• 수산경영론집
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• 제46권2호
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• pp.43-57
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• 2015

The study aims to identify the current status of aquaculture information in Korea and suggests policy directions for its integrated management. Firstly, the study focuses on the identification of the current status of aquaculture information by reviewing how aquaculture information is managed. Secondly, this study identifies problems such as lacks in necessary aquaculture information, inefficiency caused by dispersion and overlapping of information, absence of integrated management system and insufficient sharing of information. After identifying the current status of aquaculture information and its problems, the study suggests three basic directions to systematically integrate and manage the information such as establishment of infrastructure for promoting the integrated management of aquaculture information, generation and systematic management of useful aquaculture information and enhancement of user convenience. Finally, the study suggests detailed strategies such as establishment of a foundation to facilitate integrated management of aquaculture information, organization of organic network, sharing of more information, creation of necessary information through demand survey, creation of systematic management system, provision of a customized total service, and increase in education and PR activities on information use.

• 대한전자공학회논문지SD
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• 제39권4호
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• pp.93-103
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• 2002

고정도 전류-모드 신호 처리와 집적 회로 설계를 위한 새로운 전류 미러를 제안하였다. 제안한 전류 미러는 입력 임피던스를 줄이기 위해 적응성 귀환 기법을 사용하였고, 출력 임피던스를 높이기 위해 조절된 캐스코드 전류 미러의 출력단을 이용하였다. 시뮬레이션 결과 제안한 전류 미러는 Vcc=5V의 공급기 전압에서 0.9Ω의 입력 임피던스, 415 MΩ의 출력 임피던스, 그리고 0.96의 전류 이득을 가진다. 소비 전력은 1.5㎽이다. 제안한 전류 미러의 응용성을 확인하기 위해 이를 이용한 전압-전류 변환기를 설계하였다. 시뮬레이션 결과, 이 변환기는 이론식과 일치된 결과를 얻었고 월슨 전류 미러를 이용한 전압 전류 변환기보다 3배 이상의 우수한 변환 특성을 가졌다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제15권6호
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• pp.629-633
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• 2015

An active balun using current steering for phase correction is presented. The proposed active balun is constructed with two different unit balun structures based on current steering to reduce phase and amplitude errors. This type of topology can be compared with the conventional phase and amplitude correction techniques which do not incorporate the current steering. Designed and fabricated active balun in $0.18{\mu}m$ CMOS process operates over 0.95 - 1.45 GHz band, showing input reflection coefficient under -15 dB, phase error of $11^{\circ}$ and gain error of 0.5 dB. Gain is measured to be 0.3 dB maximum and power consumption of 7.2 mW is measured.

• 한국초전도ㆍ저온공학회논문지
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• 제21권4호
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• pp.53-58
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• 2019

The critical current is one of the key parameters of high temperature superconducting (HTS) racetrack coils. Therefore, it is significant to calculate critical currents of HTS coils. This paper introduces a fast iterative algorithm for calculating the critical current of second generation (2G) HTS coils. This model does not need to solve long charging transients which greatly reduced the amount of calculation. To validate this model, the V-I curve of four 2G HTS double racetrack coils are measured. The effect of the silicon steel sheet on the critical current of the racetrack coil is also studied based on this algorithm.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 추계종합학술대회
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• pp.884-886
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• 2005

본 논문에서는 main gate와 side gate를 가지는 DGMOSFET의 전류전압특성을 조사하였다. 채널의 길이를 1${\mu}$m에서 5${\mu}$m까지 변화시켜 채널길이에 따른 전류전압특성을 조사하였다. 또한 드레인 전류를 변화시켜 동작온도에 따른 특성변화를 비교${\cdot}$분석하였다. 게이트 전압이 2V 인가되었을 때, 77K에서의 전류전압특성이 300K에서 동작한 소자특성보다 우수하다는 것을 알 수 있었다.

• 전력전자학회논문지
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• 제17권5호
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• pp.401-408
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• 2012

A simple on-line elimination strategy of the dead time and inverter nonlinearity using the current slope information is presented for a PWM inverter-fed IPMSM (Interior Permanent Magnet Synchronous Motor) drive. In a PWM inverter-fed IPMSM drive, a dead time is inserted to prevent a breakdown of switching device. This distorts the inverter output voltage, resulting in a current distortion and torque ripple. In addition to the dead time, inverter nonlinearity exists in switching devices of the PWM inverter, which is generally dependent on operating conditions such as the temperature, DC link voltage, and current. The proposed scheme is based on the fact that the d-axis current ripple is mainly caused by the dead time and inverter nonlinearity. To eliminate such an influence, the current slope information is determined. The obtained current slope information is processed by the PI controller to estimate the disturbance caused by the dead time and inverter nonlinearity. The overall system is implemented using DSP TMS320F28335 and the validity of the proposed algorithm is verified through the simulation and experiments. Without requiring any additional hardware, the proposed scheme can effectively eliminate the dead time and inverter nonlinearity even in the presence of the parameter uncertainty.

• 한국통신학회논문지
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• 제21권6호
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• pp.1596-1603
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• 1996

A single body type of fiber-optic current and voltae sensor using a rare earth doped YIG and a bismuth silicon oxide single crystsl is proposed, which is used for simultaneous measurement of the AC electric current and AC electric voltage over the trasmission lines. Experimental results showed that the fiber-optic current sensor has the maximum 7.5% error within the current range of 0A to 400A, and the fiber-optic voltage sensor has the maximum 0.87% error within the current range of 0V to 400V. The output waveforms of proposed fiber-optic sensor system has a good agreement with output waveforms of conductor current and voltage. Experimental results proved that the output of fiber-optic current sensor is not affected by the electric voltage applied to the fiber-optic voltage sensor, and also, that the output of fiber-optic voltage sensor is not affected by the electric current applied to the fiber-optic current sensor.

• 한국컴퓨터정보학회논문지
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• 제3권2호
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• pp.229-238
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• 1998

현행원가회계시스템의 핵심개념인 경영이익개념은 현행영업이익과 보유이득으로 구성된다. 보유이득의 성격에 대해서는 자본수정설과 이익설의 두가지 견해가 있다. 전자의근거는 조업능력유지개념인 반면, 후자의 근거는 재무자본유지 개념이다. 현행원가회계 주장자들은 그것이 전통회계보다 더욱 유용한 정보를 제공한다고 확신하고 있다. 재무자본지지자들은 현행원가정보가 경영자들의 과거의사결정의 평가에 필요하고, 따라서 그들의 의사결정능력을 개선할 수 있다고 한다. 실물자본지지자들은 기업을 지속적으로 경영하기 위하여 기업의 조업능력이 유지되었는지를 알아야 할 필요성을 강조한다. 역사적원가회계 지지자들은 현행원가회계가 자산을 판매하기 전에 자산가치의 증가를 인식함으로써 전통적인 수익인식원칙을 위반하고, 회계과정에 지나치게 주관성이 개입되어 있다고 믿는다.

• 대한전기학회논문지:전력기술부문A
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• 제52권3호
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• pp.183-192
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• 2003

This paper presents the real-time implemented distance relay algorithm which the fault distance is estimated with only local terminal information. When a single-phase-to-earth fault on a two-parallel transmission line occurs, the reach accuracy of distance relay is considerably affected by the unknown variables which are fault resistance, fault current at the fault point and zero- sequence current of sound line The zero-sequence current of sound line is estimated by using the zero sequence voltage which is measured by relaying location Also. the fault resistance is removed at the Process of numerical formula expansion. Lastly, the fault current through a fault point is expressed as a function of the zero-sequence current of fault line, zero-sequence current of sound line, and line, and fault distance. Therefore, the fault phase voltage can be expressed as the quadratic equation of the fault distance. The solution of this Quadratic equation is obtained by using a coefficient of the modified quadratic equation instead of using the square root solution method. After tile accurate fault distance is estimated. the mote accurate impedance is measured by using such an information.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2004년도 High Temperature Superconductivity Vol.XIV
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• pp.67-67
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• 2004