• Communications for Statistical Applications and Methods
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• v.21 no.3
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• pp.225-234
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• 2014

We propose a novel hierarchical clustering for distribution valued dissimilarities. Analysis of large and complex data has attracted significant interest. Symbolic Data Analysis (SDA) was proposed by Diday in 1980's, which provides a new framework for statistical analysis. In SDA, we analyze an object with internal variation, including an interval, a histogram and a distribution, called a symbolic object. In the study, we focus on a cluster analysis for distribution valued dissimilarities, one of the symbolic objects. A hierarchical clustering has two steps in general: find out step and update step. In the find out step, we find the nearest pair of clusters. We extend it for distribution valued dissimilarities, introducing a measure on their order relations. In the update step, dissimilarities between clusters are redefined by mixture of distributions with a mixing ratio. We show an actual example of the proposed method and a simulation study.

• Journal of Korean Institute of Industrial Engineers
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• v.19 no.3
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• pp.113-121
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• 1993

The pressure distribution between body and seat surface has been considered as one of the most important factors which affect seation comfort. The pattern of body pressure distribution has been an index of measuring comfort of an automobile seat. There has been numerous studies that measured the body pressure distribution. But, studies have many problems(pressure distortion, resolution, reliability, portability, usability, and shape fitness) in measuring the body pressure distribution. In this study, the new body pressure distribution measuring equipment has been developed by using the thin, flat, and polymer-film devices known as Force Sensing Resistors(FSRs) in order to solve those problems.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.1677-1683
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• 2006

Color image segmentation is useful for fast retrieval in large image database. For that purpose, new image segmentation technique based on the probability of pixel distribution in the image is proposed. Color image is first divided into R, G, and B channel images. Then, pixel distribution from each of channel image is extracted to select to which it is similar among the well known probabilistic distribution function-Weibull, Exponential, Beta, Gamma, Normal, and Uniform. We use sum of least square error to measure of the quality how well an image is fitted to distribution. That P.d.f has minimum score in relation to sum of square error is chosen. Next, each image is quantized into 4 gray levels by applying thresholds to the c.d.f of the selected distribution of each channel. Finally, three quantized images are combined into one color image to obtain final segmentation result. To show the validity of the proposed method, experiments on some images are performed.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.383-384
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• 2015

DC system is still unexploited in public distribution systems. As the weight of cost efficiency and reliability requirements of distribution networks are expected to increase in the future, with the utilization of distributed generation, there will be demand for novel distribution techniques. The utilization of the Low Voltage DC (LVDC) distribution system opens new possibilities for network development. This paper presents analysis of steady state and transient state according to the number of pole in LVDC distribution system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.2
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• pp.231-238
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• 2011

A role of Distribution Automation System(DAS) is required to be changed from observing and control to complex and various new system including functions which monitoring, control, prediction, operation and management of EMS type according to be gradually Smart Grid of distribution operation system for development of further power system industrial. IEC(International Electrotechnical Commission) published communication standards which interface and data model of distribution operation system to IEC 61968 and of host system like EMS(Energy Management System) to IEC 61970. So far, each standards are emphasizing themselves, but if they are applied by designed integration of the standards, it could be more efficiency system. So, in this paper, integration application of IEC standards and structure of further distribution operation system to use them are proposed by gradually increasing importance of communication protocols, functions and roles in further distribution management system considering Smart Grid.

• Journal of Korean Society of Water and Wastewater
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• v.16 no.6
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• pp.726-732
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• 2002

Pressure drop could happen in the water distribution systems due to pipe breaks or maintenance. The pressure drop causes the water service shutdown and nodal water demands should be reduced in some areas. The conventional analysis method of water distribution systems can not consider the change of nodal water demands caused by these pressure drops. This study is to investigate the variation of nodal water demands according to the nodal water pressure and its effect on the analysis of water distribution systems. For these purpose, one real water service district was selected as a study area. As a result, nodal water demand patterns according to the water pressure could be suggested. Also, we could confirm that the suggested new analysis method for the water distribution systems which considering water pressure drops could be more reliable than the conventional method.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.273-280
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• 1999

The base shear and the veritcal distribution of shears along the height of a building are two fundamental measures that define the design seismic load. But the method specified in Korean building code does not give an appropriate distribution for buildings of tall or longer period because it roughly account for the contributions of the higher modes. several methods to give a better distribution of seismic forces have been proposed. But they have not been introduced into the seismic codes yet probably because they cannot solve all the above-mentioned problems. This paper deals with the distribution of lateral seismic forces along the height of a building to account for the contribution of the higher modes. After reviewing some existing distributions in seismic codes and literatures moment-resisting frames with various stories were studied by modal analysis for a wide range of fundamental period and the stiffness ratio of the buiding. As a result of the analysis a new expression for the distribution of seismic forces is proposed and compared with those of some codes and dynamic analysis.

• Wind and Structures
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• v.28 no.1
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• pp.63-70
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• 2019

Due to developing environmental concern use of renewable energy source is very essential. The great demand for the energy supply coupled with inadequate energy sources creates an emergency to find a new solution for the energy shortage. The appropriate wind energy distribution is the fundamental requirement for the assessment of wind energy potential available at the particular site essential for the design of wind farms. Hence the proper specification of the wind speed distribution plays a vital role. In this paper the Bimodal Weibull distribution is used to estimate the Capacity factor at the proposed site. The shape and scale parameters estimated using Maximum likelihood method is used as the initial value for extrapolation. Application of this model will give an accurate result overwhelming the concept of overestimation or underestimation of Capacity factor.

• Journal of Distribution Science
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• v.22 no.1
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• pp.61-67
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• 2024

Purpose: The study has identified factors affecting dynamic capabilities and the distribution of competitive advantage under the impact of dynamic capabilities of Vietnamese fintech businesses. Research design, data, and methods: The method used in this study is a survey analysis of 120 Vietnamese fintech businesses to test the hypothesized relationships of the research model as well as evaluate its effectiveness. The study uses the Cronbach alpha analysis, factor analyses, and structural equation modeling to assess the research's measurement and structural models. Results: Research results show that 3 critical success factors: "Capacity to develop financial service ideas," "Ability to develop a platform," and "Business capacity" have a positive impact on "Dynamic capabilities." In addition, the study also evaluates the effect of "dynamic capabilities" on the "competitive advantage" of fintech businesses. Conclusion: Theoretically, this result contributes to discovering new, specific factors affecting the dynamic capabilities of fintech businesses. In practice, the research results are empirical evidence of the distribution of competitive advantages of Vietnamese Fintech businesses and their impact on dynamic capabilities.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.4
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• pp.513-521
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• 2012

With the advent of smart grid, distribution network charges have been one of keystones of ongoing deregulation and privatization in power industries. This paper proposes a new charging methodology to allocate the existing distribution network cost with an aim of reflecting the true cost and benefit of network customers, especially of distribution generator (DG). The proposed charging methodology separates distribution network costs due to the respective real and reactive power flows. The costs are then allocated to network users according to each charge for the actual line capacity used and available capacity. This distribution network charging model is able to provide the economic signals to reward network users who are contributing to better power factors, while penalizing customers who worsen power factors. The proposed method is shown on IEEE 37 bus system for distribution network, and then the results are validated through the comparison with the MW-Miles and MVA-Miles methods. The charges derived from the proposed method can provide appropriate incentives/penalties to network customers to behave in a manner leading to a better network condition.