주강계 저열팽창 주조합금의 열팽창 계수와 경도에 미치는 Mo , V 첨가의 영향

김영한,윤의박,문병문,홍영명 ( Young Han Kim,Eui Park Yoon,Byoung Moon Moon,Young Myung Hong ) 한국주조공학회 1998 한국주조공학회지 Vol.18 No.5

N/A For enhancing the mechanical properties of LTE (low thermal expansion) cast steel, systematic researches have been carried out. The effects of alloying elements such as vanadium, molybdenum and carbon on the hardness and linear thermal expansion coefficient were investigated. In the range of 0.5∼2.3 wt% carbon, addition of 1.73 wt% carbon caused hardness increase due to the formation of eutectic carbide having high hardness but over the range of 1.73 wt% carbon, hardness was decreased. Thermal expansion coefficient increases with carbon contents. In the LTE cast steel containing 0.6 wt% carbon, hardness increased up to 1.96 wt% vanadium addition. But over the range of 1.96 wt% vanadium hardness was decreased by coarse eutectic carbide. Thermal expansion coefficient of LTE cast steel containing 0.6 wt%carbon moderately increased with increasing vanadium contents. There was no significant variation of hardness and thermal expansion coefficient according to molybdenum content in LTE cast steel. (Received June 29, 1998)

연소 유동장의 PIV 가시화 측정과 제반 문제들

김영한,윤영빈,정인석,Kim, Young-Han,Yoon, Young-Bin,Jeung, In-Seuk 대한기계학회 2000 大韓機械學會論文集B Vol.24 No.4

PIV(Particle Image Velocimetry) is a recently developed technique for visualizing the fluid velocity fields. Because it has several advantages over the LDV(Laser Doppler Velocimetry), it became one of the most popular diagnostic tools in spite of its short history. However, its application to combustion is restricted by some problems such as flame illumination, scattered light refraction, particle density variation due to heat release, the combined effect of abrupt change in particle density and fluid velocity on flame contour, and thermophoresis which is particle lagging due to temperature gradient. These problems are expected to be originated from the non-continuous characteristics of flames and the limitations of particle dynamics. In the present study, these problems were considered for the visualization of the instantaneous coaxial hydrogen diffusion flame. And the instantaneous flame contour was detected using particle density difference. The visualized diffusion flame velocity field shows its turbulent and meandering nature. It was also observed that the flame is located inside the outer shear layer and flame geometry is largely influenced by the vorticity.

LCFQ ( Linear Clock Fair Queueing ) 알고리즘의 설계와 성능 분석

김영한,이재용,Kim, Young-Han,Lee, Jae-Yong 대한전자공학회 1999 電子工學會論文誌, S Vol.s36 No.1

종합 서비스망에서, 트랙픽을 발생시키는 각각의 플로우에 대하여 QoS(Quality of Service)를 적절하게 제공하기위해서는 호스트와 라우터에 자원 예약뿐만 아니라 효율적인 트랙픽 스케쥴링이 채택되어야 한다. 본 논문에서는 가상시간이 선형적으로 증가하는 새로운 페어 큐잉 알고리즘에 제안한다. 본 논문에서 제안된 알고리즘은 각 플로우에 대하여 기존의 SCFQ(Self-Clocked Fair Queneing) 알고리즘과 유사한 구현 복잡성을 갖으면서 더 감소된 최대 지연와 평균 지연시간을 제공하고 공평성 측면에서도 개선됨을 보여준다. 또한 자신에게 할당된 대역폭보다 더 많은 트랙픽을 발생시키는 플로우에 의해 다른 플로우는 영향을 받지 않도록하는 독립성 특성 또한 SCFQ보다 더 좋은 성능을 보인다. 본 논문에서는 제안된 알고리즘에 대한 공평성을 증명했고, 최대지연과 평균지연시간에 대한 시뮬레이션 결과를 나타냈다. In order to provide appropriate Quality of Service(QoS) guarantee to each traffic flow in intergrated service networks, an efficient traffic scheduling algorithm as well as resource reservation must be adopted in host and transit routers. In this paper, a new efficient fair queueing algorithm which adopts a linearly increasing virtual time is presented. The proposed algorithm is fair and the maximum and mean delay guaranteed of each flow are less than those of the SCFQ(self clocked fair queueing) algorithm which is one of the most promising traffic scheduling algorithm, while providing low implementation complexity as the SCFQ scheme. And, it has the better isolation provided than SCFQ, which means that each flow is much less influenced by the violating traffic flows provided its allocated bandwidth gurantee. The fairness of the proposed algorithm is proved and simulation results of maximum and mean delay presented.

Neonatal Onset Isovaleric Acidemia with Novel Mutation

김영한,배은주,박형두,이홍진,Kim, Young Han,Bae, Eun Ju,Park, Hyung-Doo,Lee, Hong Jin The Korean Society of Inherited Metabolic Disease 2016 대한유전성대사질환학회지 Vol.16 No.1

Isovaleric acidemia is autosomal-recessively inherited and an inborn error of metabolism caused by abnormal leucine metabolism due to the genetic defect of IVD (Isovaleryl-CoA dehydrogenase). IVD corresponds to mitochondrial matrix enzyme that acts on converting isovaleryl-CoA into 3-methylcrotonyl-CoA in the leucine catabolism. The IVD gene is located at Chromosome 15q14-q15, particularly between base pair 40,405,485 and base pair 40,435,948. It consists of 12 exons and has been reported to cause over 50 diseases so far. We conducted IVD gene test on the patient with acute isovaleric acidemia and confirmed a new type of mutation for the first time. As a result of analyzing the IVD gene sequence, we found out that c.129T>G(p.Asn43Lys) and c.1033A>G(p.Asn345Asp) mutations exist as heterozygosity at Exon 1 and Exon 10 respectively, novel mutation.

도재전장주조관의 순측 치경부 변연 적합도에 관한 주사전자현미경적 연구

김영한,이선형,Kim, Young-Han,Lee, Sun-Hyung 대한치과보철학회 1985 대한치과보철학회지 Vol.23 No.1

The purpose of this study was to evaluate the marginal fitness of collarless metal-ceramic crown formed with direct lift technique using wax compared with metal-ceramic crown with metal butt margin. Twenty crowns, ten were collarless metal-ceramic crowns and ten were metal-ceramic crowns with metal butt margins, were made and cemented on epoxy resin dies, and their marginal openings were measured on scanning electron microphotographic prints at x200 magnification. The results were as follows; 1. In the case of collarless metal-ceramic crowns, the mean marginal opeining was $43.78{\pm}17.67{\mu}m$, the mean maximum marginal opening was $52.81{\pm}19.81{\mu}m$, and the mean minimum marginal opening was $34.99{\pm}16.58{\mu}m$. 2. In the case of metal-ceramic crowns with metal butt margins, the mean marginal opening was $47.62{\pm}25.55{\mu}m$, the mean maximum marginal opening was $61.90{\pm}24.39{\mu}m$, and the mean minimum marginal opening was $34.86{\pm}24.92{\mu}m$. 3. There was no significant difference between two types of crowns at the 99% confidence level. 4. The marginal fitness of collarless metal-ceramic crown formed with direct lift technique using wax was clinically acceptable.

열처리에 의한 도재용 Ni-Cr합금 표면의 변화에 관한 연구

김영한,이선형,양재호,정헌영,Kim, Young-Han,Lee, Sun-Hyung,Yang, Jae-Ho,Jung, Heon-Young 대한치과보철학회 1989 대한치과보철학회지 Vol.27 No.2

The purposes of this study were to analyze the microstructural and compositional changes of metal surfaces following different conditions of preoxidizing heat treatment, to investigate the composition of metal oxides, and to evaluate the effect of preoxidation and removal of surface oxides on microstructure and diffusion profiles. The techniques of EDAX (energy-dispersive analysis of x-ray), ESCA (electron spectroscopy for chemical analysis), and EPMA (electron probe micro analysis) were used, along with SEM (scanning electron microscopy). The obtained results were as follows : 1. A surface of the specimen became rough and the amount of the metal oxides increased with increasing the heat treatment time and temperature and the partial pressure of oxygen. 2. At an air pressure of 28' vacuum, the higher the temperature and the longer the time of preoxidation, the higher Ni concentration was detected. 3. Cr concentration in the specimen heat treated with air was higher than that of with vacuum. 4. The oxides in the specimens were mainly composed of Ni and Cr oxides. On the globular growth particles, significant rises in Al concentration of Rexillium III and Ti concentration of Verabond were noted. 5. Atomic diffusion occurred at the ceramic-metal interface, furthermore the amount of the flux was increased with preoxidation heat treatment.

사립체 질환: 새로운 위대한 모방자가 될 것인가?

김영한,안석민,서영준,윤종형,배은주,이홍진,Kim, Young Han,Ahn, Seok Min,Seo, Young Jun,Yoon, Jong Hyung,Bae, Eun Ju,Lee, Hong Jin 대한유전성대사질환학회 2016 대한유전성대사질환학회지 Vol.16 No.3

Mitochondrial disease is a group of disorders caused by dysfunctional mitochondria, the organelles that generate energy for the cell. Diagnosis of mitochondrial disease is difficult, subtle, and has many problems. It is more likely to miss the diagnosis of mitochondrial disease, especially in borderline cases where the symptoms of the disease are not severe. In this regard, urine organic acid analysis is noninvasive and can increase the sensitivity and specificity through repeated load test with few changes according to the specimen. And, It is considered to be suitable as a screening test for mitochondrial diseases because it has a great advantage of distinguishing from organic aciduria, urea cycle disorder and fatty acid oxidation disorder which may have similar symptoms. The purpose of this study was to investigate the clinical features and age distribution of mitochondrial diseases diagnosed by organic acid analysis and to establish the policy of diagnosis and treatment based on this study.

조산의 예측에 있어 산모의 질 분비물내 Nitrate 와 Nitrite 측정의 유용성

김영한 ( Young Han Kim ),이창희 ( Chang Hee Lee ),박용원 ( Yong Won Park ),조재성 ( Jae Sung Cho ) 대한산부인과학회 2001 Obstetrics & Gynecology Science Vol.44 No.7

N/A Objective :This study is directed to determine whether the concentrations of nitrate and nitrite, metabolites of nitric oxide, in vaginal secretions could be used to predict a premature delivery. Method: A total of 60 pregnant women from March, 2000 to February, 2001 received continuous prenatal care and underwent delivery in our hospital was enrolled in the study. Gestational age was ranged between 20 and 37 weeks. Those patients were divided into four groups according to clinical parameters such as preterm labor, premature rupture of membranes and premature delivery. Specimens were obtained by though washing of vagina with 5 mL sterile physiologic sodium chloride solution for determination of nitric oxide metabolites. The total nitrate and nitrite concentration was determined by treatment with nitrate reductase followed by the Griess reaction. Results : Subjects were divide into four groups (group I, no preterm labor and term delivery [n=19]; group II, preterm labor and term delivery [n=12]; group III, preterm labor and consequent premature delivery [n=6]; Group IV, preterm labor with premature rupture of membranes and consequent premature delivery [n=23] ). Total nitrate and nitrite concentrations in group II-IV (62.2±50.3 μpmol/L in group II, 113.3±77.0μpmol/L in group III, 101.94±72.4μpmol/L in group IV) were significantly higher than the concentration in Group I (9.44±11.9μpmol/L). From the receiver operating characteristic curve in the prediction of premature delivery, we set 27.6 p μmol/L as a cut-off value in this study. Sensitivity, specificity, positive predictive value, and negative predictive value were 71.9%, 78.6%, 79.3%, and 71.0%, respectively. Conclusion :Patients with premature delivery do have increased nitric oxide metabolites in vaginal secretions. These results suggest that nitric oxide may be involved in the initiation of cervical ripening and used as a predictor of premature delivery.

MGL 훈련이 발달장애아의 대,소근육 운동 능력 및 사회적 기능 향상에 미치는 효과

김영한 ( Young Han Kim ),길민영 ( Min Young Kil ) 한국초등특수교육학회 2009 초등특수교육연구 Vol.11 No.1

본 연구는 MGL 훈련이 발달 장애 아동의 대근육·소근육 운동 능력 및 사회적·대인관계 기능 향상에 미치는 효과를 알아보고자 하는데 그 목적이 있다. 연구의 목적을 달성하기 위하여 발달 장애아 4명을 대상으로 6개월에 걸쳐 아동에게 적합한 훈련을 적용하고, 대·소근육 운동 능력에 미치는 효과를 MSTB A, B형으로 변화 추이를 측정하였다. 또한 사회성에 미치는 효과를 사회성숙도 검사로 변화 추이를 측정하였고, 대인 관계 효과는 대인 관계 전략 기준 평가를 이용하여 알아보았다. 연구결과 첫째, MGL 훈련이 발달 장애아 4명의 대·소근육 운동 능력에 미치는 효과를 알아보았는데, 네 아동이 훈련 전 검사보다 훈련 12주 후, 24주 후에 운동능력의 향상정도가 더 크게 향상되었음을 알 수 있었고 둘째, MGL 훈련이 발달 장애아 4명의 사회성 향상에 미치는 효과를 알아보았는데, 네 아동이 훈련전 보다 훈련 12주 후, 24주 후의 사회지수가 10점이상 향상됨을 알 수 있었다. 셋째, MGL 훈련이 발달 장애아 4명의 대인관계 변화에 미치는 효과를 알아보았는데, 네 아동이 훈련전 보다 훈련 12주 후, 24주 후에 0수준과 1수준의 행동의 빈도는 줄어드는 반면, 2수준과 3수준의 행동의 빈도는 증가함으로써 바람직한 방향으로 효과를 보이기 시작하였다. 이상의 결과에서 볼 때 MGL훈련을 통하여 대,소근육 운동능력의 협응이 원만히 이뤄지고, 타인을 인식하고 배려해 주며 상호 협력하면서 자기 중심적인 사고에서 탈피하여 점차 자신이외의 다른 사람에 대한 관심이 증가되고 다른 사람과의 사회적 접촉에 대한 자발성이 증가되어 사회적 성숙에 영향을 받는 것을 알 수 있었다. The purpose of this study was to examine how the MGL training has an effect on the development of the Gross Motor Skills and the Fine Motor Skills and the social maturity and interpersonal relationship. And the MGL training which is Frostig`s Movement education program was reconstituted, applied and practiced for 6 months. The subjects of this study were four elementary level children from I elementary school in Seo-san. Their intelligence was measured with instraments of KEDI-WISC test and social maturity scale. The results of this study were as follows; First, the MGL training turned out to be very effective on the Gross Motor skills and Fine Motor skills. This training has showed an noticeable improvement in individual Gross-Fine Motor skills effect. Second, the MGL training turned out to be very effective on the improvement of the function of social maturity. This training was showed an noticeable improvement in individual socailization effect. Especially in work ability, self discipline ability, communication and social ability of children. Third, the MGL training turned out to be very effective on the interpersonal relationship skills are improved as follows. As inter children activities grow more and more positively through the MGL training, imterpersonal strategy use in inter children activities also shows at a higher level. Furthermore the MGL training helps the developmental disability children grow socially and improves their interpersonal relationship skills, thus making them able to function in a regular social environment. The developmental disability children they may realize the existence of others and thus form such a friendly and harmonious interpersonal relationship that they can get along with those who are around them better in everyday`s activities. From the results of this study, I`d like to make some suggestions; First, the study had observed the children for only 6 months. A longer period of time should be needed to fine out more positive changes in their motor skills development. Second, proper teaching methods and its tools should be developed, which would fit into degrees of their disability. Third, further studies were suggested that various and specific measures for the practical application of this program were to be applied.

스프링클러 관수 ‘후지’ 사과나무에서 수분관리를 위한 토양수분센서들의 비교

김영한(Young Han Kim),전익조(Ik-Jo Chun) 한국원예학회 2023 한국원예학회 학술발표요지 Vol.2023 No.5