• Composites Research
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• v.34 no.3
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• pp.148-154
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• 2021

Carbon/epoxy composite bipolar plate (BP) is a BP that is likely to replace existing graphite bipolar plate of vanadium redox flow cell (VRFB) due to its high mechanical properties and productivity. Multi-functional carbon/epoxy composite BP requires graphite coating or additional surface treatment to reduce interfacial contact resistance (ICR). However, the expanded graphite coating has the disadvantage of having low durability under VRFB operating conditions, and the surface treatments incur additional costs. In this work, an excessive resin absorption method is developed, which uniformly removes the resin rich area on the surface of the BP to expose carbon fibers by applying polyester fabric. This method not only reduces ICR by exposing carbon fibers to BP surfaces, but also forms a unique ditch pattern that can effectively hold carbon felt electrodes in place. The acidic environmental durability, mechanical properties, and gas permeability of the developed carbon/epoxy composite BP are experimentally verified.

• Journal of the Korean Ceramic Society
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• v.38 no.6
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• pp.509-514
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• 2001

흑연과 수지의 결합력 증진을 위해 산세척을 통해 표면에 활성을 도입하였다. 흑연표면의 FTIR 관찰결과, 초산의 농도에 비례하여 탄소표면에 -O-C=O와 -OH 흡수 띠의 강도가 증가되었다. 시편의 마찰계수는 높은 밀도와 경도 및 강도를 나타내는 조성의 시편에서 낮고 안정된 마찰계수를 보였다. 거리에 따른 마찰계수를 측정한 결과, 흑연블럭은 마찰초기에 낮은 마찰계수 값을 가지나 거리가 증가함에 따라 안정되지 못한 마모가동을 나타내었다. 반면 수지결합질 탄소재는 마찰초기에는 높은 마찰계수를 나타내었지만 마모가 진행되면서 윤활층 형성으로 인해 안정된 마찰거동을 나타내었다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.05a
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• pp.77-81
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• 2002

콘크리트에 탄소를 혼합하여 제작하면 탄소자체의 흡수성질이 있어 배합콘크리트에 밀실하게 배합되기가 쉽지 않으나 일단 밀실하게 제작되면 압축강도가 크게 개선되는 것으로 전기$\cdot$전도에 큰 성능개선을 할 수 있는 것으로 보여진다. 콘크리트에 전선을 매입하여 그 특성을 개선하는 등 해외 및 국내 연구들이 진행되고 있다. 본 연구에서는 기구 매입 없이 초기 배합에서 곧바로 전기적 특성을 이러한 방향으로 개선하는 방법을 찾는 기초연구를 하는데 있다.(중략)

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.24-25
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• 2009

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2023.04a
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• pp.114-115
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• 2023

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.649-656
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• 2015

The objective of this study was to analyze the optimal thinning regimes for timber or carbon managements in Cryptomeria japonica stands of Hannam Experimental Forest, Korea Forest Research Institute. In solving the problem, PATH algorithm, developed by Paderes and Brodie, was used as the decision-making tool and the individual-tree/distance-free stand growth simulator for the species, developed by Kwon et al., was used to predict the stand growth associated with density control by thinning regimes and mortality. The results of this study indicate that the timber management for maximum net present value (NPV) needs less number of but higher intensity thinnings than the carbon management for maximum carbon absorption does. In case of carbon management, the amount of carbon absorption is bigger than that of timber management by about 6% but NPV is reduced by about 3.2%. On the other hand, intensive forest managements with thinning regimes promotes net income and carbon absorption by about 60% compared with those of the do-nothing option.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.373-374
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• 2000

최근 대기중 이산화탄소함량의 증가는 지구온난화의 관점에서 상당한 주목을 받고 있으며 이산화탄소의 흡수저장 능력을 가진 산림내 탄소저장능력에 대한 관심을 증가하고있다(Vitousek, 1991; Alban 과 Perala, 1992). 주로 유기물로 존재하는 산림생태계내 유기탄소는 지구탄소순환에 크게 기여할 뿐만 아니라 토양 이화학적 특성과 밀접한 관련을 가지는 것으로 알려져 있다(Alban 과 Pelara 1992). 본 연구는 경기도 광릉에 위치한 밀도와 지위가 다른 31년생의 성숙한 리기다소나무임분을 대상으로 탄소저장량과 년 탄소증가량이 어느 정도 되는지를 알아보기 위해서 실시하였다.(중략)

• Journal of Environmental Impact Assessment
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• v.27 no.2
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• pp.124-138
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• 2018

This research was conducted to examine the availability of spatial data for assessing absorption rates of $CO_2$ in the forest of Ansan-si and evaluate the validity of methods that analyze $CO_2$ absorption. To statistically assess the $CO_2$ absorption rates per year, the 1:5,000 Digital Forest-Map (Lim5000) and Standard Carbon Removal of Major Forest Species (SCRMF) methods were employed. Furthermore, Land Cover Map (LCM) was also used to verify $CO_2$ absorption rate availability per year. Great variations in $CO_2$ absorption rates occurred before and after the year 2010. This was due to improvement in precision and accuracy of the Forest Basic Statistics (FBS) in 2010, which resulted in rapid increase in growing stock. Thus, calibration of data prior to 2010 is necessary, based on recent FBS standards. Previous studies that employed Lim5000 and FBS (2015, 2010) did not take into account the $CO_2$ absorption rates of different tree species, and the combination of SCRMF and Lim5000 resulted in $CO_2$ absorption of 42,369 ton. In contrast to the combination of SCRMF and Lim5000, LCM and SCRMF resulted in $CO_2$ absorption of 40,696 ton. Homoscedasticity tests for Lim5000 and LCM resulted in p-value <0.01, with a difference in $CO_2$ absorption of 1,673 ton. Given that $CO_2$ absorption in forests is an important factor that reduces greenhouse gas emissions, the findings of this study should provide fundamental information for supporting a wide range of decision-making processes for land use and management.

• Journal of Korea Foresty Energy
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• v.23 no.2
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• pp.1-8
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• 2004

This study looked into the change of tree growth of seven forest growth monitoring plots which were set up at the Undulyeong Hongchungun Kangwondo, and was accomplished to offer the basic data for the forest administration calculating carbon storage and removal in the Undulyeong area. Annual height and DBH growth were slowly progressed in the Pinus koraiensis and Larix kaempferi stand which was young stand, but the growth rate of the other stands was lower than those young stand. The diameter class of the mixed forest and Qurcus mongilica stand was predicted to be similar to the now and Pinus koraiensis and Larix kaempferi stand was predicted to move now diameter class to the high diameter class because thickening growth speed of the those stands were rapid. Now the end of 2003, total carbon storage of the Undulyeong model forest increased 149,000TC$(2.7\%)$ compared with the previous year. Seeing by forest types, occupied broad-leaved forest$(50\%)$, mixed forest$(34\%)$ and coniferous forest. During in 2003, total carbon which was removed and stored according to growth of the forest was 156,813TC and net carbon removal(148,664TC) increased into 2,613TC$(1.8\%)$ compared with the previous year. Seeing by forest types, occupied coniferous forest$(3.3\%)$, mixed forest$(3.1\%)$, broad-leaved forest$(2.8\%)$. Resultingly, the Undulyeong model forest is acting to net removal resource when see as green-gas side and net carbon removal are showing the tendency to increase recently little by little.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.1
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• pp.44-53
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• 2006

In this study, the non-destructive computed tomography was adopted to observe the density profile of the needle-punched Carbon/Carbon(C/C) composites nozzle throat. The density profile of C/C was evaluated within ${\pm}0.01g/cm^3$ with 98.74% confidence when the correction of the image and high signal-to-noise ratio were achieved by the optimization of the beam hardening, the electrical noise and the scattered X-ray. The density variation of C/C with the computed tomography was in good agreement with the results obtained by the water immersion method and the observation with scanning electron microscope.