• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.71-76
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• 2017

The roll damping problem in the design of ships and offshore structures remains a challenge to many researchers due to the fluid viscosity and nonlinearity of the phenomenon itself. In this paper, the study on viscous roll damping of a circular cylinder was carried out using forced oscillations. The roll moment generated by forced oscillation using a torque sensor was measured for each forced oscillation period and compared with the empirical formula. Although the magnitude of the measured torque from the shear force was relatively small, the results were qualitatively similar to those obtained from the empirical formula, and showed good agreement with the quantitative results in some oscillation periods. In addition, the flow around the circular cylinder wall was observed closely through the PIV measurements. Owing to the fluid viscosity, a boundary layer was formed near the wall of the circular cylinder, and a minute wave was generated by periodical forced oscillations at the free surface through the PIV measurement. In this study, the suitability of the empirical formula for the roll moment caused by viscous roll damping was verified by model tests. The wave making phenomenon due to the fluid viscosity around the wall of a circular cylinder was testified by PIV measurements.

• Bulletin of the Society of Naval Architects of Korea
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• v.21 no.3
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• pp.27-34
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• 1984

When a ship is travelling in following seas, the encounter frequency is reduced to be very low. In that case broaching phenomenon is most likely to occur, and it may be due to wave exciting forces acting on ships. It is thought that the wave exciting forces acting on ships in following seas almost consist of two components. One is hydrostatic force due to Froude-Krylov hypothesis, and the other is hydrodynamic lift force due to orbital motion of water particles below the wave surface. In the present paper, the emphasis is laid upon wave exciting sway force, yaw moment and roll moment acting on ships in following seas. The authers take the case that the component of ship speed in the direction of wave propagation is equal to the wave celerity, i.e., the encounter frequency is zero. Hydrostatic force components are calculated by line integral method on Lewis form plane, and hydrodynamic lift components are calculated by lifting surface theory. Furthermore captive model tests are carried out in regular following waves generated by means of a wave making board. Through the comparison between calculated and measured values, it is confirmed that the wave exciting forces acting on ships in following seas can be predicted in terms of present method to a certain extent.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.566-568
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• 2008

An E-OPMT(Electronically-controllable OPMT) was developed as an alternative of OPMT which could adjust the direction of the generated guided waves in a plate manually. The key idea of controlling the wave direction electronically is based on a few sets of axisymmetric figure-of-eight coils and the magnet which is located for making static omni-directionally biasing magnetic field over the patch. However, in order to explain wave phenomenon generated by this transducer, a new approach is required because there are various combinations between static biasing magnetic field and dynamic actuating magnetic field on the patch, not similar to OPMT. In this paper, the experiments were performed to understand characteristics of E-OPMT and the new theoretical analysis was set up for explaining the result.

• KDI Journal of Economic Policy
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• v.39 no.2
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• pp.53-74
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• 2017

This paper focuses on the recent extraordinary growth of Chinese cross-border online shopping and draws implications for firm strategies and government policies in Korea to utilize the phenomenon as an opportunity to expand into a broader market via e-commerce exports. I conduct a survey of Chinese cross-border online consumers to identify constraining and determining factors during the stages of their purchase decisions of Korean products. Given the fact that Chinese cross-border online shopping is at the incipient stage and consumers have expressed a strong intent to repurchase, future strategies should focus on attracting new consumers. Accordingly, Korean firms should build a powerful brand image, improve product quality and post-purchase services, and take full advantage of the popularity of the Korean Wave. Meanwhile, the government must step up policy efforts by, for instance, improving e-commerce export statistics, simplifying logistics and clearance procedures, and building trust in Chinese consumers.

• International journal of advanced smart convergence
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• v.9 no.3
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• pp.105-117
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• 2020

The "New Korean Wave" (Shin Hallyu) phenomenon, which is represented by the global popularity of BTS and director Bong Joon-ho's film "Parasite," is making the world excited. The influence of the Korean Wave is not only on politics, society, and culture, but it also has considerable economic ripple effects. We applied individual in-depth interviews with seven media and marketing experts in China to assess the changes in the impact of Korean cultural content (i.e., Hallyu content) and examine the possibility of marketing for Korean small and medium-sized enterprises (SMEs) products using Hallyu content. Considering its massive market potential, China is still an attractive target for Korean companies and is of even greater importance to SMEs, which are highly dependent on exports and lacking marketing budgets as well as a professional workforce. Korean businesses and the economy at large would get a real boost if they could penetrate the Chinese market by utilizing the strength of Hallyu content. Based on the results of the in-depth interviews, the conclusion of our study suggests the direction of advertising strategy on how Korean products can attract the minds of Chinese consumers by utilizing the Shin Hallyu. This research is a practical study that diagnoses the reality of the Korean Wave in China objectively and has excellent practical implications as it proposes methods of how SMEs should use Hallyu for their marketing strategies.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.490-495
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• 2003

In steel-making process of iron and steel industry, the purity and quality of steel can be dependent on the amount of CO contained in the molten metal. Recently, the supersonic oxygen jet is being applied to the molten metal in the electric furnace and thus reduces the CO amount through the chemical reactions between the oxygen jet and molten metal, leading to a better quality of steel. In this application, the supersonic oxygen jet is limited in the distance over which the supersonic velocity is maintained. In order to get longer supersonic jet propagation into the molten metal, a supersonic coherent jet is suggested as one of the alternatives which are applicable to the electric furnace system. It has a flame around the conventional supersonic jet and thus the entrainment effect of the surrounding gas into the supersonic jet is reduced, leading to a longer propagation of the supersonic jet. In this regard, gasdynamics mechanism about why the combustion phenomenon surrounding the supersonic jet causes the jet core length to be longer is not yet clarified. The present study investigates the major characteristics of the supersonic coherent jet, compared with the conventional supersonic jet. A computational study is carried out to solve the compressible, axisymmetric Navier-Stokes equations. The computational results of the supersonic coherent jet are compared with the conventional supersonic jets.

• Industry Promotion Research
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• v.9 no.1
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• pp.189-202
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• 2024

It is not the water veins themselves that are distributed on Earth that are harmful, but the water vein waves generated from the water veins are harmful to human health. The natural frequency of the Earth is 7.83 Hz, but in order to sleep deeply, you must go down to a delta wave of 2 to 3.99 Hz, which is lower than this frequency, to achieve the deepest sleep and maintain your health. However, if you sleep in a place with dowsing waves, the dowsing waves interfere with your brain waves, making it difficult to sleep well, and you may have nightmares. Even when you wake up, your body is not refreshed and your fatigue does not go away, so you feel tired and tired easily. If this phenomenon continues, the body's resistance decreases and immunity weakens, which can eventually cause illness and cause various diseases, which can harm one's health. In other words, the safest and most effective way to deal with water veins is to avoid places with water veins and simply change your sleeping position to a place without water veins, and you can live a healthy and happy life through examples.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.2
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• pp.122-138
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• 2001

It is well known that whcn waves propagating on a shallow water suddenly encounter a much deeper water they do not propagate further but are reflected. If we apply this phenomenon to a harbor by making the harbor depth much greater than outside, we could improve the harbor tranquillity by making the waves impinging into the harbor be reflected at the harbor entrance. In the present paper, first we apply the numerical models based' on the mild-slope equation and extended mild-slope equation to calculate the long wave resonances in a rectangular harbor with a very large depth discontinuity at its entrance to find that the difference between the models is almost negligible. By applying the numerical model to a realistic model harbor whose inside is entirely dredged, it is found that the effect of dredging is insignificant when the inside depth is twice the outside one but tripled inside depth significantly reduces the long waves of period of one to five minutes whieh may exert a bad influence on ship motion. Moreover, even when only a portion of the harbor basin is dredged, the cffect of dredging in the dredged area is found to be comparable to that of entire dredging, showing that the dredging of harbor basin can be a countenncasure for harbor resonance.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.261-268
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• 2022

No language can be separated from other languages and exist independently. When a language comes in contact with a foreign culture, they continuously affect each other and bring changes. Hallyu boom(Korean wave), which was derived from the emergence of K-drama and K-pop due to rapid developments in global scientific technologies and digitization after the 90's, affected the Chinese language. As a result, neologisms that are derived from the Korean language are being commonly used for making exchanges and becoming social buzzwords. Neologisms derived from Korean reflect the effects and results of language contact between the two languages. We examined the background and cause of Chinese neologisms derived from Korean based on the sociocultural factors and psychological necessity, and explained neologisms by using four categories of transliteration, liberal translation, borrowing Korean-Chinese characters and others. Despite having the issue of being anti-normative during the process of coining new words, neologism enriches Chinese expressions and is a mirror for social culture that reflects the opinions and understandings of young Chinese people who pursue novelty, change, innovation and creativity in linguistic aspects. We hope that it will serve as an opportunity for the young people in Korea and China to change their perceptions and become more friendly by understanding each other's language, culture and by communicating. We also expect to provide assistance in regard to teaching and learning the applications of Korean-Chinese language fusion at Chinese education fields.