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Razavi Khorasan, Iran

Giustolisi O.,University of Bari | Moosavian N.,University of Torbat-e-Heydarieh
Journal of Hydroinformatics | Year: 2014

Steady-state Water Distribution Network models compute pipe flows and nodal heads for assumed nodal demands, pipe hydraulic resistances, etc. The nonlinear mathematical problem is based on energy and mass conservation laws which is solved by using global linearization techniques, such as global gradient algorithm (GGA). The matrix of coefficients of the linear system inside GGA belongs to the class of sparse, symmetric and positive definite. Therefore a fast solver for the linear system is important in order to achieve the computational efficiency, especially when multiple runs are required. This work aims at testing three main strategies for the solution of linear systems inside GGA. The tests are performed on eight real networks by sampling nodal demands, considering the pressure-driven and demand-driven modelling to evaluate the robustness of solvers. The results show that there exists a robust specialized direct method which is superior to all the other alternatives. Furthermore, it is found that the number of times the linear system is solved inside the GGA does not depend on the specific solver, if a small regularization to the linear problem is applied, and that pressure-driven modelling requires a greater number which depends on the size and topology of the network and not only on the level of pressure deficiency. © IWA Publishing 2014. Source


Mohaghegh M.R.,University of Torbat-e-Heydarieh
International Review of Mechanical Engineering | Year: 2011

Forced and free convection heat transfer phenomena are similar in some aspects, but governed by different equations and correlations. While the forced convection over a wedge is governed by the Flakner-Skan equation where momentum equation independent of energy equations, while in the free convection these equations are dependent on each other and must be solved simultaneously. This paper analyses natural convection heat transfer mechanism on an isothermal vertical flat plat and forced convection over a Wedge, through solving the similarity of governing equations. Boundary layer formed on the plate and wedge is a laminar. Numerical techniques applied in this work are fourth order Runge-Kutta method for ordinary differential equations solution and shooting method for boundary conditions. © 2011 Praise Worthy Prize S.r.l.- All rights reserved. Source


Moosavian N.,University of Torbat-e-Heydarieh
Swarm and Evolutionary Computation | Year: 2015

Soccer league competition (SLC) algorithm, is a new meta-heuristic optimization technique and has been successfully used to tackle the optimization problems in discrete or continuous space. Fundamental ideas of SLC are inspired by a professional soccer leagues and based on the competitions among teams and players. Population individuals or players are in two types: fixed players and substitutes that all together form some teams. The competition among teams to take the possession of the top ranked positions in the league table and the internal competitions between players in each team for personal improvements are used for simulation purpose and convergence of the population individuals to the global optimum. In this study, an enhanced SLC algorithm is proposed to solve knapsack problems effectively. This new version is free and independent from adjusting the parameters. The experimental results on the some benchmark knapsack problems demonstrate that the proposed SLC is efficient and effective, which outperforms the other algorithms, in terms of the search accuracy, reliability and convergence speed. © 2014 Elsevier B.V. All rights reserved. Source


Motallebzadeh K.,University of Torbat-e-Heydarieh | Kafi Z.,University of Torbat-e-Heydarieh
International Journal of Applied Linguistics and English Literature | Year: 2015

The present study aimed at investigating the possible significant effects of project-based instruction on the improvement of Iranian intermediate EFL learners’ awareness of 21st century skills. To this end, the sample population was selected from Iranian intermediate learners studying at Zabansara Language School, Mashhad, Iran. Therefore, 50 male and female students were assigned randomly to experimental and control groups, 25 in each. For collecting the quantitative data for the study, a 21st century awareness inventory was employed to function as the pre and post-tests during the study with the aim of eliciting the learners’ awareness of the aforementioned skills. Besides, a structured interview was applied within the participants of the experimental group to gather the required qualitative data by the time the treatment and the post-test were done. Regarding the treatment, a more real life class project was employed by the researchers containing some of the aims and principles of Place-Based Education, the model of the present study. Results showed that students in the experimental group could perform much better than learners in the control group after the treatment on the post-test. © Australian International Academic Centre, Australia. Source


Moosavian N.,University of Torbat-e-Heydarieh | Kasaee Roodsari B.,Syracuse University
Swarm and Evolutionary Computation | Year: 2014

Water distribution networks are one of the most important elements in the urban infrastructure system and require huge investment for construction. Optimal design of water systems is classified as a large combinatorial discrete non-linear optimization problem. The main concern associated with optimization of water distribution networks is related to the nonlinearity of discharge-head loss equation, availability of the discrete nature of pipe sizes, and constraints, such as conservation of mass and energy equations. This paper introduces an efficient technique, entitled Soccer League Competition (SLC) algorithm, which yields optimal solutions for design of water distribution networks. Fundamental theories of the method are inspired from soccer leagues and based on the competitions among teams and players. Like other meta-heuristic methods, the proposed technique starts with an initial population. Population individuals (players) are in two types: fixed players and substitutes that all together form some teams. The competition among teams to take the possession of the top ranked positions in the league table and the internal competitions between players in each team for personal improvements are used for simulation purpose and convergence of the population individuals to the global optimum. Results of applying the proposed algorithm in three benchmark pipe networks show that SLC converges to the global optimum more reliably and rapidly in comparison with other meta-heuristic methods. © 2014 Elsevier B.V. Source

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