• 한국자원식물학회지
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• 제23권3호
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• pp.242-247
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• 2010

This study was carried out to elucidate the effect of mulching materials on the growth of Chinese chive (Allium tuberusum Rottler) and weed control. Chinese chive was grown under five mulching materials, pine leaf, oak leaf, rice straw, rice hull and sawdust, at the Experimental Farm of Chungbuk National University from June 20, 2009 to September 30, 2009. Amaranthus mangostunus, Digitaria sanguinalis, Portuclaca. oleracea, Echinochioa crus-galli var. frumetacea and Setaria viridis were dominant weeds. Both pine and oak leaves were significantly effective mulching materials in terms of weed control indices in both nursery and field. Soil moisture contents were 1.2~3.7% higher in mulching, especially in oak leaf mulching. Mulching with pine leaf significantly increased plant height, sheath length, leaf length, bulb-, root- and leaf-weights and yield of Chinese chive, but there were no significant differences among the other mulching materials although better than those in non-mulching.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 추계 학술발표회논문집
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• pp.326-333
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• 2003

Most long-span bridges such as a cable-stayed bridges have a number of long-period modes due to the flexibility, thus the design concept extending the natural period of structures using base isolation system may be difficult to use directly to these structures. But, the effectiveness of LRB for cable-stayed bridges is indicated in several papers. In this study, the guidelines of designing LRB for a seismically excited cable-stayed bridge using benchmark cable-stayed bridge are presented. The design properties of LRB are chosen that the design index(DI) is minimized or little changed for variation of properties. And the seismic performance of designed LRB is also investigated. The consequences show that the perforamnce of designed LRB is better than that of simply designed LRB for several history earthquakes. Moreover, the design properties of LRB are researched to several diffrent dominant frequency of earthquake. The results present that the plastic and elastic stiffness of LRB are affected by the dominant frequency of earthquake.

• 아시안잔디학회지
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• 제4권2호
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• pp.101-118
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• 1990

Effects of Zoysia japonica fired in winter on the arthropoda communities in its grassland and rice field was investigated . The results gave indicated that a significant difference between total 15,120 individuals of 4 classes, 11 orders, 47 families, 92 genera and 103 species in the control of Zoysia japonica grassland, and total 1, 404 individuals of 4 classes, 11 orders, 47 families, 53 genera 65 species in the Zoysia japonica grassland fired in winter. Index of similarity of Zoysia japonica grasslands between Kimpo and Yangsuri areas was 0.51. Dominant species of arthropoda communities in Zysia japonica grasstands in Kimpo and Yangsuri areas were Hypogastnua sp. and Proisotorn sp., respectively. The spiders were 9 families and 27 species at Kimpo, and t2 families. and 44 species at Yangsuri, and their dominant species was Gnathonariurn dentaturn at two areas. Laodelphex striatelus in the Zoysia japonica grassland fired in winter was sampled constantly morning, noon and night, hut Gnatlzonariun dentatum was sampled more frequently in the morning than at night. Damage of the spiders in the Zoysia japonica granssland fired in winter was more severe than that of Laodelphcx striatelus .

• 한국수산과학회지
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• 제46권6호
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• pp.843-850
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• 2013

The feeding habits of Lycodes tanakae Eelpout were studied with 722 specimens collected from March 2011 to December 2012 in the coastal waters of the middle East Sea. The main prey of L. tanakae were fish, molluscs and arthropods. Nevertheless annelida, echinodermata and others were found in small amounts in the stomach contents. The L. tanakae stomach was empty of contents in 50.9% of specimens. While smaller size specimens of L. tanakae (less than 40 cm) fed mainly on euphausiids and amphipods, the larger specimens (more than 40 cm) fed on the fish Allolepis hollandi and Icelus cataphractus, and the molluscs Berryteuthis magister and Watasenia scintillans. The main prey items of L. tanakae varied seasonally. The fish Lycodes nakamurai was the dominat prey from November to January during its spawning season. Euphausiids and amphipods of the arthropods were the dominant prey from February to April. The molluscs Berryteuthis magister and Watasenia scintillans were the dominant prey from May to September. The diversity index (H') of diets showed variations by length class and month; the highest values were 2.61 in the length class of 51-55 cm, and the monthly highest were 2.68 in September with 23 species and 2.65 in November with 18 species. The highest dominance index (D') of diets was 0.57 in the length class of 31-35 cm, and the monthly highest was 0.71 in February. Cluster analysis divided prey groups into four groups by length class and three groups by monthly prey items. The gonad index gradually increased during the process of maturation while, contrary, stomach content index decreased during this period.

• 환경생물
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• 제26권3호
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• pp.233-239
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• 2008

본 연구는 한강하류역에서 2개 정점을 선정하여 2004년 2월부터 2005년 2월까지 갈수기에 격주 간격으로 인공기질을 이용하여 부착돌말류에 의한 수질평가를 수행하였다. 조사기간 중 출현한 부착돌말류는 총 60분류군으로 2목 3아목 8과 18속 51종 7변종 2품종으로 구성되어 있었다. 정점별 우점종은 정점 1에서 광적응성 종인 A. granulata (22.76$\sim$30.30%), M. varians (17.44$\sim$34.78%)와 호오염성 종인 N. palea (15.00$\sim$31.76%)등이 출현하였으며, 정점 2에서는 호오염성 종인 N. palea (19.86$\sim$58.20%)가 주요 우점종이 었다. DAIpo지수는 정점 1에서는 평균 40.6을, 정점 2에서는 평균 32.1로 각각 $\beta$-중부수성 수역이었으나, 정점 2에서 수질이 더 악화되어 있었다. 본 연구에서 출현한 우점종들이 한강하류역에서 수질 판정할 수 있는 주요 지표종이며, 이들의 상대빈도에 의한 DAIpo지수는 수질평가의 유용한 수단이 될 수 있었다.

• 환경영향평가
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• 제29권2호
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• pp.112-121
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• 2020

연안개발에 따른 유기물 오염은 유기물 오염지표종의 분포를 증가시키고, 증가된 유기물 오염지표종이 대상해역에 장기간 우점하여 저서생태계를 교란시킨다. 하지만 아직까지 우리나라 전 해역을 대상으로 조하대 저서생태계 유기물 오염정도를 확인한 연구가 미미한 실정이다. 이에 본 연구는 연안개발 환경영향평가 대상사업의 조하대 저서동물 조사결과를 분석하여 유기물 오염지표종의 분포를 확인하고, 우리나라 전 해역 조하대 유기물 오염정도를 간접적으로 확인하였다. 유기물 오염지표종별 분포 현황을 이미지 프로그램을 통해 지도로 작성하고, 전체 출현분포 현황을 통해 전 연안의 저서건강도지수(BHI, Benthic Health Index)를 도식화하였다. 유기물 오염정도는 사업구분 및 유기물 오염지표종별 분포가 다양하였으며, 유기물 오염지표종 중 Lumbrineris sp.가 전 해역에 가장 우점한 것으로 확인되었고, 전체 조하대 유기물 오염정도와 상관관계가 있는 것으로 확인되었다. 앞으로의 조하대 저서생태계 유기물 오염정도는 유기물 오염지표종 분포를 통해 확인하고, 향후 연안개발 계획 수립 시 참고자료로 활용할 수 있을 것으로 기대한다. 또한, 유기물 오염지표종 중 Lumbrineris sp.의 분포는 간접적으로 개발 대상지의 유기물 오염정도를 평가할 수 있는 지표로 사용 가능할 것으로 판단된다.

• 한국잡초학회지
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• 제1권1호
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• pp.78-83
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• 1981

한국(韓國)의 야생(野生)잔디가 재식(栽植)되에 있는 잔디밭을 대상(對象)으로 문제잡초구명(問題雜草究明) 및 잡초방제방법구명시험(雜草防除方法究明試驗)에서 얻어진 결과(結果)를 요약(要約)하면 다음과 같다. l. 본(本) 조사지역(調査地域)에서 발생(發生)된 잡초종류(雜草種類)는 40여종(餘種)이었고 발생빈도(發生頻度) 및 발생량(發生量) 면(面)에서 크로바, 바랭이, 방동산이, 망초, 꽃다지 등이 문제(問題)의 잡초(雜草)로 구명(究明)되었다. 2. 경산(慶山) 칸트리클럽 주변(周邊)의 조사지점(調査地點)에서는 크로바, 바랭이, 꽃다지, 방동산이, 망초 등이 공존(共存)하는 군락형(群落型)으로 Simpson's Index가 0.306이었고 경북대(慶北大) 캠펴스내(內)의 조사지점(調査地點)에서는 Simpson's Index가 0.776으로 주로 크로바가 우점(優占)하는 군락형(群落型)을 보였다. 전체(全體)의 건물중(乾物重) 증가양상(增加樣相)에는 두 지역간(地域間)에 시간적(時間的) 차이(差異)는 있으나 유사(類似)하였다. 3. 크로바와 광엽잡초(廣葉雜草)가 우점(優占)하는 지역(地域)에 MCPP 3.4kg (a.i.)/ha를 2회(回) 처리(處理)는 경미한 약해(藥害)가 있기는 하나 84.1%의 높은 방제효과(方劑효果)를 나타냈으며 MCPP 2.2~2.8kg (a. i.)/ha 처리(處理)도 약해(藥害)는 전혀 없으며 높은 방제효과(方劑效果)를 나타냈다. 4. 2,4-D 성분량(成分量)으로 2.0kg/ha 처리(處理)는 MCPP 3.4kg (a.i.)/ha 에 준(準)한 방제효과(方劑效果)를 나타내지는 못하였으나 높은 방제율(防除率)을 보였으며 약해(藥害)를 고려(考慮)할 때 2,4-D 1.0kg (a.i.)/ha 정도면 광엽잡초방제(廣棄雜草防除)에 유효(有效)할 것이다.

• 환경영향평가
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• 제14권4호
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• pp.237-245
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• 2005

We investigated the water environmental assessment by the species biotic index (SBI) of freshwater fish at the Namdaecheon in Gangneung city, Gangweon-do during June and July in 2004 and June in 2005. In fish fauna, 29 species and 10 families were collected. Dominant species was Zacco platypus (relative abundance 15.33%) and subdominant species was Rhynchocypris steindachneri (13.13%). Species biotic index (SBI) in station 1, 2, 3, 4 was 1.70, 2.85, 1.00 and 3.39 respectively and water environmental grade by SBI was all very good. Station 5 was 4.13 in SBI and good grade. Station 6 was 4.47 and fairly good. Station 7 was 7.25 and poor. And station 8 was 8.10 and very poor grade. Results of water environmental grade by SBI and water quality grade were very similar in this stream.

• 전기학회논문지
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• 제56권6호
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• pp.1017-1022
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• 2007

In this paper, we try to analyze the likelihood of exercising the power of market dominance by certain generators in future power industry of Korea. Firstly, we estimated installed generation capacity and sales volume of electricity in Korea, based on 'The 3rd Long Term Power Plan' which was announced in December 2006. Secondly, we calculated HHI, an index showing the degree of concentration of an industry, and RSI, an index showing how adequate the supply of goods or services of an industry is, using Fast-Forward. Thirdly, assuming a major generator employs the strategy of withholding a part of its available capacity at a peak time, we simulated hypothetical movement of SMP over a certain period of time, which is compared with that obtained without assuming such strategy to generate Lerner Index. an index showing the degree of market power of a monopoly. Regulators, home and abroad, have not given much interest in analyzing the effect of market dominance that is likely to be exercised by certain players in the future. That said, this paper provides insight into developing methodologies of analyzing and mitigating such effect by proposing the above indices to gauge it. In addition, this paper also shows the potential impact of employing capacity withholding strategy on the financial account of a dominant generator.

• 환경영향평가
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• 제20권1호
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• pp.1-11
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• 2011

This study was carried out to suggest the baseline data necessary for vegetation restoration at riverine wetland within stream corridor. We used the prevalence index for wetland assessment by applying the method of weighted averages with index values based on five hydrophyte indicator status as defined by estimated probability occurred in wetland. We selected near nature and urbanized reach of Gap and Yanghwa streams as experimental site. Although two sites have some different disturbance and characteristics of watershed, they showed that similarity of vegetation community including three dominant species - Salix koreensis, Phragmites communis, Miscanthus sacchariflorus - was very high. But in case of Yanghwa stream, various kinds of emergent plants along wetted condition were distinctly occurred, resulted from difference of hydrological regime and substrate, etc. Degree of naturalness of vegetation at the sampled areas indicated that near nature area of Gap stream and all area of Yanghwa stream were fitted as riverine wetland, while urbanized area of Gap stream has changed into upland condition. In conclusion assessment system using prevalence index would be considered an effective method for evaluating of natural states of riverine wetland, but further integrated consideration of physical, hydrological, and biological factors of stream process, and also with considering the difference between those qualitative data of vegetation community.