• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.31-36
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• 1997

Strength test using strain rosette gage have been conducted to investigate safety of an auxiliary tank in a high-pressure air compressor. Thickness of auxiliary tanks in 6063-T5 aluminum at toy are 9mm and 17mm. The result of strength test make a comparison the design in strength of materials by nominal stress and the design in fracture mechanics with consideration of crack size. Summarizing the result: Comparing with the safe working pressure of the strength test and that of the design method in strength of materials by nominal stress with the experimental values, it makes difference 11% and 39% for 9mm and 17mm thickness of auxiliary tanks, respectively, and that of the design method by fracture mechanics, it makes difference 4％ and 5% for them, respectively. It is confirmed that the design by fracture mechanics is more economical and safe design than the design in strength of materials by nominal stress.

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.85-92
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• 2015

Universal Design involves designing products and spaces so that they can be used by the widest range of people possible. Universal Design evolved from Accessible Design, a design process that addresses the needs of people with disabilities. This paper introduces the universal design concept through analysis of causes of railway accident within the urban railway station. Railway accident analysis was performed by the internal facilities. We analyzed the standard of accident type, accident cause and accident subject such as elevator, escalator, stairs etc.

• Nuclear Engineering and Technology
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• v.44 no.3
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• pp.225-236
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• 2012

The Fukushima-Daiichi accident shook the world, as a well-known plant design, the General Electric BWR Mark I, was heavily damaged in the tsunami, which followed the Great Japanese Earthquake of 11 March 2011. Plant safety functions were lost and, as both AC and DC failed, manoeuvrability of the plants at the site virtually came to a full stop. The traditional system of Emergency Operating Procedures (EOPs) and Severe Accident Management Guidelines (SAMG) failed to protect core and containment, and severe core damage resulted, followed by devastating hydrogen explosions and, finally, considerable radioactive releases. The root cause may not only have been that the design against tsunamis was incorrect, but that the defence against accidents in most power plants is based on traditional assumptions, such as Large Break LOCA as the limiting event, whereas there is no engineered design against severe accidents in most plants. Accidents beyond the licensed design basis have hardly been considered in the various designs, and if they were included, they often were not classified for their safety role, as most system safety classifications considered only design basis accidents. It is, hence, time to again consider the Design Basis Accident, and ask ourselves whether the time has not come to consider engineered safety functions to mitigate core damage accidents. Associated is a proper classification of those systems that do the job. Also associated are safety criteria, which so far are only related to 'public health and safety'; in reality, nuclear accidents cause few casualties, but create immense economical and societal effects-for which there are no criteria to be met. Severe accidents create an environment far surpassing the imagination of those who developed EOPs and SAMG, most of which was developed after Three Mile Island - an accident where all was still in place, except the insight in the event was lost. It requires fundamental changes in our present safety approach and safety thinking and, hence, also in our EOPs and SAMG, in order to prevent future 'Fukushimas'.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.2_2
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• pp.285-291
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• 2023

In this paper, in order to secure the safety and productivity of pine cone harvest, modeling and structural analysis of the hammering system for pine cone harvest drone that can easily access pine cone of Pinus koraiensis and collide with them to harvest them was performed. It calculate the equivalent stress for the structure of the hammering system and the yield strength of the applied material by applying the shear force of the stalk at which the pine cone is separated from the branch, and it is to verify the safety of the structure and propose an optimal design through appropriate factor of safety and design change. The shear force of the stalk at which the pine cone was separated from the branch was 468 N, and was applied to both ends of the hammering system. The yield strength of SS400 steel used in the hammering system is 245 ㎫, and the design change and structural analysis were performed so that the Von Mises stress could be less than 122.5 ㎫ by applying the factor of safety of 2.0 or more. As a result of the structural analysis of the frist modeling, the Von Mises stress was 220.3 ㎫, the factor of safety was 1.12, and the stress was concentrated in the screw fastening holes. As a result of the design change of the screw fastening holes, the Von Mises stress was 169.4 ㎫, the factor of safety was 1.45, and the stress was concentrated on the side part. As a result of the design change by changing screw fastening holes and adding ribs, the Von Mises stress was 121.6 ㎫, and the factor of safety was 2.02. The safety of the hammering system was secured with an optimal design with little change in mass. There was no deformation or damage as a result of experimenting on pine cone harvest by manufacturing the hammering system with an optimal design.

• Proceedings of the Korea Society of Design Studies Conference
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• 2001.05a
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• pp.16-17
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• 2001

• Journal of The Korea Institute of Healthcare Architecture
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• v.27 no.3
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• pp.27-37
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• 2021

Purpose: The purpose of this study is to compare the changes in hospital accreditation evaluations, the changes in hospital building design guidelines, and the development of design indicators for reducing medical accidents in the state-of-the-art healthcare providers. Methods: The changes and tools were carefully investigated and compared that had been taken place and used in the building certification standards, design guidelines, and patient safety design standards to reduce accidents in the United States and the United Kingdom. Results: First, medical accidents are recognized as multiple defense layers rather than personal ones, and a public reporting and learning system is created, reporting the accidents in question publicly and suggesting ways to improve them based on the data at a time. Second, for the accreditation institute that secures the service quality of medical institutions, detailed standards for patient safety are continuously updated with focus on clinical trials. The United States is in charge of the private sector, but on the other hand the United Kingdom is in charge of the public sector. Third, the design guidelines are provided as web-based tools that complement various guidelines for patient safety, and are improved and developed as well. Fourth, detailed approaches are continuously developed and provided to secure patient safety and reduce medical accidents through appropriate research, evidence-based design and strict evaluations. Implications: When medical institutions make efforts to strength patient safety methods through valid design standards, accidents are expected to decrease, whereby hospital finances are also to be improved. A higher level of medical quality service will sure be secured through comprehensive certification evaluation.

• Journal of the Korea Safety Management & Science
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• v.16 no.3
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• pp.145-154
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• 2014

Performance based design(PBD) is the method to make a fire safety design against them after predicting the factors of fire risk in a building. Therefore, predicting fire risk in a building is very important process in PBD. For predicting fire risk of a building, an engineer of PBD must consider various factors such as ignition location, ignition point, ignition source, first ignited item, second ignited item, flash over, the state of door and fire suppression system. But, it is difficult to trust fire safety capacity of the design because the process in Korea' PBD is unprofessional and unreasonable. This paper had surveyed some cases of PBD that had been made in Korea to find the problems of the process to predict fire risk. And it have proposed the improvements of process to predict fire risk of a building.

• Communications for Statistical Applications and Methods
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• v.26 no.2
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• pp.163-173
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• 2019

Simon's two-stage designs are frequently used in phase II single-arm trials for efficacy studies. A concern of safety studies is too many patients who experience an adverse event. We show that Simon's two-stage designs for efficacy studies can be similarly used to design a two-stage safety study by modifying some of the design parameters. Given the type I and II error rates and the proportion of adverse events experienced in the first stage cohort, we prescribe a procedure whether to terminate the trial or proceed with a stage 2 trial by recruiting additional patients. We study the relationship between a two-stage design with a safety endpoint and an efficacy endpoint as well as use simulation studies to ascertain their properties. We provide a real-life application and a free R package gen2stage to facilitate direct use of two-stage designs in a safety study.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3595-3603
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• 2022

Nuclear safety-class DCS is used for nuclear reactor protection function, which is one of the key facilities to ensure nuclear power plant safety, the maintenance for DCS to keep system in a high reliability is significant. In this paper, Nuclear safety-class DCS system developed by the Nuclear Power Institute of China is investigated, the model of reliability estimation considering nuclear power plant emergency trip control process is carried out using Markov transfer process. According to the System-Subgroup-Module hierarchical iteration calculation, the evolution curve of failure probability is established, and the preventive maintenance optimization strategy is constructed combining reliability numerical calculation and periodic overhaul interval of nuclear power plant, which could provide a quantitative basis for the maintenance decision of DCS system.

• Journal of the Korean Society of Safety
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• v.35 no.3
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• pp.24-31
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• 2020

The duty of construction clients in WSH (Workplace Safety and Health) system was included in the amendment of Occupational Safety and Health Act (enforced on 16 January 2020), which was estimated the shift of paradigm in the prevention of construction accidents. The purpose of this paper is to introduce the analysis results of construction clients' role in the construction project, which were performed by authors over the recent years in order to impose the duty on construction clients, and to suggest their role according the plan, design, and construction stage. Utilizing the systematic literature review process based on Meta analysis, the related papers were selected. For the selected papers, related domestic and foreign regulations, and other prominent report, the construction clients' role was analyzed by reflecting the experts' advice. Results show that the construction clients should control the designer and contractor for implementing the WHS system during the whole process of the construction project. They should supply sufficient source and time to ensure the workers' safety. In the plan stage, the key role of construction clients is to identify intensively controlled hazard and risk reduction plan and to transfer the results. In the design stage, their key role is to select the designer with the capacity in WSH and to assist the designer for the safety design. The main key role of construction clients in the costruction stage is to select the contractor with specialty in WSH including a contract reflecting the WSH requirement and to check implementation of WSH plan, WSH cost, WSH education, and accident report. In addition, it is thought that the construction clients' participations in the site WSH activity and adjustment of safety and health problem among contractors can be effect in the prevention of construction accidents.