• 한국토양비료학회지
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• 제47권6호
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• pp.598-603
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• 2014

The level of nitrous oxide ($N_2O$), a long-lived greenhouse gas, in atmosphere has increased mainly due to anthropogenic sources, especially application of nitrogen fertilizers. Quantifying $N_2O$ emission in the agricultural field is essential to develop National inventories of greenhouse gases (GHGs) emission. The objective of this study was to develop emission factor to estimate direct $N_2O$ emission from agricultural field by measuring $N_2O$ emissions in the red pepper cultivating field from 2010 to 2012. Emission factor of $N_2O$ calculated from accumulated $N_2O$ emission, nitrogen fertilization rate, and background $N_2O$ emission was $0.0086{\pm}0.00043kg$ $N_2O-N\;kg^{-1}$ N resulted from three year experiment of the research sites. More extensive studies need to be conducted to develop $N_2O$ emission factors for other upland crops in the various regions of Korea because $N_2O$ emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices.

• 펄프종이기술
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• 제46권1호
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• pp.39-45
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• 2014

Various approaches have been tried to reduce the emission of carbon dioxide in paper industry. One of important approaches is to use PCC manufactured from emission gas as a filler. However, it was recognized that PCC is inferior to other fillers in the paper strength properties of view. Therefore, pretreatment of PCC with pulp powder was tried to mitigate the strength reduction of paper. Pretreatment of PCC with pulp powder improved the bulk(7.4~12.9%) and air permeability(24.8~42.98%), but there is no significant change in opacity. Tensile index, burst index and stiffness were decreased by the use of pretreated PCC with pulp powder. Anionic and cationic PAM were used as a additive for PCC pretreatment in order to improve strength properties. There was no significant change in bulk in all kinds of PAM used in this study. Most strength properties were improved by the pretreatment of PCC with the anionic and cationic PAM and pulp powder, although the opacity and stiffness were more or less decreased.

• 센서학회지
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• 제13권5호
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• pp.323-328
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• 2004

N-type semi-conducting oxides such as $SnO_{2}$, ZnO, and $ZrO_{2}$ have been known for the detecting materials of inflammable or toxic gases. Of those materials, $SnO_{2}$-based sensors are well known as high sensitive materials to detect toxic gases. And the sensitivity is improved if catalysts are added. Detecting toxic gases, especially DMMP (di-methyl-methyl-phosphonate) and DPGME (Dipropylene glycol methyl ether), was performed by a mixture of Tin oxide ($SnO_{2}$) and Zirconia ($ZrO_{2}$). The films consist of each three different mass% of Zr (from 1 mass% to 5 mass%), and they were tested by XRD, SEM, TEM, BET. Nano-structure, pore and particle size was controlled to verify the sensor's sensing mechanism. The sensors was evaluated at five different degrees (from $200^{\circ}C$ to $400^{\circ}C$) and three different concentrations (from 500 ppb to 1500 ppb). The sensors had good sensitivity of both simulants, and high selectivity of DMMP.

• Journal of Biosystems Engineering
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• 제5권1호
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• pp.33-42
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• 1980

This study was carried out to investigate the actual environmental paddy storage conditions in conventional Korean farm warehouses. The paddy storage conditions by the locations and sizes of warehouses were figured out. The effectiveness of the small insulated box for storing paddy was also examined. Observations were made at sixteen different warehouses located in Moonsan-Myeon, Jinyandg-gun, Gyungnam Province from July lst to September 28 th, the period which was considered to be the worst for storing grains. The results are as follows ; 1. the average temperatures of rough rice and air inside the warehouse were 0.9 and 0.7$^\circ$ higher than the outside air temperature. 2. The average relative humidity in warehouses was 1.5percent higher than that of the atomosphere. This fact resulted in the increased moisture content of grains. Therefore, the ventilation for equalizing the relative humidity of inside and outside of warehouses was required. 3. The dry matter of stored rough rice was decreased by 1.1 percent in average druing the observation period. In order to reduce the dry matter loss, application of new grain storing method ;hermetic storage or filling inert gas storage, was highly recommended. 4. Environmental conditions for storing rough rice in a warehouse located in a sloping site are, in general , better than those of a warehouse located in a flat site. But as far as the dry matter of rough rice was concerned, above situation is not always satisfactory. Because it is fairly frequent to observe the higher rate of moisture absorption by grains stored in a warehouse located in a sloping site. 5. Environmental conditions for storing rough rice in a large-scale warehouse were better than those in a small size warehouse. Therefore, it is advisible for farmers to store their grins in the large-scale warehouses commonly used by villagers. 6. It was undesirable to store rough in a insulated box.

• 유기물자원화
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• 제15권2호
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• pp.118-127
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• 2007

본 연구에서는 음식물류 폐기물의 탈리액을 이용하여 TS 농도를 변화시켜가면서 그 영향에 대하여 검토하였다. 산발효조와 메탄발효조가 연계되어진 $35^{\circ}C$의 중온소화조인 2상법 소화조(Dual digestion)에 의하여 TS 농도를 5%~10%까지 변화시켜 가면서 실험을 실시하였으며, 그 결과 원수의 투입 TS 농도가 7~8%일 때, 평균적인 제거효율 및 안정화를 나타냈으며 TS 농도 8%이후에는 대부분의 처리수 제거효율이 현저하게 감소하는 추세를 보였다. 반응조가 안정화한 단계에서 $0.3m^3/kg{\cdot}vs$이상의 가스발생량을 보였으며, 염분축적, pH상승의 등의 현상은 관찰되지 않았다. 본 연구를 통해서 음식물류 폐기물 탈리액의 혐기성소화에 있어서 TS 농도의 증가시 공정상에 처리 및 안정화에 미치는 영향이 있으나, TS 농도가 8%이상에서 그 영향이 큰 것으로 분석되었으며, 최종적으로 TS 농도를 8%이내에서 제어하면서 운전하는 것이 가장 효과적인 방법인 것으로 판단된다.

• 한국분말재료학회지
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• 제19권2호
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• pp.117-121
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• 2012

Tool steels serve a large range of applications including hot and cold workings of metals and injection mouldings of plastics or light alloys. The high speed steels (HSS) are specifically used as cutting tools and wear parts because it has high strength, wear resistance and hardness along with appreciable toughness and fatigue resistance. From the view of HSS microstructure, it can be described as metallic matrix composites formed by a ferrous with a dispersion of hard and wear resistant carbides. The experimental specimens were manufactured using the PIM with T42 powders (50~80 vol.%) and polymer (20~50 vol.%). The green parts were debinded in n-hexane solution at $60^{\circ}C$ for 8 hours and thermal debinded at an $N_2-H_2$ mixed gas atmosphere for 8 hours. Specimens were sintered in high vacuum ($10^{-5}$ Torr) and various temperatures.

• 한국안광학회지
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• 제8권2호
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• pp.85-89
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• 2003

구면 RGP 렌즈는 렌즈 후면과 각막 사이에 눈물이 일정한 두께를 형성하면서 뛰어난 난시교정효과를 나타낸다. 이러한 RGP 렌즈의 난시교정 효과를 체계적으로 연구하여 임상 구면 RGP 렌즈처방에 활용하고자 렌즈착용 전후의 전체난시량 변화 각막난시량의 변화, 잔여난시 변화를 비교, 분석하여 다음과 같은 결론을 얻었다. 1. 구면 RGP 렌즈의 교정 전 후 전체난시량이 2.00D 이하에서는 교정이 거의 모두 이루어졌으나, 전체 난시량이 2.50D 이상에서 미교정된 상태를 보였으며, 특히 3.00D 이상에서는 난시 교정효과가 급격히 감소되는 것으로 나타났다. 2. 구면 RGP 렌즈의 교정 전 후 각막난시량은 2.50D 이하에서 약도의 저교정 상태로 나타났으나, 3.00D이상에서는 전체난시와 마찬가지로 난시 교정효과가 감소되는 것으로 나타났다. 3. 구면 RGP 렌즈 처방시 잔여난시량은 그대로 발현하는 것이 아니고, 잔여난시 도수가 일정부분 감소하여 전체난시 상태로 나타났다.

• 한국농공학회논문집
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• 제59권4호
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• pp.53-64
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• 2017

The equations and emission factors for estimating national GHGs are developed based on IPCC guidelines. The GHGs on livestock sector has been calculated using methodologies following 1996 IPCC guideline in South Korea although 2006 IPCC guideline was announced in 2006. The purpose of this study is to understand the implications of guideline updates for national GHGs changes in the livestock sector and analyze the effect of regional major livestock characteristics using KOSTAT time series data (1990 ~ 2014). The results show a new guideline makes GHGs reduce in the livestock sector up to 11 % with subdivided emission factors and the livestock characteristics affect regional GHGs. Gyeonggi-do, the top emitter among 16 states, records 784 thousand tons $CO_2eq.$ and Daejeon has the highest potential (82 %) of GHGs reduction. Swine is the most contributor for regional GHGs except Seoul and Gwangju, but the share of GHGs for chickens is less than 12 % in spite of the largest livestock population (87 %).

• 한국토양비료학회지
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• 제49권6호
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• pp.720-730
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• 2016

Greenhouse-gas emission factors are widely used to estimate emissions arising from a defined unit of a specific activity. Such estimates are used both for international reporting to the United Nations Framework Convention on Climate Change (UNFCCC) and for myriad national and sub-national reporting purposes (for example, European Union Emissions Trading Scheme; EU ETS). As with the other so-called 'Kyoto protocol GHGs', the Intergovernmental Panel on Climate Change (IPCC) provides a methodology for national and sub-national estimation of $N_2O$ emissions, based on the sector from which the emissions arise. The objective of this study was to develop a integrated emission factor to estimate the direct $N_2O$ emission from an agricultural field cultivated with the red pepper, soy bean, spring cabbage, autumn cabbage and potato in 2010~2012. Emission factor of $N_2O$ calculated using accumulated $N_2O$ emission, N fertilization rate, and background $N_2O$ emission over three year experiment was $0.00596{\pm}0.001337kg$ $N_2O-N(N\;kg)^{-1}$. More extensive studies need to be conducted to develop $N_2O$ emission factors for other upland crops in the various regions of Korea because $N_2O$ emission is influenced by many factors including climate characteristics, soil properties, and agricultural practices.

• 대한임상독성학회지
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• 제10권1호
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• pp.33-36
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• 2012

Opioids are the one of the most commonly used drugs to control cancer pain all over the world. But, we should not overlook the potential risk of opioid intoxication because they have well-known detrimental side effects. The opioid intoxication can be diagnosed thorough various clinical manifestations. The altered mental status, respiratory depression, and miosis is very representative clinical features although these symptoms don't always appear together. Unfortunately the opioid-toxidrome can be varied. A 42 years old man came to our emergency room after taking about 900 mg morphine sulfate per oral. He was nearly alert and his respiration was normal. Even though his symptoms didn't deteriorated clinically, serial arterial blood gas analysis showed increase in PaCO2. So we decided to use intravenous naloxone. Soon, he was fully awaked and his pupils size was increased. After a continuous infusion of intravenous naloxone for 2 hours, PaCO2 decreased to normal range and his pupil size also returned to normal after 12 hours. Though the levels of serum amylase and lipase increased slightly, his pancreas was normal according to the abdominal computed tomography. He had nausea, vomit, and whole body itching after naloxone continuous infusion, but conservatively treated. We stopped the continuos infusion after 1 day because his laboratory results and physical examinations showed normal. As this case shows, it is very important to prescribe naloxone initially. If you suspect opioid intoxication, we recommend the initial use of naloxone even though a patient has atypical clinical features. In addition, we suggest intranasal administration of naloxone as safe and effective alternative and it's necessary to consider nalmefene that has a longer duration for opioid intoxication.