• Journal of Advanced Marine Engineering and Technology
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• v.39 no.10
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• pp.1037-1043
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• 2015

In recent years, Floating Liquefied Natural Gas (FLNG) Unit have attracted considerable attention. Generally, liquefied natural gas (LNG) units are produced in onshore liquefaction terminals from gas supplied from onshore gas fields or large-scale offshore gas fields near the coast. However, the development of these gas fields has approached saturation. Large-scale offshore gas fields far from the coast, as well as undeveloped medium- and small-scale offshore gas fields, have recently attracted attention. Among several proposed concepts, the floating LNG plant in the form of the FLNG system was chosen for further evaluation and development, considering worldwide receiving infrastructure. The design of a 2.5 million tonne per annum FLNG unit has been completed with a capacity corresponding to that of modern onshore liquefaction plants. Various simulation tests were performed to evaluate the performance of the electrical power plant, focusing on the efficiency of the electrical system to secure the aspects of plant safety. This design study analyzes the electrical system for the FLNG unit to improve the safety of operation and maintenance in the field.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.438-440
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• 2003

It is very important to ensure system safety during the process of developing a system. Railway system is also devoting a great portion for the safety. Nowadays many countries leading railway industry have their own system assessment process according to the situation of their train control system. In this Paper, several methods to derive Tolerable Hazard Rate are represented in the railway signalling system the characteristics of those methods are also considered respectively.

• Proceedings of the Safety Management and Science Conference
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• 2011.04a
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• pp.719-730
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• 2011

The live-line works are very dangerous works on direct contacts or neighboring contacts with the distribution line. But most of domestic electrical construction companies that have performed live-line works are small-scale companies. Accordingly, safety management system and manuals to insure worker's safety haven't sufficiently had. In this paper, risk and status of accidents for the live-line works were analyzed and the necessity of introducting risk assessment for live-line works was identified by a questionnaire survey of electrical construction companies and education institutions.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.12
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• pp.573-578
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• 2003

In this study, new type of induction charging system for electrostatic spraying was manufactured and proposed to improve the electrical safety and charging efficiency. And parameters of proposed system to generate the maximum deposition current with electrical safety were selected and investigated. The selected parameters were frequency of square pulse and thickness of insulation material, outer diameter of device and thickness and positions of electrode. Charging quantity of water drop was measured by deposition current detected from sensing plate indirectly. The maximum deposition current for each parameter were 3.5[uA] at the frequency of 15[kHz] and thickness of 0.25[mm] insulating layer. And maximum deposition currents were 2.8[uA] and 3.0[uA] at 25[mm] outer diameter of charging device and 0.25[mm] thickness of electrode each. Effects of electrode position from spraying nozzle on deposition current was a little.

• Proceedings of the KIEE Conference
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• 2007.11b
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• pp.66-68
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• 2007

The regulatory guide, RG-1.204 and its underlying or confirmatory research, NUREG/CR-6866 were studied for Korean application to LPGS of NPPs. However they excluded the application to that of NPPs. So US-NRC approved selectively industrial standards to that of NPPs on Nov 2005. It is necessary to understand the basis of regulatory technology related regulatory positions on LPGS and important to implement the guidance on LPGS as a resonable standard. The paper is examined what and how state of the art of relevant technology applied to the LPGS as well as the trip-out events related to electrical system were involved with LPGS. We reviewed the relevant standards applicable to Korean NPPs. Following are concluded to recommend. (1) IEEE 510-1050 is recommended as a guide for I&C grounding against EMI and lighting transients (2) IEEE Std-665, 510-666, Std-C62.23 for electrical grounding against voltage surges and lighting transients (3) Inspection should be thoroughly be implemented a frequency of 3-5 year period according to NFPA780 or KSC-IEC 61024.

• Journal of Biomedical Engineering Research
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• v.44 no.3
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• pp.190-203
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• 2023

The purpose of this study is to provide basic data to ensure the safety and essential performance of a Lower Extremity robotic assisted gait training system and to provide advanced technology and technical basis to the industry handling the system. Based on IEC 60601-1:2012/AMD2:2020 (Medical Electrical Equipment - General requirements for basic safety and essential performance of medical electrical equipment), IEC 62366-1:2015/AMD1:2020 (Medical devices - Part 1: Application of usability engineering to medical devices) and EN ISO 14971:2019 (Medical devices - Application of risk management to medical devices), the requirements for ensuring the safety and essential performance of the Lower Extremity robotic assisted gait training system were derived. Through the Delphi survey method and scenario analysis, which reflects the opinions and knowledge of experts in the fields of development, testing and review of technical documents, and quality assurance of medical devices, validity and reliability were conducted and obtained results with adequate content validity ratio (CVR; 0.7≤) and excellent reliability (Cronbach's α; 0.9≤). As a result, it was confirmed that the reliability and validity of the risk management process to ensure the safety and essential performance of the Lower Extremity robotic assisted gait training system are required a model can be established to provide measures to reduce risks according to the level of risk exposure caused by usage.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.195-197
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• 2007

This paper presents experimental results on the safety of persons due to a ground fault in 22.9 kV-Y distribution system In order to evaluate the touch voltages due to internal ground faults in a step down transformer based on the newly prescribed KS C IEC 60364 standard series, the verification tests in a 22.9 kV multi-grounded neutral system were carried out From the experimental results, it was found that there will be significant potential rise jeopardizing LV equipment insulation in case of separate grounding between HV and LV system and the effective measures against hazardous touch voltages due to a IN side ground fault in the common grounding system between HV and LV system are proposed. As a consequence, it was found that the equipotential bonding is an important prerequisite for the effectiveness of the protective measures for the safety of persons in the common ground system between 22.9 kV-Y and low-voltage grounding system.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.67 no.3
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• pp.160-167
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• 2018

In this paper, a black box, which is provided the reliability and user safety of home battery energy storage system connected with solar energy generation, is developed. In the developed scheme, a status and diagnosis data of battery management system, power conditioning system, solar energy generation and grid is measured. This status and diagnosis data is stored and displayed in the developed black box. In addition, this status and diagnosis data is stored and displayed in a monitoring system and a smart phone of user. A performance evaluation of the developed black box is carried out using emulator of home battery energy storage system connected with solar energy generation. Consequently, the developed black box is proved its superiority of the reliability and user safety.

• Proceedings of the KIEE Conference
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• 2006.10d
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• pp.244-246
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• 2006

Softwares in railway system are being used in the area of railway control system, directly associated to safety. Because the instinct characteristic of Software is uncertainty, Software development without safety insurance is very hazardous situation. In order to derive safety certification process in the railway system, certification and approval processes in the nuclear, aviation, and military area are studied. Software quality should be improved by two aspects : one is product aspect, another is process aspect. GS(Good Software) and ES(Excellent Software) certification can be exemplified in a product aspect approach. In those process certification, CMMI (Capability Maturity Model Integration) or SPICE (Software Process Improvement and Capability dEtermination : ISO/IEC15504) is being used as models for assessing process maturity of organization. Following the studies, safety management procedure in the railway system is suggested.

• Proceedings of the KIEE Conference
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• 2002.04a
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• pp.270-272
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• 2002

The safety of the present railway system has been established through a lot of experience from the railway accident. But nowaday scientific safety assessment methods are exactly required to improve the safety of railway system. In this study, we focused on the methodology of probabilistic risk assessment, which has been developed mainly in the field of nuclear power industry, and considered the process to adopt this method to railway system in order to establish a scientific and comprehensive way of safety assessment.