• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.345-350
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• 1999

The effectiveness of software error compensation for thermally induced machine tool errors relies on the prediction accuracy of the pre-established thermal error models. The selection of optimal sensor locations is the most important in establishing these empirical models. In this paper, a methodology for the selection of optimal sensor locations is proposed to establish a robust linear model which is not subjected to collinearity. Correlation coefficient and time delay are used as thermal parameters for optimal sensor location. Firstly, thermal deformation and temperatures are measured with machine tools being excited by sinusoidal heat input. And then, after correlation coefficient and time delays are calculated from the measured data, the optimal sensor location is selected through hard c-means clustering and sequential selection method. The validity of the proposed methodology is verified through the estimation of thermal expansion along Z-axis by spindle rotation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.4
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• pp.551-559
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• 2008

Increase in power consumption can cause a serious stability problem of an electric power system without construction of new power plants or transmission lines. Also, it can generate large power loss of the system. In costly and environmentally effective manner to avoid constructing the new infrastructures such as power plants and transmission lines, etc, the distributed generation(DG) has paid great attentions so far as a solution for the above problem. Selection of optimal location and size of the DG is the necessary process to maintain the stability and reliability of existing system effectively. However, the systematic and cardinal rule for this issue is still open question. In this paper, the method to determine optimal location of the DG is proposed by considering power loss when the DG is connected to an electric power grid. Also, optimal size of not only the corresponding single DG but also the multi-DGs is determined with the proposed systematic approach. The IEEE benchmark 30-bus test system is analyzed to evaluate the feasibility and effectiveness of the proposed method.

• Journal of Navigation and Port Research
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• v.34 no.1
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• pp.59-64
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• 2010

This study is to determine an optimal marina's construction location candidate among many alternative candidates in order to obtain the maximized efficiency under the natural conditions. To deal with marina's construction location, the optimal construction location is selected using 10 important factor analysis for 10 candidates in Yeosu city. In this paper, the new model to assign the most reasonable alternative is introduced using 0-1 integer programming. This proposed model has not been applied in the optimal marina's facility candidate selection problem yet. This paper will contribute to determine the most reasonable alternative. Also, this proposal model can be applied to other marina's facility candidate selection problem in other regions.

• Journal of KIBIM
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• v.12 no.2
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• pp.1-11
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• 2022

Road traffic accidents (RTAs) are the leading cause of accidental death among children. RTA reduction is becoming an increasingly important social issue among children. Municipalities aim to resolve this issue by introducing "Smart Pedestrian Crosswalks" that help prevent traffic accidents near children's facilities. Nonetheless such facilities tend to be installed in relatively limited number of areas, such as the school zone. In order for budget allocation to be efficient and policy effects maximized, optimal location selection based on machine learning is needed. In this paper, we employ machine learning models to select the optimal locations for smart pedestrian crosswalks to reduce the RTAs of children. This study develops an optimal location index using variable importance measures. By using k-means clustering method, the authors classified the crosswalks into three types after the optimal location selection. This study has broadened the scope of research in relation to smart crosswalks and traffic safety. Also, the study serves as a unique contribution by integrating policy design decisions based on public and open data.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.12
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• pp.4776-4798
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• 2015

The location selection of virtual machines in distributed cloud is difficult because of the physical resource distribution, allocation of multi-dimensional resources, and resource unit cost. In this study, we propose a multi-object virtual machine location selection algorithm (MOVMLSA) based on group information, doubly linked list structure and genetic algorithm. On the basis of the collaboration of multi-dimensional resources, a fitness function is designed using fuzzy logic control parameters, which can be used to optimize search space solutions. In the location selection process, an orderly information code based on group and resource information can be generated by adopting the memory mechanism of biological immune systems. This approach, along with the dominant elite strategy, enables the updating of the population. The tournament selection method is used to optimize the operator mechanisms of the single-point crossover and X-point mutation during the population selection. Such a method can be used to obtain an optimal solution for the rapid location selection of virtual machines. Experimental results show that the proposed algorithm is effective in reducing the number of used physical machines and in improving the resource utilization of physical machines. The algorithm improves the utilization degree of multi-dimensional resource synergy and reduces the comprehensive unit cost of resources.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1587-1596
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• 2020

The location selection for nuclear power plants (NPP) is a strategic decision, which has significant impact operation of the plant and sustainable development of the region. Further, the ranking of the alternative locations and selection of the most suitable and efficient locations for NPPs is an important multi-criteria decision-making problem. In this paper, the non-sequential Monte Carlo probabilistic method and the Latin hypercube sampling probabilistic method are used to evaluate and select the optimal locations for NPP. These locations are identified by the power plant's onsite loads and the average of the lowest number of relay protection after the NPP's trip, based on electricity considerations. The results obtained from the proposed method indicate that in selecting the optimal location for an NPP after a power plant trip with the purpose of internal onsite loads of the power plant and the average of the lowest number of relay protection power system, on the IEEE RTS 24-bus system network given. This paper provides an effective and systematic study of the decision-making process for evaluating and selecting optimal locations for an NPP.

• Journal of Navigation and Port Research
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• v.33 no.4
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• pp.271-275
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• 2009

A strategic decision making on location selection for product transportation includes many tangible and untangible factors. To choose the best locations is a difficult job in the sense that objectives usually conflict with each other. In this paper, we consider a multi stage multi criteria transshipment problem with different types of items to be transported from the sources to the destination points. For the optimization of the problem, a goal programming formulation will be presented in which the location selection for each product type will be determined under the multi objective criteria. In the study, we generalize the transshipment model with a variety of product types and finite number of different intermediate nodes between origins and destinations. For the selection of the criteria we selected the costs(fixed cost and transportation cost), location numbers, and unsatisfied demand for each type of products in multi stage transportation, which are the main goals in transshipment modelling problems. The related conditions are also modelled through linear formats.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1063-1065
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• 1998

This paper discusses the selection of optimal location of Thyristor Controlled Series Compensator (TCSC) devices to maintain the steady-state voltage profile within limits. A procedure for selecting optimal TCSC location based on sensitivity analysis is developed. This approach identifies the critical lines by evaluating all the voltage magnitudes sensitivity with respect to a line reactance. Computer simulation of a example system is used to verify the proposed procedure.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.4
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• pp.323-329
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• 2011

This study is to determine an optimal yacht mooring location candidate among many alternative candidates in order to obtain the maximized efficiency under the natural conditions using integer programming. To deal with marina's construction location, the optimal construction location is selected using 21 important factors analysis for 4 candidates in the Mokpo city. The development period and the initial investment cost weight are one and half times more than the others among 21 factors. The optimal spiral analysis of weighted linear model shows that the Peace Square sea area is selected as the most optimal place among 4 candidates. This proposed model has not been applied in the optimal marina's facility candidate selection problem yet. This paper will contribute to determine the most reasonable alternative. Also, this proposal model can be applied to other marina's facility candidate selection problem in other regions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.676-682
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• 2017

The purpose of this study is to suggest the elements that need to be taken into consideration in urban planning to determine the optimal location of education and research facilities based on the knowledge-based industry in a large Korean city. In this study, we conducted an analysis and evaluation of the locational conditions and elements of education and research facilities as the important functions for regional economic revitalization and urban balance development. For this purpose, the relevant concepts and patterns of education and research facilities were reviewed as a theoretical research endeavor, and their locational conditions and elements were surveyed based on the existing research. The planning directions and some lessons for determining the location of the facilities are suggested through the analysis of the evaluation method according to the selection of the location. The results of this study are expected to act as guidelines for the optimal location selection of education and research facilities in large Korean cities in the era of the fourth industrial revolution.