• Advances in Traditional Medicine
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• v.6 no.4
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• pp.349-354
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• 2006

In the present study, three Malaysian Channa spp. fish Channa striatus, Channa micropeltes and Channa lucius were assessed for their analgesic activity. Distilled water and mixture of chloroform: methanol were used for extraction. The analgesic or antinociceptive activity was investigated by abdominal writhing and hot plate test. The water extract of Channa striatus and the chloroform: methanol extract Channa lucius produced potent antinociceptive effect when assessed with the abdominal writhing test. The activity was compared to morphine where the activity of the extracts was less potent than the opioid. In the hote plate test, water extract of Channa striatus revealed significant activity and chloroform:methanol extract of Channa micropeltes had moderate activity. However, these activities were statistically lower than morphine. Collectively, this study also showed that Channa striatus extract was more potent analgesic agent when compared to the other closely related snakehead Channa micropeltes and Channa lucius.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1995.04a
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• pp.196-201
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• 1995

The broadband and discrete sources of sound in small cooling fans of propeller type and centrifugal type were investigated to understand the turbulent vortex structures from many bladed fans using ANSI test plenum for small air-moving devices (AMDs). The noise measurement method uses the plenum as a test apparatus to determine the acoustic source spectral density function at each operating conditions similar to real engineering applications based on acoustic similarity laws. The characteristics of fans including the head rise vs. volumetric flow rate performance were measured using a performance test facility. The sound power spectrum is decomposed into two non-dimensional functions: an acoustic source spectral distribution function F(St,.phi.) and an acoustic system response function G(He,.phi.) where St, He, and .phi. are the Strouhal number, the Helmholtz number, and the volumetric flow rate coefficient, respectively. The autospectra of radiated noise measurements for the fan operating at several volumetric flow rates,.phi., are analyzed using acoustical similarity. The rotating stall in the small propeller fan with a bell-mouth guided is mainly due to a leading edge separation. It creates a blockage in the passage and the reduction in the flow rate. The sound power levels with respect to the rotational speeds were measured to reveal the mechanisms of stall and/or surge for different loading conditions and geometries, for example, fans installed with a impinging plate. Lee and Meecham (1993) studied the effect of the large-scale motions like impinging normally on a flat plate using Large-Eddy Simulation(LES) and Lighthill's analogy.[ASME Winter Annual Meeting 1993, 93-WA/NCA-22]. The dipole and quadrupole sources in the fans tested are shown closely related to the vortex structures involved using cross-correlations of the hot-wire and microphone signals.

• Journal of the Korean Society for Nondestructive Testing
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• v.26 no.4
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• pp.211-219
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• 2006

The UET(ultrasound excited thermography) for the ,eat-time diagnostics of the object employs an infrared camera to image defects of the surface and subsurface which are locally heated using high-frequency putted ultrasonic excitation. The dissipation of high-power ultrasonic energy around the feces of the defects causes an increase In temperature. The defect's image appears as a hot spot (bright IR source) within a dark background field. The UET for nondestructive diagnostic and evaluation is based on the image analysis of the hot spot as a local response to ultrasonic excited heat deposition. In this paper the applicability of VET for fast imaging of defect is described. The ultrasonic energy is injected into the sample through a transducer in the vertical and horizontal directions respectively. The voltage applied to the transducer is measured by digital oscilloscope, and the waveform are compared. Measurements were performed on four kinds of materials: SUS fatigue crack specimen(thickness 14mm), PCB plate(1.8 mm), CFRP plate(3 mm) and Inconel 600 plate (1 mm). A high power ultrasonic energy with pulse durations of 250ms Is injected into the samples in the horizontal and vertical directions respectively The obtained experimental result reveals that the dissipation loss of the ultrasonic energy In the vertical injection is less than that in the horizontal direction. In the cafe or PCB, CFRP, the size of hot spot in the vortical injection if larger than that in horizontal direction. Duration time of the hot spot in the vertical direction is three times as long as that in the horizontal direction. In the case of Inconel 600 plate and SUS sample, the hot spot in the horizontal injection was detected faster than that in the vertical direction

• Korean Journal of Plant Resources
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• v.23 no.6
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• pp.513-518
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• 2010

In the present study, the antinociceptive profiles of Dianthus chinensis L extract were examined in ICR mice. Dianthus chinensis L extract administered orally (200 mg/kg) showed an antinociceptive effect as measured by the tail-flick and hot-plate tests. In addition, Dianthus chinensis 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 Dianthus chinensis L extract. Intraperitoneal (i.p.) pretreatment with yohimbine ($\alpha_2$-adrenergic receptor antagonist) attenuated antinociceptive effect induced by Dianthus chinensis L extract in the writhing test. However, naloxone (opioid receptor antagonist) or methysergide (5-HT serotonergic receptor antagonist) did not affect antinociception induced by Dianthus chinensis L extract in the writhing test. Our results suggest that Dianthus chinensis L extract shows an antinociceptive property in various pain models. Furthermore, this antinociceptive effect of Dianthus chinensis L extract may be mediated by $\alpha_2$-adrenergic receptor, but not opioidergic and serotonergic receptors.

• Steel and Composite Structures
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• v.26 no.3
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• pp.315-328
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• 2018

Built-up Double-I (BD-I) columns consist of two hot rolled IPE sections and two cover plates which are welded by fillet welds. In Iran, this type of column is commonly used in braced frames with simple connections and sometimes in low-rise Moment Resisting Frames (MRF) with Welded Flange Plate (WFP) beam-column detailing. To evaluate the seismic performance of WFP connection of I-beam to BD-I column, traditional and modified exterior MRF connections were tested subjected to cyclic prescribed loading of AISC. Test results indicate that the traditional connection does not achieve the intended behavior while the modified connection can moderately meet the requirements of MRF connection. The numerical models of the connections were developed in ABAQUS finite element software and validated with the test results. For this purpose, moment-rotation curves and failure modes of the tested connections were compared with the simulation results. Moreover to avoid improper failure modes, some improvements of the connections were evaluated through a numerical study.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.345-350
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• 2008

The present study has been conducted to develop a heat recovery system for a 1 MW class gas engine based cogeneration system. In the cogeneration system, heat is recovered from two parts, which are jacket water and exhaust gas. The heat from the jacket water is recovered by a plate type heat exchanger and used for the room heating and/or hot water supply. The heat from the exhaust gas is used to generate steam. For both of the heat recovery devices, 1/5 scaled tests are performed and the data are compared to the conventional correlations for the design.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.448-451
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• 2000

The purpose of this study is to manufacture and test a thermoelectric generator which converts unused energy from close-at-hand sources, such as garbage incineration heat and industrial exhaust, to electricity. A manufacturing process and the properties of a thermoelectric generator are discussed before simulating the thermal stress and thermal properties of a thermoelectric module located between an aluminum tube and alumina plate. We can design the thermoelectric modules having the good properties of thermoelectric generation. Resistivity of thermoelectric module for thermoelectric generation consisting of 62 cells was 0.15-0.4$\Omega$ Developed thermoelectric modules can be expected th have better properties than thermoelectric cooling modules above $70^{\circ}C$ in temperature difference between hot and cold ends.

• International Journal of Korean Welding Society
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• v.3 no.1
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• pp.8-16
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• 2003

A major concern in Gas Metal Arc (GMA) welding process is the determination of welding process variables such as wire diameter, gas flow rate, welding speed, arc current and welding voltage and their effects on the desired weld bead dimensions and shape. To successfully accomplish this objective, 81 welded samples from mild steel AS 1204 flats adopting the bead-on-plate technique were employed in the experiment. The experimental results were used to develop a mathematical model to predict the magnitude of bead geometry as follows; weld bead width, weld bead height, weld bead penetration depth, weld penetration shape factor, weld reinforcement shape factor, weld bead total area, weld bead penetration area, weld bead reinforcement area, weld bead dilution, length of weld bead penetration boundary and length of weld bead reinforcement boundary, and to establish the relationships between weld process parameters and bead geomery. Multiple regression analysis was employed for investigating and modeling the GMA process and significance test techniques were applied for the interpretation of the experimental data.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.189-193
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• 2011

To investigate the physiological activities of hot water extract and solvent fractions isolated from Pleurotus ferulea, antioxidative, fibrinolytic, thrombin inhibitory, and ${\alpha}$-glucosidase inhibitory activities were examined. Pleurotus ferulea, hot water extract was fractionated into hexane, chloroform, ethyl acetate, butanol and water fraction. Each of these was assayed individually. The antioxidative activities of ethyl acetate and butanol fractions were 86.79% and 87.82%, respectively. Using the fibrin plate method, only the ethyl acetate fraction showed a plasmin activity of 0.08 units/ml. Thrombin inhibitory activities of chloroform and ethyl acetate fractions were 74.90% and 71.08%, respectively. In the ${\alpha}$-glucosidase inhibitory activity test, butanol fraction showed the highest activity at 49.67%. From the above results, we anticipate that solvent fractions of Pleurotus ferulea can be used as a materials for the development of biofunctional foods for cardiovascular diseases.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.4
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• pp.527-537
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• 1997

This study was performed to determine the effects of antimutagenicity of Porturaca oleracea L. in Korea. In Ames test, the ethanol extract of Poturaca oleracea L. inhibited mutagenic activity of N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), , 4-nitroquinoline-1-oxide(4NQO), benzo($\alpha$)pyrene (B($\alpha$)P) and 3-amino-1,4-dimethyl-5H-pyrido-(4,3-b)indole (Trp-P-1) in Salmonella typhimurium TA98 and TA100. But hot-water extract Poturaca oleracea L. only Inhibited mutagenic activity of MNNG in Salmonella typhimurium TA100, On 4NQO, the ethanol extract 100-1,600$\mu\textrm{g}$/plate of Porturaca oleracea L. showed a slight inhibitory effect of 13-48%, 4-47% in TA98 and TA100, respectively, but on MNNG, it showed higher inhibitory effect of 6-86% in TA100, And the treatment of 1,600$\mu\textrm{g}$/plate of ethanol extract of Porturacea L. had strong antimutagenicity with 74-87% inhibition against TA98 and TA100 induced by B(a)P and with 85-93% inhibition against TA98 and TA100 induced by Trp-P-1. The ethanol extract was fractionated with ether. chloroform, ethylacetate, butanol and water. Among them, most of the fraction except water fraction showed strong antimutagenicity effects against mutation induced by 4-NQO, MNNG, B(a)P and Trp-P-1. Chloroform fraction had strong antimutagenicity with 91% inhibition against TA100 induced by MNNG, diethyl etherfraction had strong antimutagenicity with 92%, 98% inhibition against TA98 and TA100 induced by 4NQO, Chloroform fraction had strong antimutagenicity with 97% inhibition against TA100 induced by B (a)P and diethyl etherfraction had strong antimutagenicity with 98% inhibition against both strain Induced by Trp-P-1, respectively.