• 한국전기전자재료학회논문지
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• 제14권4호
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• pp.297-301
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• 2001

In this paper, the temperature distribution and thermal stress analysis of 50kVA pole cast resin transformer for power distribution are investigated by FEM program. The one body molding model (Model 1) and air duct model (Model 2) are designed and their temperature distribution are analysed. The temperature rise value is about 105.5 deg in the model 1 and 65.28 de in the model 2. The temperature change of secondary winding is more than primary winding according to load ratio. The concentration part of Von Mises Stress occurs at interface between glass fiber and epoxy.

• 한국도로학회논문집
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• 제16권1호
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• pp.49-56
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• 2014

PURPOSES : This study was done to model the headway distribution of rural two lane roads. METHODS : Time headway data for the various level of traffic volumes was measured in twelve sites. Based on the time headway data, existing seven mathematical models were evaluated and selected by comparing graphically the measured and theoretical distributions and conducting the Chi-square test. RESULTS : The results show that both the Schul model and Composite Model were the most appropriate models of the models. Based on the measured time-headway distributions, this study proposed a new headway distribution model by the shift of the Schul model. CONCLUSIONS : The shifted Schul model has the ability to describe time headway distirbutons for random, intermediate, and constant-headway states.

• Journal of Hydrospace Technology
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• 제1권1호
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• pp.41-56
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• 1995

Flew control devices, such as flow liners, are frequently introduced in a cavitation tunnel in order to reduce the tunnel blockage effect, when a three-dimensional wake distribution is simulated using a complete ship model or a dummy model. In order to estimate the tunnel wall effect and to evaluate the effect of flow liners on the simulated wake distribution, a surface panel method is adopted for the calculation of the flow around a ship model and flow liners installed in a rectangular test section off cavitation tunnel. Calculation results on the Sydney Express ship model show that the tunnel wall effect on the hull surface pressure distribution is negligible for less than 5% blockage and can be appreciable for more than 20% blockage. The flow liners accelerate the flow near the afterbody of the ship model, so that the pressure gradient there becomes more favorable and accordingly the boundary layer thickness would be reduced. Since the resulting wake distribution is assumed to resemble the full scale wake, flow liners can also be used to simulate an estimated full scale wake without modifying the ship model. Boundary taper calculation should be incorporated in order to correlate the calculated wake distribution with the measured one.

• 태양에너지
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• 제17권3호
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• pp.3-11
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• 1997

Recently the construction of atrium buildings has increased but along with it many problems in thermal environment have arised. since the exterior wall of glass, indoor temperature is greatly influenced by weather conditions and since the space volume is very large, the vertical air temperature is not uniform. So, in this study, a Vertical Temperature Distribution Model was developed to predict the vertical air temperature of an atrium and evaluate the effects of the design parameters on the air temperature distribution of an atrium. To consider the characteristics of the vertical air temperature distribution in an atrium, the Satosh Togari's Macroscopic Model was used basically for the calculation of the vertical air temperature distribution in large space and the solar radiation analysis model and natural ventilation analysis model in atrium. And to calculate the unsteady-state inside wall surface temperature(boundary condition), the finite difference method was used. For the verification of the developed temperature distribution program, numerical evaluation of air flow by the ${\kappa}-{\varepsilon}$ turbulence model and in-situ test was conducted in parallel. The results of this study, the developed temperature distribution program was seen to predict the thermal condition of the atrium very accurately.

• 한국멀티미디어학회논문지
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• 제7권11호
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• pp.1531-1539
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• 2004

본 논문은 입술의 경계선을 효과적으로 추출하는 방법을 제안하였다. 입술 형태는 PDM(Point Distribution Model)과 주성분 분석법을 이용하여 표현하고 입술 경계선은 GLDM(Gray Level Distribution Model)을 기반으로 표현하였다 입술 경계선 추출은 모델에 대한 입력영상의 정확도에 대한 목적함수를 최적화하는 문제로 단순화하였으며, 최적화를 위해 다운힐 심플렉스(Down Hill Simplex) 알고리즘을 이용하였다. 탐색과정에서 지역 최소점으로 수렴하는 문제를 해결하기 위하여 입술 형태 모델의 형태계수를 GMM(Gaussian Mixture Model)을 이용하여 표현하였다. 형태계수에 대한 GMM을 이용하여 입술의 대략적인 형태를 찾고, 이때 사용된 mixture 성분을 이용하여 탐색과정에서 입술의 형태를 조정함으로써 지역 최소점에 수렴하여 입술의 정확한 위치를 찾지 못하는 문제점을 해결하였다. 여러 영상을 대상으로 실험하여 좋은 결과를 얻었다.

• 전기학회논문지
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• 제62권9호
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• pp.1199-1208
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• 2013

In recent years, the development of application programs for distribution system analysis and control has been essential part for distribution management system (DMS). In this paper, we propose the common database for application programs of distribution management system. The proposed database model has several characteristics as followings. First, the proposed database model is designed for the common use of almost the whole distribution application software. The static equipment model and dynamic type tables are mixed and the parallel table structure is applied. Second, the linked list structure of database are used for the fast processing of applications. The database model includes the hierarchy and non-hierarchy distribution system structure. Third, the reduction method of distribution database is applied. For this, we present the network reduction rules. The basic concept of reduction rules are the electrical unification of successive line section which has not lateral branches and the removal of simple lateral branches which has no devices and other laterals. Proposed database model is tested for the Jeju system of Korea Electric Power Corporation (KEPCO). Through the test, we verified that the proposed database structure can be effectively used to accomplish the distribution system operation.

• 한국농공학회지
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• 제40권2호
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• pp.59-68
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• 1998

This study was conducted to derive optimal design floods by generalized gamma distribution model of the annual maximum series at eight watersheds along Geum, Yeongsan and Seomjin river systems. Design floods obtained by different methods for evaluation of parameters and for plotting positions in the generalized gamma distribution model were compared by the relative mean errors and graphical fit along with 95% confidence limits plotted on gamma probability paper. The results were analyzed and summarized as follows. 1. Basic statistics and parameters were calculated by the generalized gamma distribution model using different methods for parameters. 2. Design floods according to the return periods were obtained by different methods for evaluation of parameters and for plotting positions in the generalized gamma distribution model. 3. It was found that design floods derived by sundry averages method for parameters and Cunnane method for plotting position in the generalized gamma distribution are much closer to those of the observed data in comparison with those obtained by the other methods for parameters and for plotting positions from the viewpoint of relative mean errors. 4. Reliability of design floods derived by sundry averages method in the generalized gamma distribution was acknowledged within 95% confidence interval.

• 유통과학연구
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• 제20권4호
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• pp.21-31
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• 2022

Purpose: The study focuses on the distribution of brand love on customers' behavioral intention at five-star hotels in Vietnam. Furthermore, the study also assesses the role of mediating variables and moderating variable involved in the research model. Research design, data and methodology This research surveys 458 customers using the services of five-star hotels in Vietnam through questionnaires on online platforms. Data cleaning and data analysis using SPSS 25.0 software combined with Smart-PLS 3.0 software were used in the research to evaluate the measurement model and structural model. Results: From the results of the structural model evaluation, it shows the positive distribution of brand love on customers' behavioral intentions towards five-star hotels in Vietnam. The mediating roles of brand engagement, brand equity, customer motivation, and the participation of the moderating variable, customer expectations, are determined by this research model. Conclusions: Based on the study results, the distribution of brand love positively affects customers' behavioral intention at five-star hotels in Vietnam, giving recommendations that have a positive impact on customer behavioral intention. In addition, the study shows the role of mediating variables as well as exploring the moderator's (customer expectations) in the distribution of relationships between customer motivation and customer behavioral intention.

• 한국철도학회논문집
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• 제5권2호
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• pp.77-83
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• 2002

In this paper we present a nonlinear programming model for the train seat capacity distribution with a numerical example. The model finds the optimal capacity distribution methods which minimize the sum of the differences between the demands and the seat capacities. Also the model provides the information on the degree of the discrepancy between the demand and the seat capacities. One can use the model as a tool for planning train seat capacity planning.

• 한국지하수토양환경학회지:지하수토양환경
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• 제8권4호
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• pp.21-26
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• 2003

황과 Powers(2003)는 입도분포와 공극크기분포에 로그분포함수를 적용하여, 입도분포로부터 토양수분특성을 직접 추정하는 간단한 모형을 개발하였다. 본 연구의 목적은 황과 Powers(2003)가 개발한 모형의 추정능력이 토성에 의해 영향을 받는가를 밝히는 것이다. 연구결과, 모형은 토성에 의해 영향을 받았고, 특히 토양내 세립질 분율이 커질수록 모형의 추정능력은 감소하였다. 또한 입도와 공극크기사이의 관계를 비선형으로 가정한 비선형모형이 선형모형보다 토성에 관계없이 그 추정능력이 크게 나타났다.