• Journal of Power System Engineering
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• v.22 no.6
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• pp.20-27
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• 2018

Vessel maneuvering problem in the harbor area is generating considerable interests in terms of marine cybernetics. In this sense, the vessel is operated and moves at ultimately low or zero speed in shallow water area. So the vessel is usually aided by the cooperation with thrusters, main propulsion system, tugboats and pilots, etc. In this paper, we suggest a new vessel berthing technique using dampers and winches as a solution for excessively complicate and dangerous berthing work. In the proposed berthing method, in order to manipulate the actuators (winches and dampers), a simple and heuristic control strategy is applied for a basic experiment. Finally, experiments are conducted to verify the effectiveness of the proposed automatic vessel berthing strategy based on the heuristic control method.

• Smart Structures and Systems
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• v.20 no.5
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• pp.607-618
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• 2017

In this research, a newly developed nature-inspired optimization method, the Lion Pride Optimization algorithm (LPOA), is utilized for optimal design of composite steel box girder bridges. A composite box girder bridge is one of the common types of bridges used for medium spans due to their economic, aesthetic, and structural benefits. The aim of the present optimization procedure is to provide a feasible set of design variables in order to minimize the weight of the steel trapezoidal box girders. The solution space is delimited by different types of design constraints specified by the American Association of State Highway and Transportation Officials. Additionally, the optimal solution obtained by LPOA is compared to the results of other well-established meta-heuristic algorithms, namely Gray Wolf Optimization (GWO), Ant Lion Optimizer (ALO) and the results of former researches. By this comparison the capability of the LPOA in optimal design of composite steel box girder bridges is demonstrated.

• Structural Engineering and Mechanics
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• v.58 no.3
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• pp.533-553
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• 2016

In this paper, the recently developed meta-heuristic algorithm called tug of war optimization is applied to optimal design of castellated beams. Two common types of laterally supported castellated beams are considered as design problems: beams with hexagonal openings and beams with circular openings. Here, castellated beams have been studied for two cases: beams without filled holes and beams with end-filled holes. Also, tug of war optimization algorithm is utilized for obtaining the solution of these design problems. For this purpose, the minimum cost is taken as the objective function, and some benchmark problems are solved from literature.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.2
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• pp.185-197
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• 1998

Engineering design involves the specification of many variables that define a product, how it is made, and how it behaves. Before some variables can be determined, other variables must first be known or assumed. This fact implies a precedence order of the variables, and of the tasks of determining these variable consequently. Moreover, design of complex systems may involve a large number of design activities. In this paper, the activity-activity incidence matrix is considered as a representation of design activity analysis which mainly focuses on the precedence constraint. In order to analyze the activity-activity incidence matrix, a heuristic algorithm is proposed, which transforms an activity-activity, parameter-formula, and parameter-parameter incidence matrix into a lower triangular form. The analysis of the structured matrices can not only significantly reduce the overall project complexity by reorganizing few critical tasks in practice, but also aims at obtaining shorter times considering the solution structure by exploring concurrency.

• Steel and Composite Structures
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• v.8 no.6
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• pp.475-490
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• 2008

A hybrid tabu-simulated annealing algorithm is proposed for the optimum design of steel frames. The special character of the hybrid algorithm is that it exploits both tabu search and simulated annealing algorithms simultaneously to obtain near optimum. The objective of optimum design problem is to minimize the weight of steel frames under the actual design constraints of AISC-LRFD specification. The performance and reliability of the hybrid algorithm were compared with other algorithms such as tabu search, simulated annealing and genetic algorithm using benchmark examples. The comparisons showed that the hybrid algorithm results in lighter structures for the presented examples.

• Structural Engineering and Mechanics
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• v.65 no.6
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• pp.707-719
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• 2018

In this article, a new method is introduced to improve the local search capability of meta-heuristic algorithms using the projection of the path on the border of constraints. In a mathematical point of view, the Gradient Projection Method is applied through a new approach, while the imposed limitations are removed. Accordingly, the gradient vector is replaced with a new meta-heuristic based vector. Besides, the active constraint identification algorithm, and the projection method are changed into less complex approaches. As a result, if a constraint is violated by an agent, a new path will be suggested to correct the direction of the agent's movement. The presented procedure includes three main steps: (1) the identification of the active constraint, (2) the neighboring point determination, and (3) the new direction and step length. Moreover, this method can be applied to some meta-heuristic algorithms. It increases the chance of convergence in the final phase of the search process, especially when the number of the violations of the constraints increases. The method is applied jointly with the authors' newly developed meta-heuristic algorithm, entitled Star Graph. The capability of the resulted hybrid method is examined using the optimal design of truss and frame structures. Eventually, the comparison of the results with other meta-heuristics of the literature shows that the hybrid method is successful in the global as well as local search.

• Journal of Distribution Science
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• v.15 no.9
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• pp.53-62
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• 2017

Purpose - This study aims to analyze the effects of preference for Korean Wave and heuristic on shopping satisfaction and switching barriers of Chinese people visiting Korea, and also their positive effects on consumers' behavioral intention with these variables as mediating variables by using the structural equation model. Research design, data, and Methodology - For this study, we collected 264 questionnaires of Chinese consumers' who have experienced tourism and shopping in Korea after excluding questionnaires that were not proper to be analyzed. The residence of Chinese visiter was Shandong Province, Beijing, Shanghai, Shenyang. The data of this study was analyzed using SPSS 23 statistics to verify the reliability and discriminant validity. Structural equation method was used to test the hypotheses in this study. Results - The effects of heuristic variable on shopping satisfaction and the switching barriers variable were statistically significant. The effects variables of Korean Wave effect variable were statistically significant only on the switching barriers variable. However, the Korean Wave effect variable did not have a statistically significant effect on the shopping satisfaction. Conclusions - The shopping satisfaction and Korean Wave effect variables had statistically significant effects on the behavioral intention variable. In the result of indirect analysis, only the heuristic effect had indirect effects on consumers' behavior intention.

• Journal of Korea Game Society
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• v.9 no.1
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• pp.63-74
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• 2009

This paper mainly focused on research developing online game characteristic evaluation system based on game characteristic evaluation model design. Online game characteristic evaluation system is a system that evaluates game online in real-time using evaluation elements defined by model design. Game characteristic evaluation system uses heuristic evaluation method, which is used to execute evaluation in four parts, technical element, manage element, social element, and competitive element. To verify objectivity and validity of game characteristic evaluation, assessment was performed by three groups of beginners, intermediates, and professionals to increase the trust. And game characteristic evaluation forum was hosted to collect opinion from diverse classes.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.33 no.12
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• pp.53-62
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• 2017

Many gradient-based mathematical methods have been developed and are in use for structural size optimization problems, in which the cross-sectional areas or sizing variables are usually assumed to be continuous. In most practical structural engineering design problems, however, the design variables are discrete. The main objective of this paper is to propose an efficient optimization method for structures with discrete-sized variables based on the harmony search (HS) meta-heuristic algorithm that is derived using penalty function. The recently developed HS algorithm was conceptualized using the musical process of searching for a perfect state of harmony. It uses a stochastic random search instead of a gradient search so that derivative information is unnecessary. In this paper, a discrete search strategy using the HS algorithm with a static penalty function is presented in detail and its applicability using several standard truss examples is discussed. The numerical results reveal that the HS algorithm with the static penalty function proposed in this study is a powerful search and design optimization technique for structures with discrete-sized members.

• The Journal of Economics, Marketing and Management
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• v.11 no.5
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• pp.69-80
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• 2023

Purpose: The purpose of this study is to identify factors that affect decision-making for e-commerce users and to present ecommerce companies with the company's strategic directions for consumer purchases. Research design, data, and methodology: In this study, a structured research model was derived to confirm the relationship between brand image, product liking, heuristic and purchase intention and the difference according to psychological power. For analysis a total of 212 valid questionnaires from e-commerce users were used. confirmatory factor analysis, correlation analysis, and structural equations were conducted to verify. Results: Both brand image and product liking had a significant effect on purchase intention as well as heuristics. However, heuristics did not affect the purchase intention. It was found that the relationship between brand image, product liking, heuristic, and purchase intention differed depending on the psychological power. Conclusions: Companies should seek ways to increase the positive brand image and likability of products so that consumers can quickly purchase products. In the relationship between brand image and heuristic, the low-psychological group has more influence on heuristic, and in case of product liking, the high-psychological group has more influence on heuristic. In the relationship between brand image and product liking for purchase intention, both in the high psychological power group affect more influence on purchase intention. Since the process of purchasing products varies depending on the consumer psychological power tendency, it is necessary to identify the characteristics of consumers and establish strategies for purchasing promotion measures.