• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.3
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• pp.409-419
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• 1994

This paper deals with the design criteria and conduction noise reduction of electronic ballast system which is based on half-bridge series inverters. The system is theoretically analyzed in six modes and operating frequency range is selected to obtain the high efficacy and no sound noise. It is proposed the criteria for determining the values of L and C which are the dey points in system design Because of high operating frequency, electromagnetic noise, especially conduction noise, is a serious problem in electronic ballasts. To reduce the conduction noise, the operation and attenuation characteristics of noise filter are analyzed and the method to determine the values of filter elements is proposed. Also, the parasitic components of the inductor and capacitor are taken into consideration in filter analysis. Digital simulations and experiments are carried out to prove the theoretical results. And perfor mances of the system are verified through tests.

• Journal of Electrical Engineering and information Science
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• v.2 no.5
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• pp.129-133
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• 1997

A circuit model for a field emission triode has been proposed. The model parameters have been extracted from he fabricated silicon tip array and verified by comparing with the results simulated by circuit simulator(SPICE). The cut-off frequency can be calculated from the parametric capacitance and the transconductance values extracted from measurements. For the field emission triode, the capacitance of 3.45fF/tip and the transconductance of 0.94nS/tip have been measured under the emission current of 4.1nA/tip. From these values, the cut-off frequency is predicted to be 43 kHz but th measured one came out to be 6 kHz. because o the parasitic capacitance components.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.79-80
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• 2005

In this paper, the circuit models of optical to electrical(O/E) characteristics of waveguide photodiode(WGPD) submodule are examined. Test structures of WGPD and WGPD submodule were fabricated and S21 parameter was measured to characterize the O/E conversion property. Valid circuit models were derived by RF circuit simulation and O/E characteristics were modeled to analyze the effects of model parameters on the WGPD submodule performances. Based on the results, it can be concluded that the suggested WGPD submodule model can explain the characteristics of the O/E conversion of WGPD submodule, where the parasitic components originated from ribbon bonding block crucially influence on the performance of WGPD submodule, are able to show more efficient property by making compact bonding structure. We propose an effective WGPD submodule bonding structure and it can ensure the 40Gbps operation of WGPD.

• Proceedings of the KIEE Conference
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• 1998.11a
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• pp.112-114
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• 1998

The passive system requires RF-DC converter. RF-DC converter, which is used in microwave region, is more affected by parasitic elements than used in low frequency region. So it is difficult to make the converter. RF-DC converter usually consists of resonator, shottky diode, capacitor, voltage regulator. In this study, we used the rechargeable battery instead of capacitor. If any passive transponder requires more power than general transponder, battery tech of this components is important to apply for the passive system. In this paper, passive transponder, which requires more power than general passive transponder, is presented and compared to general passive transponder.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.202.2-202.2
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• 2003

A bioassay-guided fractionation of the whole extract of Viscum album (a parasitic plant : Loranthaceae) led to the isolation of two triterpenoidal components, oleanolic acid (1), ${\beta}$-amyrin acetate (2), homoflavoyadorinin B (3) as well as large quantity of free fatty acid mixtures as active ingredients of the extract responsible for the antitumoral property. The EtOAc soluble part and BuOH soluble part of the extract demonstrated a significant inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system) and HCT-15 (colon) in vitro, whereas the remaining water soluble part exhibited a poor inhibition. (omitted)

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.161.6-161
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• 2001

Confocal scanning microscopy (CSM) has an important role as the three-dimensional profiler. An image distribution can be reconstructed by a correlation analysis of spots with the bandwidth of radio frequency. But it is a serious problem for the high performance to align the optical components. Especially, the parasitic motion of focus on the detector gives rise to the fatal distortion of an image profile named the extinction effect while using acousto-optical(AO) deflector. An image profile can be regenerated in CSM with many advantages of non-contact, high speed and high resolution comparatively. In addition to the axial response of the primary focus, the lateral movement of it gives a necessity of the unitary lens to the scanning system. While using the beam deflector, the pupil of beam may be fixed at the nominal position. Furthermore, the use of a deflector may result in ...

• Journal of Embryo Transfer
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• v.29 no.2
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• pp.171-175
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• 2014

This study was conducted to determine the efficacy of anthelmintics against gastrointestinal parasitic infestation in periparturient dairy cows and its effect on milk yield and quality. Sixty pregnant cows of 1st & 2nd parity were divided into four groups. The efficacy of anthelmintic treatment was evaluated by counting faecal egg per gram (EPG) compared with pre-treatment values. The milk yield of each cow was recorded in pre and post treatment lactations. Cows of group A were treated with Nitroxynil 10 mg/kg body weight subcutaneously 30 days before parturition, group B were treated with combination of triclabendazole and levamisole 19.5 mg/kg body weight orally at calving and group C treated with $Endex^{(R)}$ at calving and 42 days after. The mean change in EPG 14 days after treatment was significantly higher (p<0.05) in treated (79.1%) cows than control. Average milk yield of group C ($2.8{\pm}0.8$) was significantly higher (p<0.01) than group A ($2.6{\pm}0.7$). Similarly, the average milk yield in all the treated cows was significantly (p<0.01) higher in treated lactation ($2.5{\pm}0.7$) than in the previous lactation ($2.2{\pm}0.7$). The average milk yield in all treated cows was significantly (p<0.01) higher than the control cows. Although, milk yields were higher in second parity than the first, there was no significant difference (p>0.05). The milk protein percentage was significantly higher (p<0.05) in treated group than the control group. Therefore, it may be concluded that periparturient anthelmintic treatment effectively reduced the gastrointestinal parasitic load and improved milk yield.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.10 s.352
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• pp.1-9
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• 2006

In this paper, a couple of 10Gb/s transimpedance amplifiers are realized in a 0.18um standard CMOS technology for optical communication applications. First, the voltage-mode inverter TIA(I-TIA) exploits inverter input configuration to achieve larger effective gm, thus reducing the input impedance and increasing the bandwidth. I-TIA demonstrates $56dB{\Omega}$ transimpedance gain, 14GHz bandwidth for 0.25pF photodiode capacitance, and -16.5dBm optical sensitivity for 0.5A/W responsivity, 9dB extinction ration and $10^{-12}$ BER. However, both its inherent parasitic capacitance and the package parasitics deteriorate the bandwidth significantly, thus mandating very judicious circuit design. Meanwhile, the current-mode RGC TIA incorporates the regulated cascade input configuration, and thus isolates the large input parasitic capacitance from the bandwidth determination more effectively than the voltage-mode TIA. Also, the parasitic components give much less impact on its bandwidth. RGC TIA provides $60dB{\Omega}$ transimpedance gain, 10GHz bandwidth for 0.25pF photodiode capacitance, and -15.7dBm optical sensitivity for 0.5A/W responsivity, 9dB extinction ration and $10^{-12}$ BER. Main drawback is the power dissipation which is 4.5 times larger than the I-TIA.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.9
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• pp.940-946
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• 2015

In this paper, we study a method that amplifies the output gain of a high voltage pulse using 300 kHz or higher frequency. We conducted a study on a method for amplifying the output gain using the resonance between the capacitance components of the load and the parasitic components of the circuit, instead of the conservative method for amplifying the pulse-amplitude by raising the voltage of the power stage. In particular, the method simplifies the circuit configuration throughout the appliance of flyback-type topology instead of the bridge-type. There are advantages that prevent damage from overload and the heat in the output circuit through the hard switching by amplifying the gain of the output voltage applying to the load as given by the capacitance component of the output electrode to the output pulse waveform. This study proposed a method to enhance the spatial and electrical efficiency of the contact-type heating device through the dielectric heating method applied to the field of medical and industrial heating.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.5
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• pp.419-426
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• 2002

A new active lossless snubber for half-bridge dual converter(that is called'dual converter') is proposed in this paper It features soft switching(ZVS) as well as turn-off snubbing in both main and auxiliary switches. Therefore, it helps the dual converter to operate at the higher frequency with a higher efficiency and smaller-sized reactive components. Moreover, since it uses parasitic components, such as leakage inductances and switch output capacitances etc, to achieve the ZVS of power switches, it has simpler structure and lower cost of production. The operational principle, theoretical analysis, and design consideration are presented. To confirm the operation, features, and validity of the proposed circuit, experimental results from a 200w, 24V/DC-200V/DC proto-type are presented.