• Toxicological Research
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• v.34 no.2
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• pp.97-102
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• 2018

The objective of this study was to determine the oral wound healing effects of acai berry water extracts (ABWE) in rat oral mucosa. To estimate the anti-oxidative effects of ABWE, the contents of phenolic compounds, and DPPH (1,1-diphenyl-2-picryl hydrazyl) and ABTS (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) abilities were evaluated. Wound healing effects of ABWE were tested following 6-day exposure after induction of wound by applying 50% acetic acid to oral mucosa of Sprague-Dawley rats. Macroscopic and histopathological analyses were performed to determine wound healing effects of ABWE. Sodium fusidate (20 mg/g) was used as positive control. ABWE showed significantly high antioxidant effects in all assays, although its potency was weaker than the positive control. From day 3 after treatment, wound healing effects of ABWE were observed in oral mucosa. These wound healing effects were also consistent with histopathological evaluation results. Taken together, these results indicate that ABWE might have potential as an oral wound healing agent in the future.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.33 no.12
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• pp.480-484
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• 1984

A speed control system of multiple induction motors is presented in this paper. The system consists of a single CSI, several wound retor type induction motors, and the choppers which control the rotor current of motors. Some performance characteristics are studied, and the closed control loop is suggested.

• The Korean Journal of Mycology
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• v.26 no.3 s.86
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• pp.314-320
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• 1998

A 0.4 kb cDNA fragment was isolated from mRNA of UV or mechanical wound damaged Pleurotus sajor-caju by the differential display method. Expression of the gene corresponding to this cDNA fragment was highly induced by mechanical wound damage or UV treatment. This gene showed only basal level expression in mycelia, stipe, and cap under normal growth conditions. Sequencing analysis showed that this cDNA fragment contains partial open reading frame. Homology search using genbank database revealed that although this gene do not have homology with already reported wound induced genes, it has a significant sequence homology in defined region with the cdc2-related protein kinase gene which is known to be involved in negative regulation of meiotic maturation in Xenopus oocytes.

• Physical Therapy Rehabilitation Science
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• v.6 no.4
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• pp.170-175
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• 2017

Objective: The anti-inflammatory effects of low-level laser in burn wound model in rats were investigated. Design: Randomized controlled trial. Methods: The rats were assigned to three experimental groups. Group I received second-degree burn wounds; Group II received dressing film and low-level laser ($1.2J/cm^2$) treatment after a burn wound; Group III received dressing film and low-level laser ($2.3J/cm^2$) treatment after a burn wound. After inducing a deep second-degree burn wound, the wound was observed every day and the burn area diameter and retraction quantification at 1, 7, and 14 days were evaluated. Low-level laser was investigated on hematological parameters after 14 days. Effects of low-level laser on the inflammatory cytokines (tumor necrosis $factor-{\alpha}$ [$TNF-{\alpha}$] and interleukin-6 [IL-6]) concentrations in the serum were evaluated using immunosorbent assay kits. Results: Group III showed a significant difference in wound size on days 7 and 14 compared to Group I (p<0.05). Group II showed a significant difference in wound size on day 14 compared to Group I (p<0.05). For wound contraction percentage, both laser therapy treatment groups showed a significant difference compared with Group I (p<0.05). There was also a significant difference in wound contraction percentage in Group III compared to Group II (p<0.05). Compared with the model control group, decreased $TNF-{\alpha}$ and IL-6 levels in the serum was observed at 14 days after burn wound induction. Conclusions: The results of this study suggest that low-level laser therapy can assist in burn wound healing, which might be associated with decreased concentrations of $TNF-{\alpha}$ and IL-6 related proinflammatory cytokines.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.33 no.8
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• pp.316-324
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• 1984

In the wound rotor induction motor, the external resistor is usually added to the rotor circuit in order to limit the starting current. In this scheme, whilst the starting current is limited, the available torque is remarkably reduced. In this paper, to improve the starting characteristics the stator current can be maintained constant by adjusting the external resistor. To change the external resistor, teh chopper and the resistor is connected in parallel, and the chopper duty cycle is adjusted by microprocessor. The duty cycle is calculated according to the actual speed of motor by microprocessor look-up table map. In this suggested scheme, the starting characteristics are remarkably improved without over-current. The starting time of this system is reduced by 20-48 Percent compared with fixed extemal resistance system in the same load.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.137-142
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• 1998

This paper describes a simple vector control scheme for the wound rotor type induction motors(WRIM) without the additional speed sensor in order to remove the external resistor bank which is usually adapted for the WRIM speed control. The motor angular speed is obtained indirectly from the slip angular speed is obtained indirectly from the slip angular speed and the slip angular speed is estimated by detecting the rotor currents only. Because the motor parameters are not included in the estimation algorithm, the proposed algorithm is free from the variation of the motor parameters and the robust sensorless vector control can be achieved. The performance of the proposed scheme is verified through the digital simulation.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.867-869
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• 2000

This paper describes the steady state performance of a self-excited wound type induction generator with stator and rotor windings connected in series along with excitation capacitors. For this purpose a mathematical model is developed by means of the well known generalized machine theory utilizing d-q axis orthogonal transformation. This model can be used to analyze short shunt and long shunt generators as well as shunt generator and the algorithm for this analysis is persented. The characteristics of generators are compared one another by using parameters which are validated by Mostafa et al.

• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.419-422
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• 1998

This paper presents how to design speed control of wound rotor induction motors with slip energy recovery. The speed is limited at some range of sub-synchronous speed of the rotating magnetic field. The problem with speed control by adjusting resistance value in the rotor circuit reduces the efficiency of power, because of the slip energy is lost when it passes through the rotor resistance. The control system is designed to maintain efficiency of motor, where it recovers loss energy by returning it to the system to improve the efficiency. A new PI control method of adaptive control [1］,［13］is applied for the system with cascade type PI controller on the main loop to keep the speed constant and the internal loop to adjust the rotor appropriated current of the load provides the good transient response without overshoot.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.256-259
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• 2001

An increase of pulsed power demand and load variation produce bad effect to power system. This causes power factor decrease. This paper proposes the excitation of the secondary side of wound rotor induction machine as one of harmonic compensation systems. In this paper, a harmonic compensation scheme based on stator flux-oriented vector control is proposed. By using the flux-oriented vector control, a voltage source PWM(Pulse Width Modulation) control scheme can be applied with fast dynamic response time. The designed control scheme is verified through simulation.

• Journal of Power Electronics
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• v.9 no.4
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• pp.575-581
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• 2009

In this paper two modes of operating a wound rotor induction machine as a generator at sub-and super-synchronous speeds in wind energy conversion systems are investigated. In the first mode, known as double fed induction generator (DFIG), the rotor circuit is fed from the ac mains via a controlled rectifier and a forced commutated inverter. Adjusting the applied rotor voltage magnitude and phase leads to machine operation as a generator at sub-synchronous speeds. In the second mode, the machine is operated in a slip recovery scheme where the slip energy is fed back to the ac mains via a rectifier and line commutated inverter. This mode is described as double output induction generator (DOIG) leading to increase the efficiency of the wind-to electrical energy conversion system. Simulated results of both modes are presented. Experimental verification of the simulated results are presented for the DOIG mode of operation, showing larger amount of power captured and better power factor when compared to conventional induction generators.