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Hafeez Amna Ehsan Muhsan Abbas Ayesha Shah Munawar Shahzad Rasim 《Natural Hazards》2022,111(2):2097-2115
Natural Hazards - Satellite based thermal anomaly occurs as a substantial precursor for strong earthquakes, as the need for earthquake precursor detection has very important for impending main... 相似文献
194.
Haji Abolhassani Amir Abbas Dimitrakopoulos Roussos Ferrie Frank P. Yao Lingqing 《Mathematical Geosciences》2022,54(6):1097-1119
Mathematical Geosciences - A new non-stationary, high-order sequential simulation method is presented herein, aiming to accommodate complex curvilinear patterns when modelling non-Gaussian,... 相似文献
195.
The world’s rising urban density expansion has resulted in a proliferation of attempts to efficiently use space and a higher level of spatial complexity in metropolitan areas. 3D geospatial data models are increasingly being embraced to facilitate communicating the spatial dimensions of complex built environments in different applications. For example, the use of 3D models in land administration systems has been recognized as a good approach for communicating the spatial complexity of legal spaces within multi‐storey buildings. The spatial extent of legal space—to which rights, restrictions and responsibilities relate in a 3D digital cadastre—needs to be accurately defined and geometrically closed; watertight. Therefore, this study aims to address the challenges regarding checking the closure of diverse 3D legal spaces and engage several techniques to formulate the watertight concept for cadastre. The research’s methodology is built on a 3D polyhedral surface using a half‐edge data structure. A primitive check is employed to assess the spatial consistency of lower‐dimensional primitives of 3D objects. Subsequently, advanced closure checks ensure the closure of volumetric legal spaces represented by 2‐manifold and non‐2‐manifold data models. The article concludes that, by adopting the proposed approaches, the internal spatial consistency of legal spaces in urban land administration will be certified. 相似文献
196.
Reduction the secular solution to periodic solution in the generalized restricted three-body problem
Elbaz I. Abouelmagd M. E. Awad E. M. A. Elzayat Ibrahim A. Abbas 《Astrophysics and Space Science》2014,350(2):495-505
The aim of the present work is to find the secular solution around the triangular equilibrium points and reduce it to the periodic solution in the frame work of the generalized restricted thee-body problem. This model is generalized in sense that both the primaries are oblate and radiating as well as the gravitational potential from a belt. We show that the linearized equation of motion of the infinitesimal body around the triangular equilibrium points has a secular solution when the value of mass ratio equals the critical mass value. Moreover, we reduce this solution to periodic solution, as well as some numerical and graphical investigations for the effects of the perturbed forces are introduced. This model can be used to examine the existence of a dust particle near the triangular points of an oblate and radiating binary stars system surrounded by a belt. 相似文献
197.
G. Abbas 《Astrophysics and Space Science》2014,352(2):955-961
This paper is devoted to study the effects of electromagnetic on the collapse and expansion of anisotropic gravitating source. For this purpose, we have evaluated the generating solutions of Einstein–Maxwell field equations with spherically symmetric anisotropic gravitating source. We found that a single function generates the various anisotropic solutions. In this case every generating function involves an arbitrary function of time which can be chosen to fit several astrophysical time profiles. Two physical phenomenon occur, one is gravitational collapse and other is the cosmological expanding solution. In both cases electromagnetic field effects the anisotropy of the model. For collapse the anisotropy is increased while for expansion it deceases from maximum value to finite positive value. In case of collapse there exits two horizons like in case of Reissner–Nordström metric. 相似文献
198.
This paper is devoted to study the geodesic structure of regular Hayward black hole. The timelike and null geodesics have been studied explicitly for radial and non-radial motion. For timelike and null geodesic in radial motion there exists analytical solution, while for non-radial motion the effective potential has been plotted, which investigates the position and turning points of the particle. It has been found that massive particle moving along timelike geodesics path are dragged towards the BH and continues to move around black hole in particular orbits. 相似文献
199.
Application of Large‐Scale Inversion Algorithms to Hydraulic Tomography in an Alluvial Aquifer 下载免费PDF全文
P. Fischer A. Jardani A. Soueid Ahmed M. Abbas X. Wang H. Jourde N. Lecoq 《Ground water》2017,55(2):208-218
Large‐scale inversion methods have been recently developed and permitted now to considerably reduce the computation time and memory needed for inversions of models with a large amount of parameters and data. In this work, we have applied a deterministic geostatistical inversion algorithm to a hydraulic tomography investigation conducted in an experimental field site situated within an alluvial aquifer in Southern France. This application aims to achieve a 2‐D large‐scale modeling of the spatial transmissivity distribution of the site. The inversion algorithm uses a quasi‐Newton iterative process based on a Bayesian approach. We compared the results obtained by using three different methodologies for sensitivity analysis: an adjoint‐state method, a finite‐difference method, and a principal component geostatistical approach (PCGA). The PCGA is a large‐scale adapted method which was developed for inversions with a large number of parameters by using an approximation of the covariance matrix, and by avoiding the calculation of the full Jacobian sensitivity matrix. We reconstructed high‐resolution transmissivity fields (composed of up to 25,600 cells) which generated good correlations between the measured and computed hydraulic heads. In particular, we show that, by combining the PCGA inversion method and the hydraulic tomography method, we are able to substantially reduce the computation time of the inversions, while still producing high‐quality inversion results as those obtained from the other sensitivity analysis methodologies. 相似文献
200.
Effects of Dietary Protein Level on Growth and Utilization of Protein and Energy by Juvenile Mangrove Red Snapper (Lutjanus argentimaculatus ) 总被引:1,自引:1,他引:0
1Introduction The mangrove red snapper,Lutjanus argentimacu-latus(Forsskal,1775)is a carnivorous,warm-watereuryhaline fish that is considerably cultured in South-east Asia,Southern China and the Middle East(Le-ung et al.,1999;Estudillo et at.,2000;Ng et al.,2000;Catacutan et al.,2001).In Pakistan,it isknown for its good quality meat and also for its highconsumption rate.Although it fetches a premiumprice at local markets(Anonymous,2002),the in-creasing demand has generated interest towar… 相似文献