• KEPCO Journal on Electric Power and Energy
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• v.3 no.2
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• pp.79-88
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• 2017

In this paper, the wind tunnel test for the measurement of aerodynamic characteristics of transmission conductors with asymmetric sections is described. A single conductor model and bundled conductor models with ice accreted shapes are tested both in steady and turbulent flow, and the aerodynamic coefficients are acquired. Transmission conductor galloping is a kind of wind-induced vibration which is characterized by primarily vertical oscillation with a very low frequency and a high amplitude. It is well known that transmission conductor galloping is generally caused by moderately strong, steady winds when a transmission conductor has an asymmetric cross-section shaped by accreted ice. Galloping should be considered from the design stage of overhead lines because it can cause severe wear and fatigue damage to attachments as well as transmission conductors. It is reported that there have been normally 20 events of galloping per year in Korea, which may be followed by serious consequences in the electric power system. Therefore, this research is performed to measure aerodynamic characteristics of ice accreted transmission conductors to understand and control transmission conductor galloping so that it would help to prevent unexpected failures and reduce the maintenance costs caused by galloping.

• Journal of the Korean Institute of Gas
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• v.19 no.1
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• pp.6-11
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• 2015

This paper is to study the examples for rubber damage and weaken reliability of timing belt, constant velocity joint boot and weather strip in vehicle. The first example, when the service man replaced the new timing-belt of rubber material, he assembled the belt that was weaken it's contact surface because of material transform. He knew the abnormally tearing failure by friction action between belt and sprocket. The second example, it certified the fact that the grease is leaked out boot protecting of constant velocity joint by split of rubber surface because of durability badness. The third example, the weather stripe took the minutely tearing because of damage produced the material transform by crack of chemistry change. It certified the production phenomenon of a tiny noise by coming with outside air because of overlapped the rubber of weather stripe when driving after closing the door. Therefore, the driver must always manage the rubber system part of vehicle.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.2
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• pp.132-139
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• 2016

The progressive attrition of teeth is a normal process by aging. However, excessive tooth wear with decreased vertical dimension of occlusion and collapse of occlusal plane may cause pathologic pulpal condition, occlusal disharmony, functional disorders and esthetic problems. The change of vertical dimension is required in case that there is no sufficient clearance for restoration or in case that the occlusal relationship is modified. For gaining the vertical dimension, a careful diagnosis is essential prior to starting the restoration treatment. After evaluating adaptation of neuromuscular system of patient during provisional phase, the final restorations can be fabricated. In this case, a 78 year old male with severely worn down dentition was treated. To improve the esthetic appearance and to achieve the ideal occlusal relationship, the full mouth rehabilitation with minimal increase of vertical dimension is planned and diagnostic wax-up was performed at the increased vertical dimension. After evaluation of provisional restorations for 12 weeks, final restorations were fabricated and routine clinical assessments were made. After 1 year, the restorations with newly established occlusal scheme are well maintained without significant complications and esthetically and functionally satisfactory results were obtained.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.4
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• pp.477-482
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• 2010

In a case of multiple posterior teeth loss, antagonistic teeth extrude to the edentulous space and compensatory occlusion on the remained anterior teeth leads to occlusal trauma. Extrusion of antagonistic teeth breaks down occlusion plane and loss of posterior support bring about severe wear of remained teeth. In this situation, it is needed to restore remained teeth and edentulous space by increasing vertical dimension to obtain prosthodontic rehabilitation space and to correct occlusion plane. In this case report, the patient had a masticatory problem with loss of posterior teeth support and an esthetic problem of shortened anterior teeth. Before the tooth preparation for the prosthodontic restoration, the patient used removable device for 2 months to increase vertical dimension reversibly. After that, he got provisional fixed restoration with irreversible tooth reduction and used it for 3 months. It had spent 5 month to evaluate the adaptation state on final restoration with incresed vertical dimension. The increasing amount was 3 mm, which was relatively in less degree and masticatory system adapted to the increased vertical dimension without any pathologic changes. Final restoration was made to have equal-intensity contacts on all teeth in a verifiable centric relations and immediate disclusion of all posterior contacts the moment the mandible moves in any direction from centric relation. In addition, metal occlusion surface on posterior teeth was applied to prevent excessive muscle activation, occlusal trauma and the porcelain fracture.

• Journal of the Korean Society of Costume
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• v.22
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• pp.159-176
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• 1994

This study's purpose is to find the ancient costume of the folk song's words on Dunhuang manuscripts in the background wass-carvings sculptures and several art works. Dunhuang had played the part of major route between ancient China and Europe. It is located on kam-suksong the west of China. 1. In the aspect of costume arrangement hair Styling is represented by Naegagyo, Wangyesa, Kyongburak, Bonkwyun, Pogurak, Chonsonja, Namgaja, Tongson-ga, Ojesa, Chanboja in Dunhuang manuscripts. tugue is sim-ilar to Sabyokkwanja in Naegagyo as of that time these kinds of Kwan-ja was very popular. It was told that emperor's wife concubine and maid of honor would wear kwnaja favorably. And the kinds of Tugeu is PuyongKwyunkye, Aangunkye, Chunkye from Kyuwanjon except Sangunkye, Ounkye in Dunhuangsa. 2. Jangdaegy is guoted from Kyuw-anjon -A series of the chinese history book-tells us about women's make-up . The narmes of make-up are Hongjang Unjan--g, Yiljang chwejang, Tam-ajang Murgjang, Sanagjang, Light-make up are referred in Naegagyo is included as packjang Besides we can find other make-up skills Huphwaro and Rujang from the Kaewonch onbon-wisa which was Yangkwibi's episodes. We can find the a corpus of song's words about cosmetic custom in Kor-ea. Which is 'Haecho' folk song in the souther-en costal regions 'Jinggum' folk song in Kim-hae regions and so on.... It's words is similar to Dunhuangsa in China. 3. Bichun inherited to China with India Bud-dism art in the middle of Dunhuang wall-pain-tings is one of the important Buddist saint. Sometimes it is painted with Giakchun Its arms of fly-dnacing in heaven with colored belt on body has almost the form of play on the musical instrument, We can see seasily the form in the painting of Buddist ser-mon. It was progressed and changed with the background of chinese traditional culture. When Dang's period came the color was chan-ged lighting dark blue has rhythmical and viv-id power of life. 4. Among the corpus of song's words which express the singers' system and rites of their tradition or habits. Dunhuang manuscripts des-cribes on behalf of the folk song's words in tra-ditional costume. This is following: (1) Naegagyo o sabyokwanja o Chyrasam o Rashang (2) Wangyesa o Sokryugun o Costume for fisher man (3) Bungajang of the chanboja o Ajang (4) Pongkwyun o Chongui (5) Tongsongs o Junofore (6) Namgaja o thin-Rasam (7) Yuchungnang o Hongsam o Sokryugun : The color of red costume (8) Kyongburak o Hongrasam o Sokryugun : Costume for charming woman Therefore traditional costume could be extracted according to the Dunhuang folk song's words out of culture such as learning rit-es three-obedience four-virtues and in-struction. As the same time it reflects ancient China's characteristics directly. I would endeavor to development for the history of the costume furher creative design and participat-ed in research activity with concerns forward continuously.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.1
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• pp.15-20
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• 2002

The Hydroxyethyl methacrylate(HEMA) was developped in 1960's and later the use of contact lenses increased. At present more and more people use RGP contact lenses. Due to the wide range of optical corrections available and due to their high oxygen transmission Japanese and Korean people like them. Nevertheless one of nine CL users(beginners) stopped wearing the CL within the first year. We conducted a survey to evaluate the level of patient compliance in lens care and maintenance and to assess practitioner knowledge of contact lens information. Generally 6% of contact lens wearers drop out per year. The aim of this research was to find out what opticians can do to reduce the drop-out rate by getting information on handling, on general data of the patient and on optical prescription. Lens wearer were asked to complete a 10 question survey that focused on lens care-wear modality, lens replacement, storage, symptoms and case disinfection. There were total 180 participants in the study. Most of contact lens wearers have an inadequate understanding of contact lens care system. Therefore, it is important that contact lens specialists place more emphasis on practitioner education about general contact lens fields and reinforce patient education during the dispensing visit.

• Journal of the Korean Society of Radiology
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• v.14 no.4
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• pp.385-390
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• 2020

In the present, external environmental factors affect human health. In particular, the most important issue is fine dust in these days. Because fine dust is inhaled through the human respiratory system is known to be harmful to health. Tunnels for cars and people can also be easily seen around us. This study, the amount of scattering radiation was measured for walkable tunnels about dust. For the measurement method, dust and radiation dose in the tunnel were measured on good weather (fine dust level: 0 ~ 30 ㎍/㎥) and normal day (fine dust level: 0 ~ 80 ㎍/㎥). The measurement resulted in an increase of 10~20 % of dust in the center of the tunnel on a good weather day and an increase of 20~30 % of dust in the center of the tunnel on normal weather. On the other hand, the results of tunnel measurement of radiation dose increased by 10~20 % at the center of the tunnel non-depending on the weather. As a result, pedestrians should pay attention to scattering dust and scattered radiation while moving through the tunnel. Therefore, it is recommended to wear a filter mask of PM2.5 or less during frequent tunnel walking.

• Journal of the Korea Safety Management & Science
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• v.22 no.3
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• pp.1-8
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• 2020

The desulfurizers facility is cylindrical shape. To operate properly it needs nozzles cleaned, get rid of lime adhesion and sludge, repair the wear and corrosion of facility regularly. For this purpose, workers shall access the ceiling or vertical wall at high place. Ordinary scaffoldings such as steel pipe scaffolding or system scaffolding have been using so that workers can access them. With these ordinary scaffoldings, openings around cylindrical wall are inevitable which make workers can expose always to the risk of falling. The purpose of this study is to develop customized scaffolding to minimize the openings to prevent workers form falling during maintenance it. It consists of a hexagonal central tower and six trapezoidal outer towers. And the bracing among the towers have connected each other for self-standing and for maintaining the structure of towers. Span decks, the circumference footstools, steps, etc. are laid on each floor. The safety is reviewed by structural analysis and performance test. With this study, openings each floor of this scaffold are removed. The gap between the cylindrical wall and the edge of the work stage is approximately 100 mm. Therefore, we expect that workers can work safely and efficiently.

• Journal of the Korean Society for Library and Information Science
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• v.45 no.1
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• pp.125-147
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• 2011

Recently, with a high demand for the construction and remodeling of libraries, and the rapid increase in the number of libraries during the last two years, the concern and need for library goods is also increasing sharply. The purpose of this study is to develop a new classification scheme of library goods by clarifying the terminology which could provide an accurate information on library goods and allow for their smooth circulation. In this study, library goods are defined as all kinds of products required for effectively collecting, organizing and providing services with library materials, and classified into library equipments and library supplies. The term, library equipment is principally used for those things that do not wear out within a certain time period, such as furniture and machinery. Library supplies refer to those things that are expendable. As the terminology is clarified, the classification scheme can be further refined. Library equipment, for example, can be classified as furniture, library system solutions, and computers and multi-media tools. Library supplies can be classified into library organization and repair supplies, sign systems, and miscellaneous articles. Finally, six major categories which include 117 different items are presented.

• KIPS Transactions on Computer and Communication Systems
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• v.9 no.8
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• pp.171-180
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• 2020

Smart Factory consists of digital automation solutions throughout the production process, including design, development, manufacturing and distribution, and it is an intelligent factory that installs IoT in its internal facilities and machines to collect process data in real time and analyze them so that it can control itself. The smart factory's equipment works in a physical combination of numerous hardware, rather than a virtual character being driven by a single object, such as a game. In other words, for a specific common goal, multiple devices must perform individual actions simultaneously. By taking advantage of the smart factory, which can collect process data in real time, if reinforcement learning is used instead of general machine learning, behavior control can be performed without the required training data. However, in the real world, it is impossible to learn more than tens of millions of iterations due to physical wear and time. Thus, this paper uses simulators to develop grid sortation systems focusing on transport facilities, one of the complex environments in smart factory field, and design cooperative multi-agent-based reinforcement learning to demonstrate efficient behavior control.