방사선물질을 수송하기 위한 용기는 가상 사고조건에서도 안전해야만 한다. 운반용기 설계요구조건은 실험 및 유한요소 해석을 통해 구조적 건전성을 확보하여야 한다. 최근에는 실험보다 유한요소해석을 이용한 방법이 상대적으로 비용이 적기 때문에 주로 사용된다. 그러나 기계적인 반응이 복잡하기 때문에 프로그램을 적용하는 사용자의 방법에 의해 결과가 결정되고 해석하는 동안 여러가지 문제를 발생시킬 수 있다. 본 논문에서, 유한요소해석은 LS-DYNA3D와 ABAQUS/Explicit을 이용하여 운반용기의 9m 자유낙하충격실험에 대한 해석기술과 여러가지 손상을 갖는 경우를 발견하기 위해 연구하였다. 운반용기의 각각의 경우를 비교하고 사용후 핵연료 운반용기의 낙하 실험에 대해서 신뢰할 수 있는 비교적 간단한 해석 기술을 제안하였다.

The purpose of this study is to propose guidelines for introducing the Just-In-Time (JIT) production system to enhance the competitiveness of Korean manufacturing companies. This study employed an extensive survey on the use of the JIT production systems

The main goal of this work is to study the effects of temperature and volume fraction of fiber on the Charpy impact test with GF/PP composites. The critical fracture energy and failure mechanisms of GF/PP composites are investigated in the temperature range of 60℃ to -50℃ by impact test. The critical fracture energy increased as the fiber volume fraction ratio increased. The critical fracture energy shows a maximum at ambient temperature and it tends to decreases as temperature goes up or goes down. Major failure mechanisms can be classified such as fiber matrix debonding, fiber pull-out and/or delamination and matrix deformation.

This paper describes to evaluate the performance of ventilation as a change of CO2 concentration with ventilation rate under 35 occupants in a school classroom. Variations of the CO2 concentration as a function of time are measured at center point of classroom with air ventilation rates by the CO2 gas monitor. For 800 m3/h of ventilation rate in the classroom, the average CO2 concentration is 913 ppm. The ventilation rate is sufficient to meet acceptable indoor air quality (≤ 1,000 ppm of CO2, KS school standard) in the classroom of 35 students.

Since the teaching of English was introduced into the primary school as a required subject in 1997, no achievement test has been administered for the purpose of comparing English achievement of primary school students who are receiving private instruction with that of those who are not. The purpose of this study was to investigate what impact private instruction had on English achievement of third- and fourth-year students in the primary school. For this purpose, an English achievement test was developed based on the 7th national curriculum and two questionnaires were administered: one questionnaire among 743 third- and fourth-year primary school students and the other among 22 primary school teachers. The results showed that students who were receiving private instruction outperformed those who were not on the English achievement test and that teachers had difficulty in handling English class due to the discrepancy of overall English proficiency between tutored students and non-tutored students. The findings suggest that teacher training needs to be intensified to ensure quality English language teaching in the primary school.

The following paragraph is extracted from an email message written by a German medical doctor working in Papua New Guinea (PNG) since 1999. I was impressed the most by a 15-year-old boy who arrived out of the bush in a health center complaining about lower-right abdominal pain. Due to the possibility of an appendix infection, he had to be transferred to the hospital. But the sea was rough, and he had to wait for two days at the health center. Then a so-called banana boat, a boat with an outboard motor, brought him in a 6-hour trip to Vunapope [a town in PNG]. Even for healthy people such a trip with all the up and down is not a pleasure. As it turned out, the appendix had broken through and quite some pus had collected in his abdomen. In spite of the pain medication, the trip on the boat must have been hell for the boy, but he endured it courageously. The doctor regularly reports about her life and adventures in PNG to her friends and sponsors viaemail. The stories in her e-mail messages are often fascinating and sometimes heartbreaking. Life m PNG is far beyond what some of us can imagine. This article reports on information technology (IT) in PNG, particularly as it affects education and cultural development. The findings are based on data collected from the medical doctor and a school principal, both currently working in PNG. The purpose of the article is not to present sophisticated research results but to offer a glimpse of IT culture in PNG. It starts with a brief overview of IT in developing countries and then focuses on PNG.

The Charpy and Izod impact tests are the most prevalent techniques used to characterize the effects of high impulse loads on polymeric materials. An analysis method for rubber toughened PVC is suggested to evaluated critical dynamic strain energy release rates(Gc) from the Charpy impact tester was used to extract ancillary information concerning fracture parameters in additional to total fracture energies and maximum critical loads. The dynamic stress intensity factor KID was computed for varying amounts of rubber contents from the obtain maximum critical loads and also toughening effects were investigated as well. The fracture surfaces produced under low velocity impact for PVC/MBS composites were investigated by SEM. The results show that MBS rubber is very effective reinforcement material for toughening PVC.

The vertical impact crusher is the machine which could produce artifical sand similar to natural aggregates in the site of guarry and pits. FEM was used to analyse the stress and strength of the machine at high rotational speed. The test specimen was made from the same material as the shaft and tension tests were conducted. The Shaft under extreme conditions was analysed to determine maximum stress level and its location from the results. The maximum level of stress and its location could be predicted.

We developed the logical methods to analyze economic impacts of standardization and applied these analytical ways into performing this studies in micro and macro aspects. This study is performed through analysing foreign studies and results from surveys. The advanced methods performing standardization as a form of "korean standards" are suggested here. which are based on results of this study. The major consequences of this study are followings. The economic micro impact is that each company gets 604.5 millions won a year through performing KS A, F(discount rate 4.5%) and 1.46 trillions won is the macro economic impact through performing total KS A, F, which comes to 0.245% of GDP.

랜덤동요된 조화가진력을 받는 임팩트시스템의 비선형거동을 개발된 반해석적절차에 의해 확률영역에서 분석하였다. 반해석적절차는 path-integral solution을 이용하여 임팩트시스템의 추계론적 미분방정식으로부터 구함으로 얻어진다. 결합확률밀도함수의 전개를 구하고 시스템의 비선형거동 특성인 혼돈거동에 대하여 분석하고 노이즈의 영향을 시간영역과 확률영역에서 알아보았다. 결과로부터 반해석적절차는 결합확률밀도함수를 통하여 임팩트시스템의 거동에 대한 정보를 제공하는 것을 알 수 있었다. 노이즈의 영향은 혼돈거동의 특성을 약화시키며 궁극적으로 사라지게 함을 알 수 있었으며 또한 혼돈거동의 특성이 상대적으로 높은 노이즈아래에서도 남아있는 것을 밝혔다. 결합확률밀도함수는 응답앙상블이 약정상과정임을 확인시켜 주었다.