• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2A
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• pp.297-304
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• 2008

It is well known that cracks in concrete decrease permeability and durability of concrete because cracks enhance the penetration of water or corrosive chemicals like as chlorides, carbon dioxides, sulfates and some others. But some of cracks in hardened cements may be sealed in case of contacting water. This phenomenon is called "self healing" and it has a close relation to hydration products newly formed on surfaces of cracks. Many studies on self healing in concretes commonly showed that CSH gel has been observed on crack surfaces. And some studies have reported that calcium hydroxides and ettringite were observed as well as CSH gel on crack surfaces. This study was carried out to investigate hydration products formed by self healing process and also examine the influence of waterproof admixture for concretes on self healing of cement. As a result of XRD, DSC, SEM and EDX analysis of crack surfaces, it was found that self healing of cement was related to CSH gel, calcium hydroxides and ettringite. And waterproof admixture increased fibrous (needle-like) hydration products which were in network form. It is estimated that such fibrous products are effective for self healing process of cement system.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.246-246
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• 2004

본 연구는 발포유리 조성물 및 이를 이용한 발포유리 전구체의 제조방법에 관한 것으로, 구체적으로 알칼리 히드록시, 실리카 및 붕산으로 이루어진 발포유리 조성물 및 이를 이용한 발표유리 전구체의 제조방법에 관한 것이다. 본 연구에 의해 제조된 발포유리 전구체는 발포제의 사용없이 우수한 발포성능을 발휘하며, 특히 저온에서 발포성능을 나타내어 방열 및 방음용 유리 발포체로 사용할 수 있으며 각종 도료 및 페인트에 첨가하여 사용할 수 있다.(중략)

• Proceedings of the Korean Society for Information Management Conference
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• 2005.08a
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• pp.125-132
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• 2005

본 연구는 공공기관에서 생산되는 기록물로서 가장 일반적이고 대표적인 공문서의 장기보존과 접근을 위한 상호운용성을 갖춘 보존 메타데이터 요소를 설정하는데 그 목적이 있다. 구체적으로는 기록물관리 표준인 ISO 15489에서 제안하는 메타데이터 요소와 우리나라의 메타데이터 요소의 비교분석을 통해 전자문서관리시스템의 최고 핵심인 공문서의 보존 메타데이터 항목을 연구하였다. 이는 향후 우리나라 환경에 적합한 표준화된 기록물 보존 메타데이터를 구축하는데 유용한 기초 자료로 활용할 수 있을 것이다.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2015.11a
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• pp.168-169
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• 2015

최근 위험물질에 의한 폭발 및 테러의 위험성 증가로 인하여 사회간접자본 시설물인 댐/보, 원자력 발전소, 병원 구조물과 같은 주요 시설물의 폭발 안전성 평가 연구가 이슈화 되고 있어, 본 연구에서는 가스폭발에 의한 다기능 보 구조물의 거동을 평가하고 안전성을 분석 하고 자 한다. 본 연구에서 폭발 해석에 필요한 하중 조건 산정은 PHAST 프로그램을 사용하여 주변 온도 및 공기 특성 등을 고려한 약 5톤의 가스 폭발 조건을 구축 하였다. 또한 다기능 보 구조물의 거동 분석을 위해 구조물-지반 상호 작용을 고려한 2차원 유한 요소 모델을 구축하여 폭발에 의한 구조물 거동을 평가 하였다. 다기능 보 구조물의 수치해석 결과 보 구체와 Stilling Basin구조물 사이의 연결부에 응력집중 현상이 발생하는 것으로 평가 되었다.

• Computational Structural Engineering
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• v.6 no.4
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• pp.10-13
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• 1993

본 고에서는 불확정적 Approach에 의한 구조물 거동파악의 일례를 소개한다. 이 예에서는 극치통계와 엔트로피 최대원리를 이용하여, 부동침하를 받은 쉘구조물의 응력을 추정하는 이론을 취급한다. 부동침하는 불확정적 특성을 비교적 많이 지니고 있으며, 특히 구조물을 지지하고 있는 지반의 경우는 그 물리적 정수와 침하특성이 확정론적으로는 취급이 곤란한 경우가 많다고 생각된다. 구체적으로 극치통계법에서는 부동침하를 기초 Ring의 원주방향으로의 Fourier 계수로 가정하여, 위상각과 침하의 2승평균치가 확정치로 주어졌을 때, 진폭 Spectrum을 불확정변수로 간주하여 추정하는 방법을 소개한다. 일단 진폭 Spectrum이 구해지면 응력은 간단히 구해지므로 여기서는 Spectrum에 관해서만 언급하기로 한다.

• Proceedings of the KGS Conference
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• 2003.05a
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• pp.211-214
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• 2003

지도는 기호, 주기, 색상, 경위선, 축척 등과 같은 여러 요소들을 사용하여 지도 사용자들에게 다양한 지리적 사상들(geographic features)의 존재와 그들의 상관관계를 전달하는 일종의 의사소통 수단이다(황철수, 2002). 주기(label)는 $\ulcorner$지역, 인공물, 자연물의 고유명칭 및 고유명이 없는 것의 종류 또는 상태 등을 표시하는 설명 및 표고와 등고선수치 등을 문자 또는 숫자로서 표기하는 것1)$\lrcorner$, 즉 지도에 나타나는 사상들에 대해 설명하기 위해 입력되는 문자열을 의미하는 것으로 지도의 여러 가지 요소들 중에서도 가장 직접적이고 구체적으로 사상을 표현할 수 있는 요소이다. (중략)

• The Korean Society of Law and Medicine
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• v.17 no.2
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• pp.3-28
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• 2016

While product liability has been settled as a technical term in civil law, criminal law does not commonly accept technical term for it. Not like civil law, product liability in criminal law point outs individual responsibility and disability of normative order. Meaning that causation between individual's action of violation of duty and the result of danger of legal interest or infringement of legal interest must be proved. In criminal law excluding "non-result-constituted crimes (Unternehmensdelikt)", charge of injuring, accidental infliction of injury, homicide or involuntary manslaughter is problematic in product liability. Of course, it is necessary to distinguish whether the action related to the outcome is act or ommission. Also the causal relationship between the action and the result must be proved, and the intention or negligence should be recognized. In this paper, it analyzes cases that were problematic in Korea, Germany, Spain, etc. Mainly focusing on the problems revealed in the determination of causal relationship, especially recognizing criminal liability related to products. Furthermore it is followed by the view of reviewing the cause-and-effect relationship by 2 steps, dividing natural scientific causation and the normative causal relationship. In this process, to acknowledge criminal product liability in accordance with recognizing cause-and-effect relationship, there should be general risk of specific substance causing the outcome. This only premise can be meaningful to examine the casual relationship from specific cases. As it shows in some cases and theories, it is not contradicting general law of cause and effect by determining specific causal relationship by free evaluation of evidence if a general causal relationship does not exist. Also since judge's testimony does not hold a dominant position from rule of thumb, it is possible to recognize specific causal relationship. However this paper takes position that if there is no objective and reasonably undeniable cause and effect law. If there is no objective and reasonably undeniable causal law, which is the premise for recognizing concrete causal relations, judge should sentence guilty according to "in dubio pro reo" principle. In addition, it is not allowed for the defendant to burden unproven fact by free evaluation of evidence which has an effect of shift of burden of proof.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.1
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• pp.29-36
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• 2014

Dendrobium candidum is one of the well-known orchid on traditional and rare medicinal herb in China. We artificially cultured protocorm-like body and multiple shoots using the bioreactor culture system from Dendrobium candidum and experimented an efficacy as a cosmetic ingredient for skin care. Several studies previously have reported anti-tumor, wound healing and immunological function of Dendrobium candidum but other efficacies were not well known. In the present study, we investigated the cosmetic efficacy to know applicable value of protocorm-like body and multiple shoots cultured from Dendrobium candidum as a cosmetic ingredient. The biological activities of extracts from protocorm-like body, multiple shoots, aerial part and underground part of Dendrobium candidum were investigated. Results were found that extracts of protocorm-like body are superior to other extracts (underground part, aerial part and multiple shoots extracts) on anti-oxidant effect. Also, protocorm-like body extract contained the phenolic and flavonoid compounds more than aerial part, underground part and multiple shoots extracts. In addition, we investigated skin whitening effect related to whitening of skin. In tyrosinase activity and melanin synthesis assay, multiple shoots extract is superior to other extracts (aerial part, underground part and protocorm-like body), on inhibitory effect of tyrosinase activity and melanin synthesis respectively. These results indicate that the protocorm-like body and multiple shoots extracts cultured from Dendrobium candidum presents a new possibility of being applicable to skin improvement as a cosmetic ingredient.

• Journal of The Korean Association of Information Education
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• v.24 no.1
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• pp.11-19
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• 2020

Software education is provided for 6th grade students. This study explored the algorithmic composition patterns of elementary school students. After investigating the algorithm for the 6th grade students, the algorithmic pattern of the learner was explored by calculating the cyclomatic complexity of MacCabe based on the structural programming technique. Students often use one or two choice structures to solve problems, which tend to be biased towards the starting and ending points of the problem. It is also passive in the use of selection structures. Algorithm composition depends on visible objects and one's own background. Therefore, in elementary school software education, it is necessary to present the task of thinking about the algorithm structure in the context of the algorithm and the students' experiences in accordance with the algorithm composition pattern.

• Korean Journal of Heritage: History & Science
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• v.56 no.3
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• pp.254-273
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• 2023

In 2023, the Cultural Heritage Administration of Korea is transforming a system that has been in existence for the past 60 years. In these circumstances, an increasing recognition of the need for such changes is intended to start the study of the historical context in the conceptual development of cultural heritage. The employment of imported concepts of heritage created the demand for understanding at least the original contexts. Many European concepts have been introduced. In this study, the French Revolution is selected as the starting point for historical research on conceptual development. France opened a new horizon to national heritage since the establishment of the Republic at the end of the 18th century. The French Revolution placed monuments denied by the collapse of the Ancien Regime back into the boundaries of protection. In this process, the Commission des Monuments and the Commission Temporaire des Arts were created. There were limits to conservation activities in the context of the revolution and war. However, it is meaningful in that they established conservation principles with instructions and created new value for looking at monuments. It was pioneering in that it demonstrated the perspective of national heritage. This is significant because the top flow of conceptual development has led to a monument historique, bien culturel, and patrimoine culturel in France. This history provides a universal essence and has great implications for Korea as a divided country