• Journal of the Korea Society for Simulation
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• v.18 no.1
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• pp.17-25
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• 2009

This paper suggests fuzzy-based Segment-Boost method and an effective method for face recognition using the fuzzy-based Segment-Boost. Fuzzy-based Segment-Boost eliminates the limitations of Segment-Boost, and it guarantees improved learning performance and the stability of the performance. By using the fuzzy theory, fuzzy-based Segment-Boost optimizes the selection number of sub-vectors, and leads the optimized learning performance. The fuzzy controller designed in this paper measures learning performance of the fuzzy-based Segment-Boost, and it controls the selection number of sub-vectors by inferring the optimized selection number. The simulation results show that the fuzzy controller inferred the selection number which is very approximate to the true optimized value. As a result, fuzzy-based Segment-Boost showed higher face recognition rate than compared boosting methods and it preserves the velocity of feature selection as fast as that of Segment-Boost. From the experimental results, it was proved that fuzzy-based Segment-Boost has improved and stable performances of learning, feature selection and face recognition.

• Journal of Power Electronics
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• v.6 no.4
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• pp.356-365
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• 2006

This paper presents an improved three-phase PFC power rectifier with a three-phase diode rectifier cascaded four-switch boost converter. Its operating principle contains the operating principle of two conventional three-phase PFC power rectifiers: one switch boost converter type and a two switch boost converter type. The operating characteristics of the four switch boost converter type three-phase PFC power rectifier are evaluated from a practical point of view, being compared with one switch boost converter type and two switch boost converter topologies.

• The Transactions of the Korean Institute of Power Electronics
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• v.23 no.1
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• pp.40-46
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• 2018

In this study, the output voltage balancing characteristics of parallel-input series-output (PISO) boost converter is analyzed. The PISO boost converter is derived by combining two basic boost converters. In comparison with the conventional three-level boost converter, the PISO boost converter can balance the output voltages under an unbalanced load condition without requiring additional circuit components and control strategy. A 2 kW prototype converter is built and tested to verify the output voltage balancing characteristics of the PISO boost converter.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.5
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• pp.889-896
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• 2020

In general, there are various types of boost converters such as Boost converters, Buck-Boost converters, Flyback converters, Push-Pull converters, etc. Among them, Boost converters are the most widely used and step up converters in a very simple form. However, Boost converter has DCM mode operation, big ripple problem and RHPZ problem. In order to solve these problems, a converter to which the new topology was applied was presented, but among them, the KY converter improved the Boost converter's DCM mode operation, the big ripple problem and the RHPZ problem. However, the conventional KY converter has a drawback that the voltage gain is relatively lower than that of the Boost converter. Therefore, in this paper, we proposed a new KY converter that solves the problem of low voltage gain while having the advantages of the conventional KY converter.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.404-407
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• 2011

This paper presents a design of current mode PWM/PFM DC-DC Boost converter. This DC-DC Boost Converter operates with PWM mode at the heavy loads and with PFM mode at light loads. The DC-DC boost converter is designed with CMOS 0.35${\mu}m$ technology. It operates at 500KHz and can drive a load current up to 600mA. It has a maximum power efficiency of 92.1%. The total chip area is $1300{\mu}m{\times}1070{\mu}m$ including pads. The DC-DC boost converter operates in a wide range of load currents while occupying a small chip area.

• Proceedings of the KIPE Conference
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• 2020.08a
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• pp.383-384
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• 2020

본 논문에서는 고승압이 가능한 2-Stage Boost 컨버터의 최대효율 운전을 위한 손실 분석을 수행한다. 2-Stage Boost 컨버터의 최대효율 지점 추정을 위해 앞단 Boost 컨버터의 출력 전압인 V_mid의 변동에 따른 2-Stage Boost 컨버터의 상세한 손실을 분석하며, 손실이 가장 적은 V_mid지점을 도출하였으며 실험을 통해 검증한다.

• Journal of Power Electronics
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• v.10 no.4
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• pp.388-395
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• 2010

An active boost converter for a single phase SRM using series-parallel connected capacitors is proposed in this paper. The proposed active boost converter has two diodes and one power switch with an anti-parallel diode and one additional boost capacitor. The additional boost capacitor could be series or parallel connected to the dc-link capacitor to produce proper excitation and demagnetization voltage. The proposed active boost converter can easily achieve a fast excitation and demagnetization from the capacitor connection. In this paper, series and parallel connected converters are reviewed, and the detailed operating modes as well as the voltage characteristics of the proposed converter are analyzed. The simulation and experimental results shows the effectiveness of the proposed active boost converter.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.867-869
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• 1993

In generally Boost Converter is used for Fuel Cell System. Because the output voltage of fuel cell is too small and greatly depends on the load condition, Boost Converter are required to boost and regulate the Fuel Cell voltage for per conversion efficiency. In this Paper, 6-phase Boost Converter is used to boost the Fuel Cell Voltage and regulate the output voltage. Multi phase converter hag some advantages such as low ripple and filter sine. About the Peak Current Control and compare of the Ripple Current of Boost Converter, we have studied.

• Journal of Korea Multimedia Society
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• v.9 no.10
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• pp.1266-1275
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• 2006

In this paper, we propose a real-lime face detection and tracking algorithm using AdaBoost(Adaptive Boosting) algorithm. The proposed algorithm consists of two levels such as the face detection and the face tracking. First, the face detection used the eight-wavelet feature models which ate very simple. Each feature model applied to variable size and position, and then create initial feature set. The intial feature set and the training images which were consisted of face images, non-face images used the AdaBoost algorithm. The basic principal of the AdaBoost algorithm is to create final strong classifier joining linearly weak classifiers. In the training of the AdaBoost algorithm, we propose SAT(Summed-Area Table) method. Face tracking becomes accomplished at real-time using the position information and the size information of detected face, and it is extended view region dynamically using the fan-Tilt camera. We are setting to move center of the detected face to center of the Image. The experiment results were amply satisfied with the computational efficiency and the detection rates. In real-time application using Pan-Tilt camera, the detecter runs at about 12 frames per second.

• Journal of Korea Multimedia Society
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• v.15 no.5
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• pp.606-614
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• 2012

Face detection using AdaBoost algorithm is one of the fastest and the most robust face detection algorithm so many improvements or extensions of this method have been proposed. However, almost all previous approaches deal with only frontal face and suffer from limited discriminant capability for inclined face because these methods apply the same features for both frontal and inclined face. Also conventional approaches for detecting inclined face which apply frontal face detecting method to inclined input image or make different detectors for each angle require heavy computational complexity and show low detection rate. In order to overcome this problem, a method for detecting inclined face using JointBoost is proposed in this paper. The computational and sample complexity is reduced by finding common features that can be shared across the classes. Simulation results show that the detection rate of the proposed method is at least 2% higher than that of the conventional AdaBoost method under the learning condition with the same iteration number. Also the proposed method not only detects the existence of a face but also gives information about the inclined direction of the detected face.