• Journal of Korean Society of Forest Science
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• v.79 no.4
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• pp.419-423
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• 1990

This study was carried out to investigate the cause of pith-damaged wood formation, the state of growth, and difference of chemical composition of Japanese Larix(L. leptolepis Gorden). 1. Larix grew normaly to 10 years, and the volume increment was 32.4%. But it was gradually decreased to 19.4% from 11 to 13 years that the heartwood damage was occurred. Therefore, the volume increment was decreased 13%. The decayed wood was formed from fire wound portion of bark by forest fire. The volume loss from pith-dagmaged wood occurred by forest fire was more than 20%. 2. On the ash content, heartwood(0.05%) and pith-damaged wood(0.08%) was lower than sapwood(0.29%). The difference of extractive contents are considered the reason. It is considered that this ash content difference is depend upon the extractive contents among sap, heart and decayed wood parts. Holocellulose contents were from 54.3% to 59.3% and there were no difference among heartwood, pith-damaged wood, and sapwood, On the pentosan contents, heartwood(6.3%) and pith-damaged wood(6.6%) were higher than sapwood. Lignin contents of pith-damaged wood was tower than heartwood (34.4%). This seems to weaken all kinds of wood strength.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1421-1432
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• 2018

Water soluble oil was obtained from the pyrolysis of coconut waste as a biomass at $600^{\circ}C$. It was studied that the combustion characteristics of bio-emulsion fuel by mixing and emulsifying 15~20% of water soluble oil which obtained from pyrolysis of coconut waste as a biomass and MDO(marine diesel oil) as a marine fuel. Engine dynamometer was used for detecting emissions, temperature, and power. The temperature of combustion chamber was decreased because the moisture in bio-emulsion fuel deprived of heat of evaporation in combustion chamber. While combustion, micro-explosion took place in the combustion chamber by water in the bio-emulsion fuel, MDO fuel scattered to micro particles and it caused to smoke reduction. The temperature reduction of combustion chamber by using bio-emulsion fuel reduced the NOx emission. The increasing of bio-oil content caused increasing water content in bio-emulsion fuel so total calorific value was reduced. So the characteristics of power was decreased in proportion to using the increasing amount of bio-emulsion fuel. Heavy oil as a marine fuel exhausts a lot of smoke and NOx. We expect that we can reduce the exhaust gas of marine engine such as smoke and NOx by using of bio-emulsion fuel as a marine fuel.

• Journal of Korean Society on Water Environment
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• v.30 no.5
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• pp.469-476
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• 2014

The focus of this study was to observe the growth of Chlorella sp., Nannochloris sp., and Botryococcus braunii under mixotrophic conditions (i.e., added glycerol) with the aim of increasing the growth of biomass and algae oil content. A significant growth of biomass was obtained when grown in glycerol rich environment comparing to autotrophic conditions. 5 g/L glycerol yielded the highest biomass concentration for these strains. Mixotrophic conditions improved both the growth of the microalgae and the accumulation of triacylglycerols (TAGs). The maximum amount of TAG in Botryococcus braunii was reached in the growth medium with 10 g/L glycerol and Chlorella sp., Nannochloris sp. with 2 g/L glycerol. The content of saturated fatty acids of Chlorella sp., Nannochloris sp., and Botryococcus braunii was found to be 34.94, 14.23 and 13.39%, and the amount of unsaturated fatty acids was 65.06, 85.78 and 86.61% of total fatty acids, respectively. The fatty acid profiles of the oil for the culture possibility met the necessary requirements and are, therefore, promising resource for biofuel production.

• The Journal of the Korea Contents Association
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• v.15 no.1
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• pp.324-330
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• 2015

When diagnostic ultrasounds are used, an ultrasonic transmission media is used to effectively transmit the ultrasonic energy. Types of ingredients of polymer hydro gel, emulsion, and oil gel were compared with commercialized products by measuring characteristics of ultrasonic transmission media such as skin lubricity, skin moisturizing, and dryness speed which were contained in each different media. The mean friction coefficient measured to investigate skin lubricity showed high in the agent containing a large amount of oil, whereas the mean friction coefficient of the low viscosity emulsion did not show a significant difference with that of the polymer hydro gel. The moisture evaporation measured to investigate the dryness speed of the agent showed highest in polymer hydro gel. This showed that the larger amount of oil it had, the less moisture evaporation occurred. For skin moisture measured to investigate moisturizing characteristics of skin, low viscosity emulsion showed high in moisture content, whereas it showed slowest reduction in moisture content. As a type of emulsion appropriately containing water and oil is superior in skin moisturizing and skin tenderness, it is expected to serve as a dosage form of new ultrasonic transmission media.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.4
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• pp.29-35
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• 2009

Pyrolysis is recently used as one of alternative methods of animal waste treatment. In this study bio-oil was produced at $550^{\circ}C$ in an auger reactor through pyrolysis process. Two pig waste mixtures were used, pig feces mixed with rice husks and pig feces mixed with sawdust. The main compositions of hemicellulose, lignin, cellulose, protein, and fat were analyzed chemically. Based on the main composition results obtained, the contents of holocellulose (the sum of hemicellulose and cellulose) and lignin had a significant positive effect on bio-oil production, and there was a significant negative effect of ash content on bio-oil yield. The interactions between the different feedstocks were evaluated, and it was concluded that the interaction between pig feces and rice husks was minimal, whereas the interaction between pig feces and sawdust was significant.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.299-299
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• 2023

토양수분(soil moisture)은 수문인자의 하나로서 토양 내에 함유된 물의 양을 의미하며, 그 총량은 미미하지만 대기와 지표면 사이에서 일어나는 복잡한 물순환과 에너지 교환을 이해하는데 있어 필수적이다. 현재 국내에서는 「수자원의 조사·계획 및 관리에 관한 법률」(이하 수자원법)에 근거해 토양수분량 관측이 이루어지고 있으며, 수자원 분야의 한국수자원조사기술원 외에도 농업, 임업 분야에서도 다양한 기관에서 지상관측소를 구축해 토양수분량을 측정하고 있다. 국내 지상관측소에서는 주로 지점규모(point scale)로 토양수분량을 관측하는 장비가 사용되고 있으며, 유전율식 장비인 TDR(Time Domain Reflectometry), FDR(Frequency Domain Reflectometry)이나 토양수분장력을 측정하는 장력계(Tensiometer)가 널리 쓰이고 있다. 수자원분야에서는 토양 내 수분의 양을 직관적으로 확인할 수 있는 유전율식 장비가 대중적으로 사용되고 있으며, 최근에는 우주선(Cosmic-Ray)으로부터 발생하는 고속중성자(Fast Neutron)를 통해 중규모 면단위(field scale) 토양수분량을 관측하는 장비인 CRNP(Cosmic-Ray Neutron Probe)에 대한 연구도 활발히 진행되고 있다. 이러한 장비는 주로 야외에 설치해 운영하고 있기 때문에 장비 훼손이나 전원공급의 어려움으로 결측이나 오측이 발생할 수 있다. 토양수분량 시계열자료의 결측이나 오측이 일반적인 감쇄기에 발생했다면 선형보간법으로도 간단히 보간할 수 있지만, 강우에 의한 상승기에 발생했다면 해당 강우사상에서의 토양수분량의 상한치를 알기 어려워 결측보간에 어려움이 있다. 본 연구에서는 토양수분량 시계열자료의 강우기간 결측을 보간하는 방법으로 누적분포함수 역변환 샘플링방법을 선택하였다. 연구에는 음성군(차곡리) 토양수분량 관측소 2021년 자료가 사용되었으며, 관측소 56개 지점 중 임의의 지점에 결측구간을 생성한 뒤 해당 지점과의 상관계수가 높은 지점의 누적분포함수를 이용해 역변환 샘플링 방식으로 임의 지점의 결측을 보간하고 그 결과를 기존값과 비교해 보간 방법의 정확도를 평가하였다.

• Journal of Nutrition and Health
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• v.16 no.3
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• pp.185-192
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• 1983

한국인과 한국산 가축의 selenium 영양상태를 파악하기 위하여 남한의 selenium 분포조사를 실시한 결과 전국 45개 지역 토양중 selenium 함량은 0.03 내지 0.24 ppm이였으며 중앙 동북 고산지대는 0.14-0.24 ppm으로 높았고 서해안 그리고 남해안은 0.03-0.06 ppm으로 비교적 낮았다. 전국 42개 지역에서 채취한 목초 (억새, 크로바 )는 0.036 ppm (0.02-0.13ppm )을 함유하고 있으며 콩, 보리, 쌀은 0.047, 0.033 그리고 0.033 ppm selenium을 각각 함유하고 있었다. 전국 23개 도시에 거주하는 204명의 사람에서 채취한 혈액에는 평균 $0.16\;{\pm}\;0.06{\mu}g/m1$ $(0.05-0.35{\mu}g/ml)$ selenium 함량을 갖었고 glutathione peroxidase 활성도는 평균 $13.0\;{\pm}\;1.7\;EU/mg$ homoglobin이었다. 남한에서 생산되는 곡류와 채소류에는 0.02 내지 0.04 ppm의 selenium을 함유하고 육류인 쇠고기, 돼지고기에는 $0.11\;{\pm}\;0.05$와 $0.14\;{\pm}\;0.03\;ppm$을 그리고 참치, 조기, 숭어, 마른멸치등에는 $0.50\;{\pm}\;0.02,\;0.42\;{\pm}\;0.09,\;0.20\;{\pm}\;0.02$ 그리고 $0.55\;{\pm}\;0.04\;ppm$ selenium을 각각 함유하고 있었다. 국민 1인당 하루 selenium 섭취량은 $42.3\;{\mu}g$이며 이중 71 %는 주로 곡류와 채소에서 충당하고 있다.

• Proceedings of the KAIS Fall Conference
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• 2010.11b
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• pp.882-884
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• 2010

본 연구는 피부미용전문가에 의한 관리 후, 홈케어 유무에 따른 건조피부의 개선 효과를 알아보고자 하였다. 건조피부로 평가된 10명을 대상으로, 한족 팔에는 마사지와 홈케어를 적용하고, 다른 쪽 팔에는 단지 마사지만을 적용하였다. 마사지는 호호바오일에 라벤더정유를 혼합하여, 10분간의 마사지를 주 2회로 총 4주 동안 실시하였고, 홈케어로는 마사지에서 사용한 시료를 집에서 매일 바르도록 하였다. 실험 결과 마사지와 홈케어를 적용한 그룹이 마사지만을 한 그룹보다 유분과 수분의 함유량이 증가하였다. 특히, 마사지와 홈케어를 한 그룹에서 마사지의 횟수가 증가 될수록 피부에서의 유 수분은 증가하는 것을 알 수 있었다. 따라서 전문가에 의한 관리효과를 유지하고, 더 효과적으로 건조증상를 개선시키기 위해서는 무엇보다도 홈케어의 중요성이 강조되어야 한다.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.694-699
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• 2008

Considering the severe regulation associated with sludge treatment such as direct landfill and ocean dumping, there is no doubt in that an advanced study for the proper treatment of sludge is urgently needed in near feature. As one of viable method for sludge treatment, fry-drying of sludge by waste oil has been investigated in this study. The fundamental mechanism of this drying method lies in the phenomenon of rapid moisture escape in the sludge pore toward oil media. This is caused by the severe pressure gradient formed by the rapid oil heating between sludge and oil. As part of research effort of fry-drying using waste oil, a series of basic study has been made experimentally to obtain typical drying curves as function of important parameters such as drying temperature, drying time, oil type and geometrical shape of sludge formed. Based on this study, a number of useful conclusion can be drawn as following. The fry-drying method by oil immersion was found quite effective in the removal efficiency of sludge moisture, in general, the moisture content decreases significantly after 10 minutes and the whole moisture content was less than 5% after 14 minutes regardless of the drying temperature. The increase of oil temperature up to 140$^{\circ}C$ favors significantly for the removal of moisture but there was no visible difference above 140$^{\circ}C$. As expected, the decrease of diameter in sludge was efficient in drying due to the increased surface area per unit volume. Further, the effect of oil property by the change of oil type was noted. To be specific, for the case of engine oil the efficiency was found to be remarkably delayed in moisture evaporation compared with that of vegetable oil due to the increased viscosity of engine oil. It produced a result of increasing the evaporation of moisture largely relatively high in the drying temperature over 140$^{\circ}C$ compared with the drying temperature 120$^{\circ}C$ drying temperature as the drying time passed. Accordingly, the drying temperature is considered desirable as keeping over 140$^{\circ}C$ regardless of a sort of used oil.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.369-374
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• 2015

In this study, by combining a unique purpose and additional aspects of ultrasonic transmission media, a development potential on a new ultrasonic transmission media was sought. The rheological characteristics and the manufacturing cost for each manufactured formulation were compared and analysed with ready-made. An ultrasonic transmission media is to have different functional characteristics according to the following formulation, it was the best in rheological value, low viscosity emulsion with the oil gel. Polymer hydro gel is can be manufactured at low cost compared to other formulations. Emulsion which shows a sharp viscosity difference according to the components of oil and water had a big difference in manufacturing cost. This study can be utilized as the fundamental data on the ultrasound transmission media equipped with expertise in various areas of ultrasound.