• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.3
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• pp.204-209
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• 2004

Using STD11 and STS3 as a mold set, accuracy of a mold product could be improved by heat treatment. Results of Charpy impact test and measurement of retained austenite in STS3 and STD11, STD11 was superior than STS3 in effect of sub-zero treatment and stability of working and measure. Decrease of retain austenite by sub-zero treatment in STS3 did not occured.

• Journal of the Korean Chemical Society
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• v.50 no.2
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• pp.153-162
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• 2006

The purpose of this study was to analyze the STS (science-technology-society) contents in chemistry chapters of middle school science textbooks standardized by 7th national curriculum, and to investigate chemistry teachers' perception of STS education. This study was based on 8 essential elements in STS education suggested by Yager and 9 activities in SATIS (science and technology in society). The questionnaire and interview were used to investigate chemistry teachers' perception. As a result of this study, the average value of the STS contents in chemistry chapters of 7 kinds of middle school science textbooks was 22.4%, and the STS contents were preponderated to essential elements of science application and local and community relevance. And STS contents showed that science 2 textbooks were the most of all and in order of science 1 textbooks and science 3 textbooks. As a result of analysis by activities in SATIS, most activities were practice activity, problem-solving and decision making, and structured discussion. Chemistry teachers' perceptions of STS education were following. There were many responses that STS education was necessary for educational efficiency. On the other hand STS education was unnecessary because there were few effective teaching-learning method related with STS education. From these results, middle school science textbooks have to be complemented because 2 essential elements of the STS contents were preponderated in the science textbooks. And the teaching-learning method connected with STS education will have to be developed for the efficiency of STS education.

• Journal of the Korean Institute of Gas
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• v.9 no.1 s.26
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• pp.21-25
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• 2005

This paper was studied on the corrosion behavior of STS 304 for gas boiler in the condensed water, the electrochemical polarization test of STS 304 for gas boiler in the condensed water was carried out. And the corrosion behavior of STS 304 was considered. The main results are as following: 1) As corrosion environment is acidified from neutrality, the polarization resistance of STS 304 decreases and the corrosion potential is less noble. 2) The corrosion reaction mechanism of STS 304 is cathodic control. 3) As corrosion environment is acidified, the passive potential range of STS 304 decreases. Also, the passive current density of STS 304 increases.

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.90-96
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• 2002

The STS contents, emphasized in the 6th curriculum, in the chemistry textbooks(II) were analyzed. The STS contents in textbooks showed average value of 2.7%. The chapter of ‘chemical bond and compound' were included 3.8% of STS contents. And the chapter of ‘atomic structure and periodic table', ‘state of material and solution', ‘science of material', and ‘chemical reaction' contained 3.2%, 2.2%, 1.9%, and 1.9% of STS contents, respectively. When the STS contents were analyzed by STS topics of Piel, the results are as follows; 33.7% on effect of technological developments, 27.5% on environmental quality and utilization of natural source, 19.6% on human engineering, 13.8% on energy, and 5.4% on sociality of science. However, there were no topics on population, space research and national defense. When the STS contents were analyzed by student activities of SATIS, most of the activities were research and case study. There were few field activities of practical investigation, problem solving and decision making, research design and stimulation. There were no activities of role play.

• Biomolecules & Therapeutics
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• v.20 no.6
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• pp.556-561
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• 2012

Steroid sulfatase (STS) is responsible for the conversion of estrone sulfate to estrone that can stimulate growth in endocrine-dependent tumors such as prostate cancer. Although STS is considered as a therapeutic target for the estrogen-dependent diseases, cellular function of STS are still not clear. Previously, we found that tumor necrosis factor (TNF)-${\alpha}$ significantly enhances steroid sulfatase expression in PC-3 human prostate cancer cells through PI3K/Akt-dependent pathways. Here, we studied whether bacterial lipopolysaccharides (LPS) which are known to induce TNF-${\alpha}$ may increase STS expression. Treatment with LPS in PC-3 cells induced STS mRNA and protein in concentration- and time-dependent manners. Using luciferase reporter assay, we found that LPS enhanced STS promoter activity. Moreover, STS expression induced by LPS increased PC-3 tumor cell migration determined by wound healing assay. We investigated that LPS induced IL-6 expression and IL-6 increased STS expression. Taken together, these data strongly suggest that LPS induces STS expression through IL-6 pathway in human prostate cancer cells.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.1
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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.

• Journal of the Korean Society of Earth Science Education
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• v.5 no.1
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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.

• Journal of the Korean Society of Earth Science Education
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• v.3 no.1
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• pp.9-17
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• 2010

This study was carried out to examine the tendency about the relative importance of STS education of the 6th and 7th primary science curriculum. The results of the research are as follows. Primary science textbooks in the 6th curriculum, average 13.3% of the total pages was assigned to STS contents but it is increased to 24.2% in the science textbooks of the 7th curriculum. STS constituents of the 6th primary science textbooks come out orderly applications of scientific knowledge(47.1%), relevance of a community(40%), social problems and issues(11.8%). Of the 7th science textbooks, the contents about applications of scientific knowledge amount to 67.1% of the total STS constituent and relevance of a community(32.2%) rank behind it. The contents of other components are not enough. The 6th science textbooks contents about the effect of technological development amount to 35.3% of the total STS subject area, and environmental quality(20.0%), natural resource(15.2%), energy(11.8%), sociology of science(11.8%) ranks behind it. In the 7th science textbooks ranking is the effect of technological development(42.3%), natural resource(17.3%), energy(12.5%), sociology of science(12.5%), environmental quality(20.0%). There are few contents about population, human engineering and space research and national defense in the science textbooks.

• Journal of Power System Engineering
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• v.20 no.3
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• pp.43-50
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• 2016

The current study was carried to understand the immersion characteristics and mechanical properties of heat treated stainless steels. Stainless steels (STS310S, STS316L and STS347H) were thermally treated at temperature ranges from 480 to $720^{\circ}C$. Nominal stress was determined to be slightly different depending on the heat treatment temperature. The Cr concentration in STS310S was increased at the temperatures of 600 and $660^{\circ}C$, whereas the Cr concentration in STS316L and STS347H were almost constant regardless of heat treatment temperatures. Vickers hardness was found larger as a thermal treatment temperature was increased. Immersion tests of the stainless steels were also carried out in acidic solution and alkaline solution for 240 hours. Among three different stainless steels, the pitting was detected in the acidic solution, not in the alkaline solution. The pitting of STS347H was occurred more than STS310S and STS316L.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.9
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• pp.121-126
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• 2009

Stainless steel 316L (STS 316L) is widely used as a material of biopsy needle. However it has a side effect that tissue can be damaged by electrochemical operation between tissue and STS 316L. Many studies have been made on the ceramic coating of biopsy needle to reduce the side effect. In this study, STS 316L was coated with three bioceramics, $Al_2O_3$, $SiO_2$ and $ZrO_2$ using a RF magnetron sputtering method. The effects of ceramic coating on the electrical conductivity and coating strength of ceramic-coated STS 316L were investigated. The results showed that the electrical conductivity of ceramic-coated STS 316L was much lower than that of uncoated STS 316L. The coating strength of $ZrO_2$-coated STS 316L was 30% and 70% higher, respectively than those of $Al_2O_3$-coated STS 316L and $SiO_2_3$-coated STS 316L.