• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.8
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• pp.1153-1163
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• 2002

A transient analysis on temperatures of fuel and oil in hydraulic and lubrication systems in an aircraft was studied using the finite difference method. Numerical calculation was performed by an explicit method with modified Dufort-Frankel scheme. Among various missions, air superiority mission was considered as a mission model with 20% hot day ambient condition in subsonic region. The ambience of the aircraft was assumed as turbulent flow. Convective heat transfer coefficient were used in calculating heat transfer between the aircraft surface and the ambience. For an aircraft on the ground, an empirical equation represented as a function of free-stream air velocity was used. And the heat transfer coefficient for flat plate turbulent flow suggested by Eckert was employed for in-flight phases. The governing equations used in this analysis are the mass and energy conservation equations on fuel and oils. Here, analysis of fuel and oil temperature in the engine was not carried out. As a result of this analysis, the ground operation phase has shown the highest temperature and the largest rate of temperature increase among overall mission phases. Also, it is shown that fuel flow rate through fuel/oil heat exchanger plays an important role in temperature change of fuel and oil. This analysis could be an important part of studies to ensure thermal stability of the aircraft and can be applicable to thermal design of the aircraft fuel system.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.11
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• pp.1055-1063
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• 2012

Fluctuating wall pressures were measured using an array of 16 piezoelectric transducers beneath a turbulent boundary layer. The coating used in this experiment was an open-cell, urethane-type foam with a porosity of approximately 50 ppi. The ultimate objective of the coating is to provide a mechanical filter to reduce the wall pressure fluctuations. The boundary layer on the flat plate was measured by using a hot wire probe, and the CPM method was used to determine the skin friction coefficient. The wall pressure autospectra and streamwise wavenumber-frequency spectra were compared to assess the attenuation of the wall pressure field by the coating. The coating is shown to attenuate the convective wall pressure energy. However, the relatively rough surface of the coating in this investigation resulted in a higher mean wall shear stress, thicker boundary layer, and higher low-frequency wall pressure spectral levels compared to a smooth wall.

• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.117-124
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• 1997

The analgesic effects of DA-5018, a new caosaucin derivative, were evaluated in various experimental pain models. Drugs were administered subcutaneously or topically. When drugs were administered subcutaneously, 1) the $ED_{50}$ of DA-5018, morphine . HCI, capsaicin and acetaminophen were 0.091-2.0, 0.3-4.3, 1.4-26.5 and 45.4-643 mg/kg, respectively in various pain or inflammatory models including acetic acid writhing, formalin, tail flick, Randall-Selitto, hot plate and crouton oil-induced ear edema test, 2) the AD2 values (the dose for doubling of pain threshold of vehicle control) of DA-5018, capsaicin and ketoprpgin were 1.07 $\pm$ 0. 18, 23.47$\pm$4.46 and 2.97$\pm$0.43 mg/kg in Freund's complete adjuvant (FCA)-induced arthritic pain model. And by topical application, 1) neither DA-5018 0.3% cream nor Zostrix-HP (capsaicin 0.075%) were effective in formalin test, 2) although DA-5018 0.3% cream significantly inhibited the croton oil-induced ear edema being better than Zostrix-HP and Kenofen (ketoprofen 3%). 3) In FCA model, DA-5018 0.3% cream reversed the decreased pain threshold of arthritic rat from 136.4 g (day 0) to 289.0 g (day 5) and 250.1 g (day 10), which was similar to Zostrix-HP. These results suggest that DA-5018 administered subcutaneously has a potent and broad analgesic spectrum than nonsteroidal antiinflammatory drugs against acute and chronic pain, and by topical application it exerts comparable analgesic and antiinglammaatory effects to capsaicin cream.

• Korean Journal of Medicinal Crop Science
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• v.18 no.4
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• pp.238-243
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• 2010

In the present study, the antinociceptive profiles of Viola tricolor L. (V. tricolor L.) extract were examined in ICR mice. V. tricolor L. extract administered orally (200mg/kg) showed an antinociceptive effect as measured by the tail-flick and hot-plate tests. In addition, V. tricolor L. extract attenuated the writhing numbers in the acetic acid-induced writhing test. Furthermore, the cumulative nociceptive response time for intrathecal (i.t.) injection of substance P (0.7 ${\mu}g$) was diminished by V. tricolor L. extract. Intraperitoneal (i.p.) pretreatment with yohimbine (${\alpha}_2$-adrenergic receptor antagonist) attenuated antinociceptive effect induced by V. tricolor L. extract in the writhing test. However, naloxone (opioid receptor antagonist) or methysergide (5-HT serotonergic receptor antagonist) did not affect antinociception induced by V. tricolor L. extract in the writhing test. Our results suggest that V. tricolor L. extract shows an antinociceptive property in various pain models. Furthermore, this antinociceptive effect of V. tricolor L. extract may be mediated by ${\alpha}_2$-adrenergic receptor, but not opioidergic and serotonergic receptors.

• Journal of the Korean Society of Physical Medicine
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• v.5 no.4
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• pp.551-558
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• 2010

연구목적 : 미세전류 자극이 아주반트로 류마티스 관절염을 유발한 실험동물의 염증반응과 통증에 미치는 효과를 알아보기 위하여 실험동물의 발허리발가락관절내 염증반응 정도를 나타내는 인터루킨-6(interleukin-6)의 발현과 핫플레이트(hot plate)를 이용한 발도피지연시를 측정하여 미세전류의 효과에 대하여 알아보고자 하는데 목적이 있다. 연구방법 : 실험동물은 무작위로 대조군(n=18)과 미세전류를 적용한 실험군(n=18)으로 구분하였고, 각 군당 6마리씩 1일군, 7일군, 14일군으로 배정하였다. 류마티스 관절염 유발후 1일, 7일, 14일에 모든 실험동물의 열통각 역치를 나타내는 발도피지연시와 발허리발가락관절내 인터루킨-6의 발현정도를 측정하였다. 각 집단 내의 기간에 따른 발도피지연시와 인터루킨-6의 면역반응성은 일원배치 분산분석을 실시하였고, 사후분석으로는 Duncan의 다중범위검정을 실시하였다. 실험군과 대조군을 비교하기 위하여 독립표본 t-test를 실시하였다. 연구결과 : 실험결과는 다음과 같다. 1) 아주반트 주사 1일후, 실험군과 대조군에서 인터루킨-6 면역반응성과 발도피지연시는 비슷한 양상을 보였다. 2) 인터루킨-6 면역반응성은 아주반트 주사 7일, 14일 후 대조군이 실험군보다 유의하게 증가되었다(p<.05). 3) 발도피지연시는 아주반트 주사 7일, 14일 후 실험군이 대조군보다 유의하게 증가되었다(p<.05). 결론 : 이상의 결과로부터, 미세전류 자극이 아주반트로 유발된 류마티스관절염 모델에서 활액 조직내 염증반응을 감소시키고 열통각역치는 증가되는 것을 알 수 있었다.

• The Journal of Internal Korean Medicine
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• v.18 no.1
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• pp.69-85
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• 1997

This study was designed to elucidate the anti-inflammatory, cardiovascular, anti-thrombotic and analgesic effects of Shintongchugeotang. The anti-inflammatory effect was measured by the method of carragenin induced edema, protein leakage test using CMC-pouch, and the analgesic effect was measured by the acetic acid method and hot plate method, and the effect of Shintongchugeotang on the cardiovascular system was observed by the change of flow rate of Ringer solution in the vascular system in the ear of rabbit, and the contraction and dilatation of rat tail artery. Death rate, platelet aggregation, plasma coagulation activity was observed for the measurement of the anti-coagurative effect of Shintongchugeotang. The result was as follows : 1. After the administration of Shintongchugeotang extract, Carragenin induced edema and CMC-pouch protein leakage were significantly decreased. 2. The slight analgesic effect of Shintongchugeotang extract was confirmed by the observation of writhing syndrome, paw licking time, and escape time. 3. The drug increased the auricular blood flow in rabbit. 4. The drug relaxed the artery contraction by pretreated norepinephrine in rat. 5. The drug inhibited the death rate of mouse which was led to thromboembolism by serotonin and collagen. 6. The drug inhibited the platelet aggregation in rat. 7. The drug prolonged the prothrombin time and activated partial thromboplastin time on the test of plasma coagulation factor activity in rat, but was not valuable.

• Advances in Traditional Medicine
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• v.8 no.2
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• pp.196-203
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• 2008

The methanol extract of the root of Artanema sesamoides Family Scrophuilariaceae (MEAS) was investigated for possible analgesic and anti-inflammatory effects in animals. Three models were used to study the extract effects on nociception, which were acetic acid-induced writhing response, hot-plate method and the tail flick test in mice. The antiinflammatory effects were evaluated using carrageenan, dextran, histamine and serotonin induced rat paw oedema (acute) and cotton pellet induced granuloma (chronic) models in rats. Results of the study revealed that the extract exhibited significant (P < 0.001) analgesic effect at a dose of 50, 100 and 200 mg/kg b.w p.o in mice in all the models. In acute model, the MEAS also exhibited significant (P < 0.001) antiinflammatory effect in all the above mentioned doses. In chronic model (cotton pellet induced granuloma) the MEAS 200 mg/kg and indomethacin 10 mg/kg showed that inhibition of granuloma formation 25.0% and 47.7% respectively (P < 0.001). The MEAS and indomethacin were effectively preventing the transudation of the fluid. Thus, the present study revealed that the methanol extract of the root of Artanema sesamoides exhibited significant analgesic and antiinflammatory activity.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.235-235
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• 1996

1. 초산 writhing법에서 DA-5018, morphine, capsaicin 및 acetaminophen의 E $D_{50}$ 은 각각 0.1, 0.3, 1.4 및 45.4 mg/kg이었으며, formalin법에서 DA-5018과 morphine의 E $D_{50}$은 0.17과 4.3 mg/kg이었다. Randall-Selitto법에서 DA-5018, morphine, capsaicin 및 acetaminophen의 E $D_{50}$은 0.66, 3.9, 4.2 및 643 mg/kg이었다. Tail flick법에서 DA-5018, morphine 및 capsaicin의 E $D_{50}$ 은 2.0, 2.6 및 14.2 mg/kg이었고 hot plate법에서 DA-5018과 capsaicin의 E $D_{50}$은 1.7 및 26.5mg/kg이었다. 그러나 열자극에 의한 동통모델에서 acetaminophen은 진통효과가 없었다. 2. Streptozotocin유발 당뇨랫드에 DA-5018 0.2, 0.5 및 1.0mg/kg 또는 capsaicin 10 mg/kg 투여시 1, 3, 7 일째에서 각각 유의성있는 동통역치의 증가를 나타내었으나 ketoprofen(10 mg/kg) 및 desipramin(10 mg/kg) 투여시는 동통역치의 유의성있는 증가가 나타내지 않았다. 관절염 동통모델에서 DA-5018, ketoprofen 및 capsaicin을 투여한 후 7일째에 동통역치를 2배 증가시키는 용량은 각각 0.66, 3.76 및 17.38 mg/kg이었다. 3. 이상의 결과로부터 DA-5018은 morphine 및 capsaicin에 비해 동등 이상의 효력을 갖고 있으며, 비스테로이드성 진통제보다 효능이 우수함을 확인하였다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.2
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• pp.101-105
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• 2010

We fabricated FEDs(Filed emission devices) based on ZnO nanowires. The ZnO nanowires were synthesized on Au thin films by hydrothermal method at the temperature of 90[$^{\circ}C$] on hot plate. In order to form tips of the ZnO nanowire, SDS(Sodium Dodecyl Sulfate) was mixed in O.05-0.3[wt%] solution as capping material. After 2 hour growth, we obtained nanowires of chain form The high-purity nanowires showed sharp tip geometry with a wurtzite structure. The field emission properties of the ZnO nanowires were investigated in high vacuum chamber. The turn-on field for the ZnO nanowires was found to be about 4.1[V/${\mu}m$] at a current density of 0.1[${\mu}A/cm^2$].

• The Journal of Korean Physical Therapy
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• v.9 no.1
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• pp.89-96
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• 1997

The purpose of this study was to determine the effect of Ga-Al-As (Gallium-Aluminum-Arsenid) laser radiation on the tail-flick latency in rat. Thirty Sprague-Dawley male and female rats Were divided into five groups : that is control, laser 15sec radiation, laser 30sec radiation, laser 60sec radiation, and Tramadol Hcl injection groups. The continuous Ga-Al-As laser with, wave length 780-830nm and diameter of probe in the 3mm, averse output of 100mw radiation was applied to the meridian point(Gv 1 : Governing vessel) of the rats. Tail-flick latency were measured with hot plate at $55^{\circ}C$ : before treatment and immediately, 30 minutes, 1 hour, 2 hours, 24 hours, 24 hours and 48 hours after treatment. The result were as follows ; 1. The tail-flick latency according to time varition, control group was not significance. 2. The tail-flick latency according to time varition, laser 15 sec irradiate rats in post-treared was significance(P<0.05). 3. The tail-flick latency according to time varition, laser 30 sec irradiate rats group was not significance. 4. The tail-flick latency according to time varition, laser 60 sec irradiate rats in post 30 minute was significance(P<0.05). 5. The tail-flick latency according to time varition, Tramadol Hcl injection rats in post-treated (P<0.05), post 30 minute(P<0.05), post 60 minute (P<0.01) and 2 hour(P<0.05) was significance. This study suggest that Ga-Al-As (Gallium-Aluminum-Arsenid) laser applied to meridian point of the rat with 15 sec, 30 sec, and 60 set radiation could induc no analgesic effect, but Tramadol Hcl injection rat is good analgesic effect.