• Journal of the Society of Naval Architects of Korea
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• v.38 no.4
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• pp.48-55
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• 2001

In this paper, sensitivity analysis for the coupled axial and torsional undamped free vibration of ship propulsion shafting is proposed. The purpose of this study is to effectively and optimally design the resonance frequencies of propulsion shafting affecting barred speed range of main engine by modifying the diameters of intermediate and propeller shafts. The presented method is validated by the sensitivity analysis for the natural frequencies of propulsion shafting of two real large merchant ships. In addition, the changes of natural frequency and resonance main engine speed are discussed in case that the diameter is varied within the range regulated by the rule of shipping register.

• Korean Journal of Remote Sensing
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• v.35 no.5_2
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• pp.831-840
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• 2019

Recently, the span length of long-span bridges is getting longer. As a result, it has been suggested that a new concept called 'super long-span bridge'. In case of super long span bridges, the structure is being complicated and the importance of structural stability is being emphasized. However, until recently, the most commonly used sensors (dual axis clinometer, anemometer, strain gauge, etc.) have got limit about the bridge monitoring. Consequently, we researched the application of a Global Navigation Satellite System (GNSS) to improve the limit of the existing sensors. In this study, the dual axis clinometer, the anemometer and the strain gauge together with the GNSS were used to analyze the behavior of a super-long suspension bridge. Also, we propose the detailed method of bridge monitoring using the GNSS. This study consisted of three steps. First step calculated the absolute coordinates of the towers and the longitudinal axis direction of the study bridge using the GNSS. In second step, through the analysis of the long-term behavior in shortly after construction, we calculated the permanent displacement and evaluated the stability of main towers. Third step analyzed the behavior of bridge by the wind direction and was numerically indicated. Consequently, the bridge measurement using the GNSS appeared that the acquired data is able to easy processing according to the analysis purpose. If we will use together the existing measurement sensors with the GNSS on the maintenance of the super long-span bridge, we figure each error of measurement data and improve the monitoring system through calibration. As a result, we acquire the accurate displacement of bridge and figure the behavior of bridge. Consequently, we identified that it is able to construct the effective monitoring system.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.4
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• pp.39-48
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• 2020

This study examined the type, the structural shapes, and the representation of Sandae, which was the stage for traditional performing arts and constructed for the purpose of imperial processions, ritual ceremonies, banquets, etc. from the Goryeo Dynasty to the Late Joseon Dynasty, and the implications of Seokgasan, which was built in the same era. First, through the history and meaning of Sandae, it was confirmed that Sandae has a homogeneity with Seokgasan, which attempted to imitate the shape of "Mountain" in the outer space. The construction of Sandae was deeply related to the tradition of famous mountains. This is consistent with the fact that 'Famous mountains and lakes" in China was symbolically replicated on the Seokgasan in the front yard of the "Cheongyeongak" in the Goryeo Dynasty. Second, Sandae and Seokgasan differed in their structural shapes, materials, and production methods, but they were used as a stage background for national events by constructing in the shape of the mountain, and appeared in various types. It can be seen that the interest in gardens and art of those days has resulted in various formative expressions of nature through the shape and symbolic meaning of the Sandae that mimics the mountain. Third, it is presumed that the square pond with lotus flowers, which is believed to have been located in the center of the garden of Shin Jaehyo's old house, and the Sugak and Seokgasan adjacent to it were not only elements of the garden, but also functioned as a background for the training and performance stage of Shin Jaehyo's students.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.5
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• pp.113-121
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• 2010

Shumi-sen(須彌山), built by Nohjagong(路子工) in the southern garden of the Palace Garden during the Asuka Period, is understood as being Sumeru based on an Indian perspective of the theory of the origin of universe. It is also viewed as Mt. Myogoh from a Chinese Buddhist worldview. It is thought to be a type of assembled stone structure with Poong-ryoon (風輪)-Su-ryoon(水輪)-Geum-ryoon(金輪)-Ji-ryoon(地輪) carved into each of the 4 stone pieces. These building shapes are thought to have been utilized as stone for exterior construction as opposed to those structures built during the Shilla Period of China and Korea. Aside from Nohjagong's record of Shumi-sen, most of the records from Japan's period of the time suggest that Shumi-sen was an important element that played a role in the scenery of the seasonal outdoor gardens. It is also thought, from the sentences and expressions surrounding the records, that a combination of the seasonal sceneries was utilized centered on Shumi-sen, and that they were all used during festival events. From a perspective of analysis and interpretation dependent on the limited literature and on observation, it cannot be verified whether the Mt. Sumeru Stone(須彌山石) excavated from the Stone God Ruins is the same Shumi-sen that Nohjagong built along with Okyo(吳橋), but it is thought that the 'Shumi-sen type stone structure' that was later built repeatedly as part of the palace garden facilities is identical to the Shumi-sen built at the Imperial Palace's southern garden, or at least a re-built structure based on the Shumi-sen that Nohjagong built with stones and ponds used to create the foundation. Thus, Shumi-sen that Nohjagong supposedly built along with Okyo is suspected to be a figurative rock arrangement and, at the same time, a miniaturized scenic rock arrangement(縮景樹石) that maximized the shape of Buddhism's Shumi-sen. On the other hand, the surface pattern on Mt. Sumeru Stone is very similar to the multi -layers of mountainous pattern icons expressed in the patterns of the Great Golden Incense Burner(百濟金銅大香爐) or Mountain-Water Scenery Sculptural Brick(山水山景紋?) that were built during the Baekjae pcriod aod the rear side of Hwalsuk-jebul Basal Byungipsang(滑石諸佛菩薩竝立像); it is suspected that similar patterns would have been used if patterns were made on Shumi-sen that Nohjagong built. Also in consideration of the physical theory of MI. Sumeru Stone, the Siphon theory of using a pressure difference in water level was applied to the fountain facilities of Mt. Sumeru Stone that seemed to have been built from the practical rock arrangement perspective for the purpose of feasts, etc.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.4
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• pp.1-13
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• 2010

This research was conducted to understand the characteristics and traits of Baekje's palace backyard by studying and analyzing the usage, shape, size, material, and place of origin of the odd-shaped stones found at the remains of Baekje's palace in Waggung-ri, Iksan. The results of the research are as following. The odd-shaped stones found at the Baekje palace backyard were used for two purposes. Some of the stones were used as heaping stones(疊石) for the stone waterfall in the backyard while others were used as ornamental stones(置石) to exhibit the uniqueness and beauty of the stone themselves. The stones used for the waterfall had various shapes and materials and were arranged to symbolize the beauty of natural scenery. On the other hand, the ornamental stones were used to exhibit their beauty of forms. Among the twenty six ornamental stones, four were large, four were mid-sized, and eighteen were small. The twenty four heaping stones used for the waterfall were all categorized as small. All of the stones were not too big, easily coming into sight of human beings. The heaping stones were mostly limestones, and some of them were metamorphic rocks such as marble, quartz, green rock, slaty rock, and phyllite. Almost all of the odd-shaped stones used for Baekje's palace backyard have beautiful patterns and specific forms that resemble natural scenes or animals such as a turtle, terrapin, pig, bear, or elephant. Some of the ornamental stones apparently went through carving to emphasize the unique shapes. Considering the usage and characteristic of the odd-shaped stones, one of the most characteristic feature of the Wanggung-ri palace backyard can be said to be 'the garden of odd-shaped stones'. Meanwhile, according to references, interviews, questionings, and on-the-spot surveys on the people who quarried the stones, the stones found at the remains of the Wanggung-ri palace came mostly from Mt. Cheonho in Hosan-ri, Yeosan-myeon, Iksna, and Mt. Shidae in Dosoon-ri, Wanggung-myeon.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.1
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• pp.46-56
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• 2012

The research results of tracing the Landscape Philosophy of Hageowon garden(何去園) in Musu-dong, Daejon of Youhwadang, Kwon, Iijin(權以鎭, 1668-1734) is as below. The ideological background of the protagonist reflected in Hageowon is the Hyoje Ideology(filial piety and brotherly love, 孝弟) of Sinjongchuwon(painstakingly caring for one's ancestors), Musil ideology(pursuing ethical diligence and truthful mind, 務實) based on sadistic tradition and ethical rationalism, Confucionist Eunil Ideology(ideology on seclusion, 隱逸) of Cheonghanjiyeon(quiet relaxation, 淸閒之燕), and the Pungryu ideology(appreciation for the arts, 風流) of Taoism in the Taoist style. Thus, by substituting these ideological values into a space called Hageowon, the Byulup gardens(別業) such as the Symbolic garden(象徵園), meaning gaeden(意園), and miniascape garden(縮景園) were able to be constructed. 2) The space organization system of Hageowon is generally classified into three phases considering the hierarchy. The first territory is the transitional space having residential features, which is an area to reach peach tree - road(Taoist world 桃經) from Youhwadang(有懷堂). The second territory is a monumental memorial space where the Yocheondae(繞千臺), Jangwoodam(丈藕潭), Hwagae(花階), and the ancestral graves take place, centering on the yards of Sumanheon(收漫軒), and the third territory is the secluded space in the eastern outer garden where the mountain stream flows from the north to south and which is the vein of the left-hand blue dragon(靑龍) of the guardian mountain of Hageowon. 3) Symbolically, the first phase has symbolized the space as a meaningful scenery by overlapping the Confucionist place of Youhwadang - Gosudae(孤秀臺) - Odeokdae(五德臺), and the mystic world of Jukcheondang(竹遷堂) - peach tree - road(桃徑). The second phase, which is the space of Sumanheon(收漫軒), Yocheondae, and Jangwoodam, the symbolical value of Sinjongchuwon(愼終追遠) and the remembrance and longing for one's parents are reflected. The third phase, which is the eastern outer garden of Hageowon and where the mountain stream flows from the north to south, is composed of the east valley(東溪) - Hwalsudam(活水潭) - Sumi Waterfall(修眉瀑布). More specifically, (1) Mongjeong symbolizes the life of gaining knowledge through studying to realize one's foolishness, (2) Hwalsudam symbolizes a transcending attitude in life refusing to pursue wealth and fame, and (3) Jangwoodam symbolizes the gateway to the fairyland to enter the world of mystic gods. 4) The rationale behind Hageowon is that the two algorithms of Confucionism and Taoist Theory appear repeatedly and in an overlapping way. The Napoji(納汚池) and Hwalsudam, which pertains to the prelude of space development, has symbolized Susimyangseong(修心養成, meditating one's mind and improving one's nature), which is based on ethical rationalism. Moreover, if the Monjeong sphere pertaining to the eastern outer garden of Hageowon takes the Confucionist value system as its theme, including moral training, studying, and researching, Jangwudam, Sumi Waterfalls, and Unwa can be understood as a taste of Cheokbyeon(滌煩, eliminating troubles) for the arts where the mystic world is substituted as a meaningful scenery. 5) The miniascape technique called artificial mountain was substituted to Hageowon to construct a mystic world like the 12 peaks of Mt. Mu(巫山). By borrowing the symbolic meaning expressed in old poems, it has been named 'Habang(1/何放), Hwabong(2, 3/和峯), Chulgun(4, 5, 6/出群), Sinwan(7/神浣), Chwhigyu(8, 9, 10/聚糾), Cheomyo(11/處杳), Giyung(12/氣融).' The representative poet reciting artificial mountain were Wangeui(汪醫), Nosamgang(魯三江), Dubo(杜甫), Hanyou(韓愈), Jeonheaseong(錢希聖), and Beomseokho(范石湖). They related themselves with literature by transcending time and space and attempted to sing about the richness of the mental world by putting the mystic world and culture of appreciating the arts they pursued in the vacation home called Hageowon.