• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.713-719
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• 2016

The NOx conversion properties of Mn-Cu-$TiO_2$ and $V_2O_5$/$TiO_2$ catalysts were studied for the selective catalytic reduction (SCR) of NOx with ammonia. The performance of the catalysts was investigated in terms of their $NOx$ conversion activity as a function of the reaction temperature and space velocity. The activity of the Mn-Cu-$TiO_2$ catalyst decreased with increasing reaction temperature and space velocity. However, the activity of the $V_2O_5$/$TiO_2$ catalyst increased with increasing reaction temperature. High activity of the Mn-Cu-$TiO_2$ catalyst was observed at temperatures below $200^{\circ}C$. H2-TPR and XPS analyses were conducted to explain these results. It was found that the activity of the Mn-Cu-$TiO_2$ catalyst was influenced by the thermal shock caused by the change of the initial reaction temperature, whereas the $V_2O_5$/$TiO_2$ catalyst was not affected by the initial reaction temperature. In the case of catalyst C, the $NO_x$ conversion efficiency decreased with increasing space velocity. The decrease in the $NO_x$ conversion efficiency with increasing space velocity was much less for catalyst D than for catalyst C.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.2
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• pp.163-170
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• 2014

Lipid membranes composed of phosphatidylcholine (PC) are used in biophysical study to mimic cellular membranes and interactions between the membrane and chemicals, where organics solvents are used in dissolving lipids or chemicals. Later, solvents are removed from the solution under nitrogen gas at room temperature, followed by the further removal of the solvent at vacuum condition for several hours. In this process, some solvents are easily removed under described conditions above and others are required more severe conditions. In this study, $^{31}P$ solid-state nuclear magnetic resonance (SSNMR) techniques and differential scanning calorimetry (DSC) were used to see any changes in the line shapes of $^{31}P$ NMR spectra of multilamellar vesicles (MLVs) samples of POPC and in the phase change temperature of multilamellar vesicles (MLVs) of DPPC in DSC thermogram with or without any residual solvents. The thermodynamic parameters associated with the solvents did exhibit noticeable changes depending on solvent types. Thus, it is concluded that solvents should be carefully chosen and removed completely and experimental results should also be interpreted with caution particularly for the experiments investigating lipid phase changes and related topics.

• Journal of Oral Medicine and Pain
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• v.38 no.4
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• pp.313-318
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• 2013

The aim of this study was to the relationship between sleep disturbances and Burning mouth syndrome(BMS). BMS presents as a chronic burning sensation in the oral mucous membrane that is frequently associated with sleep disturbances. BMS is considered neuropathic pain condition with dysfunction of small diameter afferent sensory fiber. A review of the studies reveals, BMS suggested peripheral and cental nervous system changes. Sleep disruption or Rem sleep deprivation cause an inhibition of opioid protein synthesis and a reduced affinity of ${\mu}$ and ${\delta}$ opioid receptors. Let me say that sleep disturbances suggest a risk factor For BMS and support to evaluate as a part of BMS treatment. Further study will be required to ascertain the relationship between distruption of sleep continuity or Rem sleep deprivation and BMS and the evidence of altered neurochemical degeneration of BMS.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.348-355
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• 2008

Recently, an understanding of new sources of liquid hydrocarbons such as bio-ethanol is economically very important. The present dissertation is also designed with purpose of developing the energy-saving process for the separation of bio-ethanol. In order to illustrate the predictability of proposed process for the separation of bio-ethanol, the experimental data from literatures and real plant data are used. Application of the thermodynamics of multicomponent mixtures and phase equilibria to the extractive distillation process with syntheses of heat exchanger network has enabled the development of energy-saving process for different separating agents. Developed process is capable of minimizing the energy usage and the environmental effect. This extractive process is also able to properly describe the effect of impurities, the choice of separating agent. Simulation results of extractive distillation using ethylene glycol show that impurities do not affect to extractive distillation operation and agent, ethylene glycol, was recycled without any loss. It is possible that extraction distillation has various heat network for anhydride ethanol and recovery of ethanol is maximized. Ethylene glycol as separating agent has a high boiling point to eliminate azeotropic point and on the contrary solubility of agent is low to be almost completed recovered. Proposed process is also the energy efficient process configuration in which 99.85mole% anhydride ethanol can be produced with low energy of 1.37198 (kg steam/kg anhydride ethanol).

• Journal of Periodontal and Implant Science
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• v.34 no.2
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• pp.243-253
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• 2004

최근의 레이저 기술의 발전은 치의화영역에서 많은 가능성을 제시해 주고 있으며, 레이저를 이용한 외과적 치료의 기전과 안전성은 많은 분야에서 입증되어 있다. 근래에는 치주학적 분야에도 레이저를 적용하려는 노력이 계속되어 왔으며, 치석의 제거나 치근면의 세균제거 등에서 효과를 제시한 연구들이 있었다. 본 연구의 목적은 $CO_2$ 레이저를 통상적 치은연하소파술과 병용하였을때의 임상적 효과를 임상 지수의 측정을 통하여 평가하는 것이다. 만성 중둥도-고도의 치주염으로 진단된 12명의 환자가 본 임상연구에 포함되었다. 한 환자에서 각각 2부위의 사분악을 선택하여 임의로 2가지 치료군에 다음과 같이 나누어 포함시켰다: 1) 치은연하 소파술만을 적용한 사분악을 대조군 2) 치은연하 소파술과 0.8W의 에너지 수준을 갖는 $CO_2$ 레이저를 병용하여 적용한 사분악을 Laser 군으로 포함하였다. 치주낭 탐침 깊이, 임상 부착 수준, 치은 퇴축 및 탐침시 출혈풍의 임상지수를 치료전과 술후 각각 1, 3, 6개월 경과시에 측정하여 다음과 같은 결과를 얻었다. 치주낭 탐침 깊이, 임상 부착 수준, 치은 퇴축 및 탐침시 출혈 등의 모든 측정한 임상지수에서 치료전 ${\cdot}$ 후를 비교하였을 때 통계적으로 유의한 개선을 보였다. 그러나 실험군과 대조군간의 비교에서는 치주낭 탐침 깊이, 임상 부착 수준에서는 통계적으로 유의한 차이를 보이지 않았다. 탐침시 출혈은 술후 6개월시에 Laser군에서 대조군에 비하여 통계적으로 유의성있는 차이를 보이며 감소하였다(p<0.05). 결론적으로 $CO_2$ laser를 비외과적 치주 치료에 부가적으로 적용하였을 때 염증 감소에 기여할 가능성이 있을 것으로 사료된다.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.1
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• pp.127-152
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• 2020

Despite growing international cooperation for maintenance of international peace and security, wars continue to occur due to conflicted state interests. Continuing conflicts has advanced development of various weapon systems such as global integrated intelligence, surveillance and reconnaissance. However, with a big increase in the number of civilian casualties caused by the weapon systems development, the international community has also advanced diplomatic efforts to minimize deaths of civilian and military personnel. Therefore, it is essential to observe the principle of discrimination between combatants and non-combatants when operating unmanned aerial vehicles (UAVs), better known as drones. Drones have become more capable of distinguishing combatants from non-combatants due to its high-tech prowess. In the operation of drones, any parties involved in combat or the war are responsible for mounting civilian casualties. In addition, it should comply with the principle of proportionality that calls for a balance between results of such action and expected military advantage anticipated from the attack. The rule of proportionality prohibits use of military force which may be expected to cause excessive civilian harm. Drones have been able to track and monitor targets for hours and select the accurate locations of the targets. The aim is to reduce civilian losses and damage to a minimum. Drones meet the standards of Article 51.4 of the Additional Protocol.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.637-642
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• 1993

Changes in the physicochemical characteristics and triglyceride molecular species of corn oil under the following condition of hydrogenation; temperature $180^{\circ}C,\;H_{2}$, pressure $2.0{\pm}0.3bar$, the amount of Ni catalyst 0.048%(Ni/oil by wt.) and agitation speed 300 rpm. The rate of hydrogenation, expressed as the reduction rate of the iodine value with respect to time, is first order and high (K>0.01). When the reduction rate of the iodine value was 39.9%, hydrogenation time was 30 min, 18:1 was highest(77.06%), thereafter that was decreased and 18:0 increased. In the triglyceride composition, OLL, LLL were reduced markedly in 10 min, thereafter reduced slightly. And PLO, PLL, OLO were eliminated in first 30 min. On the other hand, POO, PLS(CN52) and OOO, SLO(CN54) were increased sharply, and then that showed little change. The melting point(MP) of hydrogenated corn oil were $27.8^{\circ}C\;and\;44.1^{\circ}C$ after 20 min and 60 min, respectively. Trans isomer content increased to 46.8% during 40 mins of hydrogenation and then decreased insignificantly. The solid fat content were linearly increased with hydrogenation time. Accordingly, it is confirmed that this condition of hydrogenation was selective, preferential elimination of polyunsaturated fatty acid went stepwise and trans isomer was formed promotedly. These results suggest that fat modification techniques can be used for practical application.

• Journal of the Korean Institute of Gas
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• v.20 no.2
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• pp.1-9
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• 2016

Combined removal of n-heptane and carbon monoxide (CO) using a plasma-catalytic process was investigated. The performance of the plasma-catalytic process was compared with that of the catalyst-alone process to characterize the decomposition of n-heptane and CO with the operation parameters such as the type of catalyst, reaction temperature, and discharge power. From several sets of experiments, it was found that the decomposition efficiency of n-heptane mainly depended on the specific input energy rather than the reactor temperature, whereas the oxidation of CO on both the energy density and the reaction temperature. The results conducted over several metal oxide catalysts exhibited that the decomposition efficiency of n-heptane was in the order: $Pd/{\gamma}-Al_2O_3$ > $Ru/{\gamma}-Al_2O_3{\approx}Ag/{\gamma}-Al_2O_3$. Especially, $Pd/{\gamma}-Al_2O_3$ catalyst did hardly generate CO as a byproduct during the decomposition of n-heptane under an appropriate condition, revealing $CO_2$ selectivity of nearly 100%. The CO oxidation efficiency was largely affected by the type of catalyst ($Pd/{\gamma}-Al_2O_3$ > $Ru/{\gamma}-Al_2O_3$ > $Ag/{\gamma}-Al_2O_3$). At temperatures below $180^{\circ}C$, the plasma-catalytic process was more effective in the oxidation of CO, while above $180^{\circ}C$, the catalytic process resulted in slightly higher CO oxidation efficiency.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1119-1125
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• 2002

The growth of C. pefringens was inhibited by the combination of natural products which have antioxidative capacity C. perfringens was controlled very effectively by each or the combination of Paeonia japonica, Atractylodis rhizome alba, Epimedii herba, Acori graminei rhizoma, Schizandraefructus, Lyciifructus, Cinnamomi cortex Sophorae flos Phellodendri cortex, Nelumbo nuclfera gaertner, Asparagi tuber, Mori cortex radicis, Astrafali radix and Coptidis rhizome The combination of Phellodendri cortex, Epimedii herba, Astragali radtx and Glycyrrhizae radix inhibited the growth of C. pefringen by 75% and increased the antioxidative activity by 4.4 times. This combination also eliminated more than 80% of hydroxyl radical. These natural products can be utilized as pharmaceuticals, functional foods, antiaging tea, and multifunctional fermentative beverages.

• 한국지형공간정보학회:학술대회논문집
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• 2002.03a
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• pp.106-112
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• 2002

최근 급속한 도시의 팽창 및 신도시 건설과 산업의 발전으로 가스시설은 꾸준히 확대되고 있는 실정이다. 그리고 94년 아현동 도시가스사고와 95년 대구 도시가스사고 이후로 도시 가스 시설물의 대한 안전 대책 및 시설물 관리에 대한 국민들의 관심이 증대되었다. 이러한 흐름에 따라 가스회사들은 GIS 기술을 도입하여 기존에 수작업으로 관리되고 있는 가스시설 정보체계를 전산화하여 항상 최신의 현황을 유지하고, 사고 발생시 신속한 대처 방안 및 피해예측을 위한 시스템을 개발하기 위하여 많은 연구를 진행하고 있는 실정이다. 본 연구의 목적은 안전이 중요시되는 가스시설물에 대하여 가스사고 발생시 신속한 대처 및 처리방안을 제시할 수 있는 GIS 기반의 가스사고 관리시스템을 개발하는데 있다. GIS의 가스사고 관리시스템에서는 사고 발생시에 시설물 관리자가 사고 지점을 선택하여 우선적으로 공급을 중단해야 할 관로를 제시하고 사고지점을 검색하여 차단해야 할 밸브에 대한 정보를 신속히 제공하여 대응 방안을 제시 할 수 있도록 하였다. 아울러 가스공급이 중단되는 지역에 대한 정보를 추출하여 피해범위를 산정하여 효율적인 사고 관리를 지원하도록 구성되었으며, 이와 함께 잔존가스량을 구하여 사고후의 대처방안을 마련할 수 있는 기능을 제공하도록 하였다. 향후 연구과제로는 원격으로 가스 시설물을 감시하고 제어할 수 있는 원격감시/제어시스템(SCADA System)과 연계를 통하여 가스사고 후에 신속한 피해예측 및 피해를 최소화 할 수 있는 방안제시 및 GPS를 활용하여 신속한 사고처리를 할 수 있는 활용 방안을 연구하여 체계적이고 종합적인 가스사고의 관리가 필요하다고 사료된다. 또한, 사고 후의 긴급 대처방안 뿐만 아니라 잔존가스량을 이용하여 수용가에 가스의 신속한 재공급을 위한 정보의 제공까지 한 단계 발전된 시스템의 개발이 추진되어야 한다.남산지역에 대해 정사영상과 10m간격의 DEM을 제작하였으며 1:1000 수치지도를 통해 제작된 DEM과 비교한 결과 총 43990개 격자점의 표고 차이는 평균 5.98m였다.여재 높이 100 cm에서 원수를 하향류 및 상향류로 주입하면서 하향류 20, 40, 80, 100 cm, 상향류 20, 40, 60, 80, 100 cm에서 시료를 채취하여 분석한 결과 모두 원수가 주입되는 부근 여재 높이 20 cm에서 가장 많이 제거되었다. 상향류 보다 하향류로 원수를 주입했을 때 제거효율이 높았다. $Fe^{+++}$을 $Fe^{++}$로 환원하는 $O^{-}_{2}{\cdot}$의 작용을 대신할 수 있음을 증명하며 이와같은 ascorbate 의존적인 $OH{\cdot}$ 의 생성은 ascorbate가 조직손상에 관여할 가능성을 시사하였다.었다. 정확한 예측치를 얻기 위하여 불균질 조직이 조사야에 포함되는 경우 보정이 요구되며, 골반의 경우 골 조직의 보정이 중요한 요인임을 알 수 있었다. 이를 위하여 불균질 조직에 대한 정확한 정보가 요구되며, 이는 CT 영상을 이용하는 것이 크게 도움이 되리라 생각된다.전시 슬러지층과 상등액의 온도차를 측정하여 대사열량의 발생량을 측정하고 슬러지의 활성을 측정할 수 있는 방법을 개발하였다.enin과 Rhaponticin의 작용(作用)에 의(依)한 것이며, 이는 한의학(韓醫學) 방제(方劑) 원리(原理)인 군신좌사(君臣佐使) 이론(理論)에서 군약(君藥)이 주증(主症)에 주(主)로 작용(作用)하는 약물(藥物)이라는 것을 밝혀주는 것이라고 사료(思料)된다.일전 $13.447\;{\mu}g/hr/g$, 섭취 7일중 $8.123\;{\mu}g/hr/g$, 절식 14일후 $10.612