전자식 선박디젤엔진의 엔진제어기 개발/연구

심한섭(Han-Sub Sim),이민광(Min-Kwang Lee),이강윤(Kang-Yoon Lee) 한국기계가공학회 2015 한국기계가공학회지 Vol.14 No.5

A control program of an engine control module (ECM) was developed, and its control performance was verified on a 750Ps marine diesel engine. The control method was designed for an engine rotational speed control system. For ECM hardware, the commercial rapid control prototype (RCP) ECM was used. The programming tool for control algorithm development was the MatLab/Simulink. The main control algorithm assembled many control models as engine cranking, run, and stall. Each model has sub-models to input/output control signals. The target engine speed was input signal from a speed control lever, and control output signal of the ECM was sent to the unit-injectors for fuel injection. The engine test was performed under various conditions of engine rotational speeds and dynamometer loads. The test results show that the control function of the ECM is suitable for electrical marine diesel engines.

Three Temperature Model for Nonequilibrium Energy Transfer in Semiconductor Films Irradiated with Short Pulse Lasers

Lee, Seong Hyuk,Sim, Hyung Sub,Lee, Junghee,Kim, Jong Min,Shin, Young Eui The Japan Institute of Metals 2006 MATERIALS TRANSACTIONS Vol.47 No.11

<P>This article investigates numerically carrier-phonon interaction and nonequilibrium energy transfer in direct and indirect bandgap semiconductors during sub-picosecond pulse laser irradiation and also examines the recombination effects on energy transport from the microscopic viewpoint. In addition, the influence of laser fluence and pulse duration is studied by using the self-consistent three-temperature model, which involves carriers, longitudinal optical phonons, and acoustic phonons. It is found that a substantial non-equilibrium state exists between carriers and phonons during short pulse laser irradiation because of time scale difference between the relaxation time and the pulse duration. It is clear that the two-peak structure in carrier temperature exists and it depends mainly on laser pulses, fluences, and recombination processes. During laser irradiation, in particular, the Auger recombination for Si becomes dominant due to the increase in the carrier number density, whereas for GaAs, the Auger recombination process can be ignored due to an abrupt increase in SRH recombination rates at the initial stages of laser exposure.</P>

혈갈(Draconis Sanguis)의 항산화와 사람섬유아세포에서 MMP-1 발현저해 효과

심관섭 ( Gwan Sub Sim ),김진희 ( Jin Hui Kim ),김진화 ( Jin Hwa Kim ),이동환 ( Dong Hwan Lee ),박성민 ( Sung Min Park ),이범천 ( Bum Chun Lee ),표형배 ( Hyeong Bae Pyo ) 대한화장품학회 2004 대한화장품학회지 Vol.30 No.4

태양광선에 노출된 피부에서는 자외선의 작용으로 활성산소종이 생성되어 세포외 기질 및 피부세포에 손상을 야기시킨다. 특히 자외선에 의해 손상을 받은 피부는 콜라겐 등의 세포외 기질에 영향을 주어 주름을 형성하는데, 이는 자외선에 의해 피부내에서 콜라겐을 분해하는 효소(MMP)의 양이 증가하기 때문이라고 알려져 있다. 따라서, 활성산소종 소거 및 MMP의 발현을 저해하여 광노화로부터 피부를 보호할 수 있을 것으로 기대된다. 본 연구에서는 광노화와 연관하여 혈갈의 기능을 알아보기 위하여 항산화 효과, in vitro MMP활성 저해능, 자외선 조사에 의해 유도된 MMP-1 발현에 대한 영향을 사람섬유아세포를 이용하여 확인하였다. 혈갈의 항산화 효과를 알아보기 위해 DPPH radical과 superoxide anion radical 소거효과를 측정하였다. 그 결과 DPPH radical의 IC₅₀ 값은 183 ㎍/mL이고, xanthine/xanthine oxidase에 의한 superoxide anion radical의 IC₅₀ 값은 30 ㎍/mL이었다. MMP-1의 활성저해 결과는 농도 의존적으로 활성을 억제하였으며, IC₅₀ 값은 200 ㎍/mL이다. 또한 자외선 조사에 의해 발현되는 MMP-1에 대해 단백질의 앙적인 변화는 74% 감소되었으며, 혈갈에 의해 농도 의존적으로 MMP-1 mRHA의 발현량도 감소되었다. 이러한 실험결과를 통하여 혈갈은 항산화 효과 뿐만 아니라 자외선 조사에 의해 유도되는 MMP-1 단백질 발현과 mRNA 유전자 수준에서의 조절이 가능함을 확인하였다. 결론적으로 혈갈은 항산화와 자외선으로부터 생성되는 MMP-1의 발현을 저해함으로써 광노화에 따른 피부를 보호하는 항노화 소재로서의 응용가능성을 확인하였다. UV irradiation produces free radicals and related reactive oxygen species (ROS), and these are injury to all most of organisms of skin cells and extracellular matrix (ECM). In addition, free radicals and ROS stimulate the overexpression of matrix metalloproteinases (MMPs) that can degrade most components of ECM such as collagen. Since collagen constitutes almost of skin connective tissue, their disarrangement causes wrinkle formation and droop of skin. Therefore, scavenging activity on free radicals, ROS and suppression of MMP-1 is expected to prevent skin photoaging. In this study, to investigate the relationship between photoaging and Draconis sanguis, we examined the effects of antioxidant, in vitro MMP inhibition and expression of UVA-induced MMP-1 in human dermal fibroblasts. Draconis sanguis was found to show scavenging activities of radicals and ROS with the IC₅₀ values of 183 ㎍/mL against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 30 ㎍/mL against superoxide radicals in the xanthine/xanthine oxidase system, respectively. Draconis sunguis inhibited the activities of MMP-1 in a does-dependent manner and the IC₅₀ value calculated from semi-log plots was 200 ㎍/mL. Also, UVA induced MMP expression was reduced 74% by treatment with Draconis sanguis, and MMP-1 mRNA expression was reduced in a dose-dependent manner. Therefore Draconis sanguis was able to significantly inhibit MMP expression in protein and mRNA level. All these results suggested that Draconis sanguis may act as an anti-photoaging agent by antioxidation and reducing UVA-induced MMP-1 production.

약용식물추출물의 광보호 효과와 항염증 효과 연구

김진화 ( Jin-hwa Kim ),박성민 ( Sung-min Park ),심관섭 ( Gwan-sub Sim ),이범천 ( Bum-chun Lee ),표형배 ( Hyeong-bae Pyo ) 대한화장품학회 2004 대한화장품학회지 Vol.30 No.2

자외선이 피부에 지속적으로 조사되면 썬번, 염증, 광노화와 같은 다양한 부작용이 생기게 된다. 따라서 광손상에 대한 보호작용은 점점 중요성이 인식되고 있으며, 천연 식물추출물에서 자외선에 대한 광보호효과가 있는 안전하고 효과적인 물질개발에 대한 연구가 진행되고 있다. 본 연구는 자외선에 의해 유도된 피부손상에 대한 보호효과가 우수한 천연식물추출물에 대한 것이다. 향나무, 능소화, 비자추출물에서 자외선에 의해 생성되는 라디칼에 대한 항산화효과, MMP 발현 및 활성 저해, 염증관련 사이토카인인 인터루킨 1 알파, 6, 프로스타글란딘 E₂ 생성저해효과 등으로 피부세포보호 효과를 연구하였다. 실험결과 천연추출물 중 향나무추출물과 능소화추출물이 프리라디칼 및 슈퍼옥사이드 라디칼 소거효과가 우수하게 나타났으며 피부 콜라겐과 같은 메트릭스를 분해하는 효소인 MMP-1의 활성 및 발현 저해효과는 섬유아세포에서 UVA 조사에 의한 실험에서 우수하게 나타났으며, 피부세포 배양액에 대해 zymography를 실시하여 활성이 감소됨을 확인하였다. 피부 각질형성세포에서 자외선에 의해 유도된 염증관련 사이토카인인 인터루킨 6의 발현량 실험에서도 무처리군에 비해 향나무추출물이 인터루킨 6을 30% 정도 저해효과가 나타났으며, 염증반응 중 cyclooxygenase (COX)에 의한 경로에서 생성되는 프로스타글란딘 E₂의 생성량도 감소시켰다. 사람피부에서 SLS (0.5%) 첩포로 유발된 자극성 피부염의 항염증 효과 평가 시 SLS에 의해 유발되는 자극정도가 피검자의 피부상태에 따라 다양하게 나타났으며, 향나무 추출물 함유 에멀젼 제품 도포 실험에서는 피부 홍반 완화 효과와 피부장벽 회복효과가 우수하게 나타났다. 이상의 결과로 향나무추출물은 자외선 조사 및 SLS에 의한 피부손상에 대한 피부세포보호작용이 우수하여 광노화에 대응하는 자극완화 소재로서의 화장품 응용 가능성을 확인하였다. Chronic exposure to solar radiation, particularly ultraviolet (UV) light, causes a variety of adverse reactions on human skin, such as sunburn, photoaging and photocarcinogenesis. Free radicals and reactive oxygen species (ROS) caused by UV exposure or other environmental facts play critical roles in cellular damage. And, repeated-UV irradiation activated the expression of the matrix metalloproteinase (MMP) and induced skin irritation. Therefore, the development of effective and safe photoprotectants that can reduce and improve the skin damage has been required. The purpose of this study was to investigate the photo-protective effect of several chinese medical plants (Juniperus chinensis) on the UV -induced skin cell damages. We tested free radical and superoxide scavenging effect in vitro. Fluorometric assays of the proteolytic activities of MMP-1 (collagenase) were performed using fluorescent collagen substrates. UVA induced MMP-1 synthesis and activity were analyzed by enzyme-linked immunosorbent assay (ELISA) and gelatin-based zymography in skin fibroblasts. We also examined anti-inflammatory effects by the determination test of proinflammatory cytokine, interleukin 6 in HaCaT keratinocytes. Expression of prostaglandin E₂ (PGE₂) after UVB irradiation was measured by competitive enzyme immunoassay (EIA) using PGE₂ monoclonal antibody. In the human skin we tested anti-irritation effect on the SLS-induced damage skin after appling the extract containing emulsion. We found that Juniperus chinensis extract had potent radical scavenging effect by 98% at 100 ㎍/mL. The extract of Juniperus chinensis showed strong inhibitory effect on MMP-1 activities by 97% at 100 ㎍/mL and suppressed the UVA induced expression of MMP-1 by 79% at 25 ㎍/mL. This extract also showed strong inhibition on MMP-2 activity in UVA irradiated fibroblast by zymography. In the test of proinflammatory cytokines of human keratinocytes Juniperus chinensis extract decreased expression of interleukin 6 about 30%. The amount of PGE₂ by HaCaT keratinocytes was significantly increased at the doses of above 10 mJ/㎠ of UVB (p < 0.05). At the concentrations of 3.2~25 ㎍/mL of this extract, the production of PGE₂ by HaCaT keratinocytes (24 h after 10mJ/㎠ UVB irradiation) was significantly inhibited in culture supernatants (p < 0.05). In SLS-induced skin irritation model in vivo, we found to reduce skin erythema and improve barrier recovery after appling Juniperus chinensis extract containing emulsion when compared to irritated non-treated and placebo-treated skin. Our results suggest that Juniperus chinensis extract can be effectively used for the prevention of UV and SLS-induced adverse skin reactions and applied as anti-aging and anti-irritation cosmetics.

향나무추출물의 광손상으로부터 피부세포 보호와 자극완화 효과에 대한 연구

김진화 ( Jin-hwa Kim ),박성민 ( Sung-min Park ),심관섭 ( Gwan-sub Sim ),이범천 ( Bum-chun Lee ),표형배 ( Hyeong-bae Pyo ) 대한화장품학회 2004 대한화장품학회지 Vol.30 No.1

태양광선과 산소는 피부세포에 자유라디칼(free radical)과 활성산소종(Reactive oxygen species, ROS)을 생성시켜 DNA의 손상과 세포막 지질의 과산화를 유발한다. 또한 콜라겐과 같은 세포 외 기질을 파괴하는데 관여하는 효소(matrix metallo-proteinhse, MMPs)의 발현에 영향을 주어, 결합조직을 손상시키며, 피부 염증을 유발시켜 조직을 파괴하고 노화를 가속화시킨다. 본 연구는 자외선과 SLS에 의한 피부손상에 대한 향나무추물물의 피부 보호 효과에 대한 것이다. 실험 결과 프리라디칼 및 슈퍼옥사이드 라디칼 소거 효과가 우수하게 나타났으며, 피부 콜라겐과 같은 메트릭스를 분해하는 효소인 MMP-1의 활성 및 발현 저해 효과는 섬유아세포에서 UVA 조사에 의한 실험에서 우수하게 나타났으며, 피부세포 배양액에 대해 zymography를 실시하여 활성이 감소됨을 확인하였다. 피부 각질형성세포에서 자외선에 의해 유도된 염증관련 사이토카인인 인터루킨 6의 발현량 실험에서도 무처리군에 비해 향나무추출물이 인터루킨 6를 30% 정도 저해효과가 나타났으며, 염증반응 중 cyclooxygenase (COX)에 의한 경로에서 생성되는 프로스타글란딘 E₂의 생성량도 감소시켰다. 사람 피부에서 SLS (0.5%)첩포로 유발된 자극성 피부염의 항염증 효과 평가 시 SLS에 의해 유발되는 자극정도가 피검자의 피부상태에 따라 다양하게 나타났으며, 향나무추출물 함유 에멀젼 제품 도포 실험에서는 피부 홍반 완화 효과와 피부장벽 회복 효과가 우수하게 나타났다. 따라서 향나무추출물은 자외선 조사 및 SLS에 의한 피부손상에 대한 보호 효과를 가진 화장품에서 우수한 소재로 적용될 수 있다. The human skin is constantly exposed to environmental irritants such as ultraviolet, smoke, chemicals. Free radicals and reactive oxygen species (ROS) caused by these environmental facts play critical roles in cellular damage. These irritants are in themselves damaging to the skin structure but they also participate the immensely complex inflammatory reaction. The purpose of this study was to investigate the skin cell protective effect of Juniperus chinensis xylem extract on the UV and SLS-induced skin cell damages. We tested free radical and superoxide scavenging effect in vitro. We found that Juniperus chinensis xylem extracts had potent radical scavenging effect by 98% at 100 ㎍/mL. Fluorometric assays of the proteolytic activities of matrix metalloproteinase-l(MMP-1, collagenase) were performed using fluorescent collagen substrates. UV A induced MMP-1 synthesis and activity were analyzed by enzyme-linked immunosorbent assay (ELISA) and gelatin-based zymography in skin fibroblasts. The extract of Juniperus chinensis showed strong inhibitory effect on MMP-1 activities by 97% at 100 ㎍/mL and suppressed the UVA induced expression of MMP-1 by 79% at 25 ㎍/mL. This extract also showed strong inhibition on MMP-2 activity in UVA irradiated fibroblast by zymography. We also examined anti-inflammatory effects by the determination test of proinflammatory cytokine, interleukin 6 in HaCaT keratinocytes. In this test Juniperus chinensis decreased expression of interleukin 6 about 30%. Expression of prostaglandin E₂, (PGE₂) after UVB irradiation was measured by competitive enzyme immunoassay (EIA) using PGE₂ monoclonal antibody. At the concentrations of 5-50 ㎍/mL of the extracts, the production of PGE₂ by HaCaT keratinocytes (24 hours after 10 mJ/cm² UVB irradiation) was significantly inhibited in culture supernatants (p〈0.05). The viability of cultured HaCaT keratinocytes was significantly reduced at the doses of above 10 mJ/cm² of UVB irradiation, but the presence of these extracts improved cell viability comparing to control after UVB irradiation. We also investigated the protective effect of this extract in sodium lauryl sulfate (SLS)-induced irritant skin reactions from 24 hour exposure. Twice a day application of the extract for reducing local inflammation in human skin was done. Irritant reactions were assessed by various aspects of skin condition, that is, erythema (skin color reflectance) and transepidermal water loss (TEWL). After 5 days the extract was found to reduce SLS-induced skin erythema and improve barrier regeneration when compared to untreated symmetrical test site. In conclusion, our results suggest that Juniperus chinensis can be effectively used for the prevention of UV and SLS-induced adverse skin reactions such as radical production, inflammation and skin cell damage.

Role of APS reductase in biogeochemical sulfur isotope fractionation

Min Sub Sim,Hideaki Ogata,Wolfgang Lubitz,Jess Adkins,Alex Sessions,Victoria Orphan,Shawn Mcglynn 대한지질학회 2018 대한지질학회 학술대회 Vol.2018 No.10

A Variation in non-skeletal carbonate mineralogy from the lower Paleozoic strata in Korea and South China

Min Sub Sim,Yong Il Lee 대한지질학회 2005 대한지질학회 학술대회 Vol.2005 No.

Equilibrium sulfur isotope fractionation during volatilization and deprotonation of H₂S

Min Sub Sim 대한지질학회 2017 대한지질학회 학술대회 Vol.2017 No.10

Quantification and isotopic analysis of intracellular sulfur metabolites in the dissimilatory sulfate reduction pathway

Min Sub Sim,Guillaume Paris,Jess F Adkins,Victoria J. Orphan,Alex L. Sessions 대한지질학회 2016 대한지질학회 학술대회 Vol.2016 No.10

Quantification and isotopic analysis of intracellular sulfur metabolites in the dissimilatory sulfate reduction pathway

Sim, Min Sub,Paris, Guillaume,Adkins, Jess F.,Orphan, Victoria J.,Sessions, Alex L. Pergamon Press 2017 Geochimica et cosmochimica acta Vol.206 No.-

<P><B>Abstract</B></P> <P>Microbial sulfate reduction exhibits a normal isotope effect, leaving unreacted sulfate enriched in <SUP>34</SUP>S and producing sulfide that is depleted in <SUP>34</SUP>S. However, the magnitude of sulfur isotope fractionation is quite variable. The resulting changes in sulfur isotope abundance have been used to trace microbial sulfate reduction in modern and ancient ecosystems, but the intracellular mechanism(s) underlying the wide range of fractionations remains unclear. Here we report the concentrations and isotopic ratios of sulfur metabolites in the dissimilatory sulfate reduction pathway of <I>Desulfovibrio alaskensis</I>. Intracellular sulfate and APS levels change depending on the growth phase, peaking at the end of exponential phase, while sulfite accumulates in the cell during stationary phase. During exponential growth, intracellular sulfate and APS are strongly enriched in <SUP>34</SUP>S. The fractionation between internal and external sulfate is up to 49‰, while at the same time that between external sulfate and sulfide is just a few permil. We interpret this pattern to indicate that enzymatic fractionations remain large but the net fractionation between sulfate and sulfide is muted by the closed-system limitation of intracellular sulfate. This ‘reservoir effect’ diminishes upon cessation of exponential phase growth, allowing the expression of larger net sulfur isotope fractionations. Thus, the relative rates of sulfate exchange across the membrane versus intracellular sulfate reduction should govern the overall (net) fractionation that is expressed. A strong reservoir effect due to vigorous sulfate reduction might be responsible for the well-established inverse correlation between sulfur isotope fractionation and the cell-specific rate of sulfate reduction, while at the same time intraspecies differences in sulfate uptake and/or exchange rates could account for the significant scatter in this relationship. Our approach, together with ongoing investigations of the kinetic isotope fractionation by key enzymes in the sulfate reduction pathway, should provide an empirical basis for a quantitative model relating the magnitude of microbial isotope fractionation to their environmental and physiological controls.</P>