• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.29 no.2
• /
• pp.51-56
• /
• 2017

In the case of office buildings, domestic and Chinese evacuation laws were compared regarding the evacuation of horizontal and vertical buildings and evacuation to refuge safety areas. A simulation was conducted based on a refuge safety area in China. In the case of evacuating 1 floor, there was no significant difference in the flow of occupants to an ancillary room area in a domestic or Chinese building, but in China, the corridor width was narrower and the occupants have saw a long. In the case of evacuating 15 floors, the flow of occupants to an ancillary room area was different. In the case of China, it was possible for occupants to enter the ancillary room more quickly because the ancillary room area was wider than those found in domestic buildings, allowing quickly passage the ancillary room door. The results of this study found that if corridor width and ancillary room area were wider, evacuation times could be reduced.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2018.05a
• /
• pp.45-46
• /
• 2018

S2 module, which is one of the Korean type e-Navigation services, is a service concept that monitors the situation onboard and provides an emergency level determination and response guidance to the ship when an alarm occurs. S2 module is divided into fire/ seakeeping / navigation safety sub-module. In this paper, the concept of S2 service based on actual ship is explained through the response guidance case study of navigation safety module in case of abnormal condition in the passenger ship H.

• Journal of the Korean Society of Safety
• /
• v.26 no.5
• /
• pp.17-22
• /
• 2011

This study proposes feature extraction method of pattern recognition by evaluation of weld defects in weld zone of titanium. For this purpose, analysis objectives in this study are features of attractor quadrant and fractal dimension. Trajectory changes in the attractor indicated a substantial difference in fractal characteristics resulting from distance shifts such as porosity of weld zone. These differences in characteristics of weld defects enables the evaluation of unique characteristics of defects in the weld zone. In quantitative fractal feature extraction, feature values of 0.87 and 1.00 in the case of part of 0.5 skip distance and 0.72 and 0.93 in the case of part of 1.0 skip distance were proposed on the basis of fractal dimensions. Attractor quadrant point, feature values of 1.322 and 1.172 in the case of ${\phi}1{\times}3mm$ porosity and 2.264 and 307 in the case of ${\phi}3{\times}3mm$ porosity were proposed on the basis of distribution value. The Proposed feature extraction of pattern recognition in this study can be used for safety evaluation of weld zone in titanium.

• Structural Engineering and Mechanics
• /
• v.82 no.5
• /
• pp.557-569
• /
• 2022

The retrofit of existing structures in high seismic zones is a crucial issue in the earthquake engineering field. The interest of the research community is particularly high for the structures that do not respect current seismic codes and present structural deficiencies such as poor detailing and lack of capacity design provisions. A reinforced concrete (RC) school building is used as case study to show the influence of different knowledge levels on the seismic retrofitting cost assessment. The safety assessment of the case study building highlights deficiencies under both vertical and seismic loads. By considering all the possible knowledge levels defined by the Italian such as by the European codes in order to derive the mechanical properties of the school building constitutive materials, the retrofit operations are designed to achieve different seismic safety thresholds. The retrofit structural costs are calculated and summed up to the costs for in-situ in tests. The paper shows how for the case study building the major costs spent for a large number of in-situ tests allows to save a consistent amount of money for retrofit operations. The hypothesis of demolition and reconstruction of the building is also compared in terms of costs with all the analyzed retrofit options.

• Safety and Health at Work
• /
• v.14 no.1
• /
• pp.124-130
• /
• 2023

The increase in the number of fatal electric accidents over the years has escalated the demand for specialized forensic engineers to determine their relevant technical causes. Likewise, the complexities associated with identifying the causes of electrocution accidents have prompted the General Department of Forensic Science and Criminology at Dubai Police to adopt a new methodology to diagnose electrocution accidents, consisting of an approach that involves medico-legal examination, electrical diagnosis of the evidence, and trace evidence analysis. This paper will discuss the application of the adopted method in further detail by unfolding two case reports. The first report outlines a case in which a worker got electrocuted at a construction site while attempting to turn on a lamp. The second case report involves the death of a technician in a workshop after trying to disconnect a washing machine from its plug. The methodology was utilized during the investigation of both cases, which were attended by the appointed forensic engineers and showed promising results.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.10 no.1
• /
• pp.55-69
• /
• 2007

The paper provides the approach to apply formal methods to the development and certification criteria of defense safety/security-critical software. RTCA/DO-178B is recognized as a do facto international standard for airworthiness certification but lack of concrete activities and vagueness of verification/certification criteria have been criticized. In the case of MoD Def Stan 00-55, the guidelines based on formal methods are concrete enough and structured for the defense safety-related software. Also Common Criteria Evaluation Assurance Level includes the strict requirements of formal methods for the certification of high-level security software. By analyzing the problems of DO-178B and comparing it with MoD Def Stan 00-55 and Common Criteria, we identity the important issues In safety and security space. And considering the identified issues, we carry out merging of DO-178B and CC EAL7 on the basis of formal methods. Also the actual case studies for formal methods applications are shown with respect to the verification and reuse of software components.

• Journal of the Korean Society of Safety
• /
• v.32 no.6
• /
• pp.40-45
• /
• 2017

Chemical accidents generated during maintenance, repair, and normal operation, such as dispersion, fire, and explosions, can cause massive losses like a 2012 hydro fluorine leak in Gumi, South Korea. Since this accident, many researches have studied physical mitigation systems. However, due to many difficulties including potential costs and lack time, it is really hard for many companies to install mitigation systems without prior knowledge. Thus, the efficacy of mitigation system should be evaluated. This study assesses a dike design considering the fluid velocity at an open hole when a leakage accident occurs. It is assumed that leakage materials follow a free fall motion. Throughout case studies, a current KOSHA guide for a dike design was evaluated and new guidelines handling various conditions were proposed.

• Journal of the Korean Society of Safety
• /
• v.35 no.2
• /
• pp.34-46
• /
• 2020

Unlike research focused on existing technologies and individual errors to analyze the causes of incidents, this study approached them from an organization and culture. And this study is not a one way study but cyclical study what can track cause down using causal loop diagram methodology. Four diagnostic criteria for the negative state of the safety culture : secretive, blame, failure to learning, and incremental learning, combine literature study and expert opinion to derive 41 variables. Connecting these variable make 4 causal loop diagrams and total causal loop diagram. Case accumulation in secretive, accident report in blame, knowledge accumulation in failure to learning, near miss discovery in incremental learning are the main variables. Safety incident is the objective variable by classifying them into 4 stages in total loop, leading track as the most affect is case accumulation, and Step 4 as you can see accident report and near miss discovery are the result of tracking down the cause. This study can be used as a basis for improving the management priority and the system in incident prevention.

• Journal of Computing Science and Engineering
• /
• v.10 no.3
• /
• pp.75-84
• /
• 2016

Medical cyber-physical systems (MCPS) integrate sensors, actuators, and software to improve patient safety and quality of healthcare. These systems introduce major challenges to safety analysis because the patient's physiology is complex, nonlinear, unobservable, and uncertain. To cope with the challenge that unidentified physiological parameters may exhibit short-term variances in certain clinical scenarios, we propose a novel run-time predictive safety monitoring technique that leverages a maximal model coupled with online training of a computational virtual subject (CVS) set. The proposed monitor predicts safety-critical events at run-time using only clinically available measurements. We apply the technique to a surgical glucose control case study. Evaluation on retrospective real clinical data shows that the algorithm achieves 96% sensitivity with a low average false alarm rate of 0.5 false alarm per surgery.

• Journal of the Korean Society of Safety
• /
• v.33 no.5
• /
• pp.35-41
• /
• 2018

Chemical accidents generated during maintenance, repair, and normal operation, such as dispersion, fire, and explosions, can cause massive losses like a 2012 hydro fluorine leak in Gumi, South Korea. Since this accident, many researches have studied physical mitigation systems. However, due to the lack of potential costs and time, it is really hard for many companies to install mitigation systems without prior knowledge. Thus, the efficacy of mitigation system should be evaluated. This study assesses a dike design considering the fluid velocity at an open hole when a leakage accident occurs. It is assumed that leakage materials follow a free fall motion. Throughout case studies, a current KOSHA guide for a dike design was evaluated and new guidelines handling various conditions were proposed.