• Journal of the Korean Society for information Management
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• v.23 no.4 s.62
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• pp.111-128
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• 2006

The purpose of this study is to measure economic value of full-text information services in order to determine whether it is worth for libraries to invest a large amount of money in constructing database to begin with. The study applied an contingent valuation method to measure its economic value. The imaginary scenarios are designed for estimation the value of Non-market-goods, estimation in advance and experts investigation are needed for rising the confidence level, double-bounded dichotomous choice is chosen in question method. The use value, which one user is willing to pay for domestic monograph full-text information services, was 836 won per one monograph. And, the annual non-use value was 236 won. The total annual economic value of all the students was 831 billion won.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.8 no.4
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• pp.1-69
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• 1997

국립기술품질원은 최근 전기용품안전관리법에 의한 전기용품기술기준의 내용 중 전자파장해와 관련된 시험기준 및 측정방법을 대폭 개정하였다. 이 개정은 국립기술품질원 고시 제 1997-140호(1997. 7. 9.)에 의해 이루어졌는데 개정내용의 주요골자는 기존 전자파장해 분야의 기준 및 측정방법을 전면적으로 수정, 보완하고 전자파내성분야의 기준 및 측정방법을 신규로 추가 삽입한 것으로 판단된다. 주지하다시피 전자파장해와 관련해서 우리나라의 국가규격은 전파법에 의한 기술규격과 전기용품 안전관리법에 의한 기술규격으로 양분화되어 있다. 전파법에 의한 기술규격은 작년에 정보통신부 고시 제1996-78, -79, -80, -81호(1996. 10. 9.)에 의해 종전의 전자파장해검정규칙에 따른 시험방법을 CISPR에 의한 모든 대상기기에 대해 전자파장해 및 전자파내성 관련 기술기준 및 시험방법을 대폭 개정한바 있으며, 본 전기용품안전관리법에 의한 기술기준 개정은 전자파장해 및 내성에 관련 내용을 최근의 국제기술동향에 부응하도록 망라하여 정리한 것이라는 관점에서는 전파법에 의한 개정내용과 유사한 것으로 여겨지나, 다만 그 대상기기가 전기 용품으로 한정된 것이 다른 것으로 사료된다. 종전의 전기용품안전관리법에 의한 전자파장해 기술규격은 국제규격인 CISPR의 권고사항을 따르되, 국내 산업계의 의견을 반영하여 측정주파수 범위, 기술기준, 측정방법 등의 내용에 있어서 다소의 수정을 가하였으며, 정보기술기기에 대해서는 미국의 FCC기술기준을 위주로 하여 제정된 것이었다. 금번 기술기준 개정은 전자파장해 분야에 있어서 이와 같은 종전의 기술기준을 최초의 CISPR 기술동향을 최대한 여과없이 반영시키도록 수정하였으며, 전자파내성 분야에 대해서는 전체적으로 IEC 1000-4-Series의 내용을 기본으로 하였으나, 여기에 추가적으로 디지털 무선전화기에 대한 방사내성 시험항목을 ENV55024의 내용을 위주로 하여 신규로 작성한 것으로 볼 수 있다. 따라서 기술기준의 개정사항은 주로 전자파장해 분야로 국한되어 있으며, 전자파내성 분야는 신규 제정한 것으로서 본고에서는 종전의 기술기준에서 전자파장해분야의 변경사항과 신규로 제정된 전자파내성 측정방법과 시험기준을 소개하는 거승로 하겠다.

• Asian Journal of Turfgrass Science
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• v.19 no.1
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• pp.1-16
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• 2005

This study was conducted to effect a complex fertilizer treatment on a recovery of damaged turfgrass caused by competing with tree at area under trees, and to seek for effective management system on damaged areas under trees in golf courses. Available phosphorous and potassium were enough to grow up turfgrass in plots of East valley and Ji San Golf Club. But these plots were acid soil ranged from pH 5.3 to pH 5.5, so that lime fertilizer was required for improving the chemical of soil. The effect on complex fertilizer showed significant f3r the recovery of damaged turfgrass. Turfgrass recovery ratio by complex fertilizer was better in low-density(LD) section of fertilizer than in high-density(HD) section of control. As the result of surveying turfgrass characters according to dates, dry matters in HD sections of control plots were higher than these in LD sections of fertilizer plots in 6 Aug. before sprinkling a complex fertilizer. But dry matters in LD section of fertilizer were, on the contrary, higher than in 6 Sep. after sprinkling complex fertilizer. In view of the result so far conducted, a turfgrass recovery to LD sections of complex fertilizer was batter than that of HD sections of control. Sprinkling complex fertilizer on turfgrass damaged by competing with trees will maintain the turfgrass growth, even though happen to compete between trees and turfgrass.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.210-216
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• 2010

This study was carried out to investigate the plant growth of various foliage plants affected by the nutrient solution strength. Ficus benjamina, Hedera helix, Philodendron tatei, Rhapis excelsa, Spathiphyllum spp. were used in this experiment. The Sonneveld solution was diluted to 0, 1/4, 1/2, and 1 folds and applied through a subirrigation system. Plant height and width, leaf number, leaf area, fresh and dry weights of shoots were measured to compare the responses to the different treatments. The required amounts for nutrients were different among the various foliage plants. The growth of Ficus and Philodendron was improved as the nutrient solution strength got higher, but that of Hedera and Spathiphyllum showed the best growth in the lower nutrient solution strength of 1/4 and 1/2 folds. The growth of Rhapis was improved in the nutrient solution strength of 1 fold but the other treatments did not affect on plant growth. N, P, and K were the most important nutrients that had influence on the growth of the foliage plants in this study. There was not an accurate criterion for fertilization and irrigation to each foliage plant. Moreover, the foliage plants grew slowly during the early stage and this period must be shortened for commercial production. Therefore, the experiment was executed to make up these defects. The plants applied with proper strength of Sonneveld solution grew faster and had better quality.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.317-321
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• 2012

This study was carried out to investigate the effect of EC levels in nutrient solution on the growth of rose in coir substrate during the juvenile. Nutrient concentration were EC 0.6, 1.0, 1.4, and $1.8dS{\cdot}m^{-1}$. In spite of high concentration of nutrient solution was supplied, EC and inorganic ions content in the extract of substrate was no difference by 22 days after planting. After that, they was rapidly increased with higher concentration of nutrient solution. Number of shoot was highest in EC $1.8dS{\cdot}m^{-1}$ at 2nd growth cycle, 90 days after planting, after that was showed a tendency to increase with increasing nutrient concentration, but was no significant difference among treatment except EC $0.6dS{\cdot}m^{-1}$. Judging by results of growth of rose and contents of inorganic ion in extracts of media, our experiment suggests that the suitable nutrient concentration is EC $1.8dS{\cdot}m^{-1}$ until 90 days and then EC $1.4dS{\cdot}m^{-1}$ until 165 days after planting that is more higher than conventional nutrient concentration for absorption by coir.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.715-725
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• 2017

Importance of climate change and its impact on agriculture and environment has increased with the rise in the levels of Green House Gases (GHGs) in the atmosphere. To slow down the speed of climate change, numerous efforts have been applied in industrial sectors to reduce GHGs emission and to enhance carbon storage. In the agricultural sector, several types of research have been performed with emphasis on GHGs emission reduction; however, only a few work has been done in understanding the role of carbon sink on reduction in GHGs emission. In this study, we investigated ecosystem carbon balance and soil carbon storage in an agricultural paddy field. The results obtained were as follows: 1) Evaluation of soil C sequestration in paddy field was average $3.88Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, average $3.22Mg\;C\;ha^{-1}$ following NPK+hairy vetch treatment, and average $1.97Mg\;CO_2\;ha^{-1}$ following NPK treatment; and 2) Net ecosystem production (NEP) during the paddy growing season was average $14.01Mg\;CO_2\;ha^{-1}$ following NPK+hairy vetch treatment, average $12.60Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, and average $11.31Mg\;CO_2\;ha^{-1}$ following NPK treatment. Therefore, it is proposed that organic matter treatment can lead to an increase in soil organic carbon accumulation and carbon sock of crop ecosystem in fields compared to chemical fertilizers.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.6
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• pp.15-25
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• 2018

This study was conducted to obtain proper amount of solid poultry manure in the beginning phase of Deutzia crenata growth. Seedling growth increment, dry weight, inorganic matter uptake and chemical changes of soil according to the concentration of solid poultry manure fertilization. 1. When treated with solid poultry manure, seed germination rate was highest on the control. However, germination rates tended to decrease when treated with at high concentrations. 2. The growth of seedlings treated with poultry manure was always higher than that in control. At the 1.0% of poultry manure treatment, the growth rate and dry weight of the seedlings was highest. 3. The amount of inorganic nutrients absorbed by the seedling was generally high with the 1.0% treatment, declined sharply with the 2.0% treatment. 4. For the planting soil of Deutzia crenata, the higher the concentration of poultry manure, the lower the soil pH. However, nitrogen, available P, K, Na and Mg contents in the soil have increased with higher concentrations.

• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.161-168
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• 2017

BACKGROUND: Rabbiteye blueberry(Vaccinium ashei Reade) has low nutrient uptake efficiency due to its shallow and fibrous root system without root hairs. This study was carried out to establish an efficient nutrient application standard by investigating the effect of nitrogen fertigation on the growth and fruit characteristics of rabbiteye blueberry. METHODS AND RESULTS: 'Brightwell' rabbiteye blueberry was treated with 0, 50, 100 and 200% nitrogen fertigation of recommended fertilizer application (6, 9 and 14 g/bush in the first, second and third years, respectively). The results showed that leaf nitrogen content significantly correlated with the fruit weight and fruit yield. However, canopy area, dry weight, sugar and anthocyanin contents did not correlate significantly with the leaf nitrogen content. The leaf and stem dry weights of 'Brightwell' rabbiteye blueberry during the third year of planting were the highest with 50% nitrogen fertigation (leaf dry weight=723.7 g/bush; stem dry weight=890.7 g/bush). Maximum fruit yield of 'Brightwell' rabbiteye blueberry (12.9 kg/bush) was observed during the third year of planting with 50% nitrogen fertigation and this was about 70% greater than the treatment that received no nitrogen fertigation. The fruit yields of 'Brightwell' rabbiteye blueberry during the third year of planting treated with 100 and 200% nitrogen fertigation were 11.0 and 11.5 kg/bush, and these were 17 and 12%lower than the 50% nitrogen fertigation treatment, respectively. Further, the efficiency of nitrogen utilization was the highest (90%) with 50% nitrogen fertigation and lowest (18%) with 200% nitrogen fertigation. CONCLUSION: The results of this study suggests that fertigation with 50% of the recommended fertilizer could be most effective for enhancing the growth and nitrogen use efficiency of rabbiteye blueberry.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.2
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• pp.155-163
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• 1999

Nutrient balance during rice cultivation in the paddy of a local area under the environmental protection for drinking water supply was investigated. To compare nutrient balance in the paddy soil applied with different types of fertilization, 7 treatments were selected as followings : Recommended level of chemical fertilizers(R), Conventional fertilization(CF), Fresh cow manure(FCM), Cow manure compost(CMC), Straw compost+reduced chemical fertilizer(SCF), Fresh straw+recommended level of fertilizers(FSC), and no fertilization as control(C). Here, FCM, CMC and SCF were applied at the same level of total nitrogen as recommended in R. Rice yield was the highest in the recommendation(R) and fresh cow manure (FCM) treatments with $6,730kg\;ha^{-1}$(index 100), and followed by SCF (index 98), FSC (index 98), CMC(index 94), and CF(index 94). But statistically significant difference was not recognized among treatments except the control. Nitrogen infiltration loss was high in the simple chemical fertilizer treatments with $63kg\;ha^{-1}$ in CF and $58kg\;ha^{-1}$ in R during rice cultivation, respectively. Nitrogen infiltration loss was decreased below half level of chemical fertilizer treatments with cow manure treatments ($23kg\;ha^{-1}$ in FCM and $27kg\;ha^{-1}$ in CMC) and with reducing chemical fertilizer treatment by adding straw compost ($25kg\;ha^{-1}$). Phosphate was not leached during rice cultivation in paddy soil of a fluvial deposit type, in which oxidation horizon was developed broadly under around 15 cm depth of surface soil. Phosphate balance (A-B) was closed to 0 in all treatments except cow manure treatment (CMC), in which it was $+30kg\;ha^{-1}$ and show the possibility of over accumulation of phosphate by continuously replicated application of cow manure compost. Potassium balance was negative value in all but straw recycling treatment (FSC). It means that potassium was continuously supplied from soil minerals, uptaken by plants or eluted out of soil. In conclusion, by substituting inorganic fertilizer for organic fertilizer or reducing application rate of chemical fertilizer through mixing organic fertilizer, it would be possible to achieve the same rice yield as in the recommendation treatment and to decrease nutrient leaching below half level in rice paddy soil.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.4
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• pp.77-85
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• 2020

This study analyzes the effects of mixed fermented organic fertilizer on chinese cabbage growth and soil properties in order to investigate the nutritional effects of organic fertilizers, which are developed as an alternative fertilizer for imported castor oil cake. In this study, four treatments were set up: 100% and 200% rate of nitrogen application (320 kg ha-1 for Chinese cabbage) on mixed fermented organic fertilizer A(FA) and mixed fermented organic fertilizer B(FB), respectively, 100% rates of the mixed expeller cake (MEC) fertilizer, and the untreated control. Results revealed that the growth and yield of Chinese cabbage increased as more fermented organic fertilizer was used. However, while there were no significant differences in growth characteristics between treatments of 100% rate of mixed fermented organic fertilizer and 100% rate of MEC, the impacts on yields resulted similar. The nitrogen use efficiency (NUE) of Chinese cabbage was measured a range of 20-31% depending on the response to treatment. The 100% FA showed the same as NUE and nitrogen absorption with 100% rate of MEC. Regarding soil properties after cultivation, there were no significant differences among the effects of fertilizers in pH, EC, soil organic matter, and available phosphate. However, the content of exchangeable cations(K, Ca, Mg) was higher in areas treated with mixed fermented organic fertilizer than in untreated areas. Furthermore, the bacterial population density in the soil was higher in areas treated with mixed fermented organic fertilizer than in untreated areas and increased as more mixed fermented organic fertilizer was used. There were no significant differences in the population density of actinomycetes and fungi when fertilizer was applied to the soil. These results also show that FA, as a alternative organic fertilizer for imported castor oil cake, has similar nutritional effects as that of MEC. Therefore, further research the appropriate amounts of fertilizer is required to achieve economical and eco-friendly nutrient management.