캐스케이드 열펌프시스템의 운전 특성에 관한 연구

장기창(Ki-Chang Chang),백영진(Young-Jin Baik),나호상(Ho-Sang Ra),김지영(Ji-Young Kim),이재훈(Jea-Hun Lee) 한국지열·수열에너지학회 2009 한국지열에너지학회논문집 Vol.5 No.1

The purpose of this study is to investigate the performance of a water heat source cascade heat pump system R717(Ammonia) is used for a low-stage working fluid while R134a is for a high-stage. In order to gain a high temperature supply water in winter season, the system is designed to perform a cascade cycle. In this study, two experiments were carried out. One is a system starting test from the low load temperature of 10℃. The other is a system performance investigation over the R717 compressor capacity changes. Experimental results show that when it starts from the low load temperature, the suction temperature of the low-stage compressor is higher than that of a high-stage. The system performance increases when a water source temperature or a low-stage compressor rotational frequency goes higher.

SV40 T 항원의 온도조건부 변이형 유전자가 포함된 Amphotropic Retrovirus 에 의한 사람 태아 간세포의 불멸화

이정일(Joung Il Lee),동석호(Seok Ho Dong),김효종(Hyo Jong Kim),김병호(Byung Ho Kim),장영운(Young Woon Chang),장린(Rin Chang),성세라(Se Ra Seong),박재경(Jae Kyung Park),김승보(Seung Bo Kim),이상목(Sang Mok Lee) 대한내과학회 1999 대한내과학회지 Vol.57 No.1

N/A Human cells are almost never spontaneously immortalized in vitro. We tried to immortalize human fetal hepatocytes (h-FH) and evaluate the differentiational status and its change. Methods : Hepatocytes were isolated from a liver fragment of 20 week old fetus and infected with amphotropic recombinant retrovirus containing a temperature- sensitive mutant of SV40 large T antigen and neomycin phosphotransferase gene. G418 resistant colonies were cloned and expanded. The cells which were able to divide more than 30 times were used to analyze various functions. Results : The immortalization rate was 3.3 x 10-8 and two cell lines (C11, D21) were established. C11-60, C11-80, D21-30 and D21-60 (suffix number means the cell division counts) were evaluated. D21-30 was thougt to be imcompletely immortalized because a considerable portion of cells died during culture. The morphology was similar to that of epithelial cells except for D21-30 which looked like fibroblast. The cells grew rapidly at 33oC but stopped growing at 39oC. T antigen and p53 was expressed at 33oC but disappeared at 39oC, which suggest that T antigen binds to p53. Chromosomal changes were so marked that it was impossible to discriminate exact number. Albumin was secreted as about 1/10 as that of h-FH, but alpha-fetoprotein secretion stopped after immortalization. Telomerase was activated in both cell lines except for the incompletely immortalized cells D21-30. Telomere was elongated in competely immortalized cell lines, but it was rather shortened in D21-30 compared to that of h-FH. Macroscopic colonies did not develop in soft agar assay. Conclusions : We successfully immortalized human fetal hepatocytes. Although the cells are not likely to have oncogenicity, the functions are not so good, possibly due to marked chromosomal changes which are thought to occur before telomerase is activated during immortalization step.

정신분열병 환자에서 얼굴 영상의 작동기억 장애 : 기능자기공명영상연구

이창욱,김태석,주라형,박주미,박여진,김종진,전신수,배치운,김정진,이수정,이철,백인호 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.2

Objectives : Impaired processing of facial information is one of the broad ranges of cognitive deficits seen in patients with Schi-zophrenia. We aimed to elucidate the differences in brain activities involved in the process of facial working memory between schizophrenic patients and healthy comparison subjects. Methods : Twelve patients with schizophrenia were recruited along with twelve demographically matched healthy volunteers as a comparison group. Functional magnetic resonance imaging (fMRI) was used to assess cortical activities during the Perfor-mance of a 2-back working memory paradigm using images of neutral faces as mnemonic content. Rcsults : The patient group performed the tasks with reduced accuracy. Group analysis revealed that the left fusiform gyrus, the right superior frontal gyrus, the bilateral middle frontal gyri/insula, the left middle temporal gyrus, the precuneus, the quadrangular lobules and the vermis of cerebellum showed decreased cortical activities in the patient group. On the other hand, an increased level of activation in the lateral prefrontal cortex and the pahetal lobule was observed from the patient group, all in the right hemisphere. Conulusion : A decreased level of activity in the left fusiform gyrus among the patient group implicates inefficient processing of facial information. An increased level of activation in prefrontal and parietal neural networks from the patient group confirms earlier findings on the impaired working memory of patients with schizophrenia.

신생아의 병적황달에 대한 임상혈액학적 고찰

박춘호,김성의,나창수 朝鮮大學校 附設 醫學硏究所 1987 The Medical Journal of Chosun University Vol.12 No.1

A clinical and hematological observation was performed on 398 nowborn infants with hyperbilirubinemia who were admitted 10 the Department of Pediatrics, Chosun University Hospital from January, 1980 ro June, 1985. The following results were obtained 1) The incidence of hyperbilirubinemia was more frequent in male(63.8%) than in female(36.2%) 2) In the observation of the gestational period, its incidence was highest in full-term neonate(70%) and the next was pre-term neonate (25%) 3) In the observation of the delivery type, the incidence was highest in neonates with normal delivery(82.0%) and the next was c-section delivery (11.0%) 4) Idiopathic hyperbilirubinemia was the most common cause of pathological hyperbilirubinemia and the next wero breast-fed induced jaundice(10.4%), infection(9.3%), blood incompatibility(8.6%) in frequent of order. 5) The most common blood types of mother-baby in ABO blood incompatibility was 0-A (48.5%) and the next was O-B(42.5%) 6) The exchange transfusion were performed on 34 cases(8.5%). The mean serum bilirubin levels before exchange transfusion were 26.7±4.9㎎% in the cases of idiopathic hyperbilirubinemia(14 cases) and 25.9±6.5㎎% in the cases of blood incompatibility (17 cases). 7) The mean bilirubin levels before and after the exchange transfusion were 26.4㎎% and 11.9㎎% respectively and reducing rate of the bilirubin by exchange transfusion was 55%. Second exchange transfusion was performed in 2 cases(5.8%).

조기 양막 파수 신생아에 대한 임상적 연구

양은석,김강호,박상기,나창수 朝鮮大學校 附設 醫學硏究所 1989 The Medical Journal of Chosun University Vol.14 No.1

A clinical study was made on 157 newborns of mothers with premature rupture of membranes (study group) and 916 newborns of mothers without rupture of membranes (control group) at Chosun University Hospital from Jaunary 1987 to Decembcr 1988. The results were as follows: 1) The incidence of PROM was 14.6%. 2) 10.2% of all babies with PROM were born prematurely, significantly higher than the incidence of PROM in all newborn cases with 4.8% (P<0.005). 3) The incidence of neonatal sepsis in the PROM group (4.5%) was four times higher than in the normal group(1.1%) (P<0.005). The incidience was related to the gestational age at birth, and also increased with increasing time interval after PROM. 4) The incidence of neonatal asphyxia in PROM group (7.6%) was twice the normal group (3.6%) (P<0.025). The premature babies had greater incidence in both groups. Also, a positive correlation was found with increasing time interval PROM. 5) Neonatal respiratory distress syndrome(RDS) was found in 1.3% of babies with PROM, whereas 1.4% of babies in the normal group had the syndrome. Premature babies had higher incidence of RDS in both normal and PROM groups, but the latter had an incidence amounting the only 1/5 of the former. And it tended to diminish with creasing time interval after PROM.

국민학교 아동의 혈압에 관한 조사연구

구광련,유호성,나창수 朝鮮大學校 附設 醫學硏究所 1987 The Medical Journal of Chosun University Vol.12 No.1

Blood pressure measurement was done in Korean elementary school children ranging between 6 years and 12 years of age. It was carried out from April, 1986 to May, 1986. The total number of persons measured was 240 cases including 120 males and 120 females. The following results were obtained: 1) Gradual eleavation of mean blood pressure in male and female were noted with increased of the age 2) The mean blood pressure of male were slightly higher than those of female 3) The mean blood pressure of Korean elementary school children were lower than those of the Americans in both systolic diastolic blood pressure

광중합기를 이용한 광학적 치아우식활성도 검사법

이난영,김미라,오유향,이창섭,이상호 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.4

레이저와 플라스마 광, 할로겐 광 중합기를 이용하여 각 개인의 우식 활성도를 측정할 수 있는지를 규명하기 위해 7-8세 아동 45명을 대상으로 치아의 순면과 협면에 각 광원을 조사하고 특수 필터를 사용하여 초기 치아우식증으로 판별된 치아의 개수를 측정하여 기존의 우식활성도 측정방법인 dDfFtT rate와 mutans streptococci 측정법 Lactobacilli 측정법과 비교, 평가하고 그 특이도, 민감도, 예측력을 평가하였다. 1. 아르곤 레이저, 플라스마 광, 할로겐 광 조사시 육안검사시 보다 유의하게 많은 초기우식 병소가 관찰되었다(p<0.05). 2. 아르곤 레이저, 플라스마 광, 할로겐 광을 이용한 우식활성도 측정법은 dDfFtT rate와 양의 상관관계(γ= 0.42, 0.41, 0.39)를 보였다(p<0.01). 3. 기존의 우식활성도 측정방법을 기준으로 하여 평가한 결과 특이도와 민감도, 예측력은 모두 레이저가 가장 높았으며 플라스마 광, 할로겐 광 순으로 나타났다. 이상의 결과를 종합하여 볼 때 아르곤 레이저와 플라스마 광, 할로겐 광을 이용한 형광법은 모두 양호한 진단학적 지표를 보여줌으로써 향후 광학적 우식활성검사법으로 활용 가능성이 높을 것으로 사료된다. The purpose of this study was to develop a practical caries activity test by fluorescence using laser, plasma light and halogen light. The subjects of study were 45 children of 7-8 years old. Argon laser, plasma light and halogen light were irradiated to buccal or labial surface of all teeth. Fluorescence of initial carious lesion from teeth was observed through barrier filter and the number of teeth showing lesion was counted. Visual examination for the dDfFtT, mutans streptococci screening test and Lactobacilli colony counting were also done. Data analysis was accomplished by Axelsson's method. The result from the present study can be summarized as follows. 1. Laser, plasma light and halogen light could detect the initial carious lesions better than visual examination(p<0.05). 2. There was positive correlation between laser(r=0.42), plasma light(r=0.41), halogen light(r=0.39) and dDfFtT rate(p<0.01). 3. The specificity, sensitivity and predictive value was showed highest value in laser. but was showed favorable value in plasma light and halogen light. In regard to above results, laser, plasma light and halogen light all considered to be reliable method for determining individual caries activity. And they were also considered to be practical method because it would be simple, inexpensive, and time saving method.

초등학교 고학년 학생의 장애아동에 대한 인식 조사

김보람,김호영,손유라,오진주,윤슬기,이효정,장문영 대한감각통합치료학회 2011 대한감각통합치료학회지 Vol.9 No.1

목적 : 초등학교 고학년 학생의 장애아동에 대한 인식을 알아보는 것이다. 연구방법 : 연구 대상은 김해시에 소재한 통합교육을 실시하지 않는 초등학교의 4, 5, 6학년의 비장애 아동이었다. 연구 기간은 2008년 10월 2일부터 10월 17일까지였으며, 설문지를 사용하였다. 설문지의 하위 영역은 사귐, 활 동, 학업 영역의 세 부분으로 각 10문항으로 이루어져 있으며 SPSS 12.0을 사용하여 분석하였다. 결과 : 장애아동에 대한 인식조사 결과 첫째, 성별에 따른 인식은 남학생보다 여학생의 평균 점수가 높았으나 통계 적으로 유의미한 차이는 없었다. 둘째, 학년에 따른 인식은 4학년의 평균 점수가 가장 높았고 6학년이 가장 낮았으 며 통계적으로 유의미한 차이가 있었다(F=3.546, p<0.05). 셋째, 장애인 접촉 유무에 따른 인식은 접촉 경험이 없 는 학생이 있는 학생보다 평균점수가 높았으나 통계적으로 유의미한 차이는 없었다. 결론 : 비장애학생의 장애아동에 대한 인식은 학년에 따라 차이가 있었다. 본 연구는 작업치료사들에게 장애아동에 대한 또래집단의 인식에 대한 정보를 제공함으로써 학교환경에 대한 이해를 도울 수 있을 것이다. Objective : The purpose of this study was to investigate attitude of grade-schoolers toward children with disabilities. Methods : The subjects of this study were grade-schoolers who have not received an inclusive education in Gim-hae. The study was surveyed from October second to 17th in 2008. The survey was categorized into three parts; comradeship, activity, and study. Each part of the survey consists of 10 questions. Data were analyzed by SPSS (version 12.0). Results : The results were as follows; First, the attitude of girls toward disabled students was non-significant compared to boys. Second, the order of attitude degree in grade of students was 4, 6, and 5. The attitude toward children with disabilities showed statistically significant difference according to grade(F=3.546, p<0.05). Third, the attitude of students who have experience of contact with people with disabilities was non-significant compared to non-experienced students. Conclusion : In conclusion, therefore peer groups in lower class levels showed more positive attitude toward the children with disabilities. The result will be useful information for understanding disabled children and making positive attitude. Also it is expected that occupational therapists help disabled children to participate in school life successfully using these information.

천연 생약재 열수 및 알코올 추출물의 어병 세균에 대한 항균력

최혜승,김이청,이주석,조미라,서창호,박수일 한국어병학회 2004 한국어병학회지 Vol.17 No.1

감초 외 48종의 천연 생약제로부터 열수 및 알콜 추출액을 제작하여 19 균주 어병 세균을 대상으로 항균력을 조사한 결과, 알콜 추출액은 22종, 열수 추출액은 16종이 어병 세균에 대하여 항균력을 나타내며 이 중 13종의 생약재는 알콜 및 열수 추출액 모두 8㎜ 이상의 저지대를 나타내어 항균력이 있는 것으로 나타났다. 열수 추출물에서 항균력을 나타내는 약재 중 그람 음성균에 감수성이 양호한 약재는 저지대 8 ㎜ 이상을 나타내는 애엽, 개옻나무, 연교, 지유, 파엽, 대황 및 황금이었으며, 그람 양성균에 항균력이 양호한 약재는 삼지구엽초, 육계 및 보골지 등 이었다. 그리고 오매, 황련, 계혈등, 상백피, 오배자 및 오미자는 저지대가 8㎜ 이상으로 그람 음성,양성균 모두에 항균력이 있었다. 알콜 추출물중에서 그람 음성균에 항균력을 나타내는 것은 백작약, 오매, 선모 및 황금 등으로 저지대가 8㎜ 이상으로 측정되었으며, 그람 양성균에 항균력을 나타내는 것은 감초, 계혈등, 단삼, 상백피, 육계 및 보골지 등으로 저지대가 8㎜ 이상이었다. 또한 그람 음성, 양성균에 모두 8㎜ 이상의 저지대를 나타내는 것은 애엽, 개옻나무, 황련, 지유, 오배자 및 오미자 등이었다. 그러나 이 중에서 오배자 열수 추출물의 어병 세균에 대한 발육 저지대가 32㎜로 그람 음성, 양성균 모두에 가장 뛰어난 항균력을 나타내어 다른 생약재와 다른 광범위 생약재인 것으로 나타났다. 애엽, 황금, 지유, 오매, 황련 및 오배자 열수 ·알콜 추출물은 tetracycline에 내성을 나타내는 균주에 감수성을 나타내었다. Hundreds of medicinal herbs have been using for the purpose of diseases treatment and immune enhancement for human being and other animals including fishes. Among them, 49 species of medicinal herbs were selected and tested for antibacterial activities against 19 strains of fish pathogenic bacteria in different 4 species. The 49 medicinal herbs were extracted by water and ethyl alcohol. The extracts were freeze dried and some paper discs from the extracts were prepared for the evaluation of antibacterial activity. The tested pathogenic bacteria were 5 strains of Edwardsiellu tarda, 5 strains of Vibrio sp., 4 strains of Lactococcus gawieae, 1 strain of Lactococcus raffinose. 1 strain of Streptococcus parauberius, and 3 strains of Streptococcus iniue. The Galla rhois (Obaeja), Gaeonnamu and Hwangleyon showed antibacterial activities on both gram negative and gram positive fish pathogenic bacteria. The Youkgae, Sangbaekpi, Bogolji and Gamcho showed very effective antibacterial activities on gram positive pathogens while Jiyu, Aeyoeb and Yeonkyo showed very effective on gram negative pathogens.

유한한 열용량의 열원 및 열침 조건에서 열기관의 출력 최적화

백영진(Young-Jin Baik),김민성(Minsung Kim),장기창(Ki-Chang Chang),이영수(Young-Soo Lee),라호상(Ho-Sang Ra) 대한설비공학회 2011 대한설비공학회 학술발표대회논문집 Vol.2011 No.7

In this study, the theoretical maximum power of a heat engine was investigated by sequential Carnot cycle model, for a low-grade heat source of about 100℃. In contrast to conventional approaches, the pattern search algorithm was employed to optimize the two design variables to maximize power. Variation of the maximum power and the optimum values of design variables was also investigated for a wide range of UA(overall heat transfer conductance) change. The results show that the maximizing heat source utilization not always maximize power.