• Journal of Power Electronics
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• v.19 no.6
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• pp.1486-1495
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• 2019

Dealing with the DC link fault poses a technical problem for an HVDC based on a modular multilevel converter. The fault suppressing mechanisms of several sub-module topologies with DC fault current blocking capacity are examined in this paper. An improved half-bridge sub-module topology with double direction control switch is also designed to address the additional power consumption problem, and a sub-module topology called hybrid double direction blocking sub module (HDDBSM) is proposed. The DC fault suppression characteristics and sub-module capacitor voltage balance problem is also analyzed, and a self-startup method is designed according to the number of capacitors. The simulation model in PSCAD/EMTDC is built to verify the self-startup process and the DC link fault suppression features.

• Steel and Composite Structures
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• v.25 no.2
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• pp.187-196
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• 2017

In this work, transient thermo-piezo-elastic responses of an infinite functionally graded piezoelectric (FGPE) plate whose upper surface suffers time-dependent thermal shock are investigated in the context of different thermo-piezo-elastic theories. The thermal and mechanical properties of functionally graded piezoelectric plate under consideration are expressed as power functions of plate thickness variable. The solution of problem is obtained by solving the corresponding finite element governing equations in time domain directly. Transient thermo-piezo-elastic responses of the FGPE plate, including temperature, stress, displacement, electric intensity and electric potential are presented graphically and analyzed carefully to show multi-field coupling behaviors between them. In addition, the effects of functionally graded parameters on transient thermo-piezo-elastic responses are also investigated to provide a theoretical basis for the application of the FGPE materials.

• Proceedings of the Korea Information Processing Society Conference
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• 2012.04a
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• pp.243-246
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• 2012

클라우드 컴퓨팅 서비스는 눈부신 발전으로 다양한 서비스가 제공되고 있으며 많은 개인 사용자들이 클라우드 서비스에 가입하여 서비스를 제공받고 있다. 하지만 개인 사용자를 대상으로 제공하는 클라우드 서비스는 사용자의 정보를 요구하고 있으며 제공된 사용자 개인정보가 어떻게 보고되는지 개인 사용자는 확인하기 힘들다. 따라서 사용자의 정보 공개를 최소화하는 시스템이 필요하며 사용자의 정보가 없어도 사용자에 맞춤 서비스를 제공할 수 있는 클라우드 컴퓨팅 접근제어 시스템을 제안하고자 한다.

• Journal of Microbiology and Biotechnology
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• v.29 no.6
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• pp.984-988
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• 2019

Blue mold in citrus is caused by Penicillium italicum. In this study, the P. italicum-specific primers were developed for rapid detection based on the conserved genes RPB1 and RPB2 among Penicillium genomes. The two primer pairs RPB1-a and RPB1-b proved to be specific to detect P. italicum. The PCR assay among 39 fungal isolates and the colonial, pathogenic morphologies and molecular methods validated the specificity and reliability of these two primer pairs. This report provided a method and P. italicum-specific primers, which might greatly contribute to citrus postharvest industry.

• ETRI Journal
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• v.41 no.1
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• pp.124-132
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• 2019

The energy balance (EB) model of a primary side regulation (PSR) fly-back converter in the discontinuous conduction mode (DCM) is discussed in this paper. Based on this EB model, the stability of a PSR fly-back converter in the pulse skipping mode (PSM) is analyzed, and a self-adapting modulation factor control strategy is proposed. Theoretical analysis and simulation results show that by saving an optocoupler and correlative circuits, which are necessary in traditional PSM fly-back converters, the modulation factor tolerance controlled by this method is 1.26% on average, corresponding to the ideal value. Compared with traditional fly-back PSM controllers, the power saved in the sampler/comparator modules is 87% on average for a load range of $1{\Omega}$ to $1k{\Omega}$.

• Natural Product Sciences
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• v.25 no.3
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• pp.275-283
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• 2019

In this study, we described the new developed method to simultaneously discriminate two herbal drugs of Artemisiae Argyi Folium and Artemisiae Iwayomogii Herba using eight marker compounds (1 - 8) on an HPLC-PDA system. The developed method was applied to quantify the major components of two herbal drugs. The pattern analysis successfully discriminated and evaluated different components between Artemisiae Argyi Folium and Artemisiae Iwayomogii Herba. Results were used for classification of different species from collected samples.

• Proceedings of the Korea Contents Association Conference
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• 2019.05a
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• pp.317-318
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• 2019

이에 본 논문에서는 중국내 판매되고 있는 재스민 차의 10대 브랜드 "장이위엔(?一元), 우위타이(?裕泰), 이푸탕(?福堂), 수밍룬(蜀茗?), 티엔푸밍 차(天福茗茶), 춘룬(春?), 징화(京?), 비탄피야 오쉐(碧潭?雪), 샤오관차(小罐茶), 중차(中茶)"를 중심으로 패키지 디자인의 4가지 요소(로고, 칼라, 레이아웃, 형태)를 요약하였으며, 이를 바탕으로 소비자 선호도에 대한 설문지를 작성하여 신뢰도와 타당성을 분석하였다. 끝으로 설문조사 결과에 따라 각 요소에 대한 소비자들의 선호도를 분석하고 나아가 재스민 차의 포장 패키지디자인에 대한 제안과 향후 연구계획을 제기하였다.

• Journal of Power Electronics
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• v.19 no.2
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• pp.560-568
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• 2019

This paper studies the inherent relationship between currents and zero-sequence components. Then a precise algorithm is proposed to calculate the injected zero-sequence component to control the DC-Link neutral-point voltage balance, which can result in a more efficient and flexible neutral point voltage balance with a desirable performance. In addition, it is shown that carried-based PWM with the calculated zero-sequence component scheme can be equivalent to space-vector pulse-width modulation (SVPWM). Based on the proposed method, the optimal zero-sequence component of the feasible modulation indices is analyzed. In addition, the unbalanced load limitation of the DC-Link neutral-point voltage balance control is also revealed. Simulation and experimental results are shown to verify the validity and practicality of the proposed algorithm.

• Journal of Power Electronics
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• v.19 no.1
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• pp.1-10
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• 2019

Current imbalance is the main factor affecting the lifespan of light-emitting diode (LED) lighting systems and is generally solved by active or passive approaches. Given many new lighting applications, independent control is particularly important in achieving different levels of luminance. Existing passive and active approaches have their own limitations in current sharing and independent control, which bring new challenges to the design of LED drivers. In this work, a multichannel resonant converter based on switched-capacitor control (SCC) is proposed for solving this challenge. In the resonant network of the upper and lower half-bridges, SCC is used instead of fixed capacitance. Then, the individual current of the LED array is obtained through regulation of the effective capacitance of the SCC under a fixed switching frequency. In this manner, the complexity of the control unit of the circuit and the precision of the multichannel outputs are further improved. Finally, the superior performance of the proposed LED driver is verified by simulations and a 4-channel experimental prototype with a rated output power of 20 W.

• Journal of Information Processing Systems
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• v.15 no.5
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• pp.1243-1257
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• 2019

As current algorithms unable to perform effective fusion processing of unknown complex radar signals lacking database, and the result is unstable, this paper presents a multi-level fusion processing algorithm for complex radar signals based on evidence theory as a solution to this problem. Specifically, the real-time database is initially established, accompanied by similarity model based on parameter type, and then similarity matrix is calculated. D-S evidence theory is subsequently applied to exercise fusion processing on the similarity of parameters concerning each signal and the trust value concerning target framework of each signal in order. The signals are ultimately combined and perfected. The results of simulation experiment reveal that the proposed algorithm can exert favorable effect on the fusion of unknown complex radar signals, with higher efficiency and less time, maintaining stable processing even of considerable samples.