A Case of Urethral Stent for Recurrent Urethral Stricture and Penile Prosthesis for Erectile Dysfunction

Jung, Gyung-Woo,Song, Young-Jin,Park, Young-Ho,Kwon, Heon-Young,Yoon, Jin-Han 동아대학교의과대학 1992 동아의대학술지 Vol.4 No.1

Development of High efficiency Food Waste Treatment System for Entering New and Renewable Energy Industry in Southeast Asia

Kwon,Ki-Tae,Lee,Woo-Sik,Kwon,Lee-Seung,Seong,Seung-Hwan,Kim,Young-Do,Kwon,Woo-Taeg 한국유통과학회 2019 KODISA ICBE (International Conference on Business Vol.2019 No.-

It is possible not only to treat high concentration organic matter such as food wastes but also to utilize food wastes as resources according to the bio-energy generation such as methane. The method of co-digestion of mixed wastewater mixed with organic wastes such as sewage sludge concentrated waters together with drinking wastewater is the most ideal method. Radiation not only has germicidal power in water treatment, but also is effective in decomposing degradable organic matter. Second chemical contamination problem is also solved because it does not use chemicals. Introduction of radiation pretreatment system to solve problems caused by mixing of waste water and organic waste resources. Biological electrochemical fusion system is used to remove the nutrients contained in the organic matter-removed mixture. Through the development of a system for treatment of high concentration wastewater, the processing efficiency is verified through the universal water treatment system for wastewater containing high concentration organic matter in addition to treatment of wastewater.

Mechanical Characterization of Nano-Structured Materials Using Nanoindentation

( Ju Young Kim ),( Sung Hoon Kim ),( Jung Suk Lee ),( Kyung Woo Lee ),( Dong Il Kwon ) 대한금속재료학회 ( 구 대한금속학회 ) 2006 METALS AND MATERIALS International Vol.12 No.3

The principal strengths of the nanoindentation technique, which is used extensively to measure the mechanical properties of nano/micro materials, are easy sample preparation and simple experimental method. Hardness and Young`s modulus are essential properties measured by nanoindentation; hardness corresponds to resistance to plastic deformation whereas Young`s modulus is related to elastic deformation. Two key difficulties arise in association with nanoindentation on small volumes: measurement accuracy and material response. Here we discuss the indentation size effect (ISE) considering tip bluntness and variation in hardness of nano-multilayers with a bilayer period, representative research on measurement improvement, and material response at nanoscales.

중ㆍ고년여성의 하지 근 기능과 요부 및 대퇴근 횡단면적의 상관관계

김창근,이수경,권영우,박정배 한국체육대학교 체육과학연구소 2001 국제학술대회논문집 Vol.20 No.1

The purpose of the present study was to investigate the relationship between isokinetic muscle function and muscle cross-sectional area (CSA). Twelve women participated in the present study, divided young (n=6, 23.7±1.9 year) and elderly women (n=6, 60.3±6.8 year). Isokinetic strength (power, strength, endurance) and CSA (psoas major and thigh muscles) measured with dynamometer and computerized tomograph, respectively. Cross-sectional area of psoas major muscle in elderly group revealed markedly smaller than in young group, but thigh muscle was not the case. Muscle CSA in young women correlated between power and endurance and psoas major muscle, as well as between muscle strength and CSA of thigh muscle. But no correlation occurred between strength and cross sectional area, except endurance which was highly correlated between CSA and endurance. In conclusion, aging decreases muscle function and CSA. Partially muscle strength correlated with muscle CSA in young women, but no correlation occurred in elderly women. Further study needed to elucidate the exact mechanism related to aging muscle with muscle density and neuromuscular function.

노화가 인체 중간엽 줄기세포로부터 조골세포로의 증식 및 분화에 미치는 영향

백기현,태현정,오기원,이원영,조정기,권순용,강무일,차봉연,이광우,손호영,강성구,김춘추 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.3

연구배경: 일반적으로 골다공증과 연관된 위험인자로는 연령, 폐경, 약물, 불충분한 칼슘섭취, 만성질환 및 운동부족 등이 있는데, 특히 노화가 진행할수록 골밀도가 감소하는 것은 잘 알려져 있다. 노화와 관련하여 진행되는 골소실은 조골세포 및 전구조골세포의 기능적 결핍에 의한 골형성의 감소가 주요한 요인으로 여겨지고 있다. 그 동안 연령이 조골모 세포의 양과 조골모 세포로부터 성숙조골세포로의 분화 및 증식에 미치는 영향에 대한 일부 보고들이 있었으나 아직 일치된 견해는 없는 형편이다. 방법: 다양한 연령의 사람으로부터 골수를 채취, 중간엽 줄기세포가 포함된 단핵세포를 분리한 후 조골세포로 분화하기 좋은 조건하에서 배양하였다. 대상군은다시 젊은군과 노령군으로 구분하여 다양한 변수를 비교 분석하였다. 일차배양에서는 CFU-F를 계수하여 골수내 중간엽 줄기세포의 수를 추산하였고, 칼슘측정을 통하여 기질의 무기화 정도를 비교하였다. 계대배양후 이차배양에서는 시기별로 알카리성 포스파타제 활성도를 측정하고 오스테오칼신 mRNA의 발현을 관찰하여 젊은군과 노령군 사이의 증식능 차이를 비교하였다. 또한 이차배양 시기별로 MTT 측정을 하여 양군간에 증식능 차이가 있는지 알아보았다. 결과: 1. 일차배양 15일째에 평균 CFU-F의 수는 젊은군에서 유의하게 많았다(젊은군 148.3±28.9, 노령군 54.3±9.1, p=0.02). CFU-F의 평균면적은 젊은군에서 넓은 경향을 보였으나 통계적으로 유의하지는 않았다. 2. 일차배양 17일 경과 후 양군간에 기질 칼슘 침착정도는 유의한 차이를 보이지 않았다(젊은군 103.6±50.6, 노령군: 114.0±56.5, p=NS). 3. 이차배양 10일째에 젊은군에서 알카리성 포스파타제 활성도가 고령군에 비해 유의하게 높았다(젊은군: 935.5±115.0 U/mg, 노령군: 578.4±115.7U/mg,p.0.05). 고령군에서는 시간 경과에 따른 변화가 미약했으며 전반적으로 알카리성 포스파타제의 활성도가 젊은군에 비해 낮았다. 4. 이차배양도중 오스테오칼신 mRNA의 발현은 배양시기별로 젊은군에 비해 고령군에서 더 낮은 경향을 관찰할 수 있었다. 5. 이차배양 10일과 15일에 젊은군에서 노령군보다세포증식이 유의하게 증가된 양상을 보였다(10앓 젊은군 0.73±0.05, 노령군 0.58±0.04, p=0.05, 15일; 젊은군 0.80±0.05, 노령군 0.70±0.03, p=0.05).결론: 이상의 연구에서 저자들은 노령군에서 젊은군보다 골수 내 중간엽줄기세포의 수가 적고, 노령군에서 유래한 전구조골세포의 성숙조골세포로의 증식 및 분화가 젊은군 보다 감소해 있는 것을 관찰할 수 있었다. Background: Osteoblasts originate from osteoprogenitor cells in bone marrow stroma, termed mesenchymal stem cells (MSCs) or bone marrow stromal cells. Each MSC forms colonies (colony forming units-fibroblasts [CFL-Fs]) when cultured ex vivo. There are some reports about the age-related changes of the number and osteogenic potential of osteoprogenitor cells, but any relationship has not been clearly established in humans. In this study, we counted MSCs using CFU-Fs count and examined the proliferative capacity and differentiation potential of osteoprogenitor cells. Finally, we analyzed how these parameters varied with donor age. Methods: Bone marrow was obtained from the iliac crest of young (n=6, 27.2±8.6 years old) and old (n= 10, 57.4k6.7 years old) healthy donors. Mononuclear cells, including MSCs, were isolated and cultured in osteogenic medium. In primary culture, we compared the colony-forming efficiency of MSCs between the two groups and determined the matrix calcification. When primary culture showed near confluence, the cells were subcultured. Alkaline phosphatase activity, osteocalcin expression by RT-PCR and proliferative potential by MTT assay were examined by the time course of secondary culture. Results: At the 15th day of primary culture, the mean number of CFU-Fs was significantly higher in the younger donors (young: 148.3±28.9, old: 54.3±9.1, p=0.02) and the mean size of CFL-Fs was also larger in the younger donors than the older donors. However, matrix calcification was not different between the two groups (young: 103.6±50.6, old: 114.0±56.5, p=NS). In secondary culture, alkaline phosphatase activities were significantly lower in the older donors. The younger donors showed peak alkaline phosphatase activity at day 10, while the older donors didn't showed a remarkable peak (young: 935.5±115.OU/mg, old: 578.4±115.7U/mg, p<0.05). Total cell number as a proliferative index increased progressively during the secondary culture and a significantly greater cell number was noted in the younger donors. Osteocalcin expression was generally upregulated in the younger donors, but this was not statistically significant. Conclusion: Our study shows that the number of osteoprogenitor cells is decreased during aging and that the proliferative capacity and differentiation potential of osteoprogenitor cells seem to be reduced during aging (J Kor SOC Endocrinol 18:296-305, 2003).

소규모 하수처리를 위한 파일럿 규모 이중슬러지 KNR^® (Kwon's nutrient removal) 시스템의 영얌염류 제거성능 평가

안진영,권중천,김윤학,정유훈,김두언,유선호,김병우,An, Jin-Young,Kwon, Joong-Chun,Kim, Yun-Hak,Jeng, Yoo-Hoon,Kim, Doo-Eon,Ryu, Sun-Ho,Kim, Byung-Woo 한국청정기술학회 2006 청정기술 Vol.12 No.2

본 연구에서 소규모 하수고도처리를 위한 이중슬러지(Dual sludge) $KNR^{(R)}$ (Kwon's nutrient removal) 시스템이 개발되었다. $KNR^{(R)}$ 시스템은 부유성장식 탈질미생물과 부착성장식 질산화미생물을 분리시킨 이중슬러지 공정으로 최초침전조, 혐기조, 무산소조, 농축조의 복합기능을 수행하는 UMBR (Upflow multi-layer bioreactor)과 펠렛형 담체가 충진된 호기성 담체조로 구성되어 있다. 소규모 하수처리시 본 개발공정의 안정성과 처리성능을 평가하기 위해 처리용량 $50m^3/d$ 규모의 파일럿 플랜트를 고도처리 공정으로 개선공사 중인 처리용량 $50m^3/d$ 규모의 실제 소규모 마을하수처리장에 적용하였다. UMBR과 담체조의 체류시간은 각각 4.7 h와 7.2h이었으며, 반응조 수온은 $18.1{\sim}28.1^{\circ}C$이었다. 유입 하수량과 유입수의 BOD/N의 변동폭이 컸음에도 불구하고 파일럿 플랜트는 안정된 처리성능을 보였다. 전체 실험기간 중 처리수의 $COD_{cr}$, $COD_{Mn}$, $BOD_5$, TN, TP의 평균 농도는 11.0 mg/L, 8.8 mg/L, 4.2 mg/L, 3.5 mg/L, 9.8 mg/L, 0.87/0.17 mg/L (poly aluminium chloride(PAC) 투입/미투입)이었으며, 제거율을 각각 95.3%, 87.6%, 96.3%, 96.5%, 68.2%, 55.4/90.3% 이었다. 잉여슬러지 발생량은 $A_2O$와 Bardenpho 등과 같은 단일슬러지를 이용하는 고도처리공정과 비교시 약 1.9~3.8배 낮은 $0.026kg-DS/m^3$ and 0.220 kg-DS/kg-BOD로 나타났다. A simple dual sludge process, called as $KNR^{(R)}$ (Kwon's Nutrient Removal) system, was developed for small sewage treatment. It is a hybrid system that consists of an UMBR (Upflow multi-layer bioreactor) as anaerobic and anoxic reactor with suspended denitrifier and a post aerobic biofilm reactor, filled with pellet-like media, with attached nitrifier. To evaluate the stability and performance of this system for small sewage treatment, the pilot-scale $KNR^{(R)}$ plant with a treatment capacity of $50m^3/d$ was practically applied to the actual sewage treatment plant, which was under retrofit construction during pilot plant operation, with a capacity of $50m^3/d$ in a small rural community. The HRTs of a UMBR and a post aerobic biofilm reactor were about 4.7 h and 7.2 h, respectively. The temperature in the reactor varied from $18.1^{\circ}C$ to $28.1^{\circ}C$. The pilot plant showed stable performance even though the pilot plant had been the severe fluctuation of influent flow rate and BOD/N ratio. During a whole period of this study, average concentrations of $COD_{cr}$, $COD_{Mn}$, $BOD_5$, TN, and TP in the final effluent obtained from this system were 11.0 mg/L, 8.8 mg/L, 4.2 mg/L, 3.5 mg/L, 9.8 mg/L, and 0.87/0.17 mg/L (with/without poly aluminium chloride(PAC)), which corresponded to a removal efficiency of 95.3%, 87.6%, 96.3%, 96.5%, 68.2%, and 55.4/90.3%, respectively. Excess sludge production rates were $0.026kg-DS/m^3$-sewage and 0.220 kg-DS/kg-BOD lower 1.9 to 3.8 times than those in activated sludge based system such as $A_2O$ and Bardenpho.

이륜차 무단변속기(CVT) 구동풀리의 시물레이션

권영웅,우영환,이종원,길성진 중앙대학교 생산공학연구소 1999 생산공학연구소 논문집 Vol.8 No.2

CVT 메카니즘은 공학적 분야에 많이 사용되고 있으며, 특히 CVT의 구동폴리느 중요한 역할을 한다. 본 연구에서는 이륜차의 CTV를 국산화 할 계획의 일환으로 구동폴리를 시뮬레이션하였다. 시뮬레이션한 결과느 구동폴리의 롤로 무게와 마찰 계수, 램프의 각변형을 통해 나온 수치르 장량화한 것이며, 이를 토대로 구동폴리의 각 요소들 즉, 롤러와 유동플랜지, 램프판 간의 상호관계를 규명하였다. CVT(Continuously Variable Transmission) mechanism has been used in many engineering applications. A driving pulley of CVT plays a vital role. In this study, computer simulation for a movable pulley was carried out for the purpose of producing a motorcycle CVT of Korean model. The effects of roller mass, friction coefficient, deformation of ramp plate on a given speed and torque during moving were quantified using the simulation results. Based on the simulation, relations between each component of driving pulley that consists of roller, movable flange and ramp plate etc. were investigated.

병렬 객체지향 표기 언어에서의 통신과 동기화를 위한 객체 관리기

권혁찬,최숙영,유우종,유관종 충남대학교 기초과학연구소 1995 忠南科學硏究誌 Vol.22 No.2

In this paper, we present the design and implementation of object manager for communication and synchronization in POOSL(Parallel Object-Oriented Specification Language). POOSL is a specification language which is based on object-oriented concepts and provides various granularities of parallelism and communication methods. An object manager handles synchronization of objects and supports three types of communication, that is, synchronous, asynchronous and future type communication. Object manager is automatically generated in the phase of translation of POOSL. We implemented the object manager using lex and yacc.

상백피에서 추출한 단백질 분해효소의 특성

권순경,박상욱,최우영 한국식품영양학회 1998 韓國食品營養學會誌 Vol.11 No.5

상백피에서 추출한 단백질 분해효소의 효소적 성질을 분석하였다. 상백피 추출액으로부터 분리한 단백질 함량은 1.12mg/ml, protease는 비활성도로서 5.14U/mg 수준이었다. 효소의 기질에 대한 특이성은 casein을 100으로 하였을 때 albumin 63, collagen 58, hemoglobin 45, gelatin 36의 비율로 가수분해하여 육류 단백질에 주로 함유된 collagen, hemoglobin을 분해하는 능력이 비교적 큰 것으로 나타났다. 효소의 최적온도는 60℃, 열안정성은 50∼80℃로서 비교적 열에 안정하였다. 효소의 최적 pH는 6.0이었으며 pH 6.0∼7.0에서 안정하였고 pH 9.0 이상에서는 활성이 급격히 저하되었다. 따라서 옛날부터 가정에서 고기를 삶을 때 연회를 위하여 사용하였던 상백피 중에 단백질 분해효소력이 존재함을 확인하였다. Water extract of mulberry tree barks(Morus alba Linne) was studied for its proteolytic activity. Protein content of the extract was 1.12 ㎎/ml and its specific activity was 5.14 U/ml. The enzyme was active on various proteins : the relative acitities were 100 for casein, 63 for albumin, 58 for collagen, 45 for hemoglobin and 36 for gelatin, respectively. These suggested that the ability of the enzyme to hydrolyze meat was relatively high since those are major meat proteins. Optimum pH and temperature for proteolytic activity were : pH 6.0 and 60℃. And the enzyme was stable at the pH range of 6.0 to 7.0 and temperature between 50 and 80℃. Apparent proteolytic activities could support some scientific grounds of traditional application of mulberry tree barks to home cooking for meat tenderization.

Cyclodextrin Glucanotransferase와 Cyclodextrinase를 생산하는 Bacillus 속 세균의 분리와 그 효소들의 특성

권현주,남수완,김광현,곽영규,김병우 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.3

토양으로부터 CGTase와 CDase를 함께 분비·생산하는 내열성 세균을 분리하였으며, 동정결과 Bacillus stearothermophilus로 판명되어 KJ16으로 명명하였다. Bacillus stearothermophilus KJ16 균주는 회분배양할 경우 2단계 성장을 하며 일차증식기에 CGTase를 생산하고 이차증식기에 CDase를 생산하는 양상을 보였다. 배치 pH를 7.0으로 조절하면서 배양할 경우, CGTase는 균의 증식에 따라 증가하고 CDase는 CGTase보다 뒤에 생산되었다. 그 생산양은 pH 비조절 배양에 비해 CGTase는 최대 12배(1300 mU/ml)까지, CDase는 2배(225 mU/ml)정도 증가되었다. 분리균주가 생산하는 CGTase는 분자량이 65,000 dalton으로 pH 6.0, 60℃에서 최적활성을 보이며 HPLC 분석을 통해 α-, β-, γ-CD를 42: 46: 12의 비율로 생산하는 α/β 혼합형 CGTase였다. 또한 CDase는 분자량이 68,000 dalton으로 pH 6.0, 55℃에서 최적활성을 보이며 최적기질은 γ-CD였다. A bacterium named as Bacillus stearothermophilus KJ16. The growth of the isolated strain occurred in two steps, and syntheses of CGTase and CDase were dependent on the growth cycle of the cell. CGTase was constitutively synthesized during the 1st growing phase, while CDase was synthesized inducibly during the 2nd growing phase. When the medium pH was controlled at 7.0, the maximun enzyme activities of CGTase and CDase were increased by 12-fold(1300 mU/ml) and 2-fold (225 mU/ml), respectively, compared with the pH-uncontrolled batch culture. The CGTase of the isolate converted soluble starch to CDs with the ratio of α-CD: β-CD: γ-CD=42:46:12 at 55℃. The optimal pH and temperature of CGTase were 6.0 and 60℃, respectively and the optimal pH and temperature of CDase were 6.0 and 55℃. The molecular weights of the purified CGTase and CDase were estimated to be 65,000 and 68,000 dalton, respectively. Among serveral substrates, γ-CD was most rapidly hydrolyzed by the purified CDase.