• Applied Science and Convergence Technology
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• v.26 no.6
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• pp.208-213
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• 2017

Flexible opto-electronic devices are developed on the insulating layer deposited stainless steel (STS) substrates. The silicon dioxide ($SiO_2$) material as the diffusion barrier of Fe and Cr atoms in addition to the electrical insulation between the electronic device and STS is processed using the plasma enhanced chemical vapor deposition method. Noble silver (Ag) films of approximately 100 nm thickness have been formed on $SiO_2$ deposited STS substrates by E-beam evaporation technique. The films then were annealed at $650^{\circ}C$ for 20 min using the rapid thermal annealing (RTA) technique. It was investigated the variation of the surface morphology due to the interaction between Ag films and $SiO_2$ layers after the RTA treatment. The results showed the movement of Si atoms in silver film from $SiO_2$. In addition, the structural investigation of Ag annealed at $650^{\circ}C$ indicated that the Ag film has the material property of p-type semiconductor and the bandgap of approximately 1 eV. Also, the films annealed at $650^{\circ}C$ showed reflection with sinusoidal oscillations due to optical interference of multiple reflections originated from films and substrate surfaces. Such changes can be attributed to both formation of $SiO_2$ on Ag film surface and agglomeration of silver film between particles due to annealing.

• Journal of Science and Technology Studies
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• v.12 no.1
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• pp.45-78
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• 2012

What is a disaster? And what can science and technology studies tell us about it? There might be numerous definitions about disaster. In this article, we will posit that disaster is an incident when sociotechnical system actor-network broke down against the other force in their "trial of strength". This is a process that punctualized actor-network is depunctualized, and a status that readiness-to-hand of Being recedes while pesentness-at-hand of tool-being comes forward. Using the concept of disaster as a case study, we will consider how Latourian ontology overlaps with Heideggerian philosophy of technology. This STS approach which hasn't been previously studied might provide us with new theoretical framework that enables us to construe the assemblage of technoscience and nature-society in the field of PUS or NPSS.

• Journal of the Korean earth science society
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• v.23 no.2
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• pp.194-206
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• 2002

This article describes the major themes to change in historical and philosophical perspectives of science education that lead the US and Korean science curriculum reform movements since 1957. Inquiry teaching and criticism of teaching science as inquiry in the late 1950s and the 1960s, Science-Technology-Society (STS) Curricula, and Science Literacy and the 1980s science literacy crisis are discussed. In the US, three major curricular projects as responses to the scientific literacy crisis are exemplary such as the Project 2061 sponsored by the American Association for the Advancement of Science, the Project on Scope, Sequence, and Coordination (SS&C) initiated by the National Science Teachers Association (NSTA), and the National Science Education Standards (NSES) published by the National Research Council. To identify how each set of national content standards differ, we compared specific content standards related to the theory of plate tectonics in Earth and Space science in grades 9-12 over the three national standards: Benchmarks of AAAS, NSES of the NRC, and SS&C of the NSTA. Against this historical background of the US science education reform movements, the curriculum reform movements in Korea is briefly discussed. In general, Korean science curriculum reform movements have reflected and resembled the recommendations of the US reform movements. In addition, it is important to note that throughout the history of curriculum revision in Korea, there have been continuing pendulum swings between a theoretical, discipline-centered curriculum and a liberal, humanistic, and student-centered curriculum, which pays more attention to students in terms of their interest and psychological preparedness. In conclusion, the sixth and seventh national science curriculum revisions reflect rather a student-centered movement by reducing technical and sophisticated topics, taking constructivism learning theory into consideration, and adding more STS related topics.

• Journal of Ocean Engineering and Technology
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• v.21 no.5
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• pp.33-38
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• 2007

The welding methods have been applied in the most structural products from multi-field of automobile, ship construction and construction, and so on. The structure steel must have enough strength of structure. In this study, SS400 steel and STS304 steel were used to estimate the corrosion characteristics of the weld thermal cycle simulated HAZ. To evaluate the corrosion characteristics, also, the materials with two conditions were used in 3.5% NaCl. The one is to the drawing with diameter of ${\Phi}10$ and the other is to the residual stress removal treatment. The electrochemical polarization test and immersion test were carried out. From test results, corrosion potential, corrosion current density, weight loss ratio and corrosion rate were measured. In the kinds of SS400 steels, corrosion potential of weld thermal cycle simulated specimens after the heat treatment showed somewhat the direction of noble potential. And in the base metal to be drawing weight loss ratio and corrosion rate occurred higher than the other kinds. In the kinds of STS304 steels, the result of base metal to be drawing was similar to results of SS400 steels, too. Two kinds of $750^{\circ}C$ and $1300^{\circ}C$ of weld thermal cycle simulation after the heat treatment were rather higher than the other kinds in weight loss ratio and corrosion rate.

• Korean Journal of Medicinal Crop Science
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• v.21 no.5
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• pp.353-360
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• 2013

Korean ginseng (P. ginseng C. A. Meyer) is one of the most important medicinal plant in the world. Understanding genetic variability among the assortment of Korean ginseng is important for breeding. The aim of this study was to molecularly characterize Korean ginseng cultivar and breeding lines through the use of eight previously reported STS markers (MFGp183, MFGp130, MFGp110, UFGp74, UFGp163, MFGp108, MFGp81 and UFGp156). All STS markers produced interpretable electropherograms from 31 accessions consisting of 11 Korean ginseng cultivars and 20 breeding lines. When eight STS markers were combined, we identified to total 19 genetic patterns; in particular, nine cultivars (Chunpoong, Yunpoong, Gopoong, Gumpoong, Sunpoong, Sunone, Cheongseon, Sunhyang, Cheonryang) and 5 breeding lines (G08012, G04079, G04075, G08036, G04110) in ginseng samples can be discriminated from the others. Together with other available markers, these STS markers will contribute to the management of ginseng genetic resources and the protection of breeders' rights.

• Journal of Ocean Engineering and Technology
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• v.19 no.6 s.67
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• pp.64-71
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• 2005

The welding methods have been applied to the most structural products used in the automobile, ship construction, and construction. The structure steel must have sufficient strength of structure; However, the mechanical properties of the welded part changes when it is welded. Therefore, the stability or life of the structure may be affected by the changed mechanical properties. The mechanical properties of the welded part must be examined in order to ensure the safety of structure. In this research, the SS400 steel and the STS304 steel were used to estimate the mechanical properties of the HAZ by weld thermal cycle simulation. In this study, the materials were used to examine the weld thermal cycle simulation characteristic, under two conditions: the drawing with diameter of $\Phi$10 and the residual stress removal treatment. To examine the mechanical properties by the weld thermal cycle simulation, the tensile test was carried out in room temperature. The crosshead speed was lmm/min.

• Journal of The Korean Association For Science Education
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• v.39 no.6
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• pp.791-797
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• 2019

In this study, we investigated the influences of Integrated Science and Science Inquiry Experiment developed under 2015 Revised National Science Curriculum on students' interest in science, scientific attitude, views on STS, and the nature of science (NOS). 223 tenth graders in Seoul metropolitan area participated in this study. We conducted the survey prior to and after the Integrated Science and Science Inquiry Experiment course using same instruments and compared the results of the pre-test and post-test. The analyses of the results reveal that there were significant improvements in the scores of the pre- and post-test on the interest in science and scientific attitude. In the case of views on STS, there were significant improvements in items related to science research ethics, however there were no significant differences in the remaining items. Also, there were no significant differences in the scores of the pre- and post-test on views on NOS. On the bases of the results, we discuss educational implications and suggest further studies.

• Horticultural Science & Technology
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• v.17 no.6
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• pp.758-760
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• 1999

This experiment was carried out to investigate the effect of pretreatments and holding solutions on quality and vase life of cut 'Saphir' rose (Rosa hybrida L.). Pulsing with aluminum sulfate or NaOCl prolonged vase life held in HQS+sucrose+ethionine. Solution absorption held in distilled water were more increased than held in HQS+sucrose+ethionine. Holding solution with 8-hydroxyquinoline sulfate (HQS)+sucrose+ethionine increased fresh weight compared with distilled water except pulsing with STS+sucrose. Pulsing with aluminium sulfate delayed bent-neck held in HQS+sucrose+ethionine. Flower diameter and dry weight of petal held in HQS+sucrose+ethionine were more increased than held in distilled water except pulsing with STS+sucrose. There were no significance in Hunter color value 'L' and value 'a', but value 'b' was decreased held in distilled water.

• Corrosion Science and Technology
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• v.9 no.1
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• pp.39-47
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• 2010

Galvanic coupling between GECM(graphite epoxy composite material) and metallic materials can facilitate corrosion of metals and alloys because GECM is noble and electrically conductive. Galvanic corrosion is affected by many factors including metallic materials, area ratio, surface condition, and corrosivity. This work aims to evaluate the effect of area ratio on galvanic corrosion between GECM and several metals. In the case of glavanic coupling of carbon steel and Al to GECM, corrosion rate increased with increasing area ratio. Corrosion rate of sensitized STS 316S stainless steel decreased a little at an area ratio 1:1 but increased at an area ratio 30:1. It is considered to be due to that area ratio affects galvanic corrosion more in less corrosion resistant alloys. However, in case of STS 316 and Ti, galvanic coupling reduces corrosion rate by the formation of passive film.

• Molecules and Cells
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• v.38 no.4
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• pp.318-326
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• 2015

We previously reported that the SbROMT3syn recombinant protein catalyzes the production of the methylated resveratrol derivatives pinostilbene and pterostilbene by methylating substrate resveratrol in recombinant E. coli. To further study the production of stilbene compounds in E. coli by the expression of enzymes involved in stilbene biosynthesis, we isolated three stilbene synthase (STS) genes from rhubarb, peanut, and grape as well as two resveratrol O-methyltransferase (ROMT) genes from grape and sorghum. The ability of RpSTS to produce resveratrol in recombinant E. coli was compared with other AhSTS and VrSTS genes. Out of three STS, only AhSTS was able to produce resveratrol from p-coumaric acid. Thus, to improve the solubility of RpSTS, VrROMT, and SbROMT3 in E. coli, we synthesized the RpSTS, VrROMT and SbROMT3 genes following codon-optimization and expressed one or both genes together with the cinnamate/4-coumarate:coenzyme A ligase (CCL) gene from Streptomyces coelicolor. Our HPLC and LC-MS analyses showed that recombinant E. coli expressing both ScCCL and RpSTSsyn led to the production of resveratrol when p-coumaric acid was used as the precursor. In addition, incorporation of SbROMT3syn in recombinant E. coli cells produced resveratrol and its mono-methylated derivative, pinostilbene, as the major products from p-coumaric acid. However, very small amounts of pterostilbene were only detectable in the recombinant E. coli cells expressing the ScCCL, RpSTSsyn and SbROMT3syn genes. These results suggest that RpSTSsyn exhibits an enhanced enzyme activity to produce resveratrol and SbROMT3syn catalyzes the methylation of resveratrol to produce pinostilbene in E. coli cells.