• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.05a
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• pp.122-125
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• 2018

조선은 개국 이후 일본과의 교린정책을 위해 막부의 요청에 따라 총 20차례 통신사를 파견하였다. 그 동안 우리 학계에서는 통신사행과 관련한 제도와 문학, 문화교류, 통신사선의 건조, 상호간의 인식, 외교와 의례, 영접 등을 중심으로 연구가 이루어져 왔고, 통신사행의 이동경로인 항로와 항해에 대해서는 상대적으로 연구가 미진하였다. 본 연구는 임란 후 1607년부터 1763년까지 일본에 파견된 12차례 통신사행의 해상항로와 항해에 대해 현지답사와 사료를 중심으로 분석한 것이다. 이 연구는 통신사선의 항로와 항해에 대한 최초의 학술연구로서 통신사행에 대한 연구의 질과 폭을 넓히는 계기가 될 것이고, 해양사적으로는 한선의 항해술을 이해하는 단초가 될 것이다. 그러나 항해의 실체에 대해서는 통신사선의 사공과 격군이 남긴 사료가 전무하여 구체적으로 밝히는 데는 한계가 있었다. 이는 차후 연구를 통해 보완할 필요가 있다.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.28 no.1
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• pp.7-13
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• 2020

A significant growth in local air traffic volume is leading to airway congestion and flight delays especially for Incheon-China and Incheon-Europe sectors. A key method to increase the airway capacity is to place a supplemental airway parallel to the existing one and in cooperation between the aviation authorities between China and Korea, a dual airway track was implemented on December 6, 2018. Here, we use airline A's flight data to analyze the congestion change effect of the new airway. Results show total delay time to Europe is reduced 51% (13.4 to 6.6 minutes) as the delay distribution for 16-30 minutes, 31 minutes and greater decreased from 23.2% to 8.2% and 8.7% to 1.0% respectively. The delay to China also decreased but the drop is not as significant as flights to Europe. This is caused by the difference in flight distance, traffic volume, and characteristics of flights landing and transiting China. Flights to Europe show a broad distribution in altitude allocation and reduction in aircraft separation demonstrating the effectiveness of a dual airway track.

• Journal of Korean Society of Steel Construction
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• v.16 no.3 s.70
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• pp.315-324
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• 2004

This study performs a yield line analysis of welded T-joints in cold-formed Square Hollow Sections (SHS) with the branch in axial compression. The existing yield line models proposed by Koto, Packer, Zhao, and CIDECT and the proposed yield line model of the previous study are compared, using the existing test results of welded T-joints in cold-formed SHS. The yield line model suggested in the previous paper, which is based on the simplified yield line analysis, is reviewed to evaluate its application limit on cold-formed SHS T-joints. In the proposed model, the round corner of the cold-formed SHS section and weld size are taken into account. Finally, the validity range of yield line analysis is determined by observing the actual failure modes and comparing the test value with the analysis value, set as ${\beta}^{\prime}{\leq}0.8$ where ${\beta}^{\prime}=0.8$, ${\beta}^{\prime}=b_1^{\prime}/b_0^{\prime}$, $b_1{^{\prime}}=b_1+t_0$ and $b_0{^{\prime}}=b_0-t_0$.

• Journal of Korean Society of Steel Construction
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• v.23 no.5
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• pp.547-555
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• 2011

An unstiffened top and seat angle connection is a type of partially restrained connection that is suitable for low- and medium-rise steel buildings. The plastic moment resisting capacity of such connection is needed in practical design, in addition to the accurate prediction of the initial rotational stiffness. Therefore, most of the studies conducted for the mentioned connections were performed to predict the initial stiffness and the plastic moment resisting capacity with varying geometric properties. The main parameters of such experimental tests were the thickness and high-strength bolt gauge distance of AISC LRFD-type A top and seat angle connections. Based on the test results, the analytical model was also proposed in this study. The applicability of the proposed model was verified by comparing the test results from this study with those of other studies.