• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.376-377
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• 1999

전세계의 많은 대도시들은 인구의 과밀화, 차량의 증가로 인한 교통혼잡 등으로 인해 많은 어려움을 겪고 있으며, 우리 나라도 '교통대란'이라고 할만큼 심각한 상황에 처해 있다. 이에 따라 1974년 1호선 9개역을 시발로 전국적으로 약 1,000km에 달하는 지하전철구간이 운행 건설 중이다. 지하철에 의한 수송 분담율도 꾸준히 증가하여 현재 서울에서의 경우 34％정도에 이르고 있으며, 2000년 이후에는 45％이상을 차지할 것으로 예상하고 있다.(중략)

• The Science & Technology
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• no.8 s.411
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• pp.8-11
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• 2003

인류 7만년 전 멸종위기 경험/ HIV 조상은 2種의 원숭이 바이러스/ HIV 저항력 항체 수수께끼 풀려/ 3억 8천만년 전 유성충돌로 어류 멸종/ 농약, 정자 수와 질 떨어뜨려/ 남성 Y염색체, 유전결함 스스로 치유/ "낮잠 자면 학습능력 향상"/ 원숭이도 소리와 표정 연결 능력 있다/ 전세계 어디라도 2시간내 폭격 극초음속 무인폭격기 개발한다/ 섹스 억제해도 정자 질 좋아지지 않아/ 새 소립자 '펜타쿼크' 발견/ 담배 못 끊는 건 유전자 탓(?)/ 비닐 쓰레기 먹는 박테리아 발견/ '쌍둥이 태양계' 발견

• Air Cleaning Technology
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• v.18 no.1 s.68
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• pp.53-78
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• 2005

Construction work is an art of making something out of nothing. To run the construction project smoothly, budget, organization and engineering should be balanced. Standardization and simplification of construction bill are needed in order to maximize the

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.298-301
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• 2003

한국지질자원연구원 내를 중심으로 유성일대에 분포하는 화강암은 대전지역을 관입한 화강암체의 일부로서 대부분 백운모를 함유한 복운모화강암으로 구성된다. 이 화강암은 주변에 분포하는 편상 화강섬록암이나 흑운모화강암에 비해 옥천층군의 잔류물을 거의 함유하지 않으며 암맥상의 폐그마타이트가 관입된다. 이 화강암은 중리질 내지 세립질이며 백운모가 흑운모보다 더 우세하거나 비슷하게 산축되는 등 다른 암석류에 비해 백운모를 다량 함유하는 것이 특징이다. (중략)

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.3
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• pp.153-161
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• 2023

The worldwide effects of COVID-19 have led to a surge in online shopping and contactless services. The consumption pattern has caused the issues such as the environmental pollution together with the increase of plastic waste. Reducing the reliance on the petroleum based plastic use for the package and replacing it with environmentally friendly material are the simple ways in order to solve those problems. Paper is an eco-friendly product with high recyclability as the food packaging materials but has still poor barrier properties. A barrier coating on surface of the paper can be achieved with the proper packaging materials featuring water, gas and grease barrier. Polyethylene (PE) or polypropylene (PP) coatings which are generally laminated or coated to paper are widely used in food packaging applications to protect products from moisture and provide water or grease resistance. However, recycling of packaging containing PE or PP matrix is limited and costly because those films are difficult to degrade in the environment. This study investigated the recyclability of modified acrylic emulsion coating papers compared to PE and PP polymer matrixes as well as their mechanical and gas barrier properties. The results showed that PE or modified acrylic emulsion coated papers had better mechanical properties compared to the uncoated paper as a control. PE or PP coating papers showed strong oil resistance property, achieving a kit rating of 12. Those papers also had a significantly higher percentage of screen reject during the recycling process than modified acrylic coated paper which had a screen rejection rate of 6.25%. In addition an uncoated paper had similar value of a screen rejection rate. It may suggest that modified acrylic emulsion coating paper can be more easily recycled than PE or PP coating papers. The overall results of the study found that modified acrylic emulsion coating paper would be a viable alternative to suggest a possible solution to an environmental problem as well as enhancing the weak mechanical and poor gas barrier properties of the paper against moisture.

• Economic and Environmental Geology
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• v.39 no.5 s.180
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• pp.537-554
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• 2006

Water levels of thermal groundwater ($>30^{\circ}C$) were recorded from March 2002 to June 2006 at several monitoring wells within the Yuseong spa area. Using these data, we elucidated the long-term cyclic fluctuations of thermal groundwater levels with 1 year period. We also observed a noticeable water level variation with periods of 0.5, 1 and 7 days in most monitoring wells, which indicates relatively good hydraulic connectivity within the main hotspring area. By comparing water level variations among several wells, we found out that E-W and N-S trending geological structures should be an important control factor for emplacement and flow of thermal groundwater in the study area. It may be also inferred that geothermal source is highly associated with the hydraulic connectivity of aquifers at the Yuseong spa area.

• Elastomers and Composites
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• v.38 no.4
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• pp.342-353
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• 2003

This work is about the development of jet-fuel resistant PVC sealant using a polyester plasticizer. PVC copolymer was compounded with adipic acid glycol(Songcizer P-3000) or DOP plasticizers. Fuel-immersed and non-immersed penetration, solubility, flow, and elongation by tensile adhesion of PVC compounds were measured. Penetration increase by fuel immersion and solubility of PVC compounds with adipic acid glycol polyester plasticizer were smaller than those of PVC compounds with DOP plasticizer. Elongation by tensile adhesion test of PVC compound containing 500 phr of Songcizer P-3000 decreased proportionally to the content of DCDP (dicyclopentadiene) base petroleum resin adhesion promoter. Calcium carbonate($CaCO_3$) filler inhibited the diffusion of fuel in all the PVC compounds and decreased the solubility of PVC compounds containing Songcizer P-3000.

• Industry Promotion Research
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• v.9 no.2
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• pp.45-58
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• 2024

This study modelled the social network structure characteristics between Innopolis Start-ups located in Daejeon and Innopolis Start-ups' customers scattered across the country as a tendency of regional clustering among homogeneous technologies, and the observed values were included within the 95% confidence interval of the ERGM(Exponential Random Graph Model) analysis model. If both the research institute and the customer company are located in Yuseong-gu, Daejeon, the probability of being connected is about 13 times higher than if they are located in other administrative districts, and there is a strong tendency of connection between firms with the same technology with a negative value of assortment and homogeneity (0.1904), especially among the six technology sectors, with a P value of 0.035. There was a negative value (-0.0035) among firms not located in Yuseong-gu, with less clustering tendency. This confirms that Yuseong-gu, Daejeon, where the Daedeok Innopolis is located, is forming the centre of an innovation cluster.

• Proceedings of the KSPS conference
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• 1994.02a
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• pp.45-53
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• 1994

음 변화 규칙을 음성규칙(A)와 음운규칙(B)와 기타(C)로 분류한다면, A.음성규칙의 발생 총계는 B.음운규칙의 발생 총계보다 2배 이상 더 많다. 여기에 가장 발생 빈도가 높은 규칙부터 순서대로 10개만 정리하면 다음과 같다. 순위 규칙부류 명칭 백분율 1 A 음절 말 유성자음의 불파화 31.84, 2 A 유성음화 19.37 3 B 장모음화 10.00, 4 A 설측음화 9.78, 5 B 경음화 6.43, 6 B 음절말 장애음 중화 5.16, 7 A ㅅ 구개음화 3.71, 8 C 음절 조정 규칙 3.10, 9 B 단모음화 1.60, 10 A ㄴ 구개음화 1.42 별도로 진행한 총체적 연구(이상억에 의하면, 음성규칙, 즉 A가 총 6개 있는데 그 중 5규칙이 10위 내에 나타나 상위 쪽에 3번이나 포함되어 있는 점이 주목된다. 특히 규칙 1과 2의 합계는 전체 중 51.2%를 넘는다. 규칙 10위까지의 합계는 전체 중 92.4%를 차지한다. 13.장모음화(10%)는 12.단모음화(1.6%)보다 훨씬 높은 출현빈도를 보인다. 또 각종 구개음화 규칙의 순위는 ㅅ(7위), ㄴ(10위), ㄹ(17위), ㄷ(26위) 구개음화로 분포되어 있음이 밝혀졌다. 한편 삭제규칙(음운탈락 및 단순화) 계열이 14, 15, 19, 21, 25, 28위에 널리 나열되어 있는 데 반해, 삽입규칙은 23위에 ㄴ삽입 하나가 보일 뿐이다.

• The Journal of Engineering Geology
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• v.4 no.2
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• pp.219-229
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• 1994

Since groundwater flow in fractured rocks is controlled by the distribution of fractures irregu1arly developed in space, it is not possible to understand the hydraulic characteristics of fractured aquifers using Theis equation which is applicable only to homogeneous isotropic confined aquifer. This study deals with the theoretical background of the fractal groundwater flow model with leakage, the methodology of calculation of the hydraulic parameters, and the application of the developed model to field data. From the result of the application of the fractal model to two field data in Hongcheon and Yusung areas, we obtained a good match between theoretical curves and observed curves, with the same hydraulic parameters at the pumping well and the observation well. In the two pumping test analyses, we have determined 1.9 of the fractal dimension. This means that the dimension of groundwater flow at these two sites is slightly smaller than radial flow.