As the demand for aesthetic orthodontic treatment increases, the use of self-ligating ceramic brackets is increasing. For stable treatment, there should be no fracture or deformation of the self-ligation ceramic bracket door. Therefore, considering the situation in which labial displacement of teeth occurs in the orthodontic treatment stage. For this study, a model of the mandibular anterior region of a ceramic self-ligating bracket with a passive sliding door mechanism was selected. The measured tensile force data was substituted into the simulation analysis conditions, and the tensile force, stress distribution, and deformation values were analyzed using the finite element method. Using this, it is able to use the design elements of the orthodontic bracket that should be considered as design inputs in the development stage.

Using network betweenness centrality we attempt to analyze the characteristics of Seoul metropolitan subway lines. Betweenness centrality highlights the importance of a node as a transfer point between any pairs of nodes. This ‘transfer’ characteristic is obviously of paramount importance in transit systems. For betweenness centrality, both traditional betweenness centrality measure and weighted betweenness centrality measure which uses monthly passenger flow amount between two stations are used. By comparing traditional and weighted betweenness centrality measures of lines characteristics of passenger flow can be identified. We also investigated factors which affect betweenness centrality. It is the number of passenger who get on or get off that significantly affects betweenness centrality measures. Through correlation analysis of the number of passenger and betweenness centrality, it is found out that Seoul metropolitan subway system is well designed in terms of regional distribution of population. Four measures are proposed which represent the passenger flow characteristics. It is shown they do not follow Power-law distribution, which means passenger flow is relatively evenly distributed among stations. It has been shown that the passenger flow characteristics of subway networks in other foreign cities such as Beijing, Boston and San Franciso do follow power-law distribution, that is, pretty much biased passenger flow traffic characteristics. In this study we have also tried to answer why passenger traffic flow of Seoul metropolitan subway network is more homogeneous compared to that of Beijing.

Tean Mado Shipwreck No. 3 is presumed to have been shipwrecked between 1260 and 1268. It departed from a Southern costal area of Yeosu in Jeonnam Province to Ganghwa Island, its final destination at which the temporal regime of Koryo Dynasty was located. In the shipwreck, a total of 35 wooden tablets were found, and forwarding places, senders, receivers, descriptions, and quantities of freight were written on the wooden tablets. The names of receivers included Kim Jun, who was influential in the late Musin Era of the Koryo Dynasty, and key institutions such as Junmin and Sambyulcho of the Musin force. Twenty wooden tables had lists of food items such as barley, abalone, salted-fermented abalone, mussel, dried mussel, salted fermented mussel, dried shark meat, fish oil, pheasant, and dried dog meat. The food items in the late 13th century were systematically examined using scientifically determined food organic remains and records of wooden tablets among the marine relics of Mado Shipwreck No. 3.

This study examined the food culture of the Koryo Dynasty during the early 13th century based on the records of wooden tablets and marine relics from the 1st and 2nd ships of Mado wrecked at sea off Taean while sailing for Gaegyeong containing various types of grain paid as taxes and tributes. The recipients of the cargo on the 1st ship of Mado were bureaucrats living in Gaegyeong during the period of the military regime of the Koryo Dynasty, and the place of embarkation was the inlet around Haenam (Juksan Prefecture) and Naju (Hoijin Prefecture) in Jolla-do. On wooden tablets were recorded 37 items of rice, cereal, and fermented foods. The measures used in the records were seok [石-20 du (斗)] for cereal, seok [15 du, 20 du] for fermented soybean paste, and pot (缸) and volume (斗) for salted fish. The places of embarkation on the 2nd ship of Mado were Jeongeup (Gobu Prefecture), Gochang (Jangsa Prefecture, Musong Prefecture), etc. On wooden tablets were recorded 29 items of rice, cereal, fermented foods, seasame oil, and honey. The volume measure for yeast guk (麴), the fermentative organism for rice wine, was nang [囊-geun (斤)], and the measure for sesame oil and honey, which were materials of oil-and-honey pastries and confections, was joon (樽-seong, 盛). Honey and sesame oil were luxury foods for the upper-class people of the Koryo Dynasty, and they were carried in high-quality inlaid celadon vases in Meibyung style. Food names and measures written on wooden tablets and actual artifacts found in the 1st and 2nd ships of Mado are valuable materials for research into agriculture, cereal, and fermented foods of the Koryo Dynasty in the early 13th century. Besides, relics such as grains and bones of fish and animals from the Koryo Dynasty are expected to provide crucial information usable in studies on food history of the Korean Peninsula.

The purpose of this paper is to evaluate the noise level and source, reduce the subway lineⅡ noise. As a result of measurement of subway line Ⅱ in Busan the highest value section of uproad line was from Jigegol to Motgol by 89 dB(A). The sections of conversation and listening interference(over 80 dB(A)) were 21 sections(55%) of 38 sections. Among these sections, 15 sections(71%) were produced rolling noise, 3 sections(14%) squeal noise, 2 sections(10%) braking noise and 1 section(5%) fan noise, and then a main noise source was the rolling noise. In case of downroad line, the highest value section was from Busan Metro Art Museum to Centum city, Motgol to Jigelgol by 88 dB(A). The sections of conversation and listening interference(over 80 dB(A)) were 18 sections(47%) of 38 sections. Among these sections, 15 sections(83%) produced rolling noise, 2 sections(11%) squeal noise and 1 section(6%) braking noise were investigated in this study. and then a main noise source was the rolling noise.