• The Transactions of the Korean Institute of Power Electronics
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• v.17 no.2
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• pp.182-189
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• 2012

In this paper, the input current and output voltage ripple of the soft switching interleaved boost converter was analyzed. Ripples of input current and output voltage with an interleaved method is analysed and as a result, the facts that it has lower ripple current than conventional interleaved method is verified. it means that a capacity of a main inductor can be reduced. Besides, a low capacitance of capacitor which means high lifetime and confidence can be used because of reducing ripples of output voltage. In order to verify the validity of the proposed converter used 10uF film capacitor, experiment was performed, and the efficiency of the proposed converter was measured with variable load and duty conditions.

• ETRI Journal
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• v.38 no.5
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• pp.972-980
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• 2016

An ultra-wideband microwave monolithic integrated circuit high-power amplifier with excellent input and output return losses for phased array jammer applications was designed and fabricated using commercial $0.25-{\mu}m$ AlGaN/GaN technology. To improve the wideband performance, resistive matching and a shunt feedback circuit are employed. The input and output return losses were improved through a balanced design using Lange-couplers. This three-stage amplifier can achieve an average saturated output power of 15 W, and power added efficiency of 10% to 28%, in a continuous wave operation over a frequency range of 6 GHz to 18 GHz. The input and output return losses were demonstrated to be lower than -15 dB over a wide frequency range.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.702-704
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• 2001

This paper investigates efficiency and power factor of Switched Reluctance Motor (SRM) using Finite Element Method considered driving circuit. The efficiency and power factor are calculated in Input terminal and Output terminal respectively. When calculating power factor, apparent power is obtained by effective voltage and current because SRM is operated by switching of driving circuit. Efficiency is calculated by mechanical output and active power. Finally, the characteristics of efficiency and power factor in three proposed models are compared due to the switching pattern.

• International journal of advanced smart convergence
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• v.9 no.3
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• pp.127-136
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• 2020

The purpose of this study is to measure the productivity of fisheries in China's coastal areas (including inland and marine fisheries) and to analyze the factors influencing the development of fishery economy in each province by comparing regional differences. The input indicators used for efficiency analysis are fish farms, ships and staff numbers, and the output indicators are fish catch and net income. In this paper, we used six years of data from 2013-2018 and DEA-Malmquist index was used to analyze the efficiency of coastal fisheries production in 11 areas of China's coast. According to the analysis from 2013 to 2018, the fishery output efficiency in China's coastal areas has improved to some extent, but most provinces and regions are characterized by technological progress, and the technological efficiency still needs to be further improved. The conclusion can provide reference for the development planning and policy measures of regional fishery industry in China's coastal areas.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.1-4
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• 1998

In this paper, we proposed the alternated forward zero voltage switching multi-resonant Converter (AT Forward ZVS MRC). The AT forward ZVS MRC has similar characteristics with clamp mode forward ZVS MRC. So it can reduce the voltage stress to tow or three times a input density [W/inch2]. The proposed converter type is verified through the experimental converter with 48V input voltage, 5V/50W output voltage/power. The measured maximum voltage stress is 170V of 2.9 times the input voltage and the maximum efficiency of 81.66% is measured.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.301-303
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• 2001

This paper proposes the boost input type active clamp DC-DC converter featuring the high efficiency and improved EMI characteristics. The main characteristic of the converter is to operate with the non-pulsating input and output currents. Besides, it has the zero-voltage switching (ZVS) and low voltage stress characteristics. For the proposed converter, the detailed operation principles and the simulation results are presented.

• Proceedings of the Safety Management and Science Conference
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• 2008.11a
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• pp.189-199
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• 2008

It is good to use DEA method as it can measure the efficiency without depending on a specific function like cost function. The method also finds out the most efficient group among the sample groups and gives us a specific number. For example, it shows what kind of factor of inefficient group gives how much input and produces how much output. Originally DEA, which was developed by Charnes, Cooper and Rhodes, allows us not only to measure the relative efficiency of Decision Making Units(DMUs) of non-profit organizations whose success cannot be measured by a single bottom-line figure such as profit but also to integrate several variables, which have different measuring scale, into a single model. Therefore we can use physical scales and financial scales simultaneously in the same model without any transformation process. In this study, price and measurable performance indexes of vehicles are used as input and outputs respectively. The purpose of this study is to propose an effective approach for evaluating the relative efficiency of vehicles and to determine the vehicles have high performance efficiency compared to product cost.

• International Journal of Quality Innovation
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• v.2 no.1
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• pp.1-9
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• 2001

As all the other managerial activities, total quality management (TQM) has also inputs into and outputs from the process. Therefore, the principal managerial efficiency criteria of maximum outputs with minimum inputs should be applied to TQM. In this paper, the methodology for the performance evaluation of TQM by Data Envelopment Analysis (DEA) was proposed. DEA is used to measure the efficiency of TQM for each firm with the input and output data obtained by questionnaire. It is found that there are not significant differences between the firms with and without IS09000 certification and between the large and small-sized firms with respect to the TQM efficiency.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.6
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• pp.592-597
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• 2005

The push pull forward converter is suitable in a low output voltage, a high output current applications with wide input voltage ranges. All magnetic components including output inductor, transformer and input filter can be integrated into single EI/EE core. The integrated push pull forward converter is considered through the comparison of efficiency according to the circuit parameters. The Nicera company's 5M FEE18/8/10C and NC-2H FEI32/8/20 cores are used for the transformer. The integrated push pull forward converter ratings are of $36\~72V$ input and 3.3V/30A output. In case that NC-2H FEI32/8/20 core used in the converter, the efficiency is measured up to $83.5\%$ at the switching frequency 200 kHz and the 11A load. The efficiencies of $76.4\%$ at a full load and $82.95\%$ at a half load are measured.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.12
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• pp.1-6
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• 2008

In this paper, bias control circuit structure have been employed to improve the power added efficiency of the CMOS class-E power amplifier on low input power level. The gate and drain bias voltage has been controlled with the envelope of the input RF signal. The proposed CMOS class-E power amplifier using bias controlled circuit has been improved the PAE on low output power level. The operating frequency is 2.14GHz and the output power is 22dBm to 25dBm. In addition to, it has been evident that the designed the structure has showed more than a 80% increase in PAE for flatness over all input power level, respectively.