• Journal of the Korean Society of Safety
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• v.25 no.2
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• pp.35-40
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• 2010

Explosion limit and flash point are the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, in order to predict upper explosion limits(UEL), the upper flash point of n-alcohols were measured under the VLE(vapor-liquid equilibrium) state by using Setaflash closed cup tester(ASTM D3278). The UELs calculated by Antoine equation using the experimental upper flash point are usually lower than the several reported UELs. From the given results, using the proposed experimental and predicted method, it is possible to research the upper explosion limits of the other flammable substances.

• Journal of the Korean Society of Safety
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• v.26 no.4
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• pp.59-64
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• 2011

Explosion limit and flash point are the major combustion properties used to determine the fire and explosion hazards of the flammable substances. In this study, in order to predict upper explosion limits(UELs), the upper flash point of n-alkanes and aromatic compounds were measured under the VLE(vapor-liquid equilibrium) state by using Setaflash closed cup tester(ASTM D3278). The UELs calculated by Antoine equation and chemical stoichiometric coefficient tusing the experimental upper flash point were compared with the several reported UELs. From the given results, using the proposed experimental and predicted method, it is possible to research the upper explosion limits of the other flammable substances.

• Journal of Korean Medical classics
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• v.20 no.2
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• pp.231-268
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• 2007

재일본규주황한의학적전통의학지전신취시중국전통의학적지식(在日本叫做皇漢醫學的傳統醫學之前身就是中國傳統醫學的知識). 16세기이래(16世記以來), 일본불단수도이개조중국의학적최신성과(日本不斷收到而改造中國醫學的最新成果), 동양원류우부동홍류적한방의학체계점점형성적과정전후(同樣源流又不同洪流的漢方醫學體系점점形成的過程前后), 출현료4개학문유파(出現了4個學問流派). 저취시(저就是)"후세파(后世派)"."고방파(古方派)"."절충파(折衷派)"."고증파(考證派)". 소우호세파(소于호世派), 논자이경재대한한의학원전학회지적제19권3호상보고료(논者已경在大한한의학原典학회紙的第19卷3호上보告了), 본논문시연속적연구성과(本논文是연속的硏究成果). 종이재본논문상(종而在本논文上), 이한국적이정환(以한국的李政桓), 백유상(白裕相), 정창현등적연구여중국양영적연구위기초(丁彰炫等的硏究與中國梁嶸的硏九爲基礎), 요개략지보고일본의학방면상적‘고방파’(要槪略地報告日本의학方面上的'古方派'). "고방파"지칭부정근세송명의학이지지지한대장중경적"상한잡병론"지일본의가("古方派"指稱否定近世宋明醫學而只支持漢代張仲景的"傷寒雜病論"之日本醫家). 일반"상한론"전파우일본적실정시대(一般"傷寒論"傳播于日本的室町時代), 명응년간(明應年間)(1492${\sim}$1500)판정운재명유학후(阪淨運在明留학후), 타회도일본적시후(他回到日本的시候), 종명수입(종明수入)"상한잡병론(傷寒雜病論)", 이후일본후세한의칭송료이관동지역적영전덕본(以후日本후世漢醫칭송了以關東地域的永田德本)(1513-1603)위(爲)"고방파적선구자(古方派的先구者)". 도강호시대재일본학술계출현료복고사조(到江戶時代在日本學術係出現了復古思潮). 이등인제(伊藤仁劑)(1627${\sim}$1705)앙망료유학적경전(仰望了儒學的經典), 이차적극지주장료의학적복고(而且積極地主張了醫學的復古), 이후적생조래(以후荻生組徠)(1666${\sim}$1728)대우복여성인적학문부단노력(對于復與聖人的學問不斷努力). 인차복고적학문재덕천시대성위일대학파(因此復古的學問在德川時代成爲一代學派), 18세기상반기시전성시기(18世紀上半期是全盛시期). 주요의가시명고옥현의(主要醫家是名古屋玄議)(1628${\sim}$1696), 후등양산(後藤양山)(1659${\sim}$1733), 산협동양(山脅東洋), 병하천민(병河天民)(1679${\sim}$1719), 송원유악(松原維嶽)(1689${\sim}$1765), 향천수암(香川修庵)(1683${\sim}$1755), 타문복고적유학영향도흔다의학방면(他문復古的儒學影향到흔多의학方面). 중요의가길익동동(重要醫家吉益東洞)(1702${\sim}$1773)도후대피평위고방적'태두'(到后代被평위古方的'泰斗'), 동시'마귀'(同시'魔鬼'). 인차본논문소우황한의학지중"후세파"여반대후세파적"고방파"(因此本論文소于皇漢醫學之中"后世派"與反대后世派的"古方派"), 통과학파명칭여역사지위(通過學派名稱與歷史地位), 주요의가적생애(主要醫家的生涯), 학술적요지(學術的要旨), 저서등(著書等), 이연구병보고타문적학문주장(以硏究병報告他們的學問主張). 이차진저차궤회(而且진저次机회), 상회고아문한의학연착여하역사적궤적(想回고我문韓醫學沿着如何歷史的軌跡).

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.3
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• pp.273-279
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• 2007

Probabilistic Risk Assessment considering statistically random variables is performed for the preliminary design of an Arch Bridge. Component reliabilities of girders have been evaluated using the response surfaces of the design variables at the selected critical sections based on the maximum shear and negative moment locations. Response Surface Method (RSM) is successfully applied for reliability analyses lot this relatively small probability of failure of the complex structure, which is hard to be calculated by Monte-Carlo Simulations or by First Order Second Moment method that can not easily calculate the derivative terms in implicit limit state functions. For the analysis of system reliability, parallel resistance system composed of girders is modeled as a parallel series connection system. The upper and lower probabilities of failure for the structural system have been evaluated and compared with the suggested prediction method for the combination of failure modes. The suggested prediction method for the combination of failure modes reveals the unexpected combinations of element failures in significantly reduced time and efforts, compared with the previous permutation method or conventional system reliability analysis method.

• Informatization Policy
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• v.24 no.3
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• pp.42-66
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• 2017

This study investigated the ecological change of public software industry, comparing the pre and post structure of industry network based on the application of the regulation restricting large company participation in public software market. For this purpose, we used big data of the software market from Korea Public Procurement Service and used the SNA(Social Network Analysis) methodology which is being actively used in the area of social science recently. Finally, we highlighted the contribution of open public data. By analyzing order and contract data of the public software industry for 3 years - from 2013 to 2015 - we found out two main things. First, we observed that Power Law distribution had been going on in the public software industry, regardless of the external impact of regulation. Second, despite the existence of such Power Law distribution, we also observed the ecological change of industry structure from year to year. We presented the implication of such findings and discussed the advantage of open public data as the original motivator of this study.

• Journal of Korean Historical Folklife
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• no.33
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• pp.359-384
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• 2010

The studies on Daedonggye(大同契), by this time, have been mainly researched focusing on the ruling system of country villages related to 'King(王)-local governor(守令)-noble family(士族)' in Chosun Period. The result of it is that it made a great contribution to reveal the operation of country society and substance of the ruling class but made it wholly lacking studying on the organization of Daedonggye in fishing villages especially and the social structure after the opening of ports. The residents in Noryeokdo have operated Daedonggye for about 80 years from 1925 up to now. Anyone who is a householder in Noryeokdo has been a participant in a member of it. The reason is that the participation in Daedonggye is the most basic requisite to lead the community life of the fishing village. It was investigated in this study that the residents operated their Daedonggye in what way in the 20th century and what motive made them keep it prolonged for a long time up to the 21th century.

• The Journal of the Petrological Society of Korea
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• v.6 no.3
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• pp.166-184
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• 1997

The Wondong caldea is a deeply eroded structure that offers spectacular exposures through the core and margins of a resurgent caldera. The Wondong Tuff and the postcollapse intrusions range from medium-silica rhyolite to rhyodacite in composition and the postcollapse lava and tuff, preresurgent and resurgent intrusions also range from medium-silica rhyolite to an-desite, which jump to gap dacite composition. The continuous compositional zonations generally define a large stratified magma system in the postcollapse and resurgent magma chamber. Isotopic and trace element evidence suggest that the compositional zonations might have resulted from the differentiations from crystal fractionations of a parental andesitic magma, accompanying a little contamination from the crustal assimilations near the chamber roof and wall. But chemically and isotopically distinct late intusions might have resulted from emplacement of any different magma batch.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3A
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• pp.341-347
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• 2008

Among coating systems used for steel bridge coatings on highway such as red lead-pigmented alkyd, chlorinated rubber, waterborne inorganic zinc, inorganic zinc/epoxy/urethane and inorganic zinc/epoxy/fluororesin, evaluation of deterioration degree and prediction of lifetime through regression analysis were carried out for coating systems widely used and grossly degraded. For evaluation of deterioration degree, 75 bridges on highway were selected, and evaluations were carried out according to point offering method regulated by Guideline of maintenance coating for steel bridges used in Korea Expressway Corporation. Lifetime prediction results showed 13.0~13.3 years for the whole nation, 11.8 years for urban and industrial region in the metropolitan area, 13.2 years for rural region except the metropolitan area, 13.5~13.7 years for chlorinated rubber coating systems, and 12.86 years for red lead-pigmented alkyd systems. For prediction of the rest life of coating, we tried to execute parallel translations of standard deterioration curve to current life and deterioration degree for both x and y axes, and it was thought that parallel translation for x axis corresponded to deterioration aspects in actual environment. Maximum and minimum equations were derived from standard deterioration equation by adding and subtracting error values deduced in regression analysis to/from each coefficient in order to establish maintenance coating criteria for overall steel bridges on highway. Whole domain was divided into 8 parts in order to predict the rest life of coating and optimum time of maintenance coating, and maintenance coating criteria for each 8 domains were presented.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.2
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• pp.213-217
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• 1990

This study suggests a new type flow control logic valve which have grooves on the main poppet valve. The grooves connect oil supply port to pilot chamber and the oil passages made by the grooves are designed to vary in proportion to the displacement of the main poppet valve. From analytical formulations on the hydraulic circuit including the flow control valve, equations on the characteristics of the valve were obtained. In the experiment, the relationships between valve displacement and flow rate to the load side, and the variations of flow rate to the load side according to the variation of load pressure were investigated. From the experimental and numerical results, it was ascertained that the flow control valve designed in this study had excellent characteristics on proportional control and remote control.

• Ceramist
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• v.20 no.1
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• pp.103-118
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• 2017

1. 2014년도 우리나라 전체 폐기물 발생량은 146,607천 톤이며, 건설폐기물이 46.2%(67,644천 톤), 사업장 일반폐기물이 38.1%(55,914천 톤), 생활폐기물이 12.4%(18,219천 톤), 사업장 지정페기물이 3.3%(48,810천 톤)을 나타내고 있다. 2. 건설폐기물의 97.9%, 배출시설계 폐기물의 77.3%, 생활폐기물의 67.0%, 지정폐기물의 57.3%가 재활용되고 있다. 3. 2015년도 우리나라 시멘트산업에서 18,801천 톤의 순환자원을 재활용하였다. 폐기물이 6,136천 톤이고, 부산물이 12,665천 톤이다. 부산물은 11,000천톤이 제철슬래그이고, 1,600천 톤이 폐석고(탈황석고 중화석고)로 추정된다. 그리고 폐기물 6,136천 톤은 사업장 일반폐기물의 약 11.0%에 해당된다. 4. 시멘트 톤당 순환자원 사용량(재활용 원단위)은 일본이 400kg/톤 이상이고 우리나라는 300kg/톤 대를 나타내고 있다. 일본이 우리나라보다 재활용량/톤이 많은 이유를 다음에서 찾을 수 있다. (1) 고품위 석회석 원료 (2) 법 제도(지원금 포함) 5. 원료 대체율의 산출은 다음 두 산출방법으로 나타낼수 있다. (1) 이론적인 원료 상한 대체량에 대한 실제 원료 대체량 (2) 이론적인 원료 조합량에 대한 실제 원료 대체량 2015년도 우리날 전체 원료 대체량(17,770천 톤)은 (1)에 의한 대체율 : 71% (2)에 의한 대체율 : 27% 6. 자동차 슈레더 더스트(ASR)를 시멘트산업에서 자원화 하게끔 ASR처리의 보완 및 법적지원(지원금 포함)이 요망된다. 7. 부산물 및 폐기물의 자원화는 시멘트산업에서의 이용이 가장 우수한 장점을 갖추고 있다. 그러므로 시멘트산업에서 폐기물의 자원화를 적극 추진하게끔 제도의 보완 및 시설지원 등 정부의 대책수립이 간절하다.