The tendency to use a probabilistic design method rather than a deterministic design method for the design of nuclear power plants (NPPs) will increase because their safety should be considered and strictly controlled in relation to various causes of damage. The distance between a seismically isolated NPP structure and a moat wall is called the clearance to stop. The clearance to stop is obtained from the 90th percentile displacement response of a seismically isolated NPP subject to a beyond design basis earthquake (BDBE) in the probabilistic design method. The purpose of this study is to analyze the effects of heating and buckling effects on the 90th percentile displacement response of a lead-rubber bearing (LRB) subject to a BDBE. The analysis results show that considering the heating and buckling effects to estimate the clearance to stop is conservative in the evaluation of the 90th percentile displacement response. If these two effects are not taken into account in the calculation of the clearance to stop, the underestimation of the clearance to stop causes unexpected damage because of an increase in the collision probability between the moat wall and the seismically isolated NPP.

The Gyeong-Ju earthquake in the magnitude of 5.8 on the Richter scaleoccurred in September 12, 2016. Because there are many nuclear power plants (NPP) near the epicenter of the Gyeong-Ju earthquake, the seismic stability of nuclear power plants is becoming a social problem. In order to evaluate the safety of seismically isolated NPP, the seismic response of a NPP subjected to the Gyeong-Ju earthquake was compared with those of 30 sets of artificial earthquakes corresponding to the nuclear standard design spectrum (NSDS). A 2-node model and a simple beam-stick model were used for the seismic analysis of seismically isolated NPP structures. Using 2-node model, the effect of internal temperature rise, decrease of shear stiffness, increase of lateral displacement and decrease of vertical stiffness according to nonlinear behavior of lead-rubber bearing (LRB) were evaluated. The displacement response, the acceleration response, and the shear force response of the seismically isolated nuclear containment structure were evaluated using the simple beam-stick model. It can be observed that the seismic responses of the isolated nuclear structure subjected to Gyeong-Ju earthquake is significantly less than those to the artificial earthquakes corresponding to NSDS.

A survey of food preservatives, sulfur dioxide and microbial contamination levels was conducted on 73 seasoned dried fishes(41 squids, 17 filleted fish, 6 Alaska pollack, 9 others) collected from domestic markets and internet. Among preservatives, only sorbic acid was detected in 25 samples including 23 seasoned dried squids, 1 seasoned filleted fish and 1 seasoned dried Alaska pollack with a range 0.01~0.92 g/kg. Sulfur dioxide was detected from one sample(seasoned dried squid) and its content was 10.5 mg/kg. All samples were contaminated by total aerobic bacteria, and the degree was 3.00~6.45 log10CFU/g(average level was 5.09 log10CFU/g). Escherichia coli, Salmonella spp. and Staphylococcus aureus were not detected in all samples. On the basis of the results above, most of the seasoned dried fishes were appropriate for Korea food standard, yet biological hygiene control will be needed constantly.

본 연구의 목적은 한국어 어휘 교육을 위한 단어의 내용 구성을 체계적인 집합 안에서 어휘를 조직화하고 범주화하는데 있다. 연구 내용 을 정리하면 첫째, 한국어 교육 어휘를 위한 단어 내용을 단어의 어종과 의미관계에 따라 세분화하였다. 국제통용 한국어 교육 표준 모형(2011)의 기준에 따라 조사, 접사는 단어에 포함시키지 않았다. 둘째, 단어의 어종에 따른 어휘 교육은 원활한 구어 사용을 위한 고유어, 포괄적이고 전문적인 어휘 확장을 위한 한자어, 문화 접촉의 다변화로 증가 추세를 보이고 있는 외래어의 내용을 짚어 보았다. 셋째, 단어들의 의미파악을 쉽게 할 수 있도록, 단어의 의미관계에 따라 유의어와 반의관계(대립관계), 다의어와 동음관계, 상․하위어관계 등으로 나뉘어 어휘를 조직화하였다. 따라서 이를 통해 어휘가 가지고 있는 상관관계를 연계하여 한국어 교육에서의 단어 내용구성을 구축하고자 한다.

본 연구의 목적은 초급 한국어 교실 담화에서 교사가 사용하는 유형별 맞장구 양상을 살펴보는 것이다. 연구 내용을 정리하면 첫째, 교실 담화 속 교사의 언어적 맞장구를 담화표지(기본형, 긍정형, 전환형), 반복 및 대용표현(반복형, 대용형), 감정표현(놀람형, 아쉬움형, 기쁨형, 실망형)으로 나눈 후 사용 빈도와 기능을 알아보았다. 둘째, 가장 자주 사용된 것은 기본형과 반복형이었다. 기본형은 하강조의 ‘아’, ‘어’, ‘음’ 등으로 학습자의 선행 발화에 대한 경청과 동의를 표현했고 반복형은 상승조일 때는 학습자의 발화에 오류가 있음을, 하강조일 때는 학습자의 발화가 성공했음을 나타내는 기능을 했다. 셋째, 자칫 감정적인 오해를 살 수 있는 감정표현 맞장구는 거의 사용 되지 않았다. 본 연구는 녹음 자료를 바탕으로 해 비언어적 맞장구를 풍부하게 추출해내지 못했다는 한계점을 가지고 있지만 교실 담화에서 교사가 다양한 유형의 맞장구를 유의미하게 사용하고 있음을 알려 준데 의의가 있다.