• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.5
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• pp.437-441
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• 2014

This paper presents a novel microplatform for high power generation based on reverse electrodialysis. The ideal cation-selective membrane for power generation was realized using geometrically controlled in situ self-assembled nanoparticles. Our proposed membranes can be constructed through a simple and cost-effective process that uses microdroplet control with nanoparticles in a microchannel. Another advantage of our system is that the maximum power and energy conversion efficiency can be improved by changing the geometry of the microchannel and proper selection of the nanoparticle size and material. This proposed platform can be used to supply power sources to other microdevices and contribute to a fundamental understanding of ion transport behavior and the power generation mechanism.

• Journal of Electrochemical Science and Technology
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• v.10 no.2
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• pp.185-195
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• 2019

The large surface area and the high electrical conductivity of graphene (GP) allow it to act as an "electron wire" between the redox center of biomolecules and an electrode surface. The faster electron transfer kinetics and excellent catalytic activity of GP facilitate the accurate and selective electrochemical detection of biomolecules. This mini-review provides an overview of the recent developments and progress of GP, functionalized or doped GP, and GP-composites based sensors for the selective and interference-free detection of dopamine (DA). The electrochemical principles and future perspective and challenges of DA sensors were also discussed based on GP.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.97-97
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• 2013

The exterior structures of natural organisms have continuously evolved by controlling wettability, such as the Namib Desert beetle, whose back has hydrophilic/hydrophobic contrast for water harvesting by mist condensation in dry desert environments, and some plant leaves that have hierarchical micro/nanostructures to collect or repel liquid water. In this work, we have provided a method for wettability contrast on metals by both nano-flake or needle patterns and tuning of the surface energy. Metals including steel alloys and aluminum were provided with hierarchical micro/nanostructures of metaloxides induced by fluorination and a subsequent catalytic reaction of fluorine ions on metal surfaces in water with various ranges from room to boiling temperature of water. Then, a hydrophobic material was deposited on the structured surfaces, rendering superhydrophobicity. Plasma oxidization induces the formation of superhydrophilic surfaces on selective regions surrounded by superhydrophobic surfaces. We show that wettability contrast surfaces align liquid water within patterned hydrophilic regions during the condensation process. Furthermore, this method could have a greater potential to align other liquids or living cells.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.11a
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• pp.351-352
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• 2013

에너지 하베스팅 무선 센서 네트워크 환경에서 센서는 에너지 하베스팅 모듈을 통하여 배터리를 충전하고 충전된 배터리를 이용하여 동작을 한다. 센서는 컨트롤러에게 고정적인 주기로 데이터와 Reclaim 메시지를 전송하고 컨트롤러는 그에 대한 응답으로 ACK 메시지를 전송한다. 본 논문에서는 센서가 컨트롤러에게 데이터와 Reclaim 메시지를 전송하는데 있어 고정적인 주기를 센서 주변의 온도 정보를 이용하여 데이터의 전송주기 및 Reclaim 메시지를 동적으로 제어하여 ACK 메시지를 선택적으로 수신하도록 하였다. 제안하는 선택적 ACK 프로토콜은 기존의 ACK 프로토콜을 저 전력화하는 방법으로써 센서의 한정된 배터리 전력을 보다 효율적으로 사용하여 에너지 하베스팅 무선 센서 네트워크의 Life Time을 연장하였다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.358-364
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• 2021

This study was conducted to select a desiccant and determine its concentration for safe usage to improve the harvesting efficiency of soybeans. Soybeans were treated with a desiccant (non-selective herbicide) before and after the maturation stage. The drying effect of the desiccant was higher at earlier treatment times than at the maturation stage, but the difference was not statistically significant. The higher efficacy might be related to the drying process of the leaves and stems, with most of the leaves and stems having already been dried by the time of hand harvesting. Desiccant treatments had no adverse effects on soybean yield, weight of 100 grains, seed quality, or seed germination rate compared with the untreated control. Pesticide residue analysis showed minimum residue concentration to be lower than the tolerance level of pesticide residues. In conclusion, it was confirmed that the desiccant was effective in drying soybean, and that there was no damage to the quality of soybean seeds. In addition to the drying effect, the dessicant treatment also facilitates the removal of weeds that interfere with the mechanical harvest and improves harvesting efficiency through the drying of the growth imbalanced individual. The desiccant treatment is expected to shorten the mechanical harvesting time by 1-2 weeks. It is thought that the selection of the proper cultivation period for other crops after soybean cultivation will be more advantageous.

• The Plant Pathology Journal
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• v.30 no.1
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• pp.58-67
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• 2014

The multifunctional triple gene block protein 1 (TGB1) of the Potexvirus Alternanthera mosaic virus (AltMV) has been reported to have silencing suppressor, cell-to-cell movement, and helicase functions. Yeast two hybrid screening using an Arabidopsis thaliana cDNA library with TGB1 as bait, and co-purification with TGB1 inclusion bodies identified several host proteins which interact with AltMV TGB1. Host protein interactions with TGB1 were confirmed by biomolecular fluorescence complementation, which showed positive TGB1 interaction with mitochondrial ATP synthase delta' chain subunit (ATP synthase delta'), light harvesting chlorophyll-protein complex I subunit A4 (LHCA4), chlorophyll a/b binding protein 1 (LHB1B2), chloroplast-localized IscA-like protein (ATCPISCA), and chloroplast ${\beta}$-ATPase. However, chloroplast ${\beta}$-ATPase interacts only with $TGB1_{L88}$, and not with weak silencing suppressor $TGB1_{L88}$. This selective interaction indicates that chloroplast ${\beta}$-ATPase is not required for AltMV movement and replication; however, TRV silencing of chloroplast ${\beta}$-ATPase in Nicotiana benthamiana induced severe tissue necrosis when plants were infected by AltMV $TGB1_{L88}$ but not AltMV $TGB1_{L88}$, suggesting that ${\beta}$-ATPase selectively responded to $TGB1_{L88}$ to induce defense responses.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.122-122
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• 2012

The exterior structures of natural organisms have continuously evolved by controlling wettability, such as the Namib Desert beetle, whose back has hydrophilic/hydrophobic contrast for water harvesting by mist condensation in dry desert environments, and some plant leaves that have hierarchical micro/nanostructures to collect or repel liquid water. In this work, we have provided a method for wettability contrast on metals by both nano-flake or needle patterns and tuning of the surface energy. Metals including steel alloys and aluminum were provided with hierarchical micro/nanostructures of metaloxides induced by fluorination and a subsequent catalytic reaction of fluorine ions on metal surfaces in water with various ranges from room to boiling temperature of water. Then, a hydrophobic material was deposited on the structured surfaces, rendering superhydrophobicity. Plasma oxidization induces the formation of superhydrophilic surfaces on selective regions surrounded by superhydrophobic surfaces. We show that wettability contrast surfaces align liquid water within patterned hydrophilic regions during the condensation process. Furthermore, this method could have a greater potential to align other liquids or living cells.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.231-237
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• 1998

This study was carried out to investigate the effects of curing methods on the concentration of ammonia during curing in burley tobacco leaves. The air-cured tobacco(KB108; Nicotiana tabacum L.) was grown at Chonju Tobacco Experiment Station in 1998 and the tenth leaves from the top on the stalk were harvested. Half of the harvested leaves were cured in normal air curing facility and the other leaves were cured in excessive curing facility. Stalk cut tobaccos were cured in horizontal curing facility. The leaves were sampled every five days from harvesting time to the end of curing(25 days). Ammonia concentration of leaves increased during curing period with a remarkable increase at yellowing stage. The concentration of ammonia was high in the primed cured leaves, while that of the excessive cured leaves was low. It is considered that the lower increase of ammonia in stalk cured leaves may be caused by the translocation from the leaves to the stalk during curing, while that of excessive cured leaves may be caused by the poor decomposition of protein and amino acid during curing by excessive moisture loss and high temperature condition.

• Journal of Climate Change Research
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• v.7 no.2
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• pp.137-142
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• 2016

To achieve large-scale carbon removals, a carbon offset project based on forest management was designed and its carbon stock change was estimated in this study. The project was designed for 874 hectares of forests in the Jin-An Leading Forest Management Zone. For estimating the carbon stock change of the project, the Korean Forest Carbon Standard and VCS (Verified Carbon Standard) methodologies were applied. Three types of management options were considered in the project : extension of rotation age, conversion to productive forests, and conversion to selective harvesting. The estimated carbon removals from the project designed in this study were $259,936tCO_2$ ($8,664tCO_2$ annually), which is 98% of estimated carbon removals from the entire 69 projects currently registered to the Forest Carbon Offset Registry in Korea. The results of this study showed that a large-scale carbon offset project based on forest management could have a huge potential to produce carbon offset credits.

• Journal of the Korean Solar Energy Society
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• v.39 no.4
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• pp.25-39
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• 2019

Luminescent solar concentrator (LSC), consisting of luminophore included glass or substrate with edge-mounted photovoltaic cell, is semi-transparent, energy harvesting devices. The luminophore absorbs incident solar light and re-emit photons, while the waveguide plate allows re-emitted photons to reach edge or bottom mounted photovoltaic cells with reduced losses. If the area of LSC is much larger than that of photovoltaic cell, this system can effectively concentrate solar light. In order to improve the performance of LSC, new materials and optical structures have been suggested by many research groups. For decreasing re-abosprion losses, it is essential to minimize the overlap between absorption and photoluminescence solar spectrum of luminophoroe. Moreover, the combination of selective top reflector and reflective optical cavity structure significantly boosts the waveguide efficiency in the LSC. As a result of many efforts, commercially available LSCs have been demonstrated and verified in the outdoor. Also, it is expected to generate electricity in buildings by replacing conventional glass to LSCs.