• Childhood Kidney Diseases
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• v.13 no.1
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• pp.21-25
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• 2009

Last year, an epidemic of infantile urinary stone disease developed in China. Investigation revealed that melamine-tainted diary product caused urinary stone in these infants. Young infants were susceptible to the melamine toxicity and dehydration or other stone-prone factors aggravated the toxicity. Melamine-related urinary stones were small, multiple, and mainly composed of uric acid, thus conservative treatment of hydration and urine alkalinization worked well in majority of the patients.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.725-728
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• 2007

본 연구에서는 액상폐기물의 가스화를 통하여 합성가스를 생산하는 공정기술에 관하여 고찰 하였다. 폐기물의 가스화공정기술은 공기, 산소등과 액상폐기물을 고온하에서 가스화반응시켜 폐기물중에 포함된 가연성성분은 CO, $H_2$가 주성분인 합성가스로 전환시키고, 폐기물내에 포함된 무기물은 용융시켜 slag의 형태로 배출시키는 기술이다. 폐기물투입장치, 가스화기 및 용융로, 슬랙배출장치, 합성가스 정제장치, 그리고 수처리장치등로 구성된 Bench급의 가스화용용시스템을 구성하고, 수분 16%, 발열량 4375kcal/kg의 액상폐기물을 가스화 실험한 결과 CO가 $31{\sim}35%$, $H_2$가 $28{\sim}36%$ 포함된 합성가스를 얻을 수 있었고, 합성가스의 발열량은 $1735{\sim}2160kcal/kg$로 나타났다. 또한 가스의 세정에 사용된 세정폐수의 분석과 무기물의 용융을 통하여 발생한 용용슬랙의 용출실험을 통해서 합성가스 생성과정에서의 이차오염 물질은 환경규제치 이하로 발생함을 확인할 수 있었다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.140-143
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• 2001

The packed column experiments were conducted with commercial Jumunjin sand(SOM content : 0.01 %) and a field soil(SOM content : 0.08 %) in order to understand the effects of water content and soil organic matter(SOM) on the transport of gaseous ozone in unsaturated soil contaminated with phenanthrene. Water content and SOM content were artificially controlled. As water content increased, earlier breakthrough was observed in the beginning of BTC of ozone, because direct contact of gaseous ozone with SOM and phenanthrene was prevented by water film formed between soil particles and gaseous ozone. The total removal of phenanthrene in Jumunjin sand was not affected by water content which was more than 99% at different water content(4.4, 8, 17.3%). However, the removal in field soil at water content 6.5 % and 20 % was 98% and 80 %.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.04a
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• pp.165-174
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• 2000

새로운 에너지원으로 개발된 오리멀젼의 국내 활용에 관한 기술적인 특성을 파악하기 위하여 연료 특성과 연소에 대한 실험적인 연구를 수행하였다. 연료저장을 위한 최적온도는 6$0^{\circ}C$이었으며 온도가 낮으면 점화특성이 불량하고 너무 상승하는 경우에는 계면분리 현상이 보였다. 연소를 위해 필요한 연소실온도는 $600^{\circ}C$ 이상이 요구되었고 수분의 비등폭발에 의해 2차 연소가 특징적으로 관찰되었다. 오리멀젼 연소시 배기가스중 오염물질 농도는 과잉공기비에 SO$_2$ 가 1700-2200ppm , NOx 100-150ppm 으로 측정되었다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.6
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• pp.524-531
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• 2001

The temperature and humidity distribution in a dry room are studied numerically by using standard$\kappa-\varepsilon$ turbulence model. In order to evaluate effective heat and moisture ventilation characteristics inside the room, the heat removal capacity and moisture exhaust efficiency are introduced. An effective ventilation control is analyzed by evaluating quantitatively temperature and humidity distributions. It was found that the mean absolute humidity inside the room was almost constant with approximately 0.1905g/kg air regardless of the models and the heat generation rates. This was believed that the moisture generation by workers was relatively small. 40% improvement of the critical decay time was achieved, through the modifications of design variables.

• KOREAN POULTRY JOURNAL
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• v.37 no.10 s.432
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• pp.77-79
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• 2005

최근 우리나라도 전업축산농가의 양계사육 규모가 확대되면서 이에 수반되는 양계장 주변의 악취, 수질 오염 등의 환경문제가 심각하게 대두되고 있다. 축산경영의 건전한 발전을 위해서도 이 문제의 해결은 시급한 과제이며 특히 경영주의 환경의식과 의지가 문제해결의 시발점임을 인식해야 한다. 물론 양계장에서 환경친화적으로 계분을 처리한다는 것은 그리 용이한 일은 아니다. 특히 산란계 사육농가의 계분은 끈적끈적한 오물감과 냄새로 취급하기가 쉽지 않다. 그 원인은 수분 함유량이 높고 역분해성 유기물(분해 용이한 유기물)이 부패되면서 악취와 해충을 발생시키기 때문이다. 현재 계분처리방법은 여러 가지가 있으나 첫째, 지구환경에 친화적인 처리방법으로는 유기성 폐기물인 계분의 재활용에 있다고 생각한다. 현재와 같이 지구환경의 밸런스가 망가지는 상황은 사람들이 다량의 소비만 일삼고 환경 리싸이클에 관심이 덜한데 있다고 본다. 자원 순환형 사회에서 계분의 퇴비화로 가축분뇨를 유통 · 활용하는 일은 유기성 자원의 리사이클에 공헌하는 의미가 크다고 본다. 또한 우리나라의 축산업이 환경 보전형 농업을 실현하는데 보탬이 되는 양질의 퇴비를 대량 생산하여 경작농가에 공급, 유기질 농산물 생산에 많이 기여하길 바란다.

• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.23-30
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• 2006

Emulsified Asphalt Mixture(EAM) is more environmentally-friendly and cost-effective than typical Hot Mix Asphalt (HMA) because EAM does not produce carcinogenic substances, e.g., naphtha, kerosene, during the both of manufacturing and roadway construction process. Also, it does not require heating the aggregates and asphalt binder. However, EAM has some disadvantages. Generally EAM has a less load bearing capacity and more moisture susceptibility than conventional HMA. The study evaluated a Fiber modified EAM (FEAM) to increase load bearing capacity and to decrease moisture susceptibility of EAM. Modified Marshall mix design was developed to find Optimum Emulsion Contents (OEC), Optimum Water Contents (OWC), and Optimum Fiber Contents (OFC). A series of test were performed on the fabricated specimen with OBC, OWC, and OFC. Tests include Marshall Stability, Indirect Tensile Strength, and Resilient modulus test. Comparison analyses were performed among EAM, Fiber modified EAM (FEAM), and typical HMA to verify the applicability of EAM and FEAM in the field. Test results indicated that both of EAM and FEAM have an enough capability to resist medium traffic volume based on the Marshall mix design criteria. Also the study found that fiber modification is effective to increase the load bearing capacity and moisture damage resistance of EAM.

• Food Science and Preservation
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• v.11 no.2
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• pp.189-194
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• 2004

This experiment was carried out to compare the quality of semi-dried persimmon according to various drying methods and ripeness degree of persimmons. Most of persimmons were dried naturally there were much opportunities of contamination by impurities, microorganism and discoloration. There were need for developing various drying methods and knowing proper mature degree of persimmons in order to enhance the quality of semi-dried persimmons. Drying time of semi-dried persimmons by hot-air, far infrared ray and dehumid drying could be shorten approximately 11∼12 days, comparing with natural drying. And the loss ratio of natural drying and artifical drying were 7.0% and 0.0%. The moisture content of natural drying and dehumid drying were simillar and the hardness were very low in comparing other drying methods. Average pannel scores in semi-dried persimmons after drying showed that dehumid drying and natural drying were excellent in total prefernce ; 3.9 and 3.4, respectively. Unriped persimmons showed lower moisture content, color values and higher hardness than riped and overriped persimmons. The total preference of riped and overriped fruit were superior than unriped fruit.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.957-961
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• 2005

Spoilage yeast was isolated from spoiled rice-syrup and identified by Microbial Identification system (MIDI) as Zygosaccharomyces bailii based on composition of fatty acids exhibiting carbon skeleton of 16:0, 16.1 $({\Delta}cis\;7)$, 18:2 $({\Delta}cis\;9)$, 18:1 $({\Delta}cis\;9)$, and 18:1. Increase in sugar content $(1^{\circ}brix)$ resulted in decreased moisture concentration (1%), and water activity decreased from 0.72 to 0,63 when sugar concentration increased from 77 to $83^{\circ}brix$. Yeast showed very slow growth during three weeks post-inoculation in rice-syrup at 17 and $79^{\circ}brix$, and maximal level of Z. bailii was found at 6 and 10 weeks storage at 15 and $25^{\circ}C$, respectively. At over $81^{\circ}brix$ its growth slowly decreased at beginning of storage, indicating rice-syrup could be preserved safely at above $81^{\circ}brix$ sugar content without Z. bailii contamination.

• Korean Journal of Environmental Agriculture
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• v.13 no.2
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• pp.223-230
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• 1994

A practical study on a drying and fermentation system equipped with a stirring machine operated mechanically, of pig manure was conducted to prove the efficiency of and practicability to an ordinary pig farm. The type of the drying bed was a round-shaped (r=3m) concrete structure and the stirring machine was adopted to stir and transfer dried pig manure to the fermentation tank. The dried pig manure was put into a fermentation tank ($V=18m^3$), which was aerated from pipe lines installed at the bottom. While water content of pig manure passing through a drying bed was remarkably reduced than before drying, the drying efficiency of this system decreased in winter. However, the temperature of pig manure piled up in the fermentation room in winter reached over $60^{\circ}C$ and excess water of pig manure was removed during the fermentation process. The reduction rate of water content of pig manure, to which dried pig manure was added as bulking material on the drying bed, was 52.1%, but when dried without bulking material it was only 19.7%. Although the content of $P_2O_5$ of dried pig manure was slightly higher than that of fresh pig manure, progressive changes in chemical composition between fresh and dried pig manure made no great difference. Among the contents of minerals of fresh and dried pig manure, CaO was the highest and the rest were in the decreasing order of $K_2O$, MgO, and $Na_2O$. Population density of E. coli and Streptococci of dried pig manure was reduced by 142 and 236 times that of fresh pig manure, respectively. The installation cost of this drying and fermentation system was 4,185,630 won (approximately 5,232 US $) and operating cost per year was 190,000 won (237.5US $) on the basis of self-labor condition.