ejraee Saeedeh Kamali 《Theoretical and Applied Climatology》2012,109(3-4):361-382
Under condition of climate changes as global warming, monitoring and detecting trend of precipitation volume is essential and will be useful for agricultural sections. Considering the fact that there were not enough research related to precipitation volume, this study aimed to determine trends in precipitation volume, monthly and annually in different regions of Fars province for the last three decades (33?years period; 1978–2010). Fars province is located in arid and semi-arid regions of Iran, and it plays an important role in agricultural production. Inverse distance weighting interpolation method was used to provide precipitation data for all regions. To analyze the trends of precipitation volume, Mann–Kendall test, Sen’s slope estimator, and 10-year moving average low-pass filter (within time series) were used. The negative trends were identified by the Sen’s slope estimator as well as Mann–Kendall test. However, all the trends were insignificant at the surveyed confidence level (95%). With regards to the application of 10-year moving average low-pass filter, a considerable decreasing trend was observed after around year 1994. Since one of the most important restrictions in agricultural development of the Fars province is lack of sufficient water resources, any changes onward to lack of sufficient precipitation impose impressive pressure and stress on valuable resources and subsequently agricultural production. 相似文献
84.
Hamidreza Ramazi Mohammad Reza Hossein Nejad Aenollah Azizzadeh Firoozi 《Journal of the Geological Society of India》2009,74(2):260-266
This paper is devoted to application of SP, resistivity and mise-a-la-masse method in Khenadarreh (Arak, Iran) graphite deposit
exploration. Mise-a-la-masse method is one of the main geophysical exploration methods used to investigate conductive bodies
with outcrops on the surface or in exploratory pits. By integrating mise-a-la-masse results with other geoelectrical methods,
such as self-potential and resistivity surveys, useful results can be acquired. Powerful survey design, data processing and
interpretation methods can make geoelectrical surveying results more reliable. Here, we applied integrated geoelectrical methods
to explore the Khenadarreh-bala graphite deposit in the Sarband region of the Markazi province, Iran. We present a new and
simple method for processing and interpreting mise-a-la-masse data, which corrects for the effect of distance from the current
electrode in the conductive body. After correction, the residual potential values corresponded with the SP results and the
apparent resistivity pseudosections. The geophysical results were confirmed by drill holes in the study area. 相似文献
85.
Propagation of cylindrical and spherical electron-acoustic solitary waves in unmagnetized plasmas consisting of cold electron
fluid, hot electrons obeying a superthermal distribution and stationary ions are investigated. The standard reductive perturbation
method is employed to derive the cylindrical/spherical Korteweg-de-Vries equation which governs the dynamics of electron-acoustic
solitons. The effects of nonplanar geometry and superthermal hot electrons on the behavior of cylindrical and spherical electron
acoustic soliton and its structure are also studied using numerical simulations. 相似文献
86.
Properties of dust-acoustic solitary waves in a warm dusty plasma are analyzed by using the hydrodynamic model for massive dust grains, electrons, ions, and streaming ion beam. For this purpose, Korteweg-de Vries (KdV) equation for the first-order perturbed potential and linear inhomogeneous KdV-type equation for the second-order perturbed potential have been derived and their analytical solutions are presented. In order to show the characteristics of the dust-acoustic solitary waves are influenced by the plasma parameters, the relevant numerical analysis of the KdV and linear inhomogeneous KdV-type equations are obtained. The dust-acoustic solitary waves, as predicted here, may be associated with the nonlinear structures caused by the interaction of polar jets with the interstellar medium, which is known as Herbig-Haro objects. 相似文献
87.
Water Resources - The scour and flow field patterns with accumulation of debris around bridge piers are completely different due to the reduction of flow area and the increase in depth average... 相似文献
88.
Kocatepe Ayberk Ulak Mehmet Baran Kakareko Grzegorz Ozguven Eren Erman Jung Sungmoon Arghandeh Reza 《Natural Hazards》2019,95(3):615-635
Natural Hazards - Roadway closures magnify the adverse effects of disasters on people since any type of such disruption increases the emergency response travel time (ERTT), which is of central... 相似文献
89.
Vizvári Béla Golabi Mahmoud Nedjati Arman Gümüşbuğa Ferhat Izbirak Gokhan 《Natural Hazards》2019,99(1):571-597
Natural Hazards - In this study, a relief system for a large metropolitan city exposed to serious earthquakes is designed and a top-down approach is applied. Afflicted people’s states and... 相似文献
90.
Acta Geochimica - The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In... 相似文献