• Title/Summary/Keyword: Secondary phase control

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A Dual-Output Integrated LLC Resonant Controller and LED Driver IC with PLL-Based Automatic Duty Control

  • Kim, HongJin;Kim, SoYoung;Lee, Kang-Yoon
    • Journal of Power Electronics
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    • v.12 no.6
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    • pp.886-894
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    • 2012
  • This paper presents a secondary-side, dual-mode feedback LLC resonant controller IC with dynamic PWM dimming for LED backlight units. In order to reduce the cost, master and slave outputs can be generated simultaneously with a single LLC resonant core based on dual-mode feedback topologies. Pulse Frequency Modulation (PFM) and Pulse Width Modulation (PWM) schemes are used for the master stage and slave stage, respectively. In order to guarantee the correct dual feedback operation, Phased-Locked Loop (PLL)-based automatic duty control circuit is proposed in this paper. The chip is fabricated using $0.35{\mu}m$ Bipolar-CMOS-DMOS (BCD) technology, and the die size is $2.5mm{\times}2.5mm$. The frequency of the gate driver (GDA/GDB) in the clock generator ranges from 50 to 425 kHz. The current consumption of the LLC resonant controller IC is 40 mA for a 100 kHz operation frequency using a 15 V supply. The duty ratio of the slave stage can be controlled from 40% to 60% independent of the frequency of the master stage.

Study on High Efficiency Boosting-up Circuit for Renewable Energy Application (신재생에너지용 연계형 인버터의 고효율 승압에 관한 연구)

  • Jung, Tae-Uk;Kim, Ju-Yong;Choi, Se-Kwon;Cho, Jun-Seok;Kho, Hee-Seok
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2009.05a
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    • pp.336-339
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    • 2009
  • In this paper, such as battery power or solar energy and fuel cells generated from Renewable energy sources, high voltage to low voltage DC-DC Converter for converting the design of the study. System consists of low voltage ($24{\sim}28$ [VDC]) and Boosts the voltage (270 [VDC]) for a 3 [kW] DC-DC converter and control circuit is configured as, Power switch the ST Tomson's Automotive low voltage high current MOSFET switches STE250NS10S (temperature 250A) was applied to the two parallel. Also, Controller's processor used ATMEGA128, and Gate Drive applies and composed Photo Coupler TLP250. development. Input voltage (24V) and output voltage (270V) for Conversion in the H-bridge converter topology of the circuit output side power and voltage to control the implementation of the Phase shift angle control applied. And, 3kW of power to pass appropriate specification of the secondary side as interpreted by the high frequency transformer, and the experimental production and analysis of the experiment

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Effect of Rosemary Extract on Lipid Oxidation, Fatty Acid Composition, Antioxidant Capacity, and Volatile Compounds of Salted Duck Eggs

  • Harlina, Putri Widyanti;Ma, Meihu;Shahzad, Raheel;Khalifa, Ibrahim
    • Food Science of Animal Resources
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    • v.42 no.4
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    • pp.689-711
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    • 2022
  • The purpose of our study was to determine the impact of rosemary extract in duck eggs, as determined by in vitro antioxidant capacity, lipid oxidation, fatty acid profiles, and flavor analyses. Three groups of salted duck eggs were compared: A control group and group enriched with 0.1% and 0.5% (w/v) rosemary extracts for 28 days of salting. In a time-dependent manner, the radical scavenging activity and reduction power of eggs with 0.5% (w/v) rosemary extract were significantly higher those of the control at 28 days after salting. The fatty acid profiles of salted egg were significantly affected by rosemary extract and salting time. Palmitic acid was the most abundant fatty acid in salted egg treated with rosemary extract, followed by linoleic acid and arachidonic acid. Furthermore, the treated eggs contained more docosahexaenoic acid than the control ones. And the treated eggs also have a considerable impact on the lipid oxidation process (primary and secondary oxidation). As a result, rosemary extract can be used as a natural antioxidant spice to prevent oxidation and extend the shelf life of eggs during storage. Furthermore, flavor research using solid phase microextraction - gas chromatography - mass spectrometry and an electronic nose demonstrated that adding rosemary extract to salted eggs could give them a distinct flavor.

Effectiveness of anchorage with temporary anchorage devices during anterior maxillary tooth retraction: A randomized clinical trial

  • Barthelemi, Stephane;Desoutter, Alban;Souare, Fatoumata;Cuisinier, Frederic
    • The korean journal of orthodontics
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    • v.49 no.5
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    • pp.279-285
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    • 2019
  • Objective: This study evaluated the efficiency of anchorage provided by temporary anchorage devices (TADs) in maxillary bicuspid extraction cases during retraction of the anterior teeth using a fixed appliance. Methods: Patients aged 12 to 50 years with malocclusion for which bilateral first or second maxillary bicuspid extractions were indicated were included in the study and randomly allocated to the TAD or control groups. Retraction of the anterior teeth was achieved using skeletal anchorage in the TAD group and conventional dental anchorage in the control group. A computed tomography (CT) scan was performed after alignment of teeth, and a second CT scan was performed at the end of extraction space closure in both groups. A three-dimensional superimposition was performed to visualize and quantify the maxillary first molar movement during the retraction phase, which was the primary outcome, and the stability of TAD movement, which served as the secondary outcome. Results: Thirty-four patients (17 in each group) underwent the final analysis. The two groups showed a significant difference in the movement of the first maxillary molars, with less significant anchorage loss in the TAD group than that in the control group. In addition, TAD movement showed only a slight mesial movement on the labial side. On the palatal side, the mesial TAD movement was greater. Conclusions: In comparison with conventional dental anchorage, TADs can be considered an efficient source of anchorage during retraction of maxillary anterior teeth. TADs remain stable when correctly placed in the bone during the anterior tooth retraction phase.

A Study on Power Conversion System for Fuel Cell Controlled by Micro-Processor (마이크로프로세서에 의해 제어되는 연료전지용 전력변환장치에 관한 연구)

  • Kim, Ju-Yong;Jung, Sang-Hwa;Mun, Sang-Pil;Ryu, Jae-Yup;Suh, Ki-Young
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.21 no.5
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    • pp.10-24
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    • 2007
  • In the dissertation, a power conversion system for fuel cell is composed of a PWM inverter with LC filter in order to convert fuel cell voltage to a single phase 220[V]. In addition, new insulated DC-DC converters are proposed in order that fuel cell voltage is boosted to 380[V]. In this paper, it requires smaller components than existing converters, which makes easy control. The proposed DC-DC converter controls output power by the adjustment of phase-shift width using switch $S_5\;and\;S_6$ in the secondary switch which provides 93-97[%] efficiency in the wide range of output voltage. Fuel cell simulator is implemented to show similar output characteristics to actual fuel cell. Appropriate dead time td enables soft switching to the range where the peak value of excitation current in a high frequency transformer is in accordance with current in the primary circuit. Moreover, appropriate setting to serial inductance La reduces communication loss arisen at light-load generator and serge voltage arisen at a secondary switch and serial diode. Finally, TMS320C31 board and EPLD using PWM switching technique to act a single phase full-bridge inverter which is planed to make alternating current suitable for household

Phase II Study of Preoperative Intra-Arterial Epirubicin, Etoposide, and Oxaliplatin Combined with Oral S-1 Chemotherapy for the Treatment of Borrmann Type 4 Gastric Cancer

  • Xiang, Xiao-song;Su, Yu;Li, Guo-li;Ma, Long;Zhou, Chang-sheng;Ma, Ru-feng
    • Journal of Gastric Cancer
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    • v.20 no.4
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    • pp.395-407
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    • 2020
  • Purpose: A phase II study was conducted to evaluate the safety and efficacy of preoperative, intra-arterial perfusion of epirubicin, etoposide, and oxaliplatin combined with oral chemotherapy S-1 (SEEOX) for the treatment of type 4 gastric cancer. Materials and Methods: A single-center, single-arm phase II trial was conducted on 36 patients with histologically proven type 4 gastric cancer without distant peritoneal or organ metastasis. Patients received 3, 21-day courses of SEEOX preoperative chemotherapy. The primary endpoint was overall survival (OS) and the secondary outcomes assessed were chemotherapeutic response, radical resection rate, pathological regression, toxicities, postoperative morbidity, and mortality. Results: All patients were at an advanced stage of cancer (stage III or IV) and completed the entire course of treatment. Based on changes in tumor volume and peritoneal metastasis, the objective response rate was 55.6% (20/36; 95% confidence interval [CI], 38.5%-72.6%) and the disease control rate was 69.4% (25/36; 95% CI, 53.6%-85.3%). The radical resection rate was 75% (27/36; 95% CI, 60.1%-89.9%) and the proportion of R0 resections was 66.7% (21/36; 95% CI, 50.5%-82.8%). The pathological response rate was 33.3%, of which 13.9% showed complete pathological regression. The median survival was 27.1 months (95% CI, 22.24-31.97 months), and the 2-year OS was 48.5% (95% CI, 30.86%-66.1%). Conclusions: Preoperative SEEOX is a safe and effective treatment for type 4 gastric cancer. Based on these preliminary data, a phase III study will be conducted to confirm the superiority of this regimen over standard treatment.

A novel DC-DC Converter for 3[kW] Fuel Cell System Residential Application (3[kW]급 주택용 연료전지시스템에 사용되는 새로운 DC-DC 컨버터)

  • Lee, S.H.;Mun, S.P.;Lee, H.W.;Suh, K.Y.;Kwon, S.K.
    • Proceedings of the KIEE Conference
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    • 2006.04b
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    • pp.362-364
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    • 2006
  • This paper presents a novel DC-DC Converter for 3 [kW] Fuel Cell System Residential Application. Phase shifted control is employed to regulate the output voltage and achieve soft switching. The transformer leakage inductance is utilized effectively to achieve zero voltage turn on for the power semiconductor switches. The current doubler rectifier has only one diode drop. The transformer secondary winding current rating is one half the load current. The overall effciency of the converter is improved.

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Optimal Cooperation and Transmission in Cooperative Spectrum Sensing for Cognitive Radio

  • Zhang, Xian;Wu, Qihui;Li, Xiaoqiang;Yun, Zi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.2
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    • pp.184-201
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    • 2013
  • In this paper, we study the problem of designing the power and number of cooperative node (CN) in the cooperation phase to maximize the average throughput for secondary user (SU), under the constraint of the total cooperation and transmission power. We first investigate the scheme of cooperative spectrum sensing without a separated control channel. Then, we prove that there indeed exist an optimal CN power when the number of CNs is fixed and an optimal CN number when CN power is fixed. The case without the constraints of the power and number of CN is also studied. Finally, numerical results demonstrate the characteristics and existences of optimal CN power and number. Meanwhile, Monte Carlo simulation results match to the theoretical results well.

Study of Karyotype , Meiosis and Isozyme of Hybrid from cross Lilium longiflorum x L. X elegans (Lilium longiflorum $\times$ L. X elegans 의 자방배양에 의해 얻어진 잡종 F$_1$의 핵형 , 감수분열 및 lsozyme에 대한 연구)

  • 윤의수
    • Korean Journal of Plant Resources
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    • v.1 no.1
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    • pp.80-87
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    • 1988
  • Hybries which was made up by chromosome of L. longiflorum and L. x elegans, using root-tip individual which was obtained through ovary slice culture, and root-tip of these parents, with hoirugen staining, gimsa staining and Q-H staining inaccordance with the location and the existence of secondary construction which waslocating near short arm centromere of No, 1,2,6,9. In metaphase of meiosis ofhybrid which was made up by univalent from 2 individuals to 10 individuals wasobserved, and nuclear plate which was having abnormal type's synthesis amounted to91% of all cells whieh were observed. This result showed the fact that someobstacle arose annormal progress of the divission after that time. 63% of the cellshad micronucleus from 1 individlial to 4 individuals in tetrad phase of meiosisdivision. The peroxidase and $\alpha$ -estelase zymogram phenotypes of parents andhybrids were determined using agarlose IEF gel. Crosses were performed betweenparents bearing dissimilar allelomorphs in orther to discern the genetic control ofthe resolved enzymes. Genetic variation of hybrids were detected at all but 2 plant progenies.

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Combined test of Power Supply System for Korean High Speed Train (고속전철용 보조전원장치 시스템 조합시험)

  • Cho, Hyun-Wook;Kim, Yuen-Chung;Kim, Tae-Hwan;Jang, Kyung-Hyun;Kim, Chul-Ho
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.619-625
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    • 2008
  • Electrical Power supply System conditions of korea high speed train consists of main transformer, four AC-DC PWM converter of Auxiliary Block, Battery Charger in Power Car and Trailer Car, Trailer Inverter, Auxiliary inverter. Main transformer, at nominal voltage of 25kv supplied to secondary winding nominal output Voltage 383Vac, The Auxiliary block consists of AC-DC converters for generating 670VDC power, Auxiliary inverters for ventilation and air compressor, Trailer car inverter provide three phase power supplies at 440Vac for air conditioning and heating. The Battery charger Trailer and Power car supplies 72VDC all necessary equipment to energize the trainset equipment and suppy essential control. This Paper introduces the combined test results of the power supply system for korea high speed train. The main purpose of this combined test is to verify the performance of the power supply system that is designed to operate up to full load test.

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