• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.198-200
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• 2001

In this paper, we describe the developed learning tool of expert system for preventive diagnosis of substation power equipments. The expert system was programmed by using the diagnosis methods as like gas analysis in oil and partial discharge, hottest temperature, the current of OLTC driving meter, the current of fan and pump in MTr and driving coil current in GCB and leakage current in LA. The learning tool is composed of the expert system and the explanation of diagnosed examples and the applied rules and it well worked according to the rule.

• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.189-191
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• 2001

This paper described the outputs of acoustic sensors due to the vibration of particles in the mock up GIS. We used the two type of acoustic sensors which had 150kHz resonant frequency and 60kHz resonant frequency respectively. In the experiment of the mock up GIS we paid attention to the relationship between applied voltages and sensor outputs due to particles. In this results fall down voltages depended on the material and length of particles but lift off voltages depended on the materials of particles. And the sensors outputs were increased with applied voltages in the same particle.

• Journal of Yeungnam Medical Science
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• v.26 no.2
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• pp.148-155
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• 2009

Brugada syndrome is characterized by an ECG pattern of right bundle branch block and ST segment elevation in the right precordial leads ($V_1-V_3$) without structural heart disease. It is also characterized by sudden cardiac death that's caused by ventricular fibrillation. This is a familial syndrome with an autosomal dominant inheritance pattern and it may be considerably more common in Southeast Asia. Many factors during anesthesia can precipitate malignant dysrrhythmia in these patients, so careful choice of anesthetics is required. We experienced a case of Brugada syndrome in a 59-year-old male patient who was under general anesthesia for trans-sphenoidal surgery to treat a pituitary adenoma, and the patient was diagnosed as having Brugada syndrome without any untoward cardiovascular events.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.462-469
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• 2011

The design of high-depth and large-section tunnel facilities has been increased lately. The purpose of the design is to avoid inference of existing facilities, enhance public relations and reducing the size of the station, which is advantageous for effective use of underground spaces. Diverse downtown tunnel experience, advanced excavation equipment, reinforcement methods, monitoring technologies and numerical analysis made the design possible. This paper is to introduce the design of high-depth and large-section tunnel facilities via Gimpo airport area of Deagok-Sosa railway BTL project of double-tracking.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1397-1404
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• 2011

Metro serves more than a basic function of transporting passengers between short distances but became a crucial part of civic culture due to the fact that citizens demand various facilities for better life style. Therefore, domestic metro cuts off train noise and air dust, provides pleasant platform surroundings by offering effective HVAC, and establishes PSD (Platform Screen Door) system to prevent falls into train tracks. To control and interlock EMU Door and PSD to avoid passenger complaint and revenue service obstructions, stability and reliability of on-board & wayside equipment are required foremost and each line needs to build optimum interface between on-board & wayside equipment. To control PSD, we would like to introduce examples of Busan Metro(BTC : Busan Transportation Corporation) which already utilizes interface between on-board & wayside equipment in various ways and consider optimum interface between on-board & wayside equipment in future PSD system.

• Korean Management Science Review
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• v.28 no.3
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• pp.95-112
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• 2011

The Internet has generated a number of online review sites where dissatisfied consumers can easily articulate their opinions and comments on products or services. Little attention, however, has been directed to investigating the relationship between negative electronic word-of-mouth (eWOM) and its critical determinants that affect consumers' purchasing behaviors. This study attempts to explore the influence of the key determinants of consumers' negative eWOM behaviors, including their social relationships online. The results show that tie strength is positively associated with the proposed determinants, such as information credibility, external search efforts, and product involvement. Further, we find that perceived risk plays a mediating role in the relationship between consumers' intention to spread eWOM and its key determinants.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.267-274
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• 2004

Since there is a large variation in measurements of the thickness of corroded elements, the thickness of corroded elements are considered as imprecise elements. There is also a considerable degree of uncertainty in a visual assessment of thickness loss. The remaining thickness of a severly corroded element may be represented by an imprecise which expresses the range over which there is uncertainty about the thickness. Therefore, the objective of this paper is to propose a new methodology to safety assessment using imprecise reliability into conventional safety assessment frameworks. For this purpose, this study presents a safety assessment model using Imprecise reliability for large civil structures and demonstrates the applicability of the approach to cable-stayed bridge projects.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.704-711
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• 2005

Recently Life Cycle Cost Analysis for civil infrastructures such as pavements, bridges, and dams has been emphasized However, so far, there are few systems available for life cycle cost analysis of bridges at design stage. Therefore, the objective of this paper is to develop a user-friendly life-cycle cost analysis system for LCC-effective optimal design decision making at design stage. The program is based on the proposed LCC model, formulation, analysis modules and systematic procedure that suit Korean construction conditions. It is expected that the developed system can be effectively utilized for more LCC-effective design of bridges. It is applied to an actual bridge design project in order to demonstrate its effectiveness and applicability.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.30 no.2
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• pp.20-25
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• 2016

This paper describes the effectiveness of continuous water removal in oil immersed transformers. Insulation oil in which insulation papers were immersed were prepared for tests and water concentrations in oil with heating time were measured at five oil temperatures. Also, the tests that water dissolved in $100^{\circ}C$ oil was removed at once and continuously at $50^{\circ}C$ and $100^{\circ}C$ were performed for consideration of effective method for water removal. Test results indicated that the oils for water measurement have to be extracted at similar temperatures and water in oil has to be continuously removed at higher temperatures for more effective water management of transformers.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.119-122
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• 2002

The NiO buffer layers for YBCO coated conductor were prepared on textured Ni substrates by MOCVD method and the degree of texturizing and the surface roughness were analyzed X-ray pole figure and AFM and SEM. Processing variables were oxygen partial pressure and substrate temperature. (200) textured NiO layer was formed at 450~$470^{\circ}C$ and oxygen partial pressure of 1.67 Torr. Out-of-plane($\omega$-scan) and in-plane($\Phi$-scan) texture were $10.34^{\circ}$ and $10.00^{\circ}$ respectively. The surface roughness estimated by atomic force microscopy was in the range of 3.1~4.6 nm.