• Korean Journal of Poultry Science
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• v.31 no.4
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• pp.293-298
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• 2004

Microinjection of DNA is a general method for generating transgenic animals, but the rate of transgenesis in chickens is very low. So it was carried out to investigate the efficiency of liposome-mediated gene transfer in stage one cell of chicken embryo with GFP expression vector. In order to determine efficiency and duration of the introduced foreign gene, it was microinjected DNA with liposome or naked DNA into the germinal disc of stage one cell or stage-X chicken embryo. Analysis of reporter gene expression in day-4 embryos showed that GFP expression was observed only in the liposome-mediate embryo groups and detectable up to day-8 embryos. The results suggest that stable integration of the introduced gene using liposome is a rare event. Nevertheless the liposome-mediated gene transfer may be a useful method to transfer a foreign gene into the stage one cell of chicken embryos.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.1
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• pp.132-137
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• 2003

This study was carried out to investigate removal character of nitrogen and phosphorus with injection time of acetic acid on SBR, which is one of the biological treatment process. Wastewater used in experiment period was swine wastewater with character, relatively lower organic material concentration than nitrogen concentration. In the experiment with injection time of acetic acid, run 1 wasn't injected acetic acid during the anoxic period, and run 2 was injected intermittently acetic acid during the anoxic period of 15 hours. And run 3 was injected intermittently during the anoxic period of 3hours from end of wastewater filling. And filing time of the wastewater was 20hour from run 1 to run 3. In the study, the highest removal efficiency of organic and nitrogen were obtained by the operating condition of Run 2(the ratio of mixing/aeration time : 16.5/5.5, injection time of acetic acid : 15hours) and T-P was obtained by the operation condition of Run 3(the ratio of mixing/aeration time : 16.5/5.5, injection time of acetic acid : 3hours),and removal efficiency of $BOD_5$, $COD_{Mn}$, $COD_{Cr}$, T-N and T-P in the treated water was 96.1%, 87.7%, 90.6%, 86.6% and 84.5%, respectively.

• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.641-650
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• 2022

The purpose of this study was to compare the efficiency of air and oxygen injected into the underwater non-thermal dielectric barrier discharge plasma (DBD plasma) device used to remove five types of antibiotics (tetracycline, doxycycline, oxytetracycline, clindamycin, and erythromycin) artificially contained in the fish farm discharge water. The voltage given to generate DBD plasma was 27.8 kV, and the measurement intervals were 0, 0.5, 1, 2, 4, 8, 16 and 32 minutes. Tetracycline antibiotics significantly decreased in 4 minutes when air was injected and were reduced in 30 seconds when oxygen was injected. After the introduction of air and oxygen at 32 minutes, 78.1% and 95.8% of tetracycline were removed, 77.1% and 96.3% of doxycycline were removed, and 77.1% and 95.5% of oxytetracycline were removed, respectively. In air and oxygen, 59.6% and 83.0% of clindamycin and 53.3% and 74.3% of erythromycin were removed, respectively. The two antibiotics showed lower removal efficiency than tetracyclines. In conclusion, fish farm discharge water contains five different types of antibiotics that can be reduced using underwater DBD plasma, and oxygen gas injection outperformed air in terms of removal efficiency.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.3
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• pp.203-207
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• 2009

The concern of seriousness and harmful effects of environmental pollution is rising by the various water pollutions, appearances of new micro-noxious substances and increase of sustainable pollutants. The method is suggested that can effectively increase the removal of organic substances and several pollutants using a coagulation process. The experiment for characteristics of $ZrSiO_4$ (zirconium silicate) as a coagulation-aid was carried out for application to coagulation process with domestic wastewater and lake water, and the removal rate of the organic substances depending on a dosage was evaluated by PDA (Photometric Dispersion Analyzer) in this study. Zeta-potential of zirconium silicate solution was -32.22 mv at pH 7 and the lower negative(-) charge was detected in the more acidic conditions. Absorbance on $UV_{254}$ presented higher when zirconium silicate was added than in a domestic wastewater itself. Besides, the results by PDA experiment represented that injection of zirconium silicate could promote growing of floc. Tests for coagulation process were conducted by three ways which are pre-injection, co-injection and post-injection of zirconium silicate with alum. Accordingly, removal efficiency of organic substances increased over 15% in co-injection than in using of alum as a sole reagent. When a 20 mg/L of alum was used with a 10 mg/L of zirconium silicate, the removal efficiency was high up to 90%. Removal efficiency of $COD_{Cr}$ was improved more than 15% in case of dosage of coagulant either PAC (Poly aluminium chloride) or PACS (Poly aluminium chloride Silicate) together with zirconium silicate. As a result, the removal efficiency of $COD_{Cr}$ were 5~10% higher in a co-injection of zirconium silicate with a coagulant than a pre-injection and a post-injection but it of soluble substances was lower in a co-injection.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.3
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• pp.551-561
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• 2018

As the computational technology using quantum computing has been developed, several threats on cryptographic systems are recently increasing. Therefore, many researches on post-quantum cryptosystems which can withstand the analysis attacks using quantum computers are actively underway. Nevertheless, the lattice-based NTRU system, one of the post-quantum cryptosystems, is pointed out that it may be vulnerable to the fault injection attack which uses the weakness of implementation of NTRU. In this paper, we investigate the fault injection attacks and their previous countermeasures on the NTRU signature system and propose a secure and efficient countermeasure to defeat it. As a simulation result, the proposed countermeasure has high fault detection ratio and low implementation costs.

• Resources Recycling
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• v.21 no.4
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• pp.69-75
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• 2012

Destruction of HFC-134a from ELV (End of Life Vehicle) were determined in a gasification-melting demonstration system of municipal solid waste (100ton/day). The injection system has been developed for the uniform injection of HFC-134a to the gasification-melting system. The destruction characteristics of HFC-134a and analysis of exhaust gases have been performed. The destruction efficiency was 99.995% for HFC-134a feeding of 3 kg/hr and the exhaust gases such as CO, SOx, NOx, HCl and HF satisfied the environmental standards.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.339-343
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• 2006

전기발광소자는 바이폴라소자로서 전자와 정공의 주입, 이동 및 재결합에 의하여 발광한다. 소자에 사용되는 발광층의 대표 물질인 $Alq_3$를 한층(single layer)만 사용하고 정공의 주입을 도와주기위하여 폴리테트라플로로에틸렌(테플론)층을 얇게 증착하여 두께 변화에 따른 소자의 전기적 발광 특성을 측정하였다. 테플론은 좋은 부도체 폴리머로서 정공 터널링 전류가 두께 2 nm에서 가장 크게 증가하였으며 효율도 최대에 이르렀다. 주사전자현미경을 이용하여 실리콘 기판에 증착시킨 테플론 박막의 조직을 조사한 결과 두꺼워 질수록 라멜라(섬유조직)가 발달함을 알 수 있었다. 전자 주입을 도와주는 터널링층으로서 알루미늄산화막을 $Alq_3$ 위에 3 ${\AA}$ 증착한 결과 전류와 효율이 더 증가하였다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.194-197
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• 2001

본 연구에서는 유류 오염토양 복원을 위한 효율적인 이동형 연속식 토양세척 장비를 개발하여 현장 적용 가능성을 검토하였다. 진세척조는 내부에 스크류를 설치함으로써 주입되는 오염토양과 세척용액의 기계적 교반에 의한 원활한 접촉과 토양간의 마찰 등으로 인하여 토양으로부터 오염물질의 탈착이 효과적으로 이루어지도록 하였다. 전세척조 외부에 위치한 주세척조는 전세척조에서 탈착된 오염물질과 미세입자를 원 토양으로부터 효율적으로 분리하기 위한 헹굼작용과 배출부에서 미세입자를 포함하는 세척 유출수가 효율적으로 분리 배출이 될 수 있도록 설계.제작하였다. 현장 적용 실험결과, 설계 목표치인 토양 주입 속도 15m$^3$/day, 계면활성제 POE$_{5}$POE$_{14}$의 비 1:1 (농도 0.1%), 세척수/토양 비 (부피/중량비) 1, 전세척조 회전속도 18rpm. 주세척조 회전속도 5rpm의 운전조건에서 90% 이상의 높은 세척효율을 나타내었다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.85-86
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• 2014

본 연구에서는 유입수의 변동이 심하고 전문가가 부재한 환경인 선박에서 발생하는 오수의 효과적인 처리를 위하여 RCM공법을 선박오수처리장치에 적용하는 실험실 규모의 실험을 수행하였다. 질소 인의 고도처리 효율과 선박이라는 특수환경과의 접목성을 검토한 결과 RCM공정에 유효미생물을 주입하는 방법은 선박환경에 적합한 것으로 평가되었다. 또한 RCM공정은 활성슬러지 공정에서 배출되는 슬러지는 배출시키지 않고 슬러지액화분해조(SDC)에서 재분해하여 순환함으로써, 최근 해양투기가 금지됨으로 인해 문제가 되고 있는 슬러지의 발생량을 최소한으로 하여 친환경적인 수처리가 가능하다. 복합미생물제제 주입 후 미생물 관찰결과 고도처리에 유리한 미생물종의 출현을 확인하였으며 이들의 상호기작으로 질소 인의 처리에 도움을 주어 처리효율이 높은것이라 판단된다. 유기물 제거효율 실험결과 $BOD_5$, CODcr T-N, T-P의 처리효율이 각각 96, 97, 78, 81.68 %로 나타나 Membrane이나 Filter없이도 강화되어가는 해양오염기준을 충족시킬 수 있는 공정으로 판단된다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.185-185
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• 2010

유기 발광 소자에서 $Li_2CO_3$를 전자 주입층으로 사용하여 전류, 전압, 휘도 그리고 수명을 살펴 보았다. 전자 주입층을 사용함으로써 음전극과 전자 수송층 사이의 전자 주입의 에너지 장벽을 낮출 수 있다. 전자 주입층에 Ca, Mg, Li 등과 같은 낮은 일 함수의 금속을 사용하면, 음전극과 유기물층 사이의 효과적인 전자 주입을 도울 수 있다. 소자의 구조는ITO/TPD(40nm)/$Alq_3$(60nm)/$Li_2CO_3$(xnm)/Al(100nm)으로 하였으며, $Li_2CO_3$의 두께를 0.1, 0.2, 0.3, 0.5, 0.7, 0.9, 1.2, l.5nm로 변화시켜 소자를 제작하였다. $Li_2CO_3$의 박막 두께가 0.3nm일 때, 전자 주입층을 사용하지 않은 소자에 비하여 효율은 2.4배 증가하였고, 구동전압은 0.75V 낮아졌다.