• Korean Journal of Environment and Ecology
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• v.27 no.1
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• pp.64-70
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• 2013

To examine the proportion of secondary seed dispersion by wildlife and to identify the related wildlife, We measured seed removal rates and related wildlife at the natural mixed broadleaved forest in mountain Jungwang, Pyeungchang-gun in middle part of Korean peninsula, seed-tray contained four kind of tree seeds were setted from mid-september to late-October for three years. Mean seed removal rates(MSRR) of acorn(Q. mongolica)is shown the highest values 87.2%, next MSRR of samara(A. pseudosieboldianum) does 33.1%, MSRR of samara(A. pictum subsp. mono) does 29.2%. and then SRR of samara(A. mandshuricum) does only 13.6%. Acorns are removed more faster than samaras. Among the related wildlife, Siberian chipmunks most freqently visit seed tray, and ordered Korean squirrel, Wild boar, and Yellow-throated marten. Most secondary dispersed acorns might be consumed by Wild boar, and small portions does comsumed or scatter-hoarded by rodents. Most secondary dispersed samaras might be consumed by rodents, and small portions does scatter-hoarded by rodents. A few sound seeds are remained on the forest floor in late October owing to the seed consunption and seed hoarding by wildlife. We observe seedling establishment of four broadleaved tree species. From these results, We proved Wild boar is seed comsummer, and rodents are seed consummer and seed disperser. Further studies on secondary seed dispersion, seed consumption and hoarding and related wildlife should be needed.

• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.212-217
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• 2003

This study was conducted to search for possible cultivation area of Rhodiola sachalinensis as well as to obtain the basic information of growth characteristics. One­year old nursery plants of Rhodiola sachalinensis were collected from Yonbyeon Hongkyungcheon development society in China This expriment was evaluted in three areas according to sea level such as plain region in Cheongwon(50m at sea level), mid­mountainous region in Jecheon(350m at sea level) mountainous region in Banyans(650m at sea level). The growth status Rhodiola sachalinensis showed wide range of variation in there areas. Plant height showed from 8.1cm to 15.8cm, number of branch showed from 3.1 eachs to 4.6 eachs and rate of withering showed from 76％ to 94％, respectively. It was increased rapidly at the early August caused by summer depression. Flowering period of Rhodiola sachalinensis was shown at around middle and late June, total duration of flowering showed from 12 to 13 days and flower colors were various as brown, dark purple, yellow green and brown red color.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.939-949
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• 2020

Currently, the demand for farmland is steadily decreasing due to changes in the agricultural environment and dietary life. In line with this, the government adopted an integrated water management with the enactment of the Framework Act on Water Management on June 2019. Therefore, it is required to take a closer look at agricultural water demand that accounts for 61% of water use for efficient water resources management. In this study, the overal process was evaluated for estimating agricultural water demand. More specifically, agricultural water demand for paddy field, which comprises 67% to 87% of agricultural water demand, was reviewed in detail. The biggest issue in estimating the paddy field water demand is the selection of the method for potential evapotranspiration. FAO recommends Penman-Monteith, but, currently, our criteria suggest a modified Penman equation that shows over estimation. Also, the crop coefficient, which is the main factor in evaluating evapotranspiration, has an issue that does not consider the current climate and crop varieties because it was developed 23 years ago. Comparing the Modified Penman and Penman-Monteith equations using the data from Jeonju National Weather Service, the modified Penman equation showed a big difference compared to the Penman-Monteith equation. When the crop coefficient was applied, the difference between late May and late August increased, where the amount of evapotranspiration was high. The estimation process was applied to four study reservoirs in Gimje. Comparing the estimated water demand with the supplied water record from reservoirs, the results showed that the estimation accuracy depends on not just the potential evapotranspiration, but also the standard water storing level in paddy fields.

• Journal of Chest Surgery
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• v.39 no.3 s.260
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• pp.194-200
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• 2006

Background: Thoracoabdominal aortic replacement is an extensive operation that opens both the pleural cavity and abdominal cavity, which has high mortality and morbidity rate. The authors have reported 9 cases of the thoracoabdominal aortic replacement in 2001. Since 2003 we have applied the deep hypothermic circulatory arrest to the Crawford type I and II thoracoabdominal aortic replacement. Therefore, we analysed the effect of the changes in operative techniques. Material and Method: Between 1996 and 2005, we have performed 20 cases of thoracoabdominal aortic replacement. The underlying diseases were 8 cases of atherosclerotic aneurysm with 4 cases of ruptured aneurysm and 12 cases of aortic dissection with 10 cases of a previous operations. According to Crawford classification, there were 2 cases of type I, 7 cases of type II, 1 case of type III, 7 cases of type IV, and 3 cases of type V. We compaired the results of the patients who underwent thoracoabdmoninal replacement before 2001 which already has been reported and after then. Result: Before 2001 we have performed 9 cases of thoracoabdominal replacement and 5 patients were died of the operation. All three patients with type I and II were died. There was no case of thoracoabdominal replacement between 2001 and 2002, but after 2003 we have performed 11 cases of thoracoabdominal replacement which involved 1 case of type I, 5 cases of type II, 1 case of type III, 2 cases of type IV and 2 cases of type V. There was no mortality and no fetal complications. Conclusion: The deep hypothermic circulatory arrest is a safe method of extended thoracoabdominal aortic replacement.

• Korean Journal of Weed Science
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• v.31 no.1
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• pp.84-88
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• 2011

This study was established to investigate the effects of seeding depth and seeding time on the emergence, growth, and N production of Vicia tetrasperma and V. hirsuta in 2007 and 2008. All seeds of both species were gathered from Dangjin, Chungnam in late June of 2005 and stored for two year at room temperature. Both V. species began to germinate at the end of June, passed the winter with the seedling stage, rapidly increased their height in April and May, were in full bloom in May, and then withered after entering mid-June. V. hirsuta had higher emergence rate and growth compared to those of V. tetrasperma. The optimum seeding time and seeding depth for a cover cropping was from late August to early September and from 1 to 5 cm, respectively. V. tetrasperma and V. hirsuta had a satisfactory growth and provided 43.8 and $55.4kg\;ha^{-1}$of N, respectively.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.789-795
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• 2015

The new garden chrysanthemum (Dendranthema grandiflorum Ramat.) cultivar 'Nuri Ball' was developed at Yesan Chrysanthemum Experiment Station of Chungcheongnam-do Agricultural Research and Extension Services in 2011. 'Nuri Ball' was bred through a cross between the '02-145-01' line as the female parent with yellow flower color and '02-04-32' as the male plant with white flower color in 2004. Three years of adaptation trials were conducted from 2006 to 2009 under natural conditions. This study compared the external shape type with that of 'White Miri' and conducted ploidy and RAPD (Random amplified polymorphic DNA) marker analyses. These tests showed that 'Nuri Ball' cultivar has its own characteristics compared with the control 'White Miri'. 'Nuri Ball' was a shrub type variety with semi-double flowers of 4.0 cm in width with white petals. It could produce 1025.2 flowers per plant in autumn. Compared with the control 'White Miri', 'Nuri Ball' was similar in terms of shape and color of flowers, but was different in flower size and number. The natural flowering time of 'Nuri Ball' was late September. It had very vigorous growth and an early budding plant. 'Nuri Ball' was demonstrated to be a new cultivar based on ploidy test and RAPD analysis. 'Nuri Ball' is intended for use as a bed chrysanthemum and expected to contribute to farm incomes in landscaping.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.1
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• pp.17-23
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• 2019

This experiment was carried out to evaluate the characteristic and productivity of forage corn varieties sown at the last ten days of May at Cheonan of Korea on 2017 and 2018. Forage corn varieties sown on 24th May 2017 and $25^{th}$ May 2018 were emerged in 5th and 1st June, respectively. Silking date of forage corns was different among varieties(p<0.05). Stem length of forage corns was not different among the varieties, except Kwangpyeongok(KPA) and Nero IT. Stem diameter of forage corns was not different amaong the varieties. Outbreak rate of black streaked dwarf virus was lower than 3% in all varieties. Total digestible nutrient(TDN) yield was different among corn varieties(p<0.05), which was higher in P32P75, followed by P2088, P31N27, and KPA. The TDN yield of varieties had direct correlation with stem length, stem diameter and ear yield, respectively(p<0.01). Average of TDN in all varieties was 69.8%. These results suggested that forage corn variety with late-seeding adaptability is more important for increasing the productivity of forage corn If harvesting of winter forage crops have to be finished in the middle ten days of May in middle region of Korea.

• Korean Journal of Plant Resources
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• v.32 no.1
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• pp.38-44
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• 2019

This study was conducted to establish a domestic cultivation system of a newly introduced yam bean (Pachyrhizus erosus L.). Growth and yield were investigated in response to various cultural practices, such as seedling raising, planting distance, pinching, and flower pruning. Optimum conditions for raising of seedling were an average temperature of $22^{\circ}C$ for 30 days. Considering of the raising efficiency and the convenience of transplanting, 128 cells per tray was a suitable size. When pinching at a height of 120 cm from late July to early August, yield increased by 22% compared to no pinching. Flower pruning between late August and early September increased the number of tubers and tuber yield by 32% in comparison with no flower pruning. Yam bean seedlings planted at $50cm{\times}30cm$ spacing resulted in 30% yield increase as compared to wider spacing of $100cm{\times}30cm$. Our results thus suggested that the optimal combination of cultural practices ($50{\times}30cm$ planting distance, pinching at 120 cm height, and one time of flower pruning) increase profitability by 107%. All these results suggest high possibility of yam bean as a new income crop in Korea.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.266-273
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• 2019

Heavy metal contamination in freshwater ecosystem has been receiving increased worldwide attention due to their direct or indirect effect on human health and aquatic organisms. In this study, we investigated biological effects such as survival rate, growth rate, emergence rate, sex ratio and mouthpart deformity of Chironomus plumosus. The survival rate of C. plumosus decreased with the increase in heavy metal concentration as well as exposure time after cadmium (Cd) or zinc (Zn) exposure. The growth rate decreased at days 4 and 7 after Cd exposure and significantly reduced at the relatively high concentration of $50mg\;L^{-1}$ Cd. The emergence rate was decreased at $50mg\;L^{-1}$ Cd and $100mg\;L^{-1}$ Zn. The sex ratio showed imbalance pattern at relatively low concentrations (0.5 and $2mg\;L^{-1}$ Cd) with high proportion of male and relatively high concentration ($100mg\;L^{-1}$ Zn) with high proportion of female (60%). In addition, mentum deformities were observed at high concentration of Cd and Zn. These results suggest that heavy metal exposure in aquatic ecosystem may affect biological and morphological responses, and aquatic midge C. plumosus is a potential indicator for assessment of environmental pollutant such as heavy metals.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.555-561
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• 2019

This study analyzed the shipbuilding structure of House Tangerine over a ten day period and according to the month in Jeju. By estimating and analyzing the price flexibility function of House Tangerine, the aim was to determine if the shipment control can stabilize and increase the incomes of House Tangerine farmers and derive policy implications. The greatest decline in the coefficients of the ten-day price flexibility occurred in the equations from early June to late July. Therefore, the shipment control of House Tangerine is required more during early June and late July. The coefficient of DUM_Q, indicating the year in which the quality of House Tangerine is somewhat deteriorated, was statistically significant and had a (-) sign. The coefficients of DUM_SUK, indicating the year in which Chuseok (Korean Thanksgiving Day) was in October, was statistically significant and had a (-) sign in the middle and late October. The greatest decline in the coefficient of monthly price flexibility function occurred in July, June, and September. Therefore, shipment control is required more in July, June, and September. The (-) signs of the coefficients of DUM_Q and DUM_SUK suggest that the need for shipment control is more important when the quality is less than better quality and that the necessity of shipment control is required more when Chuseok is in October, respectively.