Current Status of Marine Pollution and Mitigation Strategies in Arid Region: A Detailed Review     

Chitrakar  Prerana  Baawain  Mahad Said  Sana  Ahmad  Al-Mamun  Abdullah 《Ocean Science Journal》2019,54(3):317-348

Ocean Science Journal - Coastal pollution is becoming a significant threat for both marine ecosystems and humans. Marine pollution and coastal degradation are severely exacerbated by anthropogenic...  相似文献   

Structural vibration reduction using self-tuning fuzzy control of magnetorheological dampers     

Claudia Mara Dias Wilson  Makola M. Abdullah 《Bulletin of Earthquake Engineering》2010,8(4):1037-1054

Among the control devices considered for dissipating seismic energy and reducing structural vibrations is the magnetorheological (MR) damper which consists of a hydraulic cylinder filled with a suspension of micron-sized, magnetically polarizable iron particles capable of reversibly changing from free-flowing, linear viscous fluid to semi-solid with the application of a magnetic field. Several algorithms have been proposed for regulating the amount of damping provided by MR dampers. An attractive option is the use of fuzzy controllers because they are simple, intrinsically robust, and they do not depend on a model of the system. Tuning of these controllers, however, has shown to be a difficult task because of the large number of parameters involved. This paper proposes a self-tuning fuzzy controller to regulate MR dampers’ properties and reduce structural responses of single degree-of-freedom seismically excited structures. Robustness to changes in seismic motions and structural characteristics was assessed by subjecting a rigid and a flexible building to different earthquake records. Results show that the self-tuning controller proposed effectively reduced responses of both structures to all earthquakes considered. In addition, results were compared to those of a fuzzy controller with constant scaling factors and to those of two passive strategies: “passive on” and “passive off”, where the current to the MR dampers was set to its maximum allowable value, and zero, respectively.  相似文献   

Lithospheric structure of the Arabian Shield and Platform from complete regional waveform modelling and surface wave group velocities     

Arthur J. Rodgers  William R. Walter  Robert J. Mellors  Abdullah M. S. Al-Amri  & Yu-Shen Zhang 《Geophysical Journal International》1999,138(3):871-878

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Toward a ground-motion logic tree for probabilistic seismic hazard assessment in Europe   总被引：9，自引：2，他引：7  

Elise Delavaud  Fabrice Cotton  Sinan Akkar  Frank Scherbaum  Laurentiu Danciu  Céline Beauval  Stéphane Drouet  John Douglas  Roberto Basili  M. Abdullah Sandikkaya  Margaret Segou  Ezio Faccioli  Nikos Theodoulidis 《Journal of Seismology》2012,16(3):451-473

The Seismic Hazard Harmonization in Europe (SHARE) project, which began in June 2009, aims at establishing new standards for probabilistic seismic hazard assessment in the Euro-Mediterranean region. In this context, a logic tree for ground-motion prediction in Europe has been constructed. Ground-motion prediction equations (GMPEs) and weights have been determined so that the logic tree captures epistemic uncertainty in ground-motion prediction for six different tectonic regimes in Europe. Here we present the strategy that we adopted to build such a logic tree. This strategy has the particularity of combining two complementary and independent approaches: expert judgment and data testing. A set of six experts was asked to weight pre-selected GMPEs while the ability of these GMPEs to predict available data was evaluated with the method of Scherbaum et al. (Bull Seismol Soc Am 99:3234?C3247, 2009). Results of both approaches were taken into account to commonly select the smallest set of GMPEs to capture the uncertainty in ground-motion prediction in Europe. For stable continental regions, two models, both from eastern North America, have been selected for shields, and three GMPEs from active shallow crustal regions have been added for continental crust. For subduction zones, four models, all non-European, have been chosen. Finally, for active shallow crustal regions, we selected four models, each of them from a different host region but only two of them were kept for long periods. In most cases, a common agreement has been also reached for the weights. In case of divergence, a sensitivity analysis of the weights on the seismic hazard has been conducted, showing that once the GMPEs have been selected, the associated set of weights has a smaller influence on the hazard.  相似文献   

Adaptive neuro-fuzzy evaluation of wind farm power production as function of wind speed and direction   总被引：1，自引：1，他引：0  

Dalibor Petković  Shahaboddin Shamshirband  Nor Badrul Anuar  Sareh Naji  Miss Laiha Mat Kiah  Abdullah Gani 《Stochastic Environmental Research and Risk Assessment (SERRA)》2015,29(3):793-802

Wind velocity assumes a critical part for measuring the power created by the wind turbines. Nonetheless, power production from wind has a few weaknesses. One significant issue is that wind is a discontinuous energy source which implies that there exists substantial variability in the generation of vigor because of different variables, for example, wind speed. Wind direction is a significant variable for proficient turbine control for getting the most energy with a given wind speed. Taking into account the conjectures on wind heading, it might be conceivable to adjust the turbine to the wind bearing to get the most energy yield. Since both forecasts of wind speed and direction are basic for effective wind energy collecting it is crucial to develop a methodology for estimation of wind speed and direction and afterwards to estimate wind farm power production as function of wind pace and heading distribution. Despite the fact that various numerical functions have been proposed for demonstrating the wind speed and direction frequency distribution, there are still disadvantages of the models like very demanding in terms of calculation time. In this investigation adaptive neuro-fuzzy inference system (ANFIS), which is a particular sort of the artificial neural networks (ANN) family, was used to anticipate the wind speed and direction frequency dispersion. Thereafter, the ANFIS system was utilized to gauge wind homestead power creation as function of wind velocity and bearing. Neural system in ANFIS modifies parameters of enrollment capacity in the fuzzy logic of the fuzzy inference system. The reenactment outcomes exhibited in this paper demonstrate the adequacy of the created technique.  相似文献   

A clustering model based on an evolutionary algorithm for better energy use in crop production     

Benyamin Khoshnevisan  Elham Bolandnazar  Sasan Barak  Shahaboddin Shamshirband  Hamid Maghsoudlou  Torki A. Altameem  Abdullah Gani 《Stochastic Environmental Research and Risk Assessment (SERRA)》2015,29(8):1921-1935

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Seasonal Shift in Community Structure of Periphytic Ciliates in Estuarine Waters in the Northern Bay of Bengal,Bangladesh     

Mamun?Abdullah Al  Rahman?Muhammed?Forruq  Aysha?Akhtar  Md.?Wahidul?Alam  Mohammad?Nurul?Azim?Sikder  Alan?Warren  Henglong?XuEmail author 《Ocean Science Journal》2018,53(4):707-718

To investigate the seasonal heterogeneity of the periphytic ciliate communities, a 1-year baseline survey was conducted in the Karnaphuli River estuary, northern Bay of Bengal, Bangladesh. A total of 54 ciliate species were recorded, including seven common and 14 dominant species. Maximum species number was in autumn whereas maximum abundance was in winter; the minimum for both occurred in summer. Multivariate analyses, i.e., canonical analysis of principal coordinates (CAP) and principal co-ordinates analysis (PCoA), revealed a clear seasonal heterogeneity of community structure and environmental variables. Multivariate correlation analysis (RELATE) demonstrated that the community structure of the periphytic ciliate communities was significantly correlated with environmental variables, and best matching analysis (BIOENV) indicated that heterogeneity of community patterns was mainly driven by water temperature, pH, dissolved oxygen, total dissolved solids and nutrients. Species richness and diversity peaked in autumn whereas species evenness peaked in summer. These results suggest that environmental conditions shape periphytic ciliate community structure, which is a potentially useful bio-indicator of estuarine water quality.  相似文献   

Circular restricted three-body problem when both the primaries are heterogeneous spheroid of three layers and infinitesimal body varies its mass     

Abdullah A. Ansari  Ziyad Ali Alhussain  Sada Nand Prasad 《Journal of Astrophysics and Astronomy》2018,39(5):57

The circular restricted three-body problem, where two primaries are taken as heterogeneous oblate spheroid with three layers of different densities and infinitesimal body varies its mass according to the Jeans law, has been studied. The system of equations of motion have been evaluated by using the Jeans law and hence the Jacobi integral has been determined. With the help of system of equations of motion, we have plotted the equilibrium points in different planes (in-plane and out-of planes), zero velocity curves, regions of possible motion, surfaces (zero-velocity surfaces with projections and Poincaré surfaces of section) and the basins of convergence with the variation of mass parameter. Finally, we have examined the stability of the equilibrium points with the help of Meshcherskii space–time inverse transformation of the above said model and revealed that all the equilibrium points are unstable.  相似文献   

Generalized Elliptic Restricted Four-Body Problem with Variable Mass     

Ansari  Abdullah A.  Prasad  Sada Nand 《Astronomy Letters》2020,46(4):275-288

Astronomy Letters - The elliptic case of restricted four-body problem with variable mass of infinitesimal body is studied here. The three primary bodies which are placed at the vertices of an...  相似文献   

Hydrocarbon Generation Potential of the Organic-Rich Naifa Formation,Say’un–Masila Rift Basin,Yemen: Insights from Geochemical and Palynofacies Analyses     

Hakimi  Mohammed Hail  Abdullah  Wan Hasiah  Lashin  Aref A.  Ibrahim  El-Khedr H.  Makeen  Yousif M. 《Natural Resources Research》2020,29(4):2687-2715

Natural Resources Research - The Say’un–Masila rift, one of the most important basins of Yemen, contains unconventional resources of organic-rich rocks. In the present work, geochemical...  相似文献