• Advances in nano research
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• 제6권1호
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• pp.1-19
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• 2018

Iron oxide nanoparticles excite researcher interest in biomedical applications due to their low cost, biocompatibility and superparamagnetism properties. Magnetic iron oxide especially magnetite ($Fe_3O_4$) possessed a superparamagnetic behaviour at certain nanosize which beneficial for drug and gene delivery, diagnosis and imaging. The properties of nanoparticles mainly depend on their synthesis procedure. There has been a massive effort in developing the best synthetic strategies to yield appropriate physico-chemical properties namely co-precipitation, thermal decomposition, microemulsions, hydrothermal and sol-gel. In this review, it is discovered that magnetite nanoparticles are best yielded by co-precipitation method owing to their simplicity and large production. However, its magnetic saturation is within range of 70-80 emu/g which is lower than thermal decomposition and hydrothermal methods (80-90 emu/g) at 100 nm. Dimension wise, less than 100 nm is produced by co-precipitation method at $70^{\circ}C-80^{\circ}C$ while thermal decomposition and hydrothermal methods could produce less than 50 nm but at very high temperature ranging between $200^{\circ}C$ and $300^{\circ}C$. Thus, co-precipitation is the optimum method for pre-compliance magnetite nanoparticles preparation (e.g., 100 nm is fit enough for biomedical applications) since thermal decomposition and hydrothermal required more sophisticated facilities.

• 한국산업경영시스템학회:학술대회논문집
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• 한국산업경영시스템학회 2002년도 춘계학술대회
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• pp.387-396
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• 2002

Batch processes are a significant class of processes in the process industry and play an important role in the production of high quality speciality materials. Examples include the production of semiconductors, chemicals, pharmaceuticals, and biochemicals. With on-line sensors connected to most batch processes, massive amounts of data are being collected routinely during the batch on easily measured process variables such as temperatures, pressures, and flowrates. In this paper, multivariate SPC charts for on-line monitoring of the progress of new batches are developed which utilize the information in the on-line measurements in real-time. We propose the formation of statistical model which describes the normal operation of a batch at each time interval during the batch operation. An on-line monitoring scheme based on the proposed method can handle both cross-correlation among process variables at any one time and auto-correlation over time. And the control limits for the monitoring charts are established from sound statistical framework unlike previous researches which use the external reference distribution. The proposed charts perform real-time, on-line monitoring to ensure that the batch is progressing in a manner that will lead to a high-quality product or to detect and indicate faults that can be corrected prior to completion of the batch. This approach is capable of tracking the progress of new batch runs, identifying the time periods in which the fault occurred and detecting underlying cause.

• 만화애니메이션 연구
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• 통권26호
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• pp.57-78
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• 2012

디지털 테크놀로지의 확산은 디즈니의 드로잉 애니메이션 제작방식을 아날로그방식에서 디지털방식으로 근본적으로 변화시켰다. 이러한 변화로 인하여 복제나 변형, 혼합이 용이한 디지털 매체의 특성이 디즈니 드로잉 애니메이션에 이식되었고, 결과적으로 드로잉 애니메이션의 표현영역을 확장시키며 디즈니 애니메이션의 전체적인 질을 향상 시키는데 기여하였다. 그러나 한편으로는 전반적인 장편 애니메이션 시장이 3D 컴퓨터 애니메이션을 중심으로 재편되면서 디즈니 장편 드로잉 애니메이션 제작을 크게 위축시키는 결과를 가져오기도 했다. 현재 디즈니 드로잉 애니메이션은 디지털 테크놀로지의 과도기적인 수용단계를 지나 드로잉 애니메이션 특유의 따뜻한 감성과 풍부한 표현력을 컴퓨터 그래픽 기술을 이용하여 표현하고, 확장시키며 새로운 가능성을 실험해보고 있는 단계라고 할 수 있을 것이다. 디지털 테크놀로지를 사용하되, 테크놀로지 종속적인 관계에서 벗어나 드로잉 애니메이션 특유의 미학적 가치를 발전시키고 강화하는 것이 오늘날 디즈니 드로잉 애니메이션이 추구하고자 하는 방향일 것이다.

• 한국염색가공학회지
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• 제32권4호
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• pp.255-264
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• 2020

With the development of synthetic dyes, excellent dyeing properties and massive production became possible. On the other hand, natural dyeing technology has gradually disappeared. However, the international environmental and human safety requirements of the apparel and textile industry are increasing, and there is a growing interest in safer and more environmentally friendly products. Accordingly, the public's interest in natural dyeing is increasing. To meet these demands, it is first necessary to clarify the stages of production and distribution of natural dyes. It is necessary to evaluate whether the product is a natural dye product and study the suitability of the natural dye product through qualitative and quantitative assessment of the indicator components of the natural dye. Typical of three natural dyes did qualitative and quantitative analysis by HPLC-DAD and HPLC-MS. Products dyed using natural dye three products were analyzed, and the presence or absence of detection of each indicator components was confirmed to confirm whether the product was dyed using natural dyes.

• 대한한의학방제학회지
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• 제18권1호
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• pp.169-179
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• 2010

The pistil of nelumbo nucifera (PNN) is used in the treatment of nocturnal pollution, hematemesis, epistaxis, metrorrhagia and diarrhoea in traditional medicine. The present study was examined to evaluate the effects of PNN on the production of pro-inflammatory mediators in vitro. After the treatment of PNN, cell viability was measured by MTT assay, nitric oxide (NO) production was monitored by measuring the nitrite content in culture medium. The protein bands were determined by immunoblot analysis and levels of cytokines were analyzed by sandwich immunoassays. In the MTT assay, the doses of PNN extract (0.03, 0.10 mg/ml) had no significant cytotoxicity. The increases of NO production and inducible nitric oxide synthase expression were detected in lipopolysaccharide(LPS)-activated Raw 264.7 cells compared with control, in contrast, these increases were significantly attenuated by pre-treatment with PNN. In cytokine assay, the massive pro-inflammatory cytokines such as tumour necrosis factor-$\alpha$, interleukin (IL)-$1{\beta}$ and IL-6 were induced in LPS-activated Raw 264.7 cells, but pre-treatment of Raw 264.7 cells with PNN caused inhibition (TNF-$\alpha$=14.17%, IL-$1{\beta}$=107.43%, IL-6=46.27%) the production of cytokines by LPS. In addition, PNN reduced prostaglandin E2 productions in a dose-dependent manner (0.03mg/ml=37.52%, 0.10 mg/ml=83.77%) as a consequence of the inhibition of cyclooxygenase-2 expression. Taken together, our data indicates that PNN can regulate the inflammatory response in macrophage cells activated by Gram-negative infection.

• 한방안이비인후피부과학회지
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• 제23권2호
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• pp.125-138
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• 2010

Objective : The present study was examined to evaluate the effects of Ecliptae Herba on the production of inflammatory mediators in vivo and in vitro. Methods : In cell viability, all three doses of Ecliptae Herba extract (25, 50 and $100\;{\mu}g/ml$) had no significant cytotoxicity during the experimental period. The increases of NO production and iNOS expression were detected in LPS-activated cells compared to control, but these increases were dose-dependently attenuated by pre-treatment with Ecliptae Herba extract. Results : 1. LPS plays a pivotal roles in inducing to the massive production of pro-inflammatory cytokines such as TNF-$\alpha$, IL-$1{\beta}$ and IL-6 in macrophages. 2. Ecliptae Herba extract reduced the elevated production of cytokines by LPS. 3. Ecliptae Herba extract reduced $PGE_2$ levels in a dose-dependent manner as a consequence of inhibition of COX-2 activity. 4. Ecliptae Herba extract significantly reduced the nuclear translocation of $NF-{\kappa}B$ induced by LPS. 5. In histopathological study, Ecliptae Herba effectively inhibited the increases of hind paw edema, skin thicknesses and inflammatory cell infiltrations induced by carrageenan treatment. Conclusions : These results provide evidences that therapeutic effect of Ecliptae Herba on the acute inflammation is partly due to the reduction of some of inflammatory factors by inhibiting iNOS and COX-2 through the suppression of $NF-{\kappa}B$.

• Archives of Pharmacal Research
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• 제26권12호
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• pp.1067-1073
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• 2003

Ursodeoxycholic acid (UDCA) is a non-toxic, hydrophilic bile acid in widespread clinical use mainly for acute and chronic liver disease. Recently, treatment with UDCA in hepatic graft-versus-host disease has been given in immunosuppressive therapy for improvement of the biochemical markers of cholestasis. Moreover, it has been reported that UDCA possesses immunomodulatory effects by the suppression of cytokine production. In the present study, we hypothesized that UDCA may inhibit the production of the pro-inflammatory cytokine, IL-1$\beta$, and nitric oxide (NO) in microglia. In the study, we found that 100 $\mu$ g/mL UDCA effectively inhibited these two pro-inflammatory factors at 24 hand 48 h, compared to the $A\beta$42-pretreated groups. These results were compared with the LPS+UDCA group to confirm the UDCA effect. As microglia can be activated by several stimulants, such as $A\beta$42, in Alzheimers brain and can release those inflammatory factors, the ability to inhibit or at least decrease the production of IL-1$\beta$ and NO in Alzheimers disease (AD) is essential. Using RT-PCR, ELISA and the Griess Reagent System, we therefore found that UDCA in $A\beta$42 pre-treated cultures played a significant role in suppressing the expression or the production of IL-1$\beta$ and NO. Similarly, lipopolysaccharide (LPS) did not activate microglia in the presence of UDCA. Moreover, we found that UDCA exhibits a prolonged effect on microglial cells (up to 48 h), which suggests that UDCA may play an important role in chronic cell damage due to this long effect. These results further imply that UDCA could be an important cue in suppressing the microglial activation stimulated by massive AD peptides in the AD progressing brain.

• 정보보호학회논문지
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• 제25권3호
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• pp.627-637
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• 2015

온라인 게임시장의 성장으로 아이템 거래시장이 활성화됨에 따라 아이템 현금 거래시장은 1조 6,000억원 규모로 성장하였으며, 활성화된 시장으로 인해 아이템 및 게임머니의 현금화가 용이하게 되었다. 이러한 특성으로 악의적인 사용자들은 온라인 게임에서 계정도용을 통해 금전적인 가치가 높은 희귀 아이템 및 게임머니를 탈취하여 현금화하는 사례가 빈번히 발생하고 있는 실정이다. 본 연구에서는 MMORPG(Massive Multi-user Online Role Playing Game)내에서의 계정도용자들의 행위분석을 통한 계정도용 탐지모델을 제안한다. 계정도용의 경우 현금화 시킬 수 있는 아이템 및 게임머니를 탈취해야하기 때문에 게임 행동상에서 경제활동에 치중되어 있으며 아이템 생산, 아이템 판매, 게임머니 획득 이라는 특정 시퀀스를 가지고 있다. 이를 기반으로 계정도용 탐지모델을 제안하였으며, 본 논문의 탐지모델을 활용하여 분류한 결과 84%의 정확도를 보였다. 더불어 거래 네트워크 분석을 통해 계정도용 시 발생하는 거래특성에 대해 분석하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.47-49
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• 2006

The Sea of Okhotsk is the unique area providing the highest methane production rate of the northern hemisphere. The area of focused fluid venting offshore the NE Sakhalin continental slope was investigated during the CHAOS (Hydro-Carbon Hydrate Accumulations in the Okhotsk Sea) expeditions onboard of RV "Akademik Lavrentyev" In 2003, 2005 and 2006. The International Research Project CHAOS (Russia-Korea-Japan) aimed at the study of gas hydrate formation processes associated with the fluid venting in the Sea of Okhotsk. Several new gas hydrate accumulations were discovered during the cruise. Hydrate-associated structures have been named as KOPRI, VNIIOKeangeologia, POI and KIT (the names of cruise participant institutes) Some of hydrate-bearing cores contain big amount of gas hydrates: massive gas hydrate layers (up to 35cm thick) were recovered. The shallowest submarine gas hydrate accumulations in the world (at the depth less then 400m) were discovered during the cruise.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.299-304
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• 1999

Cracking of concrete is one of the main issues of structural design next to ensuring the load-bearing capacity. Thermal cracking is a recurring concern in the production of concrete structures in particular when large, massive structures are considered. Thremal stresses arise from the differential temperature distribution either within s sturcture or between newly cast sectons and adjoining older parts. There are many different methods of reducing thermal stresses. A method often used for reducing temperature within a structure, is to cool the inner core with embedded cooling pipes. In this study, finite element method is employed for thermal analysis of concrete structures. To calculate water temperature variation in pipe, the conservation of thermal energy in internal flow was adopted. The cooling effect of pipe cooling is studied with several factors like convective coefficient, water temperature, concrete heat characteristics