• 한국작물학회지
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• 제36권1호
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• pp.79-84
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• 1991

기계수확시 탈립된 종자들이 이듬해 발아 생장하여 휴경조건하에서 수량 및 수량구성 요소에 많은 변이를 보였기에 무경운 직파재배의 가능성을 타진하려 수도의 수량 및 수량구성요소를 조사하였고 또한 잡초종의 피도에 따른 수량변이를 상관계수를 통해 알아보았다. 무경운 무시비 조건에서도 단위면적당 최대 188kg/10a의 수량을 보여 입모확보가 보장된다면 무경운 직파재배는 가능할 것으로 판단되었다. 또한 성공적 무경운 직파를 위해서는 충분한 입모확보, 천이, 두과식물과의 적절한 혼파 초형개발에 관한 연구가 기대된다.

• 한국초지조사료학회지
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• 제11권3호
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• pp.169-174
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• 1991

For simple estimation of pasture production and nutritive value in relation to height of orchardgrass (Ductylis glomumtu L.), the experiment was carried out in a pasture mixture dominated by orchardgrass. The samples of grasses were harvested at the heights of about 30, 40, 50, 70 and 90 cm at the first harvest under different percentage of 100 (grass coverage): 0 (bareland), 80 : 20, 60 : 40, 40 : 60 and 20 : 80, respectively. As the height of orchardgrass was increased, fresh and dry matter (DM) yield were significantly increased. The regression equation between DM yield (Y) and height (X) was Y=ll. 5390 X- 146.60 (r=O. 9414 * * ). Also the higher bareland, the lower pasture production was observed. As the plant height at the first harvest was increased, the contents of crude (C) protein, C. fat, C. ash and relative feed value were markedly decreased. On the other hand, the contents of C. fiber, NFE, NDF. ADF, cellulose and lignin were significantly increased, respectively. The higher height, the lower DM digestibility was found. The equation between digestibility (Y) and height (X) was Y=- 0.2193 X+ 80.99 (r = - 0.9862**). Considering DM yield, digestibility and crude protein, the optimum height of orchardgrass at the first harvest was 59 to 67crn for better pasture production and nutritive value.

• 한국환경복원기술학회지
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• 제14권3호
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• pp.47-55
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• 2011

Cicada is a very familiar insect to people but habitat characteristics of them are not well known. To investigate habitat characteristics of cicada nymph, plant species, plant cover, soil hardness, accumulated organic mass, organic content in soil, and root density were investigated at 11 sites in an apartment complex garden in Seoul. Selected sites had different densities of cicada nymph case above the ground. Density of cicada nymph case was positively correlated with accumulated organic mass, organic content in soil, and root density and negatively correlated with soil hardness. Even though shrub coverage was not linearly correlated with the density of cicada nymph case, 80% cover of shrub was necessary for the high density of them. Data in this study suggested that organic matter in addition to root density be the primary limitation factor of cicada nymph and high amount of litter-fall decrease soil hardness through the increase of soil organic matter. This study suggests that the density of cicada nymph can be managed through organic content in soil.

• Journal of Plant Biology
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• 제35권3호
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• pp.205-210
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• 1992

한국산 나리속 7종 2변종에 대하여 광학현미경과 주사전자현미경으로 화분의 크기와 형태를 조사하였으며 이들의 진화경향성 및 계통을 고찰하였다. 이상의 조사 결과 한국산 나리속 식물은 2유형으로 구분할 수 있었다. 즉, 소망상형은 화분립의 크기와 망강의 크가가 비교적 작은 유형으로 하늘나리와 땅나리에서만 관찰되었고, 대망상형은 화분립의 크기와 망강의 크기가 비교적 큰 유형으로 그 밖의 모든 분류군에서 관찰되었는네, 소망상형이 대망상형보다 원시적인 것으로 생각된다. 또한 화분형질에서 소망상형으로 관찰된 하늘나리와 땅나리는 개화방향은 다르지만 린편, 화피편의 형태가 유사하므로, 이들을 개화방향에 따라 다른 절로 취급한 Wilson(1925)의 체계보다는 종자, 린편의 형태 등의 형질에 의해 같은 절로 취급한 Comber(1949)의 체계가 보다 타당한 것으로 생각되며, 이들을 같은 아절로서 취급해야 한다고 생각한다.

• Journal of Ecology and Environment
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• 제42권1호
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• pp.12-19
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• 2018

Background: The objective of this study was to determine the relationship between soil environmental factors and halophyte distribution in the west coast of South Korea. Soils of our study sites were categorized into two groups: salt marsh and estuary marsh. Results: Salinity was higher in the salt marsh group than that in the estuary marsh group. However, total nitrogen, silt, and clay contents were higher in the estuary marsh group than those in the salt marsh group. Although altitude had a wider range in the salt marsh group, the mean altitude was higher in the estuary marsh group than that in the salt marsh group. Annual halophytes of seed propagation species were distributed parallel to the coast line on salt marsh. Higher coverage of vegetation was found in the area closer to the coast line. Plant density was higher near dead parental plants in estuary marsh, showing less difference in area that was more distant from the coast line. Conclusions: Results of canonical correspondence analysis (CCA) for vegetation distribution and sediment environmental factors and germination analysis in the coast line showed significant relationship with halophyte distribution. Therefore, they can be used as an indicator of coastal plant movement due to sea level rise.

• 한국조경학회지
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• 제23권3호
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• pp.48-58
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• 1995

This study was conducted to investigate the plant community and to propose ecological planning methods for urban environmental forest on Gaepo neighborhood park, Gangnamgu in Seoul. Thirty-six plots that the size of each plot was 10$\times$10m(100\ulcorner) were set up and the vegetation analysis was carried out. Field survey was executed Apirl, 1994. The actual vegetation was consisted of Poplulus$\times$albaglandulosa community(73.03%), Robinia pseudoacacia community(8.30%) P. $\times$ albaglandulosa-R.pseudoacacia community(1.81%) and environmental forest (15.22%) in the survey site. According to mean importance values of each plot, survey area were divided into ten forest communities. As for the analysis of plant community structure which was classified into ten forest communities, the importance values, ecological diversity, number of species, number of individuals, basal area and crown coverage of urban environmental forest were relatively lower than those of the native community. In urban environmental forest of Gaepo neighborhood park, it showed problems for the planting method. So urban environmental forest should be constructed considering ecological characteristics based on above results.

• 한국환경복원기술학회지
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• 제14권4호
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• pp.55-66
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• 2011

The objective of this study was to investigate the possibility of seeding methods for quarry rehabilitation. To achieve the objective, the experiment was designed for rehabilitation of quarry with seed mixing types (woody type and herbaceous type) and forest topsoil. Seeds and seeding materials were applied to the quarry slope using hydroseeding measures. The study was conducted in limestone quarry (Lafarge Halla Cement Inc.) near Baekdu Daegan Mountain System at Okke, Kanwon-do. The experimental seedbed was set in 2007 and field investigation was carried out from 2007 to 2010. As the result of experiment, it was found that the early-phase pattern for surveyed species to establish was affected by the soil mixture types. The mixture type of herbaceous seeds resulted in the higher plant coverage than the woody seeds. The application of forest topsoil showed a potential increase the plant diversity, but it was affected by mixing seeds. Naturally-emerged species as Alnus hirsuta, Quercus mongolica will be useful for rehabilitation at the quarry and damaged slopes.

• Journal of Microbiology and Biotechnology
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• 제16권10호
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• pp.1650-1655
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• 2006

Bacteria belonging to the genus Paenibacillus are facultatively anaerobic endospore formers and are attracting growing ecological and agricultural interest, yet their genome information is very limited. The present study surveyed the genomic features of P. polymyxa ATCC $842^T$ using pulse-field gel electrophoresis of restriction fragments and sample genome sequencing of 1,747 reads (approximately 17.5% coverage of the genome). Putative functions were assigned to more than 60% of the sequences. Functional classification of the sequences showed a similar pattern to that of B. subtilis. Sequence analysis suggests nitrogen fixation and antibiotic production by P. polymyxa ATCC $842^T$, which may explain its plant growth-promoting effects.

• 아시안잔디학회지
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• 제5권2호
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• pp.69-73
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• 1991

This experiment was carried out in order to study the effect of nitrogen fertilization on the growth of Colonial bentgrass and thatch accumulation under no removing clipping residues. Nitrogen fertilization was applied as 4 levels, 10, 20, 25 and 20gN/m$^2$, respectively. The results were as follows : 1.Response of plant length and dry weight of thatch to N fertilization were significant differences between N levels. It suggested that N fertilization with no clipping residues greatly affected to the growth and thatch accumulation of colonial bentgrass.2.Plant length, the dry weight of clipping residues and coverage were obtained the highest values at 20g N. It was assumed that 20gN/m$^2$ is the limiting N level to obtain the favorable growth of Colonial bentgrass. 3.The dry weight of thatch and lignin content were increased with high nitrogen fertilization level. 4.The dry weight of thatch indicated positive significant correlation with lignin content. 5. The dry weight of thatch per N(THg/N) at 20g~25g/m$^2$ levels were obtained the lowest values than of other levels of N. It may be due to the stimulating of microbial activity by adequate to N fertilizers which increased mineralization of thatch.

• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1246-1254
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• 2018

The importance of performing Level 3 probabilistic safety assessments (PSA) along with a general interest in assessing multi-unit risk has been sharply increasing after the Fukushima Daiichi nuclear power plant (NPP) accident. However, relatively few studies on multi-unit Level 3 PSA have been performed to date, reflecting limited scenarios of multi-unit accidents with higher priority. The major difficulty to carry out a multi-unit Level 3 PSA lies in the exponentially increasing number of multi-unit accident combinations, as different source terms can be released from each NPP unit; indeed, building consequence models for the astronomical number of accident scenarios is simply impractical. In this study, a new approach has been developed that employs the look-up table method to cover every multi-unit accident scenario. Consequence results for each scenario can be found on the table, established with a practical amount of effort, and can be matched to the frequency of the scenario. Preliminary application to a six-unit NPP site was carried out, where it was found that the difference between full-coverage and cut-off cases could be considerably high and therefore influence the total risk. Additional studies should be performed to fine tune the details and overcome the limitations of the approach.