레지오넬라균 출현위해도에 대한 현행 온천수 수질기준의 적합성 분석

김진남 ( Jinnam Kim ),이소영 ( Soyoung Lee ),조영근 ( Younggun Zo ) 한국미생물생명공학회(구 한국산업미생물학회) 2015 한국미생물·생명공학회지 Vol.43 No.3

Observed trends in climate change, globalization and an aging population have an effect on public health conditions in Korea, prompting a reevaluation of current environmental regulations. In this study, we evaluated the performance of the total coliform (TC) standard, which is the only microbiological standard in the current regulation regime for hot spring water, by estimating correlation with the presence/absence of Legionella, a non-fecal opportunistic pathogen with heat-tolerance. Microbiological data in 7 studies that surveyed Legionella in hot spring waters were subjected to meta-analyses with the odds ratio (OR) as the effect size. The presence/absence of Legionella was significantly correlated to TC levels [OR = 3.1(1.5-6.4, 95% CI), p = 0.002]. Due to there being no direct explanation as to the reason for the occurrence of TC, mesophilic fecal bacteria, being coupled with Legionella presence, the mechanism of the correlation between the two kinds of bacteria was further investigated. Legionella presence was more prevalent with a high heterotrophic plate count [HPC; 4.0(2.2-7.2); p < 0.001] and water temperature [4.3(1.4-13.6), p = 0.011] when the temperature range was <40oC. However, it was reverse-correlated with water temperature when the temperature was >50oC [0.2(0.1-0.4), p < 0.001]. Therefore, bacterial standing crops in hot spring waters appear to be determined by water temperature in general, and this forces TC and Legionella levels be correlated. In accordance with this relationship, HPC rather than TC reflect the levels of non-fecal contamination better. Therefore, employing HPC as the sole microbiological standard, or adding HPC into the current standard of hot spring water assessment, is suggested as a proactive measure to prevent health issues arising from contamination.

상류에 있는 물체의 직경변화에 따라 후류 물체가 받는 영향

김진남(Jinnam Kim),승삼선(Samsun Seung),김상일(Sangil Kim) 대한기계학회 2014 대한기계학회 춘추학술대회 Vol.2014 No.5

This experimental study is carried out the impacts of a downstream cylinder in the wake change on upstream objects diameter. The V-shaped object is located in the upstream of the test section and the circular cylinder included load-cell is located in the downstream. We investigated the velocity distribution of the wake emitted from the upstream object with changing its diameter. Also the fluctuating lift coefficient and Karman-vortex emission frequency are investigated with changing position of downstream cylinder. They are concluded as followings: i) the flow velocity in the wake is smaller than main stream, ii) the lock-in phenomenon is occurred when the upstream objects diameter is bigger than downstream cylinders one, iii) in order to be maximum fluctuating lift force of the downstream cylinder in the wake, the position of the downstream cylinder must be moved with changing diameter of the upstream object together.

ICT 기반의 LMS를 활용한 군 정신전력 교육 혁신

정상근(Jung Sangkeun),김진남(Kim Jinnam) 국방정신전력원 2021 정신전력연구 Vol.- No.65

이 연구의 목적은 4차 산업혁명의 기술(AI, 빅데이터, 클라우드 등)로 더욱 향상된 ICT(Information and Communication Technology) 기반의 LMS(Learning Management System, 이하 LMS)를 활용하여 정신전력교육의 혁신방안을 제시하는 것이다. 과거 LMS는 E-learning 혹은 on/off line 수업에서 교육을 원활히 진행하도록 돕는 수단 정도로만 인식됐다. 그러나 최근 모바일 기술의 향상과 ICT 기술의 접목으로 LMS는 맞춤형 교육 플랫폼으로 새롭게 진화하고 있다. ICT 기반의 LMS 교육 플랫폼은 클라우드에 다양한 콘텐츠를 축적하고, AI 기술이 수준별‧시기별로 필요한 콘텐츠를 추천하여 맞춤형 학습을 가능하게 하며, 빅데이터 분석을 통해 학습 과정 및 패턴, 학습 목표 달성 등을 실시간으로 분석하여 교육 효과 증대 및 관리 시스템을 혁신적으로 변화시키고 있다. 현재 국내외 많은 대학과 기관에서도 LMS를 활용한 교육을 진행하고 있다. ICT 기반의 LMS 교육 플랫폼의 가장 큰 강점은 교육자와 피교육자 간의 상호작용(interaction)을 증폭시키고, 학습자들을 교육에 보다 능동적으로 참여시킨다는 데에 있다. 또한 최근 코로나-19라는 전대미문의 팬데믹 상황으로 인해 LMS 플랫폼(블랙보드 런, 무들, 캔바스, D2L 등)을 사용하는 대학이 많아지고 있는 상황이다. 이에 우리 군에서 실시하고 있는 정신전력교육도 이러한 사회흐름에 발맞춰 하루빨리 LMS 시스템을 도입할 필요가 있다. 이 연구에서는 먼저 LMS의 개념과 현재 사용실태, 그리고 LMS를 활용한 교육 혁신의 사례를 소개한다. 다음으로 현재 군의 정신전력교육 체계와 교육 효과 및 관리 분야의 제한점을 분석하고, LMS를 적용한 ICT 기반의 정신전력교육 모바일 플랫폼 구성(안)을 제시하였다. 4차 산업혁명이 고도화될수록 사회의 전반적인 교육은 ICT 기반의 모바일 플랫폼 교육으로 계속 발전해나갈 것이다. 군의 여건과 보안 등으로 ICT를 활용한 LMS를 도입하는 것에 많은 우려도 존재하지만, 클라우드를 통한 다양한 교육콘텐츠의 축적, AI를 통한 맞춤형 교육 설계, 빅데이터를 활용한 학습 실태의 실시간 분석 등은 제한점에 따른 우려보다 긍정적인 효과가 더욱 클 것으로 기대된다. The purpose of this study is to present innovation for Military Spirit Education to utilize the improved ICT-based LMS with 4th Industrial Revolution. In the past, LMS was only recognized as a means of helping education in e-learning or on/off line classes. However, with recent advances in mobile technology and the grafting of ICT, LMS is evolving into a customized training platform. ICT-based LMS education platforms are revolutionizing education effectiveness and management system to accumulate various contents in the Cloud, provide contents that someone needs individually by AI technology, and analyze learning processes, patterns and learning goals in real time through Big Data analysis. Currently, many universities and institutions are also conducting education using LMS. The biggest advantage of LMS lies in amplifying the interaction between educators and learners and making them more actively involved in education. In addition, a growing number of universities are using LMS as an unprecedented pandemic called CORONA-19 Virus. Therefore, our Military Spirit Education also needs to be introduced as soon as possible in line with social changes. In this study, we first introduce the concept of LMS, current usage status, and examples of educational innovation using LMS. Next, we analyze the current educational system of our military and its limitations in the field of educational effectiveness and management, and present a mobile platform system with LMS. As the 4th Industrial Revolution is advanced, the overall education of society will continue to develop into ICT-based mobile platform education. There are many concern about the introduction of LMS making use of ICT due to military conditions and security reasons, but the accumulation of various contents through the Cloud, customized education design by AI, and Big Data to analyze actual learning representation will be more positive than concerns.

흡기밸브 타이밍과 리프트 변화가 CAI 엔진의 혼합기 형성에 미치는 영향

사상동(Sangdong Sa),김호영(Hoyoung Kim),김진남(Jinnam Kim),윤석구(Seokgu Yoon) 한국자동차공학회 2007 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

Numerical simulations for the CAI Combustion mode have been conducted to assess the effects of the intake valve timing and lift on overall mixture processes. The distribution of residual gases has a prominent effect on the mixture formation as well as on the gas mean temperature inside a cylinder, the mechanism of which is often used to optimize the negative valve overlap condition. The 3D numerical simulations, based on the Eulerian-Lagrangian two-phase model, have been carried out to account for the mixture processes between an intake-air and hot residual gases. Our simulation results indicate that the amount of back flow is a strong function of the IVO/IVC timing. The heat loss due to escaping gases from the cylinder during secondary backflow causes a moderate decrease of the gas temperature inside the cylinder.

CAI 엔진의 배기밸브 타이밍 변화에 따른 실린더 내 유동 및 혼합 특성에 대한 연구

이주형(Joohyung Lee),김호영(Hoyoung Kim),김진남(Jinnam Kim),김우태(Wootae Kim) 한국자동차공학회 2005 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2005 No.11_1

Recently the environmental pollution becomes serious global problem, so the emission regulation is strengtened. Therefore it is very important to reduce the NOx and particle matter(PM) simultaneously in conventional engines. By this reason, Controlled Auto Ignition(CAI) engines are spotlighted because it reduced NOx and PM simultaneously. There are some indirect method to control the auto ignition, using low vapor pressure fuel, controling the fuel injection timing, increasing intake air temperature and compression ratio, and increasing charged gas temperature by internal EGR.<br/> This paper reports the effects of exhaust valve timing on the flow and mixing characteristics of CAI engine. Controling EVC is more effective method to the fraction and uniformity of internal EGR than controling EVO. Retarding EVC, mean temperature, internal EGR fraction is decreased, but uniformity is increased.

GDI 엔진의 PN 생성 원인 규명 및 저감에 대한 연구

유철호(Chulho Yu),조윤호(Yoonho Cho),김진남(Jinnam Kim),황인구(Ingoo Hwang),오대윤(Daeyoon Oh) 한국자동차공학회 2012 한국자동차공학회 부문종합 학술대회 Vol.2012 No.5

Fuel injected directly in cylinder in Gasoline Direct Injection engine is changed partly to particulate. It mast be reduced to meet the regulation of particulate number in EURO 6. Particulate is created in diffusion flame of wall wetting piston and combustion chamber roof, fuel deposits around injector tip, residual fuel droplets during combustion and also in the inhomogeneous gas phase around local rich area and the stored fuel in fire land. PN level can be reduced by the optimization of mapping parameter, the increase of injection pressure, multiple injection and laser drilled injection hole in injector. Also, MPI injectors are installed in ports together with GDI injectors and are used in the area that emits a lot of particulate instead of or together with GDI injectors. The source and emission level of particulate in GDI engine is investigated and the methods for reducing particulate are investigated in the paper.

2.5L 신규 하이브리드 엔진 개발을 위한 연소 시스템 최적화

박종국(Jongguk Park),오희창(Heechang Oh),임현준(Hyunjun Im),박준호(Joonho Park),김진남(Jinnam Kim),임혁(Hyuk Im) 한국자동차공학회 2024 한국자동차공학회 부문종합 학술대회 Vol.2024 No.6