• 한국방재학회:학술대회논문집
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• 2010.02a
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• pp.116-116
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• 2010

기후변화로 인해 점차 이상기후가 심해짐에 따라 폭염이나, 한파와 같은 극한 기상현상에 의한 피해가 증가하고 있다. 이중에서도 특히 폭염에 의한 피해는 인명피해 발생과 관련성이 크다. 이에 따라 본 연구에서는 폭염시기의 종관기상학적인 특성 분석을 통해 인명피해를 가져오는 폭염의 기상학적인 특성을 분석하고자 하였다. 그 결과, 폭염으로 인한 초과사망자수의 발생이 많았던 1994년 7월 21일을 전후로 하여, 건강에 영향을 미칠 수 있는 종관규모의 기류의 영향이 발생함을 확인할 수 있었다.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.106-111
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• 2012

Drying characteristic of high moisture coal using a 5 kg/hr bench scale flash dryer was investigated. Moisture content and heating value of raw coal as received basis were 29.74 wt% and 4,270 kcal/kg, respectively. Gas inlet temperature and gas inlet flow rate were $400{\sim}600^{\circ}C$ and 10~20 m/sec, respectively. The raw coal was ground and classified to the particle size range of $100{\sim}2,000{\mu}m$. The moisture removal rate of raw coal was dramatically increased with increasing gas inlet temperature and decreasing gas inlet flow rate. The heating value of dried coal was increased to 5,100~5,900 kcal/kg. To examine the chemical change on the surface of high moisture coal during flash drying process, FT-IR spectral analysis was carried out. As a result, major changes in hydroxyl, carboxyl and carbonyl peak was confirmed.

• Journal of Korean Tunnelling and Underground Space Association
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• v.12 no.1
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• pp.43-49
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• 2010

The escape connecting gallery in a tunnel on a road is one of emergency equipment to ensure safety for passer in the tunnel against the tunnel fire. Government stipulate over 500m tunnel has the cross passage at intervals of less then 250 m. However, this lump estimated interval is generated the concerns of exaggeration and under construction because peculiarity of the tunnel ex. The velocity of the tunnel airflow, an incline, degree of a fire, and innering area are not considered. The study indicate the way to estimate of the cross passage considered an incline and the velocity of the tunnel airflow for efficient application of cross passage on the tunnel design. As a result, in 0.0 m/s and 1.0 m/s of the velocity of the tunnel airflow case, the movement of smoke is influenced by the incline however, in 20 m/s case, it isn't influenced by incline much. According to the velocity of tunnel airflow and the incline, optimum interval of cross passage is not corresponded. Therefore established lump estimate that has 250 m intervals would be changed to estimate of optimum interval of cross passage that considered about the properties of tunnel, the velocity of the tunnel airflow, incline, degree of a fire and innering area of the tunnel.

• Fire Science and Engineering
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• v.25 no.3
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• pp.85-90
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• 2011

This study of the vestibule of pressurizing smoke control system installed in domestic high-rise buildings for evacuation in case of fire, when the door is open to forming characteristics of the air flow was analyzed using fire dynamics simulator and analyzed of variance. Vestibule which is compartment of the design condition, air flow in the exhaust damper was formed severe turbulence confirming preceding research. The door position is in the range of formed vortex, unsteady flow of air occurs at the point that the door could be confirmed. According to the NFSC 501A, door to symmetrically separate the average of 10 points or more as measured from the average of wind speed to do is based. Under these conditions, it is difficult to measure the characteristics of the upper air flow of upper points. so measuring points are subdivided by more than 64 points method presented in TAB because severe deviation of wind speed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.219-225
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• 2011

The physicochemical properties of rice endosperm from five rice varieties and effects of milling on baking bread properties of rice flour were investigated. Five rice varieties exhibited different level of amylose content. The ratio of longer amylopectin chain length to the distribution of endosperm starches was the highest in Goami3. According to the RVA measurement of rice flours, the pasting temperatures of Seolgaengbyeo and Goamibyeo were lower than those of the other rice varieties. There were differences in the changes of swelling power of rice flour under increasing temperature. Each rice flour sample for bread-making was processed into two different particle size by using an air-classification mill, and significant differences were observed among cultivars in the average particle size and damaged starch content of rice flours. Rice flour of Seolgaengbyeo with fine particle size showed the highest value in specific volume after baking.

• Journal of the Korean Geographical Society
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• v.34 no.2
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• pp.123-136
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• 1999

본 연구에서는 제주도의 사면별 강수 분포 특성을 파악하고자 하였다. 기압배치와 상층 풍향별로 4개 기상관측소의 일별 강수량 자료를 분석하였다. 제주도의 강수량은 북서사면 보다 남동사면 쪽이 많다. 그리고 대부분 온대성 저기압과 장마전선, 태풍에 의한 것이며, 앞의 두 경우는 남.동사면, 태풍에 의한 것은 북사면에 많다. 태풍에 의한 호우는 사면간의 강수량 차이가 적고, 저기압에 의한 것은 동서사면간, 장마전선에 의한 것은 남북사면간의 차이가 크다. 풍향별로는 남동과 남서풍계에 의한 강수가 많은데, 겨울에는 북서풍계에 의한 강수도 많다. 기압배치형 보다는 기류의 방향에 따라서 사면간의 강수량 차이가 크며, 남서, 남동풍계가 우세한 여름에는 남사면 강수량이 많고, 북서와 북동풍계가 우세한 겨울에는 북사면이 많다. 사면간의 강수차이는 미우인 경우 더욱 뚜렷하고, 미우는 겨울 북사면에 많다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.101-102
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• 2002

동북아시아 지역은 전 세계적으로 인구가 조밀하고 경제발전 속도가 빠른 지역으로, 이에 따라 막대한 양의 대기오염물질이 배출되고 있다. 이 지역의 대기오염 특성으로는 (1) 막대한 양의 인위적인 대기오염물질 배출, (2) 흙먼지의 배출, (3) 편서풍을 들 수 있다 (문길주 등, 1996). 본 연구에서는 동북아시아 지역을 대상으로 기류이동의 변화에 따라 대기오염물질의 분포가 어떻게 달라지는가를 보고자 하였으며, 이를 위하여 우리나라 시간으로 1999년 5월 6-7일과 5월 11-12일의 바람장 및 대기오염물질의 농도 변화를 비교 분석하였다. (중략)

• Journal of Korean Society of Environmental Engineers
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• v.36 no.5
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• pp.325-332
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• 2014

Growing concerns about harmful influence of radon on human body, many efforts are being made to decrease indoor radon concentration in advanced countries. To develop an indoor radon reduction technology, it is necessary to develop a technology to predict and evaluate indoor inflow and emission of radon. In line with that, the present study performed computational modelling of indoor dispersion of radon emitted from building materials. The computational model was validated by comparing computational results with analytical results. This study employed CFD (Computational Fluid Dynamics) analysis to evaluate the radon concentration and the airflow characteristics. Air change rate and ventilation condition were changed and several building materials having different radon emission characteristics were considered. From the results, the indoor radon concentration was high at flow recirculation zones and inversely proportional to the air change rate. For the different building materials, the indoor radon concentration was found to be highest in cement bricks, followed by eco-carats and plaster boards in the order. The findings from this study will be used as a method for selecting building materials and predicting and evaluating the amount of indoor radon in order to reduce indoor radon.

• Analytical Science and Technology
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• v.27 no.4
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• pp.213-222
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• 2014

The atmospheric aerosols of $PM_{10}$ and $PM_{2.5}$ were collected at Gosan site of Jeju Island during 2012- 2013. Their ionic and elemental species were analyzed in order to examine the composition variation of the haze aerosols in accordance with the pathway of air mass. The concentrations of $nss-SO_4{^{2-}}$, $NO_3{^-}$, and $NH_4{^+}$ increased 2.1~3.7 times in coarse particle and 3.1~6.5 times in fine particle modes, respectively, showing especially high $NO_3{^-}$ concentrations in fine particles during the haze days. The concentrations of S, Zn, Pb and K increased 3.0~5.6 times in coarse particles and 3.2~7.7 times in fine particles during the haze days, on the other hand Al, Fe, and Ca concentrations were high only in coarse particles. Due to the back trajectory analysis, the concentrations of $nss-SO_4{^{2-}}$ and $NO_3{^-}$ for haze days were high when the inflow pathway of air mass was from China, especially a high increase of $NO_3{^-}$ as through the south of China. The $NO_3{^-}/nss-SO_4{^{2-}}$ concentration ratio was relatively high in coarse mode as air mass inflow from China, but in fine mode it was high as air mass passing through the Korean peninsula.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4666-4672
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• 2011

Performance of NOx removal in SCR(Selective Catalytic Reduction) process depends on such various factors as catalyst factors (catalyst composition, catalyst form, space velocity, etc.), temperature of exhaust gas, and velocity distribution of exhaust gas. Especially the flow uniformity of gas stream flowing into the catalyst layer is believed to be the most important factor to influence the performance. In this research, the flow characteristics of a SCR process at design stage was simulated, using 3-dimensional numerical analysis method, to confirm the uniformity of the gas stream. In addition, the effects of guide vanes, baffles, and perforated plates on the flow uniformity for the inside and catalyst layer of the reactor were studied in order to optimize the flow uniformity inside the SCR reactor. It was found that the installation of a guide vane at the inlet duct L-tube part and the installation of a baffle at the upper part is very effective in avoiding chaneling inside the reactor. It was also found that additional installation of a perforated plate at the lower part of the potential catalyst layer buffers once more the flow for very uniform distribution of the gas stream.