• Journal of Distribution Science
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• v.13 no.3
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• pp.5-9
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• 2015

Purpose -The purpose of this study was to review and analyze the four major journals of KODISA and all of their published articles of 2014 and to revise and update the existing publication standards and practices in order to improve the overall quality and reputation of these journals. Research design, data, and methodology - This study applied an analytical approach, a case study method, to analyze and examine the published articles and the publication standards and practices of four KODISA journals, JDS (1999), IJIDB (2010), EAJBM (2011), and JAFEB (2014), from their first publication. Results - In 2014, KODISA journals published a total of 171 papers - JDS (122), IJIDB and EAJBM (16 each), and JAFEB (17): 94 articles in general business and 77 articles in economics. Conclusions - KODISA journals continuously revised and updated their publication standards and practices and adopted technological support systems to enable its journals to remain independent and open access in order to ultimately become one of the world's reputable journals.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.215-222
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• 2013

Electrical power distribution systems are critical links between the utility and customer. In general, power distribution systems have unbalanced feeders due to the unbalanced loading. The devices that dependent on balanced three phase supply are affected by the unbalanced feeders. This necessitates the balancing of feeders. The main objective of reconfiguration is to balance the loads among the phases subject to constraints such as load flow equations, capacity and voltage constraints and to reduce the real power loss, while subject to a radial network structure in which all loads must be energized. Therefore, the distribution system reconfiguration problem has been viewed as multi-objective problem. In this paper, the hybrid heuristic algorithm has been used for reconfiguration, which is the combination of fuzzy and greedy algorithms. The purpose of the introduction of greedy is to refrain the searching for the period of phase balancing. The incorporation of fuzzy helps to take up more objectives amid phase balancing in the searching. The effectiveness of the proposed method is demonstrated through modified IEEE 33 bus and modified IEEE 125 bus radial distribution system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.2
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• pp.102-110
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• 2012

The objective of this study is to improve the performance of a hybrid ground source heat pump (HGSHP) by optimizing the flow distribution ratio of secondary fluid flow rate between a ground loop and a supplemental loop. Initially, a conventional ground source heat pump (GSHP) was tested to determine an optimum flow rate of the secondary fluid. Based on the selected optimum value, the HGSHP was also tested by varying the flow distribution ratio of the secondary fluid flow rate between the ground loop and the supplemental loop, such as 9:1, 7:3, 5:5, and 3:7. The results showed that the optimum flow distribution ratio of the secondary fluid flow rate was 7:3. The COP of the HGSHP was improved by 19% over the GSHP at a flow distribution ratio of 7:3 and an entering water temperature of $40^{\circ}C$.

• Journal of Distribution Science
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• v.22 no.3
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• pp.83-92
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• 2024

Purpose: With the rapid information distribution of sport-related SNS, sport industry has utilized SNS as technical solution to distribute sport and health-related information. The current study examined the effect of SNS information use for running-specific content on running engagement and psychological well-being. Research design, data and methodology: Data were collected via online survey of participants in marathon events of United States. Descriptive statistics and Chi-square test were conducted to compare demographics and psycho-behavioral outcomes among SNS information users and non-users for running-specific contents. Multivariate hierarchical regression was next employed to examine research hypotheses. Results: A mass-participant running event was used to test seven hypotheses related to the potential role of SNS for running content in promoting running engagement and life satisfaction. In general, findings revealed that use of SNS for running content along with frequency of use can perhaps facilitate running intensity and influence participation in running-related outdoor activities. Furthermore, while overall life satisfaction did not appear to be influenced by use of SNS for running content, there was a demonstrated influence on the individual satisfaction domains. Conclusions: The findings of current study suggest that sport SNS is information distribution media enhancing users' engagement and their six life satisfaction domains. Further implications were discussed.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.7
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• pp.37-44
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• 2013

Phase to ground faults are possibly one of the maximum number of faults in power distribution system. During a ground fault the maximum fault current and neutral to ground voltage will appear at the pole nearest to the fault. Distribution lines are consisted of three phase conductors, an overhead ground wire and a multigrounded neutral line. In this paper phase to neutral faults were staged at the specified concrete pole along the distribution line and measured the ground fault current distribution in the ground fault current, three poles nearest to the fault point, overhead ground wire and neutral line. A simplified equivalent circuit model for the distribution system under case study calculated by using MATLAB gives results very close to the ground fault current distribution yielded by field tests.

• Journal of Distribution Science
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• v.18 no.11
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• pp.5-13
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• 2020

Purpose: This research investigates the cost behavior of the distribution industry. Specifically, we investigate if the ratio of the increase in costs with an increase in sales is consistent with the ratio of the decrease in costs when sales decrease. Traditionally, cost is assumed to be symmetrical. In the case of the distribution industry, it was expected that the downward rigidity of the cost would be shown because it would be very difficult to decide to adjust resources when sales temporarily decrease. Therefore, studies have looked at Korean capital markets based on manufacturing and steel industries. However, no research has been done on the distribution industry. Research design, data, and methodology: To verify the hypothesis of this study, the asymmetry of cost was measured by Anderson et al. (2003). The sample used 28,695 firm-year data from 2002 to 2019 for the KOSPI and KOSDAQ stock markets. Results: The empirical analysis results are as follows. First, asymmetry of cost was observed in the case of the distribution industry. We confirm cost rigidity when sales decreased. Conclusions. This is the first study to look at cost behavior in the distribution industry, and the downward rigidity of cost in the distribution industry is observed.

• Journal of Periodontal and Implant Science
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• v.46 no.3
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• pp.207-217
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• 2016

Purpose: The aim of this study is to analyze and visualize the distribution of patients visiting the periodontology department at a dental college hospital, using a geographic information system (GIS) to utilize these data in patient care and treatment planning, which may help to assess the risk and prevent periodontal diseases. Methods: Basic patient information data were obtained from Dankook University Dental Hospital, including the unit number, gender, date of birth, and address, down to the dong (neighborhood) administrative district unit, of 306,656 patients who visited the hospital between 2007 and 2014. The data of only 26,457 patients who visited the periodontology department were included in this analysis. The patient distribution was visualized using GIS. Statistical analyses including multiple regression, logistic regression, and geographically weighted regression were performed using SAS 9.3 and ArcGIS 10.1. Five factors, namely proximity, accessibility, age, gender, and socioeconomic status, were investigated as the explanatory variables of the patient distribution. Results: The visualized patient data showed a nationwide scale of the patient distribution. The mean distance from each patient's regional center to the hospital was $30.94{\pm}29.62km$ and was inversely proportional to the number of patients from the respective regions. The distance from a regional center to the adjacent toll gate had various effects depending on the local distance from the hospital. The average age of the patients was $52.41{\pm}12.97years$. Further, a majority of regions showed a male dominance. Personal income had inconsistent results between analyses. Conclusions: The distribution of patients is significantly affected by the proximity, accessibility, age, gender and socioeconomic status of patients, and the patients visiting the periodontology department travelled farther distances than those visiting the other departments. The underlying reason for this needs to be analyzed further.

• Journal of the Korean Statistical Society
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• v.22 no.2
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• pp.339-345
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• 1993

It is well known that distribution of functions of eigen values and vectors of a certain matrix plays an important role in multivariate analysis. This paper deals with the transformation of a correlation-type random matrix to its eigen values and vectors. Properties of the transformation are also considered. The results obtained are applied to express the joint distribution of eigen values and vectors of the correlation matrix when sample is taken from a m-variate spherical distribution.

• Communications of the Korean Mathematical Society
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• v.27 no.4
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• pp.835-842
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• 2012

Many researchers have studied the characterizations of probability distributions based on record values. It appears from literature that not much attention has been paid to the characterizations of the Pareto distribution. In this note, some new results on the characterizations of the Pareto distribution by upper record values have been established.

• Journal of the Chungcheong Mathematical Society
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• v.20 no.4
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• pp.411-418
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• 2007

Let $X_1$, ${\cdots}$, $X_n$ be nondegenerate and positive independent identically distributed(i.i.d.) random variables with common absolutely continuous distribution function F(x) and $E(X^2)$ < ${\infty}$. The random variables $X_1+{\cdots}+X_n$ and $\frac{X_1+{\cdots}+X_m}{X_1+{\cdots}+X_n}$are independent for 1 $1{\leq}$ m < n if and only if $X_1$, ${\cdots}$, $X_n$ have gamma distribution.