• 대한기계학회논문집B
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• 제34권6호
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• pp.615-622
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• 2010

본 연구에서는 중형 직분식 선박용 엔진의 성능 및 NOx 배출물 예측을 위한 0-D multi-zone 분무 연소 모델이 개발되었다. 모델은 상용 1-D 사이클 해석 프로그램 (Boost)와 연동할 수 있도록 개발되었으며, 흡배기 시스템을 포함한 엔진 전체에 대한 동시 해석이 가능하였다. 연소 모델은 Fortran90 으로 개발되었으며, AVL 에서 제공된 'user defined high pressure cycle (UDHPC) interface'를 통해 Boost 와 연동되었다. 두 가지의 인젝터(8 홀, 10 홀)에 대해 두 가지 부하에서 해석을 수행하였으며, 해석 결과는 실제 엔진의 성능 실험 결과를 잘 추종하였다.

• Journal of Preventive Medicine and Public Health
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• 제37권1호
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• pp.26-36
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• 2004

Objective : To examine the association between hospital procedure volume and treatment outcomes following allogeneic bone marrow transplantation (allo-BMT). Methods : Out of 1,050 patients who received allo-BMTs between 1998 and 2000 in 21 Korean hospitals, 752 with first allo-BMT and complete data were included in this study. Study subjects were divided into the following three groups according to cumulative hospital experience of all-BMTs during the study period: low (<30 cases), medium (30-49) and high ($\geq$50 cases) volume. Patient outcome was defined as early survival at day 100 and one-year survival. Multiple logistic regression analyses were performed to examine the association between hospital experience and survival at day 100 and one year. Results : When the low volume group was defined as the reference group, the adjusted relative risks (RR) of survival at day 100 for the high volume group were 2.46(95% CI, 1.13-5.36) for all patients, 2.61(1.04-6.57) for those with leukemia, and 2.20(0.47-10.32) for those with aplastic anemia. For one-year survival, adjusted RR for the high volume group were 2.52(1.40-4.51) for all patients, 1.99 (1.01-3.93) for leukemia, and 6.50(1.57-26.80) for aplastic anemia. None of the RR for the medium volume group was statistically significant. Patient factors showing significant relationship with survival were donor-recipient relation, human leukocyte antigen matching status, time from diagnosis to transplant, and disease stage. Conclusions : The study results suggest that the cumulative experience of hospitals in providing allo-BMT is positively associated with patient survival.

• 산업경영시스템학회지
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• 제44권2호
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• pp.43-57
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• 2021

Smart factories can be defined as intelligent factories that produce products through IoT-based data. In order to build and operate a smart factory, various new technologies such as CPS, IoT, Big Data, and AI are to be introduced and utilized, while the implementation of a MES system that accurately and quickly collects equipment data and production performance is as important as those new technologies. First of all, it is very essential to build a smart factory appropriate to the current status of the company. In this study, what are the essential prerequisite factors for successfully implementing a smart factory was investigated. A case study has been carried out to illustrate the effect of implementing ERP and MES, and to examine the extensibilities into a smart factory. ERP and MES as an integrated manufacturing information system do not imply a smart factory, however, it has been confirmed that ERP and MES are necessary conditions among many factors for developing into a smart factory. Therefore, the stepwise implementation of intelligent MES through the expansion of MES function was suggested. An intelligent MES that is capable of making various decisions has been investigated as a prototyping system by applying data mining techniques and big data analysis. In the end, in order for small and medium enterprises to implement a low-cost, high-efficiency smart factory, the level and goal of the smart factory must be clearly defined, and the transition to ERP and MES-based intelligent factories could be a potential alternative.

• 대한화학회지
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• 제44권3호
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• pp.207-211
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• 2000

Tween80 미셀용액에서 착화제로서 APDC틀 이용하여 Ni(II)를 정량하는 방법에 대해 연구하였다. Ni(PDC)$_2$ 착물의 홉수 스펙트럼 chloroform에서 보다는 Tween80에서 더 좋은 모양과 더 좋은 감도를 보여 주었다. Ni(PDC)$_2$ 착물은 pH 7.0에서 그리고 100분 정도까지 매우 안정하였으며, APDC를 Ni(II)의 몰수의 10배 이상 넣어 주면 정량적으로 착물이 형성되었다. Tween80의 농도는 0,1%가 적절하였고,0.1% Tween80 용액에서 Ni(PDC)$_2$ 착물의 검정곡선은 좋은 직선성(R2=0.9955)을 보여주었다. 이 분석법의 검출한계와 정량한계는 각각 0.09 ${\mu}g$/mL와 0.28${\mu}g$/mL이었으며, 강물시료에 적용한 회수율은 100% 보다 조금 크게 나타났다. 비록 여러 금속이온들이 방해를 하지만, 실제시료에 들어있는 Ni(II)을 정량하는데 이용할 수 있을 것이다.

• 한국가축번식학회지
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• 제21권2호
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• pp.95-102
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• 1997

The studies on the carried out to investigate the effective concentration of cryoprotectant agents and sucrose by one-step straw method of bovine embryos. The follicular oocytes were cultured in TCM-199 medium containing 10 IU/ml PMSG(Sigma, USA), 10 IU/ml hCG(Sigma, USA), 1$\mu\textrm{g}$/ml $\beta$-estradiol(Sigma, USA) and 10% FCS for 24~48 hrs in incubator with 5% CO2 in air at 38.5$^{\circ}C$ and then matured oocytes were again cultured for 12~18 hrs with motile capacitated sperm by preincubation of heparin. The bovine embryos following dehydration by cryoprotective agents and various concentrations of sucrose were directly plunged into liquid nitrogen and thawed in 3$0^{\circ}C$ water. Survival and in vitro developmental rate was defined as devellpmental rate on in vitro culture or FDA-test. The results are smmarized as followes : 1. The high in vitro developmental rates of bovine frozen embryos after rapidly thawed in freezing medium was attained 2.0M glycerol, 2.0M DMSO, 1M or 2.0M propanediol. 2. The high in vitro developmental rates of bovine frozen embryos after rapidly thawed in freezing medium was obtained single cryoprotectant(6.7~17.4%) than mixed cryoprotectants(6.7~16.7%). 3. In vitro developmental rate of bovine embryos after rapid frozen-thawing in the freezing medium added 0.25M and 0.50M sucrose were higher cleavage rate than those of sucrose concentration of 0.75M and 1.00M. 4. The freezing methods on in vitro developemental rates of bovine embryos was attained slow freezing method(9.70~15.6%) higher than rapid freezing method(9.4~13.3%).

• Clinical and Experimental Reproductive Medicine
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• 제42권4호
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• pp.175-180
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• 2015

Objective: Embryo loading (EL) is a major step in embryo transfer (ET) and affect on the success of in vitro fertilization (IVF). This study aimed to compare the effect of two different EL techniques on the rates of pregnancy and delivery in IVF/ET cycles. Methods: 207 fresh ET and 194 Frozen-thawed ET (FET) cycles were included in this retrospective study. Two groups (A and B) were defined based on the EL technique used. In group A, the entire catheter was flushed with Ham's F-10 medium. The embryos were then drawn into the catheter using one air bracket. In group B, $70{\mu}L$ of air was aspirated into the syringe and the catheter was flushed using Ham's F10 medium. The medium, air, embryos, air, and finally another layer of medium were then sequentially drawn into the catheter. The main outcome measures were the pregnancy and delivery rates. Results: The groups did not differ with respect to the etiology of infertility, the source of spermatozoa, the quality of the embryos, the type of EL catheter, and the ease of transfer. The pregnancy rate was similar between two groups. In fresh ET cycles, a higher delivery rate was observed in group B than it group A (78.1% vs. 60%, p=0.1). In FET cycles, the rate of delivery was significantly higher in group B than in group A to a nonsignificant extent (88.9% vs. 58.8%, p=0.06). Conclusion: EL techniques did not have a significant impact on the delivery rate in either fresh or FET cycles.

• 한국수정란이식학회지
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• 제15권2호
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• pp.129-136
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• 2000

This study was carried out to investigate the effect of biological factors on the in vitro production(IVP) of bovine oocytes for development of simple culture methods and medium. Oocytes from the slaughterhouse ovaries were matured and fertilized using general protocol and this study was examined if there were necessary to co-culture, media change, media type and embryo density. This results were as follows: 1. The development rate according to co-culture with cumulus cells and non co-culture as drop culture was not significantly different in cleavage (68.9 vs 71.7%), 8-cell stage (41.2 vs 44.1%) and blastocyst stage (12.2 vs 13.8%), respectively (p<0.05) 2. The blastocyst development rates in YS and CRIaa were higher than that in TCM199 (12.4, 10.4$ vs 3.7%), but the cleavage (69.0, 77.8 and 61.0%) and 8-cell stage (31.7, 37.0 and 35.7%) development accoring to YS, TCM199 and CRIaa ws not significantly different, respectively (p<0.05). 3. There was no significantly different in cleavage (62.6, 59.5 and 61.2%), 8-cell(34.7, 37.9 and 34.0%) and blastocyst (9.5, 11.6 and 12.8%) development among medium change time as control, Group I and Group II, respectively (p<0.05). 4. Blastocyst formation of 8-cell stage according to embryo density was not significantly different in 1, 10 and 25 embryos (27.3, 22.5 and 34.0%), respectively (p<0.05). These results indicated that simple culture system could reduce bovine IVP embryos as drop culture as non co-culture system, high density embryo (25 embryos/50 $\mu$1 drop). YS defined medium and no medium change for whole culture period, although other biological factors need to examine in order to produce efficient IVP bovine embryos.

• 한국전산구조공학회논문집
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• 제26권6호
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• pp.431-438
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• 2013

건설 산업의 전반적인 생산성 향상을 위하여 시설물의 전 생애주기에 걸쳐 정보의 시스템화가 요구되고 있다. 정보를 시스템화하는 방법의 하나로 3차원 정보모델을 기반으로 정보 관리하는 기술인 BIM(Building Information Modeling)이 활발하게 연구되고 있다. 하지만 BIM 연구의 초점은 대형 사업장에 맞추어져 있으며 중소규모 사업장을 위한 BIM 연구는 미비한 실정이다. 중소규모 사업장의 경우 대형 사업장보다 정보 손실이 더욱 심각하지만, 투자 자원의 부족으로 인해 BIM을 도입하기에는 힘든 실정이다. 따라서 이 논문에는 과도한 투자 없이 BIM의 효과를 얻을 수 있는 중소규모 사업장 대상 맞춤형 BIM 시스템 개발을 위한 연구를 수행하였다. 이를 Pseudo BIM(이하, 의사BIM)이라 정의하였다. 그리고 의사 BIM의 개념과 구축방법에 따라 PLIB Part 42, 건설정보분류체계 등을 활용하여 의사 BIM의 엔진 구조를 담당하는 데이터 사전 구축 방법을 제시하고 Pilot test를 실시하여 의사 BIM의 유효성을 검증하였다.

• 한국균학회지
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• 제15권4호
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• pp.238-246
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• 1987

1. 검정곰팡이(Aspergillus niger)를 실험균주로 하여 동조적으로 액침배양한 결과 포자의 발아로 부터 균사의 생장, 생식기관의 성숙 및 무성포자의 형성까지를 재현시켰다. 2. 포자형성용 배지(D배지)에 cAMP를 첨가한 실험구에 있어서는 포자형성이 촉진되었고, 그 최적 농도는 $10^{-4}M$이었다. 3. 포자형성용 배지(D배지)에 첨가한 테오필린은 포자형성을 촉진하였고, 그 최적농도는 10mg/ml이었다. 4. 포자형성용 배지(D배지)에 첨가한 카페인은 포자형성을 촉진하였고, 그 최적농도는 300mg/ml이었다. 5. 포자형성용 배지(D배지)에 cAMP와 테오필린을 함께 첨가한 실험구에서는 cAMP 단독 첨가 실험구보다 포자형성 촉진효과가 더욱 강화되었다. 6. 포자형성용 배지(D배지)에 cAMP와 카페인을 함께 첨가한 실험구에서는 cAMP 단독 첨가 실험구보다 포자형성 촉진효과가 더욱 강화되었다. 7. 포자형성용 배지(D배지)에 AMP나 ATP를 첨가한 실험구에서는 포자형성 촉진효과가 거의 없었다. 8. 아세트산염 배지에 cAMP, 테오필린, 카페인을 각각 첨가한 실험구에서는 포자형성에 대해 촉진효과를 나타내었다.

• 천문학회지
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• 제28권1호
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• pp.15-30
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• 1995

A velocity inhomogeneity, which is defined as a regional preponderence of either radial or tangential orbits, is searched with a new technique for the Coma cluster of galaxies. It is found within $\~2h^{-1}$ Mpc from the cluster center that the Coma shows conspicuous inhomogeneities in velocity and that the inhomogeneities are real at a $99\%$ level of confidence. Even in the central region (7' - 30' from the center), zones that are dominated by radial and tangential orbits are distinguishable. Defining the cluster's 'equator' as the direction defined by the Coma-A1367 supercluster, tangential orbits dominate the 'polar' zones in the central region. Galaxies that are located in 30'-100' also inhomogeneous in velocity in that the 'polar' zones are mostly radial while the rest is nearly homogeneous. These results indicate that the Coma galaxies are exceedingly more radial in orbit, implying that merging or infalls are either still going on or an earlier virialization is likely to have occurred preferentially near the 'equator'. Incorporating the velocity inhomogeneity into mass estimators, the most appropriate mass is turned out to be $0.4\times10^{15}h^{-1}M_\bigodot(R\;\leq\;0.6h^{-1} Mpc),\;and\;1.0\times10^{15}h^{-1} M_\bigodot(R\;\leq\;2.1h^{-1}Mpc)$. The corresponding mass to blue light ratio on the average is $\~$300h. These estimates are consistent with Merritt (1987) and Hughes (1989) and the MILE is seemed to favour the mass-follows-light models than the uniform spread of dark matter throughout the cluster.