• Fire Science and Engineering
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• v.31 no.3
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• pp.63-72
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• 2017

This study fabricated a low-voltage 10 circuit distribution board based on the KEMC (Korea Electrical Manufacturers Cooperative) 2102-610 standard and performed a characteristics assessment of the developed 10 circuit distribution board to secure product stability. The developed 10 circuit distribution board is designed to have the characteristics of insulation materials, as well as resistance to corrosion ultraviolet radiation and mechanical impact. The developed distribution board is fabricated to have an appropriate protection class of enclosure, electric shock prevention and protection circuits, switchgear and its components, internal electrical circuits and connectors, external conduct terminal, insulation characteristics, temperature rise test, heat resistance, etc. The developed 10 circuit distribution board consists of a single phase circuit and 3-phase circuits. It is possible to measure in real time the leakage current generated from the load distribution line by installing a sensor module at the load side of each of the branched switchgears. In addition, it is possible to increase a circuit according to the use and purpose of the load and to also manage and check the load in real time. Temperature rise tests were performed on the developed 10 circuit distribution board at 18 places including the inlet connection, main circuit and distribution circuit bus bars and bus bar supports, etc. The highest temperature of $65.3^{\circ}C$ was measured at the R-Phase of the connection of the MCCB power supply for the branch circuit bus bar and a temperature rise of $61.6^{\circ}C$ was measured at the T-Phase of the load side. When applying thermal stress to an MCCB for 6 hours at $180^{\circ}C$ using a heat resistant experimental device, it was found that the actuator lever was transformed and moved in the tripped state.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.223-224
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• 2004

고준위폐기물 혹은 사용후 핵연료의 처분용기 재질은 각 국의 처분개념과 처분공의 주위 환경에 따라 달라질 수 있다. 용기의 후보재질로는 탄소강, 스텐레스 강, 구리, 니켈, 티탄 혹은 이들의 합금이 주로 고려되고 있으나, 국내에서는 아직 선정되지 않았다. 국내 처분환경에서 이들 재질의 부식특성을 조사하고자 모의 화강암 지하수를 가해 만든 겔 상태의 경주 벤토나이트에 탄소강, 스텐레스 강, 구리 시편을 넣고, $70^{\circ}C$, 아르곤 분위기에서 530일 경과한 후 시편의 표면 변화 (그림 1) 및 무게 감소를 측정하였다. 철 부식시편은 검정색의 철 화합물 층으로 덮여 있었으며, 구리표면에는 노란색의 부식층이 형성되었는데, 이를 XRD로 분석한 결과 $Cu_2O$로 판명되었다. 그러나 $700^{\circ}C$에서 각각 0, 24, 96시간동안 예민화시킨 스텐레스 강 시편들은 모두 초기상태 그대로 광택을 유지하고 있었으며, XRD에서 다른 화합물의 형성을 발견할 수 없었다 (그림 2). 시편의 무게 감소가 균일부식에 기인한 것으로 가정하여 환산한 결과, 구리와 스텐레스 강 모두 0.3~0.4 $\mu\textrm{m}/yr$의 부식속도를 나타내었다. 그러나 구리는 부식생성물이 표면에 부착되어 있기 때문에 실제 부식두께는 이 값보다 더 클 것으로 생각된다. 용기가 초기 530일간과 같은 속도로 처분용기의 부식이 진행된다면 한국에서 기준처분 개념으로 삼고 있는 50mm 두께의 내부식성 외벽 금속용기는 적어도 만년이상 견딜 수 있을 것으로 추정된다. 한편, 검정색 부식층을 제거한 무게감소로부터 계산한 철의 부식속도는 구리의 약 30배에 해당하였다. 금속 재질의 정확한 부식 거동을 파악하기 위해서는 보다 장기간의 실험이 요구된다. 시험법 선정에 각계(규제기관, 학계, 발전소 현장 및 산업계 등) 전문가로부터 기술자문회의를 통하여 자문 의견을 받기로 하였다. 특히 현재 폐기물 인수 기술기준치가 설정된 국가의 시험법을 심층 있게 검토하기로 하였다.검토하기로 하였다. 혹은 수성주변 환경이 지배하는 산악이나 구릉지에서 흔히 나타나는 침엽수-낙엽활엽수의 혼합림 식생상태를 잘 대변해 주고 있는 것으로 판단된다. 끝으로, 의림지 호저 퇴적층 중에서 인위적인 교란흔적이 없는 암회색 유기질 니층에 대한 탄소연대측정 결과, 제1호공 12번 시료에서 950$\pm$40 years B.P을 얻었으며, 제3-1호공에서도 아래로 내려가면서 8, 10, 11번 시료에 대하여 500$\pm$30 years B.P, 650$\pm$30 years B.P, 800$\pm$40 years B.P의 연대측정 결과를 획득하였다. 이상과 같은 의림지 호저 퇴적층의 형성환경과 형성시기 연구를 통하여 의림지의 제방축조의 최초시기를 해석해 보면, 의림지의 제방은 적어도 과거 약 827년 전에서 866년 전에는 이미 축조되어 있었음을 알 수 있다. 과거 제천 일대에 살았던 옛사람들이 의림지 하류의 곡지중앙과 고기 충적선상지에 대한 관계용 용수조달의 필요성에 부응하여 상류부 곡지하천의 자연입지 환경을 최대한 이용하여 축조한 것으로 판단된다..준비하였다.전류를 구성하는 주요 입자의 에너지 영역(75~l13keV)에서 가장 높은(0.80) 상관계수를 기록했다. 넷째, 회복기 중에 일어나는 입자들의 유입은 자기폭풍의 지속시간을 연장시키는 경향을 보이며 큰 자기폭풍일수록 현저했다. 주상에서 관측된 이러한 특성은 서브스톰 확장기 활동이 자기폭풍의 발달과 밀접한 관계가 있음을 시사한다.se that were all low

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.189-198
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• 2009

As a part of an effort to minimize the polymerization shrinkage which is considered to be a major cause of failed bonds to tooth, newly designed 'Double LED system' was tested in the present study. Analyses were performed on the pattern of micro-leakage and the changes of strain which have occurred during the polymerization process. The results can be summarized as follows: 1. In the strain change, dramatic increase was observed with initiation of polymerization which was followed by subsequent gradual decrease with elapse of time in both the single LED system and double LED system. 2. The single LED system were shown to develop and maintain the maximum stress more than double LED system(p<0.05). 3. Less micro-leakage was found in the double LED system than in the single LED system(p<0.05). From the above-mentioned results, the double LED system can be a very useful tool in a sense of reducing polymerization shrinkage when compared to the single LED system. However, practical problems such as size of curing unit and its application method with its light intensity should be solved before its clinical application.

• Archives of design research
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• v.16 no.3
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• pp.161-174
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• 2003

Choice and use of color are very important field for designer. Present color sprang by central field of design business unlike past. Color is used mainly by three fields of sensitivity, administration, mind. But, do substantial design including all of three fields at use. Practical research field that is based on basic research when see as actuality of domestic color design is been behind real condition. Specially, color sensitivity field and color management field are very important field, it can speak that color name arid related area are most important among two. Because collar name includes sensitivity and color management. This research constructs correct data because investigate and analyze and search all compatible color names that is announced in existing or is recorded in public cosmopolitanly. As a result, it is to promise accuracy when produce creation of idea and result of design using color name. Examined laying stress on color that domestic data that is used in research is basis with Korean industrial Standard, connection literature, on-the-spot probe. International data investigated American ISCC-NBS to base. Other abroad color name data examined official data of each country all systematically with Japan, Europe. Findings about 11,000 basis color names and 33,000 application color names sorted collection. Collection method and classification system follow in international standard and arranged for user's tile convenience. Also, use frequency did laying stress on Munsell that is high color system so that can aid in industrial design business. Improved to write all international standard color values sue as RGB, CMYK, XYZ and can be applied all in each field of design. Is applying and get along with continuation improvement and development in homepage of present KIDP, it may become more worth research.

• Journal of the Korean Society for information Management
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• v.26 no.2
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• pp.27-41
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• 2009

With explosive growth in the area of the Internet and IT services, various types of digital contents are generated and circulated, for instance, as converted into digital-typed, secure electronic records or reports, which have high commercial value, e-tickets and so on. However, because those digital contents have commercial value, high-level security should be required for delivery between a consumer and a provider with non face-to-face method in online environment. As a digital contents, an e-ticket is a sort of electronic certificate to assure ticket-holder's proprietary rights of a real ticket. This paper focuses on e-ticket as a typical digital contents which has real commercial value. For secure delivery and use of digital contents in on/off environment, this paper proposes that 1) how to generate e-tickets in a remote e-ticket server, 2) how to authenticate a user and a smart card holding e-tickets for delivery in online environment, 3) how to save an e-ticket transferred through network into a smart card, 4) how to issue and authenticate e-tickets in offline, and 5) how to collect and discard outdated or used e-tickets.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.1
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• pp.71-86
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• 2013

This study was carried out to find the changed contents and details of the ponds at Jondeokjeong area in the Changdeok Palace, where was modified during the reign of King Gojong(高宗, 1863~1907), and considered the internal context through the diachronic views about royal garden building in the Joseon Dynasty. The results were as belows. First, this study found that the transformed time of the ponds at Jondeokjeong area was the 21th year of King Gojong(1884) based on the pictures taken in the last half of the 19th century and the records of "Gojongsilrok(高宗實錄: Annals of the King Gojong)". Second, this study also found that the remodeled ponds at Jondeokjeong area by King Gojong were followed the landscape of Geoncheong Palace(乾淸宮) and Hiangwon-pond(香遠池) in Gyeongbok Palace because the remodeled ponds of Jondeokjeong area had the spatial organization similar to Hiangwon-pond. Third, the bridge of remodeled ponds at Jondeokjeong area was utilized as the expedient to expand the function of rear garden, which combines the areas of Yungyungdang(演慶堂) and Jondeokjeong. This was the same method that Konchunggung(乾淸宮) in Gyeongbok Palace had occupied the whole area through the Chui-hiang bridge(醉香橋) which connects to the Hiangwonjeong(香遠亭). Fourth, ponds at Jondeokjeong area and Hiangwonjeong that were created during the year of King Gojong promised the use of Yungyungdang and Konchung Palace, and reflected the statuses of the two building-blocks. Lastly, this study concluded the remodeled Jondeokjeong ponds were not only to create the necessary spaces of the landscape for King Gojong, but also to build the space on the context of Huwonjeongdang(後苑政堂: political structure in rear garden), which has been passed down from their ancestors.

• Journal of Korea Water Resources Association
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• v.48 no.8
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• pp.605-612
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• 2015

The purpose of this study is to compare and analyze design flood estimation methods which are the basis for determining the size of a flood control structure. The result from a flood frequency analysis which is considered as the best way for estimating design flood was assumed as a true value, and a method of simulating runoff and performing frequency analysis of the maximum discharge data were compared with a design storm method. For a comparative analysis of design flood estimation, seven basins (Namgang reservoir basin, Soyanggang reservoir basin, Andong reservoir basin, Seomjingang reservoir basin, Imha reservoir basin, Chungju reservoir basin, Hapcheon reservoir basin) were selected. For the Seomjingang, Hapcheon, and Imha reservoir basins, the method proposed in this study showed better results, whereas the conventional method showed better results for the Namgang, Soyanggang, and Chungju reservoir basins. The results show that the conventional method (the design storm method) is not the best way for estimating design flood and the proposed method can be used as an alternative for small basins.

• Korean Journal of Ichthyology
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• v.12 no.3
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• pp.215-222
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• 2000

Fish fauna of the coastal waters off Taean, Chungchyungnam-do, Korea, was investigated from May 1996 to July 1999. The specimems collected from the three localities were identified into 73 species belonging to 63 genera and 40 families. Of them the largest group was order Perciformes, comprising 35 species and 16 families, and showed 47.9% in total number of species. Chasmichthys gulosus and C. dolichognathus were commonly found from the st. 1, Sebastes schlegeli and Hexagrammos otakii, from the st. 2 and Cynoglossus joyneri, Acanthopagrus schlegeli, Pagrus majar, Chirolophis wui and Pholis fangi from the st. 3 of sampling localities. Porocottus sp. is described on the basis of 2 specimens collected from the st. 1 of sampling localities. The species was distinguished from all the other members of the genus by the following combination of characters: united dorsal fin, scales on trunk above lateral line, cirri on anterior part of lateral line.

• Economic and Environmental Geology
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• v.39 no.4 s.179
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• pp.403-416
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• 2006

Magnetic method is rapid, cheap and simple geophysical exploration technique, and has wide range of applications such as resources prospecting, geological structure investigation and even geotechnical and environmental problems. Especially, aeromagnetics gives fundamental and useful geoscientific data fnr not only assessment of potential resources, but also national land planning. Magnetic method, perhaps the oldest geophysical technique, was relatively early introduced into Korea. Documents during Japanese occupation says that magnetic method was used for exploring metallic ore deposits and hot spring, and that a geomagnetic observatory was operated. From mid 1950's, after Korean War, magnetic explorations for natural resources such as metallic ore, uranium, coal, and groundwater were intensively executed for industrialization. Apache aeromagnetic survey project during $1958{\sim}1959$ and its ground follow-up surveys are typical and important cases in those days. Magnetic survey techniques were rapidly advanced during 1970's and 1980's with improvements of instruments, growth of geophysical manpower, and availability of computers. The national aeromagnetic mapping project by KIGAM in 1981 showed the improved technical capability of those days. Decline of mining industry since mid 1980's moved the exploration objects from traditional resources to new ones such as groundwater and geothermal resources, and applications to investigation of geological structure were revived. Recently appeared applications such as natural hazard assessment, and engineering and environmental studies increased the magnetic method's utility in the realm of exploration.

• Journal of Korea Water Resources Association
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• v.37 no.3
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• pp.249-255
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• 2004

To investigate the return flow ratio of irrigation water, lots of observations were made during the irrigation periods in 2003 crop year. This Area is a portion of Dae-Am pumping station basin which is located in Changryung-gun, Gyeongnam province. A water balance analysis was performed for a paddy field in Dae-Am pumping station in the Nakdong river basin, which is constructed for irrigation water supply. Daily rainfall data in the this area were collected and irrigation water flow rate, drainage water flow rate, infiltration and evaportranspiration were measured in field area. Irrigation water flow rate and drainage water flow rate were continuously observed by water level logger(GTDL-L10) during the growing season. The infiltration and evaportranspiration were measured by cylindrical 300mm depletion meter and cylindrical 200mm infiltrometer, respectively. Total irrigation and drainage flows were 654.7mm and 281.2mm in 2003. Total infiltration and evaportranspiration were 36.0mm and 160.0mm respectively. The mean of the daily evaportranspiration rate was 4.3mmm/d. The prompt return flow and retard return flow ratio were 43.0％ and 5.5％, respectively. Total return flow ratio was 48.5％. Therefore, it can be concluded that the amount of irrigation water was much higher than design standard or reference in this study. It means that this was caused by the inadequate water management practice in the area where water was oversupplied on farmers' request rather than following sound water management principles, and design standard should be changed in the future.