• Journal of Energy Engineering
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• v.8 no.4
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• pp.540-545
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• 1999

The classical Fourier heat conduction equation is invalid at temperatures near absolute zero or at very early times in highly transient heat transfer processes. In such situations, a hyperbolic equation model for heat conduction based on the modified Fourier law is introduced because the wave nature of heat propagation becomes dominant. The Fourier model and the hyperbolic model for heat conduction are analyzed by using the Green's function technique together with the integral transform. Analytical expressions for the heat flux and temperature distributions in a finite slab subjected to a periodic surface heating at one of its surfaces are presented and the results obtained from each model are compared with each other. The thermal wave implied b the hyperbolic model is shown to travel through a medium and to reflect back toward the origin at the other insulated surface. On the other hand, the heat by the Fourier model propagates at an infinite speed instantaneously after a thermal disturbance is felt throughout the medium.

• Tuberculosis and Respiratory Diseases
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• v.44 no.2
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• pp.349-359
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• 1997

Background : The signal pathways and their precise roles for acute respiratory distress syndrome caused by endotoxin (ETX) has not been established. Since there has been several in vitro experiments suggesting that activation of protein kinase C (PKC) pathway may be responsible for endotoxin-induced inflammatory reaction, we performed in vivo experiments in the rats with the hypothesis that PKC-inhibition can effectively prevent endotoxin-induced acute lung injury. Methods : We studied the role of PKC in ETX-induced ALI using PKC inhibitor (staurosporine, STP) in the rat Specific pathogen free male Sprague-Dawley weighted from 165 to 270g were used for the study. Animals were divided into the normal control (NC)-, vehicle control (VC)-, ETX-, PMA (phorbolmyristateacetate)-, STP+PMA-, and STP+ETX-group. PMA (50mg/kg) or ETX (7mg/kg) was instilled through polyethylen catheter after aseptic tracheostomy with and without STP (0.2mg/kg)-pretreatment STP was injected via tail vein 30min before intratracheal injection (IT) of PMA or ETX. Bronchoalveolar lavage (BAL) was done 3-or 6-hrs after IT of PMA or ETX respectively, to measure protein concentration, total and differential cell counts. Results : The results were as follows. The protein concentrations in BALF in the PMA- and ETX-group were very higher than that of VC-group (p<0.001). When animals were pretreated with STP, the %reduction of the protein concentration in BALF was $64.8{\pm}8.5$ and $30.4{\pm}2.5%$ in the STP+PMA- and STP+ETX-group, respectively (p = 0.028). There was no difference in the total cell counts between the PMA-and VC-group (p = 0.26). However the ETX-group showed markedly increased total cell counts as compared to the VC- (p = 0.003) and PMA-group (p = 0.0027), respectively. The total cell counts in BALF were not changed after pretreatment with STP compared to the PMA- (p = 0.22) and ETX-group (p = 0.46). The percentage of PMN, but not alveolar macrophage, was significantly elevated in the PMA-, and ETX-group. Especially in the ETX-group, the percentage of PMN was 17 times higher than that of PMA (p < 0.001). The differential cell counts was not different between the PMA and STP+PMA On the contrary the STP+ETX-group showed decreased percentage of PMN (p = 0.016). There was no significant relationship between the protein concentration and the total or differential cell counts in each group. Conclusion : Pretreatment with PKC-inhibitor (staurosporine) partially but significantly inhibited ETX-induced ALI.

• Journal of the Korean School Mathematics Society
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• v.19 no.3
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• pp.239-260
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• 2016

Textbook is the most important material in learning and teaching school mathematics. It is necessary to develop highly utilizable mathematics textbook in view of normalization of public education including mathematics education. In this paper we first discuss the meaning of good mathematics textbook and analyze current mathematics textbooks to establish directions of highly utilizable mathematics textbook to student as well as teacher. And then we suggest a model and exemplary unit of highly utilizable mathematics textbook.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.2
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• pp.194-201
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• 2016

The anti-inflammatory activity of ethanol extract from Chondrus nipponicus Yendo (CNYEE) was investigated by measuring production of a lipopolysaccharide-induced inflammatory response mediator. CNYEE had no cytotoxic effects on proliferation of macrophages compared to the control. CNYEE significantly inhibited (over 50%) NO production at $50{\mu}g/mL$, with inhibitory effects on expression levels of cytokines such as interleukin (IL)-6, tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and IL-$1{\beta}$. In particular, IL-6 inhibitory activity of CNYEE was higher than 70% at $100{\mu}g/mL$. CNYEE also reduced protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor (NF)-${\kappa}B$ in a dose-dependent manner. CNYEE also significantly reduced phosphorylation of p38, extracellular signal-regulated kinase, and c-Jun N-terminal kinase. Therefore, these results suggest that CNYEE may have anti-inflammatory effects by modulating the NF-${\kappa}B$ and mitogen-activated protein kinases signaling pathways and may be used as an anti-inflammatory therapeutic material.

• Korean Journal of Clinical Pharmacy
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• v.13 no.2
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• pp.97-105
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• 2003

아스코마이신(ascomycin)의 macrolactam 유도체인 피메크로리무스(pimecrolimus; 엘리델 [Elidel], SDZ ASM 981; Novartis Pharma AG, 바젤, 스위스)는 세포선택성을 지닌 염증성 사이토카인(cytokines) 억제제로서 아토피피부염, 알레르기성 접촉피부염, 자극성 접촉피부염 및 판형 건선 등 염증성 피부질환의 치료제로 개발되었다. T세포와 비만세포의 염증성 사이토카인 생산 분비를 억제하고 사전 형성된 염증성 매개물질의 비만 세포 분비를 저해한다. 국소 투여된 피메크로리무스는 알레르기성 접촉피부염(allergic contact dermatitis [ACD]) 돼지 모델에서 고역가 코르티코스테로이드 클로베타졸-17-propionate(corticosteroid clobetasol-17-propionate)와 동등한 효과를 나타낸다. 하지만 피메크로리무스는 클로베타졸과는 달리 피부 위축을 일으키지 않는다. 경구 투여시 피메크로리무스는 마우스와 랫트 ACD 치료에 있어서 타크로림무스(tacrolimus [FK 506])와 동등한 혹은 더 우수한 효과를 나타낸다. 또한 피메크로리무스는 아토피피부염 급성 징후 유사 모델인 저마그네슘 혈증 탈모 랫트(hypomagnesemic hairless rat)의 피부 염증과 소양증을 효과적으로 감소시킨다. 피메크로리무스는 랫트에서 다음과 같은 측면의 전신 면역반응 손상 효과가 타크로리무스 와 비교하여 낮게 평가된다: (1)국소 이식편대 숙주 반응, (2)양(sheep) 적혈구에 대한 항체 형성, (3)신장이식. 시험관내 평가시 돼지 피부를 통한 피메크로리무스 투과 속도가 타크로리무스보다 10배 낮게 측정되므로 생체에서 경피 흡수가 더 적게 될 것으로 판단된다. 상기 자료로 판단컨대 피메크로 리무스는 피부에 대한 항염증 활성이 높을 뿐 아니라 전신 면역반응 손상 부작용이 낮은것으로 사료된다.

• Korean journal of food and cookery science
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• v.20 no.5
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• pp.505-510
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• 2004

이물질 침입에 대한 인식의 결과 NO, PGE$_2$, TNF-, IL-6와 같은 여러 신호전달물질의 분비가 개시되며 이들을 억제하는 물질을 항염증제라고 볼 수 있다. 본 연구에서는 회향(Foeniculum vulgare Mill.) 열매 추출물이 mouse macrophages RAW264.7 세포에서 lipopolysaccharide(LPS)로 유도한 NO(iNOS 산물), PGE$_2$(COX-2 산물) 및 cytokines (TNF-$\alpha$, IL-6) 생성 억제에 미치는 영향을 살펴보았다. 회향 열매의 methanol 추출물 및 분획물(chloroform, butanol, and aqueous fractions)은 4～100$\mu$g/mL 농도에서 LPS가 활성화된 대식 세포에서 NO 생성을 억제하였으며 독성을 나타내지 않았다. LPS가 유도한 PGE$_2$ 생성은 butanol 분획(100 $\mu$g/mL)에 의해서만 유의적으로 감소하였다(P<0.05). 회향 열매 추출물 및 분획물은 TNF-$\alpha$의 생성을 유의적으로 감소시켰으며 IL-6의 생성은 methanol extract(4～100 $\mu$g/mL), chloroform fraction(4 $\mu$g/mL), butanol fraction(4 and 100$\mu$g/mL) 및 aqueous fraction(4～100 $\mu$g/mL)에 의해 감소되었다(P<0.05). 이는 회향 열매 추출물은 염증 상태에서 유용할 것이며 COX-2와 iNOS를 억제하는 butanol 분획은 새로운 항염증제 개발에 사용될 수 있음을 시사하여 주었다.

• Journal of Oriental Neuropsychiatry
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• v.19 no.2
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• pp.209-221
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• 2008

목적 : 구절초는 국화과에 속하는 다년생 초본으로 가을에 줄기와 잎을 가을에 채취한 것을 한약재로 사용하여 대한, 월경불순 등 각종 여성질환과 함께 위냉증, 소화불량, 감고, 폐렴, 기관지염, 배뇨장애 및 신경퇴행성 질환에 활용되고 있다. 본 연구에서는 LPS로 염증유도된 대식세 포주를 활용하여 구절초의 항염증효능을 확인하고자 하였다. 방법 : 구절초 추출물의 항염증효과를 관찰하기 위하여 RAW264.7 대식세포주에서 MTT cytotoxic assay, iNOS 및 COX-2 발현, NO와 PGE2 생성 및 $NF-{\kappa}B$ 활성실험을 수행하였다. 결과 : 세포독성실험을 통하여 구절초 추출물의 안전성이 확인되었으며 LPS로 염증유도된 RAW264.7 대식세포주에서 증가된 iNOS의 발현이 감소되었음을 확인하였다. 또한 NO 및 PGE2의 생성을 억제하였다. 이러한 결과는 구절초가 염증매개물질의 생성을 억제하는 효과가 있음을 확인할 수 있었으며, $NF-{\kappa}B$ 활성도를 감소시킴을 관찰하였다. 결론 : 이러한 결과는 구절초가 $NF-{\kappa}B$ pathway를 조절해 줌으로써 항염증효과를 나타내는 것으로 사료된다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.4
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• pp.572-582
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• 2001

A method of metal-hydride thermal conversion that is an alternative to the traditional method is proposed and investigated. The unit heat pump consists of reactors of two different metal-hydrides are distributed inside parallel channels filled with porous media. The channels are blown through with a heat-transfer agent. Thermal conversion develops as a set of successive heat waves. By a numerical-modeling method it is shown that the maximum thermal effect is attained in synchronous motion of the heat wave and the heat source (or sink) that accompanies the phase transition in the succession of unit metal-hydride pumps. The results are presented in a form convenient for prediction of the thermal and energy efficiency of the proposed thermal-conversion method in real devices.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2006.06a
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• pp.49-52
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• 2006

오늘날 컴퓨터의 발달과 인터넷의 확산으로 멀티미디어 컨텐츠의 보급이 급격히 확대되고 있으며, 이들 컨텐츠에는 원거리 화상회의, 감시시스템, 주문형 비디오(VOD), 주문형 뉴스(NOD), 디지털 편집 시스템 등 동영상이 포함되어 있다. 이처럼 동영상은 정보교환과 정보표현의 매개물로서 중요한 역할을 한다. 그러나 이와 같은 동영상은 노이즈나 전송과정 중 발생하는 문제 등으로 인해 항상 좋은 품질을 보장되지 않는다. 이런 훼손된 영상을 원영상으로 복원하거나 사용자가 제거 혹은 복원하고자 하는 영역을 지정 처리함으로서 다양한 정보를 획득할 수 있다. 일반적으로 pc에서 사용되어지는 대부분의 동영상은 $15fps{\sim}30fps$이다. 대부분의 동영상 편집 기술은 각각의 frame을 추출하여 수동적으로 처리하므로 비용과 시간이 많이 든다. 이런 단점을 해결하기 위해 여러 방법이 기존에 시도되고 있다. 제거 혹은 복원하고자 하는 영역을 전 frame에서 처리하기 위해 움직임 검출 및 추적기법이 사용되며, 제거 혹은 복원하기 위해 median filtering, image inpainting 처리 방법들이 있다. 본 연구에서는 사용자에 의해 미리 정의된 바운딩 박스내의 객체를 추적하여 객체의 중심값을 찾는 mean-shift algorithm을 이용하여 움직이는 객체를 추적하였고 image Inpainting algorithm을 이용하여 훼손된 영역을 복원하거나 제거하고자 하는 객체를 제거하였다.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.1
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• pp.15-19
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• 2004

Ant Colony System(ACS) is a meta heuristic approach based on biology in order to solve combinatorial optimization problem. It is based on the tracing action of real ants which accumulate pheromone on the passed path and uses as communication medium. In order to search the optimal path, ACS requires to explore various edges. In existing ACS, the local updating rule assigns the same pheromone to visited edge. In this paper, our local updating rule gives the pheromone according to the number of visiting times and the distance between visited cities. Our approach can have less local optima than existing ACS and find better solution by taking advantage of more informations during searching.