• 한국환경과학회지
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• 제12권8호
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• pp.853-860
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• 2003

Plants sequester atmospheric CO$_2$, a major agent of climate change, during the growing periods and mitigate its rising accumulation in the atmosphere. Pinus densiflora and Quercus mongolica are the native tree species dominant in the temperate forests of Korea. This study quantified the annual CO$_2$ uptake by the two species at forest sites in Chuncheon in the middle of the country. The quantification was based on seasonal measurements of CO$_2$ exchange rates under natural conditions by an infrared gas analyzer over the growing season (1999). The monthly CO$_2$ uptake per unit leaf area ranged from 1.6-6.7 mg/d㎡/h for P. densiflora and from 3.7-8.9 mg/d㎡/h for Q. mongolica, with a maximum in mid-summer. An equation for each species was generated to estimate easily the annual CO$_2$ uptake by total leaf area per tree, which subtracted the CO$_2$ release (i.e. respiration) by leaves and woody organs from the gross CO$_2$ uptake (diurnal uptake and release by leaves). Annual CO$_2$ release by leaves and woody organs accounted for 58-73％ of the gross CO$_2$ uptake across tree specimens. Annual CO$_2$ uptake per tree increased with increasing dbh (stem diameter at breast height) for the study diameter range, and was greater for Q. mongolica than for P. densiflora in the same dbh sizes. This was mainly associated with a greater total leaf area in the former. For example, the annual CO$_2$ uptake by one tree with dbh of 25 cm was 35.6 kg/yr for P. densiflora and 47.9 kg/yr for Q. mongolica. The results from this study can be applied to evaluate an atmospheric CO$_2$ reduction of woody plants by forest type and age class.

• 한국의류학회지
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• 제8권3호
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• pp.31-42
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• 1984

This paper is a research on the origins and the developing process of $Dan-Ry\={o}ng$ centering on the change of its form. From the beginning of A. D era Central Asia had played the important role of a traffic route connecting China and its western adjacent world. Through this route $Dan-Ry\={o}ng$ was introduced into China (South-North Dynasty era). The form of $Dan-Ry\={o}ng$ in early period was Ban-Gum-Po (Open-collared costume that turn down the collar to the outside), and it could be worn close-collared or open-collared. From the fact that the people who wore $Dan-Ry\={o}ng$ in early period were mainly Iranian and that it was also worn by lower class like a waiting maid, it can be said that $Dan-Ry\={o}ng$ was not the costume of Han race. In early period the motif of the inside of collar was Persian style, and the people of central Asia was mostif Iranian. In short, $Dan-Ry\={o}ng$ was the costum of the people lived in the adjacent world west of China, particulary Iranians. The form of $Dan-Ry\={o}ng$ changed from Ho-Bok to Ban-Gum-Po owing to the differences in climate. In conclusion, $Dan-Ry\={o}ng$ originated in Ho-Bok ana was introduced into the world west of china by the movement of Horrse-riding Race. Then its form was changed owing to the factors like climate, natural and cultural features, and consepuently it was introduced into China by way of Centeral Asia. In China it was settled as $Dan-Ry\={o}ng$ through the ages of T'ang dynasty, Sung dynasty, Ming dynasty.

• 분석과학
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• 제36권5호
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• pp.236-249
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• 2023

Carbon dioxide (CO₂) capture and storage is a critical issue for mitigating climate change. Porous aromatic Schiff base complexes have emerged as a promising class of materials for CO₂ capture due to their high surface area, porosity, and stability. In this study, we investigate the potential of Schiff base complexes as an effective media for CO₂ storage. We review the synthesis and characterization of porous aromatic Schiff bases materials complexes and examine their CO₂ sorption properties. We find that Schiff base complexes exhibit high CO₂ adsorption capacity and selectivity, making them a promising candidate for use in carbon capture applications. Moreover, we investigate the effect of various parameters such as temperature, and pressure on the CO₂ adsorption properties of Schiff base complexes. The Schiff bases possessed tiny Brunauer-Emmett-Teller surface areas (4.7-19.4 m²/g), typical pore diameters of 12.8-29.43 nm, and pore volumes ranging from 0.02-0.073 cm³/g. Overall, our results suggest that synthesized complexes have great potential as an effective media for CO₂ storage, which could significantly reduce greenhouse gas emissions and contribute to mitigating climate change. The study provides valuable insights into the design of novel materials for CO₂ capture and storage, which is a critical area of research for achieving a sustainable future.

• 한국환경과학회지
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• 제22권2호
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• pp.139-149
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• 2013

Anthropogenic increases in greenhouse gas concentrations, primarily through radiative forcing from carbon dioxide, continue to challenge earth's climate. This study quantified $CO_2$ storage and uptake by dominant forest types and age classes in the middle region of Korea. In addition, the role of forest landscapes in reducing atmospheric $CO_2$ against $CO_2$ emissions based on energy consumption was evaluated. Mean $CO_2$ storage and uptake per unit area by woody plants for three forest types and four age classes were estimated applying regression equations derived to quantify $CO_2$ storage and uptake per tree; and computations per soil unit area were also performed. Total $CO_2$ storage and uptake by forest landscapes were estimated by extrapolating $CO_2$ storage and uptake per unit area. Results indicated mean $CO_2$ storage per unit area by woody plants and soils was higher in older age classes for the same forest types, and higher in broadleaved than coniferous forests for the same age classes, with the exception of age class II (11-20 years). $CO_2$ storage by broadleaved forests of age class V (41-50 years) averaged 662.0 t/ha (US$331.0 hundred/ha), highest for all forest types and age classes evaluated. Overall, an increased mean $CO_2$ uptake per unit area by woody plants was evident for older age classes for the same forest types. However, decreased $CO_2$ uptake by broadleaved forests at age class V was observed, compared to classes III and IV with an average of 27.9 t/ha/yr (US$14.0 hundred/ha/yr). Total $CO_2$ storage by woody plants and soils in the study area was equivalent to 3.4 times the annual $CO_2$ emissions, and woody plants annually offset the $CO_2$ emissions by 17.7%. The important roles of plants and soils were associated with 39.1% of total forest area in South Korea, and $CO_2$ emissions comprised 62.2% of the total population. Therefore, development of forest lands may change $CO_2$ sinks into sources. Forest landscape management strategies were explored to maintain or improve forest roles in reducing atmospheric $CO_2$ levels.

• 한국산림과학회지
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• 제110권1호
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• pp.64-71
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• 2021

최근의 기후변화는 산지토사재해의 발생을 가속시키고 있다. 산지토사재해 중 토석류는 전파길이가 길고 매우 빠른 거동 특성을 갖기 때문에 매우 위협적으로 인식된다. 본 연구는 설악산 국립공원내 토석류 발생지 263개소를 대상으로 발생 길이(m)에 미치는 영향인자를 구명하고, 수량화이론(I)을 사용하여 발생 길이에 대한 각 산림환경 인자의 기여도 분석을 하여 예방적인 측면에서 국립공원내 토석류 발생 가능성지역에 대한 예측기법을 개발하였다. 각 산림환경 인자의 Range를 추정한 결과, 종단사면(0.9676)이 가장 높게 나타나 설악산 국립공원의 토석류 발생 가능성에 큰 영향을 미치는 것으로 추정되었으며, 다음으로는 횡단사면(0.6876), 고도(0.2356), 사면경사(0.1590), 방위(0.1364) 순으로 나타났다. 설악산 국립공원 산악지 토석류 발생 발생가능성 판정표를 기준으로 5개의 산림환경 인자의 category별 점수를 계산한 추정치 범위는 0점에서 2.1864점 사이에 분포하고 있으며, 중앙값은 1.0932점으로 토석류 발생가능성을 예측을 작성한 결과 I등급은 1.6399 이상, II등급 1.0932~1.6398, III등급 0.5466~1.0931, IV등급 0.5465 이하로 나타나 1등급, 2등급에서 토석류 발생 비율이 86.3%로서 높은 적중률을 보였다.

• 한국지반환경공학회 논문집
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• 제14권3호
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• pp.35-40
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• 2013

일반적으로 동결대상지역에 설치되는 지반구조물은 동결피해에 대한 별도의 대책을 필요로 한다. 그러나 국내의 경우 터널, 옹벽 등과 같은 지반구조물에 대한 동결피해 조사 및 사례보고가 거의 이루어지지 않고 있어, 이를 저감시키기 위한 연구는 매우 미미한 실정이다. 이러한 이유로 국내의 구조물 관련 설계기준도 특별하게 이를 규정화하고 있지 않다. 본 연구에서는 터널, 비탈면, 옹벽의 동결피해에 대한 현장조사 및 1종, 2종 시설물에 대한 약 40여 년간의 지반구조물 유지관리 이력을 분석하여 구조물 설치지역의 기온에 따른 구조물의 유지관리 특성을 파악하였다. 그 결과 우리나라에서 동결깊이가 약 120cm 이상이고, 기온이 비교적 낮은 강원 산간지역 및 강원 북부, 경기 북부지역의 지반구조물은 기온이 비교적 따뜻한 타 지역과 달리 훨씬 더 오랫동안 보수보강을 필요로 하는 것으로 분석되었다. 이로부터 국내 동결피해 대상지역에 설치되는 구조물에 대한 설계기준 개정의 필요성을 제안하였다.

• 한국태양에너지학회 논문집
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• 제33권5호
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• pp.105-112
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• 2013

The new renewable energy became popular as a clean and sustainable alternative energy under the circumstances that the entire world is facing severe abnormal climate due to the use of fossil fuel, and among which, solar energy can be obtained anywhere and is not difficult to apply it into the existing buildings, which makes it possible to be widely distributed. However, as PV module is installed into a single plate system, it shows structural weaknesses which are vulnerable to wind load and give loss to design elements in external appearance. Accordingly, this study planned one-step parallel system to complement the problems occurring from a single plate system and used STAR-CCM+ V.8 made by CD-Adapco, a computational fluid dynamics(CFD) simulation tool to measure wind load stability and support based on the design standards for a single plate system and one-step parallel system. Building height was limited to less than 10m and wind speed was given when increasing from 35m/s to 50m/s by 5m/s on PV system installed into the flat roof. In this case, our analysis suggested that step-one parallel system was in class 7-9 according to Beaufort's wind power classification, which did not have an impact on the fixed PV system, and the single plate system is considered to cause risks in designing wind speed in central districts because it is more than wind power class 12.

• 자원ㆍ환경경제연구
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• 제27권4호
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• pp.695-723
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• 2018

최근 들어 기후변화로 인한 이상기후가 빈발해지고, 미세먼지 문제가 심각해짐에 따라 석탄화력발전에 대한 부정적인 인식이 커지고 있고, 경주 지진 이후 원자력 발전에 대한 사회적 수용력도 감소하고 있다. 본 연구는 선택실험법을 이용하여 중장기 전원별 일반 소비자들의 지불용의액을 도출함으로써 각 발전원에 대한 경제적 가치를 추정하고, 소비자들의 선호 이질성을 검토하였다. 적용한 방법론은 혼합로짓과 잠재계층모형이며, 혼합로짓 추정결과 특히 원자력에서 선호이질성이 크게 나타나는 것을 확인하였다. 잠재계층모형 추정결과 집단1은 신재생에너지를 선호하며, 집단2는 기존의 화석에너지를 선호하였다. 집단3은 사전편찬식 선호(제한적 합리성)을 보이는 집단으로 추정되었다. 사전편찬식 선호를 보이는 집단을 고려하지 않을 경우 지불용의액 추정의 신뢰성이 낮아지고, 속성의 유의성이 낮아지는 결과가 나타나는 것을 확인하였다. 또한 집단별로 에너지원에 대한 선호 이질성이 크게 나타나, 향후 전원구성에 있어 전력 소비자의 선호 이질성을 감안한 정책이 필요할 것이다.

• 신재생에너지
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• 제17권4호
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• pp.1-8
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• 2021

To determine the wind turbine class in the offshore of the Korean Peninsula, the reference wind speed for a 50-y return period at the hub height of a wind turbine was estimated using the reanalysis data sets. The most recent reanalysis data, ERA5, showed the highest correlation coefficient (R) of 0.82 with the wind speed measured by the Southwest offshore meteorological tower. However, most of the reanaysis data sets except CFSR underestimated the annual maximum wind speed. The gust factor of converting the 1 h-average into the 10 min-average wind speed was 1.03, which is the same as the WMO reference, using several meteorological towers and lidar measurements. Because the period, frequency, and path of typhoons invading the Korean Peninsula has been changing owing to the climate effect, significant differences occurred in the estimation of the extreme wind speed. Depending on the past data period and length, the extreme wind speed differed by more than 30% and the extreme wind speed decreased as the data period became longer. Finally, a reference wind speed map around the Korean Peninsula was drawn using the data of the last 10 years at the general hub-height of 100 m above the sea level.

• 의정연구
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• 제27권3호
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• pp.35-68
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• 2021

2021년 독일 총선에서 사민당이 신승해 제1당으로 복귀하고 녹색당이 최대 승자로 떠올랐다. 두 정당은 기후·환경, 팬데믹 대처와 보건, 노동·사회 정책에서 국민의 기대에 부응하는 정책을 제시함으로써 승기를 잡았다. 메르켈 효과는 선거에서 크게 작용하지 않았으며, 연정 구성 후 정부 정책으로 이어질 가능성이 크다. 투표 행태에서 계급 균열이 약해진 반면, 세대 균열이 상대적으로 커졌다. 노년층은 양대 정당에 더 많은 지지를 보냈고, 청년층은 녹색당과 자민당에 더 높은 지지율을 보였다. 세대 갈등이 계속된다면 녹색당과 자민당 등의 성장과 양대 정당의 지속적 약화 및 기타 새로운 정당의 등장으로 이어질 수 있다. 또한 구 동·서독 간 지역 갈등이 여전히 남아 있어 대안당과 좌파당의 향배에 영향을 미쳐 다른 균열들과 결합할 것이다. 2021년 총선은 정당 체제 재편을 예고하는 선거라고 할 수 있다.