• Plant Journal
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• v.6 no.2
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• pp.56-61
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• 2010

In this paper, an integrated management software is developed to promote the business competitive power. The interoperability among the software accounts for an ever growing performance of petrochemical plant project. If the interoperability is built up, company has taken advantages of quality, schedule, cost, and safety by active communication. The advantage of an integrated management software is examined in three aspects. In efficiency aspect, It takes advantage of the saving about the various information and the standard of project performance procedure. In quality, the integration gave aid to a quality improvement through team collaboration and data management within project life cycle. In cost, poor communications between systems waste 30% of project costs. If information could be inputted once and used by all, reductions in delivery time up to 40% were possible. Therefore, 10% savings of engineering cost was also possible.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.640-646
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• 2017

A GEN TEST of the auxiliary power unit of a T-50 series aircraft is performed as part of the operational test of its emergency power system on the ground before flight. At this time, the auxiliary power unit should be automatically turned off via the response signal of the ECU when power is not normally supplied to the emergency power system. If the correct operation of the emergency power system cannot be confirmed on the ground, it is not possible to proceed with the flight. This kind of defect is a major factor causing the operation rate of the aircraft to be decreased. The defect code identified by the ECU was confirmed as a defect in the inverter. However, the same defect was found after replacing the inverter. This report presents an improved method of identifying the cause of the defect by analyzing the response characteristics of the ECU and emergency power system and allows the ECU to be recognized as the cause of the defect if the inverter does not generate a voltage within a certain time. Also, the application of the improved method confirmed that it can satisfy the output request time of the emergency power system and effectively prevent the auto-shutdown of the auxiliary power unit.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.131_132
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• 2009

순간전압강하에 대한 다양한 전력품질 보상기기에 대한 투자 여부를 결정하기 위해서는 장비에 대한 기술적이고 경제적인 분석이 필요하다. 전력품질 보상기기에 대한 수명비용을 분석하기 위해 반복 수행에 있어 강력한 모델인 몬테카를로 시뮬레이션을 이용하여 확률론적 위험도 평가를 수행하였으며, 확정모델의 분석 결과와 비교하였다. 확률론적 분석을 통하여 불확실성을 반영한 보다 현실적인 위험도 평가 결과를 얻을 수 있다.

• Journal of Industrial Technology
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• v.12
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• pp.61-67
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• 1992

Two control algorithms of active suspension system for improving ride quality are described and their effectiveness is assessed using a quarter car model. Optimal control approach demonstrates great flexibility to meet various running conditions of a vehicle. However, in order to fully utilize the power of optimal control apporach, accurate estimation of the state variables is essential. Simple, yet effective sky-hook algorithm seems to be well suited for real application because of its much relaxed requirements on sensing the stste variables and relative easiness to implment.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.6
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• pp.1005-1012
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• 1987

An adaptive scalar DCT-Wiener filtering method that can be applied to the problem of restoring an image degraded by white Gaussian noise is presented. In this method, the power spectrum needed to Winer filering is adaptively estimated in block-wise according to the lical properties in transform domain. In addition, overlapping method for reducing the block artifact is considered. Experimental results show that the adaptive Wiener filter by the proposed method yields performance improvement and better image quality over the nonadaptive one and the spatial Lee filter.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2420-2422
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• 1999

To live comportably, proper air and lighting environment are necessary, environment is obtained by excuting. We can get the lighting environment with excuting day-lighting and artificial lighting suittably. The developing trend of fluorescent light lamp call for low power and high lighting efficiency. Nowadays, The 26 mm FL is developed and in wide use in this proper, the character of 26 mm FL is discussed, same improvement are proposed.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1580-1580
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• 2007

광디스크를 재생 및 기록 가능한 기기는 그동안 IT에 용이한 컴퓨터 중심의 ODD(Optical Disc Drive)를 기반으로 급속히 발전해 오고 있었으나, 홈 엔터테인먼트의 발전과 이에 대한 관심의 증폭으로 AV용의 레코더가 2000년대에 등장하게 되었다. AV용 DVD 레코더의 경우 PC용 ODD에 비해 소음 및 세트 내부 온도 등 환경의 영향을 많이 받고, 여러 규격들을 만족해야 하기 때문에 구현에 많은 어려움과 제약이 따른다. 그리고 DVD 레코더는 방송 등을 스트림 기록해야 하므로 기록 신뢰성에 더욱 엄격함을 요구한다. 이에 기록 품질에 관련된 중요 Factor들이 존재하게 된다.

• The Transactions of the Korean Institute of Power Electronics
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• v.19 no.3
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• pp.201-210
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• 2014

In this paper, dc-link voltage control of a grid-connected QZSI is presented. Since the input current of the ZSI is discontinuous, a capacity with relatively large capacitance should be connected to the output of the PV array in order to reduce the current ripple. Due to the presence of the impedance network inductor in series with the PV array, the QZSI can achieve continuous input current flow. Several dc-link voltage control methods are compared and the method for power quality improvement is also presented. The performance of the proposed method is verified through both simulation and experimental results.

• KEPCO Journal on Electric Power and Energy
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• v.8 no.2
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• pp.127-135
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• 2022

With the advent of high technologies such as the 4th Industrial Revolution and artificial intelligence and big data, efforts are being made to solve urban problems and improve the quality of life by applying new technologies in the smart city field. In addition, as carbon neutrality has emerged as an important issue due to global warming, smart city energy platform technologies such as urban energy management, efficiency improvement, and carbon reduction are in the spotlight. In order to effectively manage urban energy, energy resource information such as electricity, water, gas, hot water, heating, etc. must be collected from the management system of various energy utilities and managed on the central platform. The centrally integrated data is delivered to external city management systems that require city energy information through an energy platform. This study developed a CIM profile for smart city energy monitoring required to provide energy data to external systems. Electric data model were designed using the CIM class of IEC 61970, and water, gas, and heat data model were designed in compliance with the UML-based design ideas of IEC 61970.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.11
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• pp.215-222
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• 2018

In this paper, the research on the energy storage system adapting super-capacitor has been performed. The most advanced features compared to the conventional lead-acid battery systems is that it can obtain high power capability due to the super capacitor power characteristics. The suggested system can attain high power in short times and achieve high power quality improvements. The application areas are power quality improvement system, motor start power which requires high power during transient times. The energy conversion system consists of bi-directional converter and inverter and advantages of high speed, high power charging and discharging performances. The design steps for the two loop controller of the bi-directional inverter are suggested and verified by the experiment and manufacturing. The two loop controller design starts from linearized transfer function which is calculated from the state averaging model including state decoupling method. The current controller requirements are 20% overshoot and settling time and voltage controller are no overshoot and settling time which is 10 times longer than current controller. The design is verified from the step input response. The designed controllers have unity power factor characteristics and thus can improve the power quality of the grid. It also has fast response time and zero steady state error.