• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.654-658
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• 2014

풍력발전은 재생에너지로써 유망한 대체 에너지원으로 각광받고 있으며, 국내에서는 이미 영덕, 영양 등의 풍력단지가 가동 중에 있다. 그러나 장기간 사용되어온 터빈이 반 이상이며, 그 중에서도 바람의 영향을 많이 받는 블레이드는 끝단 Tip이 벌어지는 파손이 발생하곤 한다. Blade Field의 유지보수를 통해 수명연장이 가능하나, 형상변화로 공력특성에 영향을 미치게 된다. 본 연구에서는 MEXICO 터빈용 블레이드의 Tip부분에 대해서 EDISON을 활용하여, 수리로 인해 변경된 Blade의 공력특성 변화를 분석하였다. 형상변경은 상용 프로그램 Pontwise로 작업했으며, 익형 주위의 유동을 2D비압축성 유동으로 가정하고 EDISON CFD의 2D_Incomp-2.1_P solver를 수치해석을 수행하였다.

• The Korean Journal of Zoology
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• v.34 no.1
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• pp.103-109
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• 1991

한국 특산종 Cobitis longicorpus (왕종개)의 주요 분류형질인 골절반의 지리적 변이를 조사하기 위하여 남한의 12개집단 205개체를 이용, 골질반의 type분석과 계수학분석을 실시하였다. Type분석 결과, 동해유입하천집단(영덕의 송천, 축산천, 경주 형산강, 울주 회야강)의 골질반은 등근 삼각형, 삼각형, 인각형으로 남해 유입하천 및 도서집단의 타원형, 반타원형, 부채꼴과 구별되었다. 골질반의 계수화분석 결과에서도 동해유입하천의 골질반 폭은 비교적 좁아 남해유입하천 및 도서지방과의 평균 CD값이 1.64로 새종 수준 이상의 차이를 보였다. 아울러 조사, 비교된 제 1 체측반문도 동해유입하천에서는 C. longicorpus의 특징이 전혀 나타나지 않아, 원기재질단인 섬진강집단을 포함한 남해유입하천 및 도서집단과 구별된 새종수준의 종분화가 이루어진 것으로 사료되었다.

• Korean Journal of Environment and Ecology
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• v.10 no.1
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• pp.140-150
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• 1996

The freshwater fish fauna of the Chuwangsan National Park as censused during June 1994 to December 1994 at 11 sampling sites to establish baseline data included 7 Korean endemic species and subspecies (Squalidus gracilis majimae, Squalidus multimaculatus, Cobitis longicorpus, Niwaella multifacisciata, Silurus microdorsalis, Liobagrus mediadiposalis and Odontobutks platycephala) belonging to 17 species in 6 families were collected in this region. Carassius auratus, Moroco oxycephalus, Zacco platypus, Wacco temmincdii, Misgurnus anguillicaudatus, Liobagrus mediadiposalis and Odontobutis platycephala were distributed at all of the regions on this sensus. Dominant species of thes region sere Moroco ozycephalus, Zacco temminckii and Odontobutis platyxephala.

• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.173-192
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• 2012

Previous age data were reviewed for 98 sites of Phanerozoic granitoids in the southern part of the Korean Peninsula. Subduction-related granitic magmatism has occurred in southeastern Korea since Early Permian. In the middle part of the Yeongnam massif, arc-related tonalites, trondhjemites, granodiorites, and monzonites were emplaced during Early Triassic. After Middle Triassic continental collision in central Korean Peninsula, post-collisional shoshonitic and high-K series and A-type granitoids were emplaced in the southwestern Gyeonggi massif and central Okcheon belt during Late Triassic. Early Jurassic calc-alkaline granitoids are mostly distributed in the middle part of the Yeongnam massif and Mt. Seorak area, northeastern Gyeonggi massif. On the other hand, Middle Jurassic calc-alkaline granitoids pervasively occur in the Okcheon belt and central Gyeonggi massif. This selective distribution could be attributed to the change in the position of trench, subduction angle, or the direction of subduction. Most Cretaceous and Paleogene granitoids are distributed in the Gyeongsang basin, with the latter emplaced exclusively along the eastern coastline. Outside the Gyeongsang basin, Cretaceous granitoids emplaced in relatively shallow depth occur in the Gyeonggi massif and central Okcheon belt.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.2
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• pp.114-124
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• 2014

For classifying fire damaged areas and analyzing burn severity of two large-fire areas damaged over 100 ha in 2011, three methods were employed utilized supervised classification, unsupervised classification and Normalized Difference Vegetation Index (NDVI). In this paper, the post-fire imageries of SPOT were used to compute the Maximum Likelihood (MLC), Minimum Distance (MIN), ISODATA, K-means, NDVI and to evaluate large-scale patterns of burn severity from 1 m to 5 m spatial resolutions. The result of the accuracy verification on burn severity from satellite images showed that average overall accuracy was 88.38 % and the Kappa coefficient was 0.8147. To compare the accuracy between burn severity and field survey at Uljin and Youngduk, two large fire sites were selected as study areas, and forty-four sampling plots were assigned in each study area for field survey. The burn severities of the study areas were estimated by analyzing burn severity (BS) classes from SPOT images taken one month after the occurrence of the fire. The applicability of composite burn index (CBI) was validated with a correlation analysis between field survey data and burn severity classified by SPOT5, and by their confusion matrix. The result showed that correlation between field survey data and BS by SPOT5 were closely correlated in both Uljin (r = -0.544 and p<0.01) and Youngduk (r = -0.616 and p<0.01). Thus, this result supported that the proposed burn severity analysis is an adequate method to measure burn severity of large fire areas in Korea.

• The Korean Journal of Petroleum Geology
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• v.1 no.1 s.1
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• pp.15-27
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• 1993

Seismic reflection profiles from the eastern continental margin of Korea delineate three major Neogene sedimentary basins perched on the shelf and slope regions: Pohang-Youngduk, Mukho and Hupo basins. The stratigraphic and structural analyses demonstrate that the formation and filling of these basins were intimately controlled by two phases of regional tectonism: transtensional and subsequent contractional deformations. In the Oligocene to Early Miocene, back-arc opening of the East Sea induced extensional shear deformation with dextral strike-slip movement along right-stepping Hupo and Yangsan faults. During the transtensional deformation, the Pohang-Youngduk Basin was formed by pull-apart opening between two strike-slip faults; in the northern part, block faulting caused to form the Mukho Basin between basement highs. As a result of the back-arc closure, the stress field was inverted into compression at the end of the Middle Miocene. Under the compressive regime, two episodes (Late Miocene and Early Pliocene) of regional deformation led to the destruction and partial uplift of the basin-filling sequences. In particular, during the second episode of compressive deformation, the Hupo fault was reactivated with an oblique-slip sense, which resulted in an opening of the Hupo Basin as a half-graben on the downthrown fault block.

• The Journal of the Petrological Society of Korea
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• v.23 no.3
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• pp.279-292
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• 2014

Nd isotopic compositions analyzed from the Phanerozoic granitoids of Korea are integrated and discussed. Variations in Nd isotopic compositions can be explained either by temporal trend or by regional differences. Among the three active periods, first two periods during the Permian-Triassic and Jurassic seem to show variations from rather high ${\varepsilon}_{Nd}(t)$ values at the beginning to lower ${\varepsilon}_{Nd}(t)$ values during the later stages. Such trends probably reflect melting of the subducting oceanic crust and producing magma with higher proportion of depleted mantle derived materials during the early stage of subduction process, and subsequent magmas with greater proportion of old continental crust with progress of subduction. However, the Cretaceous-Paleogene period of active magmatism displays higher ${\varepsilon}_{Nd}(t)$ values during the advanced stage of the igneous activities, which is opposite to the previous active periods. The other explanation is that such differences in ${\varepsilon}_{Nd}(t)$ reflect regional differences, based on the observations that such high-${\varepsilon}_{Nd}(t)$ granitoids distribute in the northeastern Gyeongbuk Province and Gyeongsang Basin. If this is the case, the regions with highr ${\varepsilon}_{Nd}(t)$ values may have distinct crustal evolution histories, e.g. younger average age. The choice between the two hypothesis could be made through further studies.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.142-154
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• 2023

As the importance of the environment has been recognized worldwide, the need to calculate and reduce carbon emissions has been drawing an increasing attention throughout various industrial sections. Thereby the discipline of LCA (Life Cycle Assessment) involving raw material preparation, production processes, transportation and installation has been established. There is a clear research gap between the need and the practice for Korean Case of renewable energy industry, particularly wind power. To bridge the gap, this study conducted LCA research on wind power generation in the Korean area of Yeongdeok, an example of a domestic onshor wind power complex using SimaPro, which is the most widely used LCA system. As a result of the study, the energy recovery period (EPT) of one wind turbine is about 10 months, and the GHG emitted to generate power of 1 kwh is 15 g CO₂/kWh, which is competitive compared to other energy sources. In the environmental impact assessment by component, the results showed that the tower of wind turbines had the greatest impact on various environmental impact sectors. The experience gained in this study can be further used in strengthening the introduction of renewable energy and reducing the carbon emission in line with reducing climate change.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.401-401
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• 2020

최근 전 세계적으로 기후변화로 인한 자연재해가 빈번하게 발생하고 있으며, 우리나라 역시 해마다 가뭄과 홍수 등의 피해가 큰 실정이다. 특히 가뭄으로 인한 피해는 농업분야와 직결되어 있으며, 미래식량과 물안보에 영향을 미친다. 최근에는 국내 물관리일원화 정책에 따른 통합물관리 시행으로 수요관리에 의한 물이용 효율성이 물관리 기본원칙으로 포함되어 있어, 농업용수 분야의 물절약 필요성과 중요성은 더욱 증대되고 있는 실정이다. 농업농촌부문 가뭄대응 종합대책의 일환으로 2016년부터 농업용수 이용자 측면에서 물절약 실천을 유도하기 위한 물절약 교육 모델의 개발과 농업인 대상 시범교육이 실시되고 있으나 일부 지역에만 단발성 사업으로 제한적으로 추진되고 있는 실정이다. 따라서 물절약 교육 및 홍보사업을 보다 체계적이고 광법위하게 적용하여 농업 현장에서의 가시적인 물절약 성과를 도출하기 위한 노력이 요구된다. 이에 대한 일환으로 본 연구에서는 물절약 교육 콘텐트 개발 및 현장 교육에 반영하기 위하여 농업인 대상 물절약 의식과 행동실천 여부에 대해 조사를 실시해 보았다. 포항 및 영덕지역의 한국농어촌공사 관할지구 내 농업용수 이용자 중 수리시설감시원(이하 '수감원') 100여명을 대상으로 설문조사로 파악해 보았다. 설문에 참여한 수감원들은 대부분 65세 이상의 고령으로 농업에 오랜 기간 종사한 경험의 소유자로서 소규모 농업경영이 주를 이루었다. 대부분 농사기간동안 물부족 경험이 있었으며, 모내기 및 벼생육기 강우조건에 따라 물부족을 경험한 것으로 파악되었다. 이로 인해 설문 참여자들의 물절약 필요성에 대해서는 높은 공감대를 나타내었으며, 특히 농업인 대상 물절약 교육의 필요성에 대해서 매우 높은 공감대를 나타내었다. 농업인의 물과다 사용 및 물꼬관리 부실 등 필지단위 물관리 부실에 대해서도 상당히 인정하는 편이었으며, 이러한 농업인의 관행적인 물관리 행태에 대해서 변화를 유도할 수 있는 수리계조직 부활을 통한 농업인 물관리 직접 참여 등의 대안이 필요하다는 의견에 대해서도 긍정적이었다. 또한 농업인 용수이용에 대한 비용 부담에 대해서도 다소 긍정적인 의견도 제시되었다. 본 연구 결과로 농업인의 적극적인 물관리 및 물절약 참여를 이끌어 낼 수 있는 실현가능한 관련 제도 마련의 필요성과 체계적이고 지속적인 물절약 교육 및 홍보 정책 추진의 필요성이 제기된다.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.75-82
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• 2023

The samples used in this study were collected on two occasions (April 21 and May 16, 2021) from Liobagrus mediadiposalis and spawned egg masses located under rocks in Daeseocheon, Yeongdeok-gun, Gyeongsangbuk-do. Fertilized eggs ranged in size from 3.30~3.92 (average 3.57±0.19) mm (n=30), and it took 152~155 hours to hatch at water temperatures of between 17.0 and 20.0℃. Newly hatched larvae immediately post-hatching had a total length of 6.43~6.67 (6.55±0.07) mm (n=30), and were characterized by the retention of a yolk sac and an incompletely open mouth and anus, consistent with the yolk. On the 9 days post-hatching, the postflexion larvae had grown to length of between 11.0~13.8 (12.3±0.70) mm (n=30), and the caudal bone at the tip of the tail was bent upwards at an angle of 45°, thereby indicating the transition to the late larval growth stage. On the 16 days post-hatching, the total length of juvenile had increased to between 15.8~18.2 (16.8±0.77) mm (n=30), and the number of fins reached a fixed number of 8 dorsal, 17 anal, and 8 pelvic fins. On the basis of the findings of this study, we were able to confirm differences in the size of hatching larvae and fin mottle patterns in the early life history of related species.