• Journal of Navigation and Port Research
• /
• v.33 no.10
• /
• pp.665-669
• /
• 2009

When maneuvering a ship in a narrow channel or under bridge, the ship operator may take actions of slowdown engine and altering course in order to avoid possible navigational dangers, which may reduce difficulties on navigation or collsion avoidance against other ship and/or bridge. In this paper, taking notice of the stress caused by these actions of slowdown engine and altering course, survey is carried out for whether it is possible to quantify the stress by time delay as an index. Based on the ship handling simulator experiment, it is verified that difficulty of navigation changes is highly correlated with the time delay, which result from compensation actions of slowdown engine and altering course.

• Journal of the Society of Naval Architects of Korea
• /
• v.58 no.6
• /
• pp.431-439
• /
• 2021

The Carbon Fiber Reinforced Plastic (CFRP) material is recently widely used in the composite industry with excellent rigidity and lightweight properties. A ship shaft system requires high standards of safety on torsional strength capacity. The purpose of this study is to verify the applicability of a CFRP shaft system to take the place of metal shaft systems for ships from a viewpoint of torsional strength. Selection of materials and manufacturing method are executed then two geometrically scaled CFRP shaft system models were designed and manufactured with three-layer patterns. The models were used for a series of torsion tests under single and repeated torsional loading conditions. Detailed design and manufacturing methods for a CFRP ship shaft system are documented and the torsion test results are listed in this paper. The results of this study could be useful guidelines on the development of CFRP ship shaft systems and a test method.

• Archives of design research
• /
• v.17 no.4
• /
• pp.15-26
• /
• 2004

After 19th century of Chosun Dynasty Gilsnagmunja-do such as longevity, good fortune, health, well-being which was explosively prevalent and Hyojemunja-do which was panoramically decorated with eight characters of filial piety, fraternal devotion, loyalty, trust, courtesy, commitment, integrity and humility for enlightment of the public under the name of political ideology are consistency or same origin in traditional concept of Orient. Therefore, in view of Western standard, they are showing an illustration and a photograph of characters in design. There are some differences in way of expressions. They were considerably popular not only in Chosun Dynasty but in China, Japan and Vietnam where belong to the cultural territory of chinese characters. Though, Hyojemunja-do which was built-up in the late period of Chosun Dynasty and developed fro chinese mode is a very peculiar iconography and mode of Chosun Dynasty. Hyojemunja-do is also classified from Chinese Nianhua designed for supply of Conficianism ethics or Folk Painting designed for practical use in chinese cultural territory. In the late period of 19th century, Hyojemunja-do which was re-built with creative modeling has been developed in peculiar mode in the province of Kyunggi, Kangwon(Kwan dong region), Kwanseo region, Jeju island and Namdo region by the diversified level of painters.

• Korean Journal of Heritage: History & Science
• /
• v.45 no.3
• /
• pp.238-261
• /
• 2012

This research was carried out about the Bansu which surrounded the Sunggyungwan(成均館), national university in the Joseon Dynasty to get the main characteristics of the landscape at Korean traditional school campus by analyzing cultural meaning and historical origin. The earliest record about the Bansu was in "The Book of Odes(詩經)" as Bansu was the water flowing near the Ban palace(泮宮). But, in the following time, Bansu has become the symbol of the school which was built by the feudal lords and one of very important elements in the temple-school(廟學) landscape. The Bansu of Sunggyungwan at Joseon Dynasty was the streams flowing at the east and west of the school campus and get together at the south. Sunggyungwan was located in the sacred place which followed the special organization of Bansu at the beginning of the Joseon Dynasty. And, Bansu in Joseon Dynasty was influenced by the Bansu in Song Dynasty(宋), but it was different from the Bansu in Ming and Qing Dynasty which has been formulated as the halfround pond in front of the school. This research tried to find the reason why in the Josenon Dynasty the stream flowing around the school was regarded as the Bansu. Bansu was also regarded as an important element in the public school, Hyanggyo(鄕校) and the private Seowon(書院). According to this research, the streams which flows around the Seowon or the Hyanggyo were found as called Bansu. Water stream around the Hyanggyo and the Seowon in the Joseon Dynasty has to be reconsidered under the deep research on the organization of Ban-su.

• Journal of the Society of Naval Architects of Korea
• /
• v.42 no.1 s.139
• /
• pp.1-9
• /
• 2005

Waterjet propulsion is widely used to thrust high speed marine vessels in excess of 30-35 knots by virtue of the high propulsive efficiency, good maneuverability, and less cavitation. From the aspect of power loss, approximately $7-9\%$ of the total power is lost in intake duct due to the flow separation, nonuniformity, etc. Thus, detail understanding of flow phenomena occurring within intake duct is essential to reduce the power loss, as well as noise and vibration. The present work solved 30 incompressible RANS equations to provide complicated viscous flow features of intake duct. The numerical results were compared with experiments and good agreements were obtained for three jet velocity ratios.

• Journal of the Society of Naval Architects of Korea
• /
• v.34 no.2
• /
• pp.11-19
• /
• 1997

The new definition of calibration coefficients is proposed for a five-hole Pitot tube. Two-angle chart calibration other than one-angle variation is considered to improve the accuracy in the measurement of the three-dimensional velocity fields. Several sets of correlation coefficients are introduced for different shapes of the probe tip. The calibration method with one-angle variation is compared with the new two-angle chart calibration method and the improvement of the present method is clearly shown.

• Journal of the Society of Naval Architects of Korea
• /
• v.53 no.4
• /
• pp.282-289
• /
• 2016

Traditional construction method of the stern tube is difficult to control the process and needs excessive working hours. Recently in order to resolve these issues, stern tube unit has been installed for some commercial vessels. The stern tube unit is a monolithic structure of bush and related components. The purpose of this study is to carry out a feasibility study for application of the stern tube unit for a 174K twin skeg LNG carrier. In this study, a 19,000 TEU container carrier installing the stern tube unit has been selected to compare with the deformations of stern for a 174K twin skeg LNG carrier.

• Special Issue of the Society of Naval Architects of Korea
• /
• 2005.06a
• /
• pp.69-75
• /
• 2005

Recently it was reported that the vibration problems on the oil pipe support structure of the crude oil carrier were occurred. in order to investigate the vibration characteristics and the causes of the vibration occasionally. the vibration measurements and impact tests for the oil Pipe structure were carried out. From the measurement results severe vibration was caused by the resonance between the transversal natural frequency of the structure and $6^{th}$ order excitation force of the main engine. Providing the proper countermeasures a series of the vibration analyses were carried out based on the measurement results. From the analysis results, it was concluded that the vibration characteristics of the oil pipe structure were affected by the oil pipes, support structure itself, upper deck structure and the installation spaces and the standard design was established for the crude oil carriers.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.33 no.1
• /
• pp.65-75
• /
• 2015

The findings of basic study on the awareness of falls in terms of Gwanpokdo(Paintings of Viewing Falls) were drawn as follows. First, there is a difference in an esthetic sense that water brings depending on the ratio of falls, and Gwanpokdo(Fall Landscape) in which falls take up more than 20% of the canvas focuses more on falls so that it brings about the awareness of landscape through direct communication with nature. Second, the diagonal composition of the canvas has symmetry between falls and a person viewing the falls, which makes view point even clear. In addition, margins of the canvas were missing due to the effect of True-View Landscape Painting during the late Joseon Dynasty, and overall composition of using the entire canvas became popular. This overall composition is stable and disposed with lopsided composition, so this heightens sense of balance and the meaning of falls. Third, Gwanpokdo(Paintings of Viewing Falls) of Josoen Dynasty showed various types of viewing falls in distant view, but as the distance between falls and persons got closer in the latter part of Joseon Dynasty, falls were no longer utopia but it expressed a sense of beauty and aesthetic contemplation through direct communication with real nature. Fourth, Gwanpokdo(Paintings of Viewing Falls) of Joseon Dynast had many drawings of a person viewing falls and viewing behaviors such as Supyeong gyeong(level landscape), Amgang gyeong(lower landscape), Bugam Gyeong(higher landscape), and glimpse viewing. Fifth, rocks out of landscape elements make falls vivid and are so expressed as yin and yang that falls and rocks are well contrasted with each other, maximizing beautiful scenery of falls. Sixth, woody plant of Gwanpokdo(Paintings of Viewing Falls) was mostly pine trees which symbolized the literati's fidelity and integrity at that time and emphasized the firm meaning of transcending the nature, matching with symbolization of falls.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.37 no.4
• /
• pp.98-104
• /
• 2019

Paju Mok was the local administrative office of the Joseon Dynasty as the administrative and transportation center of western part of Gyeonggi-do and used as a Haenggung when the king visited the royal tomb of the Joseon Dynasty. Paju Mok Government Office was adjacent to Uiju-ro, which connects Hanyang and Uiju in the Joseon Dynasty. Paju Mok Government Office is an important place in the northern part of Gyeonggi, where the king stayed when he visited the Jereung, Hulleung which are located in the northern part of Hwanghae Province and Paju Yeongreung and Jangneung, Paju Mok Government Office was maintained until the 1900s. After the Japanese colonial Period, Government Office buildings are used for other purposes, and their function as a Government office is impaired. In addition, most of the buildings disappeared due to the Korean War, and now the state of Paju Mok Government Office was lost. In order to restore the lost Paju Mok Government Office, it is necessary to study the composition of Government Office, such as the place where Paju Mok Government Office is located and major buildings. Therefore, if you find out the location Estimation, spatial composition and size of Paju Mok Government Office by analyzing and analyzing ancient documents and ancient books related to Paju Mok Government Office, and the topographic map and cadastral map and land survey department during the Japanese colonial period, you can be used as basic data when restoring Paju Mok Government Office.