• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.4
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• pp.403-411
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• 2020

This paper discusses the main findings of the development of the twin-hull Car ferry for island freight and passenger transport. The final model had a 19 m wide beam to create enough space for cars on the deck area and thus, enhance the economic feasibility in the market. The vessel had a V-shape with a bulbous bow to minimize the wave-making resistance and the hydrodynamic performance of the ship was verified through computational fluid dynamics. Multi-objective optimization problems of Pareto simulated annealing were used to achieve a weight reduction of approximately 3.9 % and reduce the manufacturing cost. The main results obtained in this study are expected to be useful to engineers and professionals in related industries interested in research on twin catamaran.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.1
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• pp.41-44
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• 2009

Lipoma is most common tumor that compromises 4% to 5% of all benign neoplasm, but in oral cavity it is uncommon. In oral cavity, lipoma presents painless, asymptomatic, slow growing, but sometimes it grows to larger size causing deformities, mastication and speech difficulties. While lipoma in commonly affects female patients (68-73%), oral lipoma appears more frequently in male patients. The majority of oral lipoma is seen after the age of forty (uncommon in children). Lipoma of oral cavity and maxillofacial region occurs most commonly in the parotid region, followed by the buccal mucosa, lip, tongue, palate, mouth floor, gingiva in order. A treatment of lesion is surgical excision with recurrence not expected. In this paper we present the case of a patient who has Lipoma in the mouth floor.

• Korean journal of communication and information
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• v.34
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• pp.275-305
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• 2006

The main research question of this paper is as follows: How can broadcasting both cause the crisis in democratic participation and yet also offer the solution? The contradiction in broadcast localism has never been adequately resolved in spite of regulation at all in practice, in that localism simply cannot account for the diversity of modern life and for the external forces that incorporate local communities into much larger economic and communications network. The concept of locality in local television, however, has been multiplied and enlarged in order to adjust to "time-space compression". Recently the local television have been "interface" combining and negotiating the globalization of media market and the decentralization of political power, the economies of scale and the activation of local democracy, consequently aiming at the horizontal-cooperative network instead of old vertical-dependent one.

• Korean journal of communication and information
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• v.69
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• pp.170-194
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• 2015

New institutionalism is one of the research perspective, explaining political, economic, social phenomena through institutions. It is seeking more accurate diagnosis and solution of societal problem. What is good media for community? And how it should be operate? These questions are related to design and improvement of media system. Now we need to better approaching method for higher explanatory power about media institutions. From this context, the purpose of this study is exploring application of new institutionalism to media system. The major findings are as follow: At first, the new institutionalistl approaches can be apply the research fields of media policy/law and media organizations. Two, we suggest main research questions and research methods to each of that. This study has implication as more systematic and integrated approach to the research fields of media institution.

• Survey Research
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• v.10 no.3
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• pp.107-130
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• 2009

This study examines the factors affecting Korean firms' adoption of maternity protection practices. From a neo-institutional perspective, we argue that firms adopt institutionally legitimized practices mainly for their legitimacy concern rather than technical efficiency. Analysis of data from Establishment panel survey reveals that firms which belong to public sector, has received foreign investment, bench-mark leading firms, or have HR department are more actively adopting maternity protection practices and are showing lower level of decoupling between model and reality. These results imply that legitimacy concern matters among Korean firms in terms of adopting maternity protection practices. We propose that it is important for government agencies to take institutional factors into account when they try to promote maternity protection policy among firms in dealing with the problems of low fertility and gender equity.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.5C
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• pp.503-511
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• 2006

H.264 adopts new coding tools such as intra-prediction, loop filter, etc. The adoption of these tools enables an H.264-coded bitstream to have more information compared with previous standards. In this paper we proposed an effective spatial error concealment method for H.264. Among the information included in an H.264-coded bitstream, we use intra-mode for recovering a damaged block. This is because prediction direction in intra-mode is highly correlated to the edge direction of a lost macroblock. We first estimate the edge direction using intra-modes of blocks adjacent to a lost macroblock, and classify the area in a damaged macroblock into the edge and the flat area. And then our method recovers pixel values in the edge area using edge-directed interpolation, and recovers pixel values in the flat area using weighted interpolation. Simulation results show the proposed method yields better video quality than conventional approaches by 0.35 to 5.48 dB.

• Journal of Aquaculture
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• v.20 no.3
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• pp.190-193
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• 2007

Viability, early growth and sex ratio of induced gynogenetic diploid bagrid catfish (Leiocassis ussuriensis, Siluriformes) were examined. Survival rates of gynogenetic diploids and normal bi-parental diploids up to 180 days post hatching were not significantly different (P>0.05), and consequently resulted the mean percent survivals of 76% (gynogens) and 78% (bi-parental progeny) at the end of growth trial. Growth in both body weight and total length of gynogenetic diploids was also similar to those of normal diploid controls (P>0.05). Gynogenetic bagrid catfish displayed a similar level of ovarian development when compared to bi-parental diploid females, as judged at 10 weeks post hatching. Sex ratio of bi-parental progeny was normal 1:1 whereas all-femaleness was observed in gynogenetic progeny (P<0.05), suggesting that the genetic sex determination mechanism of this species should be XX-XY based female homogamety.

• The Journal of Korean Association of Computer Education
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• v.14 no.1
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• pp.55-67
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• 2011

Due to recent various online problems, the necessity of information security education has increased. The information security education was strengthened thanks to the informatics curriculum of middle school in 2007, but the educational fields lacked detailed educational materials that could be utilized. Thus to give appropriate information security education for elementary and middle school students, this research developed an unplugged activity for them. The activity was designed by applying Lickona's integrated ethical model and design patterns of unplugged activities, and developed through expert's review and pilot tests targeted to elementary school students. Developed activity was applied to 21 middle school students and the usability was evaluated. As results, first, the activity showed similar expectations from the previous activities. Second, persistence was also similar or higher compared to the previous activities, so the activity developed from this research secured the minimum usability. The unplugged activity developed from this research would give implications in producing various educational contents for information security education.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1993.05a
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• pp.33-41
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• 1993

The objectives of this experiment performed were to determine the potential using of solar radiation to destroy organic contaminants in water by photolysis and to develop the process and improve its performance. We used lab, scale of recirculation photoreactor with 30, 50, 80ppm initial concentration of TCE and Ti $O_2$ anatase, respectively. Adsorption constant, reaction constant were obtained and compared using the Langmuir-Hinshelwood kinetics equation. Ti $O_2$ anatase demonstrated the highest conversion ratio co TCE among Ti $O_2$ anatase, ZnO and F $e_2$ $O_3$ in this experiment. It was shown that in case of two component system, TCE+ phenol, as the concentration of phenol increased in the feed solution, TCE decomposition rate decreased.

• School Mathematics
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• v.13 no.3
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• pp.405-422
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• 2011

In this study, we consider the meaning of one-to-one correspondence through theoretical background under operation of matrix. On algebraic point of view, its significance is 'through one-to-one correspondence from a set with given structure, become a methods in order to induce an algebraic system in to a new set.' That is a key idea making isomorphic structure. Such process experiences necessity of mathematical fact, as well as the deep understanding of one-to-one correspon -dence. Also that becomes a base for develop a various mathematical concepts, such as matrix, exponential laws, symmetric difference, permutation and so on. This study help teachers and students to understand of mathematical concepts meaningfully and to facilitate teacher's professional development.