메탄/공기 층류 부분예혼합화염의 상세 라디칼(OH*, CH* 그리고 C₂*) 정보와 배기매출물에 관한 실험적 연구

정용기,오정석,전충환,장영준,Jeong Yong Ki,Oh Jeong Seog,Jeon Chung Hwan,Chang Young June 대한기계학회 2005 大韓機械學會論文集B Vol.29 No.2

An experimental study was performed to investigate the effects of partially premixing, varying the equivalence ratios from $0.79{\sim}{\infty}$, on NOx emissions and chemiluminescence of excited $OH^{\ast},\;CH^{ast}\;C_2^{\ast}$ radicals in laminar partially premixed flames. the signal from the electronically excited state of $OH^{\ast},\;CH^{ast}\;C_2^{\ast}$ was detected through a band pass filter with a photo multiplier tube, which are processed to the intensity ratio ($C_2^{\ast}/CH^{\ast},\;C_2^{\ast}/OH^{\ast},\;and\;CH^{\ast}/OH^{\ast}$) to reveal the correlation with local equivalence ratio. And measurements of NOx emission were made to investigate the relationship between visible flame appearance, chemiluminescence, and EINOX. The results demonstrated that (1) the flames at ${\phi}<1.59$ exhibited classical double flame structure, at ${\phi}>4.76$, the flames exhibited diffusion flame structure, and the intermediate flames at $1.59<{\phi}<4.76$ was a merged flame, (2) the $OH^{\ast}$ peak was located inside the $CH^{\ast}\;and\;C_2^{\ast}$ radical for all measured conditions and the emission intensity ratio of $C_2^{\ast}/CH^{\ast}\;and\;C_2^{\ast}/OH^{\ast}$ were identified as good marker for local equivalence ratio over a range of ${\phi}=0.79{\sim}1.2\;and\;CH^{\ast}/OH^{\ast}\;is\;0.79<{\phi}<1.9$. However, it was difficult to predict the equivalence ratio in partially premixed flames using this system for ${\phi}>2.38$, (3) the minimum NOX emission index (EINOx) is obtained for a equivalence ratio of 3.19 in the intermediate flames.

비만증 환자에서 한약제에 의한 체중 감소효과

Oh, Seung-Joon,Jeong, In-Kyung,Kim, Young-Seol,Choi, Young-Kil,Paeng, Jeong-Ryung,Bae, Jung-Hwan,Shin, Hyun-Dae 경희대학교 동서의학연구소 1999 INTERNATIONAL SYMPOSIUM ON EAST-WEST MEDICINE Vol.1999 No.1

Seung-Joon Oh, In-Kyung Jeong, Young-Seol Kim, Young-Kil Choi, Jeong-Ryung Paeng¹, Jung-Hwan Bae and Hyun-Dae Shin²Department of internal Medicine, College Medicine, Endocrine Research Institute¹. Department of Rehabilitation, College of Oriental Medicine², Seoul, korea. Bady Fat Reduction Effects of Red Ginseng Compound Preparation on the Patients with Obesity. Proceedings of International Symposium on East-West Medicine, Seoul. 244-254, 1999.-Obesity can be defined as a metabolic disease due to an increased state of fat tissues caused by an imbalance of calorie intake and use. Recently, in Korea by improvement and westernization of food intake, along with decrease in exercise activities, the prevalence of obesity has increased greatly. Our objectives were to study stability and effects of decrease in body fat by administering red ginseng compound preparation (known to have body fat decreasing effects in laboratory animals) to obesity patients on low calorie diets. Changes in weight and body fat were measured while carrying out calorie-restricted diets on patients for 4 weeks, then administering red ginseng compound preparation for another 4 weeks. The patients were 20 people whose BMI were 25kg/㎡ or over and whose percent body fat was also 30% or over when tested by bioelectrical conductivity. 1. Changes in weight were from 70.04kg(base line) to 67.43kg(after taking red ginseng compound preparation). 2. In similar sense, BMI decreased from 27.12kg/㎡(base line) to 26.56kg/㎡(after dieting), and further to 26.01kg/㎡ (after taking red ginseng compound preparation). The BMI seemed to decrease significantly compared to the baseline after the use of red ginseng compound. 3. Waist hip ratio was changed from 0.8858(base line) to 0.8728, but it was statistically insignificant. 4. The percent body fat was 35,16%(base line), 33.87%(after dieting), and 31.68%(after taking red ginseng compound preparation). 5. Complete blood cell count and blood chemisrty remained unaffected by the administration. 6. In concern to endocrinologic studies, T3 decreased from 118.7 to 98.2ng/dL, and T4 increased from 8.8 to 9.2㎕/ dL. Epinephrine showed a tendency to decreased from 0.27 to 0.25 ng/mL, and norepinephrine increased from 0.39 to 0.44ng/mL. 7. Leptin was not changed. 8. Some patients complained adverse effects; constipation(5 patients, may be due to diet therapy), fatigue (2 patients), pruritus(2 patients), flushing(s patients), dizziness(3 patients) and epigastric discomfort(2 patients). However their symptoms were mild, so medication did not stopped. In conclusion, loss of weight without significant side effects was observed during low calorie diet and red ginseng compound preparation administration. This is thought to be in relation to sympathetic nerve system rather than adrenal gland. Also, further long0term studies should be required, since the observed results were based on short-term changes in weight.

Protective Effects of Portulaca oleracea L. Extract against Matrix Metalloproteinase Production and Reactive Oxygen Species Generation Induced by Ultraviolet B Radiation in Human Keratinocytes

Jung Hwan Oh(오정환),Fatih Karadeniz(파티 카라데니즈),Jung Im Lee(이정임),So Young Park(박소영),Youngwan Seo(서영완),Chang-Suk Kong(공창숙) 한국생명과학회 2018 생명과학회지 Vol.28 No.8

쇠비름(Portulaca oleracea.L)은 쇠비름과에 속하는 한해살이풀로서 리놀렌산과 같은 불포화지방산, 페놀성 화합물, 플라보노이드, 비타민 C, 미네랄 함량이 높은 것으로 보고되어 있다. 본 연구에서는 쇠비름 추출물을 이용하여 UVB를 조사한 인간각질형성세포에서 광노화 억제능을 확인하였다. Matrix metalloproteinases는 세포의 기질을 분해하는 효소로 MMP-1는 collagenase, MMP-2와 MMP-9는 gelatinases로 피부 진피층을 구성하는 type Ⅰ collagen을 분해시키는데 영향을 미친다. UVB를 조사한 인간각질형성세포에서 쇠비름 추출물을 처리했을 때 MMP-1, -2, -9의 발현이 감소하였으며, type Ⅰ procollagen의 발현은 증가하는 것으로 나타났다. 또한 쇠비름 추출물을 처리한 군에서 UV에 의한 ROS 생성이 감소하였는데 이는 Nrf-2의 활성화를 통한 항산화 인자 SOD-1과 OH-1의 발현 증가로 인해 세포내 ROS 생성이 감소한 것으로 사료된다. 따라서 본 연구 결과를 통해 쇠비름 추출물이 UVB를 조사한 인간각질형성세포에서 MMP 인자 및 항산화 인자의 발현 조절을 통해 광노화로부터의 세포 보호능을 가지는 것을 확인하였으며 나아가 화장품 소재로서의 개발 가능성을 확인하였다. Portulaca oleracea L. is an edible plant widely consumed in daily diet throughout Europe, Asia and America. In this study, protective effects of P. oleracea L. extracts against oxidative stress and matrix metalloproteinase (MMP) activity induced by ultraviolet B (UVB) radiation were investigated using HaCaT immortal human keratinocytes. In this context, the mRNA and protein productions of MMPs (MMP-1, -2, and -9) and type I procollagen, which are major markers of photoaging induced by UVB radiation in HaCaT keratinocytes, were evaluated. Furthermore, UVB-induced reactive oxygen species (ROS) generation and mRNA and protein expression levels of superoxide dismutase-1 (SOD-1), oxygenase-1 (OH-1), and nuclear factor-erythroid 2-related factor-2 (Nrf-2), all of which are associated with the antioxidant balance, were investigated. As shown by the results, UVB radiation induced ROS formation and led to increased production of MMPs and decreased collagen production in human keratinocytes, which resulted in skin photoaging or photodamage. The treatment with P. oleracea L. extracts downregulated MMP (MMP-1, -2, and -9) production and upregulated type I procollagen expression in UVB-induced HaCaT cells. Furthermore, treatment with the extracts decreased UVB-induced ROS generation and increased the expression of antioxidant enzymes, such as SOD-1 and OH-1, through the Nrf-2 pathway. Taken together, these results suggest that P. oleracea L. extracts could be a potential cosmeceutical agent for the prevention of skin photoaging or photodamage.

공공기술 기반 여성기술창업에 관한 탐색적 연구: 여성연구소기업을 중심으로

오영환(Oh, Young-Hwan),정양헌(Chung, Yang-Hon) 한국경영교육학회 2021 경영교육연구 Vol.36 No.4

[연구목적] 본 연구에서는 여성기술창업에 대한 연구가 미흡한 시점에서 공공기술을 기반으로 설립되는 여성연구소기업의 창업가에 대한 인터뷰를 통해 창업 동기, 목적, 창업아이템 선정, 사업화 과정, 특성 등을 파악하여 연구소기업이 여성기술창업 지원제도로서 적합한가와 여성기술창업의 활성화방안을 살펴보고 시사점을 제공하고자 하였다. [연구방법] 본 연구는 질적 연구방법론인 근거이론에 대한 이론들과 기존에 수행되었던 여성기술창업, 연구소기업 등의 연구들을 충분히 검토하고, 8명의 연구소기업의 여성창업가를 대상으로 인터뷰를 진행하였다. 근거이론의 탐색적 접근방법을 통해 인터뷰 내용을 개방코딩, 축 코딩, 선택코딩 등으로 분석하여 여성기술창업의 특성을 확인해 보았다. [연구결과] 연구결과로 공공기술을 기반으로 설립된 연구소기업은 연구개발특구의 설립지원, 기술사업화 과제, 성장 지원 등과 대학 및 연구원의 기술지원 등으로 유익한 여성기술창업지원 제도이다. 따라서 주도적 개인 성향과 기술 기반의 창업역량을 보유한 예비 여성창업가를 적극 발굴하여 여성연구소기업을 더욱더 확대해야 한다. [연구의 시사점] 본 연구는 여성기술창업의 활성화를 위해 여성 친화적 기술 및 제품과 연계된 기술창업지원 프로그램 확대, 여성연구소기업에 대한 지원 확대 및 우대, 창업기업의 기술사업화를 위한 기술지원과 사업화 프로그램 강화, 여성창업가의 일과 가정의 양립으로 인한 어려움을 해소할 수 있는 인력지원 등이 확대되어야 한다는 시사점을 제공한다. [Purpose] In this study, we interviewed women CEO in Research Institute Companies established to identify their startup motivations, the purpose of a startup, the selection of startup items, the commercialization process, and the characteristics of women-led technology startups to provide implications and examine whether a Research Institute Spin-off Company is suitable and expandable as a women-led technology startup support system. [Methodology] This study conducted interviews with 8 women CEO of Research Institute Spin-off Companies. Through the grounded theory, the interview contents were analyzed to identify the characteristics of women-led startups. [Findings] As a result of research, it is show that a Research Institute Spin-off Company established based on public technology is a beneficial women-led technology startup support system, having the support from the INNOPOLIS, technology commercialization projects, various growth supports, and technical support from universities and research institutes. It is suggested that women-led Research Institute Spin-off Companies should be further expanded by actively discovering prospective women entrepreneurs that have a personal tendency of playing a leading role and entrepreneurship capable of building a technology startup. [Implications] This study suggests that in order to revitalize women-led technology startups, there needs to be an expansion of technology startup support programs connected to women-friendly technologies and products, expanded support and preference towards women-led Research Institute Spin-off Companies, expansion of technology and commercialization support to resolve the difficulties of technology commercialization, and personnel support to relieve the work-family balance of women entrepreneurs.

메탄 공기 층류 부분 예혼합화염에서 예혼합 정도에 따른 화염구조와 질소산화물의 배출에 미치는 영향에 관한 연구

오정석(Jeong Seog Oh),정용기(Yong Ki Jeong),전층환(Chung Hwan Jeon),장영준(Young June Chang) 대한기계학회 2003 대한기계학회 춘추학술대회 Vol.2003 No.11

It is shown that the effect of variable parameters on flame structures and NOx emissions in the laminar<br/> partially premixed methane-air flames with a co-axial Bunsen burner. Objectives of this paper is to<br/> understand the effects of flow variables on NOx emissions and the flame structure with OH<br/> chemiluminescence, including reconstructed image by abel inversion processing at each conditions. A fuel<br/> flowrate of 200 [cc/min] was fixed and the amount of air was varied from 400 to 1200 [cc/min]. The<br/> experimental variables were equivalence ratio( ), fuel split percentage( ) and inner tube recess(x/D). Flow<br/> conditions were ranged from 1.36~4.76(equivalence ratio), 50~100(fuel split percentage) and 0~20(inner<br/> tube recess). NOx analyzer and ICCD camera with a OH filter were used as a main experimental<br/> apparatus. In addition, Abel inversion, which is a kind of tomography and valuable to estimate a<br/> two-dimensional structure of co-axial flames from cubical information, was employed for combustion<br/> diagnostics. Results from this study indicate that the main effects depend on equivalence ratio and next<br/> sigma, x/D for NOx production and OH formation. Throughout Abel inversion, we could affirm the<br/> maximum position and the tendency of OH radical intensity by variants at five axial heights above the<br/> burner exit.

정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

歸納的 推論과 直觀의 問題

吳榮煥 연세대학교 대학원 1978 延世論叢 Vol.15 No.1

How do scientists' minds work as they try by observation, experiment, and reflection to solve the problem set for them by Nature? Is there an established method of scientific thinking? Few scientists have attempted to analyze their own thought processes. They get on with their work and arrive at their conclusions without deeply considering the mental pathways they followed. Working scientists have generally regarded with indifference the attempt of philosophers to categorize the steps of scientific thought, for example, sharply contrasting "deduction" and "induction", for they do not recognize these processes as distinguishable in their work. Thus the subject matter began in the present writer's mind in the form of a question: why are most scientists completely indifferent to -even contemptuous of -scientific methodology? Put generally, the answer could only be "because what pasties for scientific methodology is a misrepresentation of what scientist do or ought to do." The writer therefore thought it important to explain what is wrong with the traditional methodology of "inductive" reasoning, as the writer sees it, and to show that the alternative scheme of reasoning associated with the names of Popper and Medawar can give the scientist a certain limited but useful insight into the war he thinks.

β-glycerophosphate 혼합시 인간 치수 세포에 대한 Portland cement의 생활성에 관한 연구

오영환,장영주,조용범 대한치과보존학회 2009 Restorative Dentistry & Endodontics Vol.34 No.5

β-glycerophosphate는 치수의 상아모세포 분화를 촉진하는 물질이다. Portland cement는 수중에서 장기간에 걸쳐 용해되기 때문에 β-glycerophosphate을 혼합한 Portland cement는 수산화칼슘과 함께 β-glycerophosphate를 장기간 용출하게 된다. 본 실험에서는 β-glycerophosphate을 혼합한 Portland cament에 대한 인간치수세포의 반응을 알아보았다. 인간 치수 세포에 대한 β-glycerophosphate의 효과를 알아보기 위해 다양한 농도의 β-glycerophosphate와 dexamethasone에 대한 인간 치수 세포의 ALP activity을 측정하였고 alizarin red S로 염색하여 관찰하였다. β-glycerophosphate가 다양한 농도(10 mM, 100 mM, 1 M)로 혼합된 Portland cement에 대한 인간 치수 세포의 MTS assay, ALP activity를 측정하고 SEM으로 관찰하였다. 치수세포의 석회화 정도를 관찰한 연구에서 β-glycerophosphate와 dexamethasone 단독으로 적용하였을 때 거의 효과가 없었으나 5 mM β-glycerophosphate와 100 nM dexamethasone을 혼합 적용하였을 때 가장 높은 ALP acticity를 보였다. 분화제를 첨가하거나 첨가하지 않은 모든 실험군에서 치수세포에 대한 독성은 관찰되지 않았으며 Portland cement에 10 mM β-glycerophosphate을 혼합한 시편의 ALP activity가 대조군에 비교하여 가장 많이 증가하였다. 결론적으로 β-glycerophosphate이 혼합된 Portland cement는 세포 독성이 없으며 첨가물이 없는 Portland cement에 비해 치수 분화 및 석회화를 더 많이 일으키므로 임상적으로 β-glycerophosphate을 혼합한 Portland cement 적용은 재료 하방에 더 많은 상아질을 형성시킬 것으로 추측된다. The purpose of this study is to investigate the response of human pulp cell on Portland cement mixed with β-glycerophosphate. To investigate the effect of β-glycerophosphate and/or dexamethasone on human pulp cell, ALP activity on various concentration of β-glycerophosphate and dexamethasone was measured and mineral nodule of human pulp cell was stained with Alizarin red S. MTS assay and ALP activity of human pulp cell on Portland cement mixed with various concentration of β-glycerophosphate (10 mM, 100mM, 1M) was measured and the specimens were examined under SEM. Addition of β-glycerophosphate or dexamethasone alone had no effect however, the addition of 5 mM β-glycerophosphate and 100 nM dexamethasone had the largest increasement in ALP activity. There was no toxicity in all samples and the data showed that Portland cement mixed with 10 mM β-glycerophosphate had more increase in ALP activity compared with control. In conclusion, Portland cement mixed with β-glycerophosphate has no toxicity and promotes differentiation and mineralization of pulp cell compared with additive-free Portland cement. This implicated that application of Portland cement mixed with β-glycerophosphate might form more reparative dentin and in turn it would bring direct pulp capping to success.

현대문화의 기능적 성격과 인간의 책임

오영환 연세대학교 대학원 1982 延世論叢 Vol.19 No.1

Divergent cultures are encountering each other more than ever. Every culture, moreover, is going through a process of acceleration and of changing values. These two aspects of our contemporary, growing world-culture motivate a new reflection on culture as such. We know, hotter than some decades ago, that culture is not only a piece of tradition, not only a gift, but also a perspective to be renewed, a task. Such a reflection has to be philosophical and practical at the same time. This paper does not present a description, much less an explanation, of the enormous cultural shift through which mankind today is going. The purpose of this paper is more limited: a simplified representation of the development of culture, a schema that may be useful in the changing situations we ourselves experience. The schematic approach has been elaborated in a model comprising three stages in the development of culture: where man is still part and parcel of the world around him; the ontological, where he acquires a more aloof attitude towards the surrounding world and towards himself; the functional, where he acquires insight into relations and so attempts to assess traditional data in a new way. In these three stages it is not a matter of ascending to higher level. No, each phase has its positive and its negative tendencies. That is why one should not go 'romancing' after a pattern of culture long past; nor yet should one take only a 'utopian' view, looking forward to a not yet existent of society. Culture is as wide as the realms of human life, reaching from agricultural to religion, from craftsmanship to social responsibility, from old tradition to creative renewal. Thus the main thesis of this paper is that'culture'is not a noun, a thing, but a verb, or in other words, 'culture' is of our own making, is our own responsibility. So our account of culture is a 'functional' one, relating it to our own policy of life. This means that cultural development does not take place above and beyond us. but that man himself must find a strategy of culture.

유방의 관상피내암종에서의 p27_kip1, Cyclin D1 및 p53 단백의 발현

오영륜,송상용,최종순,고영혜,이회정,안긍환 대한병리학회 1999 Journal of Pathology and Translational Medicine Vol.33 No.9