• Journal of Electrical Engineering and Technology
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• 제8권5호
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• pp.1122-1130
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• 2013

This paper proposes a new design for quick battery charger systems for electric vehicles that consists of a three-phase inverter and a full-bridge converter which use the phase-shift method. The 3-phase inverter controls the input and DC-link voltage by use of a current controller and a voltage controller. The full-bridge converter transfers the DC-link voltage to a fixed output voltage. Designs for the output-side converter and controller for improved performance are proposed in this paper. Design schemes for the filter and controller of an input-side inverter are also presented. Furthermore, the paper proposes a compensation method for the offset current that is caused by switch failure and circuit problems. Simulations and experiments have been performed on a 50kW-battery charger system that is suitable for vehicles. The presented results verify the validity of the proposed method and the superiority of the system over conventional methods.

• 전기학회논문지P
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• 제65권4호
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• pp.268-272
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• 2016

A brush-less type synchronous generator is driven by an internal-combustion engine that is used for emergency source. This kind of generator has to maintain output voltage in a range of some degree under the abrupt load irregular conditions such as a full load trip. This paper suggests a suppression method of increasing the output voltage over the rating. Automatic voltage regulator detects excessive rising of output voltage of the generator and supplies the signals to a switch installed in the rotating exciter through the photo-coupler. The current of main field rapidly decreases by additional resistor of the main filed circuit. Therefore, the output voltage of the generator is maintained effectively. The experimental results verified that the excessive value of the output voltage is limited in the range of 7% of the rated voltage.

• Asian Pacific Journal of Cancer Prevention
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• 제15권1호
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• pp.205-213
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• 2014

The outcomes of first-generation EGFR-TKIs (Gefitnib and Erlotinib) have shown great advantages over traditional treatment strategies in patients with non-small cell lung cancer (NSCLC), but unfortunately we have to face the situation that most patients still fail to respond in the long term despite initially good control. Up to now, the mechanism of acquired resistance to EGFR-TKIs has not been fully clarified. Herein, we sought to compile the available clinical reports in the hope to better understanding the subsequent treatment choices, particularly on whether restoring after a drug holiday or switching to another EGFR-TKI is the better option after failure of one kind of EGFR-TKI.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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• pp.894-897
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• 1987

Listener echos, which arise in multiple 4-wire loop connections(MLC) during the evolving switched telephone network, impare voice-band data signal transmission performance. This paper first shows the calculation method of the total number of listener echo loops over N 4-wire physical loops and presents the additative law for listener echos. It next demonstrates that about 4 dB should be ensured to Eke the transmission loss of intraoffice call path be minimum for the voice-band data service in a digital local switch.

• Tuberculosis and Respiratory Diseases
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• 제76권1호
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• pp.1-7
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• 2014

Maintenance therapy has emerged as a novel therapeutic paradigm for advanced non-small-cell lung cancer (NSCLC). Maintenance therapy that aims to sustain a clinically favorable state after first-line chemotherapy has two strategies. Switch maintenance therapy entails switching to a new and non-cross-resistant agent in an alternating or sequential manner, on completion of first-line chemotherapy. Continuous maintenance therapy keeps ongoing administration of a component of the current regimen after four to six cycles of chemotherapy, if there is a stable disease, or better response. Both maintenance therapies can be continued, until disease progression. The potential evidence regarding maintenance therapy includes providing the opportunity to receive additional treatment, through sustaining tumor shrinkage, and delayed emergence of tumor-related symptom. Thus far, debates over the parameters used to predict the effectiveness of maintenance therapy, financial burden, and uncertainty of improving the quality of life exist. Despite many debates, maintenance therapy, which is currently recommended, has been disclosed to be beneficial.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 F
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• pp.2691-2694
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• 1999

The multi-resonant converter(MRC) can reduce the switching losses exiting in a converter, so it is capable of operating at a high frequency. Such a few MHz high frequency application provides a high power density [$W/inch^{3}$]. But the high voltage stress across a switch of the resonant circuit is about 4$\sim$5 times the input voltage, it causes increasing of the conduction loss in MRC. In this paper, the mode analysis for the suggested AT Forward MRC with low voltage stress is discussed. The operational modes of the AT Forward MRC are divided to 8 equivalent modes according to the two switching sequences, Each mode is analyzed over all of the paper.

• ETRI Journal
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• 제34권4호
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• pp.553-563
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• 2012

Serial peripheral interface (SPI) has been identified as a bottleneck in many wireless sensing systems today. SPI is used almost universally as the physical connection between the microcontroller unit (MCU) and radios, storage devices, and many types of sensors. Virtually all wireless sensor nodes today perform up to twice as many bus transactions as necessary to transfer a given piece of data, as an MCU must serve as the bus master in all transactions. To eliminate this bottleneck, we propose the master-handoff protocol. After the MCU initiates reading from the source slave device and writing to the sink slave device, the MCU as a master becomes a slave, and either the source or the sink slave becomes the temporary master. Experiment results show that this master-handoff technique not only cuts the data transfer time in half, but, more importantly, also enables a superlinear energy reduction.

• International Journal of Control, Automation, and Systems
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• 제1권4호
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• pp.412-430
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• 2003

In many practical problems in signal processing and control, the signal values are often restricted to belong to a finite number of levels. These questions are generally referred to as "finite alphabet" problems. There are many applications of this class of problems including: on-off control, optimal audio quantization, design of finite impulse response filters having quantized coefficients, equalization of digital communication channels subject to intersymbol interference, and control over networked communication channels. This paper will explain how this diverse class of problems can be formulated as optimization problems having finite alphabet constraints. Methods for solving these problems will be described and it will be shown that a semi-closed form solution exists. Special cases of the result include well known practical algorithms such as optimal noise shaping quantizers in audio signal processing and decision feedback equalizers in digital communication. Associated stability questions will also be addressed and several real world applications will be presented.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.1095-1098
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• 1999

We have developed a speaker dependent voice command system(VCS) to control the sunroof in the car using RSC-164 VRP(Voice Recognition Processor). VCS consists of control circuits, microphone, speaker and user switch box. The control circuits include RSC-164, input audio preamplifier, memory devices, and relay circuit for sunroof control. It is designed robustly in various car noisy situations like audio volume, air conditioner, and incoming noise when window or sunroof opened. Each two users can control the car sunroof using seven voice commands on the Super TVS model and five voice commands on the Onyx model. It works well when we drive the car at over 100 km/h with the sunroof opened.

• 전자공학회논문지A
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• 제28A권1호
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• pp.52-59
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• 1991

An effective and accurate delay time model is the key problem in the simulation and timing verification of CMOS logic circuits. We propose a semi-analytic CMOW delay time model taking into account the configuration ratio, the input waveform slope and the load capacitance. This model is based on the Schichman Hodges's DC equations and derived on the optimally weighted switching peak current. The parameters necessary for the model calculation are automatically determined from the program. The proposed model is computationally effective and the error is typically within 10% of the SPICEA results. Compared to the table RC model, the accuracy is inproved over two times in average.