• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.185-186
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• 2006

현재 한국전기연구원에는 국내 외 보호계전기의 사용전 검사시험이 년간 약 6,000여대 이상 의뢰되고, 이를 처리하기 위한 특성시험에만 약 3,000 시간 이상이 소요된다. 이와 같은 시험 수요량을 처리하기 위해서는 보호계전기가 가진 각 보호 요소의 특성 시험에 필요한 일련의 과정을 자동으로 수행하고 그 결과를 저장하여 시험을 신속하게 처리하고, 시험자의 시험 설비 조작 또는 결선의 실수로 인한 영향을 최소로 하여 정확한 시험결과를 도출할 수 있는 보호계전기 특성 자동 시험 시스템이 필요하다. 본 논문에서는 보호계전기 보호 요소의 특성 시험시 필요한 시험 장비를 시스템으로 구성하고 이들을 제어하고 결과를 저장, 출력이 가능한 소프트웨어를 개발하고자 한다.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.64-65
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• 2006

This paper presents a user-friendly application for stochastic assessment of voltage sag and effective visualization for analysis data. This developed tool provides basic functions for voltage sag assessment such as load flow analysis, short circuit analysis and vulnerability analysis. Particularly it has the ability to edit one-line diagram of power system and to visualize analysis results effectively using computer graphic and animation. In order to give the real sense, analysis results are displayed with geographical information in an intuitive and rapid manner.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.494-495
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• 2006

개폐기, 차단기와 같은 스위치기어들은 지중케이블이나 가공선로, 콘덴서 뱅크에 흐르는 진상 전류의 개폐를 많이 하게 된다. 이때 진상전류의 크기는 정격 차단전류나 부하전류보다 그 크기가 매우 작다. 그러나 스위치기어 측면에서는 전압을 고려하였을 때 가혹한 시험이며, 이는 차단 후 극간에 걸리는 과도한 회복전압에 기인한다. 본 논문에서는 국제규격에서 요구하는 진상전류 시험의 회로조건들을, 회복전압 측면에 바탕을 두고 고찰해 보았다.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.252-254
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• 2006

분산전원의 계통 연계 증가로 인하여 전력계통의 과도안정도에 미치는 영향 역시 증가하고 있으며, 이로 인하여 재폐로에 미치는 영향 역시 증가하고 있다. 과도 안정도 평가 방법으로는 등면적법, 확장 등면적법, 과도 에너지 함수법 등이 있다. 이 중 과도 에너지 함수법은 포텐셜 에너지와 운동 에너지를 이용하여 과도 안정도를 평가하는 방법으로 분산전원이 연계된 배전계통 같이 복잡한 계통에서 과도 안정도 평가를 용이하게 할 수 있다. 따라서, 본 논문에서는 에너지 함수를 이용한 분산전원 연계 계통의 재폐로 기법을 제시하였다. 에너지 함수를 이용하여 계통의 과도 안정도를 평가하며, 그 여부에 따라 재폐로 방법을 달리한다. 또한, 제시한 기법을 EMTP MODELS로 구현하였으며, 한전 실 계통에 적용하여 그 타당성을 평가하였다.

• Proceedings of the KIEE Conference
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• 2005.11b
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• pp.87-89
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• 2005

If the three phases are not balanced, the current in neutral line is not zero. Then, the induced voltage can be generated In communication line. The KEPCO's rule about unbalanced current in single electric pole is a twenty percent of phase current. But the unbalanced current in double electric pole can't decide the rule because there are many different views. This paper develops the calculation and analysis technique of neutral current in single electric pole and double electric pole using equivalent circuit analysis, vector analysis and EMTP simulation.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.4
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• pp.8-15
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• 1999

The effects of Condebelt press drying on the densification of recycled sheets made from KOCC , AOCC UKP and BKP were examined using CLSM (Confocal Laser Scanning Microscope) and thermal image analysis techniques. It was shown that significant improvement in sheet density, compression strength, tensile strength, surface smoothness was obtained by Condebelt drying. Densification effect by press drying was most prominent for recycled KOCC sheets. And this beneficial effect of Condebelt drying of increasing sheet density and strength was shown to provide opportunities of reducing the utilization ratio of AOCC for cost saving.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.243-249
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• 2011

In the world, burning fossil fuels such as oil, petroleum, gasoline has created the global warming due to especially carbon dioxide gas emission. Therefore, these fossil fuels must be replaced by eco-friendly feadstocks. The wood pellets are one of valuable alternative fuels that can replace oil-based fuels within a short period of time. Unfortunately, there are no enough forest biomass for wood pellets in Korea. Nevertheless, Korea government has been trying to use most of forest biomass generated from the National Forest Management Operation. This does not make sense in an economic point of view.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.131-138
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• 2011

Currently, many forest residues have been generated by the National Forest Management Operation. Unfortunately, most of the forest residues are supposed to be used as raw materials for burning fuels like wood pellets. Even though the forest biomass must be effectively used for making high value-added products, they may be subject to disposable raw materials for wood pellets. Wood pellets are regarded as burning fuels with less contribution to the decrease in carbon gas emission, compared to raw materials for kraft pulps. In this study, we studied whether or not forest biomass mixed with various ages and, species could be used as raw materials for kraft pulps.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.6
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• pp.543-546
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• 2001

Primary intraosseous carcinoma(PIOC) is defined as a squamous cell carcinoma arising within the jaw, having no initial connection with the oral mucosa. The squamous cell carcinoma within the bone can be presumably developed from residues of the odontogenic epithelium, therefore, it is seen in the jaw only. Metastatic carcinoma from another primary site should be excluded in the diagnosis of Primary Intraosseous Carcinoma. This is a case of 62-year-old man, who initially diagnosed as odontogenic cyst on maxilla, but its pathologic examination was diagnosed as squamous cell carcinoma with odontogenic cyst. We treated this patient with partial maxillectomy, modified radical neck dissection(mRND), and postoperative radiation therapy.

• The Journal of Society for e-Business Studies
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• v.4 no.2
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• pp.177-196
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• 1999

The current process of weapon system R&D has lots of problems that the phase is complex, the concept of integration and/or connection of related data is laked and don't be digitalized. To solve these problems we should establish the R&D CALS system and to do this, analysis the R&D process is necessary. In this paper, We suggested weapon system R&D CALS concept and model, and analysed R&D process with ARIS Toolset and proposed the new R＆D process and operation scenarios with CALS concept.