양수발전소 과도 운전상태 적용 조기경보 상태지수 개발 방법론

이병오(Byoung-Oh Lee),예송해(Songhae Ye),전이슬(I-seul Jeon),최현식(Hyeon-Sik Choi) 대한기계학회 2023 대한기계학회 춘추학술대회 Vol.2023 No.3

만기 임신의 저위험 산모군에서 양수과소증이 주산기 예후에 미치는 영향과 임상적 의의

안현영 ( Hyun Young Ahn ),김연희 ( Yeon Hee Kim ),김아리 ( A Ri Kim ),서미원 ( Mi Won Seo ),김옥경 ( Ok Kyung Kim ),이귀세라 ( Guisera Lee ),김사진 ( Sa Jin Kim ),신종철 ( Jong Chul Shin ) 대한산부인과학회 2007 Obstetrics & Gynecology Science Vol.50 No.12

Objective: The purpose of this study was to assess the effect of the isolated oligohydramnios on the perinatal outcome in uncomplicated term pregnancies. Methods: We used data from Jan 2002 to Dec 2005 in all uncomplicated pregnancies between 37 and 41weeks and 6 days of gestation with a singleton fetus, underwent monitoring with serial determination of AFI. Oligohydramnios was defined by ultrasonographic determination of AFI ≤5 cm. Exclusion criteria were PROM, maternal medical complications and fetal anomalies detected by prenatal ultrasound. We investigated the mode of delivery, birth weight, birth weight < 10th percentile, 1 and 5 min Apgar score, umbilical cord pH and base excess, and meconium stained amniotic fluid (MSAF). We also assessed the predictive value of obstetric factors associated with adverse perinatal outcome. We used statistics analysis by Chi-square test, independent-samples T test using SPSS 14.0 V. Results: 2,491 patients met our inclusion criteria. Oligohydramnios was diagnosed in 8.63% (215/2,491). There was significantly difference in cesarean section for fetal distress between those with oligohydramnios vs. normal AFI (43.8% vs.4.1%). Patients with oligohydramnios had significantly lower SGA (15.3% vs. 5.7%), lower Apgar score at 1 min<7 (7.9% vs. 3.3%), and higher rate of MSAF (31.2% vs. 18.4%) than those with normal AFI. There were musculoskeletal abnormalities in 10/215 (4.6%) and urogenital abnomralites in 53/215 (24.6%). Conclusion: Isolated oligohydramnios in uncomplicated term pregnancies is associated with an increased adverse perinatal outcome. Nulliparity, advanced maternal age, MSAF, SGA, and lower BPP were significantly associated with the adverse perinatal outcomes.

임신 중기 양수와 산모 혈청 leptin 농도: 임신 주수, 태아 성별, 초음파 측정 태아 체중, 산모 체질량 지수와의 상관관계

임영구(Young Koo Lim),송은섭(Eun Seop Song),송경은(Kyung Eun Song),임문환(Mun Hwan Lim),이병익(Byoung Ick Lee),김종화(Jong Wha Kim),최원식(Won Sick Choe) 대한산부인과학회 1999 Obstetrics & Gynecology Science Vol.42 No.12

Objectives: Leptin is a 16-kD protein encoded by the ob/ob gene and represent the amount of body fat. In pregnancy, it is thought to act in intrauterine fetal growth and energy metabolism. In this study, we investigated the effect of gestational age, fetal sex, maternal body mass index (BMI), and fetal weight estimated by ultrasound on amniotic fluid and maternal serum leptin levels at mid-trimester, respectively. Methods: Amniotic fluid and maternal blood sampling were collected from women who was performed for genetic amniocentesis at mid-trimester (n = 26). Leptin concentrations were measured by a specific radioimmunoassay (RIA) employing human recombinant leptin. Mean gestational age was 18.19±1.77 weeks. Mean maternal BMI was 23.83 ±5.12kg/m2. Male fetus was 10, and female 16. Mean fetal weight estimated by ultrasound was 254.42±83.80gm. Results: Mean maternal leptin level( 12.49±4.46 ng/mL) was significantly higher than mean amniotic leptin level(5.06±3.20 ng/mL)( p = 0.0001) at mid-trimester. But there was no significant correlationship between maternal and amniotic leptin levels( p = 0.1376). Maternal leptin concentrations at mid-trimester were correlated positively with maternal BMI(y = 2.24 + 0.43 x, R2 = 0.494, p = 0.0103). In contrast, leptin levels in amniotic fluid did not correlate with maternal leptin levels, gestational age, fetal sex, maternal BMI, and fetal weight estimated by ultrasound respectively. Conclusion: Maternal leptin level was higher than amniotic leptin level and could represent maternal fat mass. It was suggested that amniotic leptin level was not associated with several factors such as maternal, fetal, and amniotic factors.

저위험 산모군에서 주산기 예후의 예측인자로서 양수과소증의 의의

민주영 ( Joo Young Min ),오민정 ( Min Jeung Oh ),조금준 ( Geun Joon Cho ),이재관 ( Jae Kwan Lee ),이경주 ( Kyung Ju Lee ),김해중 ( Hai Joong Kim ),허준용 ( Jun Young Hur ),서호석 ( Ho Suk Saw ),박용균 ( Yong Kyun Park ) 대한산부인과학회 2004 Obstetrics & Gynecology Science Vol.47 No.9

Objective : The aim of our study was to assess whether isolated oligohydramnios is associated with adverse perinatal outcomes in low-risk term pregnancy. Methods : Women delivered between March 2001 and July 2003, who underwent ultrasonography from 37 to

만삭전 조기양막파열에서 분만 잠복기의 예측지표로서 입원시 측정한 양수지수의 유용성

양순하(Soon Ha Yang),박선혜(Seon Hye Park),오성희(Sung Hee Oh),황종대(Jong Dae Whang),노정래(Cheong Rae Roh) 대한산부인과학회 1999 Obstetrics & Gynecology Science Vol.42 No.12

Objectives: The purpose of this study was to determine the clinical significance of residual amniotic fluid volume, as measured by the amniotic fluid index(AFI), on the prediction of latency period and perinatal outcomes in patients with preterm premature rupture of the membranes(PPROM). Methods: Study population consisted of 103 singleton pregnancies with PPROM between 24 and 34 weeks' gestation. Amniotic fluid index was determined using transabdominal ultrasound at admission. Latency period was defined as time interval in hours between admission and delivery. All medical records of mothers and neonates were reviewed. Spearman's rho rank correlation, receiver-operator characteristic(ROC) curve analysis, survival analysis and Cox's proportional hazard model were used for statistical analysis. Results: There was a statistically significant correlation between latency period and AFI at admission. ROC curve analysis showed that AFI at admission had a significant predictive value in the prediction of latency period < 48 hours. Survival analysis demonstrated that AFI < 5.0 was strongly associated with the likelihood of shorter latency period, Cox's proportional hazard model indicated that AFI < 5.0 was a significant independent predictor for the occurrence of latency period < 48 hours even after adjustment of other independent variables. The patients with AFI < 5.0 had a higher rate of cesarean section due to fetal distress than those with AFI > 5.0 but the incidence of chorioamnionitis was not significantly different between two groups. Comparing the perinatal mortality and neonatal morbidity including infectious morbidity between the neonates born to mothers with AFI < 5.0 and those with AFI > 5.0, there was no significance after adjustment of gestational age at birth. Conclusion: AFI at admission has a significant correlation with latency period and predictive value in prediction of latency period in the patients with PPROM. AFI < 5.0 is a independent predictor for the shorter latency period.

單一핀을 가진 水平管에서의 自然對流 熱傳達

정한식,권순석 대한기계학회 1987 대한기계학회논문집 Vol.11 No.2

본 논문에서는 수평관 내부의 체적평균온도를 가진유체의 난류강제대류에서 열전달이 일어나는 경우에 대하여 핀이 없는 수평전도관, 하향 핀이 부착된 수평전도 관 그리고 상향 핀이 부착된 수평전도관의 열전달 특성을 수치계산으로 연구하고 Mach -Zehnder 간섭계를 이용하여 실험하였고 수치해석과 실험결과를 비교하여 타당성을 확 인하였다. An numerical and experimental study has been performed on natural convection heat transfer from a horizontal heat exchanger tube with a fin. At s bare tube, by increasing $C_{T}$ (tube conduction parameter), mean Nusselt number and outer wall temperature are apparently increased at $C_{T}$.leq.300, slightly increased at $C_{T}$>300 and they can be represented in an exponential function of $C_{T}$. Natural convection heat transfer characteristics for the tube with a fin at given Rayleigh number are well agreed by those for an isothermal cylinder at a modified Rayleigh number. The local fin Nusselt number of the tube with a downward fin is much higher than that of the tube with an upward fin. The comparisons between numerical and experimental results showed good agreement.reement.

만삭 단태임신의 분만일 예측과 관련된 초음파 인자

김광준 ( Gwang Jun Kim ),이은실 ( Eun Sil Lee ),이우석 ( Woo Seok Lee ),이상훈 ( Sang Hoon Lee ),장영진 ( Young Jin Jang ),김동호 ( Dong Ho Kim ) 대한산부인과학회 2006 Obstetrics & Gynecology Science Vol.49 No.7

Objective: The aim of this study was to find out the relating factors with the actual delivery day in term singleton pregnancy. Methods: The 52 patients with singleton gestation were visited weekly and measured for their lower uterine segment (LUS) thickness, cervical length and cervical gland thickness by transvaginal ultrasonography and for amnionic fluid index (AFI) by transabdominal ultrasonography from 36 weeks of gestation until birth. Regression analysis was used to find out the relevance between these factors and remaining days to birth. Resullts: There was a significant relationship between cervical length and remaining days to birth in term pregnancy, which could be described as a mathematical equation (remaining days for delivery=6.12+0.24×cervical length (㎜) r=0.29, p<0.01). However, no relationship was found between factors such as LUS, AFI, and cervical gland thickness and remaining days to birth. Conclusion: Our results suggest that the actual delivery day in term singleton pregnancy might be predicted with cervical length.

자궁적출술의 수술적 접근방법으로 복식에서 질식경로로의 변화에 관한 연구 : 1990년부터 1997년까지 질식자궁적출술 3408예의 임상 경험적 연구

강정배(Jung Bae Kang),정태범(Tae Bum Jung),김홍배(Hong Bae Kim),이근영(Geun Young Lee),강성원(Sung Won Kang) 대한산부인과학회 2001 Obstetrics & Gynecology Science Vol.44 No.1

Objective : The purpose of our study evaluate to assess the feasibility and safety of performing vaginal hysterectomy on our experience. Methods : Between 1990 year and 1997 year, 3408 women underwent vaginal hysterectomy without laparoscopic assistance at Hallym University Hospital in Korea. All hysterectomies(abdominal & vaginal) were reviewed and these were compared with all hysterectomy cases from most recent year available for complete analysis. Result : 1. In 1990 yrs ∼ 1997 yrs, vaginal hysterectomies compromised 51%(vaginal hysterectomy〔below VH〕: 268 / total abdominal hysterectomy〔below TAH〕: 258 ; 1990), 55%(VH: 254 / TAH: 212 ; 1991), 60%(VH: 346 / TAH: 227 ; 1992), 64%(VH: 341 / TAH: 190 ; 1993), 72%(VH: 434 / TAH: 168 ; 1994), 75%(VH: 489 / TAH: 156 ; 1995), 76.%(VH: 632 / TAH: 196 ; 1996), 78%(VH: 657 / TAH: 190 ; 1997), a high increased rate of vaginal hysterectomy significantly. 2. The average age of patients was 41.9± 8.18(26∼84) years old and 25 nullipara and 274 primiparas and 3109 multiparas. The mean parity was 2.74±0.36. 3. The common surgical indications were uterine myoma(53.9%), prolapse of uteri(23.3%), CIN II-III or microinvasive cervical cancer(6.5%), others(16.3%) 4. The average time of operation(hysterectomy and colporrhaphy) was 78.3± 14.2 min(40∼230). 5. The average weight of uterus was 166.5± 111.4 gm(60∼1130 gm), 34.0% was done morcellation. 6. 5.7% of operated women had previous abdominal operaton (without tubal ligation). 7. The common associated procedures were posterior colporrhaphy(47.4%), anteroposterior colporrhaphy(45.6%), adnexectomy(4.9%), other(2.1%). 8. The mean blood loss was 280± 104.4 ml and 12.4% of operated women were need of transfusion. 9. The minor complication rate was 10.6% e.g. urinary retention(5.3%-179cases), abdominal bleeding (including conversion TAH) (0.3%-9cases), pelvic hematoma(0.3%-11cases), post operation fever(2.8%-94cases), mortality cases none. 10. The mean hospital days were 7 days(4∼20) Conclusion : In our experience the following conclusions have been reached that vaginal hysterectomy is usually well tolerated by most women, a safe operation with few complications and without notable blood loss and without the need of expensive laparoscopic equipment. The incidence of vaginal hysterectomy is characterized by pronounced fluctuations suggested that no valid general guidelines have yet been established for the indication via vagina of surgical treatment. The incidence of vaginal hysterectomy correlates with the experience of individual surgeon strongly. Vaginal hysterectomy remains the method of choice for removal of the uterus in the absence of absolute contraindication.

태아안녕검사에 있어서 Rapid Biophysical Profile 의 유용성

김학준(Hag Joon Kim),고민석(Min Seok Koh),임병도(Byeong Do Lim),여정언(Jung Eun Yeo),정의식(Eul Sik Jung) 대한산부인과학회 2001 Obstetrics & Gynecology Science Vol.44 No.6

Object : The nonstress test(NST) and complete biophysical profile(BPP) were compared with the rapid biophysical profile(BPP) in order to evaluate the efficacy of the rapid BPP, namely, the combination of amniotic fluid index(AFI) and sound-provoked fetal movement(SPFM) detected by ultrasound, in predicting intrapartum fetal distress in high-risk pregnancies. Study design : From JAN 9th 2000, through JAN 5th 2001, the prospective study of diagnostic tests was conducted on a total of 91 high-risk singleton pregnancies, undergoing antepartum assessment both the standard NST and the new rapid BPP(including other indices of complete BPP). The diagnostic indices of the NST, rapid BPP and complete BPP were calculated in term of predicting intrapartum fetal distress. Result : The sensitivity, specificity, negative predictive value, and positive predictive value of NST were 50.00, 94.81, 96.05, and 42.86% respectively, and those of rapid BPP were 75.00, 98.53, 98.53, and 75.00%, and those of complete BPP were 83.33, 98.72, 98.72, and 83.33%, as well. In addition, the efficiency of NST, rapid BPP, and complete BPP were 91.57%, 97.22% and 97.62% respectively. Conclusions : The rapid BPP is an effective and reliable predictor of intrapartum fetal distress with high-risk pregnancies. Moreover, it may be inexpensive and less time-consuming method.

인공지능 모델을 활용한 실시간 수질평가지수 예측

김수빈,김경태,이재성 한국해양환경·에너지학회 2023 한국해양환경·에너지학회지 Vol.26 No.1

현재 해양수산부에서 연안 오염우심해역의 해양환경을 상시 측정하기 위해 해양수질자동측정망 자료를 제공하고 있다. 아울러 우리나라는 해양환경을 직관적으로 평가하기 위하여 수질평가지수(water quality index, WQI)를 사용하고 있다. 하지만, 해양환경측정망 자료는 WQI를 제공하고 있으나 해양수질자동측정망 자료는 WQI를 계산하기 위한 수질 자료가 충분하지 않다. 이 연구는 실시간으로 수질 변화를 평가하기 위해서 해양환경측정망 자료를 학습한 인공지능(artificial intelligence, AI) 모델(model)을 이용하여 보정(calibration)된 수질자동측정망 자료의 WQI를 예측하고자 한다. 특별관리해역의 수질자동측정망 자료 중 결측치(missing value)가 비교적 적은 부산수영, 광양적량, 마산삼귀, 인천송도, 시화조력, 시화반월 측정소 자료를 활용하였다. 보정을 위해 수질자동측정소와 가장 인접한 해역별 정점의 해양환경즉정망 자료를 활용하였다. Cook의 거리(Cook’s distance) 비교로 이상치를 제거하고 선형회귀(linear regression)를 통해 해양환경측정망과 동일한 조사 시간의 수질자동측정망 자료 중 결정계수(coefficient of determination)값이 큰 변수의 자료만을 보정하였다. 해양환경측정망 자료를 훈련자료(training datasets)로 사용하고 보정된 수질자동측정망 자료를 검증자료(test datasets)를 사용하여 다양한 알고리즘(algorithm)(MLR, SVR, XGBR, ETR, ANN, ELM, NFN, ANFIS, GANN)으로 학습한 모델의 예측 성능을 평균제곱근오차(root mean square error, RMSE), 평균절대오차(mean absolute error, MAE)로 평가하였다. 평가 결과 각 해역별로 최적 알고리즘과 예측성능은 상이하였고 수질이 나쁜 경우(WQI가 클수록) 예측성능이 나쁘고 일관성이 부족하였다. 자료와 보정의 품질을 향상시킨다면 실시간으로 수질자동측정망 자료의 WQI를 정확히 예측하여 수질오염 경보와 지속가능한 해양환경관리가 가능할 것이다.