• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1467-1473
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• 2004

It requires different safety programs from those of the typical train control systems to develop AGT systems applying train control system based on communication technology. Especially Advanced LRT system involves the processes that have the various safety functions being conducted by softwares and also have characteristics that should have special interest in validation of interface specification. The core items for the safety engineering for LRT control systems are hardware & software engineering, safety-critical system safety engineering, application software validation & verification technologies. In this paper the trends of the technologies for the mentioned core-items are described.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.90-95
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• 2008

This article presents practical advice regarding the implementation and management of an impeccable Building Management System. The BMS was introduced to the series of computerized systems including manufacturing, storage, distribution, and quality control. Recently revised GMP regulation is requesting an improvement in drug product quality regulatory system by computer system validation. Quality is critical to guarantee the efficacy and the safety of drugs and is approved in the evaluation process after the audit trail application. HVAC parameter monitoring system will record the identity of operators entering or confirming critical data. Authority to amend entered data should be restricted to nominated persons. Any alteration to an entry of critical data should be authorized in advance and recorded with the reason for the change.

• International Journal of Highway Engineering
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• v.15 no.4
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• pp.127-133
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• 2013

PURPOSES : The impact performance of flexible barrier system such as structural response, vehicular motion and occupant safety vary depending on the impact point. Thus, to properly evaluate the performance of a flexible barrier system, impact should be made to a point which will lead to the worst possible results. This point is called the Critical Impact Point (CIP). This paper presents the way to determine the CIP for a SB2 class flexible barrier system which is consisted of Thrie-Beam rail and circular hollow tube post of 2m span. METHODS: Barrier VII simulations were made for impact points; Case 1 at a post, Case 2 at 1/3 span downstream from a post, Case 3 at middle of the span, Case 4 at 2/3 span downstream from a post. For the structural performance (deflections), impact simulation of 8000kg-65km/h-15degree was used, and for vehicle motion and occupant safety, simulation of 1300kg-80km/h-20degree impact was made and analysed. RESULTS: Case 1 gave the largest dynamic deflection of 75.72cm and also gave the largest snag value of 44.3cm. Occupant safety and exit angle of the vehicle after the impact were not sensitive to the impact point and were all below the allowable limit. CONCLUSIONS : For the SB2 class flexible barrier system's CIP can be regarded as a post which is sufficiently away from the end of Length of Need in order to avoid the end-effect of the barrier system. It can be more economic in the long run because the normal concrete pavement material is likely to cost more due to higher probability of maintenance and repair and higher social cost due to traffic accident, etc.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1915-1920
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• 2015

ISO 26262 is an international standard for the functional safety of electric and electronic systems in vehicles, and this standard has become a major issue in the automotive industry. In this paper, a functional safety compliant electronic control unit (ECU) for an electric power steering (EPS) system and a demonstration purposed EPS system are developed, and a software and hardware structure for a safety critical system is presented. EPS is the most recently introduced power steering technology for vehicles, and it can improve driver’s convenience and fuel efficiency. In conformity with the design process specified in ISO 26262, the Automotive Safety Integrity Level (ASIL) of an EPS system is evaluated, and hardware and software are designed based on an asymmetric dual processing unit architecture and an external watchdog. The developed EPS system effectively demonstrates the fault detection and diagnostic functions of a functional safety compliant ECU as well as the basic EPS functions.

• Journal of Korean Critical Care Nursing
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• v.13 no.2
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• pp.1-11
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• 2020

Purpose : The aim of this study was to compare shift satisfaction, sleep, fatigue, quality of life (QOL), and patient safety incidents between a newly implemented two-shift system and a traditional three-shift system. Methods : A total of 127 intensive care unit nurses (48 two-shift nurses and 79 three-shift nurses) working in a tertiary hospital in Seoul were recruited from January 1, 2017, to March 31, 2017. They completed a self-reported questionnaire about their work hours, shift satisfaction, sleep patterns, sleep quality, fatigue, QOL, and patient safety incidents in the past 2 weeks. Data were analyzed using SPSS version 23.0. Results : The two-shift group showed higher shift satisfaction scores compared with the three-shift group (6.93 vs. 4.37, p<.001). Sleep latency was shorter and sleep quality was better in the two-shift group compared with the three-shift group. There were no significant differences in other sleep parameters, fatigue, QOL, and patient safety incidents between the two groups. Conclusion : Although a two-shift system did not improve nurses' fatigue or QOL in this study, it may effectively serve as an alternative shift-work system that can increase sleep quality and shift satisfaction without increasing patient safety incidents.

• Journal of the Korean Society of Safety
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• v.20 no.3 s.71
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• pp.98-104
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• 2005

This study experimentally and theoretically examines the fire characteristics of 100- by 100- by 50-mm samples of flame retardant treated Douglas fir. Samples were exposed to a range of incident heat fluxes 10 to $50kW/m^2$. The time to ignition measurements obtained from the cone heater were used to derive characteristic properties of the materials. A one-dimensional integral model has been used to predict the, time to ignition, critical heat flux and ignition temperature of samples. Ignition data and best-fit curves confirm ${{\dot{q}}_i}^{'}{\rightarrow}{{\dot{q}}_{cr}^{'}\;then\;t_{ig}{\rightarrow}{\infty}$ and when ${{\dot{q}}_i}^'{\gg}{{\dot{q}}_{cr}^'\;then\;t_{ig}{\rightarrow}0$. And Ignition of flame retardant treated samples occurred not at incident heat flux of bellow $10kW/m^2.$. By a one-dimensional integral model, the critical heat flux of each samples was predicted $10.21kW/m^2,\;11.82kW/m^2,\;and\;14.16kW/m^2$ for the D-N, D-F2, and D-F4, respectively. In ignition temperature of each samples, flame retardant treated samples were measured high about $50^{\circ}C$ than non-treated samples. Water-soluble flame retardant used in this study finds out more effect in delay of time to ignition when incident heat flux is low than high.

• Journal of the Korean Society of Safety
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• v.28 no.1
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• pp.132-136
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• 2013

Even though most of domestic corporations are doing various activities to reduce disasters, it is true that those are actually limited to some parts of business or the formalities in order to obtain specific certificates. For that reason, this writer study a efficient utilization of a guideline about accident provision and business continuity management for less disasters of companies, prevent interruption of critical mission. In short, it is required to operate an effective disaster recovery system and safety management system integrated by a mutual recognition on the relevant parts and different parts. And there is a need to establish a integrated recovery center in order to manage disaster recovery system realistic and effective.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.21 no.2
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• pp.21-25
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• 2013

The system and components for aircraft are required the design data on which the safety requirements are properly reflected for their certification. This paper presents the procedure and results of a safety assessments analysis for the rotorcraft fuel pumps in oder to confirm and verify them. The fuel pumps design assessment must be performed, including a detailed failure analysis to identify all failures that will prevent continued safe flight or safe landing. In order to assess the fuel pumps design safety, not only system safety hazard analysis and but FTA(Fault Tree Analysis) for proofing the safety objective of the fuel pumps are performed. The results of the safety assessment for fuel pumps validate that no single failure or malfunction could result in catastrophic failure or critical accidents of the rotorcraft.

• Nuclear Engineering and Technology
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• v.55 no.1
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• pp.37-44
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• 2023

Using the Kalman filtering technique, we propose a novel method for estimating the missing video frames to monitor the activities inside the control room of a nuclear power plant (NPP). The purpose of this study is to reinforce the existing security and safety procedures in the control room of an NPP. The NPP control room serves as the nervous system of the plant, with instrumentation and control systems used to monitor and control critical plant parameters. Because the safety and security of the NPP control room are critical, it must be monitored closely by security cameras in order to assess and reduce the onset of any incidents and accidents that could adversely impact the safety of the NPP. However, for a variety of technical and administrative reasons, continuous monitoring may be interrupted. Because of the interruption, one or more frames of the video may be distorted or missing, making it difficult to identify the activity during this time period. This could endanger overall safety. The demonstrated Kalman filter model estimates the value of the missing frame pixel-by-pixel using information from the frame that occurred in the video sequence before it and the frame that will occur in the video sequence after it. The results of the experiment provide evidence of the effectiveness of the algorithm.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.382-391
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• 2016

For safety-critical systems including railways, there has been a growing need for effective and systematic safety management processes. The outcomes of efforts in this area are international safety standards, such as IEC 61508, 62278, and ISO 26262. One of the principal activities in the safety process is hazard analysis. For this reason, considerable efforts have been directed toward methods of hazard analysis. On the other hand, the hazard analysis methods reported thus far appear to be unclear in terms of their relationship with the system design process. In addition, in some cases, the methods appear to rely heavily on information regarding the hardware and software components, the number of which is increasing. These aspects can become troublesome when design changes are necessary. To improve the situation, in this paper, hazard analysis was carried out using the result of functional analysis early in the concept development stage for a safety-critical system design. Because hazard analysis is carried out at the system level and the result is then used to develop the safety requirements, improvements can be expected in terms of the development time and cost when design changes are required due to changes in the requirements. As a case study, the generation of safety requirements for the development of light rail transit stations is presented.