• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.73-78
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• 2011

This study was conducted to evaluate the effect of developed SCB (DSCB) liquid fertilizer produced by adding N, P and K at SCB liquid fertilizer on the growth of kentucky bluegrass. Two different N sources used in DSCB were ammonium sulfate (DSCB-A) and urea (DSCB-U), respectively. Fertilizer treatments were designed as follows; non-fertilizer (NF), control (CF; chemical fertilizer), DSCB-A1 ($200\;ml{\cdot}m^{-2}$DSCB-A), OSCB-A2 ($250\;ml{\cdot}m^{-2}$DSCB-A), OSCB-U ($250\;ml{\cdot}m^{-2}$DSCB-U) and CF+SCB (CF+$250\;ml{\cdot}m^{-2}$SCB). Every treatment was arranged in a randomized complete block design with three replications. In kentucky bluegrass, turf color index, chlorophyll index, dry weight and nutrient contents were measured. Results were as follows; It was hardly affected by DSCB and SCB application in investigation of chemical properties of soil. Turf color index and chlorophyll index in DSCB and SCB treatments were increased by 1~2% and 19~24% than NF, respectively and similar to CF. As applied with DSCB and SCB, dry weight of DSCB-U and CF+SCB was increased by 36% and 10% than CF, respectively, but similar to that of OSCB-A1 and DSCB-A2. Evaluated with turf quality and growth, DSCB-U was the best in all treatment and OSCB-A1 the most efficient. These results indicated that applications of OSCB and SCB promoted turf quality and growth of kentucky bluegrass or similar to CF, so that they were expected to replace chemical fertilizers.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.62-65
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• 2001

담수와 해수가 혼합되는 환경에서 퇴적 저니로부터의 오염 물질 용출률을 조사하였다. 축산폐수와 산업폐수의 영향을 받은 두 지점의 퇴적저니 시료에 대해 해수와 담수로 장기(약4주) 용출 시험을 행한 결과, 해수보다는 담수에서의 오염물질(영양염류 및 중금속) 용출률이 높은 것으로 조사되었는데, 이는 담수에서의 이온강도(ionic strength)가 상대적으로 낮아 오염성분의 포화농도가 높기 때문인 것으로 판단된다. 또한, 용존산소의 농도를 달리하여 시험한 결과 무산소 상태에서의 용출률이 호기성 상태에서 보다 높은 것으로 나타났으며, 그 원인이 생물학적인 것인지 화학적인 것인지는 밝혀지지 않았다. 시험결과를 종합해 볼 때 무산소 상태의 담수에서 오염물질의 용출이 극대화되며, 따라서 강어귀 등과 같이 유속이 작아져 오염물질의 침강은 잘되는 반면 오염물질의 해수에 의한 희석 효과는 적은 경우가 저니로 인한 수질 환경영향이 가장 클 것으로 예측된다.

• Korean Journal of Materials Research
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• v.5 no.5
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• pp.532-543
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• 1995

박용 디젤엔진 부품 크랭크샤프트의 기계적 성질에 미치는 화학 성분과 열처리 공정의 영향을 인장시험기, 경도시험기, 충격시험기와 광학현미경으로 조사연구하였다. 시행된 4가지 열처리공정중 다음의 열처리 공정인 노말라이징$\longrightarrow$TR단조$\longrightarrow$\ulcorner칭$\longrightarrow$템퍼링이 최적의 기계적 성질을 나타냈다. 이때 기계적인 성질은 오스테나이트 결정입도 크기, 냉각 속도, 오스테나이트화 온도와 오스테나이트화 유지 시간에 의존하였다. 오스테나이트 결정입도는 TR단조 후의 초기 결정입도 크기에 의존하고, 냉각 속도는 C-곡선 Nose를 지나야 하고, 오스테나이트화 온도는 탄소 함량에 의존하고 그리고 오스테나이트화 유지 시간은 저어널지름에 의존하는 것으로 나타났다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3C
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• pp.159-165
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• 2010

The problems such as natural resource exhaustion, pollutant emission and waste generation are increasing worldwide with the industrial development. The quantity of the industrial by-product in Korea is 6 million tons a year, and even its basic treatment processes including landfill, incineration and storage have reached their limits. In this study, fly ash and silica fume were applied to shotcrete to develop a method for the reuse of resources and to increase the use of fly ash, which is an industrial waste. An environmental hazard evaluation is a must to actively address the worldwide environmental problems, though. Therefore, an environmental impact assessment was conducted using the chemical content analysis test and heavy metal exudation test, for ten mixtures that were obtained through the pre-mixing and compressive strength tests. The results of the compressive strength test showed that all mixtures satisfied national and international standards. Cr, Cd and Hg were not detected, and Pb was detected only in some cases with fly ash. Cu and As were detected in all mixtures, but all of them satisfied national and international standards.

• 연구논문집
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• s.23
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• pp.141-153
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• 1993

본 연구는 국내의 플랜지 전문생산업체에서 제작하여 국외의 정유회사로 공급한 플랜지중 1개가 수압시험중 균열이 발생되어, 이에 대한 원인규명을 하고자 하였다. 먼저 균열이 간 플랜지와 동일재질의 건전한 플랜지를 입수하여 화학성분분석, 기계적 성질, 개재물, 경도측정 및 미세조직관찰을 통하여 비교조사하였고 파괴플랜지 용접부의 조직 및 경도측정으로 용접부의 영향을 조사하였다. 또한 파괴면의 육안관찰, SEM, EPMA 및 XRD분석으로써 균열발생 시기와 상태등을 추정하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.spc
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• pp.33-39
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• 2009

The practice of supplying nutrients for paddy soil with sustaining human health and ecological soundness is to utilize indicators considering soil chemical reactions. The long-term basis experiment of fertilizer and amendment of paddy soil and an experiment of yield response of soil types on nitrogen level from 2000 till 2002were used to search indicators of nutrient supplying capacity related to soil chemical reactions. Chemical reactions of paddy soil was composed of dissociating and/or adsorbing nutrients and of decomposing soil organic matter (SOM) into $H^+$, $e^-$, $CO_2$ in paddy soil. The indicators of nutrient supplying capacity, which were established by considering soil chemical reactions, were SOM or soil protein for nitrogen and available phosphate for phosphorus and cation exchangeable capacity (CEC) and exchangeable potassium for potassium. Korea has used fertilizer recommendation equations established with the indicators of nutrient supplying capacity for paddy soil.

• Korean Journal of Environmental Agriculture
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• v.29 no.1
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• pp.54-60
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• 2010

We have researched the changes in nutrient content in each phase of fermentation in crops treated with liquefied pig fertilizer, and have determined the best method for applying livestock excrement to cultured crops. In the execution of this experiment, rice was cultivated to full maturity at a paddy field in Jeollabuk-Do Agriculture Research and Extension Services(Jeon-buk series) from 2007 to 2008. The rice plant nitrogen absorption quantity change, according to the growth stages of the cultivated rice, was 20.3% in the rice treated with the liquid pig manure and 22.2% the chemical fertilizer at highest congelation. The chemical fertilizer showed a higher absorption quantity than the liquid manure compost. The nitrogen density at highest congelation was 1.5% in the chemical fertilizer, and 1.8% in the pig manure liquid compost not a significant difference. The stem height at harvest time was 73.8 cm in the crops treated with the liquid pig manure compost. Those treated with the chemical fertilizer, yielded a height of 4.2 cm less than the crops treated with the liquid pig manure compost. The yield was 507 kg/10a in the liquid pig manure compost treated rice, compared with the chemical fertilizer, which showed a value of 1.2% lower. The protein content was 6.3% in the rice treated with the chemical fertilizer, but 6.4% in the rice treated with the liquid pig manure compost. This is not a significant difference. However, the lodging rice plant treated with the chemical fertilizer control showed a protein content of 6.8%, which was even higher than the normal rice. The head rice ratio in the brown rice and the polished rice ended up to be lower in the crop treated with the liquid pig manure than that treated with the chemical fertilizer, Quality, the palatability value, was similar in both groups. The above result indicate that, the effect of liquid pig manure compost corresponds to the effect of chemical fertilizer, when each are scattered uniformly.

• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.87-93
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• 2003

Growth and mineral composition of young radish in soil amended with sewage sludge (ISS) with or without liming were investigated. Levels of EC, T-N, and micronutrients were increased in the ISS treatment (50 Mg/ha) compared to the NPK treatment but those of available P and exchangeable cations were decreased. Chlorosis was appear on the young radish leaf at the ISS treatment, but this phytotoxic symptom was corrected with lime amendment (3 Mg/ha). Yields of young radish leaf and root in the combined treatment of ISS and lime were increased about 29 and 48%, respectively, compared with those in the ISS treatment. Contents of P, K, Ca, and Mg in young radish were higher in the combined treatment to ISS and lime, whereas those contents in the ISS treatment were lower than those in the NPK treatment. Contents of Cu, Zn, and Ni in soil and young radish leaf were positively correlated with total N content in young radish leaf, while contents of P, K, Ca, and Mg were negatively correlated. Contents of Cu, Zn, and Ni in leaf were negatively correlated with yield of young radish. Contents of Cu and Zn in leaf corresponding with a 5% yield reduction of young radish were 22.4 and 349 mg/kg, respectively.

• Fire Science and Engineering
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• v.15 no.1
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• pp.34-40
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• 2001

Fire extinguishing efficiency of mixed gaseous agents were investigated by the cup-burner test and predicting by the model of flame extinguishing concentration. The binary mixed agents that tested were carbon dioxide/HFC-23, carbon dioxide/HCFC-22, carbon dioxide/HFC-227ea, carbon dioxide/HFC-125, carbon dioxide/FIC-13I1, Hexafluoropropylene/HFC-23 and ternary mixed agents were carbon dioxide/HFC-23/HFC-l34a, carbon dioxide/HFC-23/HFC-227ea, carbon dioxide/HFC-23/HFC-125. A model which contains the flame extinguishing concentration and composition of pure components predicted the flame extinguishing concentration of mixture well. This model was superior when each component of the mixture exhibit physical fire extinguishing performance.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.4
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• pp.215-218
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• 1982

The fertilizer efficiency of the compound fertilizers with different NPK Compositions were compared with that of simple fertilizers in the view of the yield differences of Jungweon Cheongyong Capsicum grossum of Hot pepper. The results were summarized as follows: 1. The yields of ripened red peppers of the compound fertilizer plot were higher than that of the simple fertilizer plot showing no statistical differences between the fertilizers. 2. No differences in the nutrient composition of the plant leaves were found between the treatments, thus the yield was not correlated with the nutrient composition. 3. In the soil where the compound fertilizers were used, the available phosphate content after the harvest increased but other nutrient contents were unchanged.