• 한국초등과학교육학회지:초등과학교육
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• 제31권2호
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• pp.154-163
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• 2012

In this study, we analyzed the proportions of STS content, components, topics, and types of the activities of STS content in the elementary science textbooks developed under the 2007 Revised National Curriculum. The analyses of the results revealed that the percentage of STS content included was 15.9% by the number of pages, and 13.5% by the lesson hour. By the components of the STS content, the proportion of 'application of science', 'science-technology and our life' and 'social problems and issues' were large. Most STS topics were related to the 'effects of technological developments' and 'environmental issue', and the topics of 'family and population' and 'human engineering' were few. By the types of the activities, reading was the most, and investigation and writing were also found. Compared with those of the science textbooks developed under the 7th National Curriculum, the variety of components of the STS content increased, but the proportion of STS content and the variety of activities of STS content decreased in the science textbooks developed under the 2007 Revised National Curriculum.

• 한국지구과학회지
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• 제22권4호
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• pp.259-267
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• 2001

이 연구의 목적은 STS 학습 프로그램의 적용이 실업계 고등학생의 과학과 관련된 태도에 미치는 효과를 찾는 것이다. 이를 위하여 고등학교 ‘공통 과학’ 중 지구과학 영역을 선택하였고, STS 학습 프로그램을 1년 간 경북 구미시의 실업고등학교 2학년 여학생 6개반(318명)을 대상으로 하여 교수-학습에 적용하였다. 이런 과정에서 STS 학습 프로그램에 필요한 학습 보조 자료들도 개발하여 활용하였다. 그 결과 STS 학습 프로그램의 적용 후가 적용 전보다는 학생들의 과학 성취도 및 태도에 긍정적인 효과를 나타낸 것으로 나타났다.

• 한국산업융합학회 논문집
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• 제25권6_2호
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• pp.987-992
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• 2022

STS 410, a representative martensitic stainless steel, contains 13 % chromium and is used for building materials, automobile parts, office equipment, kitchen utensils, and tableware. In general, the strength of STS 410 changes by the carbon content, and STS 410 of low carbon has excellent toughness and high carbon has excellent abrasion resistance. In this study, a fatigue test was performed on the STS 410 material to evaluate the exact fatigue limit and to evaluate the behavior of the material against fatigue. In addition, the effect on burnishing, a kind of plastic processing that creates a smooth surface by pressing a ball or roller on the inner and outer surfaces of the material was evaluated. The fatigue limit was 509 MPa for the STS 410 material, and the result was 54.5 % of the tensile strength. The fatigue limit was 542 MPa for the specimen of diamind burnished STS 410 material, and it was 58.5 % of the tensile strength.

• 대한금속재료학회지
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• 제46권11호
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• pp.708-712
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• 2008

The influence of high temperature gas nitriding (HTGN) in STS347 and STS310S steels was experimentally investigated. The HTGN was carried out at $1,050^{\circ}C{\sim}1,150^{\circ}C$ for 10 hrs in a gaseous atmosphere containing $1kg/mm^2$ of nitrogen. After HTGN, fine precipitates of $Cr_2N$ and NbN appeared in austenite on the surface of STS 347, while nitrogen pearlite, which was layeredof $Cr_2N$ and austenite alternatively, appeared in austenite on the surface of STS 310S. The surface hardness of HTGN-treated, STS 347 and STS 310S specimens was 250~360 Hv and 270~400 Hv, respectively, depending on the temperature of HTGN. The nitrogen content was analyzed 1.4 wt% and 1.6 wt% at the surface layer of STS 347 and STS 310S steels, respectively. In addition, an improvement in the corrosion resistance of HTGN treated specimens was observed.

• 대한지구과학교육학회지
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• 제5권1호
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• pp.42-50
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• 2012

The Purpose of this study was to analyze STS contents in elementary school science textbooks according to 6th, 7th and revision 2007 national curriculum. The contents of STS were analyzed by the STS elements of Yager and the STS topics of Piel's standard. Major findings from the analyses are as follows: (1) The STS contents in the science textbooks of the 6th curriculum took up 13.7% and increased to 18.3% in the 7th and 19.0% in the revision 2007, which showed that the textbooks followed the goal of the national curriculum faithfully. (2) Based on the STS elements by Yager's standard, most of STS content is focused on 'Application of science', 'Social problems and issues' and 'Local and community relevance'. (3) Based on the STS topics by Piel's standard, most of STS contents are focused on 'Effect of technological development' and 'Society of science'. These results indicate that recent STS education trends are reflected on the 6th, 7th and revision 2007 textbooks well. However, it is suggested that some improvement is needed, such as diversification of topic.

• 대한화학회지
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• 제49권2호
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• pp.215-223
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• 2005

• 한국과학교육학회지
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• 제25권3호
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• pp.336-345
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• 2005

본 연구는 국내외 주요 과학관의 전시물에 포함된 STS 관련 내용을 분석하여 대중들에게 과학과 기술, 사회의 관계 및 최신 과학 기술의 윤리적 문제들을 교육시키기 위해 어떠한 노력을 하고 있는지 살펴보았다. 연구 결과, 각 과학관들은 최신 과학기술을 소개하고, 과학과 기술, 사회의 관계 및 과학기술과 관련된 윤리적 측면에 관련된 문제를 다양한 방법을 통하여 대중들에게 소개하고 있다. 아직까지 우리나라의 과학관들은 최신 과학 기술에 대하여 개념적인 설명이나 관람객의 흥미를 끌 만한 단편적인 사건과 현상의 소개, 과학 기술의 발전으로 인한 긍정적인 측면을 보여주는 경우가 대부분이어서 관람객들로 하여금 과학 기술에 대한 왜곡된 이미지를 갖게 할 수 있다는 문제점을 지니고 있다. 우리나라의 과학관들은 외국 과학관의 대중의 과학적 소양을 증진시키기 위한 다양한 과학관 교육 내용과 방법에 대해 조사 연구함으로써 우리나라 상황에 적절한 STS 관련 소재를 발굴하고 이를 과학관을 통하여 교육하기 위한 다양한 방법을 개발해야 할 것이다.

• 열처리공학회지
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• 제20권6호
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• pp.311-317
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• 2007

This study examined the phase changes, nitride precipitation and variation in mechanical properties of STS 304, STS 321 and STS 316L austenitic stainless steels after high temperature gas nitriding (HTGN) at temperature ranges from $1050^{\circ}C\;to\;1150^{\circ}C$. Fine round type of $Cr_2N$ nitrides were observed in the surface layers of 304 and 316L steels, even more in STS 321. Additionally, square type of TiN was found in STS 321 austenitic matrix too. As a result of many precipitates in the surface layer of the STS 321, it was seen $370{\sim}470Hv$ hardness variation depending on the HTGN treatment conditions, and interior region of austenite represented 150Hv. The surface hardness value of STS 304 and STS 316L showed $255{\sim}320Hv$, respectively. The nitrogen content was shown 0.27, 1.7 and 0.4% respectively at the surface layers of the STS 304, STS 321 and STS 316L. After the HTGN it was shown the improvement of corrosion resistance of the STS 321 and STS 316L compared with solution annealed steels in the solution of 1N $H_2SO_4$ whereas the STS 304 was not.

• 한국초등과학교육학회지:초등과학교육
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• 제21권2호
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• pp.289-296
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• 2002

본 연구의 목적은 제 7차 교육과정에 의한 초등학교 과학 교과서에서 STS 내용을 분석하는 것이다. 연구의 주요 결과는 다음과 같다: (1) STS 내용의 포함 비율은 쪽수의 측면에서는 26%, 수업 시수의 측면에서는 40%이었다. '에너지'와 '물질' 영역에서의 비율이 높고 학년별 비교에서는 5학년 교과서에 포함된 내용이 상대적으로 적었다. (2) 대부분의 STS 주제는 기술이나 사회보다는 과학과 관련 있었다. (3) STS 내용이 한 시간 수업의 전체 과정에서 사용되는 경우도 많았다. (4) 대부분의 활동이 '그룹활동'과 '실험.관찰'에 해당하였고 '역할놀이, '현장견학', '인터뷰' 등의 활동은 거의 없었다. 이러한 결과는 개정된 교과서가 최근의 STS 교육사조를 잘 반영한다는 것을 의미한다. 그러나 STS 주제나 활동유형을 보다 다양화시키는 등 일부 측면에서의 개선이 요구됨을 시사한다.

• 한국대기환경학회지
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• 제8권1호
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• pp.7-12
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• 1992

This study was conducted to determine the effectiveness of silver thiosulfate(STS) in reducing $O_3$ injury to tomato plants(Lycopersicon esculentm Mill. 'Pink Glory'). Two days prior to $O_3$ fumigation, plants were given a foliar spray of STS solution at concentrations of 0, 0.2, 0.4, 0.6 mM contained with 0.05% Tween-20. STS concentrations below 0.6 mM were significantly effective in providing protection aginst $O_3$ exposure(16 h at 0.3 ppm). STS reduced leaf injury rate, defoliation of cotyledons, ethylene production and degree of epinasty induced by $O_3$ injury. STS slightly increased ethylene production in non-$O_3$-fumigated plants, but changes of chlorophyll content and transpiration rate on a whole plant basis were not observed. In $O_3$-fumigated plants, STS treatment reduced chlorophyll destruction but did not affect transpiration rate. STS treatment seemed not to affect peroxidase(POD) and superoxide dismutase (SOD) activity in non-fumigated plants but reduced increasing activity of POD by $O_3$ fumigation. However, such an effect as above was not found in SOD activity. Even though enzymatic protection effects were not confirmed, the fact that reduction of acute injury rate was attained for 16 h fumigation indicates that the phytoprotective effects of STS are not necessarily related to blocking the action of strees-induced-ethylene as an anti-ethylene agent.