• Journal of Korean Society of Environmental Engineers
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• v.31 no.8
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• pp.679-689
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• 2009

Light olefins are very important hydrocarbons widely used as the raw materials of the most petrochemicals including plastics and medicines. In addition, the nation's olefin production capacity is regarded as one of the key indicators to predict the nation's economic scale and growth. Steam cracking of naphtha (or called "NCC (Naphtha Cracking Center) technology"), the traditional process to produce light olefins, is one of the most consuming energy processes among the chemical industries. Therefore, this process causes tremendous $CO_2$ emission. To reduce the energy consumption and $CO_2$ emission from NCC process, the present paper, firstly, investigates and analyses some alternative technologies which can be potentially substituted for traditional process. Secondly, applying the alternative technologies to NCC process, their effects such as energy savings, $CO_2$ emission reduction and CER (Certified Emission Reduction) were estimated. It is found that the advanced NCC process can reduce approximately 35% of SEC (Specific Energy Consumption) of traditional NCC process. This effect can lead to the reduction of 3.3 million tons of $CO_2$ and the acquisition of the 128 billion won of CER per year. Catalytic cracking of naphtha technology, which is other alternative processes, can save up to approximately 40% of SEC of traditional NCC process. This value equates to the 3.8 million tons of $CO_2$ mitigation and 147 billion won of CER per year.

• Applied Biological Chemistry
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• v.20 no.2
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• pp.236-241
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• 1977

Analytical method of carbofuran (2,3-dihydro-2, 2-dimethyl-7-benzofuranyl methyl carbamate) residues and its persistence in rice seeds, rice seedlings, rice plants and soils were studied by gas-liquid chromatographic analysis using electron capture detector. 1. The effective column material for clean-up is Florisil (5% $H_2O$)+Alumina (4% $H_2O$)+absorbent mixture with rinsing the first 300l of eluants to remove impurities in the column materials. 2. The method of applying an gelatin encapsulated carbofuran to the root zone of rice plant is the longest persistence in its residues. 3. By seed treatment, no carbofuran residues were detected in rice seeds and seedlings. 4. The amounts of carbofuran residues in rice seedlings is in proportion to the soaking time of rice seedlings in carbofuran solution rather than the concentration of the chemical. 5. Applying carbofuran by root zone has the higher and the loger residual effect than broadcast. 6. Persistence of carbofuran in the high clay content soil is longer than in the low clay content soil. 7. No carbofuran residue was detected in rough rice at havesting time.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.2
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• pp.171-178
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• 2003

연구 목적: Microarray data에 의해 밝혀진 생쥐자궁에서의 Id 유전자의 hormonal effect와 implantation process 동안의 관계를 조사하고자 실험을 수행하였다. 연구재료 및 방법: 난소절제한 생쥐에 estrogen을 주사하고 6시간, 12시간이 지난 후 자궁을 적출하여 두 가지 방법으로 sample을 준비하였다. 먼저 자궁전체의 RNA를 추출하여 실험하거나 laser capture microdissection (LCM) 방법으로 자궁내막상피세포, 자궁기질세포, 자궁근육층으로 분리하여 RNA를 추출하고 semi-quantative RT-PCR을 수행하여 Id 유전자의 발현을 조사하였다. 임신 4.5일째 생쥐에 Chicago blue dye를 주사하여 착상부위와 비착상부위를 분리하고 RNA를 추출하여 Id 유전자의 발현을 semiquantitative RT-PCR 방법으로 실험하였다. 결 과: Estrogen을 처리한 난소절제된 생쥐 자궁에서의 cDNA microarray 자료에서 Id-1 mRNA는 점진적으로 두 배 이상 증가하였고 Id-2 mNRA는 반대로 시간이 지날수록 두 배 이상 감소하였다. Microarray 자료를 재확인하기 위해 semi-quantitative RT-PCR을 이용하여 실험하였고, 그 결과 Id-1 유전자는 estrogen 처리 6시간까지는 큰 변화가 없었으나 12시간에서는 4배 이상의 높은 발현을 보였으며, Id-2 mRNA의 발현은 estrogen 처리 6시간과 12시간 모두에서 대조군에 비해 4배 가량 감소하였다. 이 실험군을 LCM을 이용하여 자궁내막상피세포, 자궁기질세포, 자궁근육층을 각각 분리하여 실험한 결과 estrogen 처리군에서 Id-1의 발현은 자궁내막상피세포에서만 높은 발현을 보였으며, estrogen 처리 6시간과 12시간에는 큰 차이를 보이지 않았다. 그러나, Id-2 mRNA는 자궁내막상피세포에서 estrogen 처리 6, 12시간 모두에서 높은 발현을 보였고, 근육세포층에서는 estrogen 처리 6시간에서는 변화가 거의 없었으나 12시간에는 현저하게 증가하였다. 단, 자궁기질세포에서는 대조군에 비해 estrogen 6, 12시간에서 Id-2 mRNA의 발현이 감소하였다. 임신한 생쥐 자궁의 착상부위에서는 Id-1 mNRA의 발현은 비착상부 위보다 월등하게 높은 증가를 보였다. 결 론: 난소절제 생쥐를 이용한 실험에서 Id-1, -3는 estrogen에 의해 발현이 증가하고, Id-2는 발현이 감소하였다. LCM을 이용한 실험에서는 Id-2는 이와는 달리 부위별 발현양상은 다르게 나타났지만 이는 넓은 부위를 차지하는 자궁기질에서의 발현감소가 전체적인 Id-2의 발현양상으로 나타난 것으로 추측된다. 착상부위에서의 Id의 발현은 Id-1만이 유일하게 월등한 증가를 보였다. 위의 결과를 종합해 볼 때 생쥐 자궁에서 Id 유전자는 estrogen에 의해 조절되며 직, 간접적으로 착상시기에 다양한 작용을 할 것으로 사료된다.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.1167-1172
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• 2009

The Pneumatic Reduction and VCUG (Voiding Cystourethrography) are commonly used in the paediatric age group. The procedures had a particularly long fluroscopic screening time, despite a successful outcome for paediatric patients. Pneumatic Reduction and VCUG almost invariably requires fluoroscopic guidance which does confer a radiation dose. This article contains suggestions on how the radiation dose to paediatric patients from Pneumatic Reduction and VCUG can be made "as low as reasonably achievable" (ALARA). The aim of our study was eliminated in spot image applying the FluoroGrab, which has function of capturing an image of interest area from the picturing while fluoroscopic procedures. FluoroGrab has clinical value equivalent to the spot image, and is applied to the most recent fluoroscopic procedures. The radiologist and the radiographers should consider new option for decreasing the radiation exposure delivered to paediatric patients by making equipment modifications to the fluoroscopy to optimize radiation exposure reduction techniques. Thus, we propose the FluoroGrab instead of spot exposure for the reduction of patient exposure dose in paediatric, and try to confirm the effect of the mitigating amount of radiation exposure to paediatric patients when pneumatic reduction and VCUG. Fluorograb is the safe and useful method that shows the equivalent level of accuracy to spot exposure, and to minimize the radiation load to paediatric patients are to be the substitute for the spot exposure for Pneumatic Reduction and VCUG.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.15-15
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• 2011

As you know, boron compounds, borax ($Na_2B_4O_5(OH)_4{\cdot}8H_2O$) etc. were known thousands of years ago. As for natural boron, it has two naturally occurring and stable isotopes, boron 11 ($^{11}B$) and boron 10 ($^{10}B$). The neutron absorption $^{10}B$ is included about 19~20% with 80~81% $^{11}B$. Boron is similar to carbon in its capability to form stable covalently bonded molecular networks. The mass difference results in a wide range of ${\beta}$ values between the $^{11}B$ and $^{10}B$. The $^{10}B$ isotope, stable with 5 neutrons is excellent at capturing thermal neutrons. For example, it is possible to decrease a thermal neutron required for the nuclear reaction of uranium 235 ($^{235}U$). If $^{10}B$ absorbs a neutron ($^1n$), it will change to $^7Li+^1{\alpha}$ (${\alpha}$ ray, like $^4He$) with prompt ${\gamma}$ ray from $^{11}B$ $^{11}B$ (equation 1). $$^{10}B+^1n\;{\rightarrow}\;^{11}B\;{\rightarrow}\; prompt \;{\gamma}\;ray (478 keV), \;^7Li+4{\alpha}\;(4He)\;\;\;\;{\cdots}\; (1)$$ If about 1% boron is added to stainless steel, it is known that a neutron shielding effect will be 3 times the boron free steel. Enriched boron or $^{10}B$ is used in both radiation shielding and in boron neutron capture therapy. Then, $^{10}B$ is used for reactivity control and in emergency shutdown systems in nuclear reactors. Furthermore, boron carbide, $B_4C$, is used as the charge of a nuclear fission reaction control rod material and neutron cover material for nuclear reactors. The $B_4C$ powder of natural B composition is used as a charge of a control material of a boiling water reactor (BWR) which occupies commercial power reactors in nuclear power generation. The $B_4C$ sintered body which adjusted $^{10}B$ concentration is used as a charge of a control material of the fast breeder reactor (FBR) currently developed aiming at establishment of a nuclear fuel cycle. In this study for new boron compound, silicon boride ceramics for capturing thermal neutrons, preparation and characterization of both silicon tetraboride ($SiB_4$) and silicon hexaboride ($SiB_6$) and ceramics produced by sintering were investigated in order to determine the suitability of this material for nuclear power generation. The relative density increased with increasing sintering temperature. With a sintering temperature of 1,923 K, a sintered body having a relative density of more than 99% was obtained. The Vickers hardness increased with increasing sintering temperature. The best result was a Vickers hardness of 28 GPa for the $SiB_6$ sintered at 1,923K for 1 h. The high temperature Vickers hardness of the $SiB_6$ sintered body changed from 28 to 12 GPa in the temperature range of room temperature to 1,273 K. The thermal conductivity of the SiB6 sintered body changed from 9.1 to 2.4 W/mK in the range of room temperature to 1,273 K.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.2
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• pp.13-20
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• 2020

One of the major issues surrounding big data is the availability of massive time-based or telemetry data. Now, the appearance of low cost capture and storage devices has become possible to get very detailed time data to be used for further analysis. Thus, we can use these time data to get more knowledge about the underlying system or to predict future events with higher accuracy. In particular, it is very important to define custom tailored contract offers for many households and businesses having smart meter records and predict the future electricity usage to protect the electricity companies from power shortage or power surplus. It is required to identify a few groups with common electricity behavior to make it worth the creation of customized contract offers. This study suggests big data transformation as a side effect and clustering technique to understand the electricity usage pattern by using the open data related to smart meter and KNIME which is an open source platform for data analytics, providing a user-friendly graphical workbench for the entire analysis process. While the big data components are not open source, they are also available for a trial if required. After importing, cleaning and transforming the smart meter big data, it is possible to interpret each meter data in terms of electricity usage behavior through a dynamic time warping method.

• Economic and Environmental Geology
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• v.40 no.1 s.182
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• pp.129-140
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• 2007

CFC(CFC-12, CFC-11 and CFC-113) analytical system for air and water was constructed using a customized purge and trap extraction device and a gas chromatograph with an electron capture detector. Sampling methods of air and water for CFCs were also established. The analytical system was experimentally optimized to result in reproducibilities of triplicates less than 2% for current air samples and less than 5% for groundwater samples with CFC-12 concentration of 160 to 180 pg/kg, and verified with respect to the CFC system in USGS, which showed analytical results were in agreement within 10%. CFCs in air were monitored at three sites over 19-month period in the central part of South Korea, and the result indicates no significant local sources of CFCs in those areas. For groundwater in Jeju Island, CFCs were measured over a year with a two-month interval. The time-series data showed seasonal fluctuations which could be interpreted by the effect of recharge pulse derived from large amount of rainfall during monsoon period with a few month delay, which indicates high permeability of basaltic rocks in Jeju Island.

• Journal of Korean Society of Forest Science
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• v.97 no.1
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• pp.30-34
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• 2008

This study was conducted to develop environmental techniques to reduce chestnut insect pests. The study sites were selected in intensive chestnut orchards of Jinju city, Gyeongnam province. In early and middleripening cultivars of chestnut tree, the damage of chestnut fruits by Dichocrocis punctiferalis was significantly lower in wromstop than other treatment such as Capture-machine, Nemacatch and Naphthalene (p<0.05), while there was no significant difference among treatments in late-ripening cultivars. The control effect of D. punctiferalis showed the highest in wormstop treanment with 90.68% and 80.58% in early and middle-ripening cultivars. The control effects for Curculio sikkimensis in late-ripening cultivars of chestnut tree was 80.58% in Nemacatch and 77.90% in Wormstop treatment.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.6-14
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• 2016

BACKGROUND: Residual organochlorine pesticides (OCPs) are chemical substances that persist in the environment, bioaccumulate through the food web, and pose a risk of causing adverse effect to human health and the environment. They were designated as persistent organic pollutants (POPs) by Stockholm Convention. Greenhouse strawberry is economic crop in agriculture, and its cultivation area and yield has been increased. Therefore, we tried to investigate the POPs residue in greenhouse soil and strawberry.METHODS AND RESULTS: Extraction and clean-up method for the quantitative analysis of OCPs was developed and validated by gas chromatography (GC) with electron capture detector (ECD). The clean-up method was established using the modified quick, easy, cheap, effective, rugged, and safe(QuEChERS) method for OCPs in soil and strawberry. Limit of quantitation (LOQ) and recovery rates of OCPs in greenhouse soil and strawberry were 0.9-6.0 and 0.6-0.9 μg/kg, 74.4-115.6 and 75.6-88.4%, respectively. The precision was reliable sincerelative standard deviation (RSD) percentage (0.5-3.7 and 2.9-5.2%) was below 20, which was the normal percent value. The residue of OCPs in greenhouse soil was analyzed by the developed method, and dieldrin, β-endosulfan and endosulfan sulfate were detected at 1.6-23, 2.2-28.4 and 1.8-118.6 μg/kg, respectively. Those in strawberry were not detected in all samples.CONCLUSION: Dieldrin, β-endosulfan and endosulfan sulfate in a part of investigated greenhouse soil were detected. But those were not detected in investigated greenhouse strawberry. These results showed that the residue in greenhouse soil were lower level than bioaccumulation occurring.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.135-140
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• 2012

In this study, the heats of absorption of $CO_2$ with aqueous solutions of primary, secondary and tertiary amine aqueous solutions were measured in the commercial reaction calorimeter SIMULAR (HEL, UK). The heats of absorption of 30 wt% amine aqueous solutions of MEA (monoethanolamine, primary amine), EAE(2-(ethylamino)ethanol, secondary amine), and MDEA (methyldiethanolamine, tertiary amine) were measured as function of the $CO_2$ loading ratio at $40^{\circ}C$, in each case. In addition, the heats of absorption of sterically-hindered amine aqueous solutions of AMP(2-amino-2-methyl-1-propanol, primary amine), DEA(diethanolamine, secondary amine) and TEA(triethanolamine, tertiary amine) were measured to observe the steric hindrance effect. The heat of absorption is high in the following order regardless of the steric hindrance: primary amine > secondary amine > tertiary amine. The heats of absorption of amines having sterically-hindered substituents surrounding nitrogen atoms are relatively low compare to that of sterically-free amines, although the difference is very small.