• Title/Summary/Keyword: REA

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characteristic of Ions in Rainwater at Air Polluted and Non-POLLUTED aREA (대기오염지역과 비오염지역 강우의 이온특성)

  • ;Yositake, F.;Junichi, T.
    • The Korean Journal of Ecology
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    • v.21 no.3
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    • pp.195-201
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    • 1998
  • This study was carried out to investigate characteristic of ions in rainwater by throughfall, stemflow and rainfall at air polluted area(Kure city industrial city) and non-air polluted area (Higashihiroshima city non industrial city). pH of rainwater in air polluted area were all low as compared with those in non-air polluted area. EC of rainwater in ir polluted area were high in throughfall and stemflow, but there was no difference between both areas in rainfall. The concentration of major ions in rainwater were generally high at air polluted area, especially of $Mg^{2+}$, $Ca^{2+}$, $Cl^{-}$ and $SO_4^{2-}$ in stemflow. But there was little difference in $NH_4^{+}$, and there was also cases had a high concentration in non-air polluted area. By comparison with forest type, in stemflow concentration of ions in coniferous forest were higher than those in broad-leaved, but in throughfall they were higher in mixed forest rather than coniferous forest. There was no correlation between the amount of rainwater and pH, and also EC. $NO_4^{-}$ and $SO_{4}^{2-}$ had high correlations between major ions besides $Na^{+}$ and $NH_{4}^{+}$ in air poluted area.

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Effects of Materials Composition in CNT Paste on Field Emission Properties in Carbon Nanotube Cathodes (인쇄용 페이스트의 조성변화가 탄소나노튜브 캐소드의 전계방출 특성에 미치는 영향)

  • Choi, Woo-Suk;Shin, Heo-Young;Kim, Dong-Hee;Ahn, Byung-Gun;Chung, Won-Sub;Lee, Dong-Gu;Cho, Young-Rea
    • Korean Journal of Materials Research
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    • v.13 no.10
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    • pp.663-667
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    • 2003
  • The effects of paste materials on field emission properties in a carbon nanotube(CNT) cathode were investigated for high-efficient field emission displays. The major components in CNT paste for screen printing were a metallic Ag-paste, a dielectric glass-frit and CNT ink. The emission current from the cathode by an electron tunneling effect increased with an increase in the dielectric material fraction in the CNT paste, which is related to an increase of field enhancement factor in Fowler-Nordheim equation. The surface treatment used, after soft baking of the screen-printed CNT films, greatly affected the decrease in the turn-on field in CNT cathode and the uniformity of emission sites over the entire CNT film area.

A Study on the smartphone management standards(OMA DM) (스마트폰 관리 표준(OMA DM)에 관한 연구)

  • Bae, Jung-Min;Jung, Sung-Jae;Bae, Yu-Mi;Jang, Rea-Young;Soh, Woo-Young
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.253-255
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    • 2013
  • It is being exposed to hazard about the person or company's information, according to mobile-telecommunication's development. Those situations are being threatened to private information exposure and in a bid to stop the outflow of new technologies from coporations or goverment. to resolve this issue, the administration of SMART phone's applications and the skill of handling for device applying the standard of DM defining protocol and Mechanism Study into the software management and Device supervision under controlling, OMA which is affiliated to Mobile Service Standard Organization.

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The Cause of Jeong-Jo's Death Based on The Annals of the Chosun Dynasty (朝鮮王朝實錄), Seungjeongwon Ilgi (承政院日記) (정조의 사망원인에 대한 연구(조선왕조신록과 승전원일기를 중심으로))

  • Kim, Sun-Hyung;Kim, Dal-Rea
    • The Journal of Korean Medicine
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    • v.30 no.4
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    • pp.142-161
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    • 2009
  • Objectives: There are many unknowns surrounding Jeong-Jo's death. To better understand Jeong-Jo's death, we closely inspected his medical records from the 20 days before his death in The Annals of the Chosun Dynasty (朝鮮王朝實錄) and Seungjeongwon Ilgi (承政院日記), Understanding medical treatment before death, we can correctly trace the cause of Jeong-Jo's death. Methods: According to The Annals of the Chosun Dynasty (朝鮮王朝實錄) and Seungjeongwon Ilgi (承政院日記), we examined his medical records between June 14 and June 28 of 1800, as to the change in chief complaint, cold and heat, thirst, syndrome differentiation, the opinions of Jeong-Jo, and the opinions of doctors, The original work, The Annals of the Chosun Dynasty and Seungjeongwon Ilgi were provided by NIKH (The National Institute of Korean History). The Korean translation of The Annals of the Chosun Dynasty was also provided by NIKH. Seungjeongwon Ilgi (original work written in Chinese characters) was directly translated into Korean by the study author. Results: 1. Jeong-Jo's is likely to have died of septicemia caused by an abscess on his back. 2. The cause of Jeong-Jo's death could be stroke due to hypertension, mental stress, and 'Wha (火) disease' Conclusions: The dominant view that Jeong-Jo was murdered by poison is not likely.

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A Study on the Control Performance for Hazardous Gases by Surface Discharge induced Plasma Chemical Process (연면방전의 플라즈마 화학처리에 의한 유해가스제어 성능에 관한 연구)

  • 이주상;김신도;김광영;김종호
    • Journal of Korean Society for Atmospheric Environment
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    • v.11 no.2
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    • pp.185-190
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    • 1995
  • Recently, because of the worse of the air pollution, the excessive airtught of building and the inferiority of air conditioning system, the development of high efficiency air purification technology was enlarged to the environmental improvement of an indoor or a harmful working condition. The air purification technology has used chemical filters or charcoal filters or charcoal to remove hazardouse gaseous pollutants (SO$_{x}$, NO$_{x}$, NH$_{3}$, etc.) by air pollutant control technology, but they have many problems of high pressure loss, short life, wide space possession, and treatment of secondary wastes. For these reason, the object of reasearch shall be hazardous gaseous pollutants removal by the surface discharge induced plasma chemical process that is A.C. discharge of multistreams applied A.C. voltage and frequency between plane induced eletrode and line discharge eletrode of tungsten, platinum or titanium with a high purified alumina sheet having a film-like plane. As a result, the control performance for hazardous gaseous pollutants showed very high efficiency in the normal temperature and pressure. Also, after comtact oxidation decomposition of harmful gaseous pollutants, the remainded ozone concentration was found much lower than that of ACGIH or air pollution criteria in Korea.rea.

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Stabilization of Tyrosinase for Catechol Production (Catechol생산을 위한 Tyrosinase의 안정화)

  • 박종현;김용환유영제이윤식
    • KSBB Journal
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    • v.9 no.5
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    • pp.525-531
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    • 1994
  • Tyrosinase has two types of enzymatic activities, cresolase catalyzing the hydroxylation of monophenol and catecholase catalyzing the oxidation of o-phenol. Gradual inactivation of the enzyme during the reaction is a barrier to be overcome for the commercial application of the enzyme. Tyrosinase was stabilized by modifying the lysine residue of the enzyme using glutaraldehyde. In addition to that, tyrosinase was also stabilized by adapting the continuous reactor system. In packed bed reactor quinone could be easily removed, so the stability of tyrosinase increased. Borate buffer retarded the reaction rate of catechol to quinone and consequently decreased the tyroslnase inactivation. Tyrosinase immobilizer on controlled pore glass showed significantly enhanced stability in a packed-bed reactor.

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A Case Study on Overseas Policy for Effective Conservation of Natural Resources (자연자원의 효율적인 보전을 위한 해외정책 사례 연구)

  • Yoon, Ho-Jung;Yeom, Sung-Jin
    • Journal of Environmental Science International
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    • v.29 no.11
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    • pp.1033-1054
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    • 2020
  • Repeated use of land is depleting future resources and causing many ecological problems, prompting the need for a natural resource policy focusing on effective conservation. This study aims to identify methods based on international cases useful for introducing sustainable conservation of domestic natural resources. Currently, South Korea has developed and enforced many management and evaluation strategies for natural resources. However, due to limitations on policies and management, they show signs of strain. Therefore, this study compares and analyzes international conservation policies for nature and scenery, such as Germany's impact mitigation regulation, the USA's HEA (habitat equivalency analysis) and REA (resource equivalency analysis) policies, and Japan's three laws for landscape and greenery, to achieve the following three goals: first, find natural resources suitable for South Korea and define them. Second, plan goals for mitigation of total natural resources and build a basis for them. Third, establish effective complete plans for evaluating the total amount of natural resources.

A study on the effectiveness of the mathmatically gifted program (초등학교 영재를 위한 수학 프로그램의 실효성에 관한 연구 - Parallel Curriculum Model을 중심으로 -)

  • Whang, Woo-Hyung;Yoon, Na-Rea
    • Communications of Mathematical Education
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    • v.23 no.1
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    • pp.53-72
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    • 2009
  • The purpose of the study was to develop a program based on PCM(Parallel Curriculum Model) model for the gifted students, and investigate the effectiveness of the program with qualitative research methods. This program was designed to encourage the gifted students to explore mathematics that is closely related to the real world. The results of the study revealed that the program based on the PCM model had positive effect on the gifted students emotionally and cognitively. In conclusion, PCM program is considered an appropriate program for the gifted students of elementary school.

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Finite Element Analysis of Re-Cold Expansion in Order to Improve the Fatigue Life of Fastener Hole that has been Cold Expanded Before (홀확장법을 적용한 체결홀의 피로수명 개선을 위한 재 홀확장 효과에 대한 유한요소 해석)

  • Jang, Jae-Soon;Yang, Won-Ho;Cho, Myoung-Rea
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.9 s.252
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    • pp.1110-1115
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    • 2006
  • Cold expansion of fastener holes has been successfully used for many years to impart beneficial compressive residual stresses. Beneficial compressive residual stress of fastener hole that has been cold expanded before is reduced by using of materials for a long time. As a result, fatigue life of material is reduced. So, compressive residual stresses of material have to regenerate by re-cold expansion method. In this paper, it was carried out a finite element analysis about variation of residual stress due to tensile stress and residual stress distribution that was regenerated by re-cold expansion method in the fastener hole. Here, a diversity tensile stress was used. Also, it was performed a finite element analysis according to cold expansion rate of re cold expansion in order to obtain a beneficial compressive residual stress.