• Journal of the Mineralogical Society of Korea
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• v.26 no.3
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• pp.209-218
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• 2013

This study was to characterize the minerals in fractured and bedrock zone, and determine quantitatively sorption for radioactive cesium ($^{137}Cs$) at the Korean nuclear facility site. The rock samples were granite group that mainly consists of quartz and feldspar with 10~20% mica minerals. Chlorite was observed as secondary mineral for the rock samples collected from fractured zone, but not for bedrock samples. The $^{137}Cs$ sorption distribution coefficients increased to $K_d$ = 880~960 mL/g in the fractured zone because of the presence of secondary minerals formed by weathering processes, compared to the bedrock zone ($K_d$ = 820~840 mL/g). These results suggest that the released $^{137}Cs$ to groundwater environment could be significantly retarded in the fractured zone in the case of severe nuclear accident at the study site.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.266-267
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• 2011

질화갈륨(GaN)은 높은 전자이동도 및 높은 항복전계를 가지며 낮은 온저항으로 인하여 에너지효율이 우수하기 때문에 고출력 전력소자 분야에서 많은 관심을 받고 있다. GaN을 이용한 고출력 전력소자의 경우 상용화 수준에 근접할 만한 기술적 진보가 있었으나, 페르미 레벨 고정(Fermi-level pinning) 현상, 소자의 누설전류 등 아직 해결되어야 할 문제를 갖고 있다. 본 연구에서는 실리콘 기판 위에 성장된 GaN 에피탁시를 활용한 고출력 전력소자의 누설전류를 억제시키기 위해 오믹 접합 중 Au의 상호확산을 억제하는 중간층 금속(Mo or Ni)을 변화시켰으며 오믹 열처리 온도에 따른 특성을 비교 연구하였다. $Cl_2$와 $BCl_3$를 이용하여 0.6 ${\mu}m$ 깊이의 메사 구조가 활성영역을 형성하였고, Si 도핑된 n-GaN 위에 Ti/Al/Mo/Au (20/100/25/200 nm) 와 Ti/Al/Ni/Au (20/100/25/200 nm) 오믹 접합을 각각 설계, 제작하였다. 오믹 열처리시의 GaN 표면오염을 방지하기 위해 $SiO_2$ 희생층을 증착하였다. 오믹 접합 형성을 위해 각 750$^{\circ}C$, 800$^{\circ}C$, 850$^{\circ}C$에서 30초간 열처리를 진행 하였으며, 이후 6 : 1 BOE 용액으로 $SiO_2$ 희생층을 제거하였다. 750, 800, 850$^{\circ}C$에서 Ti/Al/Mo/Au 구조의 오믹 접합 저항은 각 2.56, 2.34, 2.22 ${\Omega}$-mm 이었으며, Ti/Al/Ni/Au 구조의 오믹 접합 저항은 각 43.72, 2.64, 1.86 ${\Omega}$-mm이었다. Isolation 누설전류를 측정하기 위해서 두 개의 오믹 접합 사이에 메사 구조가 있는 테스트 구조를 제안하였다. Isolation 누설전류는 Ti/Al/Mo/Au 구조에서 두 오믹 접합 사이의 거리가 25 ${\mu}m$이고 100 V일 때 750, 800, 850 $^{\circ}C$의 열처리 온도에서 각 1.25 nA/${\mu}m$, 2.48 nA/${\mu}m$, 8.76 nA/${\mu}m$이었으며, Ti/Al/Ni/Au 구조에서는 각 1.58 nA/${\mu}m$, 2.13 nA/${\mu}m$, 96.36 nA/${\mu}m$이었다. 열처리 온도가 증가하며 오믹 접합 저항은 감소하였으나 isolation 누설전류는 증가하였다. 750$^{\circ}C$ 열처리에서 오믹 접합 저항은Ti/Al/Mo/Au 구조가 Ti/Al/Ni/Au 구조보다 약 17배 우수하였고, 850$^{\circ}C$ 고온의 열처리 경우 Ti/Al/Mo/Au 구조의 isolation 누설전류는 8.76 nA/${\mu}m$로 Ti/Al/Ni/Au의 누설전류 96.36 nA/${\mu}m$보다 약 11배 우수하였다. Ti/Al/Mo/Au가 Ti/Al/Ni/Au 보다 오믹 접합 저항과 isolation 누설전류 측면에서 전력용 GaN 소자에 적합함을 확인하였다.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.1
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• pp.1-8
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• 2017

Drinking water deficiency is prevalent in developing countries due to contamination of surface and ground water, difficulties of water treatment, and lack of water infrastructures. 'Rainwater For Drinking (RFD)' projects are emerging as one of the effective solutions globally since RFD systems provide safe drinking water from rainwater. In RFD projects, perception of local residents toward RFD project is essential as local residents must manage their RFD systems on their own after the project finishes. This research performed survey and interview to 209 local residents, who use RFD systems, and analyzed their general perception, expected effects and feared factors toward RFD projects. Through the research, it was shown that the most of the local residents have positive perception towards RFD projects' effectiveness (41.9%) and are willing to participate (58.9%). The top three expected effect factors of the RFD projects were 'supply of safe water source', 'vitalization of local community', and 'expansion of RFD system'. The top three feared factors were 'quality of rainwater', 'technical factors of RFD system', and 'maintenance of RFD system'. The research findings indicate that development of simple water quality measuring device and education of the local residents about RFD system is necessary for better maintenance of the RFD system after the project finishes.

• Korean Business Review
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• v.14
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• pp.77-93
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• 2001

The ISO issued the first standard for environmental management standard(EMS) in 1993. This standard provide for elements of an effective environmental management system and can also help companies ingrain effective environmental management practice into their overall business operations. ISO 14001 is predicted to become the leading voluntary environmental management system standard. Companies selling products and services internationally and domestically will also be affected by publication of this standard. Especially, this new environmental management standards are fast becoming a condition for doing global business because it can be acted with trade barriers. Actually, an automobile companies of America including Ford and GM require their subcontracting companies to gain the recognition of ISO 14001. The purpose of this paper is to investigate the ISO 14000 and its application of Korean firms focusing on environmental management system(EMS). This paper proceeds to present the effective alternatives through analysing the existing Korean firms which has established EMS. Korean firms should adopt EMS not for the enhancement of corporate image but for the purpose of strategic competitive advantage.

• Journal of Radiation Protection and Research
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• v.40 no.4
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• pp.244-251
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• 2015

The containment filtered venting system reduces the range of the contamination area around the nuclear power plant by strengthening the integrity of the containment building. In this study, the probabilistic assessment code MACCS2 was used to assess the effect of the CFVS to off-site. The accident source term was selected from a Probabilistic Safety Analysis report of SHINKORI 1&2 Nuclear Power Plant. The three source term categories from 19 STC were chosen to evaluate the effective dose and thyroid dose of residents around the power plant and the dose with CFVS and without CFVS were compared. The dose was calculated according to the distance from the nuclear power plant, so the damage scale based on the distance that exceeds the IAEA criteria for effective dose (100 mSv per 7 days) and thyroid dose (50 mSv per 7 days) were compared. The effective dose reduction rates of the STC-3, STC-4, STC-6 were about 95-99% in the whole range (0~35 km), 96-98% for the thyroid dose. There are similar results between effective dose and thyroid dose. After applying the CFVS, the damage scale that exceeds the effective dose criteria was about 1 km (mean). Especially, the STC-4 damage scale was decreased from 26 km (mean) to 1.2 km (mean) significantly. The damage scale that exceed the thyroid dose criteria was decreased to 2~3 km (mean). The STC-4 damage scale was also decreased significantly as compared to STC-3, STC-6 in terms of effective dose.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.295-303
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• 2006

To provide microbial information for the safety of agricultural production, the presence of enterotoxin genes and antibiotic susceptibility of 14 isolated Staphylococcus aureus (11.7%) strains were investigated using PCR-based methods and disk diffusion method, respectively. Among enterotoxin-encoding genes, sea was detected from two isolates (14.3%), sea and sed genes were co-detected from three isolates (21.4%), and sea, sed, and see genes in seven isolates (50.0%), whereas seb, sec, and tsst were not detected in any isolate. Nine (64.3%), eight (57.1%), six (42.9%), two (14.3%), and one (7.2%) isolates were resistant to penicillin, novobiocin, amphicillin, erythromycin and oxacillin, and doxycycline and kanamycin, respectively. Methicilline-resistant S. aureus was found in roller of B farm and in hydroponic solution of D farm.

• Convergence Security Journal
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• v.12 no.2
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• pp.99-106
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• 2012

March 11, 2010, in Japan located over East Sea of Korea, due to the strong earthquake tsunami, Fukushima Nuclear Power Plant was ceased and exploded resulting in leaking radioactive substances. Even though it was an accident happened in a nation, leaked radioactive substances were spread across the world moving along ocean currents and air current. Our nation also had terror and confusion about radioactive rain after the accident, and even though a year has been passed by after the accident, the problem on the radioactive contamination isn't solved. So to speak, nuclear accident of neighboring country is a threat to our nation but not only Japan but also Chinese ocean across the West Sea has nuclear power plants. Beside threat of nuclear accident of neighboring countries, North Korea in military confrontation is the world 3rd country holding chemical and biological weapons and can spray the biological weapons to South Korea at any time like Yeonpyeong-do bombard provocation in November, 2010. The study is the strategy confronting such threats and grafted artificial rain technology which is weather control technology. Since radioactive substances on radioactive accidents and North Korean biological weapons can differ in the density by the weather condition, only artificial rain technology can remove the threat perfectly but it is worth to try as the method to reduce damage and in the aspect of psychology. To use the artificial rain technology in the aspect of national security to acquire the public safety, research institutes such ADD should fulfill active and symbolic technology research development.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.6
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• pp.40-49
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• 2017

The purpose of the research is to analyze the recent cases of green space planning and planting design in Beijing, one of the cities having the worst particulate matters (PM) pollution. This study comprehensively reviewed Chinese academic literature addressing green space planning to reduce PM pollution. In addition, we conducted field observations and interviews with public officials from Beijing Municipal Bureau of Landscape Design in charge of planning and management of green spaces in Beijing. After the extensive review of literature we derived tree planting principles to mitigate the impact of PM from urban road system, residential area, and industrial district. Using the principles we evaluated the three recent cases of planting design to mitigate PM: Beijing Fuxing Road, Fu Run Residential Area and Beijing Beiqi Multipurpose Vehicle Factory. We conclude that green space planning and trees planting are not effective in mitigating negative impact of PM pollution because of inadequate selection of trees and inconsiderate planting composition. We proposed to replace the tree species with the ones capable of reducing the spread of PM, and reorganize planting compositions that consider the directions and characteristics of urban wind flow. This study suggests desirable types of tree species and planting compositions for road, residential and industrial districts, and we expect that it provides helpful guidelines for making planting design and species selection to mitigate the impact of PM in urban landscape.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.597-603
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• 2012

To investigate the effects of weir construction on sediment characteristics of river bed, we conducted sediments sampling on the 9 locations near the weir, Kangchun, Yuju and Ipo in Namhan-River. Physical and chemical characteristics of sediments were analyzed by measuring particle size distribution, water content, Ignition loss, COD (Chemical Oxyzen Demand), TOC (Total Organic Carbon), TP (Total Phosphorus), SRP (Soluble Reactive Phosphorus) and TN (Total Nitrogen). Particle classification of all three weir sediments showed sandy loam that was caused by the river bed dredging. Due to the presence of weir, Ignition loss, COD, TOC, TP, SRP and TN showed similar trend such as the concentrations of upward weir had higher than those of downward weir. For the case of SRP concentration and C/N ratio, however, there is not much difference in the sediment characteristics compared to the those of sediments before weir construction. Therefore, It can be predicted that there are little effects of weir construction on sediment characteristics. However, weir construction could influence water quality of the river by controlling the transport and the accumulation of suspended materials from rainfall. Therefore, more intensive monitoring is required to examine the magnitude and patterns of sediment accumulation which could influence overlying water quality.

• Proceedings of the KAIS Fall Conference
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• 2004.06a
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• pp.324-326
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• 2004

20세기 말까지만 해도 경제발전은 자원고갈과 자연환경파괴를 통한 대량생산 및 대량소비를 전제로 하여 이루어 졌다고 평가할 수 있다. 그 결과 세계의 자연환경은 급속히 훼손되었으며, 환경오염은 이제 인류의 생존을 위협하는 단계에 이르렀다. 이 같은 위기상황에 대처하기 위하여 지난 1980년대부터 선진국을 중심으로 환경경영에 대한 인식이 확산되기 시작하였다. 무엇보다도 자연환경 의 보존을 요구하는 사회적 압력은 기업으로 하여금 환경경영 의 필요성을 깨닫게 하였다. 환경 경영이란 기업들이 새로운 비교 우위를 창출하기 위하여 경 영 방식의 혁신에 있어서 자연환경을 초점으로 삼는 것이다. 환경경영이란 환경보전을 요구하는 이해 관계자들로부터의 요구에 기업이 이에 적극적으로 대응함으로써 한경보호와 경영성과를 동시에 달성하는 종합적인 경영을 의미한다. 환경경영은 이업의 전 활동에 걸친 전사적인 전략적 차원의 활동으로 기업경영이 어느 한 기능분야에 국한된 개념이 아니다. 궁극적으로 환경보호와 성장의 조화라는 기업의 목표달성을 위해 기업의 생산, 재무, 인사조직, 마케팅, 회계정보시스템등의 활동이 모두 통합되어야 할 것이다. (김종대, 이의훈:2003) 최근 들어 환경경영이 기업의 가치에 미치는 영향에 대한 연구가 활발히 전개되고 있는 가운데 선진국의 경우 기업의 가치가 대체적으로 정확하게 주가에 반영되고 있는 가운데 선진국의 경우 기업의 가치가 대체적으로 정확하게 주가에 반영되고 있어 우리기업들이게 시사하는 바가 크다 하겠다. 환경경영과 기업가치와의 상관관계를 조사한 연구결과에 따르면 우수한 환경경영을 실천하고 있는 기업의 주식을 중심으로 포트폴리오를 구성한 펀드의 수익율이 상대적으로 높게 나타나고 있어 환경경영의 중요성을 뒷받침하고 있다. 이를 위하여 본 논문은 우선적으로 기업의 환경경영에 기본이 되는 중요한 환경경제 유인정 책과 규제들을 중심으로 살펴보고자 하였다.학적 합성이 아주 까다로운 약제물질 등을 천연상태에서 합성하고 있기 때문이다. 또 식물은 lipoxygenase 효소계가 있어서 마치 천연물 석유제조공장과 같은 제조공정 capacity를 가지고 있다. 그러면 식물/식품 GMO는 안전한 것인가? 아니, KBS의 한 사회자가 말했듯이, 그리고 많은 소비자들이 믿는 것처럼 GMO는 위험한가? GMO에 대한 일반 사람들의 공포감은 Green Peace 당원들뿐만 아니라 일부 과학자들에 의해서도 조장되고 있다. 이러한 분위기 속에서 GMO에 의한 제2 녹색혁명은 Africa 대륙에서의 제1 녹색혁명이 지금도 지연되는 것과 같다고도 볼 수 있다. GMO의 환경에 대한 악영향은 과대 선전되어있는 것이 아닌가? 마치 GMO가 화학비료, 농약제보다 더 위험하다고 믿는 사람들도 많다. 나는 이러한 GMO 공포증이 과학적으로 그리고 "Risk Assessment"의 견지에서 볼 때 그 근거가 희박하다고 보여주는 몇 몇 실험 및 경험 사실들을 인용하려 한다. 그리고 올바른 Risk Assessment야 말로 한국의 21세기 BT 산업을 경쟁력 있게 하고 국민 년 소득 2만불 달성에 중요한 기여를 하게 될 것이라고 생각한다. 한국은 농토가 적고 천연자원이 빈약하다. GMO는 21세기의 생존 경쟁 산업이다. 제2의 녹색혁명은 얼마든지 가능하며, 한국은 부족한 농토와 빈약한 자원에도 불구하고 능력 있는 인적자원이 풍부하여 GMO 개발 연구에 국제적 경쟁력을 키울 수 있다. 그러나 GMO에 대한 논쟁만 하고 있으면 이미 때가 늦는다. 미국은 이미 GMO-BT 시장을 거의 완전 독점했으며, 타국에서의 논쟁과 불합리적으로 엄격한 GMO 관련 규정을 조장하고 환영한다.이상의 결과와 같이 인삼 saponin 성분들은 arachidonic acid로부터 cyclooxygenase를 통해 일단 생성된 endoperoxide에서 각각의 prostagland