Showing papers by "Zong Woo Geem published in 2011"
Journal Article•
TL;DR: The harmony search algorithm was applied to two test examples, and good Pareto solutions were obtained when compared with other algorithms, such as the genetic algorithm and the ant colony optimization algorithm.
91 citations
TL;DR: This study proposes a novel parameter-setting-free technique interfaced with a harmony search algorithm and applies it to the parameter estimation of the nonlinear Muskingum model, which is an optimization problem with continuous decision variables.
Abstract: Although phenomenon-mimicking algorithms, such as genetic algorithms, particle swarm optimization, and harmony search, have overcome the disadvantages of mathematical algorithms, such as the nonlinear least-squares method, segmented least-squares method, Lagrange multiplier method, a hybrid of pattern search and local search, and the Broyden-Fletcher-Goldfarb-Shanno technique, the algorithms have an inherent shortcoming. They require a tedious and skillful parameter-setting process for the algorithm parameters, such as the crossover rate, mutation rate, acceleration coefficients, harmony memory considering rate, and pitch-adjusting rate. Thus, this study proposes a novel parameter-setting-free technique interfaced with a harmony search algorithm and applies it to the parameter estimation of the nonlinear Muskingum model, which is an optimization problem with continuous decision variables. Results show that the proposed technique found good model parameter values while outperforming a classical harmony sea...
87 citations
TL;DR: In this paper, artificial neural network models were developed to forecast South Korea's transport energy demand, and several good models (Model 1 with GDP, population, and passenger transport amount; Model 2 with GDP and population, number of vehicle registrations and passenger transportation amount; and Model 3 with oil price, vehicle registration, and transport amount) were selected by comparing with multiple linear regression models.
59 citations
TL;DR: This study proposes a novel parameter-setting-free technique for two major algorithm parameters (HMCR and PAR) and combines it with the harmony search algorithm and reaches the global optimum with good results.
Abstract: Although phenomenon-mimicking or metaheuristic algorithms, such as genetic algorithm, simulated annealing, tabu search, shuffled frog-leaping algorithm, ant colony optimization algorithm, harmony search, cross entropy, scatter search, hybrid particle swarm optimization, and honeybee mating optimization, have overcome the disadvantages of gradient-based algorithms when optimally designing water distribution networks, those algorithms require the extra tedious task of algorithm parameter setting. This study proposes a novel parameter-setting-free technique for two major algorithm parameters (HMCR and PAR) and combines it with the harmony search algorithm. When the proposed model is applied to the optimal design of a popular benchmark problem, it reaches the global optimum with good results. Thus, the technique is expected to be used in the real-world design process under a more user-friendly environment.
51 citations
TL;DR: This study applied a gradient-based method, named generalized reduced gradient, and then obtains better results when compared with other approaches, when two additional approaches were introduced.
37 citations
01 Jan 2011
TL;DR: In this chapter, the optimum design problem of steel space frames is formulated according to the provisions of LRFD-AISC (Load and Resistance Factor Design-American Institute of Steel Corporation).
Abstract: Harmony search method is widely applied in structural design optimization since its emergence. These applications have shown that harmony search algorithm is robust, effective and reliable optimization method. Within recent years several enhancements are suggested to improve the performance of the algorithm. Among these Mahdavi has presented two versions of harmony search methods. He named these as improved harmony search method and global best harmony search method. Saka and Hasancebi (2009) have suggested adaptive harmony search where the harmony search parameters are adjusted automatically during design iterations. Coelho has proposed improved harmony search method. He suggested an expression for one of the parameters of standard harmony search method. In this chapter, the optimum design problem of steel space frames is formulated according to the provisions of LRFD-AISC (Load and Resistance Factor Design-American Institute of Steel Corporation). The weight of the steel frame is taken as the objective function to be minimized. Seven different structural optimization algorithms are developed each of which are based on one of the above mentioned versions of harmony search method. Three real size steel frames are designed using each of these algorithms. The optimum designs obtained by these techniques are compared and performance of each version is evaluated.
21 citations
01 Jan 2011
TL;DR: This study newly considers a more practical constraint (flow velocity range) that can avoid a critical problem of water hammer or pipe choking by sedimentation and is solved using a metaheuristic algorithm named harmony search.
Abstract: Water supply network is a key infrastructure in urban civilization and agricultural irrigation. In order to save the design cost of a network, which contains a nonlinear relationship between hydraulic energy loss and water flowrate, researchers have traditionally used mathematical optimization approaches. However, they have been more interested in meta-heuristic approaches recently because (1) these approaches directly provide commercial discrete diameters instead of impractical continuous ones; (2) they do not require complex gradient derivatives and free from divergence; (3) they do not require starting feasible vector and have more chance to find global optimum, etc. This study presents a new real-world example for the water network design, hoping to be a good literature. Furthermore, this study newly considers a more practical constraint (flow velocity range) that can avoid a critical problem of water hammer or pipe choking by sedimentation. Then, the numerical example is solved using a metaheuristic algorithm named harmony search, and the results are compared with those from a mathematical approach.
13 citations
TL;DR: The effect of using opposition-based learning and quadratic interpolation is investigated and three variants are proposed and the performance of these methods are compared with HS and other recent methods when applied to several benchmark functions.
Abstract: Harmony search (HS) is a recently spotlighted metaheuristic optimisation method imitating the music improvisation process where musicians improvise their instruments' pitches searching for a perfect state of harmony. In this paper, the effect of using opposition-based learning and quadratic interpolation is investigated. Three variants are proposed and the performance of these methods is investigated and compared with HS and other recent methods when applied to several benchmark functions. The experiments conducted show that the proposed methods generally outperformed the other methods when applied to the benchmark problems. Moreover, the performance of the proposed methods when applied to high-dimensional problems is investigated.
10 citations
9 citations
Book•
01 Apr 2011
TL;DR: This book introduces the common trajectory-driven and evolutionary-based ANN training algorithms.
Abstract: Artificial neural networks (ANN) are widely used in diverse fields of science and industry. Though there have been numerous techniques used for their implementations, the choice of a specific implementation is subjected to different factors including cost, accuracy, processing speed and overall performance. Featured with synaptic plasticity, the process of training is concerned with adjusting the individual weights between each of the individual ANN neurons until we can achieve close to the desired output. This book introduces the common trajectory-driven and evolutionary-based ANN training algorithms.
8 citations
TL;DR: The proposed stochastic co-derivative harmony search (CDHS) algorithm was applied to the design of hydraulic structure, and found better results than the original harmony search algorithm in terms of the number of reaching the global optimum and thenumber of function evaluations.
Abstract: A novel stochastic co-derivative was developed based on the density information of multiple vectors in the harmony search (HS) algorithm. While the existing stochastic partial derivative represents the probability with which certain candidate value is selected when searching for a new vector, this co-derivative represents how much one variable in a vector is correlated with other variables. The proposed stochastic co-derivative harmony search (CDHS) algorithm was applied to the design of hydraulic structure, and found better results than the original harmony search algorithm in terms of the number of reaching the global optimum and the number of function evaluations. The algorithm was also tested with a bigger hydraulic problem, finding better solutions in terms of least and average costs when compared with other phenomenon-mimicking algorithms such as genetic algorithm (GA), simulated annealing (SA), and tabu search (TS).
TL;DR: This study proposed a slightly better formula than the original one in terms of root-mean-square error and determination coefficient for calculating the through-flow velocity.
Abstract: A dam is a useful structure for human society, but does harm to wildlife such as migratory fish. Thus, in order to conserve fish habitat, fish passage can be constructed. For designing a nature-like fishway, through-flow velocity, which is defined as the average velocity over water flow through rock voids, can be a critical design factor. This study tries to propose a better formula in calculating the through-flow velocity. Based on 19 experimental data, this study proposed a slightly better formula than the original one in terms of root-mean-square error and determination coefficient.