• 대한수의학회지
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• 제29권4호
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• pp.589-599
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• 1989

A total of 13 synchronized dairy cattle(Holstein) were used to determine pregnancy rates in relation to plasma progesterone, estradiol-$17{\beta}$ levels and serum chemical values on the day of last $PGF_{2{\alpha}}$ injection and day of frozen/thawed bovine embryo transfer. The pregnancy rate of recipients with 1.0~4.0ng/ml of progesterone levels at the day of last $PGF_{2{\alpha}}$ injection was higher than that of recipients with below 1.0ng/ml or above 4.0ng/ml of progesterone levels. On the day of transfer, optimal progesterone levels were between 1.0ng/ml and 4.0ng/ml coinciding with a pregnancy rate of 88.9%. Pregnancy rate decreased when progesterone levels were below 1.0ng/ml(33.3%) or above 4.0ng/ml(0%). Corpus luteum grade did not affect pregnancy rate and this result revealed that manual palpation of corpus luteum was not valid criterion of corpus luteum function. Progesterone levels as well as pregnancy rate did not significantly differ whether the corpus luteum was on the right($1.62{\pm}1.33ng/ml$; 63.5%) or left ovary($1.99{\pm}0.61ng/ml$; 85.0%). Estradiol-$17{\beta}$ levels were not significantly different between pregnant and nonpregnant recipients, but estradiol-$17{\beta}$ levels($82.2{\pm}13.5$ VS. $72.3{\pm}10.1pg/ml$) were higher at below 1.0ng/ml of progesterone, and pregnancy rates(33.3 VS. 80%) tended to be lower than above 1.0ng/ml of progesterone. Total cholesterol levels on the day of last $PGF_{2{\alpha}}$ injection and day of transfer did not affect pregnancy rate. Calcium and inorganic phoshorus levels belonged to normal range in most of the recipients. These range did not affect pregnancy rate. In reviewing above results, plasma progesterone levels(1.0~4.0ng/ml) at the time of transfer are diagnostic value for screening recipients prior to transfer of frozen/thawed bovine embryos.

• Asian Pacific Journal of Cancer Prevention
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• 제17권1호
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• pp.125-129
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• 2016

Background: Patients with differentiated thyroid cancers (DTC) who receive radioactive iodine-131 (RAI) are released from isolation when their dose rate is below the regulatory requirements. The purpose of this study was establish predicting factors for early release from the isolation facility after RAI administration in patients with DTC. Materials and Methods: This was a prospective study which included 96 (58 females and 38 males) patients with DTC who had received RAI from April 2013 till August 2015. The study was duly approved by the ethical committee of the institute. Patients who had complete information of primary tumor size (PTS), serum TSH, stimulated thyroglobulin level [sTg] with antibodies (IU/ml) at the time of RAI treatment were included. All had a normal serum creatinine level. To attain lower effective half-life good hydration and administration of soft laxative were ensured. Dose rate was measured (immediately, 24 h and 36 h) at 1 meter distance from anterior mid trunk and a dose rate <$50{\mu}Sv/h$ was considered as the releasing criterion. At 24 h 50 patients were released while the remaining 46 patients were released at 36 h. A post-ablative whole body scan (PA-WBIS) was performed 5-8 days after RAI ablation in all patients. Results: Patients released after 24 h were significantly younger, had smaller lesions with higher proportion of papillary cancer, lower sTg, lower sTg/TSH ratio and had received a lower dose of RAI as comapred to those who were discharged after 36 h. Serum TSH and gender were not found to have any significant correlation between two cohorts. ROC and multivariate analysis have shown age ${\leq}37years$, PTS ${\leq}3.8cm$, $RAI{\leq}150mCi$, $sTg{\leq}145ng/ml$ and $sTg/TSH{\leq}1.085$ as strong indepedent predictors for early release. Conclusions: We conclude that younger age (${\leq}37years$), smaller tumor size (${\leq}3.8cm$), lower RAI dose (${\leq}150mCi$), lower sTg (${\leq}145ng/ml$) and a lower sTg/TSH ratio (${\leq}1.085$) are significant independent predictors for release at 24 h after RAI treatment in DTC patients. Effective utilization of these factors could help the treating physicians to use limited number of internment facilities with higher throughput, lower cost and lower psychological stress to patients.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 1999년도 춘계공동학술대회:정보화시대의 지식경영
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• pp.426-426
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• 1999

;There are many sources of uncertainty in a typical production and inventory system. There is uncertainty as to how many items customers will demand during the next day, week, month, or year. There is uncertainty about delivery times of the product. Uncertainty exacts a toll from management in a variety of ways. A spurt in a demand or a delay in production may lead to stockouts, with the potential for lost revenue and customer dissatisfaction. Firms typically hold inventory to provide protection against uncertainty. A cushion of inventory on hand allows management to face unexpected demands or delays in delivery with a reduced chance of incurring a stockout. The proposed strategies are used for the design of a probabilistic inventory system. In the traditional approach to the design of an inventory system, the goal is to find the best setting of various inventory control policy parameters such as the re-order level, review period, order quantity, etc. which would minimize the total inventory cost. The goals of the analysis need to be defined, so that robustness becomes an important design criterion. Moreover, one has to conceptualize and identify appropriate noise variables. There are two main goals for the inventory policy design. One is to minimize the average inventory cost and the stockouts. The other is to the variability for the average inventory cost and the stockouts The total average inventory cost is the sum of three components: the ordering cost, the holding cost, and the shortage costs. The shortage costs include the cost of the lost sales, cost of loss of goodwill, cost of customer dissatisfaction, etc. The noise factors for this design problem are identified to be: the mean demand rate and the mean lead time. Both the demand and the lead time are assumed to be normal random variables. Thus robustness for this inventory system is interpreted as insensitivity of the average inventory cost and the stockout to uncontrollable fluctuations in the mean demand rate and mean lead time. To make this inventory system for robustness, the concept of utility theory will be used. Utility theory is an analytical method for making a decision concerning an action to take, given a set of multiple criteria upon which the decision is to be based. Utility theory is appropriate for design having different scale such as demand rate and lead time since utility theory represents different scale across decision making attributes with zero to one ranks, higher preference modeled with a higher rank. Using utility theory, three design strategies, such as distance strategy, response strategy, and priority-based strategy. for the robust inventory system will be developed.loped.

• 재무관리연구
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• 제26권1호
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• pp.165-188
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• 2009

본 연구는 개별 자산의 수익률 분포에 대한 가정 없이 평균-VaR 기준에서의 프론티어 포트폴리오를 구하고, 수익률 분포의 고차 적률에 대한 투자자의 선호가 반영된 최적 포트폴리오를 선택하는 방법을 제시하였다. 프론티어 포트폴리오를 구하기 위해 수익률 분포에 대한 가정이 필요하지 않은 그리드와 랭크 방법을 제시하였고 최적 포트폴리오를 선택하기 위해 수익률 분포의 4차 적률까지 고려된 효용함수를 사용하였다. 제시한 방법론을 실제 자료에 적용해 보기위해 모건 스탠리에서 제공하는 선진국 지수, 개발도상국 지수, KOSPI 지수의 주별 수익률 자료를 사용하였다. 평균-VaR 기준과 평균-분산 기준에서의 프론티어 포트폴리오를 구하고 각 기준에서의 최적 포트폴리오를 선택해 서로 비교하였다. 표준편차의 차이뿐만 아니라 효용함수의 수준과 주별 기대수익률로 표현되는 확실성 등가의 차이를 살펴봄으로써 두 기준 간의 경제적 의미 차이에 대해서도 살펴보았다. 또한 부트스트래핑을 이용한 역사적 시뮬레이션의 방법을 사용해 두 기준 간 발생한 차이가 통계적으로 유의한 지를 본 연구에서 적용한 자료에서는 평균-VaR 기준의 투자자가 평균-분산 기준의 투자자에 비해 더 큰 표준편차를 지닌 최적 포트폴리오를 선택하고 위험 회피도가 큰 투자자일수록 평균-VaR 기준에서의 효용이 크고 확실성 등가도 더 크게 나타나는 경향이 나타났다. 그러나 두 기준 간 발생한 차이가 통계적으로 유의하지 않게 나타나 표준편차의 차이와 경제적인 의미 차이가 크지 않다는 사실을 확인하였다.

• 한국강구조학회 논문집
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• 제20권6호
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• pp.773-781
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• 2008

건축물이 초고층화, 장스팬화가 되어갈수록 고강도, 신뢰성이 우수한 강재의 사용요구가 증대되고 있다. 그러나 강재가 고강도화가 되어갈수록 일반강재와는 다른 기계적 특성을 갖게 된다. 본 연구에서는 600MPa급 고강도 강재에 대한 건축구조용 강재로서의 적합성, 용접성 및 기계적 특성을 파악하기 위하여 소재특성 및 용접부 특성을 평가하였다. 화학시험결과, 대상강재는 낮은 탄소당량(${\mathcal{Ceq}}$) 및 용접갈라짐 감수성 조(${\mathcal{Pcm}}$)성을 가진 것으로 나타났으며, 인장시험결과로부터 모든 시험체의 항복강도는 설계기준강도를 만족하는 것과 인장강도가 600MPa이상인 것을 확인하였다. 충격시험결과, 모든 시험체는 KS 규격 값인 47J이상을 나타내었다. 또한 용접부 최고경도시험에서도 상온과 예열시의 경화정도가 큰 차이가 없는 것으로 나타났다. 그러나 용착금속 경우 강재의 성능에 미치지 못하여 고성능 고강도 강재용 용착금속의 개발 및 용접조건을 세밀히 파악할 필요가 있는 것으로 판단된다.

• 방사성폐기물학회지
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• 제2권1호
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• pp.1-11
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• 2004

한국원자력연구소에서는 고온의 용융염 매질 하에서 사용 후 핵연료를 환원시키는 차세대관리종합공정 연구를 수행 중에 있다. 추후 본 기술개발을 실증시험 하기 위해서는 방사선 차폐능이 확보된 핫셀이 필수적이며, 핫셀은 최대 1,385TBq의 방사능량에 대한 차폐 안전성을 가져야 한다. 최대 방사선원에 대한 핫셀의 차폐능을 확보하기 위하여, 본 연구에서는 실증시험 시 사용후핵연료부터 발생하는 중성자 및 감마선에 의한 선량률이 법적 허용선량치보다 낮게 유지되도록 핫셀의 차폐 설계에 대한 안전성을 평가하였다. QAD-CGGP 및 MCNP-4C 코드를 이용하여 핫셀 차폐체의 설계치에 대한 차폐 계산을 수행하였다. 작업구역에 대한 감마선 차폐계산 결과 QAD-CGGP 코드는 2.10${\times}$$10^{-3}$, 2.97${\times}$$10^{-3}$ mSv/h, MCNP-4C 코드는 1.60${\times}$$10^{-3}$, 2.99${\times}$$10^{-3}$ mSv/h 이었으며, 서비스 구역은 1.01${\times}$$10^{-2}$, 7.88${\times}$$10^{-2}$ mSv/h 로 평가되었다. 그리고 MCNP-4C코드를 이용하여 중성자에 의한 선량률을 계산한 결과, 중성자에 의한 선량률은 감마에 의한 선량률의 약 20% 이하치를 나타내었다. 따라서 선량률 대부분은 감마선에 의한 영향임을 알 수 있었다. 본 연구를 통하여 핫셀의 차폐 설계치가 작업구역의 선량 제한치 0.01 mSv/h 와 서비스 구역에서의 선량 제한치 0.15 mSv/h를 만족시키는 것을 확인할 수 있었다.

• 한국농공학회지
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• 제22권3호
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• pp.75-87
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• 1980

Most hydro]ogic phenomena are the complex and organic products of multiple causations like climatic and hydro-geological factors. A certain significant correlation on the run-off in river basin would be expected and foreseen in advance, and the effect of each these causual and associated factors (independant variables; present-month rainfall, previous-month run-off, evapotranspiration and relative humidity etc.) upon present-month run-off(dependent variable) may be determined by multiple regression analysis. Functions between independant and dependant variables should be treated repeatedly until satisfactory and optimal combination of independant variables can be obtained. Reliability of the estimated function should be tested according to the result of statistical criterion such as analysis of variance, coefficient of determination and significance-test of regression coefficients before first estimated multiple regression model in historical sequence is determined. But some error between observed and estimated run-off is still there. The error arises because the model used is an inadequate description of the system and because the data constituting the record represent only a sample from a population of monthly discharge observation, so that estimates of model parameter will be subject to sampling errors. Since this error which is a deviation from multiple regression plane cannot be explained by first estimated multiple regression equation, it can be considered as a random error governed by law of chance in nature. This unexplained variance by multiple regression equation can be solved by stochastic approach, that is, random error can be stochastically simulated by multiplying random normal variate to standard error of estimate. Finally hybrid model on estimation of monthly run-off in nonhistorical sequence can be determined by combining the determistic component of multiple regression equation and the stochastic component of random errors. Monthly run-off in Naju station in Yong-San river basin is estimated by multiple regression model and hybrid model. And some comparisons between observed and estimated run-off and between multiple regression model and already-existing estimation methods such as Gajiyama formula, tank model and Thomas-Fiering model are done. The results are as follows. (1) The optimal function to estimate monthly run-off in historical sequence is multiple linear regression equation in overall-month unit, that is; Qn=0.788Pn+0.130Qn-1-0.273En-0.1 About 85% of total variance of monthly runoff can be explained by multiple linear regression equation and its coefficient of determination (R2) is 0.843. This means we can estimate monthly runoff in historical sequence highly significantly with short data of observation by above mentioned equation. (2) The optimal function to estimate monthly runoff in nonhistorical sequence is hybrid model combined with multiple linear regression equation in overall-month unit and stochastic component, that is; Qn=0. 788Pn+0. l30Qn-1-0. 273En-0. 10+Sy.t The rest 15% of unexplained variance of monthly runoff can be explained by addition of stochastic process and a bit more reliable results of statistical characteristics of monthly runoff in non-historical sequence are derived. This estimated monthly runoff in non-historical sequence shows up the extraordinary value (maximum, minimum value) which is not appeared in the observed runoff as a random component. (3) "Frequency best fit coefficient" (R2f) of multiple linear regression equation is 0.847 which is the same value as Gaijyama's one. This implies that multiple linear regression equation and Gajiyama formula are theoretically rather reasonable functions.

• 터널과지하공간
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• 제30권4호
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• pp.404-416
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• 2020

2차원 응력조건에서 V형 암석노치의 파괴하중을 계산하는 해석적 절차를 slip-line 소성해석법 기반으로 개발하였다. 노치 주변의 암석이 소성상태에 있을 때 slip-line 중 하나인 α선이 암석 노치 면과 노치 외부 수평면을 연결한다는 사실과 α선을 따라서 변하지 않는 불변량이 존재한다는 이론적 사실이 해석적 절차 개발과정에서 핵심 아이디어로 활용되었다. 암석 노치 외부 수평면의 응력 경계조건을 알고 있으므로 불변량 방정식을 풀면 암석 노치 면에 작용하는 수직응력과 전단응력을 계산하는 것이 가능해진다. 노치 면에 작용하는 응력성분 값을 이용하여 쐐기에 의해 노치에 가해지는 파괴하중을 계산하였다. 개발된 해석적 절차를 적용하여 암석 노치파괴 해석을 수행하였다. 암석 노치의 파괴하중은 노치의 각도 및 노치 면의 마찰이 증가함에 따라 지수함수적 비선형성을 가지고 증가하는 특성이 있음을 해석결과는 보여주었다. 이 연구에서 개발한 해석적 절차는 쐐기형 노치 형성을 통한 암석균열 개시조건 연구, 암반 기초 지지력 계산, 암반사면 및 원형터널의 안전성 해석 등에 응용될 수 있을 것으로 기대된다.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2009년도 특별 Symposium
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• pp.49-57
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• 2009

The cloning of canids was succeeded in 2005, several years after the birth of Dolly the sheep and also after the cloning of numerous other laboratory and farm animal species. The delay of successful somatic cell nuclear transfer (SCNT)was due to the unique reproductive characteristics of the female dogin comparison to other domestic mammals, such as ovulation of immature canine oocyte and a requirement of 25 days for the completion of meiosis within the oviduct (Holst & Phemister, 1971). When the technology for the recovery of in vivo matured oocyte was established, the application of cloning also became possible and cloned dog offspring were obtained. This report summarizes the progress of technical procedures that are required for cloning canids and the application of this technique. The first cloned dog, Snuppy, was achieved using an in vivo-matured oocyte which was enucleated and transferred with an adult skin cell of male Afghan hound. After establishment of a criterion of well-matured oocyte for the improvement of SCNT efficiency, we obtained three cloned female Afghan hound and a toy poodle cloned from 14 year-old aged Poodle using SCNT through this factor. To date, cloned dogs appeared to be normal and those that have reached puberty have been confirmed to be fertile. Through application of canine SCNT technique, first, we demonstrated that SNCT is useful for conserving the breed of endangered animal from extinction through cloning of endangered gray wolves using inter-species SCNT and keeping the pure pedigree through the cloning of Sapsaree, a Korean natural monument. Secondly, we showed possibility of human disease model cloned dog and transgenic cloned dog production through cloning of red fluorescent protein expressing dog. Finally, SCNT can be used for the propagation of valuable genotypes for making elite seed stock and pet dog. In summary, dog cloning is a reproducible technique that offers the opportunity to preserve valuable genetics and a potential step towards the production of gene targeted transgenic cloned dogs for the study of human diseases.

• 대한소아치과학회지
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• 제40권1호
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• pp.21-27
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• 2013

현재까지의 많은 연구들을 통해 치아의 발육상태와 골격성 부정교합과의 연관성이 보고되어 왔다. 본 연구는 방사선학적 방법을 통하여 정상교합군과 하악 과성장형 골격성 3급 부정교합군의 상하악 치령 및 제2대구치 맹출률을 비교, 분석하여, 파노라마 방사선 사진으로 평가 가능한 상하악 치아성숙도의 차이가 하악 과성장형 골격성 3급 부정교합의 감별진단 요소로 의의가 있는지 알아볼 목적으로 시행되었다. 부산대학교 소아치과에 내원한 Hellman 치령 IIIA의 환자를 대상으로 정상교합군과 하악 과성장형 골격성 3급 부정교합군 각 50명을 선택한 후, 이들의 파노라마 방사선 사진을 이용하여 Demirjian법으로 각 군의 상하악 치령 및 제2대구치 맹출률을 구하고 그 차이를 비교, 분석하였다. 그 결과 정상교합군과 하악 과성장형 골격성 3급 부정교합군의 상하 치령의 차이는 각각 0.66세와 1.20세로 하악 과성장형 골격성 3급 부정교합군에서 유의하게 더 큰 차이를 보였으며(p < 0.05), 상하 제2대구치 맹출률은 두 그룹 간 유의한 차이를 보이지 않았다(p > 0.05).