Iron ore is the main raw material of the production in iron and steel enterprises in China. It is a non-renewable resource and with limited reserves. In this paper, in combination with the practical situation of the m...
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Iron ore is the main raw material of the production in iron and steel enterprises in China. It is a non-renewable resource and with limited reserves. In this paper, in combination with the practical situation of the mine, an integer linear programming model of a strip mining block scheduling problem is established with the scientific, reasonable, and economical principle. The maximization of mining profit is set as the goal under the precedence constraints and production capacity constraints. This paper designs an improved particle swarm optimization algorithm to solve the problem and compares with results with CPLEX optimizing software. According to the results of different scale experiment, the improved particle swarm optimization algorithm has better performance.
This study was developed in the context of new challenges imposed by the recast of the Energy Performance of Buildings Directive 2010/31/EU (EPBD) and its supplementing regulation. The aim is to find the cost-optimal ...
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This study was developed in the context of new challenges imposed by the recast of the Energy Performance of Buildings Directive 2010/31/EU (EPBD) and its supplementing regulation. The aim is to find the cost-optimal level for the French single-family building typology, while providing an effective method to deal with a huge number of simulations corresponding to a large number of building configurations. The method combines the use of TRNSYS, dynamic energy simulation software, with GenOpt, Generic optimization program. The building that was taken as a reference is a real low-consumption house located in Amberieu-en-Bugey, Rhone-Alpes, France. The model was created and calibrated in TRNSYS and the energy efficiency measures, concerning different technologies for envelope systems and technical systems, were set up as parameters in GenOpt. After a research on the French market, a cost function was created for each parameter and the global cost function (EN15459 Standard) was taken as objective function for the optimization. The particle swarm optimization algorithm was used to minimize the objective function and find the cost-optimal building configuration within the current regulatory framework. (C) 2014 Elsevier B.V. All rights reserved.
In this work, a method for the single-objective optimization of material distribution of simply supported functionally graded isotropic plates is presented. The material composition is assumed to vary only in the thic...
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In this work, a method for the single-objective optimization of material distribution of simply supported functionally graded isotropic plates is presented. The material composition is assumed to vary only in the thickness direction. Piecewise cubic interpolation of volume fractions are used to calculate volume fractions of constituent material phases at a point;these fractions are defined at a limited number of evenly spaced control points. The effective material properties of the plate are obtained by applying linear rule of mixtures. Behavior of functionally graded plate is predicted by the assumptions of the third-order shear deformation theory of Reddy. Exact solutions for deflections and stresses of simply supported plates are presented by using Navier type solution technique. Those volume fractions at control points that are selected as decision variables are optimized by two evolutionary algorithms: (1) Real-coded genetic algorithm and (2) particle swarm optimization algorithm. Three models are optimized as primary goal to verify the capability and efficiency of the proposed model with flexibility and stress constraints under various transverse loads. Secondary goal of this article is survey accuracy and convergence of two algorithms aforementioned. The proposed framework for designing functionally graded plates under pure mechanical conditions has been furnished by the founded results. (C) 2013 Elsevier Ltd. All rights reserved.
By introducing the fractional-order difference into the updating formulas of the velocity and position,fractional-order particle swarm optimization algorithm is proposed. The effects on the convergence rate and accura...
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By introducing the fractional-order difference into the updating formulas of the velocity and position,fractional-order particle swarm optimization algorithm is proposed. The effects on the convergence rate and accuracy are analyzed, by introducing fractional-orders in the updating formulas for the velocity and position. Moreover, the linear increasing methods to adjust the fractional-orders are proposed. Compared with the standard particle swarm optimization algorithm, the higher convergence rate is achieving to improve the accuracy of the optimal result. Finally, five standard functions are tested, and the results of the numerical experiments illustrate the effectiveness of the fractional-order particleswarmoptimization
The transport line used in a terahertz FEL device has to transport electron beam through the entire system efficiently and meet the requirements of the beam parameters at the undulator entrance. Due to space limitatio...
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The transport line used in a terahertz FEL device has to transport electron beam through the entire system efficiently and meet the requirements of the beam parameters at the undulator entrance. Due to space limitations, the size of the magnets (five quadrupoles and two bending magnets) employed in the transport line was limited, and some devices were densely packed. In this paper, analyses of the effect of fringe fields and magnetic interference of magnets are presented. 3D models of these magnets are built and their linear optical properties are compared with those obtained by hard edge models. The results indicated that the effects of these factors are significant and they would cause a mismatch of the beam at the exit of the transport line under the preliminary lattice design. To solve this problem, the beam was re-matched using the particle swarm optimization algorithm. (C) 2014 Elsevier B.V. All rights reserved.
To ensure security during the excavation process of an earth pressure balance shield, this paper presents an optimal control method that accounts for the tunnel face's stability. The tunnel face is controlled by a...
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To ensure security during the excavation process of an earth pressure balance shield, this paper presents an optimal control method that accounts for the tunnel face's stability. The tunnel face is controlled by an optimal screw conveyor speed derived from the particle swarm optimization algorithm for a designed stable normal vector angle range on the distribution surface of the chamber pressure field. These normal vector angles can be computed online by measuring the changes to the earth pressure in the shield's chamber using a BP neural network model of the chamber pressure field distribution. An experimental example that uses excavation data from an actual EPB shield is given to illustrate the effectiveness of the proposed method. (C) 2014 Elsevier B.V. All rights reserved.
In this article, the numerical techniques are presented for the solution of Troesch's problem based on neural networks optimized with three different methods including particleswarmoptimization (PSO), active set...
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In this article, the numerical techniques are presented for the solution of Troesch's problem based on neural networks optimized with three different methods including particleswarmoptimization (PSO), active set (AS) and PSO hybridized with AS (PSO-AS) algorithms. The variable transformation is applied in order to convert the original problem to a transformed problem which is relatively less stiff to solve. Feed-forward artificial neural networks are used to model the transformed problem. Learning of adjustable parameters is made with PSO, AS and PSO-AS algorithms. The proposed methodologies are applied to a number of cases for stiff and non-stiff boundary value problems. The comparative analyses are carried out with other standard numerical solutions, as well as approximate analytical solver. (C) 2014 Elsevier Inc. All rights reserved.
This paper deals with a machine repair problem in which M identical operating machines are maintained by one server (repairman). The server is subject to breakdown and operates a threshold recovery policy. The thresho...
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This paper deals with a machine repair problem in which M identical operating machines are maintained by one server (repairman). The server is subject to breakdown and operates a threshold recovery policy. The threshold recovery policy means that when the server breaks down, the repair can be performed until q (1 <= q <= M) or more machines appear. The failure and service times of the machines, and the repair times of the server, are all assumed to be exponentially distributed. A cost model is developed to determine the optimal threshold value, optimal service rate and optimal repair rate. We then apply the particle swarm optimization algorithm to solve this optimization problem. Finally, some numerical examples are provided for illustrative purposes.
This paper presents a cuckoo search algorithm (CSA) based adaptive infinite impulse response (IIR) system identification scheme. The proposed scheme prevents the local minima problem encountered in conventional IIR mo...
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This paper presents a cuckoo search algorithm (CSA) based adaptive infinite impulse response (IIR) system identification scheme. The proposed scheme prevents the local minima problem encountered in conventional IIR modeling mechanisms. The performance of the new method has been compared with that obtained by other evolutionary computing algorithms like genetic algorithm (GA) and particleswarmoptimization (PSO). The superior system identification capability of the proposed scheme is evident from the results obtained through an exhaustive simulation study. (C) 2014 Elsevier Inc. All rights reserved.
Due to the crucial importance of the FACTS based damping controllers in mitigation the deteriorative impacts of the power system low frequency oscillations, particularly the inter-area modes, improving the system stab...
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Due to the crucial importance of the FACTS based damping controllers in mitigation the deteriorative impacts of the power system low frequency oscillations, particularly the inter-area modes, improving the system stability margins seems indispensible. This paper proposes an optimization approach to effectively carry out the multi-machine based stabilization function of the Gate-Controlled Series Capacitor (GCSC) in providing a robust damping to the power system low frequency oscillations. It is aimed to provide a reliable damping framework by means of an optimized GCSC based supplementary damping controller. Thus, to attain the most efficient set of the damping controller parameters, particle swarm optimization algorithm as a proficient optimum hunter is employed to explore for the global stabilization solution in accordance to a vast range of power system operating conditions. Moreover, as a weighty assessment, the eigenvalue analysis is taken into account as the cornerstone of the performed studies in order to investigate the damping methodology in which the unstable or lightly damped inter-area modes are scheduled to effectively shift to some predominant stability zones in the s-plane. Meanwhile, derived results through the nonlinear time domain simulation as well as two dynamic performance evaluators manifestly demonstrate the impressiveness and verify the robustness of the proposed GCSC based damping scheme in enhancing the power system stability, especially regarding to the inter-area modes. (C) 2013 Elsevier Ltd. All rights reserved.
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