• Journal of Science and Technology Studies
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• v.2 no.1 s.3
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• pp.107-134
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• 2002

Recently, society's relationship with science is in a critical phase. There was never a time when the issues involving science were more exciting. Many people are deeply uneasy about the safety and ethics of bio-technology. On the other hand, this could be interpreted as a dynamic process in which a new relationship between science and public is reshaping. And in this new relationship citizen participation in science is not a option but a necessity. This article is a case study of 1970's re-combinant DNA debate. Early 1970's bio-technology saw the emergence of an enormously powerful new methodology, recombinant DNA technology. But, at the outset, this technology posed many potential dangers. Concern over possible hazards prompted hot debates and conflict between leading scientists and community, In this process Cambridge Laboratory Experiment Lion Review Board (CERB) is organized by Cambridge City Coun il for assessing the possible risk of recombinant DAN technique. This is one of the first citizen-initiated participation movement in bio-technology. And the debates has come to be a principal focus for many of the most important questions concerning citizen participation in science. This study make a attempt to analyze CERB case. In conclusion, we can confirm the possibility of civil participation in science policy making and decision making from CERB case study. Still, we also realize the limit of CERB case.

• Journal of the Korean Magnetics Society
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• v.25 no.5
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• pp.156-161
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• 2015

The electronic structures of the potential candidate semiconductor nanoparticles for dye-sensitized solar cell (DSSC), such as $ZnSnO_3$ and $Zn_2SnO_4$, have been investigated by employing X-ray photoemission spectroscopy (XPS). The measured X-ray diffraction patterns show that $ZnSnO_3$ and $Zn_2SnO_4$ samples have the single-phase ilmenite-type structure and the inverse spinel structure, respectively. The measured Zn 2p and Sn 3d core-level XPS spectra reveal that the valence states of Zn and Sn ions are divalent (Zn 2+) and tetravalent (Sn 4+), respectively, in both $ZnSnO_3$ and $Zn_2SnO_4$. On the other hand, the shallow core-level measurements show that the binding energies of Sn 4d and Zn 3d core levels in $ZnSnO_3$ are lower than those in $Zn_2SnO_4$. This work provides the information on the valence states of Zn and Sn ions and their chemical bonding in $ZnSnO_3$ and $Zn_2SnO_4$.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.4
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• pp.375-382
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• 1999

In order to investigate the contamination characteristics of the heavy metals in the mine tailings of abandoned gold mine and its surrounding agricultural soils, a sequential extraction procedure of increasing reactivity in the dissolution processes of the heavy metals(Cd, Cu, and Pb) which were associated with solid and/or solution phase in soils was attempted to partition into six particulate fractions : exchangeable, bound to carbonate, bound to Fe-Mn oxides, bound to organic matter, residual, and soluble. Among indigenous heavy metals in the mine tailings, Pb was the most abundant and Cu and Cd were followed by. Fractionation result of Pb obtained from the triplicate samples of the mine tailings were in the order of Fe-Mn oxide> Carbonate> Residual> Organic> Exchangeable> Soluble, while Wolgok series were Exchangeable > Fe-Mn oxide > Carbonate> Organic> Residual> Soluable. However the other heavy metals studied were not followed this trend. The fractionation results of mine tailing and agricultural soils demonstrated that different geochemical fractions were operationally defined by an extraction sequence that generally followed the order of decreasing solubility. Therefore potential mobility and bioavailability of heavy metals as toxic pollution sources can be evaluated when studying the pollution levels of heavy metals in soils.

• Journal of Technology Innovation
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• v.28 no.4
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• pp.127-150
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• 2020

The World Health Organization (WHO) declared the third pandemic in history after the Hong Kong flu and swine flu. The outbreak of Corona 19 dramatically reduced exchanges between countries, while rapid contagion created a time gap in economic fluctuations by country. In January 2020, the trade dispute between the US and China entered into a consensus phase, but the economic decoupling phenomenon caused by Corona 19 made it difficult for China to balance trade with the US and made it difficult to comply with the terms of the trade dispute agreement between the US and China. President Trump attributed the responsibility for the spread of Corona 19 to China, and pointed out that the cause of the economic downturn was the infringement of Chinese trade secrets and illegal copies, and protectionism arose. As a result, China protested fiercely, and the conflict with the United States deepened. The US has declared trade sanctions on Huawei and SMIC, which are key companies in China's semiconductor industry, and is predicting the risk of a disconnection of the semiconductor value chain between the US and China. The separation of the value chain of the semiconductor industry has the potential to have a big impact on the semiconductor industry, a structure that is highly specialized and monopolized by certain countries and companies in the value chain. This paper aims to deal with the risk of disconnection in the semiconductor value chain between the US and China reignited by Corona 19, the impact and change of the global semiconductor industry value chain, and the response strategies of Korean semiconductor companies.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.343-349
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• 2021

The rhizomes of Cnidium officinalis were extracted in aqueous MeOH, and the concentrate was fractionated via systematic solvent fractionation to EtOAc, n-BuOH, and aqueous fractions. The repeated column chromatography of EtOAc and n-BuOH fractions using silica gel, octadecyl silica gel, and Sephadex LH-20 as stationary phase to afford five lipids. They were identified to be methyl linoleate (1), linoleic aicd (2) 6-linoleoyl-𝛼-D-glucopyranosyl 𝛽-D-fructofuranoside (3), 1-linolenoyl-3-(𝛼-D-galactopyranosyl (1→6)-𝛽-D-galactopyranosyl) glycerol (4), and 1-linoleoyl-3-(𝛼-D-galactopyranosyl (1→6)-𝛽-D-galactopyranosyl) glycerol (5) on the basis of spectroscopic data such as IR, MS, and Nuclear magnetic resonance (NMR). Compounds 1 and 3-5 were isolated for the first time from this plant in this study. The NMR data of fatty acids 1 and 2 reported in literatures are different each other. Authors identified the NMR data without ambiguity. Compound 3, a conjugate of sucrose and fatty acid, and compounds 4 and 5, digalactosyl monoglyceride, are very rarely occurred in natural source. Through the immune enhancement and anticancer activity of the reported lipid compounds, the potential as various pharmacologically active materials of Cnidium officinalis rhizome can be expected.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3367-3378
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• 2021

The design phase and safety assessment of Generation IV liquid metal-cooled fast reactors calls for the improvement of fuel pin performance codes, in particular the enhancement of their predictive capabilities towards uranium-plutonium mixed oxide fuels and stainless-steel cladding under irradiation in fast reactor environments. To this end, the current capabilities of fuel performance codes must be critically assessed against experimental data from available irradiation experiments. This work is devoted to the assessment of three European fuel performance codes, namely GERMINAL, MACROS and TRANSURANUS, against the irradiation of two fuel pins selected from the SUPERFACT-1 experimental campaign. The pins are characterized by a low enrichment (~ 2 wt.%) of minor actinides (neptunium and americium) in the fuel, and by plutonium content and cladding material in line with design choices envisaged for liquid metal-cooled Generation IV reactor fuels. The predictions of the codes are compared to several experimental measurements, allowing the identification of the current code capabilities in predicting fuel restructuring, cladding deformation, redistribution of actinides and volatile fission products. The integral assessment against experimental data is complemented by a code-to-code benchmark focused on the evolution of quantities of engineering interest over time. The benchmark analysis points out the differences in the code predictions of fuel central temperature, fuel-cladding gap width, cladding outer radius, pin internal pressure and fission gas release and suggests potential modelling development paths towards an improved description of the fuel pin behaviour in fast reactor irradiation conditions.

• Journal of Broadcast Engineering
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• v.26 no.4
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• pp.409-418
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• 2021

Conformal coating is a technology that protects PCB(Printed Circuit Board) and minimizes PCB failures. Since the defects in the coating are linked to failure of the PCB, the coating surface is examined for air bubbles to satisfy the successful conditions of the conformal coating. In this paper, we propose an algorithm for detecting problematic bubbles in high-risk groups by applying image signal processing. The algorithm consists of finding candidates for problematic bubbles and verifying candidates. Bubbles do not appear in visible light images, but can be visually distinguished from UV(Ultra Violet) light sources. In particular the center of the problematic bubble is dark in brightness and the border is high in brightness. In the paper, these brightness characteristics are called valley and mountain features, and the areas where both characteristics appear at the same time are candidates for problematic bubbles. However, it is necessary to verify candidates because there may be candidates who are not bubbles. In the candidate verification phase, we used convolutional neural network models, and ResNet performed best compared to other models. The algorithms presented in this paper showed the performance of precision 0.805, recall 0.763, and f1-score 0.767, and these results show sufficient potential for bubble test automation.

• Food Engineering Progress
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• v.15 no.4
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• pp.398-403
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• 2011

A dielectric barrier discharge plasma (DBDP) treatment system was fabricated and the optimum operating conditions for the plasma generation were determined in order to explore the potential of cold plasma as a non-thermal proessing technology. The microbial inactivation performance of the system was also evaluated against Staphyloocus aureus. The system consisted of power supply, transformer, electrode assembly and sample treatment plate. The input power was 220 V single phase AC and amplified to 10.0-50.0 kV on a transformer. A pulsed sine wave of frequency 10.0-50.0 kHz was introduced to the electrode embedded in ceramic as a dielectric barrier material in order to generate plasma at atmospheric pressure. Higher currents and consequently greater power were required for the plasma generation as the frequencies increased. A homogeneous and stable plasma was generated at currents of 1.0-2.0, and frequencies of 32.0-35.3 kHz. The optimum electrode-gaps for the plasma generation were 1.85 mm without loaded samples. More power was consumed as the electrode-gaps increased. The practically optimum electrode- gap was, however, 2.65 mm when samples were treated on slide-glasses for microbial inactivation. The maximum temperature increase after 10 min treatment was less than 20$^{\circ}C$, indicating no microbial inactivation effect by heat and thereby insuring a non-thermal method. The DBDP inactivation effect against Staphyloocus aureus increased linearly with treatment time up to 5 min, but plateaued afterward. More than 5 log reduction was achieved by 10 min treatment at 1.25 A.

• Journal of Life Science
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• v.29 no.4
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• pp.447-454
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• 2019

Fat accumulation in adipocytes occurs through the process of adipogenesis in which preadipocytes differentiate into adipocytes. Obesity is a metabolic disorder caused by excessive accumulation of fat in the body, which increases the incidence of cardiovascular diseases, hypertension, type 2 diabetes, hyperlipidemia, and various cancers. Recently, inhibition of adipocyte differentiation was shown to be a potential antiobesity strategy. In this study, the inhibitory effect of dichloromethane fractions from Illicium verum Hooker fil. water extract on the differentiation of 3T3-L1 preadipocytes to adipocytes was investigated. Dichloromethane fractions from I. verum Hooker fil. significantly inhibited adipocyte differentiation when applied during the adipocyte differentiation process, as assessed by measuring fat accumulation using Oil-red O staining. In addition, dichloromethane fractions from I. verum Hooker fil. reduced important adipogenic transcription factors, such as CCAAT/enhancer binding protein ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$, and peroxisome proliferator activated receptor ${\gamma}$ ($PPAR{\gamma}$). The expression of FAS and LPL, which are terminal differentiation markers of mature adipocytes, was also reduced in the 3T3-L1 adipocytes treated with dichloromethane fractions from I. verum Hooker fil. In addition, the treatment significantly inhibited mitotic clonal expansion, which is essential for adipocyte differentiation, by arresting the G1 phase of the cell cycle. Taken together, these results suggest that dichloromethane fractions from I. verum Hooker fil. may be a natural material with antiobesity effects.

• Clean Technology
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• v.25 no.2
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• pp.123-128
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• 2019

$Bi_2MoO_6$ catalysts were successfully synthesized using ethylene glycol monomethyl ether (EGME), glycerol (GL), ethylene glycol (EG), and water as solvents by a conventional hydrothermal method. The synthesized catalysts were characterized by XRD, DRS, BET, SEM, and PL, and we also investigated the photocatalytic activity of these materials for the decomposition of Rhodamin B under visible light irradiation. The XRD results revealed the successful synthesis of 12-18 nm, well-crystallized ${\gamma}-Bi_2MoO_6$ crystals with an Aurivillius structure regardless of solvent. In addition, the $Bi_2MoO_6$ catalysts prepared below $140^{\circ}C$ showed an amorphous phase; however, those prepared above $160^{\circ}C$ showed well-crystallized ${\gamma}-Bi_2MoO_6$ crystals. All the catalysts have a similar absorption spectrum from the ultraviolet region up to the visible region less than 470 nm. This result suggests that all the $Bi_2MoO_6$ catalysts are potential visible-light-driven photocatalysts. The $Bi_2MoO_6$ catalysts prepared using EGME as a solvent showed the highest photocatalytic activity. In addition, the $Bi_2MoO_6$ catalysts prepared at $180^{\circ}C$ showed the highest photocatalytic activity. The PL peaks appeared at about 560 nm at all catalysts and the excitonic PL signal was proportional to the photocatalytic activity for the decomposition of Rhodamin B. This suggests that the stronger the PL intensity, the larger the amount of oxygen vacancies and defects, and the higher the photocatalytic activity.