• Journal of Pharmacopuncture
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• v.26 no.3
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• pp.257-264
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• 2023

Objectives: The study was designed to evaluate anti-arthritic activity of Ajmodadi Churna (AC) and its effect on Complete freund's adjuvant (CFA)-induced arthritis in Wistar rats. Methods: Arthritis was induced by injecting 0.2 mL CFA into sub plantar surface of left hind paw. Test sample AC-1 and AC-2, 200 and 400 mg/kg, respectively was given to the animals for 21 consecutive days. The increase in swelling was observed after induction of arthritis. The paw edema was measured on 0, 3, 7, 14 and 21 day using Vernier caliper after the induction of arthritis. The collected blood samples further used for the estimation of red blood cells (RBC), white blood cells (WBC), erythrocytes sedimentation rate (ESR), and hemoglobin (Hb), using hematology analyzer. Serum concentration of IL-6 and TNF-α were also measured using rat ELISA kits. Results: Results showed that a significant reduction in paw edema was observed in AC-2 treated rats. The paw edema was restored on day 21 was 4.48 mm for AC-2, which is near to the control group. The arthritis score in treated rats was found to be considerably lower than in the control group i.e. 0.83 for AC-2 and 1.50 for AC-1. A decrease in levels of RBC and hemoglobin were observed in arthritic rats. Inflammation was significantly reduced and serum levels of IL-6 and TNF-α were lowered after treatment with the test drug. Conclusion: It can be concluded from the study that AC possess significant anti-arthritic activity. Furthermore, this condition was linked to a reduction in abnormal humoral immune responses.

• Journal of Ocean Engineering and Technology
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• v.22 no.5
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• pp.106-111
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• 2008

In this paper, study about property evaluation for the metal matrix composites fabricated by low pressure infiltration process. Aluminum alloy composite which is reinforced by Metal fiber preform was fabricated by low pressure casting process. Infiltration condition was changed the pressure infiltration time of 1 sec, 2 sec and 5 sec under a constant pressure of 0.4 MPa. The molten alloy completely infiltrated the FeCrSi metal perform regardless of the increase in the pressure acceleration time. The the porosity in the FeCrSi/AC8A composite was investigated. The porosity was reduced as the pressure acceleration time as shorter. The FeCrSi/AC8A composite was investigated the wear test for to know the relationship between Porosity and wear resistance. FeCrSi/AC8A composite at pressure acceleration time of 1sec is shown excellent wear resistance.

• Journal of the Korean Society of Visualization
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• v.11 no.1
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• pp.48-52
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• 2013

This paper presents experimental observation of asymmetric electrohydrodynamic flow generated around a pair of symmetric coplanar electrodes. Electrodes are attached on the bottom of the cavity containing a dielectric liquid, i.e., a mixture of dodecane and 0.5% wt Span80. In the first experiment, an AC voltage of 1500 V is applied with the frequency varying in the range 10~500 hz and the left electrode being grounded. The flow patterns show that the center line of vortices is unexpectedly tilted to the left side. If the right side electrode is grounded, the center line is tilted to the right side. The magnitude of the fluid velocity shows an irregular variation with the frequency in the range 10 Hz~100 Hz, beyond which it simply decays. In the second experiment, we applied fixed AC with 1000 V and 60 Hz superposed by DC voltage varying in the range -1000 V ~ +1000 V. The center line of the flow pattern is tilted to the right side with positive DC voltage and to the left side with negative DC. We have managed to show that the flow pattern can be symmetric with a suitable combination of DC and AC, e.g., DC 850 V plus AC 1000 V with the frequency 10 Hz.

• The Transactions of the Korean Institute of Power Electronics
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• v.28 no.1
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• pp.68-75
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• 2023

This paper proposes a three-phase single-stage AC-DC converter for the small wind generation system. Input power factor improvement and insulated output can be implemented with the proposed three-phase single-stage AC-DC converter under the wide power generation voltage (80-260 V_ac) and frequency (10-42 Hz) in a small wind power generation (WPG) system. The proposed converter is also capable of zero-voltage switching in the primary-side switches and zero-current switching in the secondary-side diodes by phase-shift control at a fixed switching frequency. In addition, it is possible to control a wide output voltage (V_o: 39 V_DC-60 V_DC) by varying the link voltage and improving the input power factor (PF) and the total harmonic distortion factor (THD_i). Simulation and experimental results verified the validity of the proposed converter.

• Applied Chemistry for Engineering
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• v.9 no.6
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• pp.835-841
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• 1998

This study was devoted to the manufacturing process of activated carbon(AC) using and anthracite and bituminous coals which were regarded as appropriate for AC manufacturing, and the physcial properties a AC prepared with coal blends were characterized by the ultimate and proximate analysis. Generally, as the fraction of antheracite in AC from anthracite and bituminous coal blends was increased, AC yield was increased whereas iodine value($I_2$) was decreased. Being not related to mixing ratio of coal blends, the apparent density of AC remained constant. Pore development and iodine value of AC based on coal blends(Fushun and Dandong, 75:25 wt. %) were examined, varing carbonization and steam activation conditions. These results showed that the average pore diameter of AC was below $20{\AA}$ in the activation temperature range of 850 to $900^{\circ}C$ and the iodine value was above $1000m^2/g$. When the adsorption capacity of manufactured AC was compared with commercial AC, it is found that the AC from coal blends was comparable to the commercial AC. Therefore, it was confirmed that the characteristics of manufactured AC were changed with manufacturing conditions and the ratios and types of coal blends.

• Progress in Superconductivity and Cryogenics
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• v.16 no.2
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• pp.1-6
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• 2014

The five-year national project in Japan for R&D of coated conductors and applications, named as the Materials and Power Applications of Coated Conductors (M-PACC) project, was finished at the end of FY2013. The project consists of four sub-themes as cable, transformer, SMES and coated conductors. In the theme of coated conductors, the fabrication process had been developed to satisfy the requirements from the applications such as in-field $I_c$ performance, low AC loss in the long tapes etc. Through the project, the remarkable progress was achieved as follows; a high in-field minimum $I_c$ value over 54A/cm-width under 3T at 77K was realized in a 200m long EuBCO tape with artificial pinning centers of $BaHfO_3$ by the pulsed laser deposition (PLD) technique on the IBAD template. On the other hand, the AC loss reduction was confirmed in the tapes fabricated by both PLD and the metal organic deposition (MOD) techniques by scribing 100m tapes into 10-filamments. Additionally, the mechanism of the delamination phenomenon was systematically investigated and the strength was improved by eliminating the origins of the weak points in the films. Through the development, all targeted goals were accomplished and the several results were appreciated as a world champion data.

• Journal of the Korean Magnetics Society
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• v.22 no.1
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• pp.23-26
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• 2012

New digital feedback algorithm was developed to measure iron loss of soft magnetic materials under a condition of sinusoidal flux waveform. $V_{in}$(B) curve was used instead of H(B) curve to decide next input waveform in the feedback module so that adjusting phases of current waveform, flux waveform, and input waveform could be removed. The effectiveness of the developed algorithm was verified when iron loss of ferrite cores was measured under frequencies of 1 and 10 kHz.

• International Journal of Control, Automation, and Systems
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• v.3 no.4
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• pp.620-630
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• 2005

This paper presents a digital controller for a single phase UPS inverter under two main considerations: (i) the overall system shall keep very low AC-voltage tracking error as well as no phase delay over different load conditions, and (ii) the digital controller shall be employed at a fixed sampling time. We propose that the former can be achieved by the proposed controller using the error-state approach and the latter can be dealt with by the socalled characteristics ration assignment.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.195-198
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• 2000

In this paper the insulation characteristics test results of 25 low-voltage induction motors($3\phi$, 5HP, 380V) are presented. Five different types of insulation techniques are applied to 25 motors. The maximum partial discharge (PD) magnitude ($\textrm{Q}_{m}$) discharge inception voltage (DIV) dissipation factor tip-up ($\Delta$tan$\delta$) and rate of change in AC current($\Delta$I) are measured by PD and AC current tests. Also the insulation breakdown tests by high voltage pulse are performed and the corresponding breakdown voltage are obtained.

• Proceedings of the KIPE Conference
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• 2012.11a
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• pp.35-36
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• 2012