• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.570-571
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• 2019

우리나라의 건설연장에서 발생하는 재해율은 OECD 국가 중 최고 수준이며, 건설현장에서 발생하는 다양한 재해에 대한 예비연구가 필요하며, 건설현장의 다양한 사고유형 중 무너짐(붕괴/도괴)이 38.5%로 가장 높게 나타나고 있으므로 사고원인에 대한 분석과 무너짐에 대한 사전 조짐을 판단할 수 있는 데이터 분석을 통한 예비연구가 필요하다고 할 수 있다. 본 논문에서는 건설현장은 현장의 특성상 사고가 발생하면 큰 사고로 이어지고, 2차사고까지 동반할 수 있기 때문에 건설현장의 상태정보를 체계적으로 관리할 수 있는 안전사고 예방/관리 플랫폼 및 상태계측모듈을 연구개발하며, 건설현장 상태정보로부터 안전사고가 발생할 수 있는 조건을 예측할 수 있는 분석 알고리즘 개발에 대한 연구를 수행하고자 한다.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.5
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• pp.38-48
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• 2004

Recently the use of high-speed equipment in machine-tool industry has greatly increased, which requires the development of prognostics and prediction methods on the design stage. Conversion of the test/experiments stage from real to virtual reality will not only significantly reduce the design and manufacturing cost, but will also increase design quality. This paper shows how it is possible to develop the automated system for the design calculations of the air-bearing spindles. First, the general calculation method is introduced. It contains several steps, namely, geometry identification, pressure calculation, stiffiness calculation, dynamics characteristics calculation. For geometry identification reducing spindle shaft to rings was proposed, which helps to automate the calculation process. For pressure calculation the Peshti method was implemented. For stiffiness calculation the analysis was made, which shown the necessity of correct calculation step selection. Then the system of ordinary differential equations containing influence coefficients was evolved, which is used for trjectories calculation. The graphical representation of the calculation results shows the dynamic behavior of the spindle unit concerning various working conditions. Finally, this automated system is illustrated by an example of the air-bearing spindle calculation.

• The Journal of Engineering Geology
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• v.11 no.1
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• pp.13-23
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• 2001

Rock slope near the road or railroad is affected by the outside temperature and iterative freezing-thawing process during winter and early spring. The purpose of this study is to analyze the stability of rock slope which is iniluenced by deterioration due to the freezing-thawing. Method of analysis is homogenization method which find the strength property of discontinuous rock mass and as a strength failure criterion, Drucker-Prager failure criterion is used, The deterioration property of real rock is obtained by a freezing-thawing labordtory test of tuff and this quantitative property is used as a basic data of stability analysis of rock mass. To evaluate the deterioration depth due to the freezing-thawing in the field rock slope, one dimensional heat conductivity equation is used and as a a result we can find the depth of which is affected by a temperature. After determined the freezing-thawing depth of model slope, the pattern of rock mass strength value of model rock slope which excess the limit of self-load is analyzed.

• Journal of the Korean Society for Precision Engineering
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• v.4 no.2
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• pp.17-19
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• 1987

지난해 우리나라 경제는 안정속에 고도성장과 국제수지 흑자를 기록한 값진 보람을 느낀 한 해였다. 그러나 이같은 흑자기조는 개개기업의 성장잠재력에서 찾아볼 수도 있겠으나 대부분이 3저요인을 배경으로한 수출환경의 변화에 힘입은 바 크다. 그럼으로 언제 무산될지 모르는 장래를 낙관만 할 수는 없다. 지금의 현상을 어떻게 보는가에 대하여는 각계각층이 보는 시각에 따라 견해가 달라지겠으나 분명한 것은 국제유가나 국제이자가 오름세를 보이기 시작했다는 사실과 우리에게 국제경상수지흑자시대를 열어준 3저호재는 확실히 변해가고 있다는 것이다. 이렇게 볼 때 우리나라 경제는 해외요인변화에 매우 예민함으로 지금, 흑자기조가 정착되었다고 속단하기에는 너무 이른것 같다. 적어도 흑자기조가 정착되려면 모든 산업간, 계층간, 지역간의 불균형이 시정되고 기존의 산업기반을 내실화하는 단계에 있을 때 비로서 흑자경제의 향배가 가름하게 되는 것이다. 최근에 일어나고 있는 원화의 지속적인 평가절하, 엔화강세에 따른 원자재가격폭등은 우리에게 적지않은 위협을 주고있다. 이같은 상황에서 정부는 올해 국제수지흑자의 적정선유지를 위해 대미구매사절단의 파견, 수입선의 다변화, 수출지원정책의 감소등 다각적인 정책을 선택하고 있는 것으로써 일응 올바른 판단으로 수긍하나 다만 업종에 따른 특성에 배려가 있었으면 한다. 특히 우리나라의 기계공업은 20년의 짧은 근대화건설 과정에서 그나마 지금의 수준과 규모의 기반을 닦아왔다. 그러나 아직도 기술면에서 많은 취약점을 지니고 있어 대부분의 기초소재와 핵심부품이 해외에서 수입되고 있는 실정이다. 따라서 기계공업이 명실공히 선도산업으로써 의 위치를 굳히기 위해서는 적어도 기계류의 수입국에서 수출국으로의 탈바꿈을 할 때 비로소 성취될 것이며, 이 때가 관련산업간의 불균형이 시정된 흑자시대라고 보는 것이 옳을 것 같다. 작금의 주변환경은 서두에서 언급한 3저호재에 심상치 않는 조짐이 보이고 있다. 이같은 주변환경에 관점을 두고 지금 우리가 당면하고 있는 과제 중의 하나인 원화절상을 지적하지 않을 수 없다. 이같은 원화절상내용을 중심으로 부가적으로 수반된 몇가지의 현안문제와 함께 점검해 보기로한다.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.14 no.1
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• pp.67-73
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• 2011

Purpose: Recently, the incidence of acute hepatitis A has increased nationwide and is related to a low rate of IgG anti-HAV production. To establish effective measures for preventing hepatitis A virus infection, an epidemiologic study on the seroprevalence of anti-HAV is needed. Thus, we investigated the seroprevalence of IgG anti-HAV in children living in Gwangju and Jeonnam. Methods: IgG anti-HAV levels were measured in a total of 1,435 patients who visited Chosun University Hospital between January 2009 and December 2009. Results: The overall seropositve rate was 40.8% (586/1,435). The seropositive rates were 41% among children under the age of 1 year, 49.9% for children 1~5 years old, 51.1% among individuals 5~10 years old, 12.9% for individuals 10~15 years old, and 8.2% for subjects over 15 years old. There was no significant difference between genders in any group. The seropositive rates in Gwangju and Jeonnam were 57.3% and 32.9% for children under the age of 1 year, 52.5% and 44.3% for children 1~5 years old, 60.2% and 33.9% among children 5~10 years old, 14.1% and 9.7% for children 10~15 years old, and 10.8% and 4.2% for individuals over 15 years old. Conclusion: The results demonstrated the low rates of IgG anti-HAV, particularly among subjects over 10 years old, which suggests the possibility of increasing clinical HAV infection rates among adults in the near future. We should actively prevent the spread of hepatitis A virus. Vaccination is the most effective means of preventing hepatitis A virus transmission among persons at risk for infection. Hepatitis A vaccination is recommended for children who have low IgG anti-HAV seropositive rates.

• Korean Journal of Heritage: History & Science
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• v.42 no.1
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• pp.100-121
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• 2009

This study is subjected to those gardens of the Korean Folk Village 'Oeam-Ri' designed in 1920s. - transitional period of traditional gardens - and define socio-cultural change's influences and through documents on garden design, descendant's testimony and measured drawings, to understand that period's garden culture's characteristics according to garden design elements. This study applied following analysis methods and procedures to derive out characteristics of transitional garden culture. Analysis on socio-cultural characteristics in 1920s. Analysis on actual condition of transitional garden's design. In this point Outline of the Garden, Space formation, Garden designing elements are (1) water landscape, (2) plant, (3) structures, (4) paving, to derive out characteristics of the transitional garden. The results follow as below; First, during the transitional period 1920s, the economical development, fueled by opening nation's door to foreign countries and indication of collapse of statue systems together with idea of practical science and Enlightenment Thought, was element of changes in garden style. Second, Garden Designers of transitional gardens in 'Oeam-Ri' were limited to upper class of the society. They were wealthy enough to maintain their high social statue in rapidly changing society. As results, tendency of returning to nature developed gardens located in a site of scenic beauty and development of geographical features arranging techniques, and also showed copying foreign styles. Third, arrangement of garden and space composition, in most cases, composed of buildings and yards. Changes in water landscape features and garden spaces are centered to main-yard. Major changes of the garden spaces are water landscapes and plants that showing foreign influences. Fifth, scenic appearance techniques appears with dense garden space and emphasizing visual scenic view. Sixth, the characteristics of transitional garden design techniques are development of geographical feature arranging techniques, changes and mixture of the materials and garden types, emphasizing garden's decorative beauty, change of concept of yard within house into garden, changes from 'borrowing of landscapes' to 'selecting landscapes', changes of front garden from emptiness to fullness, changes of attitudes of enjoying gardens from 'staying calm in the garden' to 'moving or walking in the garden', changes to inner-oriented view, and changes from 'just watching and enjoying the nature' to 'enjoying specific objects'. This study is one of the efforts to restore the identity of Korean Traditional Garden by approaching and observing modern era which function as bridge between tradition and present day, and we observed transitional aspects of changes of traditional garden into modern garden. Hereafter, more studies will be needed to Modern Garden Design be recognized as part of Korean Garden Design History and these would be author's next assignment.