• 한국환경복원기술학회지
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• 제27권2호
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• pp.67-90
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• 2024

The purpose of this study is to present the ecological data for conservation and management of three wetlands by surveying the vascular plants in Ganam reservoir, Ahnshim wetland and Jeomsae swamp. The whole taxa of vascular plants were 376 taxa including 90 families, 252 genera, 341 species, 7 subspecies, 24 varieties, 2 forms, 1 hybrid and 1 cultivar, and the planted species were 66 taxa including Ginkgo biloba and so on. The rare plants were 7 taxa including Euryale ferox(VU), Aristolochia contorta(LC), Koelreuteria paniculata(VU), Sagittaria trifolia(DD), Hydrocharis dubia(LC), Ottelia alismoides(LC) and Sparganium stoloniferum(VU). The Korean endemic plant was 1 taxon of Lespedeza maritima. In total, there were 21 taxa of floristic target species including 1 taxon of garde V, 2 taxa of grade IV, 6 taxa of grade III, 5 taxa of grade II and 7 taxa of grade I . The hydrophytes were 51 taxa including 36 taxa of emergent species, each 6 taxa of floating-leaved and submerged species and 3 taxa of free-floating species. The invasive alien plants were 79 taxa including 75 taxa of naturalized plants and 4 taxa of casual alien plant. The ecosystem disturbing species 6 taxa including Sicyos angulatus, Ambrosia artemisiifolia, Lactuca seriola, Symphyotrichum pilosum, Paspalum distichum and Humulus scandens.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.699-705
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• 2013

This paper presents vibration testing, control, and finite element analysis of a piping system, which is subjected to the changes in fluid levels. Nuclear power plants typically employ a cooling system that uses sea water. These systems are subjected to dynamic characteristic changes caused by sea-level variations, which introduces failures of cooling system components. Therefore in this study, analytical and experimental studies were performed to understand the effect of sea-level changes on the dynamic characteristics of piping systems. It was shown that, as the sea-level increases, pipe's natural frequencies decreases in relation to its mode shape. A 1/14 scale model was also built to compare the results obtained by the analytical study. A good agreement between experiment and analytical studies were observed. Finally, an on-line resonant frequency identification system was proposed and developed, which utilizes piezoelectric transducers as sensors and actuators, in order to avoid catastrophic failure of piping systems.

• ALGAE
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• 제19권3호
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• pp.191-199
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• 2004

Morphological and phonological characteristics of brown alga Spatoglossum crassum Tanaka new to Korea were described based on the field and the indoor cultured plants. The taxonomic characteristics of the plants were agreed to those from the type locality-submerged reproductive organs in cortex, anatomical features, and absence of phaeophycean hairs on the surface. But they have rudimentary midrib on lower portion of thallus. We can observe the young plants on November, adult ones in June, and senile ones in August. This species has an annual life-cycle in the field, starting with germ lings in early November. The differentiation of thallus is quite different from other species of genera in tribe Zonarieae, e.g. Zonaria and Homoeostrichus. Three different tissues, meristoderm, cortex and medulla are discerned. The outmost cortical one celled layer as a meristoderm produce cortex by unequal periclinal division. In the apical cell division, the primary inner cells are developed into 3-4 cell layered medulla of thallus. The distribution of this species extends from Korea to Shizuoka Peninsula (34°40'N) Japan, which is the type locality of this species.

• The Plant Pathology Journal
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• 제30권3호
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• pp.299-303
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• 2014

This study aims to isolate and identify the causal pathogen of tomato bacterial wilt in Egypt. In 2008, tomato plants showing typical symptoms of bacterial wilt disease with no foliar yellowing were observed in Minia, Assiut and Sohag governorates, Egypt. When cut stems of symptomatic plants were submerged in water, whitish ooze was evident and longitudinal sections showed a brown discoloration in the vascular tissues. Bacteria were isolated on triphenyl tetrazolium chloride medium and fifteen isolates shown typical morphological and cultural characteristics were confirmed as Ralstonia solanacearum biovar 2 race 1. Pathogenicity tests showed that all isolates proved to be pathogenic to tomato plants, varied from 52 to 97% wilting. This is the first report of R. solanacearum biovar 2 race 1 causing bacterial wilt in tomato crop in Egypt.

• 한국자원식물학회지
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• 제12권4호
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• pp.303-311
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• 1999

본 연구는 1997년 6월부터 1999년 7월까지 영산강집수역에서 수생식물과 특정식물 분포를 조사하였다. 조사된 수생식물은 정수식 19과 52종, 부유식물 5과 7종, 침수식물 7과 12종, 부엽식물 7과 15종으로 총 32과 86종이 나타났으며, 습지식물은 36과 135종으로 조사되었다. 감소추세종인 통발, 자라풀, 끈끈이주걱, 이삭귀개, 땅귀개와 멸종위기종인 순채와 가시연꽃이 확인되었다.

• 환경생물
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• 제23권2호
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• pp.120-128
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• 2005

2003년 3월부터 10월까지 영산강 수계 중 광주시 권역에서 선택한 총 14개 조사지역에서 수질의 이화학적 환경과 수생식물의 분포를 분석하였다. 전체 수생식물은 35과 68속 85종 9변종으로 총 94분류군이 확인되었다. 수계별로 수질의 이화학적 환경에 따라 오염지역과 비 오염지역을 구분하고 수생식물 분포양상을 확인하였다. 그 결과 가장 오염이 심한 것으로 여겨지는 광주천의 하류인 유덕동 일대에서 오염된 곳에 주로 분포하는 흰 꽃여뀌와 소리쟁이 등이 우점하였으며, 침수식물과 부엽 식물은 전혀 확인되지 않았다. 황룡강 일대와 영산강 상부지역 일대는 비교적 수질이 양호하여 비오염지역으로 판단되며, 이 지역에서 생육하는 달뿌리풀, 고마리, 물억새 등이 분포하였다. 광주시를 통과하는 동안 생활하수가 많이 유입되는 광주천 하류는 수생식물이 생육하기 힘든 수질환경인 것으로 판단되므로. 수질환경 개선을 위한 노력이 절실히 필요 할 것으로 판단된다.

• 한국환경복원기술학회지
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• 제20권2호
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• pp.61-77
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• 2017

The purpose of this study was to offer the basic data for conservation of wetland ecosystem by surveying and analysing the vascular plants distributed in Hwapocheon wetland, Gimhae, Gyeongnam, Korea. The numbers of vascular plants were summarized as 292 taxa including 72 families, 192 genera, 262 species, 1 subspecies, 26 varieties and 3 forms. There were 34 taxa of hydrophytes, 23 taxa of emergent plants, 4 taxa of floating-leaved plants, 5 taxa of free-floating plants and 5 taxa of submerged plants. The rare plants were 7 taxa including Aristolochia contorta, Penthorum chinense, Prunus yedoensis(planting), Ixeris tamagawaensis, Hydrocharis dubia, Iris ensata var. spontanea(planting), Acorus calamus and so forth. The Korean endemic plants were 2 taxa including Salix koriyanagi and Salix pseudolasiogyne. The specific plants by floristic region were 19 taxa including 2 taxa of grade V, 1 taxa of grade IV, 5 taxa of grade III, 2 taxa of grade II and 9 taxa of grade I. The naturalized plants were 62 taxa including Chenopodium album, Astragalus sinicus, Helianthus tuberosus, Panicum dichotomiflorum and so forth. The plants that were expected to spread nationwide were 14 taxa including Cerastium glomeratum, Bidens frondosa, Tagetes minuta, Festuca arundinacea and so forth. The invasive alien plants were 6 taxa including Rumex acetosella, Sicyos angulatus, Ambrosia artemisiifolia, Ambrosia trifida, Aster pilosus and Lactuca scariola.

• 상하수도학회지
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• 제20권4호
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• pp.519-526
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• 2006

In this study, the major operating factors in SND(simultaneous nitrification and denitrification) using bioreactor packed with submerged cilia media and granular sulfur such as variation of nitrification rate, organic matter removal efficiency and denitrification efficiency in different DO concentration were mainly evaluated. Synthetic wastewater and actual sewage were used as influent wastewater. Experiment with synthetic wastewater as influent wastewater was divided into three phases with the adjustment of DO concentration. As the results, nitrification efficiency and T-N removal efficiency in the Phase 3(DO 1.0~2.0 mg/L) were 99% and 52.3%, which is significantly greater than those in other two phases. Also, loading rate and denitrification efficiency of SCPGS(Submerged Cilia media Packed with Granular Sulfur) were calculated as $0.44kg\;NO_3^--N/m^3-day$ and 50%, respectively. On the other hand, nitrification rate was decreased from 99% to 64% according to the DO concentration with the variation from 3.0~3.5 mg/L(phase1) to 0.4~0.6mg/L(phase2). Although the nitrification rate was decreased in 64% according to the variation of the DO concentration, T-N removal rate was rapidly increased to 49% by increasing of the denitrification efficiency. Experiment with actual sewage as influent wastewater was carried out to evaluate efficiency of SCPGS in real operation condition of full-scale sewage water treatment plant. At the time, T-N removal rate in this experiment and full-scale wastewater treatment plants were given by 43% and 20%, respectively. The above results indicate that SCPGS can be used as an advanced treatment process for economical efficiency considered.

• 한국토양비료학회지
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• 제45권4호
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• pp.657-663
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• 2012

호소저수구역에서 수온이 침수식물체의 영양염류 용출에 미치는 영향을 평가하기 위해 $5^{\circ}C$ 및 $25^{\circ}C$ 조건의 칼럼에서 이삭사초와 물억새를 침수시킨 후 COD, T-N 및 T-P 함량을 조사하였다. 이삭사초의 침수 후 60일째 COD 용출량은 $5^{\circ}C$ 조건에서 $60.4mg\;L^{-1}$이었으며, $25^{\circ}C$ 조건에서 $78.0mg\;L^{-1}$이었다. 물억새의 침수 후 60일째 COD 용출량은 $5^{\circ}C$ 조건에서 $62.5mg\;L^{-1}$이었으며, $25^{\circ}C$ 조건에서 $70.5mg\;L^{-1}$이었다. 전반적으로 이삭사초에서는 $25^{\circ}C$ 조건이 $5^{\circ}C$ 조건에서 보다 COD 용출이 급증한 시기가 초기에 나타난 반면에 물억새에서는 COD 용출이 급증하는 시기가 온도별로 서로 유사한 경향으로 나타났다. 이삭사초의 침수 후 60일째 T-N 용출량은 $5^{\circ}C$ 조건에서 $45.8mg\;L^{-1}$이었으며, $25^{\circ}C$ 조건에서 $60.0mg\;L^{-1}$이었다. 물억새의 침수 후 60일째 T-N 용출량은 $5^{\circ}C$ 조건에서 $55.7mg\;L^{-1}$이었으며, $25^{\circ}C$ 조건에서 $61.0mg\;L^{-1}$이었다. 식생 종류에 관계없이 $25^{\circ}C$ 칼럼의 T-N 용출이 급격히 증가한 시기는 $5^{\circ}C$ 칼럼에서 보다 더 빠른 시기에 나타났다. 이삭사초의 침수 후 60일째 T-P 용출량은 $5^{\circ}C$ 조건에서 $5.7mg\;L^{-1}$이었으며, $25^{\circ}C$ 조건에서 $8.7mg\;L^{-1}$이었다. 물억새의 침수 후 60일째 T-P 용출량은 $5^{\circ}C$ 조건에서 $7.1mg\;L^{-1}$이었으며 $25^{\circ}C$ 조건에서 $8.2mg\;L^{-1}$이었다. 식생 종류에 관계없이 $25^{\circ}C$ 칼럼의 T-P 용출이 급격히 증가한 시기는 $5^{\circ}C$ 칼럼에서 보다 더 빠른 시기에 나타났다. $25^{\circ}C$로 유지된 칼럼의 COD, T-N 및 T-P 용출량은 전반적으로 $5^{\circ}C$로 유지된 칼럼에 비해 높았다.

• 한국환경복원기술학회지
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• 제11권3호
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• pp.107-115
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• 2008

Herbs and plants widely used for the ecological restoration were selected for germination rate analysis under treatment of microorganisms to determine ideal treatment conditions and medium for enhanced germination rate. Albizzia julibrissin, when submerged in a nutrient medium or distilled water, presented a decrease in germination period rather than increase in germination rate. When treated with microorganism culture solution (JM-2) for 24 hours, 90% germination was achieved in two days, which is sufficient evidence to conclude that such treatment accelerates the germination of Albizzia julibrissin. Germination period decreased for Lespedeza cyrtobotrya samples submerged in microorganism solution for 15 and 48 hours, however, increases in germination rates were not observed. Sample treated in the solution for 24 hours had increased germination rate and enhanced germination period. Microorganism solution treatment had a negative effect on germination for Lespedeza cuneata, unlike Lespedeza cyrtobotrya and Albizzia julibrissin. Microorganism treated seeds of Lepsedeza cuneata had a lower germination rate than that of the control with no treatment. However, submerging treatments in a nutrient medium or distilled water for 24 to 48 hours were proven effective with higher germination rates than control sample with no treatment. Herbs and plants widely used for the ecological restoration were selected for germination rate analysis under treatment of microorganisms to determine ideal treatment conditions and medium for enhanced germination rate. Albizzia julibrissin, when submerged in a nutrient medium or distilled water, presented a decrease in germination period rather than increase in germination rate. When treated with microorganism culture solution (JM-2) for 24 hours, 90% germination was achieved in two days, which is sufficient evidence to conclude that such treatment accelerates the germination of Albizzia julibrissin. Germination period decreased for Lespedeza cyrtobotrya samples submerged in microorganism solution for 15 and 48 hours, however, increases in germination rates were not observed. Sample treated in the solution for 24 hours had increased germination rate and enhanced germination period. Microorganism solution treatment had a negative effect on germination for Lespedeza cuneata, unlike Lespedeza cyrtobotrya and Albizzia julibrissin. Microorganism treated seeds of Lepsedeza cuneata had a lower germination rate than that of the control with no treatment. However, submerging treatments in a nutrient medium or distilled water for 24 to 48 hours were proven effective with higher germination rates than control sample with no treatment.