C-dump Converter에 의한 차량용 스위치드 릴럭턴스 전동기 구동 시스템의 고성능 제어

김도군(D.K. Kim),윤용호(Y.H. Yoon),이태원(T.W. Lee),원충연(C.Y. Won),김영렬(Y.R. Kim) 전력전자학회 2003 전력전자학술대회 논문집 Vol.2003 No.7(2)

Recently, SRMs are used in automobiles for power assistant steering, accessory motion control and traction drives. Especially in the motion control and traction drives, safety and efficiency are of paramount important. The paper describes the essential elements, faced in designing and constructing drive circuits for a switched reluctance motor for automobiles<br/> These converters will be referred to as energy efficient C-dump converter and modified C-dump converter. Energy efficient C-dump converter topology eliminate all the disadvantages of the C -dump converter without sacrificing its attractive features, and also provide some additional advantages that have lower number of power devices, full regenerative capability, free-wheeling in chopping or PWM mode, simple control strategy, and faster demagnetization during commutation. The experiments are performed to verify the capability of proposed control method on 6/4 salient type SRM.<br/>

육우 수정란의 간역동결 및 융해방법에 관한 연구 1 . PMSG , HCG 투여가 가토 과배란 유기에 미치는 영향

김중계(J . K . Kim),김철균(C . K . Kim),이규훈(K . H . Lee),김동철(D . C . Kim),강민수(M . S . Kang) 한국축산학회 1988 한국축산학회지 Vol.30 No.9

Effects of the injection levels of PMSG and HCG and injection time on the induction of superovulation of rabbits were determined. In experiment 1 adult female rabbits were intramuscularly injected with 200 IU, 50 IU per day for consecutive 2 days (100 IU) or 100 IU of PMSG, respectively. HCG were injected to all rabbits 48 hrs after the PMSG, In experiment 2 rabbits were injected 100 IU of PMSG and 100 IU HCG(48 hrs after the PMSG) at the stage A(+), B(++) and C(+++); divided according to the degree of vaginal redness. Rabbits were allowed to mate and their reproductive organs were surgically removed 48 to 50 hours after the mating. The size of ovaries, the number of follicles and hemorrhagic follicles, ovulation points and the recovery of embroyos were determined, The results are summarized as follows: 1. The number of follicles (hemorrhagic follicles) obtained in rabbits injected with 200 IU, 50 IU twice or 100 IU of PMSG was 21.5(42.2), 22.7(10.8) or 20.9(16.2), respectively. 2. The size of ovaries was not different between rabbits injected with 100 IU of PMSG at vaginal stage A, B and C. However, the number of follicles (hemorrhagic follicles) were greater in rabbits injected at stage C than in those injected at stage A or B. 3. The number of ovulation points (recovery rate of embryos) in rabbits injected with 200 IU, 50 IU twice or 100 IU of PMSG was 23.2(94%), 16.3(81%) or 22.1(86%), respectively. 4. The number of ovulation points (recovery rate of embryos) in rabbits injected with 100 IU of PMSG at vaginal stage A, B or C was 32.4(91%), 18.0(84%.) or 9.8(76%), respectively. 5. The results indicate that the single injection of 100 IU PMSG at vaginal stage A was the best in terms of the follicle quality, the ovulation points and the recovery of embryos.

황화물계 3가 크롬도금욕에서 크롬-탄소 및 크롬-탄소-인합금도금의 전착과 결정화거동

김만(M. Kim),김대영(D. Y. Kim),박상언(S. U. Park),권식철(S. C. Kwon),최용(Y. Choi) 한국표면공학회 2004 한국표면공학회지 Vol.37 No.2

Chromium-carbon (Cr-C) and chromium-carbon-phosphorus (Cr-C-P) alloy deposits using trivalent chromium sulfate baths containing potassium formate were prepared to study their current efficiency, hardness change and phase transformations behavior with heat treatment, respectively. The current efficiencies of Cr-C and Cr-C-P alloy deposits increase with increasing current density in the range of 15-35 A/dm². Carbon content of Cr-C and phosphorous of Cr-C-P layers decreases with increasing current density, whereas, the carbon content of Cr-C-P layer is almost constant with the current density. Cr-C deposit shows crystallization at 400℃ and has (Cr+Cr₂₃C?) phases at 800℃. Cr-C-P deposit shows crystallization at 600℃ and has (Cr+Cr₂₃C?+Cr₃P) phases at 800℃. The hardness of Cr-C and Cr-C-P deposits after heating treatment for one hour increase up to Hv 1640 and Hv 1540 and decrease about Hv 820 and Hv 1270 with increasing annealing temperature in the range of 400~800℃, respectively. The hardness change with annealing is due to the order of occurring of chromium crystallization, precipitation hardening effect, softening and grain growth with temperature. Less decrease of hardness of Cr-C-P deposit after annealing above 700℃ is related to continuous precipitation of Cr₂₃C? and Cr₃P phases which retard grain growth at the temperature.

농후사료 급여수준이 비거세 한우의 증체와 부위별 지방조직의 지방산 조성에 미치는 효과

송만강,김내수,정정수,최양일,원유석,정재경,최성호 ( M . K . Song,N . S . Kim,C . S . Chung,Y . I . Choi,Y . S . Won,J . K . Chung,S . H . Choi ) 한국축산학회 1998 한국축산학회지 Vol.40 No.5

The study was conducted with 63 Hanwoo bull calves of 193 days old for 19 months(up to 26 month of age) to examine the effect of feeding level of concentrate on the body weight gain, feed requirements and fatty acid composition of adipose tissues of various locations(subcutaneous, abdominal, kidney, intermuscular and intramuscular fats). The calves were allotted into 3 treatments according to the feeding level of concentrate(85, 100 and 115%), and fed concentrates of Grower(7∼10 month of age), Finisher I(11∼16 month of age), Finisher II (17∼20 month of age) and Finisher III(21∼26 month of age). The feeding levels of concentrates for the cattle of 85% and 115% were decreased or increased by 15%, respectively, up to 15 month of age based on the similar body weight to the cattle of 100%. The feeding levels of the concentrates for the cattle of 85% and 100% were continuously increased for the next 2 months, to make same levels as for the cattle of I15%, thereafter amount of concentrate were continuously increased based on the rate of body gain for all the cattle. The cattle were fed in a individual feeding system through the experimental period. The cattle were slaughtered at the ages of 6, 14, 18 and 24 month and adipose tissues were collected to analyze long chain fatty acids. Results observed from the study were summarized as follows Overall mean dry matter intake and body gain per day and feed requirements of Hanwoo bulls during the 19 months of feeding from 193 day old calves were 6.69㎏, 0.95㎏ and 7.06, respectively. Body gain of the Hanwoo bulls during experimental period was greatly affected by the feeding level of concentrate, but feed requirement was improved up to 20 month of age with the decreased feeding level of concentrate. Fatty acids of C_(16:0) C_(18:0) and C_(18:1) in the adipose tissues at various locations of Hanwoo bulls were dominated. The feeding level of concentrate did not affect the fatty acid composition except for C_(16:1) and C_(18:1) in subcutaneous fat, and C_(18:1) and C_(18:2) in intramuscular fat of the cattle that were fed at the level of 85% at the age of 14 month(P$lt;.05). No differences were observed in fatty acid composition of adipose tissues of each location for the cattle of 18 and 24 month of age among treatments. There were tendencies of greater C_(16:1) and C_(18:1) in subcutaneous and intramuscular fats while higher C_(18:0) in abdominal fat. There were also trends of greater unsaturated fatty acid compositions in subcutaneous and intramuscular fats and higher saturated fatty acids in abdominal, kidney and intermuscular fats. Percent C_(18:0) tended to be decreased while C_(16:1) C_(18:1) and C_(18:2) increased with the age of Hanwoo bulls.

한우 비육에 관한 연구 1 . Methylthiouracil 첨가 및 Estradiol 17β - Cypionate 주사가 약령 모우 비육에 미치는 효과

김창기 ( C K Kim ),이택원 ( T W Lee ),김종욱 ( J W Kim ),배대식 ( D S Bae ),오선균 ( S K Oh ),조지훈 ( C H Cho ),김법회 ( B H Kim ),김상렬 ( S Y Kim ),배신석 ( S S Bae ) 한국축산학회 1971 한국축산학회지 Vol.13 No.1

This study was performed to affirm any effects of methylthiouracil and estradiol 17β-cypionate administered to young bulls for short term fattening. Eighteen bulls of Korean native breed, approximately 1.5 to 2 years of age and 260㎏ to 360㎏ in weight, were used in this study. All bulls had received a basal ration of soiling corn and concentrate made up of 55% grains, 40% brans and 5% others, in a period of 40 days. Bulls were divided into six groups as follows: group C was not treated, group M-2 received 2g of methylthiouracil per day, group M-3 received 3g of methylthiouracil per day, group EM-0 was injected intramusculary with 25㎎ of estradiol 17β-cypionate in the neck region 10 days after the beginning of the fattening period, group EM-2 was injected with estradiol 17β-cypionate as above mentioned and simultaneously received 2g of methylthiouracil per day, and group EM-3 was injected with estradiol 17β-cypionate as above mentioned and simultaneously received 3g of methylthiouracil per day. The results obtained were summarized as follows. 1. The average daily gain was for group C: 0.83㎏, group M-2: 1.07㎏, group M-3: 1.40㎏, group EM-0, 0.93㎏, group EM-2: 0.95㎏, and group EM-3: 1.18㎏. The M-3 group gained significantly(P$lt;0.05) more weight than C and EM-0 group. There were no significant differences in the average daily gain between the groups injected with estradiol 17β-eypionate and the control group. 2. The average daily concentrate intake was as follows: group C: 5.47㎏, group M-2: 5.00㎏, group M-3: 4.52㎏, group EM-0: 5.21㎏, group EM-2: 4.35㎏, and group EM-3: 4.61㎏. The consumption of concentrate was decreased by 17% in the M-3 group compared with the C group. There was no significant difference in the soiling corn intake among these groups. 3. Feed consumed for 1㎏ gain were decreased by the supplementation of methylthiouracil. The consumption of DCP for 1㎏ gain was in group C: 0.82㎏, group M-2: 0.59㎏, group M-3: 0.41㎏, group EM-0: 0.70㎏, group EM-2: 0.59㎏, and group EM-3: 0.50㎏. The amounts of TDN required were; group C: 6.57㎏, group M-2: 4.76㎏, group M-3: 3.39㎏, group EM-0: 5.67㎏, group EM-Z: 4.87㎏, and group EM-3: 4.08㎏. The consumption of DCP and TDN for 1㎏ gain in the M-3 group was about a half of that in the C group. 4. There was not any significant difference in the increase in body measurements among the various groups. 5. The average margins in the fattening period of 40 days were for group C: 2,950won, group M-2: 5,327won, group M-3: 9,158won, group EM-0: 3,310won, group EM-2: 3,623won, and group EM-3: 5,575won. The margin of group M-3 was about three times higher than that of group C. In short, this experiment demonstrated that methylthiouracil when fed to young native Korean bulls at the proper level 40 days before slaughter would bring a noticeable effect on weight gain, feed efficiency and economic advantage. There were no advantages from the simultaneous injecting estradiol 17β-cypionate with methylthiouracil. The proper supplementation level of methylthiouracil would appear to be 3g per head per day in this experiment.

Microbial Influence on Soil Properties and Pollutant Reduction in a Horizontal Subsurface Flow Constructed Wetland Treating Urban Runoff

Chiny. C. Vispo,Miguel Enrico L. Robles,오유경(Yugyeong Oh),Haque Md Tashdedul,김이형(Lee Hyung Kim) 한국습지학회 2024 한국습지학회지 Vol.26 No.2

인공습지는(CW)는 침투, 흡착, 저류, 식물과 미생물의 증발산 등과 같은 수문학적 및 생태학적 기작에 의하여 오염물질 제거, 탄소흡수 및 저장, 생물다양성 향상 등의 생태계서비스를 제공한다. 본 연구는 수평지하흐름 인공습지(HSSF CW)의 미생물 군집과 토양의 물리·화학적 특성 및 처리효율의 상관관계를 분석하기 위하여 수행되었다. 연구를 위한 모니터링은 강우시 수질특성, 토양특성, 미생물 분석이 수행되었다. 따뜻한 계절(>15°C) 에서 TSS, COD, TN, TP 및 중금속(Fe, Zn, Cd) 제거효율이33~74% 범위로 나타났다. 그러나 추운 계절(≤15°C)에서 TOC 35%로 가장 높은 제거 효율이 나타났다. 인공습지 내 토양은 인근에서 채취한 토양의 토양유기탄소(SOC) 함량보다 3.3배 더 높은 함량을 가지고 있는 것으로 나타났다. 유입부와 유출부의 탄소(C), 질소(N) 및 인(P)의 화학양론비(C:N:P)는 각각 120:1.5:1 및 135.2:0.4:1로 나타났으며, 탄소에 비해 질소와 인의 비율이 매우 낮아 미생물 성장에 문제가 발생될 수 있다. 미생물 분석에서는 생물다양성 지수를 통해 미생물 군집의 풍부도, 다양성, 균질성 및 균일성이 따뜻한 계절이 추운 계절에 비해 높게 나타났다. 인공습지의 강우유출수 오염물질 중 질소고정 미생물인 Proteobacteria, Actinobacteria, Acidobacteria, Bacteroidetes가 우점종으로 미생물 생장을 촉진하는 것으로 평가되었는데 이는 특정 토양특성 및 유입수 특성이 미생물 풍부도와 밀접한 관련이 있음을 의미한다. Constructed wetlands (CWs) deliver a range of ecosystem services, including the removal of contaminants, sequestration and storage of carbon, and enhancement of biodiversity. These services are facilitated through hydrological and ecological processes such as infiltration, adsorption, water retention, and evapotranspiration by plants and microorganisms. This study investigated the correlations between microbial populations, soil physicochemical properties, and treatment efficiency in a horizontal subsurface flow constructed wetland (HSSF CW) treating runoff from roads and parking lots. The methods employed included storm event monitoring, water quality analysis, soil sampling, soil quality parameter analysis, and microbial analysis. The facility achieved its highest pollutant removal efficiencies during the warm season (>15°C), with rates ranging from 33% to 74% for TSS, COD, TN, TP, and specific heavy metals including Fe, Zn, and Cd. Meanwhile, the highest removal efficiency was 35% for TOC during the cold season (≤15°C). These high removal rates can be attributed to sedimentation, adsorption, precipitation, plant uptake, and microbial transformations within the CW. Soil analysis revealed that the soil from HSSF CW had a soil organic carbon content 3.3 times higher than that of soil collected from a nearby landscape. Stoichiometric rtios of carbon (C), nitrogen (N), and phosphorus (P) in the inflow and outflow were recorded as C:N:P of 120:1.5:1 and 135.2:0.4:1, respectively, indicating an extremely low proportion of N and P compared to C, which may challenge microbial remediation efficiency. Additionally, microbial analyses indicated that the warm season was more conducive to microorganism growth, with higher abundance, richness, diversity, homogeneity, and evenness of the microbial community, as manifested in the biodiversity indices, compared to the cold season. Pollutants in stormwater runoff entering the HSSF CW fostered microbial growth, particularly for dominant phyla such as Proteobacteria, Actinobacteria, Acidobacteria, and Bacteroidetes, which have shown moderate to strong correlations with specific soil properties and changes in influent-effluent concentrations of water quality parameters.

BT40용 A.T.C Test Bench 개발에 관한 연구

김재현(J.H. Kim),이춘만(C.M. Lee),이문재(M.J. Lee),김광선(K.S. Kim),최준영(J.Y. Choi) 한국생산제조학회 2010 한국공작기계학회 추계학술대회논문집 Vol.2010 No.-

This paper is on the development of A.T.C Test Bench for BT40. A Test Bench is consist of hardware part, electronic device part and software part. It is designed to test vibration status and degree of precise position of A.T.C magazine when operating as well as magazine's operation itself. A.T.C Test Bench for BT40 can check A.T.C's basic performance and we can cassure reliability and stability through this tool.

2004년 전국 복강경 위 수술 현황

김형곤,김곤홍,김동헌,김민찬,김병식,김영우,김용일,김용호,김욱,김원우,김진조,김태봉,류성엽,Kim, H.H.,Kim, K.H.,Kim, D.H.,Kim, M.C.,Kim, B.S.,Kim, Y.W.,Kim, Y.I.,Kim, Y.H.,Kim, W.,Kim, W.W.,Kim, J.J.,Kim, T.B.,Ryu, S.Y. 대한위암학회 2005 대한위암학회지 Vol.5 No.4

대한복강경위장관연구회가 2004년 전국에서 시행된 복강경 위 수술의 현황을 조사하였다. 모두 36개의 기관으로부터 38명의 외과의가 설문에 응답하였다. 2004년 한 해 동안 시행된 복강경 위 수술은 총 1,089예였고 1995년부터 2004년까지 시행된 복강경 위 수술을 누적하면 모두 2,386예였다. 2004년에 위선암 환자에서 시행된 복강경 위 수술은 2003년보다 약 2배 많은 754예였다. 위선암에 대한 근치적 위절제술인 복강경보조위아전절제술 및 복강경보조위전절제술은 2001년도를 전환점으로 급속히 증가하였다(2001년 55예, 2002년 150예, 2003년 364예, 2004년 738예). 특히 복강경보조위전절제술은 작년에 폭발적 인 증가를 보였다. (2003년 20예, 2004년 112예). 그러나 복강경보조유문부보존위절제술 및 복강경보조근위부위절제술과 같은 복강경보조기능보존위절제술은 작년 각각 1예씩 시행되어 아직 보편화되지 않았다. 위 점막하종양에 시행된 복강경위쐐기절제술은 142예였다. Hand-assisted laparoscopic surgery는 2001년 39예, 2002년 55예, 2003년 49예가 시행되었으나 2004년에는 단 5예만 시행되어 급격한 감소를 보였다. 고도비만수술은 2003년도에 시작되어 2004년에는 49예로 증가하였다. 위선 암에서 복강경위수술의 적응증에 대한 견해로서 19명이 조기위암에서 시행한다고 하였고 7명은 적응증을 T2N0까지 넓히고 있었다. 앞으로 보험문제가 해결이 되고 장기 성적이 나온다면 위선암에 대한 복강경 위 수술은 널리 보편화될 것이다. The Korean laparoscopic Gastrointestinal Surgery Study Group made a survey of laparoscopic gastric surgeries which were performed in Korea during 2004. Thirty-eight surgeons from 36 Institutions responded to the questionnaires. One thousand eighty-nine laparoscopic gastric operations were performed during 2004. The cumulative number from 1995 to 2004 was about 2,386. Seven hundred fifty-four operations for a gastric adenocarcinoma were performed during 2004 which is almost two times the number performed during 2003. Laparoscopic radical procedures, such as a laparoscopy-assisted distal gastrectomy or total gastrectomy (LADG and LATG) have increased rapidly since 2001 (55 cases in 2001, 150 cases in 2002, 364 cases in 2003 and 738 cases in 2004). Especially, laparoscopic total gastrectomies were explosively adopted last year (20 cases in 2003 and 112 cases in 2004). However, laparoscopic function-preserving gastrectomies, which included one laparoscopy-assisted pylorus-preserving gastrectomy and laparoscopy-assisted proximal gastrectomy, are rarely performed at this time. One hundred forty-two wedge resections for a gastric submucosal tumor were performed during 2004. Hand-assisted laparoscopic surgery (HALS) was performed in 39 cases in 2001, 55 in 2002, and 49 in 2003; however, only 5 such surgeries were performed during 2004. In 2003, laparoscopic bariatric surgery began, and during 2004, 49 operations were performed. In terms of indications of laparoscopic gastric surgery for adenocarcinoma, 19 surgeons performed a LADG only for a T1 lesion, and 7 surgeons extended their indications to T2N0 lesions. In the near future, laparoscopic procedures for gastric cancer will be widely adopted in Korea if the medical-insurance obstacle is overcome, and the long-term survival results are verified.

제주재래돼지와 듀록 참조축군에서 Melanocortin 4 Receptor (MC4R) 유전자형과 지방산 조성간의 관련성 분석

강용준(Yong-Jun Kang),김상금(Sang-Geum Kim),김수연(Su-Yeon Kim),신문철(Moon-Cheol Shin),우제훈(Jae-Hoon Woo),김남영(Nam-Young Kim),신상민(Sang-Min Shin),최재영(Jae-Young Choi),유지현(Ji-Hyun Yoo),박남건(Nam-Geon Park),양병철(Byoung-C 한국생명과학회 2020 생명과학회지 Vol.30 No.1

본 연구에서는 제주재래돼지와 듀록 품종 사이에서 생산된 F₂ 참조축군에서 melanocortin-4-receptor (MC4R) 유전자형과 지방산 조성간의 관련성을 연구하였다. 전체 290 여두의 F₂ 자손을 이용하여 14개의 지방산 조성을 측정하였다. Taq Ⅰ PCR-RFLP 방법을 이용하여 MC4R c.1426A>G (p.Asp298Asn)의 단일염기다형성(single nucleotide polymorphism, SNP)을 확인하였다. MC4R 세 가지 유전자형(AA, AB, BB)이 모두 발견되었고, 그 빈도는 각각 0.299, 0.542, 0.159로 확인되었다. AA 유전자형을 가진 개체에서 palmitic acid (C16:0, p<0.05), stearic acid (C18:0, p<0.01), eicosenoic acid (C20:1n9, p<0.05), saturated fatty acid (SFA, p<0.01) 함량이 GG 유전자형을 가진 개체보다 더 높은 것으로 확인되었다. 반면에 GG 유전자형을 가진 개체는 linoleic acid (C18:2n6, p<0.001), linolenic acid (C18:3n3, p<0.001), linolenic acid (C18:3n6, p<0.001), arachidonic acid (C20:4n6, p<0.001)과 같은 불포화지방산(unsaturated fatty acid) 함량이 AA 유전자형을 가진 개체보다 더 높은 것을 확인하였다. 제주재래돼지와 듀록 품종 사이에서 생산된 F₂ 참조축군에서 MC4R GG 유전자형이 포화지방산은 낮추고, 불포화지방산은 높이는 것으로 확인되었다. 본 연구 결과 MC4R의 유전적 다형성이 듀록과 제주재래돼지 교배 프로그램에서 육질향상과, 고기내의 지방산 함량을 조절할 수 있는 유전적 표지 인자로 활용될 수 있을 것이라 사료된다. This study was conducted to examine association between melanocortin-4-receptor (MC4R) genotypes and fatty acid (FA) composition in an F₂ intercross between Duroc and Jeju (South Korea) Native pigs (JNP). Fourteen FA composition traits were measured in more than 290 F₂ progeny population produced between Duroc and JNP. All experimental pigs were successfully genotyped for the MC4R c.1426A>G (p.Asp298Asn) single nucleotide polymorphism (SNP) by using Taq Ⅰ PCR-RFLP methods. We detected three MC4R genotypes, AA, AG, and GG with 0.299, 0.542, and 0.159 genotype frequencies, respectively. The MC4R AA genotype animals showed higher levels in palmitic acid (C16:0, p<0.05), stearic acid (C18:0, p<0.01), eicosenoic acid (C20:1n9, p<0.05), saturated fatty acid (SFA, p<0.01) than GG homozygotes, respectively. Whereas MC4R GG genotype showed higher values in linoleic acid (C18:2n6, p<0.001), linolenic acid (C18:3n3, p<0.001), linolenic acid (C18:3n6, p<0.001), arachidonic acid (C20:4n6, p<0.001) and unsaturated fatty acid (USFA, p<0.01) than AA pigs, respectively. The MC4R GG genotype was associated with increasing USFA and decreasing SFA in the F₂ progeny population produced between Duroc and JNP. Our finding suggests that the MC4R polymorphisms can be used as a valuable genetic marker for Duroc and JNP breeding programs to improve meat quality and to control FA compositions.

담관낭종 -대한소아외과학회회원 대상 전국조사-

최금자,김대연,김상윤,김성철,김신곤,김우기,김인구,김재억,김재천,김해영,김홍주,박귀원,박우현,박진영,백홍규,서정민,송영택,오수명,유수영,이두선,이명덕,이석구,이성철,박영식,이태훈,정상영,Choi, Kum-Ja,Kim, D.Y.,Kim, S.Y.,Kim, S.C.,Kim, S.K.,Kim, W.K.,Kim, I.K.,Kim, J.E.,Kim, J.C.,Kim 대한소아외과학회 2003 소아외과 Vol.9 No.1

본 조사 결과는 32개 병원의 39명의 회원에 의해 수술받은 환자 348명의 기록과 회원 37명의 설문 응답자를 분석한 것으로 많은 수의 기록지가 내용이 불충분하거나 일치되지 않은 기술로 인해 자료로서의 한계가 있었다. 특히 췌담관합류 이상에 대한 기록 중 약 절반이 미상으로 기록된 것에서 알 수 있드시 자료가 매우 미흡하였고, 담관낭종의 유형을 정하는 것 예후 인자 및 산 전 진단된 담관낭종의 수술 적기등에 대하여도 회원마다 견해 차이가 있으나 심도있는 토론이 이루어지지 않았다. 따라서 이 결과를 외국의 통계 분석과 비교하는 것 보다는 회원들의 향 후 진료와 연구에 참고가 될 수 있다는 것에 의미를 두고자 하며, 회원들이 동일한 등록지를 작성하는 전향적 연구로 우리나라 담관낭종에 대한 분류, 췌담관 합류이상, 예후 인자들에 대한 재 논의의 출발점이 되기를 기대한다. A nationwide survey on choledochal cyst was undertaken among 39 members of the Korean Association of Pediatric Surgeons. The members were required to complete a questionnaire and the case registration form for each patient during the five year period of 1997 to 2001. Three hundred and forty eight patients were registered from 32 institutions. The average number of patients per surgeon was one to two every year. The male to female ratio was 1:3.4. The age of patients on diagnosis was $49.0{\pm}44.4$ months. The geographic distribution was 34.8% in Seoul and Kyoungki-do, 33.3% in Kyoungsang-do, 17.9% in Cholla-do, and 8.5% in Choongchung-do, in order of frequency. The three common clinical presentations were abdominal pain (63.8%), vomiting (35.3%), and jaundice (29.1%). Only seven patients (2%) presented with classic triad, and 25 patients were diagnosed by antenatal ultrasonographic examination. According to the Todani Classification, 238 patients (7l.3%) were type 1, 3 (0.9%) type 11, and 93 (27.8%) type IV. At the time of the operation, three important associated conditions were choledocholithiasis in 45 patients (15.1%), liver fibrosis (Grade 1-4) in 35, and previous operative procedure for biliary diseases in 10. Associated anomalies were observed in 13 patients (3.8%). Three hundred thirty nine (98.8%) of 343 lesions were treated by Cyst excision and Roux-Y hepaticoiejunostomy. One hundred seventy-six patients had an anomalous arrangement of the pancreatobiliary ductal system (APBD): APBD was not in 92 patients, biliary duct joined to the pancreatic duct in 51, and pancreatic duct joined to the biliary duct in 26. There were 8.5% early, and 7.7% late phase operative complications. The major complications were bleeding, anastomotic leakage, and acute pancreatitis. The combination of acute abdomen and choledochal cyst may suggest spontaneous rupture. Because of the development of late intrahepatic bile duct stones, long term follow up after cyst excision and hepaticojejunostomy is required. The optimal time of surgical intervention should also be considered in the situation of routine use of antenatal ultrasonographic examination. This is the first review of the choledochal cyst in Korea and provides baseline data for future comparisons.