• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.5
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• pp.96-104
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• 2004

This paper proposes a dc power regenerating systems, which can generate the excessive dc power from dc bus line to ac supply in substations for traction system The proposed regeneration inverter system for dc traction can be used as both an inverter and an active power filter(APF). As an regeneration inverter mode, it can recycle regenerative energy caused by decelerating tractions and as an active power filter mode, it can compensate for harmonic distortion produced by the rectifier substation. From the viewpoint of both power capacity and switching losses, the system is designed on the basis of three phase PWM inverters and composed of parallel inverters, output transformers, and an LCL filter.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.9
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• pp.79-84
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• 2010

This paper discusses the control of generator field using dual IGBT PWM regeneration method to target brushless synchronous generator. If one of PWM bridges happens to fault, it transfers automatically and can be in charge of full load. Also it has an advantage of the operation which UPS connected in parallel with PWM bridge can supply power to excitation system in condition of main power loss. This PWM system supplies field current to generator in one quadrature operation, regenerates field coil energy to main power supplier in four quadrature operation. We designed, manufactured and applied the first trial product at J-power plant.

• Proceedings of the KIPE Conference
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• 2005.07a
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• pp.463-465
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• 2005

This paper proposes a regeneration inverter system, which can regenerate the excessive power form the DC bus line to the AC source for traction systems. The proposed regeneration inverter system for DC traction can reduce harmonics which is a characteristic of the AC current source. The simulation was composed as a prototype model[3.7kW]. Finally, it is shown that the inverter can successfully operate in regeneration mode.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.2 s.257
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• pp.188-194
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• 2007

New diesel engines equipped with common-rail injection systems and advanced engine management control allow drastic decreases in the production of particulate matters and nitrogen oxides with a significant advantage in terms of the fuel consumption and $CO_2$ emissions. Nevertheless, the contribution of exhaust gas after treatment in the ultra low emission vehicles conception has become unavoidable today. Recently the passive type DPF(Diesel Particulate Filter Trap) system for diesel passenger vehicle has been manufactured into mass production from a French automotive maker since the year of 2000. This passive DPF system fully relies on the catalytic effects from additives blended into the diesel fuel and additives injected into the DPF system. In this study, the effects of PM regeneration in the commercial diesel passenger vehicle with the passive type DPF system were investigated in chassis dynamometer CVS(constant volume sampler)-75 mode. As shown in this experimental results, the DPF regeneration was observed at temperature as low as $350^{\circ}C$. And the engine-controlled the DPF regeneration founded to be one of the most promising regeneration technologies. Moreover, the durability of this DPF system was evaluated with a season weather in terms of the differential pressure and exhaust gas temperature traces from a road test during the total mileage of 80,000km.

• Journal of Plant Biotechnology
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• v.7 no.4
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• pp.267-272
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• 2005

Common bean (Phaseolus vulgaris L.) plants were regenerated via organogenesis from mature embryonic axes, cultured on MS medium supplemented with ildole-3-ecetic acid (IAA) and thidiazuron (TDZ) for one week in the dark. Embryonic axillary regions were excised, longitudinally cut to split the both sides, and cultured for two weeks on MS medium supplemented with IAA and TDZ. The combination 0.5 mg $l^{-1}$ TDZ/0.5 mg $l^{-1}$ IAA presented the higher efficiency in shoot regeneration and the combination 0.5 mg $l^{-1}$ TDZ/0.25 mg $l^{-1}$ IAA presented the higher efficiency in conversion of shoots to plants. Regenerating explants were transferred to MS medium containing 1 mg $l^{-1}$ BAP for shoot development. All elongated shoots were rooted in vitro, presented normal phenotype and produced viable seeds. Histological analysis confirmed the mode of regeneration as de novo shoot organogenesis.

• Applied Microscopy
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• v.13 no.1
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• pp.49-61
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• 1983

Protoplast releasing mechanisms from Trichoderma koningii, fine structures of the released protoplsts, and their regeneration mode were studied by scanning and transmission electron microscopy. Two types of protoplast releasing mechanisms were observed. In one mechanism, cytoplasm emerged through a cell wall pore developed by cell lytic enzymes and formed a spherical protoplast. In the other mechanism, as the cell wall became progressively thinner, the inner cytoplasm partially rounded to form nonspherical bodies which became spherical protoplasts after being released into the enzyme solution. But, these two types of protoplast releasing mechanisms did not seem to be. mutually exclusive but could occur on the same mycelium simultaneously. And it appeared that cytoplasm which did not become a protoplast by the first mechanism could from a protoplast by the second mechanism. The preparations contained two types of protoplasts, released from different sites of the mycelia. Those released from younger mycelia had dense cytoplasm and small vesicles. Those released from the older mycelia had less dense cytoplasm and larger vacuoles. In the case of regeneration, before producing normal mycelia, most of the protoplasts assumed aberrant tube and yeast-like-forms. Normal mycelia were produced at the end of the yeastlike-forms and sometimes in the middle of the aberrant tube.

• Applied Biological Chemistry
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• v.35 no.6
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• pp.507-512
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• 1992

A ${\beta}-1,3-glucanase$ of soybean (Glycine max) was isolated, and the effects of benzyladenine(BA) on celluar levels of the enzyme content and activity were studied. The effects of BA on callose content in cell wall and wall regeneration of protoplasts were also studied to show promoting effect of cytokinin in cell wall regeneration and to elucidate action mode of cytokinin. The polypeptide of 21 kD was identified as ${\beta}-1,3-glucanase$, and the cellular content and activity of this polypeptide were decreased by BA treatment. The callose content in cell wall of callus and the wall regeneration of protoplasts were increased by BA treatment. These results indicate that cytokinin promotes cell wall regeneration by inhibition of callose degradation via decreasing ${\beta}-1,3-glucanase$ level in cell.

• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.4
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• pp.359-367
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• 2012

In this paper, the input split type series-parallel hybrid electric vehicle (SPHEV) is established and the interpretation of the dynamic characteristics in four kinds of HEV modes, such as electric vehicle mode, engine mode, hybrid mode, and regeneration mode, is described. For this research, the forward-facing approach simulation method is chosen, which is useful for vehicle dynamic analysis. The rating of each powertrain component is designed based on energy-based concept and electrical peaking hybrid (ELPH) method. Finally, the designed powertrain is evaluated with the developed PSiM simulator and simulation results are shown.

• Journal of Power Electronics
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• v.4 no.4
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• pp.237-245
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• 2004

In this paper, a two-switch high frequency flyback transformer linked zero voltage soft switching PWM DC-DC power converter implemented for distributed DC- feeding power conditioning supplies is proposed and discussed. This switch mode power converter circuit is mainly based on two main active power semiconductor switches and a main flyback high frequency transformer linked DC-DC converter in which, two passive lossless quasi-resonant snubbers with pulse current regeneration loops for energy recovery to the DC supply voltages composed of a three winding auxiliary high frequency pulse transformer, auxiliary capacitors and auxiliary diodes for inductive energy recovery discharge blocking due to snubber capacitors are introduced to achieve zero voltage soft switching from light to full load conditions. It is clarified that the passive resonant snubber-assisted soft switching PWM DC-DC power converter has some advantages such as simple circuit configuration, low cost, simple control scheme, high efficiency and lowered noises due to the soft switching commutation. Its operating principle is also described using each mode equivalent circuit. To determine the optimum resonant snubber circuit parameters, some practical design considerations are discussed and evaluated in this paper. Moreover, through experimentation the practical effectiveness of the proposed soft switching PWM DC-DC power converter using IGBTs is evaluated and compared with a hard switching PWM DC-DC power converter.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.163-167
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• 2000

This study was carried out to identify varietal difference and the inheritance of the ability of plant regeneration in anther culture of rice. The anthers of 33 Japonica, 11 Indica/Japonica, and 3 Indica rice cultivars were culture on $N_6-Y$_1$$ medium with 1 mg/L NAA and 2 mg/L kinetin. The remarkable variability in plant regeneration were observed among the genotypes, ranging from 0.0% to 19.4% Most of Japonica rices were resulted to have better culturability than that of Indica/Japonica and Indica type cultivars. Newly developed Japonica rices, 'Ilmibyeo' and 'Hangnambyeo' showed to have regenerability with the frequency of 19.4% and 18.1% respectively. The segregation mode for callus formation and plant regenerationin anther culture of F$_2$ population of 'Milyang 23/Chucheongbyeo' showed a continuous variation. The variation of plant regeneration frequency in anther culture of F$_2$ plants ranged from 0% to 33.3% with a mean of 6.3% The broad-sense heritability estimated from the ability of plant regeneration was considerably high (82.7%).