• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.86-89
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• 1992

One of the most difficult problems in depth control for underwater vehicle is the effect of seaway disturbance. One component of the seaway forces is of large magnitude with a relatively narrow-band, first order component. The other component is generaly of somewhat smaller magnitude, second order component. Since the magnitude of the first order component is generally much greater than the compensating force that can be generating by the planes, it is undesirable for the controller to generate a control command. In this paper, we disigned adaptive notch filtering system using filter bank structure. Energies of each band-passed signal are obtained by MA(Moving Average) method and compared to produce center frequency. By adapting this parameter to notch filter, 1st order seaway disturbance can be removed, which lead to the improvement of automatic depth control system.

• Journal of Electrical Engineering and Technology
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• v.3 no.4
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• pp.593-598
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• 2008

The power distribution is proposed to determine the target operating points of the system components as the basis for maximal the efficiency of the overall system for a power split dual electric machine hybrid electric bus. The coordinated control is constructed on the basis of the power distribution. The basic coordinated control is implemented to satisfy the driver's power demand, in which both the dynamic characteristics of the engine and the dual electric machine are explicitly taken into account. Moreover, the improved coordinated control is suggested to suppress engine dynamic operation and rich fuel injection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.76-79
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• 2000

The effects of packaging conditions on freshness extension of squash (Cucurbita moscata) were investigated during 7-day storage at 2$0^{\circ}C$. Weight loss of squash packed with corrugated paperboard box (control) was 5.5%, and those of LDPE (low density polyethylene, Ф0.02 mm), LDPE (Ф0.04mm) film and EPS (expanded polystyrene) box were 0.9%, 0.8%, and 1.1%, respectively. Firmness of EPS was 11% higher than that of control, chlorophill content of squash packed with EPS box was 18.9% higher, and total ascorbic acid content of squash packed with EPS box was 29.4% higher than that of control. Quality of packed squash was not different between EPS packages and LDPE packages. Decay of control was 1~2 pieces per box, but was not found in the LDPE, EPS box. Preferences in overall appearences of LDPE, EPS box was better than those of control.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.9
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• pp.520-525
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• 2000

This paper deals with the design of H$\infty$ control for uncertain linear systems with the regional eigenvalue assignment constraint. The considered region is a disk in the left half plane and the two types of time-varying uncertainties are considered. We presents a state feedback control that minimize the L2 gain from the disturbance to the measured output as well as it guarantees that all eigenvalues of closed loop are inside a disk. The state feedback control is obtained by checking the feasibility of linear matrix inequalities (LMI's) which are numerically tractable. Finally we give an example to show the applicability and usefulness of our results.

• Journal of Power Electronics
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• v.14 no.3
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• pp.421-431
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• 2014

A DSP-based self-adaptive proportional-integral (PI) controller to control a DC-DC converter is proposed in this paper. The full-bridge topology is adopted here to obtain higher power output capability and higher conversion efficiency. The converter adopts the zero-voltage-switching (ZVS) technique to reduce the conduction losses. A parallel secondary active clamp circuit is added to deal with the voltage overshoot and ringing effect on the transformer's secondary side. A self-adaptive PI controller is proposed to replace the traditional PI controller. Moreover, the designed converter adopts the constant-current and constant-voltage (CC-CV) output control strategy. The secondary active clamp mechanism is discussed in detail. The effectiveness of the proposed converter was experimentally verified by an IGBT-based 10kW prototype.

• Journal of Power Electronics
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• v.17 no.6
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• pp.1611-1624
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• 2017

With the rapid development of microgrid technology, microgrid projects are no longer limited to laboratory demonstrations and pilot platforms. It shows greater value in practical applications. Hence, the smooth interaction between a microgrid and the main grid plays a critical role. In this paper, a control method based on active disturbance rejection control (ADRC) is proposed in order to realize seamless transitions between grid-connected and islanding operation modes and stable operation with variable loads. It is verified by simulations that the proposed ADRC-based method features better performance when compared to conventional proportional-integral-differential (PID) control. Meanwhile, the stability of the third-order extended state observer (ESO) in second-order ADRC is validated by using Lyapunov stability criteria.

• The korean journal of orthodontics
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• v.26 no.4
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• pp.341-348
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• 1996

The efficiency of maxillary canine retraction by means of sliding mechanics along an 0.016 continuous labial arch and an 0.009 inch in diameter with a lumen of 0.030 inch NiTi closed coil spring was compared with that using the same NiTi closed coil spring and Molar Anchoring Spring(MAS) which was designed by author. MAS was made of .017" X .025" TMA wire and was given 60 degree tip-back bend on the wire close to the molar tube. This study was designed to investigate molar and canine root control during retraction into an extraction site with continuous arch wire system. Two techniques were tested with a continuous arch model embedded in a photoelastic resin. A photoelastic model was employed to visualize the effects of forces applied to canine and molar by two retraction mechanics. With the aid of polarized light, stresses were viewed as colored fringes. The photoelastic overview of the upper right quadrant showed that stress concentrations were observed in its photoelastic model. The obtained results were as follows. 1. Higher concentration of compression can be seen clearly at the distal curvature of the canine and mesial curvature of the molar and premolar when NiTi closed coil spring was applied only, which means severe anchorage loss of the molar and uncontrolled tipping of the canine. 2. The least level compression was presented at the mesial root area of the molar and premolar, and mesial root area of the canine when NiTi closed coil spring and MAS were used simultaneously. Especially mesial alveolar crest region of the canine was shown moderate level of compression that means MAS can be used as a appliance for anchorage control and prevention of canine extrusion and uncontrolled tipping during canine retraction.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.10
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• pp.1444-1451
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• 2009

This study was to examine the shelf life and qualities of castellas added with mixture of Morus alba root bark (MA), Ecklonia stolonifera (ES), and Curcuma aromatica (CA) extracts (MECE). The result of total microbial cell count showed that castellas with MECE were increasing storage time, especially at the rate of MA : ES : CA＝0.75:0.75:0.5, and was reduced about 3 log cycle as compared to that of control. Also castellas with MECE were shown to have the highest antioxidant effect by Rancimat method. In the color, redness of castellas diminished with increasing amounts of MECE in castellas while conversely, lightness and yellowness increased. In sensory evaluation, the castella containing MA 0.25%, ES 0.25% and CA 0.125% were preferred than the control. These results suggest that the addition of MA 0.25%, ES 0.25% and CA 0.125% in castella positively improved the preservation and development of quality.

• Food Science and Preservation
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• v.24 no.1
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• pp.52-59
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• 2017

This study was performed in order to examine the effect of a thermoelectric cooling system combined with plasma on beef. Beef was studied in a box with a thermoelectric cooling system and plasma generation apparatus (TCS-1), a box with thermoelectric cooling system (TCS-2) and a polystyrene box (control). A temperature inside the thermoelectric cooling system was kept below $2^{\circ}C$, and volatile basic nitrogen (VBN) values of TCS-1 and TCS-2 were 7.72 mg% and 9.20 mg%, respectively. The thiobarbituric acid (TBA) value (0.52 mgMA/kg) of TCS-1 was significantly lower than that (0.91 mgMA/kg) of TCS-2. For volatile basic nitrogen (VBN) value, TCS-1 maintained freshness compared to TCS-2, since the freshness of TCS-1 value (6.98-9.77 mg%) was less than that of TCS-2 (6.98-11.45 mg%) during storage. The microbial counts of TCS-1 and TCS-2 were 4.62 log CFU/g and 7.09 log CFU/g, respectively, on the $7^{th}$ day, which were lower than that (8.45 log CFU/g) of control on the $3^{rd}$ day. Sensory evaluation of TCS-1 showed the highest scores for appearance, color, juiciness, and overall acceptability than the others. In conclusion, TCS-1 was effective for maintaining freshness of beef during storage.

• Journal of The Korean Dental Society of Anesthesiology
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• v.14 no.2
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• pp.101-106
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• 2014

Background: Remifentanil, an ultra-short-acting mu-opioid receptor agonist, is unique from other opioids because of its esterase-based metabolism, minimal accumulation, and very rapid onset and offset of clinical action. Remifentanil can prevent the inflammatory response and can suppress inducible nitric oxide synthase expression in a septic mouse model. However, the effects of remifentanil on human keratinocyte and autophagy have yet to be fully elucidated during hypoxia-reoxygenation. Here we investigated whether remifentanil confers protective effect against hypoxia-reoxygenation in human keratinocyte and, if so, whether autophagy mediates this effect. Methods: The human keratinocytes were cultured under 1% oxygen tension. The cells were gassed with 94% $N_2$, and 5% $CO_2$ and incubated for 24 h at $37^{\circ}C$. To determine whether the administration of affects human keratinocytes hypoxia-reoxygenation injury, cells were then exposed to various concentrations of remifentanil (0.01, 0.1, 0.5 and 1 ng/ml) for 2 h. After remifentanil treatment, to simulate reoxygenation and recovery, the cells were reoxygenated for 12 h at $37^{\circ}C$. Control group did not receive remifentanil treatment. Normoxia group did not receive hypoxia and remifentanil treatment for 36 h. 3-MA group was treated 3-methyladenine (3-MA) for 1h before remifentanil treatment. Cell viability was measured using a quantitative colorimetric assay with MTT, showing the mitochondrial activity of living cells. Cells were stained with fluorescence and analyzed with Western blot analysis to find out any relations with activation of autophagy. Results: Prominent accumulation of autophagic specific staining MDC was observed around the nuclei in RPT group HaCaT cells. Similarly, AO staining, red fluorescent spots appeared in RPT group HaCaT cells, while the Normoxia, control and 3-MA groups showed mainly green cytoplasmic fluorescence. We here examined activation of autophagy related protein under H/R-induced cells by Western blotting analysis. Atg5, Beclin-1, LC3-II (microtubule-associated protein 1 light chain 3 form II) and p62 was elevated in RPT group cells. But they were decreased when autophagy was suppressed by 3-MA (Fig. 5). Conclusions: Although the findings of this study are limited to an in vitro interpretation, we suggest that remifentanil may have a beneficial effect in the recovery of wound from hypoxia-reoxygenation injury.