• Journal of Navigation and Port Research
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• v.33 no.1
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• pp.79-90
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• 2009

The main function of a container terminal is to load container freights into vessels and discharge them from vessels. The container terminal needs to utilize its resources effectively in order to improve the productivity of it. This study deals with the deployment model for yard cranes whose type is RMGC (rail mounted gantry crane). We develop a mathematical model for the deployment of yard cranes. The model considers not only the deployment but also the storage plans. It could be divided into two cases according to whether inter-block movements of yard cranes are allowed or not, during the same period Numerical examples are solved and analyzed to validate the model. Then, additional experiments are performed to compare the performance of the model with that of a previous model without the re-deployment of yard cranes.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.3
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• pp.98-105
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• 2009

It is important for firms to help customers find the products or information they need in order to increase sales and promote return visits to their websites. Hence, the presentation of product information is very important in e-commerce websites. In this research, we study how disposition styles can influence browsing patterns. The test results show that people are inclined to use feature information paths in the vertical disposition style and product information paths in the horizontal disposition style. With vertical disposition, users are more likely to follow feature information paths which may help them focus on comparisons across products.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.4
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• pp.765-772
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• 2011

In this paper, a simulation-based method is presented to dispose direction finders in three dimensional space for locating targets using the directional data. A direction finder(DF) is a military weapon that is used to find locations of targets that emit radio frequencies by operating two or more DFs simultaneously. If one or more DFs are operated in the air, the accuracy of location estimation can be enhanced by disposing them in a better configuration. By extending the line method, which is a well-known algorithm for 2-D location estimation, into 3-D space, the problem of 3-D location estimation is defined as an nonlinear programming form and solved analytically. Then the optimal disposition of DFs is considered with the presented method in which methods of simulation and search technique are combined. With the suggested algorithm for 3-D disposition of DFs, regions in which targets exist can be effectively covered so that the operation effect of DF be increased.

• (The) Research of the performance art and culture
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• no.33
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• pp.97-128
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• 2016

According to the findings of the study, the music composition of the mask play is deeply related to the main characteristics of the scene. The first scene of the play starts with the Byeoksa dance. This particular dance part represents the evil spirit expel ritual. The instrumental accompaniment like and are played for the dance. The last part of the play starts with the Halmi and Yeonggam scene. This scene is played in both the instrumental and vocal music. For the instrumental part , for the vocal part and songs are played. and songs are played on the part of the Halmi's funeral ceremony scene. The instrumental and are played in various scenes for the accompaniment of the dance part. The musical structure of the mask play is flexible. This kind of flexibility of scene structure mainly concerned with the way of musical composition. The main structure of the mask play can be classified into two main styles according to the allocation of the vocal music. In first style, the vocal music is evenly dispersed. In second style, the vocal parts are concentrated in the rear section. As I mentioned earlier, no logical association is found in the matter of the scene arrangement. A scene arrangement has a deep connection with the arrangement of the music in each scene. In conclusion, the mixed arrangement of the scene in mask play is mainly concerned with the matter of the music arrangement in order to maintain the tension of the drama.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.3
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• pp.185-193
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• 2016

In this study, the present deployment of the multiple wave energy converters (WECs) in a floating wind-wave hybrid power generation platform was estimated considering the interaction effect among WEC buoys. The interaction processes of multiple buoys were very complex, since scattered and radiated waves from each buoy affected the others in the array. The interaction analysis of the diffraction and radiation problem by the array of WECs was applied by matched eigenfunction expansion method (MEEM). The analytical solutions were compared with the results of numerical calculation based on WAMIT. The overall performance of 24 WECs installed in the hybrid power generation platform was evaluated by the q-factor representing the interaction effect among buoys.

• Journal of Nutrition and Health
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• v.50 no.6
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• pp.645-654
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• 2017

Purpose: The purpose of this study was to investigate the current status of dietary education carried out by dieticians or nutrition teachers at elementary, middle, and high schools in Gyeonggi province. We compared dietary education status not only among school level but also between dieticians and nutrition teachers. Methods: The survey using self-administered questionnaires was conducted by dieticians or nutrition teachers at 91 schools (43 elementary schools, 33 middle schools, and 15 high schools) in Gyeonggi province in December, 2015. The questionnaire consisted of questions regarding general characteristics of respondents, current status of dietary education, opinion about dietary education methods, and cooperation level of persons concerned. Results: The placement rate of nutrition teachers was 50.5% overall. Only 36 out of 91 schools conducted regular dietary education, and the percentage of schools conducting regular dietary education was significantly different according to school level with the lowest percentage in high schools, equivalent to 20% (p = 0.003). The average annual dietary education time was 12.4 hours, and it was very low in high schools (5.1 hours) and in schools without a nutrition teacher (1.6 hours). The levels of cooperation and support from principals, teachers, parents, and students were significantly lower in high schools than elementary and middle schools (all p < 0.001) and in schools without a nutrition teacher than schools with a nutrition teacher (all p < 0.05). Conclusion: The results show that the level of dietary education is not enough and needs to be improved, especially at middle and high schools and at schools without a nutrition teacher. Government support polices need to be implemented to encourage dietary educational activities.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.51-57
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• 2019

A plant layout problem has a large impact on the overall construction cost of a plant. When determining a plant layout, various constraints associating with safety, environment, sufficient maintenance area, passages for workers, etc have to be considered together. In general plant layout problems, the main goal is to minimize the length of piping connecting equipments as satisfying various constraints. Since the process may suffer from the heat and friction loss, the piping length between equipments should be shorter. This problem can be represented by the mathematical formulation and the optimal solutions can be investigated by an optimization solver. General researches have overlooked many constraints such as maintenance spaces and safety distances between equipments. And, previous researches have tested benchmark processes. What the lack of general researches is that there is no realistic comparison. In this study, the plant layout of a real industrial C3MR (Propane precooling Mixed Refrigerant) process is studied. A MILP (Mixed Integer Linear Programming) including various constraints is developed. To avoid the violation of constraints, penalty functions are introduced. However, conventional optimization solvers handling the derivatives of an objective functions can not solve this problem due to the complexities of equations. Therefore, the PSO (Particle Swarm Optimization), which investigate an optimal solutions without differential equations, is selected to solve this problem. The results show that a proposed method contributes to saving the capital expenditures.

• Proceedings of the Korean Society of Grassland Science Conference
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• 1999.06a
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• pp.91.2-92
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• 1999

본 시험은 1997년 9월부터 1998년 10월까지 제주 화산회토양의 혼파초지에서 양돈 분뇨시용에 따른 목초생산 및 유해성분 축적에 미치는 효과를 규명키 위해 질소시비 수준과 양돈분뇨의 시비수준을 달리하여 분활구 배치법으로 시험이 수행되었다. 목초초장이나 건물수량은 질소시비수준 1, 150 및 300kg/ha에 따라서 통계적으로 유의적 차이를 얻었으나 양돈분뇨시용 1, 750, 1,500 및 3,000kg/ha 효과는 얻지 못했다.(중략)

• Journal of Bio-Environment Control
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• v.32 no.4
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• pp.285-294
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• 2023

The importance of urban green space creation is increasingly recognized as the most realistic and efficient approach for fine dust mitigation in urban areas. Particularly considering the characteristics of domestic cities, the application of buffer green spaces along roads can maximize the efficiency of fine dust reduction without the need for separate green space creation. Accordingly, this study analyzed the fine dust mitigation effects based on the types of plantings in the central dividers and roadside trees in Jeonju City, Jeollabuk-do. To do this, we controlled various external variables of urban space and considered the planting arrangement types in the central dividers, carrying out the analysis using a CFD simulation. The simulation results confirmed that the central dividers with plantings demonstrated more effective ultrafine dust reduction than those without. Moreover, the arrangement of roadside trees showed a greater ultrafine dust reduction effect when adopting a multilayered structure compared to a single layer. Based on these findings, we concluded that installing both trees and shrubs simultaneously in the central dividers and along roads was effective for ultrafine dust mitigation. On this basis, we quantified the dust reduction effects of plants in urban street environments and proposed planting guidelines for roadside green spaces to improve air quality.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.203-210
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• 2003

격자망식 전선배치에 의한 전기비저항 측정기법을 이용한 침출수 누출감지시스템을 개발하여 그 적용성을 평가하기 위하여 현장모형시험을 수행하였다. 현장모형시험을 수행한 결과 침출수 누출지점에서 전기비저항이 크게 감소하여 누출지점을 정확하게 감지할 수 있었다. 격자망식 전선배치에 의한 전기회로적인 효과로 인하여 전기비저항이 감소된 지점과 동일 전선상에 연결된 다른 센서에서의 측정값도 다소 감소하는 경향을 나타내었다. 이를 보정하기 위하여 P-SPICE를 이용하여 전기회로 시뮬레이션을 수행하여 전기회로 효과를 정량적으로 평가하였다 P-SPICE 시뮬레이션의 결과를 토대로 보정계수를 도출하여 현장모형시험결과를 보정하였으며, 보정된 겉과에 의하면 전기회로적 특성에 의한 영향을 효과적으로 제거되어 누출지점에서의 전기비저항 감소가 명확하게 나타났다.