800㎿급 발전소 복수기의 최적 운전점 및 운전방법에 대한 연구

장철호(Cheol-Ho Jang),홍은기(Eun-Kee Hong),황광원(Kwang-Won Hwang),윤린(Rin Yun) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.5

Along with the recent construction of a 800㎿ thermal power plant it is necessary to check the soundness of the current operation of the condenser, and to investigate the effects of vacuum level of it on the turbine efficiency for the power plant. In this study, the performances of the condenser and the turbine for the 800㎿ thermal power plant were tested based on the ASME PTC 6 and ASME PTC 12.2 with the variation of the vacuum level. When the condenser vacuum levels were 719.91 ㎜Hg, 724.5 ㎜Hg, and 729.6 ㎜Hg, the turbine efficiencies were 47.36%, 47.47%, and 47.55%, respectively. From the regression analysis of the present data, it was estimated that the optimal vacuum point is between 729 ㎜Hg and 731 ㎜Hg. When this optimal point is to be applied to the condenser, the profit of 5.5 billion won/year is expected based on the '09 caloric cost.

The Antioxidant Effect of the Rhaponticum uniflorum Extracts on the Oxidative Stress in H₂O₂ induced Human Keratinocytes

So Hee Ahn,Won Yeoung Choi,Ji Won Jeong,Geon Woo Park,Su Yeon Kang,Eun Jeong Kim,Su Rim Sin,Eun Seo Jang,Gye Won Lee,Young Ho Cho 한국식품영양과학회 2021 한국식품영양과학회 학술대회발표집 Vol.2021 No.10

In this study, To investigate the antioxidant activities of Rhaponticum uniflorum extracts (RUE), we assessed scavenging activities on DPPH, ABTS radicals, and reducing power. The DPPH and ABTS radical scavenging activities (SC50) of RUE were 96.97±1.19 μg/mL and 31.26±0.13 μ g/mL, respectively, and the reducing power significantly increased dose-dependent manner. To study the antioxidant effecters of RUE in H₂O₂ induced human keratinocytes, expression of Nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were determined by Western blot and qRT-PCR. RUE induced the expression of HO-1, a critical target enzyme of Nrf2, in a concentration-dependent manner. The expression of HO- 1 mRNA was also induced in H₂O₂-treated HaCaT cells but no significant difference in the level of HO-1 mRNA was observed. Taken together, these results suggest that RUE may be useful as a potential ingredient for anti-aging products.

ATM과 멀티미디어를 이용한 원격 교육 시스템

장원호,박인호,류시국,강현석 慶尙大學校 1996 論文集 Vol.35 No.2

Recently, student-oriented education paradigms are appeared. At this point, we expect that the future's education will be changed by the distance eduation system based on multimedia materials. This study decribes an integerated real-time multimedia distance eduation system that uses ATM technology, object-relational detabase management system, and multimedia authoring tools to use interactive multimedia materials among remote sites in real-time.

구강에서 채취한 혐기성 세균에 대한 서양산 고추냉이(Horseradish, Armoracia rusticana) 뿌리 추출물의 항균효과

장용걸,박호원,신일식,이주현,서현우 大韓小兒齒科學會 2010 大韓小兒齒科學會誌 Vol.37 No.2

서양산 고추냉이 (Horseradish, Armoracia rusticana)의 주성분인 allylisothiocyanate(AIT)는 각종 세균에 대한 살균 효과로 주목받고 있다. 이전 연구들을 통해 구강내 다양한 세균 및 진균류에 대한 항균성이 입증되었으나 근단내 병소를 유발하는 혐기성 세균에 대한 연구는 미진한 실정이다. 본 연구에서는 사람의 근단 병소에서 직접 분리한 E. faecalis와 F. nucleatum에 대한 서양산 고추냉이 뿌리 추출물의 항균활성을 표준균주와 비교해보고 이를 대표적인 항균제인 클로르헥시딘과 비교하여 다음과 같은 결론을 얻었다. 1. 서양산 고추냉이 뿌리 추출물은 E. faecalis 임상 분리균주에 대하여 표준균주와 같거나 약간 높은 농도에서 항균효과를 나타냈고, 625.0~1,250.0 μg/ml의 농도에서 클로르헥시딘 (7.8~15.6 μg/ml)과 대등한 항균효과를 가지는 것으로 나타났다. 2. 서양산 고추냉이 뿌리 추출물은 F. nucleatum 임상 분리균주에 대하여 표준균주와 같거나 약간 높은 농도에서 항균효과를 나타냈고, 78.1~312.5 μg/ml의 농도에서 클로르헥사딘 (7.8~15.6 μg/ml)과 대등한 항균효과를 가지는 것으로 나타났다. 이번 연구로 표준균주 뿐만 아니라 구강에서 직접 분리한 혐기성 세균에 대한 서양산 고추냉이 뿌리 추출물의 항균성을 확인할 수 있었고, 추후 근관 세척제나 소독제로 서양산 고추냉이 뿌리 추출물을 이용할 수 있는 가능성을 보여주었다. Objective : The aim of this study was to determine the antimicrobical effect of horseradish root extracts against Enterococcus faecalis and Fusobacterium nucleatum isolated from oral cavity compared with reference strain, and compared with that of chlorhexidine. Method : Horseradish root extracts and chlorhexidine were sequentially diluted and tested against anaerobes(E. faecalis, F. nucleatum) isolated from children's oral cavity. The microbes were anaerobically incubated and the minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) were detected. Results: 1. Horseradish root extracts showed antimicrobial effect against E. faecalis isolated strain at same or slightly higher concentration compared with MIC of reference strain. 2. 625.0~1.250.0 ㎍/ml horseradish root extracts showed similar antimicrobial effect with chlorhexidine(7.8~15.6 ㎍/ml). 3. Horseradish root extracts showed antimicrobial effect against F. nucleatum isolated strain at same or slightly higher concentration compared with MIC of reference strain. 4. 78.1~312.5 ㎍/ml horseradish root extracts showed similar antimicrobial effect with chlorhexidine(7.8~15.6 ㎍/ml). Conclusions : The results of this study confirm that horseradish root extracts has antimicrobial effect against anaerobes isolated from oral cavity as well as reference strain. And we found the potential of horseradish root extracts as a canal irrigant or disinfectant.

ETACS와 CDMA 디지털 셀룰라 시스템이 공존하는 환경에서 Interference Canceller System의 설계 및 구현

장원호,홍주석,이윤현 한국항행학회 2002 韓國航行學會論文誌 Vol.6 No.4

본 논문에서는 인접한 대역에 ETACS와 CDMA 방식의 디지털 셀룰라 시스템이 공존하는 중국 상해 지역의 간섭환경에서 기존의 간섭제거장비보다 이를 효과적으로 개선할 수 있는 Interference Canceller Systern(ICS)을 설계하고, 개발된 부품들을 통해 구현하였다. 구현된 ICS는 무선 채널환경의 변화에 안정적이면서 인접한 대역의 ETACS와 CDMA방식의 디지털 셀룰라 시스템 간에 약 29dB이상의 간섭 제거 성능을 보유한 시스템임을 확인하였다. In this paper, we provide the Interference Canceller Systems(ICS) in the wireless environments in the presence of co-existing ETACS and CDMA digital cellular systems to effectively cancel the interference than the established canceller systems. We proved the enhanced cancelling performances more than 29 dB cancellation characteristics between co-existing ETACS and CDMA digital cellular systems and the stabilized system characteristics in the rapidly changing wireless circumstances.

Sophora flavescens의 뿌리에서 유래한 Cholinesterase 저해 화합물

장원희, 트란홍광, 김장훈, 양서영, 김영호 충남대학교 약학대학 의약품개발연구소 2021 藥學論文集 Vol.36 No.-

Searching for cholinesterase inhibitory compounds from natural products is important to de- velop therapeutic agents for Alzheimer’s disease. Our previous research on the chemical components of Sophora flavescens roots resulted in the isolation of twelve flavonoids, kushenol E (1), maackiain (2), 8-prenylkaemperol (3), 8-prenylnaringenin (4), kushenol L (5), kushenol A (6), kushenol C (7), kushenol B (8), sophoraflavanone G (9), kushenol H (10), isoxanthohumol (11) and kurarinone (12) and their structures were elucidated by spectroscopic methods. Inhibitory effect of cholinesterase were tested using the Ellman's method. Most flavonoid compounds showed good inhibitory activities on cholinesterases. Kushenol E (1) and sophoraflavanone G (9) showed good inhibitory activities on acetylcholinesterase with IC50 values of 3.75 and 4.14 μM and butyrylcholinesterase with IC50 values of 2.00 and 0.75 μM, respectively. In addition, a kinetic analysis revealed that kushenol E (1) was non-competitive inhibitor with Ki value of 0.77 μM on acetylcholinesterase and 0.16 μM on butyrylcholinesterase, whereas sophoraflavanone G (9) was mixed type inhibitior with Ki value of 9.42 μM on acetylcholinesterase and 0.81 μM on butyrylcholinesterase. These findings suggest that flavonoid compounds from S. flavescens roots are potential cholinesterase inhibitors.

四鹽化炭素로 肝障害를 誘導한 家兎에서의 抗結核劑의 排泄에 關한 硏究

元章喜,權昌鎬 慶熙大學校 1984 論文集 Vol.13 No.-

The drug metabolism of several antituberculosis was investigated in liver injuried rabbits. Antituberculosis drugs which used on this experiment were Rifampicin, Isoniazide and Pyrazinamide. The results were as follows. 1. Activities of sGOT and sGPT of rabbits induced liver injury by CCl_4 were increased (in sGOT, from 48.9 ± 1.48 units/ml to 370 ± 19 units/ml and in sGPT, from 42.5 ± 1.22 units/ml to 386 ± 32 units/ml) after the lapse of 24 hours from CCl_4 administration and then they were decreased gradually with the lapse of time (in sGOT, to 310 ± 25 units/ml and in sGPT, to 285 ± 26 units/ml after the lapse of 72 hours from CCl_4 administration). 2. The rifampicin which cxcreted mainly through bile at a small dose administration was excreted in urine at a large dose administration. 3. Each antituberculosis drugs which administrated on this experiment was excreted more quantity in urine of CCl_4 pretreated rabbits as compared with normal rabbits. particularly, Rifampicin was excreted far more quantity in urine of CCl_4 pretreated rabbits all the time. 4. From the above results, it was recognized that many notice about use of Antituberculosis drugs to liver injuried body must be required.

Bone-supported pendulum을 이용한 상악대구치 원심이동

장용걸,박호원,이주현,서현우 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.3

상악 대구치의 원심이동이 요구되는 경우, 구외견인, Wilson distalizing arches, 가철식 스프링 장치 그리고 Schwarz plate-type 장치 등을 사용 할 수 있다. 그러나 이러한 전통적인 대구치의 원심이동 장치들로 치료에 성공하기 위해서는 환자의 협조가 필수적이기 때문에 많은 소아치과 의사들은 환자 의존성을 최소화하고 임상가가 통제 할 수 있는 장치들로 전환하고 있다. 이 중 가장 일반적인 것이 pendulum 장치인데, 고정원이 되는 전방치아의 원하지 않는 이동과 고정원 소실, 그리고 구개부 고정원이 좋지 않은 경우 원하는 정도의 구치부 원심이동을 얻기 어렵다는 단점이 있다. 이와 같은 전통적인 pendulum의 단점을 해결하고자, SAS(Skeletal Anchorage System)를 pendulum에 접목하여 골에서 직접 지지를 얻는 변형된 형태의 pendulum, 즉 bone supported pendulum을 제작하여 장착 시킨 후 주기적인 관찰을 시행하였다. 본 증례는 혼합치열기 환자를 대상으로 bone supported pendulum을 사용하여 안정된 고정원 유지, 원치 않는 치아이동의 최소화 및 양호한 상악 대구치 원심이동 등을 관찰하였기에 이를 보고하는 바이다. To distalize the maxillary molars. the traditional techniques such as extra-oral traction. Wilson distalizing arches. removable spring appliances and Schwarz plate-type appliances have been used. But, these need considerable patient cooperation. For minimal patient compliance. many practitioners use the pendulum appliances. Several clinical studies demonstrated pendulum is effective molar distalization appliance in the growing patient(using the premolars and the palate as anchorage). But unfortunately, maxillary anterior teeth also shift mesially as the molar moves distally. As a result anchorage loss is occurred. To overcome these disadvantages, we used bone-supported pendulum, combined the conventional pendulum with Skeletal Anchorage System(SAS). The miniscrew was implanted in the anterior paramedian region of the median palatal suture, which has comparatively sufficient bone thickness and is low risk to damage on the dental follicles. We report three cases, using bone-supported pendulum for the maxillary molar distalization in children. After treatment, we find out anchorage stability, minimal unfavorable anterior tooth movement and sufficient molar distalization.

경구 진정요법하에 시행한 설소대 절제술

장용걸,박호원,이주현,서현우 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.4

Tongue-tie is a congenital anomaly characterized by an abnormally short lingual frenum, which may restrict tongue tip mobility, In the neonate and infant, tongue-tie was said to cause difficult breast-feeding, In the older infant, toddler and young child, poor speech has been frequently listed because movement of tongue tip is limit ed. Also as a abnormal tongue position, various orthodontic problems, later mechanical and social manifestations could be developed. Treatment options such as observation, speech therapy, frenotomy and frenectomy have been suggested. The optimal timing for the surgery has not been determined, but early intervention may be appropriate for the children with significant tongue-tie who has the significant potential to speech difficulties and later social and mechanical problems. Sedation is an effective method for incapable of cooperative and the handicapped children, necessary to early intervention. We report three cases, using oral sedation for the frenectomy in young children with severe tongue-tie. After treatments, we could find out sufficient tongue movement and improved speech ability. 설유착증(tongue-tie)은 비정상적으로 짧은 설소대로 인하여 혀의 움직임이 제한되는 것을 의미한다. 영유아에서 심한 설유착증은 수유곤란을 야기하기도 하고, 증상이 지속적으로 존재할 때는 혀의 운동범위가 제한되어 발음문제를 야기할 수 있다. 또한 비정상적인 혀의 위치로 인해 여러 가지 교정적인 문제를 초래 할 뿐만 아니라, 기능적, 사회적 장애요소로 작용할 수도 있다. 설유착증의 치료방법으로는 관찰, 언어치료, 단순절개술 그리고 절제술 등이 있는데, 수술시기에 대한 논란은 있지만 정도가 심하여 장기간 언어장애가 지속되거나 교정적인 문제를 야기 할 것으로 판단되는 경우 조기수술이 권장되고 있다. 진정요법은 조기치료가 필요한 나이가 어리고 비협조적인 환아들이나, 신체적, 정신적 이유로 통상적 인 치과진료에 어려움이 있는 환아들에게 효과적으로 사용될 수 있는 방법이다. 본 증례는 설유착증으로 수술이 필요하나 협조전단계인 환아를 대상으로 경구투여를 이용한 진정요법으로 소대절제술을 시행하여 양호한 결과를 얻었기에 이를 보고하는 바이다.

태양광 발전 시스템 적용을 위한 관공서 전력 에너지 소비량 분석

장민호,김현진,홍원화 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1

The purpose of this study was to gather and categorize the data of electrical energy sources for public office buildings in Taegu, South Korea. The fossil energy sources are not enough for all of us, as we know, to use. In a few days, it will be hard to utilize or find them neither under the earth nor the sea or around the world. New energy sources should be recommended and solar energy has been referred to substitute these limited sources. Prior to studying solar energy sources applied to public office buildings, necessary data should be systematically surveyed and lined up. This research ,therefore, will be a very important foundation for studying next thesis, solar energy project.