• Proceedings of the Korean Vacuum Society Conference
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• 1994.06a
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• pp.134-134
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• 1994

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.215-222
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• 2008

Fifty-two Korean japonica rice cultivars were analyzed for leaf blast resistance and genotyped with 4 STS and 26 SSR markers flanking the specific chromosome sites linked with blast resistance genes. In our analysis of resistance genes in 52 japonica cultivars using STS markers tightly linked to Pib, Pita, Pi5(t) and Pi9(t), the blast nursery reaction of the cultivars possessing the each four major genes were not identical to that of the differential lines. Eight of the 26 SSR markers were associated with resistant phenotypes against the isolates of blast nursery as well as the specific Korean blast isolates, 90-008 (KI-1113), 03-177 (KJ-105). These markers were linked to Pit, Pish, Pib, Pi5(t), Piz, Pia, Pik, Pi18, Pita and Pi25(t) resistance gene loci. Three of the eight SSR markers, MRG5836, RM224 and RM7102 only showed significantly associated with the phenotypes of blast nursery test for two consecutive years. These three SSR markers also could distinguish between resistant and susceptible japonica cultivars. These results demonstrate the usefulness of marker-assisted selection and genotypic monitoring for blast resistance of rice in blast breeding programs.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.3
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• pp.372-379
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• 2013

In this study, we investigated the traits of the clad metals used in hot-rolled clad steel plates. We examined the sensitization and mechanical properties of STS 316 steel plate and carbon steel (A516) under the specific circumstances of post heat treatment and whether a weld was multilayered and thick or repeated because of repairs. The test conditions were as follows. The clad steel plates were butt-welded using FCAW/SAW, and the heat treatment was conducted at $625^{\circ}C$, for 80, 160, 320, 640, or 1280 min. The change in the corrosion resistance was evaluated in these specimens. In the case of the carbon steel (A516), as the heat treatment time increased, the annealing effect caused the tensile strength to decrease. The micro- hardness gradually increased and then decreased after 640 min. The elongation and contraction of the area increased gradually. An oxalic acid etch test and EPR test on STS316, a clad metal, showed a STEP structure and no sensitization. From the test results for the multi-layered and repair welds, it could be concluded that there is no effect on the corrosion resistance of clad metals. In summary, the purpose of this study was to suggest some considerations when developing on-site techniques and evaluate the sensitization of stainless steels.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.1
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• pp.22-29
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• 2018

The purpose of this study is to investigate the preliminary thermal performance of a plastic coated aluminum material(PCAM) plate heat exchanger. Plastic coating which has high corrosion resistivity and thermal conductivity can overcome corrosive weakness of aluminum material. The heat exchangers are modeled for STS316, Titanium and PCAM materials, and analyzed numerically using HTRI and ANSYS Fluent CFD softwares. The results show that PCAM heat exchanger is superior in heat transfer performance compared to existing materials. For chevron angle of $60^{\circ}$, thermal performances of Titanium and PCAM are higher by 12.2% and 48.9% when compared to STS316, respectively.

• Journal of The Korean Association For Science Education
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• v.35 no.4
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• pp.549-555
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• 2015

In this study, we investigated the influences of Integrated Science on the views of 10th graders with regards to the nature of science (NOS), STS, interest in science, and science aspiration, in order to explore the effects of Integrated Science developed under the 2009 Revised National Curriculum. Participants in this study were 214 10th graders in Seoul. The survey was administered at the beginning and at the end of the Integrated Science course. The analyses of the results revealed that there was no statistically significant difference in the scores of the pre-test and post-test on the NOS survey. However, the post-test scores of the tentativeness of scientific knowledge and the use of imagination, which are the sub-constructs of the NOS, were found to be significantly lower than the pre-test scores. There were no statistically significant differences in the frequencies of the responses to each item of the STS survey. The pre-test and post-test scores of the interest in science and the science aspiration were also not significantly different. The results indicated that Integrated Science did not have any impact on students' views on NOS, STS, interest in science, and science aspiration. Educational implications of these findings are discussed.

• Journal of Engineering Education Research
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• v.15 no.1
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• pp.61-71
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• 2012

The core issue of ethical problem solving in engineering is to understand what exactly happened and to define its nature. Problems often arise mostly in morally complex situations. Traditional philosophical theories usually focus on extreme conflicts of interest and suggest moral theory-centered problem solving methods. However, these methods are not only difficult to specifically apply to real situations, but also are likely to fail to deal with actual moral issues in engineering fields. This study aims to develop more desirable ethical problem solving methods, based on STS (Science and Technology Studies) and engineering ethics combined. First, we have examined the engineering ethics with implications of an STS perspective, then have analyzed traditional ethical problem solving methods in a critical point of view. This study will suggest a new ethical problem solving method named Matrix Guide, based upon those analyses. Specifically, this study classifies four stages of problem definition, analysis, solving, and feedback. Here, we focus on how to combine technological and non-technological factors in each stage, when we are facing morally complex situations in engineering sectors.

• Journal of Science and Technology Studies
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• v.16 no.2
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• pp.99-147
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• 2016

This paper critically reviews the previous discussion over public engagement with science and technology by Science and Technology Studies literatures with a focus on justification and acceptance. Recent studies pointed out that the "participatory turn" after the late 1990s was followed by confusion and disagreement over the meaning and agency of public engagement. Their discussion over the reproduction of the ever-present boundary between science and society along with so-called late modernity and post-normal science and sometimes through the very processes of public engagement draws fresh attention to the old problem: how can lay participation in decision-making be justified, even if we agree that privileging the position of experts in governance of science and technology is no longer justified? So far STS have focused on two conditions for participatory turn-1) uncertainties inherent in experts' ways of knowing and 2) practicability of lay knowledge. This paper first explicated why such discussion has not been logically sufficient nor successful in promoting a wide and well-thought-out acceptance of public engagement. Then the paper made a preliminary attempt to explain what new types of expertise can support the construction and sustainment of participatory governance in science and technology by focusing on one case of lay participation. The particular case discussed by the paper revolves around the actions of a civil organization and an activist who led legal and regulatory changes in wind power development in Jeju Special Self-governing Province. The paper analyzed the types of expertise constructed to be effective and legitimate during the constitution of participatory energy governance and the local society's support for it. The arguments of this paper can be summarized as follows. First, an appropriate basis of the normative claim that science and technology governance should make participatory turn cannot be drawn from the essential characteristics of lay publics-as little as of experts. Second, the type of 'expertise' which can justify participatory governance can only be constructed a posteriori as a result of the practices to re-construct the boundaries between factual statements and value judgment. Third, an intermediary expertise, which this paper defines as a type of expertise in forming human-nonhuman associations and their new pathways for circulations, made significant contribution in laying out the legal and regulatory foundation for revenue sharing in Jeju wind power development. Fourth, experts' conventional ways of knowing need to be supplemented, not supplanted, by lay expertise. Ultimately, the paper calls for the necessity to extend STS discussion over governance toward following the actors. What needs more thorough analysis is such actors' narratives and practices to re-construct the boundaries between the past and present, facts and values, science and society. STS needs a renewed focus on the actual sites of conflicts and decision-making in discussing participatory governance.

• Laser Solutions
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• v.12 no.3
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• pp.18-22
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• 2009

Experimental results for the laser shock peening of stainless steels, duplex stainless steel and STS304, for the enhancement of surface hardness are reported. A high power Nd:YAG laser (532 nm, 2nd harmonics) was used to irradiate the workpiece in water at the irradiances of 5, 10, $15\;GW/cm^2$. The surface of a workpiece was covered with Fe or Al foil for protection of the original surface and reduction of laser reflection. The laser pulse densities were varied from $25\;pulse/mm^2$ to $75\;pulse/mm^2$. In the case of the STS304, the surface hardness increased with increasing pulse density and the maximum increase of about 29% was achieved using Fe foil at $10\;GW/cm^2$ and $75\;pulse/mm^2$ conditions. The maximum increase in surface hardness of duplex stainless steel was about 8% at $10\;GW/cm^2$ and $75\;pulse/mm^2$ with also Fe foil. In the case of the Al foil, less increase of surface hardness was obtained, possibly due to the thermal expansion effect.

• Journal of Welding and Joining
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• v.30 no.2
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• pp.47-53
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• 2012

This paper aimed to study and understand the mechanical phenomena of thermal elasto-plastic behavior on the dissimilar butt joint (Al 6061-T6 and STS304) by TIG assisted Friction Stir Welding. Heat conduction and residual stress analysis is carried out using in-house solver. Two-dimensional results of the heat distribution and residual stresses in dissimilar joint for particular tool geometry and material properties are presented. The predicted stress along longitudinal direction in Al 6061-T6 and STS304 are approximately between 12-15% of their respective yield strengths. A comparison is made between experimentally measured and numerically predicted equivalent residual stress values.

• Journal of Welding and Joining
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• v.31 no.4
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• pp.54-61
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• 2013

This paper reports mild steel(SPHC) and stainless steel(STS304) sheets commonly used for railroad cars or commercial vehicles such as in the automobile and shipbuilding industries. The sheets are used in these applications, which are mainly fabricated using the shielded metal arc welding(SMAW) of dissimilar materials. It also reports an interesting application of Laser Induced Breakdown Spectroscopy(LIBS) in order to determine the elemental composition diffusion of SPHC and STS304. Arc blow produced by magnetic force during the electric arc welding prevents the formation from a sound weldment. In particular, the mechanical properties of the joint are influenced by not only by geometrical and mechanical factors but also the welding conditions for the arc welded joint. Therefore, the mechanical properties and performance are evaluated by performing a physicochemical component analysis. And they increase in accordance with content of elements and microstructure in mild steel. As results, appropriate range for magnetic fields could be achieved. Therefore, the effect of magnetic force in a butt weld of mild steel plates was investigated by comparing to the measured data.