GDI 엔진의 흡기계 정상상태 유동 특성에 관한 연구

李珉湖,尹俊圭,車京玉 明知大學校 産業技術硏究所 2004 産業技術硏究所論文集 Vol.23 No.-

Lean burn gasoline engine, classified into port injection and direct injection, is recognized as a promising way to meet better fuel economy. Especially, gasoline direct injection engine is becoming increasingly popular due to their potential for improved fuel economy and emissions. Also, GDI engine has the advantages of higher power output, higher thermal efficiency, higher EGR tolerance due to the operation characteristics of increased volumetric efficiency, compression ratio and ultra-lean combustion scheme. However, GDI engine has many difficulties to be solved, such as complexity of injection control mode(fuel injection timing, injection rate), fuel injection pressure, spark timing, unburned hydrocarbon and restricted power. This study aims to develope fundamental key techniques for the lean burn in GDI engine. The techniques in this study include intake port design (SCV) and test method. Experimental is applied to investigate the effects of swirl control valves to improve the engine performance and emission, efficiency in GDI engine.

서울의 Penicillinase Producing Neisseria Gonorrhoeae 발생빈도(1996)

김재홍,황동규,전재홍,김윤석,김중환,김용준,이창균,임동진,김현수,조창근,김경문,박상훈,전우형,김희성,이호정,차명수,김갑형,김형석,김석우,황지환,박병순,권오상,이민수,송기훈,성소영,이인섭,부태성 대한화학요법학회 1999 대한화학요법학회지 Vol.17 No.2

Background : In recent years, gonorrhea has been panedemic and remains one of the most commom STDs in the world, especially in developing countries. Objective & Methods: For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the VD Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results: In 1996, 139 strains of N. gonorrhoeae were isolated, among which 53(39.0%) were PPNG. Conclusion: Our results suggests that after a peak of 74.3% in 1993, the prevalence of PPNG in Seoul is gradually declining.

Optimization of Electric Field-assisted Ultrasonication for Disintegration of Waste Activated Sludge

( Kyung-won Jung ),( Tae-un Jeong ),( Min-jung Cha ),( Kyu-hong Ahn ) 한국폐기물자원순환학회(구 한국폐기물학회) 2014 한국폐기물자원순환학회 심포지움 Vol.2014 No.1

In the present study, an electric field is applied in order to disintegrate waste activated sludge (WAS). As a preliminary step, feasibility tests are investigated using different applied voltages of 10 to 100 V for 60 min. As the applied voltage increases, the disintegration degrees (DD) are gradually enhanced, thereby the soluble N, P, and carbohydrate concentrations increase simultaneously due to the protein decomposition. Subsequently, an optimization process is conducted using response surface methodology with a Box-Behnken design (BBD). The total solid concentration, applied voltage, and reaction time are selected as independent variables, while the DD is selected as the response variable. The overall results demonstrate that the BBD with an experimental design can be useed effectively in the optimization of the electric field treatment of WAS. In the confirmation test, a DD of 10.26±0.14% is recorded, which corresponds to 99.1% of the predicted response value under the statistically optimized conditions. Finally, the statistic optimization of the combined treatment (electric field + ultrasonication) showed that even though this is limited to highly disintegrated WAS when being applied individually, a high DD of 47.28±0.20% was recorded where the TS concentration was 6,780 mg/l, the strength of ultrasonication was 8.0 W, the applied voltage was 68.4 V, and the reaction time was 44 min. E-SEM images clearly revealed that the application of the electric field is a significant alternative method for the combined treatment of WAS, and this is first attempt to increase disintegration using electric field for combined treatment with ultrasonication.

인진쑥 배지에서 배양한 노루궁뎅이버섯 균사체 추출물(HEAC)의 알코올 대사촉진 활성

최원식(Choi, Won-Sik),장도연(Jang, Do-Yoen),차경민(Cha, Kyung-Min),박천규(Park, Chun-Kyu) 한국산학기술학회 2008 한국산학기술학회논문지 Vol.9 No.1

인진쑥 배지에서 배양한 노루궁뎅이버섯(HEAC), 노루궁뎅이버섯과 인진쑥 추출물들의 음주 후 체내 알코올 농도의 감소 효과를 확인하였으며, 또한 혈중 알코올 탈수소효소 및 아세트알데히드 탈수소효소의 활성을 조사하여 알코올 분해 활성을 조사하였다. 체내 알코올 농도 측정결과 HEAC의 경우 170분, 노루궁뎅이 버섯 추출물은 210 분후에 혈중 알코올이 검출되지 않았다. 또한, HEAC는 알코올 탈수소효소 활성에서 대조군 보다 시간에 따라 154%, 노루궁뎅이버섯 추출물은 148%로 비교적 높은 활성을 나타내었다. 아세트알데히드 탈수소활성에서는 HEAC와 노루궁뎅이버섯 추출붙이 대조구에 비해 104~111%이상의 효소활성이 유지되는 것을 확인하였으며 이들 추출물들은 알코올 분해 촉진작용이 매우 우수함을 알았다. Alcohol concentration in the blood was effectively decreased by extracts from Hericium erinaceum hypha cultivated with Artermisia capillaris medium(HEAC), Hericium erinaceum hypha and Artermisia capillaris after dirnking. Also, the activities of alcohol dehydrogenase and acetaldehyde dehydrogenase in the blood was studied. As a result of testing an alcohol concentration in the blood, the alcohol in the blood was not detected after 170 min. in case of HEAC and after 210 min. in case of Hericium erinaceum. Compared to control, each activities of alcohol dehydrogenase of HEAC and Hericium erinaceum hypha was showed up to 154% and 148% respectively. The activities of the acetaldehyde dehydrogenase of both extracts from HEAC and Hericium erinaceum was maintained in the range of 104 to 110% compared to control. In conclusion, such extracts represent significant effect to facilitate decomposition of alcohol.

Canola oil is an excellent vehicle for eliminating pesticide residues in aqueous ginseng extract

Cha, Kyu-Min,Lee, Eun-Sil,Kim, Il-Woung,Cho, Hyun-Ki,Ryu, Ji-Hoon,Kim, Si-Kwan The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.3

Background: We previously reported that two-phase partition chromatography between ginseng water extract and soybean oil efficiently eliminated pesticide residues. However, an undesirable odor and an unpalatable taste unique to soybean oil were two major disadvantages of the method. This study was carried out to find an alternative vegetable oil that is cost effective, labor effective, and efficient without leaving an undesirable taste and smell. Methods: We employed six vegetable oils that were available at a grocery store. A 1-mL sample of the corresponding oil containing a total of 32 pesticides, representing four categories, was mixed with 10% aqueous ginseng extract (20 mL) and equivalent vegetable oil (7 mL) in Falcon tubes. The final concentration of the pesticides in the mixture (28 mL) was adjusted to approximately 2 ppm. In addition, pesticides for spiking were clustered depending on the analytical equipment (GC/HPLC), detection mode (electron capture detector/nitrogen-phosphorus detector), or retention time used. Samples were harvested and subjected to quantitative analysis of the pesticides. Results: Soybean oil demonstrated the highest efficiency in partitioning pesticide residues in the ginseng extract to the oil phase. However, canola oil gave the best result in an organoleptic test due to the lack of undesirable odor and unpalatable taste. Furthermore, the qualitative and quantitative changes of ginsenosides evaluated by TLC and HPLC, respectively, revealed no notable change before or after canola oil treatment. Conclusion: We suggest that canola oil is an excellent vehicle with respect to its organoleptic property, cost-effectiveness and efficiency of eliminating pesticide residues in ginseng extract.

Korean red ginseng attenuates doxorubicin-induced testicular dysfunction in rats by modulating inflammatory, oxidative, and autophagy responses

Cha, Kyu-Min,Kopalli, Spandana Rajendra,Han, Sang Yun,Lee, Sang-Ho,Jeong, Min-Sik,Cho, Jae Youl,Han, Chang-Gyun,Lee, Seung-Ho,Kim, Soo-Nam,Kim, Jin-Chul,Kim, Si-Kwan Elsevier 2018 Journal of Functional Foods Vol.40 No.-

<P><B>Abstract</B></P> <P>The effect of Korean red ginseng (KRG; <I>Panax ginseng</I> Meyer) against doxorubicin (DOX)-induced testicular inflammation was investigated. Male Sprague-Dawley rats were treated with DOX (1 mg mL<SUP>−1</SUP> kg<SUP>−1</SUP> week<SUP>−1</SUP>; intra-peritoneally) for 8 weeks, and KRG water extract (EX1; 100 and EX2; 200 mg/kg/day; orally) was administered for 9 weeks starting one week before DOX exposure. The expression levels related to spermatogenesis, inflammatory and autophagy markers were evaluated using western blotting and reverse transcriptase polymerase chain reaction. DOX-induced a significant (<I>p</I> < .05) alteration in the expression of antioxidation spermatogenesis and sex hormone receptors genes when compared with control groups, which were attenuated with KRG-WE treatment significantly (<I>p</I> < .05 ∼ <I>p</I> < .01). KRG-WE also ameliorated the DOX-induced alteration in pro-inflammatory cytokines via the mitogen-activated protein kinases/nuclear factor kappa-B pathway and autophagy in the testes of rats. In conclusion, KRG might be used as a functional food for prevention of chemotherapy-induced testicular inflammation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> KRG attenuated mRNA expression of spermatogenesis in DOX-induced rat testis. </LI> <LI> KRG inhibited the DOX-induced inflammatory activation in rat testis. </LI> <LI> KRG ameliorated the changes in DOX-induced mTORC expression in rat testis. </LI> </UL> </P>

차상통합신호시스템에서 k out of n 시스템 적용에 대한 신뢰도 및 손실비용 분석에 관한 연구

김민규(Min-Kyu Kim),차기호(Gi-Ho Cha),김민석(Min-Seok Kim),이종우(Jong-Woo Lee) 한국철도학회 2012 한국철도학회논문집 Vol.15 No.1

자율주행자동차 상용화를 위한 법규제·개정 필요성 검토

차민규(Cha, Min-Kyu),조현빈(Jo, Hyun-Bin) 한국민간경비학회 2020 한국민간경비학회보 Vol.19 No.1

최근 제4차 산업혁명이 화두로 떠오르고 있으며 인공지능, 로봇공학, 사물인터넷, 나노기술 등이 대표적인 분야로 떠오르고 있다. 자율주행 자동차 또한 이러한 4차 산업혁명의 주요 분야로 얘기되고 있으며 2020년 상용화를 목적으로 하고 있다. 자율주행자동차는 운전자의 조작없이 자동차의 기능을 통해서 운행하는 차량을 말하는 것으로 이러한 새로운 개념의 차량이 도입되기 위해서는 미리 법과 제도를 통해 준비할 필요가 있다. 우리나라는 자율주행자동차 산업에 있어서 후발주자로 빠르게 선진국들을 따라잡아야 하는 입장이다. 해외 선진국에서는 이미 법·제도적으로 논의가 이루어지고 있으며 법률이 제·개정되고 있다. 국내에서도 법률 제·개정 움직임을 보이고 있고 국내 연구에서도 자율주행자동차와 차량중심으로 자동차관리법이나 사고의 법적 책임, 보험 등에 대해서 논의되고 있지만 더 다각적인 논의가 필요하다. 이를 위해서 자율주행자동차와 관계있는 여러 법과 제도들을 살펴볼 필요가 있고 이를 다각적으로 검토해야 한다. 이를 위해서 자율주행관련 법·제도를 규제적인 측면, 제조·허가 측면, 관리 측면, 운행 측면, 사고의 법적책임, 인프라 구축의 6가지 측면으로 살펴보았다. 규제적인 측면에서는 자율주행자동차의 시험운행이나 도로주행에 관해서 규제가 완화될 필요가 있고 제조나 허가 측면에서는 도로환경이나 날씨와 같은 운행환경에 따른 기능의 정의와 운행을 위한 기준이 정의될 필요가 있다. 그리고 관리적인 측면에서는 첨단기술이 적용된 자율주행자동차의 관리주체의 선정과 일반적인 차량보다 정기적인 검사빈도가 짧을 필요성이 얘기되었고 운행 측면에서는 일반차량과 같이 운행되기 위해서 기술적 측면의 완성과 자율주행차량 운전자 의무완화 등을 얘기하였다. 사고의 법적 책임에 있어서는 3단계까지는 운전자가 개입이 크기 때문에 현행 법제도가 적용될 수 있지만 이후 단계에서는 운전자나 탑승자보다는 제조사와 시스템설계사 등의 책임을 입증하는 것이 문제가 될 것으로 나타났다. 그리고 인프라 측면에서는 효율적이고 안전한 운행을 위해서는 도로정보의 디지털 인프라 구축과 정보통신망의 연계가 중요한 것으로 얘기되었다. 2020년 올해 자율주행자동차의 상용화를 목전에 두고 있기 때문에 법·제도적인 준비는 반드시 필요하다. 또한 후발주자로서 다른 선진국들을 추격하고 안정적인 국내도입을 위해서도 법률과 제도의 다각적인 검토가 있어야 한다. 앞서 얘기한 법·제도들 외에도 자율주행자동차의 상용화와 관련된 법률들은 더 많을 것이기 때문에 이후에도 지속적이고 추가적인 연구가 이어져야 할 것이다. The fourth industrial revolution has recently emerged as a hot topic, with artificial intelligence, robotics, the Internet of Things and nanotechnology emerging as major areas. Autonomous vehicles are also said to be a major area of this fourth industrial revolution and are aimed at commercializing them in 2020. Autonomous vehicles are a new concept of vehicles that operate through the functions of a car without the driver s control. In order for these new concepts to be introduced, it is necessary to prepare them through laws and institutions in advance. The nation needs to quickly catch up with advanced countries as a latecomer in the Autonomous car industry. However, it needs to be discussed more actively both technically and legally. In advanced countries, legal and institutional discussions are already taking place, and laws are being enacted and revised. Although domestic research is still discussing areas directly related to Autonomous vehicles and vehicle centers, legal responsibilities for accidents and insurance, more diverse discussions are needed. To this end, various laws and systems related to Autonomous vehicles need to be looked at and examined in various ways. To this end, we looked at the regulatory aspects, the manufacturing and licensing aspects, the management aspects, the operation aspects, the legal responsibilities of accidents, and the construction of infrastructure. On the regulatory side, regulations need to be eased regarding the test operation or road driving of Autonomous vehicles, and on the manufacturing or approval side, the definition of functions and standards for operation according to the driving environment, such as road environment and weather, need to be stipulated. And in terms of management, it was said that management bodies or regular inspections of Autonomous vehicles with high-tech features were needed, and in terms of operation, technical aspects were completed in order to operate like normal vehicles, and drivers of Autonomous vehicles were relieved. In terms of legal responsibility for the accident, the current legal system can be applied up to the third stage, but it has been revealed that the subsequent stage will be a problem to prove the responsibility of manufacturers and system designers rather than drivers or passengers. In terms of infrastructure, it was said that the digital infrastructure of road information and the linkage of information and communication networks were important for efficient and safe operation. Legal and institutional preparations are essential as the country is about to commercialize Autonomous vehicles this year. In addition, it is necessary to pursue other advanced countries as a latecomer and to conduct a stable domestic acquisition.

Pectinase-treated <i>Panax ginseng</i> protects heat stress-induced testicular damage in rats

Kim, Min Kyoung,Cha, Kyu-Min,Hwang, Seock-Yeon,Park, Un-Kyu,Seo, Seok Kyo,Lee, Sang-Ho,Jeong, Min-Sik,Cho, SiHyun,Kopalli, Spandana Rajendra,Kim, Si-Kwan BioScientifica Ltd 2017 Reproduction Vol.153 No.6

<P>Testicular hyperthermia is well studied to cause impaired spermatogenesis. In the present study, the protective effect of enzymatically modified (pectinase-treated) Panax ginseng (GINST) against intermittent sub-chronic heat stress-induced testicular damage in rats was investigated. Male Sprague-Dawley rats were divided into four groups: normal control (NC), heat-stressed control (HC), heat- stressed plus GINST-100mg/kg/day (HG100) and heat- stressed plus GINST-200mg/kg/day (HG200) treatment groups. GINST (100 and 200mg/kg/day) was mixed separately with a regular pellet diet and was administered orally for 8 weeks starting from 1 week before heat exposure. Parameters such as organ weight, blood chemistry, sperm kinetic values, expression of antioxidant enzymes, spermatogenesis molecules and sex hormone receptors levels were measured. Data revealed that kidney and epididymis weight were significantly (P < 0.05) decreased with heat stress and recovered by GINST treatment. Further, the altered levels of blood chemistry panels and sperm kinetic values in heat stress-induced rats were attenuated when GINST was administered (P < 0.05). Furthermore, the expression levels of antioxidant-related enzymes (GSTM5 and GPX4), spermatogenesis-related proteins (CREB1 and INHA) and sex hormone receptors (androgen receptor, luteinizing hormone receptor and follicle-stimulating hormone receptor) were reduced by heat stress; however, GINST treatment effectively ameliorated these changes. In conclusion, GINST was effective in reducing heat-induced damage in various male fertility factors in vivo and has considerable potential to be developed as a useful supplement in improving male fertility.</P>

강우 시 입자상 물질 변화에 따른 비점오염물질 분포 변화

차성민 ( Sung Min Cha ),강주현 ( Joo Hyon Kang ),이승원 ( Seung Won Lee ),김희준 ( Hee Jun Kim ),박민규 ( Min Kyu Park ),김승준 ( Seung Joon Kim ),김준하 ( Joon Ha Kim ) 한국물환경학회 2010 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2010 No.-