• Journal of IKEEE
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• v.21 no.2
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• pp.146-149
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• 2017

In this paper, we propose a wide-range radiation measurement system using GM Tube and NaI(TI) detector. The proposed system is designed as a small module optimized to control and count the detector signal of NaI(Tl) Detector and GM Tube. The radiation dose is measured in a wide-range 0.1uSv/h to 10mSv/h in conjunction with two detectors, and two detectors operate simultaneously at 10uSv/h to 100uSv/h, where the measurement interval overlaps. The radiation dose was selected using a wide-range radiation measurement algorithm that controls the on/off function of the detector in the appropriate interval for the overlapped radiation measurable interval. In order to evaluate the performance of the proposed system, it has been confirmed that the measurement uncertainty of each section is measured as ${\pm}7.5%$ and it operates normally under ${\pm}15%$ of the international standard.

• Proceedings of the KIPE Conference
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• 2016.07a
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• pp.73-74
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• 2016

This paper proposes a wide output range AC/DC converter for a rechargeable battery of electric vehicle. In the proposed wide output range AC/DC converter for rechargeable battery of electric vehicle, the main transformer in the DC/DC stage is divided by two. Therefore, if the switch is connected to the middle tap, then half of the maximum voltage is applied. Otherwise, it can be applied the full range of the high voltage by connecting the switch to the whole tab. And also, it is designed to have a wide output voltage range by applying Vin/2 made by changing the full-bridge to half-bridge by using the bridge change switch of the input stage. As it can be supplied the wide range output voltage with a single module, it has the advantage of space utilization and cost reduction effect.

• Journal of Power Electronics
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• v.19 no.5
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• pp.1099-1107
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• 2019

A soft switching converter with wide voltage range operation is investigated in this paper. A series resonant converter is implemented to achieve a high circuit efficiency with soft switching characteristics on power switches and rectifier diodes. To improve the weakness of the narrow voltage range in LLC converters, an alternating current (ac) power switch is used on the primary side to select a half-bridge or full-bridge resonant circuit to implement 4:1 voltage range operation. On the secondary-side, another ac power switch is adopted to select a full-wave rectifier or voltage-doubler rectifier to achiever an additional 2:1 output voltage range. Therefore, the proposed resonant converter has the capacity for 8:1 (320V~40V) wide output voltage operation. A single-stage hybrid resonant converter is employed in the study circuit instead of a two-stage dc converter to achiever wide voltage range operation. As a result, the study converter has better converter efficiency. The theoretical analysis and circuit characteristics are verified by experiments with a prototype circuit.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.1
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• pp.85-92
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• 2006

A new silicon micro flow sensor with multiple temperature sensing elements was proposed and fabricated in considering wide range flow velocity measuring device. Thermal mass flow sensor measures the asymmetry of temperature profile around the heater which is modulated by the fluid flow. A micro mass flow sensor was normally composed of a central heater and a pair of temperature sensing elements around it. A new 2-D wide range micro flow sensor structure with three pairs of temperature sensing elements and a central heater was proposed and numerically simulated by Finite Difference Formulation to confirm the feasibility of the wide flow range sensor structure. To confirm the simulation result, the new flow sensor was fabricated on silicon substrate and the basic flow sensing properties of the sensor were measured.

• JSTS:Journal of Semiconductor Technology and Science
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• v.1 no.3
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• pp.193-196
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• 2001

For wide locking range, an analog delay locked loop (DLL) was designed with the selective phase inversion scheme and the variable number of delay elements. The number of delay elements was determined adaptively depending on the clock cycle time. During the analog fine locking stage, a self-initializing 3-state phase detector was used to avoid the initial state problem associated with the conventional 3-state phase detector. With these schemes, the locking range of analog DLL was increased by four times compared to the conventional scheme according to the simulation results.

• Journal of Power Electronics
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• v.18 no.4
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• pp.975-984
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• 2018

This work presents a high efficiency phase shifted full bridge (PSFB) DC-DC converter for use in the second stage of a battery charger for neighborhood electrical vehicle (EV) applications. In the design of the converter, Lithium-ion battery cells are preferred due to their high voltage and current rates, which provide a high power density. This requires wide range output voltage regulation for PSFB converter operation. In addition, the battery charger works with a light load when the battery charge voltage reaches its maximum value. The soft switching of the PSFB converter depends on the dead time optimization and load condition. As a result, the converter has to work with soft switching at a wide range output voltage and under light conditions to reach high efficiency. The operation principles of the PSFB converter for the continuous current mode (CCM) and the discontinuous current mode (DCM) are defined. The performance of the PSFB converter is analyzed in detail based on wide range output voltage and load conditions in terms of high efficiency. In order to validate performance analysis, a prototype is built with 42-54 V / 15 A output values at a 200 kHz switching frequency. The measured maximum efficiency values are obtained as 94.4% and 76.6% at full and at 2% load conditions, respectively.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.11
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• pp.1695-1699
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• 2012

This paper is proposed all digital wide-range clock and data recovery circuit. The Proposed clock data recovery circuit is possible input data rate which is suggested is wide-range that extends from 100Mb/s to 3Gb/s and used an phase error detector which can use a way of over-sampling a data by using a 1/2-rate multi-phase clock and phase rotator which is regular size per $2{\pi}$/16 and can make a phase rotation. So it could make the phase rotating in range of input data rate. Also all circuit is designed as a digital which has a specificity against a noise. This circuit is designed to 0.13um CMOS process and verified simulation to spectre tool.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.5
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• pp.808-811
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• 2022

In this paper, a wide-range microphone system for lectures using dual 3D sensors is proposed. A previous work using a single sensor had lowering the detecting threshold to support wide-area. However it was found that an error occurred when lecturer wears clothes with low reflectivity or has small body size. When multiple sensors are used to expand the coverage it could be cause various problems. Each sensor could show different distance to the same target. We derive the rotation angle and and compensate for lecturing microphone system using sensors on the line. The proposed method shows a little improvement in performance by about 1dB compared to the previous works but the performance is uniform in all areas regardless of reflectivity.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.64 no.3
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• pp.143-145
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• 2015

One of the many problems besetting the converter designer is being able to design a switching power supply that can operate in the range of very wide input voltage. Specially, in an emergency diesel generator system, the AVR(Automatic Voltage Regulator) is a regulator which regulates the output voltage of the generator at a nominal constant voltage level. In addition, the AVR must be operated in very wide input voltage. Therefore, a power supply for the AVR must be operated at the very wide input voltage range. In this paper, a quasi-resonant flyback power supply with very wide input voltage range is proposed. Also, the performance of the proposed power supply is demonstrated through experiments.

• Journal of Sensor Science and Technology
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• v.27 no.3
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• pp.160-164
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• 2018

In this paper, a wide dynamic range complementary metal-oxide-semiconductor (CMOS) image sensor with the adjustable sensitivity by using cascode metal-oxide-semiconductor field-effect transistor (MOSFET) and inverter is proposed. The characteristics of the CMOS image sensor were analyzed through experimental results. The proposed active pixel sensor consists of eight transistors operated under various light intensity conditions. The cascode MOSFET is operated as the constant current source. The current generated from the cascode MOSFET varies with the light intensity. The proposed CMOS image sensor has wide dynamic range under the high illumination owing to logarithmic response to the light intensity. In the proposed active pixel sensor, a CMOS inverter is added. The role of the CMOS inverter is to determine either the conventional mode or the wide dynamic range mode. The cascode MOSFET let the current flow the current if the CMOS inverter is turned on. The number of pixels is $140(H){\times}180(V)$ and the CMOS image sensor architecture is composed of a pixel array, multiplexer (MUX), shift registers, and biasing circuits. The sensor was fabricated using $0.35{\mu}m$ 2-poly 4-metal CMOS standard process.