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11.
Ashraf Samaneh AghaKouchak Amir Nazemi Ali Mirchi Ali Sadegh Mojtaba Moftakhari Hamed R. Hassanzadeh Elmira Miao Chi-Yuan Madani Kaveh Mousavi Baygi Mohammad Anjileli Hassan Arab Davood Reza Norouzi Hamid Mazdiyasni Omid Azarderakhsh Marzi Alborzi Aneseh Tourian Mohammad J. Mehran Ali Farahmand Alireza Mallakpour Iman 《Climatic change》2019,152(3-4):379-391
Climatic Change - By combining long-term ground-based data on water withdrawal with climate model projections, this study quantifies the compounding effects of human activities and climate change... 相似文献
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This study focuses on the development of a farm of tidal turbines in the Khuran Channel. The important factors include the location of turbines and their hydrodynamic effects on the environment. A three-dimensional circulation model for the Persian Gulf is employed for the comprehensive evaluation of the tidal energy potential throughout the study area. The model is validated by using in situ observations of water level and current data.The appropriate potential points for extracting the tidal e... 相似文献
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Adnan Aslam Mubasher Jamil Davood Momeni Ratbay Myrzakulov Muneer Ahmad Rashid Muhammad Raza 《Astrophysics and Space Science》2013,348(2):533-540
In literature usual point like symmetries of the Lagrangian have been introduced to study the symmetries and the structure of the fields. This kind of Noether symmetry is a subclass of a more general family of symmetries, called Noether gauge symmetries (NGS). Motivated by this mathematical tool, in this paper, we study the generalized Noether symmetry of quintom model of dark energy, which is a two component fluid model with quintessence and phantom scalar fields. Our model is a generalization of the Noether symmetries of a single and multiple components which have been investigated in detail before. We found the general form of the quintom potential in which the whole dynamical system has a point like symmetry. We investigated different possible solutions of the system for diverse family of gauge function. Specially, we discovered two family of potentials, one corresponds to a free quintessence (phantom) and the second is in the form of quadratic interaction between two components. These two families of potential functions are proposed from the symmetry point of view, but in the quintom models they are used as phenomenological models without clear mathematical justification. From integrability point of view, we found two forms of the scale factor: one is power law and second is de-Sitter. Some cosmological implications of the solutions have been investigated. 相似文献
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Davood M. Yosefnejad Thorsten J. Nagel Nikolaus Froitzheim 《Swiss Journal of Geoscience》2017,110(2):613-630
The Val-de-Ruz syncline is a northeast-southwest trending, rhomb-shaped synclinal basin in the internal part of the central Jura Mountains. The Mesozoic sediment succession is decoupled from the basement by a décollement horizon in Middle Triassic evaporite-bearing layers at depth and folding is associated with southeast-dipping thrust splays rooting into this décollement. The folds and thrusts also interfere with a system of N-S striking, sinistral strike-slip faults. A 3D model was constructed from the following input data: A digital elevation model, the 1:25,000 geological map of Switzerland, published contours of the top of basement based on drilling and seismics, and nine newly constructed cross-sections. The latter are based on surface geology and published seismic data. Cross-sections parallel to the northwestward transport direction, i.e. perpendicular to the overall strike, are line balanced. Anticlines are interpreted as faulted detachment folds, which initiated by buckling and associated flow of evaporites from synclinal to anticlinal areas. Anticlines were later broken by northwest-vergent thrusts and subsequently developed into fault-propagation folds during décollement from the basement and northwestward translation. The model assumes no faulting in the pre-Mesozoic basement and no hidden flat-ramp tectonics in the subsurface in order to account for structurally high positions. As a consequence, the modelled cumulative, post-deformation thickness of Triassic strata locally exceeds 1500 m, which we find in accordance with regional observations. From the geological 3D model, new cross-sections in any desired orientation and tectonic thickness variations of the layers can be extracted. The three output cross-sections presented are in excellent agreement with published reflection seismic data. The most important features of our model are (1) large thickness variations due to lateral flow of evaporites, and (2) new and plausible explanation of structural highs in terms of accumulation of Triassic strata by lateral flow. 相似文献
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1D joint multi‐offset inversion of time‐domain marine controlled source electromagnetic data 
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下载免费PDF全文 The accurate estimation of sub‐seafloor resistivity features from marine controlled source electromagnetic data using inverse modelling is hindered due to the limitations of the inversion routines. The most commonly used one‐dimensional inversion techniques for resolving subsurface resistivity structures are gradient‐based methods, namely Occam and Marquardt. The first approach relies on the smoothness of the model and is recommended when there are no sharp resistivity boundaries. The Marquardt routine is relevant for many electromagnetic applications with sharp resistivity contrasts but subject to the appropriate choice of a starting model. In this paper, we explore the ability of different 1D inversion schemes to derive sub‐seafloor resistivity structures from time domain marine controlled source electromagnetic data measured along an 8‐km‐long profile in the German North Sea. Seismic reflection data reveal a dipping shallow amplitude anomaly that was the target of the controleld source electromagnetic survey. We tested four inversion schemes to find suitable starting models for the final Marquardt inversion. In this respect, as a first scenario, Occam inversion results are considered a starting model for the subsequent Marquardt inversion (Occam–Marquardt). As a second scenario, we employ a global method called Differential Evolution Adaptive Metropolis and sequentially incorporate it with Marquardt inversion. The third approach corresponds to Marquardt inversion introducing lateral constraints. Finally, we include the lateral constraints in Differential Evolution Adaptive Metropolis optimization, and the results are sequentially utilized by Marquardt inversion. Occam–Marquardt may provide accurate estimation of the subsurface features, but it is dependent on the appropriate conversion of different multi‐layered Occam model to an acceptable starting model for Marquardt inversion, which is not straightforward. Employing parameter spaces, the Differential Evolution Adaptive Metropolis approach can be pertinent to determine Marquardt a priori information; nevertheless, the uncertainties in Differential Evolution Adaptive Metropolis optimization will introduce some inaccuracies in Marquardt inversion results. Laterally constrained Marquardt may be promising to resolve sub‐seafloor features, but it is not stable if there are significant lateral changes of the sub‐seafloor structure due to the dependence of the method to the starting model. Including the lateral constraints in Differential Evolution Adaptive Metropolis approach allows for faster convergence of the routine with consistent results, furnishing more accurate estimation of a priori models for the subsequent Marquardt inversion. 相似文献
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This article presents the results of deterministic and probabilistic seismic hazard analyses (DSHA and PSHA) of the city of Hamedan and its neighboring regions. This historical city is one of the developing cities located in the west of Iran. For this reason, the DSHA and PSHA approaches have been used for the assessment of seismic hazards and earthquake risk evaluation. To this purpose, analyses have been carried out considering the historic and instrumented earthquakes, geologic and seismotectonic parameters of the region covering a radius of 100?km, keeping Hamedan as the center. Therefore, in this research, we studied the main faults and fault zones in the study area and calculated the length and distance of faults from the center of Hamedan. In the next step, we measured the maximum credible earthquake (MCE) and peak ground acceleration (PGA) using both DSHA and PSHA approaches and utilized the various equations introduced by different researchers for this purpose. The results of DSHA approach show that the MCE-evaluated value is 7.2 Richter, which might be created by Nahavand fault activities in this region. The PGA value of 0.56?g will be obtained from Keshin fault. The results of PSHA approach show that the MCE-evaluated value is 7.6 Richter for a 0.64 probability in a 50-year period. The PGA value of 0.45?g will be obtained from Keshin fault. Seismic hazard parameters have been evaluated considering the available earthquake data using Gutenberg?CRichter relationship method. The ??a?? and ??b?? parameters were estimated 5.53 and 0.68, respectively. 相似文献
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Surajit Chattopadhyay Abdul Jawad Davood Momeni Ratbay Myrzakulov 《Astrophysics and Space Science》2014,353(1):279-292
We work on the reconstruction scenario of pilgrim dark energy (PDE) in f(T,T G ). In PDE model it is assumed that a repulsive force that is accelerating the Universe is phantom type with (w DE f(T,T G ) models and correspondingly evaluate equation of state parameter for various choices of scale factor. Also, we assume polynomial form of f(T,T G ) in terms of cosmic time and reconstruct H and w DE in this manner. Through discussion, it is concluded that PDE shows aggressive phantom-like behavior for s=?2 in f(T,T G ) gravity. 相似文献
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Davood Raeisi Hassan Mirnejad Christopher McFarlane Maryam Sheibi Shahrouz Babazadeh 《International Geology Review》2020,62(13-14):1815-1827
ABSTRACT The Tafresh plutons that include Ahmadabab diorite, Vasfonjerd monzonite, Mehrezamin diorite and Chahak diorite, located to the east of Tafresh city, north-central Iran, are part of Urumieh-Dokhtar magmatic arc. U-Pb dating of zircon grains provides emplacement ages of 22.3 ± 1 Ma for the Ahmadabad diorite, and tightly clustered ages of 22.2 ± 0.2 Ma, 21.3 ± 0.2 Ma, and 21.7 ± 0.4 Ma for Vasfonjerd monzodiorite, Mehrezamin diorite-monzonite, and Chahak diorite-monzonite plutons, respectively. These rocks are metaluminous to weakly peraluminous, calc-alkaline, and characterized by enrichment in light rare earth elements, Nb-Ta negative anomalies, and high LILE/HFSE ratios. Tafresh plutonic rocks originated from a parental magma source and experienced different degrees of partial melting. Geochemical signatures of Tafresh plutonic rocks, such as a wide range of Y/Nb (2.7–8.4) and low Zr/Nb (19.5–35.) ratios, Nb/Ta (11.46–18.15), argue for mantle–crust interaction during generation of Tafresh magmas. Relatively low Nb/La ratios further indicate that the lithospheric mantle played a significant role in melt generation. HREE signatures (i.e. decrease Dy/Yb with increasing SiO2) preclude substantial involvement of garnet either in the residue, both during partial melting and fractionation of the magma. The plutons are a product of final stages of subduction-related magmatism prior to the collision between the Arabian and Eurasian tectonic plates. 相似文献
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Behnam Atazadeh Leila Halalkhor Mirkalaei Hamed Olfat Abbas Rajabifard Davood Shojaei 《地球空间信息科学学报》2021,24(3):387-402
Cadastral surveying plays an important role in defining legal boundaries of land and property. The current practice for recording cadastral survey data mainly relies on 2D digital or analog documents. This practice is efficient for simple land parcels but can be challenged in complex building developments. To address the issues stemmed from 2D methods of representing cadastral survey data, 3D spatial information models can be considered as a viable solution for managing cadastral survey data. Building Information Modeling (BIM) enables colsslaborative 3D management of the design, construction, and operation of buildings. There have been extensive studies conducted to investigate the connectivity between BIM and 3D cadaster. Most of these studies focus on managing legal information, such as ownership boundaries and attributes, in BIM-based environments. However, there is limited investigation on how survey- ing measurements can be mapped into BIM. In this study, the proposed method for integrating the cadastral survey data into the BIM environment includes identifying cadastral survey requirements, using BIM entities relevant to cadastral survey data, enrichment of a BIM proto- type, and evaluation of the prototype. The major contribution of this study is to demonstrate the storage of cadastral survey data such as survey marks and traverse lines in the BIM environment. Therefore, this research contributes to the further enrichment of BIM with incorporating data elements related to cadastral surveying practices. It is confirmed that current BIM-based tools provide restricted capabilities for explicit management and visualiza- tion of cadastral survey data. This limitation can be addressed in the future enhancements of BIM in terms of supporting important elements for cadastral survey data. 相似文献
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