• 한국환경과학회지
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• 제24권1호
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• pp.73-79
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• 2015

The objective of this work was to treat complex mal-odor of food waste with micro-bubbles from enhanced wet scrubber system, where the pilot plant was operated. Micro bubbles from the enhanced reactor of venturi scrubber were successfully generated through the air atomizing process with high velocity more than 60 m/sec and played an important role in the removal of mal-odor. Mal-odor was effectively changed into the micro-bubble and treated with washing chemicals together. Through establishing two series connection of the reactors, 85.2 % removal efficiency of complex mal-odor was obtained in case of average 940 times of input air. 0.35 kg/hr of sulfuric acid, 0.188 kg/hr of sodium hydroxide and 0.043 kg/hr of hypochlorite were injected for chemical washing.

• 한국환경과학회지
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• 제3권2호
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• pp.157-164
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• 1994

Various antimicrobial agents are widely used for the purpose of antimicrobial process. We investigated antimicrobial activity and reduction efficiency of mal-ordour by the diphenyl ether compound (2,4,4'- trichloro -2'- hydroxy diphenyl ether) against Sraphylocom aureus(S.aureus and Proton vulgaris(p.vulgaris causing the mal-ordour, Especially, the diphenyl ether compound is not restricted to the regulation of water-contamination. In this research, we found that the optimum concentration of diphenyl ether compound was 1.5w% for both strains and antimicrobial expressions were c0.38t= 2.56 for S.aureus, c0.38t=2.67 for P.vulgaris. We found also that -OH group played the role of antimicrobial functional group. Lastly, reduction effect of mal-ordour was more than 90% for both strain at the optimum conditions. Key Words : antimicrobial agents, antimicrobial activity, reduction effect of mal-ordour, antimicrobial expression, antimicrobial functional group.

• Advances in nano research
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• 제11권6호
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• pp.667-678
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• 2021

Multiwalled carbon nanotubes (MWCNTs) were first oxidized (O-CNTs) to introduce carboxylic group and then further functionalized (F-CNTs) with m-phenylenediamine, which was confirmed by FTIR and SEM. It was used as an effective adsorbent for the adsorptive removal of diclofenac drug from water. Under optimum conditions of pH 6, stirring speed 600 rpm, the maximum adsorption capacity obtained was 532 mg g^-1 which is superior to the values reported in literature. The adsorption was quite rapid as 25 mg L^-1 drug solution was adsorbed in only 3 minutes of contact time with 10 mg of adsorbent dose. The adsorption kinetics and isotherms were studied using various models to evaluate the adsorption process. The results showed that the data best fit in kinetics pseudo-second order and Langmuir isotherm model. Furthermore, the oxidized and functionalized MWCNTs were applied on gram-negative Escherichia coli and gram-positive Staphylococcus aureus using agar disc diffusion assay to validate their anti-microbial activity. Results were unique as both oxidized and functionalized MWCNTs were equally active against both E. coli and S. aureus. The newly synthesized F-CNTs have great potential in water treatment, with their dual action of removing drug and pathogens from water, makes it potential applicant to save environment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권5호
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• pp.1466-1488
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• 2022

Recently, the importance and necessity of artificial intelligence (AI), especially machine learning, has been emphasized. In fact, studies are actively underway to solve complex and challenging problems through the use of AI systems, such as intelligent CCTVs, intelligent AI security systems, and AI surgical robots. Information security that involves analysis and response to security vulnerabilities of software is no exception to this and is recognized as one of the fields wherein significant results are expected when AI is applied. This is because the frequency of malware incidents is gradually increasing, and the available security technologies are limited with regard to the use of software security experts or source code analysis tools. We conducted a study on MalDC, a technique that converts malware into images using machine learning, MalDC showed good performance and was able to analyze and classify different types of malware. MalDC applies a preprocessing step to minimize the noise generated in the image conversion process and employs an image augmentation technique to reinforce the insufficient dataset, thus improving the accuracy of the malware classification. To verify the feasibility of our method, we tested the malware classification technique used by MalDC on a dataset provided by Microsoft and malware data collected by the Korea Internet & Security Agency (KISA). Consequently, an accuracy of 97% was achieved.

• 대한안전경영과학회지
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• 제9권6호
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• pp.171-179
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• 2007

The objective of this GM Red-X project was to reduce customer complaints on Kalos, Lacetti, Magnus as reported through 2004.1 - 2005.1 warranty performance. Seatbelt alarm lamp mal-function problem is connected with safety. So it is critical issue. Seatbelt alarm lamp mal-function which caused by buckle occurred 22 cases from 2004.1 to 2005.1.

• Journal of Electrical Engineering and Technology
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• 제11권3호
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• pp.585-591
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• 2016

DOCR can be used to efficiently increase the reliability and to protect the bi-directional D/L(Distribution Lines). As more DG(Distributed Generation)s attempt to connect the bi-directional D/L, there is an increasing need for studies of how to use DOCR installed in the D/L. This paper investigates the operating principles of DOCR and presents the results an effect of sequence and fault impedance in L-L(Line to Line) fault. An advanced DOCR operating algorithm is proposed to reduce the mal-operation of conventional DOCR. The proposed algorithm is applied to the bi-directional power flow system and shows that it decreases the mal-operation of DOCR through the computer simulation.

• 한국정보교육학회:학술대회논문집
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• 한국정보교육학회 2007년도 동계학술대회
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• pp.209-216
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• 2007

고도의 지식정보사회 속에서 논리적 사고력과 창의력, 문제해결력을 길러주는 프로그래밍 교육의 필요성은 더욱 강조되고 있다. 이에 본 연구에서는 초등학생들에게 적합한 교육용 프로그래밍 언어인 JavaMAL을 활용하여, 프로그래밍의 함수개념 형성을 위한 학습모형을 구안 적용하고 일반화 가능성을 탐색하고자 하였다. 먼저 기초적인 프로그래밍 요소 중 함수개념과 관련된 학습요소를 추출하여 차시별 지도계획을 수립하였다. 또한, 프로그래밍의 함수가 수학적 함수의 모방이라는 것에 착안하여 수학의 '규칙성과 함수'지도 단계를 LOGO의 문제해결력 수업모형인 안내된 발견식 교수법(guided discovery teaching method)에 강화한 후, 인터넷을 활용한 문제해결 수업모형을 구안하였다. 기본명령어와 변수개념을 이미 익힌 계발활동 부서 6학년 아동들을 지도 대상으로 한 달간 웹 기반 JavaMAL 환경에서 학습할 수 있도록 하였으며, 게시판 활동 및 활동지를 통해 함수개념 형성 여부를 측정하였다.

• 한국미생물·생명공학회지
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• 제46권1호
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• pp.29-39
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• 2018

Vibrio vulnificus needs various responsive mechanisms to survive and transmit successfully in alternative niches of human and marine environments, and to ensure the acquisition of steady energy supply to facilitate such unique life style. The bacterium had genetic constitution very different from that of Escherichia coli regarding metabolism of glycogen, a major energy reserve. V. vulnificus accumulated more glycogen than other bacteria and at various levels according to culture medium and carbon source supplied in excess. Glycogen was accumulated to the highest level in Luria-Bertani (3.08 mg/mg protein) and heart infusion (4.30 mg/mg protein) complex media supplemented with 1% (w/v) maltodextrin at 3 h into the stationary phase. Regarding effect of carbon source, more glycogen was accumulated when maltodextrin (2.34 mg/mg protein) was added than when glucose or maltose (0.78.1-14 mg/mg protein) was added as an excessive carbon source to M9 minimal medium, suggesting that maltodextrin metabolism might affect glycogen metabolism very closely. These results were supported by the analysis using the malP (encoding a maltodextrin phosphorylase) and malQ (encoding a 4-${\alpha}$-glucanotransferase) mutants, which accumulated much less glycogen than wild type when either glucose or maltodextrin was supplied as an excessive carbon source, but at different levels (3.1-80.3% of wild type glycogen). Therefore, multiple pathways for glycogen metabolism were likely to function in V. vulnificus and that responding to maltodextrin might be more efficient in synthesizing glycogen. All of the glycogen samples from 3 V. vulnificus strains under various conditions showed a narrow side chain length distribution with short chains (G4-G6) as major ones. Not only the comparatively large accumulation volume but also the structure of glycogen in V. vulnificus, compared to other bacteria, may explain durability of the bacterium in external environment.

• 한국해양학회지:바다
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• 제8권1호
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• pp.29-34
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• 2003

한국 서해의 곰소만에서 분리한 온대 해역 산 초유의 M. rubrum MR-MAL01 배양체가 확보되어, M. rubrum의 입자성 먹이 섭식 현상이 보고되었다. 100$\mu$mo1 photons m$^{-2}$ s$^{-1}$의 고광도(HL) 및 10 $\mu$mo1 photons m$^{-2}$ s$^{-1}$의 저광도(LL)에서 광 적응된 미동정 은편모조류 종주 CR-MAL01를 섭식한 M. rubrum의 HL및 LL적응 배양체의 흡광스펙트림을 분석하였다. LL에 적응된 은편모조류를 섭식하고 LL에 적응한 M. rubrum은 섭식 이전의 먹이 세포 흡광특성인 542nm부근의 황갈색 파장 범위에서 뚜렷한 흡광피크를 나타낸 반면, HL에 적응된 은편모조류를 섭식하고 HL에 적응한 M. rubrum은 이러한 흡광 피크를 보이지 않았다. 이는 M. rubrum세포가 자연환경에서 먹이로서 은편모조류 세포를 섭식하기 이전 이들의 광 적응 상태가 섭식 이후 M. rubrum의 광이용 효율 및 광흡수 특성 등을 결정짓는 주요 요인이 될 가능성을 시사한다. 본 연구 결과에 따라 예상되는 해양 미소생물 생태계 내에서 이들 섭식자 및 먹이생물 종의 역할에 대하여 논의하였다.

• 한국양식학회지
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• 제17권2호
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• pp.115-121
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• 2004

최근, 곰소만에서 채집한 시료로부터 최초의 온대역산 광합성 섬모류 Mesodinium rubrum MR-MAL01 배양체를 분리ㆍ배양하였다. 이 섬모류를 이용하여 이매패류의 섭식실험을 수행한 결과, 비단가리비와 바지락과 같은 이매패류가 섬모류를 직접 섭식 하였음을 확인하였는데, 개체 당 최대 섭식률은 비단가리비 9,590 cells $min^{-1}$, 바지락 23,200 cells $min^{-1}$으로 나타났다. 또한 비단가리비의 소화관에서 완전한 M. rubrum세포를 확인하지 못했으나, 파괴된 세포로 생각되는 작은 입자들을 관찰하였다. 바지락 치패에 섬모류인 M. rubrum과 미소조류인 Isochrysis galbana (KMCC H-2)를 공급하면서 28일 동안 사육한 결과, 작은 치패 그룹(각장 0.46 mm)에서는 I. galbana를 공급한 실험구가 좋은 성장을 보였던 반면, 큰 치패 그룹(각장 0.84 mm)에서는 M. rubrum을 공급한 실험구가 I. galbana를 공급한 실험구에 비해 성장이 좋았다. 따라서 이 광합성 섬모류는 이매패류의 치패 및 모패와 입이 작은 자어의 먹이생물, rotifer의 영양강화제 및 어류의 천연 착색제로도 활용할 수 있는 잠재력이 있어 해양 생물공학적 활용을 위한 생물재료로서 개발 가능성을 제안한다.