인간포배기 배아의 효과적인 유리화 동결법의 개발을 위한 연구

이상민,이주희,이상원,이승민,윤산현,임진호,박흠대,이성구,Lee, Sang-Min,Lee, Ju-Hee,Lee, Sang-Won,Lee, Seoung-Min,Yoon, San-Hyun,Lim, Jin-Ho,Park, Huem-Dai,Lee, Seong-Goo 대한생식의학회 2003 Clinical and Experimental Reproductive Medicine Vol.30 No.3

Objective: The purpose of this study was to evaluate the survival rate of vitrified blastocyst according to the freezing vessels, equilibration time in cryoprotectant and artificial dehydration method. Methods: Human blastocysts were vitrified after loading onto the plastic straw, open-pulled straw (OPS), electron microscopy grid (EM grid) for 1.5 min or 3 min. They also were directly plunged into LN2 within 30sec. For artificial shrinkage of blastocysts, 36 gauge fine needle was pushed at the cellular junction of the trophectoderm into the blstocoele cavity until it shrank without damage of inner cell mass. Results: The survival rate of vitrified blastocysts on plastic straw, OPS, EM grid as freezing vessels were 26.7, 13.0 and 60.5%, respectively. The survival rate of EM grid was significantly higher than that of plastic straw and OPS (p<0.05). For 1.5 min equilibrium, the survival rates of early blastocyst (EB), middle blastocyst (MB) and late blastocyst (LB) were 64.4, 81.0, and 20.0% respectively. For 3 min equilibrium, the survival rates of EB, MB, and LB were 69.9, 50.0 and 57.5% respectively. The survival rates of EB and MB were significantly higher than that of LB in 1.5 min equilibrium group (p<0.05), however, the significance was not observed in 3 min equilibrium groups. In cytoplasmic shrinkage before vitrification, the survival rates of EB, MB and LB were 92.9, 100 and 75.9% respectively. The survival rate of MB was significantly higher than that of LB (p<0.05). The survival rates of vitrified blastocysts by artificial dehydration and slow-frozen blastocysts were not significantly different as 88.9 and 66.7%, respectively. Conclusion: This study showed that the vitrification of human blastocysts using EM grid and artificial dehydration is an effective method. Therefore, these methods would be an useful techniques for blastocyst cryopreservation.

실험 평가를 통한 탐구과정 기능의 성취도와 인지 수준과의 관계 분석

민혜영,백성혜,강대훈 한국교원대학교 과학교육연구소 1999 청람과학교육연구논총 Vol.9 No.1

본 연구의 목적은 실험 평가를 이용하여 탐구과정 기능을 측정하고, 인지 수준과 탐구과정 기능의 성취도와의 관계를 알아보는 것이다. 연구 대상은 인지 수준과 지역을 유층으로 하여 중학교 2학년 162명을 표집하였다. 실험 평가는 SISS에서 사용한 실험 과정기능검사 문항을 수정·보완한 산·염기, 밀도, 염화코발트의 성질에 관한 3가지 과제를 이용하여 순환실험 형식으로 수행하였다. 탐구과정 기능은 D(계획), P(수행), R(추론) 등의 하위 기능을 포함한다. 실험 평가의 채점은 학생용 보고서를 이용하였으며, 5면의 평가자가 채점한 결과의 평균값으로 분석을 하였다. 연구의 결과 인지 수준이 발달함에 따라 탐구과정 기능의 전체 점수와 하위 기능인 D(계획), P(수행), R(추론)의 성취도와 모두 통계적으로 유의미하게 높아지는 것으로 나타났다. 그리고 인지 수준을 통제하고 탐구과정 기능의 성취도를 비교한 결과 지역간에 탐구과정 기능의 성취도 차이와 남녀간에 탐구과정 기능의성취도 차이는 나타나지 않았다. 이러한 결과를 통해, 실험 평가를 통한 탐구과정 기능의 성취도는 인지 수준에 크게 영향을 받으므로 탐구과정 기능을 향상시키기 위해서는 학습자의 인지 수준을 고려하는 것이 매우 중요한 일임을 알 수 있다. The purpose of this study is to investigate the relationship between cognitive levels and achievement of science process skills. A science laboratory process skills test based on optional instrument of the SISS was administered to a sample of 162 students in the 8th grade. Practical assessment tasks consisted of the contents about acidㆍbase, density, and a property of cobalt chloride. The format of this practical test was the station type that students had to conduct a short activity. Science process skills included three sub-skills which were categorized as designing, performing, and reasoning. As cognitive levels develop from concrete operational stage to transition stage and formal operational stage, total scores of science process skills and mean scores of sub-skills were significantly increased. Regardless of cognitive levels, all students were more successful on performing than designing or reasoning. In case of being controlled cognitive levels, gender differences and area differences were not detected in achievement of science process skills. According to these results, there was a strong relationship between cognitive levels and achievement of science process skills by practical assessment. This study implies that considering student's cognitive levels is very important for improving science process skills.

AE센서를 이용한 레이저 용융 절단 모니터링

민헌식,이성환,안선응 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.3

As laser cutting process is widely used in industry, an automated on-line process control system has become very important. In this paper, development of a laser cutting monitoring system, which is regarded as the fundamental step toward automation of the process, is presented. Acoustic emission and an artificial neural network were used for the monitoring system. With given process parameters including laser power and scanning speed, the system can predict the suitability of laser beam for the cutting of a stainless steel (STS304) plate.

후복막강에 발생한 활막육종

채승완,심정원,안혜경,이민철,박영의 대한병리학회 1995 Journal of Pathology and Translational Medicine Vol.29 No.4

해안 잠재 수변공간 개발 대상지 선정에 관한 연구 : 기장군을 중심으로

민병형,김가현,유상호,민상철,이승휘 東亞大學校 海洋資源硏究所 2002 硏究論文集 Vol.14 No.1

This study is determin digging and development preferential ranking which is the potential area of seafront in Busan Kijanggun according to rise citizen of literary life and increase desire of culture life. Obtained results of this study are summarized as follows. 1. Decide to development preferential program that eight area selected from the potential area of seafront to position in Busan Kijjanggun. 2. Appraisal standard I decided to development preferential program which is Yunhwa gigu, Yonggung temple, Juksung estuary, Sirangdae, Munjung· Mundong harbor, Seoam harbor, Hoyamlee and Sinpyung harbor. 3. Appraisal standardII decided to development preferential program which Yunhwa gigu, Yonggung temple, Juksung estuary, Hoyamlee and Sirangdae, Seoam harbor, Sinpyung harbor and Munjung ·Mundong harbor get the same grade. 4. As a result of comparative appraisal standard I, II is that first~third program is equal but it was changed from fourth program. 5. When potential area in seafront appraised by Lee unit, appraisal standard I is superior than appraisal standardII.

海岸構造物 設置에 따른 全沿岸漂砂量의 推定精度와 One-line theory의 適用性

閔丙亨,金嘉也,李承煇,李英載 東亞大學校 海洋資源硏究所 1992 硏究論文集 Vol.5 No.2

A numerical model for practical use based ont he 'One-line gheory' is presented to Simulate shoreline change due to consruction of coastal sturctures. The model contains the part to calculate wave deformation for estimaters of wave energy flux at the breaking point . The lgorithm for wasve deformation is bsed on the wave-ray method and takes the following effects into account,i.e.wave refraction, shoaling reflection and diffraction.n

레이저 용융 절단 해석 프로그램 개발

민헌식,이성환 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.3

Though the laser cutting process is increasingly used in industry, a process automation and systematic database is still yet to be developed. In this study, as the fundamental step toward the construction of a reliable process expert system, a laser cutting quality monitoring/analysis system is developed based on simulation and experimental results. The relations between laser process parameters and laser cutting surface quality parameters such as kerf geometry, striation, surface roughness and dross formation are characterized and analyzed. A graphical user interface is used to visualize the results.

河床變動 豫測에 관한 硏究 : 密陽江이 合流하는 洛東江 本流地域을 中心으로

閔丙亨,李承輝,閔一圭,兪甲鎔,吳尙龍 동아대학교 건설기술연구소 1996 硏究報告 Vol.20 No.1

In this study, when we collect river bed sediment at the point where mainstream of Nak Dong river join branch of Mil Yang river, the change of river bed around downstream area was estimated and based on experimental data using three dimensional unsteady flow model about the water level to quantity of water and velocity and river bed change through numerical imitation experiment and hydraulic model experiment.

부정류 흐름을 이용한 부유물질 확산모형에 관한 연구

민병형,이승휘,민일규,유갑용,임대영 東亞大學校 海洋資源硏究所 1996 硏究論文集 Vol.9 No.1

To investigation the diffusion of suspended material we use a 3-D unsteady numerical model based on the Euler method. We applied the model to mainstream of Nak Dong River confluence of Miryang river place at KyungNam kimhae-Si Saenglim-Myon Masa-Ri. We pridicted the concentration of suspended material due to dredging at a near by water-supply intake.

금형면 자동 다듬질 전문가 시스템 개발에 관한 연구-Ⅱ : 통합 연마 파라미터를 사용한 최적 가공 구현 및 전문가 시스템 구축

민헌식,이성환,안유민,조남규,한창수 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.1

To reduce the cost and increase reliability of die and mold products, automation of the finishing (polishing) process is essential. A major element of automation is a reliable database and a knowledge base for polishing status. This paper presents a polishing expert system which can determine optimal polishing sequences and conditions by using an empirical formula and an experimental database. The simplex method was used for the cure fittings of the experimental results. Also a graphical user interface, which visualizes the optimized results, was developed.