• Journal of the Society of Naval Architects of Korea
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• v.50 no.5
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• pp.324-333
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• 2013

Recently, rudder erosion due to cavitation has been frequently reported on a semi-spade rudder of a high-speed large ship. This problem raises economic and safety issues when operating ships. The semi-spade rudders have a gap between the horn/pintle and the movable wing part. Due to this gap, a discontinuous surface, cavitation phenomenon arises and results in unresolved problems such as rudder erosion. In this study, we made a rudder model for 2-D experiments using the NACA0020 and also manufactured gap flow blocking devices to insert to the gap of the model. In order to study the gap flow characteristics at various rudder deflection angles($5^{\circ}$, $10^{\circ}$, $35^{\circ}$) and the effect of the gap flow blocking devices, we carried out the velocity measurements using PIV(Particle Image Velocimetry) techniques and cavitation observation using high speed camera in Seoul National University cavitation tunnel. To observe the gap cavitation on a semi-spade rudder, we slowly lowered the inside pressure of the cavitation tunnel until cavitation occurred near the gap and then captured it using high-speed camera with the frame rate of 4300 fps(frame per second). During this procedure, cavitation numbers and the generated location were recorded, and these experimental data were compared with CFD results calculated by commercial code, Fluent. When we use gap flow blocking device to block the gap, it showed a different flow character compared with previous observation without the device. With the device blocking the gap, the flow velocity increases on the suction side, while it decreases on the pressure side. Therefore, we can conclude that the gap flow blocking device results in a high lift-force effect. And we can also observe that the cavitation inception is delayed.

• Journal of Technologic Dentistry
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• v.19 no.1
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• pp.91-111
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• 1997

An aim of this study is to find out influenced factors of satisfaction degree on the clinical practice for the dental technology student and it can be provided the basic necessary data for the educational planning of the curriculum for the clinical practice. The target of study are selected form 7 junior health college students and colleges are located in around seoul form 14 junior health college throughout the nation. The questionnaries were distributed between 24th Feb to 30th July in 1997 to the 100 dental technicians who finished clinical practice and entered profession in 1997. All collected data were analysed by using SPSS/PC, Technical Statistic, One-Way ANOVA, Ttest, Person Correnlation Coefficient, Chrobach Alpha Coefficient and the result of the study is follow. 1) The satisfaction degree were classificated as 7 aspect and overall average score was 3.042. During that period satisfaction of personal relation aspect(M=3.737) shows highest level. Satsfiaction of clinical parctice(M=3.571) shows as second, Satisfiaction of environment(M=3.028), Satisfaction of guidance(M=2.915), satisfaction of subject are ordered of their scores. According to above study satisfaction's degree of subject show lowest level. 2) According to the result of verification of study. general character of student and satisfiaction degree has not much relation with sex, location of college, religion, period for enrolling college, teaching method of clinical practice. But the result show similar relation with following items. Satisfaction if subject and satisfaction of clinical practice(P=0.000), place of clinical practice and satisfaction of clinical practice(P=0.002), Academic record of college and satisfaction of clinical practice(P=0.000). 3) The relation of satisfaction(Subject, method of teaching, environment, period, rating, personal relation) of clinical practice and age of investigation's target Older student show higher satisfaction(P=0.040). Also method of teaching, environments, period, rating, personal relation has similarities with satisfaction. Therefore student who has higher satisfaction of clinical practice they also have higher rate for subject, environment, period, personal relation. 4) The result fo investigation, most interesting subject was crown & bridge and most difficult factor was too many simple-works to the student. One of ideal factor was discussing with counselor before they choose place for clinical practice. Third grade and first semester is most efficient time for clinical practice and 8 week is proper period for clinical practice. Clinical practice is absilutory mecessary and we find out most student rated positively. However we need more specific study about satisfcation of each subject. Because it shows lowest level and we need more pay attention for planning of clinical practice.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.4
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• pp.82-94
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• 1999

According to Korean's geographical features of Taek Li Ji, the best location for human settlements is on the vicinity of a stream among a stream, an river and a sea, and not far from a ridge. The researcher chose one of best village which is called Yougokmaeul in Bonghwa-Gun, Kyungsang-Do. This village was created a gathering village with the same surname, can be translated as a hen and the front mountain can be seen as a rooster in the view of the shape of geographical features. As it were, the shape of this village and the cultivated land seems to be an egg inside a nest of a parent's chicken in the respect of the analogy of the theory of P'ungsuchiri which is known as Feng Shui in China and geomancy in the western world, and to effect the defensive psychology of the living environment in the terrain inland. This village is the studying place, Suckchunjungsa as the lecturing and studying place for their following students within the Chunghadonchun, the studying Yougok village, and even the ritual place performing ancestral sacrifices and the first incoming ancestor's graves in the same geographical system. The house site of the first incoming resident is surrounded the countian and is located in the front of Backsulryount which is the main mountain through Moonsu-san in the branch mountain of Korean's mountain system. Backsulryoung which is to be seen as the white peak, is symbolized the head of a hen which is to relate to a mysterious turtle in the view of P'ungsuchiri. And the pavilion which is called Chungamjung is sited on the rock of a shape of turtle which is symbolized to live longer. In the section of the mountain and water, Lee Jung Hwan mentioned a living place near the mountain stream is the best residential area and a landscape which is composed by a stream between mountains make a pleasure spirit and a bright feeling and make a refined person. If one can reach in the graceful mountain make a pleasure split and a bright feeling and make a refined person. If one can reach in the graceful mountain half day away, this kind of place must be a best living residential area to live. But this village was structured all in one place. And one of the ideas tangibly reflected in traditional Korean society's view of life and nature is the seclusion based on the Taoism. This kind of a dreamy thoughts make a dream to keep the paradise in our ancestors' mind. This kind of utopia is Chunghadonchun which is structured 5 aspects from the utopian gate near the Samgaesuewon to the village. These 5aspects is expressed by some Confucian thoughts as a small cosmos individually. On the third aspects which is the center among these aspects, the Suckchunjungsa which was made a seclusion place to devoting himself to his studies with refined tastes. The word of Jiju-am, Gangpung-dae, Jaewol-dae and Biryoung-pock are all expressed to cultivate one's moral character and to seek the truth by the Confucius'theory through the nature.

• The Journal of Korean Society for School & Community Health Education
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• v.6
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• pp.89-107
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• 2005

The purposes of this study were to investigate the recognition and the needs and problems of in-service education for school nurse, and to suggest the desirable guidelines, for supples the basic data of in-service education for school nurse to upgraded the quality as school nurse's professional specialist. The subjects of this study were 376 school nurses who were working in Jollanamdo. The research instruments used in this study was 'Needs of In-service Education questionnaire'. 305 collected Data were analyzed with the frequency analysis, $x^2$-test. The conclusions were as follows; First of all, the most important motives for the school nurses to participate in-service education are the enhancement of their specialties on teaching profession, self-realizations as educators, and improvement of health teaching skill. However, the motives to obtain the skill for school management or to obtain a high rank qualification and promotion are quite low. School nurses are generally satisfied with duration, time, place of in-service education, But they are not satisfied with contents of in-service education, professional specialist and understanding of real educational situation of the instructors. On the urgent problem of school nurses, promotion of health teaching skill was highest in the rank, and establishment of firm educational philosophy and a sense of teaching profession, proceed to university and graduate school ranked next, respectively. Second, the need of a school nurses on in-service education direction ranked the application of teachers' character and need, practicable and concrete educational programs, planning of school health development, reinforcement of health education, expansion of practical knowledge and on reflection thought, respectively. The need of a school nurses on in-service education contents(major part) ranked health education, health promoting program of student, knowledge and practice of practical medicine and oriental medicine, consultation process, health education of advanced country, respectively. The need of in-service education supervisory organization, the need for a cities provinces educational office was highest in the rank. The need of in-service education type, duty training ranked high, and abroad training, qualification training, general training ranked next. the need for specialist for lecturer of in-serve education ranked among the highest, along with school nurses and university professor. The need of school nurses on education method(duplication answer), need for conference and discussion teaching was highest in the rank. The need on evaluation method, evaluation through a examination ranked the highest. On the needs of in-service education times, need for vacation during the winter and summer was the highest. As for the duration, 31 to 60 hours in duration of in-service education was need most, and most school nurses need cities and provinces in-service training institute as the location of in-service education. On the organization size, need for 21 to 30 people was the highest, where as need for 41 people was relatively low. Lastly, on the problem of in-service education for school nurses, lack of opportunity of in-service education for school nurses was highest in the rank, and improperness of in-service education contents and method, lack of incentive ranked next, respectively.

• Convergence Security Journal
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• v.17 no.5
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• pp.41-47
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• 2017

The Marine Environment Observation Information System supplies oceanographic information elements such as water temperature, chlorophyll, float, etc. based on satellite images to consumers. The data produced by the Korean marine environmental observatories are located in the coastal areas of Korea. But if the range is too far from a particular area of interest, due to distance or spatial constraints, the accuracy and up-to-dateness of the data can not be relied upon. Therefore, it is necessary to perform fusion and complex operation to solve the difference between the field observation and the marine satellite image. In this study, we develop a system that can process marine environmental information in the user's area of interest in the form of layered character (numeric) information considering the readability and light weight rather than the satellite image. In order to intuitively understand satellite image information, we characterize (quantify) the marine environmental information of the area of interest and we process the satellite image band values into layered characters to minimize the absolute amount of transmitted / received data. Also we study modular location-based interest information service method to be able to flexibly extend and connect interested items that diversify various observation fields as well as application technology to serve this.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1479-1488
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• 2022

Accidents in which oil spills occur intermittently in the ocean due to ship collisions and sinkings. In order to prepare prompt countermeasures when such an accident occurs, it is necessary to accurately identify the current status of spilled oil. To this end, the Coast Guard patrols the target area with a fixed-wing airplane or helicopter and checks it with the naked eye or video, but it was difficult to determine the area contaminated by the spilled oil and its exact location on the map. Accordingly, this study develops a technology for direct ortho-rectification by automatically geo-referencing aerial images collected by the Coast Guard without individual ground reference points to identify the current status of spilled oil. First, meta information required for georeferencing is extracted from a visualized screen of sensor information such as video by optical character recognition (OCR). Based on the extracted information, the external orientation parameters of the image are determined. Images are individually orthorectified using the determined the external orientation parameters. The accuracy of individual orthoimages generated through this method was evaluated to be about tens of meters up to 100 m. The accuracy level was reasonably acceptable considering the inherent errors of the position and attitude sensors, the inaccuracies in the internal orientation parameters such as camera focal length, without using no ground control points. It is judged to be an appropriate level for identifying the current status of spilled oil contaminated areas in the sea. In the future, if real-time transmission of images captured during flight becomes possible, individual orthoimages can be generated in real time through the proposed individual orthorectification technology. Based on this, it can be effectively used to quickly identify the current status of spilled oil contamination and establish countermeasures.

• 지역과문화
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• v.7 no.2
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• pp.113-132
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• 2020

This study explored ways to make tourism resources based on the historical significance and major legacies of Yesan Imjon Fortress and Hongju Juryu Fortress, the center of the war where the core leadership of Baekje Restoration War was located. After the collapse of Baekje, it looked at the process of the restoration war centered on Imjon Fortress, the main characters, Imjon Fortress and Juryu Fortress, and the legends related to the restoration war. The tourism value of Baekje Restoration War is highlighted in terms of location identity and dark tourism. After reviewing cases of similar characteristics to the Baekje Restoration War, the method of tourism resourceization was presented. The elements of resourceization include characters, battles, relics, places, and name legends. Reproduction strategy, experience strategy, hard branding strategy and soft branding strategy were presented. As an example of the reenactment strategy, the Baekgang Battle reenactment event was presented. Experience strategies include walking and Baekje pottery. As for the hard-branding strategy, installation of sculptures of major characters and upgrading of tourist information signs were suggested. Soft branding strategies raised the need for logo marks, catch phrases, character products, video contents, and story maps through the branding of fortresses related to the Baekje Restoration War.

• Journal of Korean Library and Information Science Society
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• v.54 no.1
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• pp.1-24
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• 2023

The history of modern libraries in Korea is less than 150 years. Nevertheless, there are various issues about when the word library appeared, how it was transformed, and the name and overall appearance of the library opened by the Busanpo branch of the Nihon Kodo-kai during the enlightenment period. Therefore, this study analyzed and argued many issues. As a result, it was found that the word library appeared in poetry collections, tombstones, and diaries from the early Joseon dynasty. Although it was widely held that the library was first introduced by Yu Gil-jun's 「Seoyugyeonmun, 1895」, it appeared in Lee Hun-young's 「Iisajipryak」 and was also introduced in 「Hanseongsunbo, 1884」. And the first name given to the facility was Kodo library, which was opened by the Busanpo branch on October 10, 1901. Book club, reading club (library), Busan(Busan district) library, Kodo bookstore, Kodo-kai library, etc. which are described in many documents are all errors. The location of the library was a temporary house on a leased site in Seosanhajeong of Yongdusan mountain. And it is presumed that it has secured about one room and 1,000 Japanese and Western books, and provided fee-based services to Japanese residents. Although the Kodo library is not the first public library established by a Korean, it is undeniable that it was the first public library to exist in Korea. Therefore, when defining the character of the Kodo library, it is necessary to have a coolness and discernment beyond national emotions, historical conflicts, and ideological frames.

• Korean Journal of Heritage: History & Science
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• v.56 no.1
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• pp.208-223
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• 2023

This article was prepared for the purpose of reviewing maintenance plans and strategies for designating the celadon kiln site in Banam-ri, Gochang, a monument designated by the city and province as a historical site. Prior to the discussion, the high academic potential of this site, which is attracting attention as a main point of early celadon main point, was explained, and expectations for the future designation of the monument were reviewed. Next, the current status of preservation and maintenance plans of the celadon kiln site in Banam-ri, Gochang were examined. In particular, the current preservation situation was reviewed through an on-site survey on how the ruins, which have not been designated as a monument, should be maintained for historical designation in the future. Above all, it was argued that it was necessary to conduct excavation and literature surveys to clarify the characteristics of the ruins, investigate the surrounding areas, improve information facilities for visitors, and carry out promotion in connection with them. Finally, the definition of historical sites and the status of historical designation of ceramic kilns, along with the strategies necessary for designation, were presented. In particular, the examples of the existing historical designated celadon kiln site in Dotong-ri, Jinan, and Buncheong Kiln Site in Undae-ri, Goheung were reviewed, and three types of excavation surveys, literature surveys, and academic conferences were presented as the target directions for historical designation. The result of the excavation survey is the basis for suggesting that it has cultural property values with completeness, authenticity, and identity. The literature survey is the basis for supplementing the historical and cultural character of the remains that have not been revealed by excavation. The academic conference explained that it is an opportunity to understand the nature and value of cultural assets, such as the location of cultural assets, the status of relics, and events related to relics.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.5
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• pp.217-228
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• 2023

Video instance segmentation is an intelligent visual task with high complexity because it not only requires object instance segmentation for each image frame constituting a video, but also requires accurate tracking of instances throughout the frame sequence of the video. In special, human instance segmentation in drama videos has an unique characteristic that requires accurate tracking of several main characters interacting in various places and times. Also, it is also characterized by a kind of the class imbalance problem because there is a significant difference between the frequency of main characters and that of supporting or auxiliary characters in drama videos. In this paper, we introduce a new human instance datatset called MHIS, which is built upon drama videos, Miseang, and then propose a novel video data augmentation method, CDVA, in order to overcome the data imbalance problem between character classes. Different from the previous video data augmentation methods, the proposed CDVA generates more realistic augmented videos by deciding the optimal location within the background clip for a target human instance to be inserted with taking rich spatio-temporal context embedded in videos into account. Therefore, the proposed augmentation method, CDVA, can improve the performance of a deep neural network model for video instance segmentation. Conducting both quantitative and qualitative experiments using the MHIS dataset, we prove the usefulness and effectiveness of the proposed video data augmentation method.