• Journal of Fisheries and Marine Sciences Education
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• v.19 no.1
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• pp.84-90
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• 2007

This paper was studied on the electrochemical corrosion characteristics of weld zone for refrigerating and heating systems pipe. Austenitic stainless steel is widely applied to various fields of industry, because it is good to corrosion resistance and mechanical properties. But STS 304 is reliable to sensitization by heat cycle on welding. Therefore, in this study, electrochemical polarization test of STS 304 steel pipe manufactured by arc welding in tap water was carried out. And then polarization resistance behavior, uniform and local corrosion behaviors of base metal(BM), weld metal(WM) and heat affected zone(HAZ) for STS 304 pipe were investigated. The corrosion current density of STS 304 steel pipe is high in order of BM(153nA/cm2) < WM(614nA/cm2) < HAZ ($1.675{\mu}A/cm2$). The pitting potential of HAZ(238mV/SCE) for STS 304 is lower than BM(1206mV/SCE) and WM(369mV/SCE). Therefore, the local corrosion like pitting corrosion, galvanic corrosion and crevice corrosion of HAZ for STS 304 is more sensitive than BM and WM.

• Journal of the Korean Chemical Society
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• v.49 no.2
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• pp.215-223
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• 2005

• Journal of The Korean Association For Science Education
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• v.24 no.6
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• pp.1143-1157
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• 2004

The purpose of this study was to develop HS-VOSTS(High School Students' Views On Science-Technology-Society), which is an instrument that monitors high school students' views on STS. For this study, 23 multiple-choice items were developed on four categories. First, a categorial scheme was constructed. The categorial scheme was based on many instruments that evaluate students' understanding on STS, literature review, and STS learning goal that many researchers had asserted. Second, the multiple-choice items were developed. The development of the items was carried out through four steps. In the first step, some pairs of statement on each subordinate category were formed. Next, the student statement questionaries which were based on the pairs of statement were responded by 772 students. In the second step, the response written by the students were analyzed to common viewpoints and the first multiple-choice items were constructed. In the third step, the semistructured interview with 28 high school students was implemented and the second multiple-choice items were constructed. In the fourth step, the final version of the instrument was developed through the analysis of the students' response on the second multiple-choice items. HS-VOSTS is an useful instrument for monitoring students' beliefs and viewpoints on STS topics. The results of the students' responses to HS-VOSTS items reflect the students' own thoughts directly. These results will give some implications for the curriculum developers, the authors of text books and the educational policy makers as well as the teachers.

• Journal of The Korean Association For Science Education
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• v.17 no.4
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• pp.359-371
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• 1997

The purpose of this investigation was to examine and compare pre-service and in-service secondary tearchers' beliefs about STS, particulary beliefs about the nature of science and technology and their interaction within society. For this study, a belief was defined as something that people believe and accept as true. Instrument used in this investigation was empirically developed multiple-choice instrument entitled the Tearchers' Belief about Science - Technology - Society(TBA-STS) by Peter A. Rubba and William L. Harkness. The result of survey showed that large percentages of the preservice and in-service secondary science teachers in the two samples held misconception about the nature of science and technology and their interactions within society. And there was no apparent difference between the samples on their beliefs about STS interactions.

• Journal of The Korean Association For Science Education
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• v.18 no.4
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• pp.539-544
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• 1998

The consistency and balance of objectives by objective domains in units, sub-units and instructional units were investigated. The 6th elementary biology curricular teaching guidebooks were analysed. Domains of objectives are cognitive, inquiry process, instrumental skill, creative, affective and STS. Cognitive objectives were most dominant in all units, sub-units and instructional units. But no objective for creative domain were suggested. In unit and sub-unit, proportions of objectives were cognitive, inquiry process, affective, instrumental skill and STS domains in order. Objectives for cognitive and inquiry process domains were more than others in instructional units, Except cognitive and inquiry process domains, objectives for the others were not consistent in all units, sub-units and instructional units. Especially, the percentages of objectives for affective domain decreased in units, sub-units and instructional units orderly. These resulted from teaching objective domains categorized formally, Thus, it is necessary to develope curriculum and textbook to be consistent and balanced with objective domains and reflect upon the characteristics of them.

• Journal of the Korean Society of Earth Science Education
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• v.4 no.1
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• pp.66-73
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• 2011

This study aims to compare and analyze the types of teaching-learning activities, themes and percentage of STS contents in the area of "The Earth and the Universe" in elementary science subject following the 7th Curriculum and 2007 Revised Curriculum, identifying how STS education has changed and their features. First, the number of pages where STS appears in the 2007 revised science textbook has increased over 10% compared to the that of the 7th curriculum. In particular, the number of pages in the 5th and 6th graders increased substantially to 15% and 34%, respectively. Second, as a result of analysis on components of STS, 'applications of science', 'local and community relevance', 'social problem and issues', 'evaluation concerned fir getting and using information' were obtained in the order named for the 7th curriculum; while 'applications of science', 'local and community relevance', 'career awareness' and 'social problem and issues' were obtained in the order named for 2007 revised curriculum. Third, with regard to the analysis on theme areas, the 7th curriculum was found to cover the theme on use of natural resources most frequently, followed by environmental problem, while 2007 revised curriculum to cover environmental problem and effects of technical development most frequently, followed by space development and use of natural resources. Fourth, in the area of STS teaching activities, 'investigation activity' showed highest percentage in 7th curriculum, followed by 'analysis of data', and 'research design', while 'analysis of data' showed highest frequency of appearance, followed by "investigation activity' and 'actual activities' and 'research design' in the order named in 2007 revised curriculum, showing that the area of 'analysis of data' and 'actual activities' increased substantially compared to the 7th curriculum.

• Journal of Korean Elementary Science Education
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• v.18 no.1
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• pp.29-39
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• 1999

The purpose of this investigation was to examine and compare pre-service and in-service elementary school teachers' beliefs about Science-Technology-and Society (STS), particularly beliefs about the nature of science and technology, their interaction within society, and the epistemology of science. Large percentage of pre-service and in-service elementary school teachers were understood to perceive as follows : 1. they regarded the science as 〃Knowledge scheme aiming content'and technology as 'skill for solution of actual problems'. 2. they revealed themselves to perceive tat science/ technology influence our lives through new terms and ideas, that science/ technology is affected by governmental policies and that all the people concerned including scientist and technologist should participate in the course of decision making. 3. they perceived that scientist perform their studies by characteristic abilities and that the studies are affected by their religious viewpoint. Moreover, they were understood to perceive that scientific knowledge are constructed through social interaction. 4. they perceived that scientist discover and develop scientific laws by scientific methods such as verification and certification, and that those scientific laws could be changed later.

• Journal of The Korean Association For Science Education
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• v.11 no.2
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• pp.87-101
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• 1991

Science-Technology-Society curricula have been developed in several countries for the last 20 years. Those curricula were focused on social aspects of science, i.e., value-laden knowledge and scientific enterprise, and society-related scientific and technological issues, i.e., energy, pollution, natural resources. The major teaching models employed in those curricula were problem solving and decision making, which required the following teaching techniques: teacher as a manager, small group discussion, controversy as a motivational force for substantive learning, and sufficient factual information into the discussion. Further researches are to be made to ascertain whether or not the expectations of the curricula might be realized in practice. It was shown that most Korean biology teachers considered the STS-related goal of science education as more important than the other goals. Based upon the findings, some recommendations for development of Korean STS curriculum were made as follows: 1. The contents of the STS curricula are to be organized with the integrated mode; 2. The major teaching models throughout the contents are to be problem solving and decision making. These are considered to provide students with the opportunities to involve in debates on practical issues and to draw consensus from them; 3. Some degree of flexibility should be provided on teachers' implementation of the curriculum in terms of contents, teaching techniques etc.; 4. To increase the practicality of the curriculum, teachers should be involved in the development of the curriculum and the relevant research; and 5. Contents to be included in STS curriculum were suggested by some science educators, but the more systematic study is required in this respect.

• Journal of Korean Elementary Science Education
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• v.24 no.1
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• pp.30-42
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• 2005

In this study, we developed an elementary science performance assessment material on STS theme, especially the respiration. The material is constituted with 3 components, which are performance task, students' response format and scoring system, and it also has various objective domains such as applying science knowledge, improving science attitude, using ICT, communicating and reflective thinking. It offers teachers a tool by which they can assess students' abilities on a whole. The task is made with the motivation-evoking content of 'No Smoking'. It is constructed on the activity of writing a letter to his/her father not to smoke. The students' response format is made by problem solving process, and the scoring system is matched with the steps of students' response. The material involves several theoretical backgrounds and the strengths of performance assessment. In addition, due to the detailed students' format and scoring system, it can be used practically in elementary science classroom.

• Journal of Fisheries and Marine Sciences Education
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• v.18 no.1
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• pp.58-64
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• 2006

In order to examine the effect of humidity on hydrogen embrittlement of STS 444 weld zone for boiler with dry and wet welding conditions, this paper was carried out the accelerated hydrogen osmosis test and the electrochemical Tafel polarization test. In 0.5M $H_2SO_4$ + 0.01M $As_20_3$ solution, this test is added to load of $1400kg/cm^2$ together with hydrogen osmosis by current of $50 {mA/cm^2}$ for 60 min.. The electrochemical Tafel polarization test was carried out in 0.5M $H_2SO_4$ + 0.01M $As_20_3$ solution. Therefore, the effect of humidity on hydrogen embrittlement of STS 444 was considered. The main results are as following: On the basis of hydrogen embrittlement mechanism, that is, integrated electrochemical polarization characteristics with the established mechanism of hydrogen embrittlement, the reduction rate of corrosion current density of weld zone in the wet weld condition is larger than in the dry condition. We can nondestructively predict the degree of hydrogen embrittlement of STS 444 weld zone for boiler through the reduction rate of electrochemical corrosion current density.