• Journal of the Korean Society of Safety
• /
• v.12 no.4
• /
• pp.169-179
• /
• 1997

The dynamic response of the human brain to direct impact was studied by three-dimensional finite element modeling. The model includes a layered shell closely representing the cranial bones with the interior contents occupied by an incompressible continuum to simulate the brain. Falx and tentorium modeled with 4 node membrane element were also incorporated. The computed pressure-time histories at 4 locations within the brain element compared quite favorably with previously published experimental data from cadaver experiments. Therefore, the purpose of this study was to determine the effects of the impact direction on the dynamic response of the brain in children. A parametric study was subsequently conducted to identify the model response when the age and impact site were varied.

• Journal of the Korean Society of Safety
• /
• v.15 no.1
• /
• pp.1-10
• /
• 2000

This paper deals with rocking response behavior of rigid block structure subjected to horizontal excitation. A strict consideration of impact and sliding between the block and base is essential to investigate the rocking vibration characteristics because the rocking behavior were greatly influenced by the impact and sliding motion. Therefore, not only restitution coefficient between the block and base but also the energy dissipation rate which is associated with sliding motion, and the static and kinetic friction coefficient between those should be included in the modeling of rocking system. The analytic program was developed to be able to simulate the experimental responses of the block subjected to horizontal sinusoidal excitations. By using this program, rocking responses were numerically calculated by the nonlinear equations for rocking system. From the response simulation and rocking vibration experiment, the following results were obtained. The rocking responses are affected by the impact motion due to energy dissipation and friction and provide very complex behavior. The toppling condition of the block is also influenced by the impact motion and sliding motion.

• Journal of the Korea Safety Management & Science
• /
• v.18 no.3
• /
• pp.55-62
• /
• 2016

The purpose of this study is to understand how to affect the safety behavior to the organization's trustees to investigate the level of safety awareness, safety awareness via the distribution center workers prepare the logistics industry disaster prevention measures. The survey was analyzed data to target by the clothing distribution center employees of 182 people. Analysis First, the level of safety awareness showed on a positive effect on organization trust. Second, it was found on the safety level of consciousness a positive effect on the safety behavior. Third, the level of safety awareness affect the safety behavior showed that the mediating role of organization trust. That is a higher level of safety awareness, such as the strict practice of business activities, investments, safety rules on safety education and training emphasis on safety increases confidence in the organization. It was confirmed the higher the confidence in the safety organization appears behavior such as actively participating in the work carried out in a safe manner, safety education and training. In addition, the effect was mediated by the organizational impact on confidence in the safety of personnel safety awareness actions. Based on that research results prepared safety awareness was raised through the industrial accident prevention measures.

• Journal of Korea Ship Safrty Technology Authority
• /
• s.31
• /
• pp.60-70
• /
• 2011

The slamming impact pressures at the bottom area of the Open60' are evaluated by the rules and regulations of various organizations - ISO and classification societies. The enhanced performance of the modern racing yacht in terms of speed which achieves well over 20 knots needs special consideration. The calculated design impact pressures are compared a experimental results. Severe difference can be found in these calculation results but the final conclusion shall be obtained after the scantling calculation under the evaluated design impact pressure so far.

• Journal of the Korean Society of Safety
• /
• v.32 no.3
• /
• pp.83-89
• /
• 2017

A new technology has provided the nation, industry, society, and people with innovative and useful functions. National economy and society has been improved through this technology innovation. Despite the benefit of technology innovation, however, since technology society was sufficiently mature, the unintended side effect and negative impact of new technology on society and human beings has been highlighted. Thus, it is important to investigate a risk of new technology for the future society. Recently, the risks of the new technology are being suggested through a large amount of social data such as news articles and report contents. These data can be used as effective sources for quantitatively and systematically forecasting social risks of new technology. In this respect, this paper aims to propose a data-driven process for forecasting and assessing social risks of future new technology using the text mining, 4M(Man, Machine, Media, and Management) framework, and analytic hierarchy process (AHP). First, social risk factors are forecasted based on social risk keywords extracted by the text mining of documents containing social risk information of new technology. Second, the social risk keywords are classified into the 4M causes to identify the degree of risk causes. Finally, the AHP is applied to assess impact of social risk factors and 4M causes based on social risk keywords. The proposed approach is helpful for technology engineers, safety managers, and policy makers to consider social risks of new technology and their impact.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.15 no.6
• /
• pp.101-108
• /
• 2016

This study was initiated to minimize head injuries, which is the largest cause of increased external activity, traffic accident injuries, and death. We developed a low cost airbag that can be covered by a safety helmet based on consumer needs. The results of the survey showed that safety is the most important aspect of consumers' safety helmets. It also predicted that increasing the weight would present the biggest problem. Curved airbag cushion parts that can be attached to a helmet and the sensor part of a block type were designed. Impact analysis was performed by specifying the pressure inside the airbag and the volume of the airbag as variables.

• Journal of the Korean Society of Safety
• /
• v.31 no.1
• /
• pp.33-40
• /
• 2016

Coupling systems under train's collision should take the impact by absorbing the impact energy caused from the collision, so the systems are very important parts for the safety of the trains. However, it is not easy to evaluate the performance of the system because it requires a huge testing facility, which is able to control the impact and to handle many safety issues. In this paper, test results are provided, which are obtained from collision tests of a single train having a coupling system in the front, and the results are analyzed in order to understand the characteristics and the dynamic behaviors of energy absorbing materials in the coupling system, such as a hydraulic buffer, and two rubber buffers. The results show that the force of each component could be empirically described by the compression displacement and velocity. The analyzed results will be applied to simulation models, and advanced studies wouuld be available if the simulation models are well validated with the test results.

• Journal of the Korea Safety Management & Science
• /
• v.16 no.4
• /
• pp.133-145
• /
• 2014

Aging of the fire organizations, typical disaster response agencies also will be in serious problems with aging society. It is expected that the ratio of more than fifties will reach 31~40% after 10~15 years in Seoul fire organization. This Aging of firefighters can bring about a serious problem in disaster and safety management, since firefighters require robust fitness and healthy bodies in disaster situations. In this study, after the analysis of aging status and trend of firefighters in Seoul, I have an empirical analysis about the impact this aging has on organization effectiveness and QA. As a result, the increase of the elderly reduced organization effectiveness and QA. In addition, in the group consisting of less than 50, it is expected to increase the organization's effectiveness and QA activities through field activity to improve the professional skills with age, but could not be confirmed. In the group consisting of more than fifties, it was found that aging had a significant negative impact on organizational effectiveness and QA activities as factors, including physical deterioration by aging.

• Journal of the Korean Society of Safety
• /
• v.17 no.4
• /
• pp.45-51
• /
• 2002

In this study, the fracture characteristics of carbonized silicon grinding wheels were examined with tensile, compression, impact and bending test. The experiment was performed for the various grinding wheels with grain size #46, #80, and grade H, L, P, and one vitrified bond and one structure No.7. Also the centrifugal fracture rpm of carbonized silicon grinding wheels were measured and compared with the calculated values for the various wheel diameters and thicknesses. The results showed that the fracture tensile strength was $1.5~2.0Kg_f/mm^2$, and it was increased by decreasing grain size and increasing grade. The fracture compression loads were $1,600~3,000Kg_f$, and the inner stress was higher than outer's. And the absorption energy of impact test was 3.3~4.7 J, and it was increased by decreasing grain size but it was not effected by grade. The fracture bending stress was $0.1~0.2Kg_f/mm^2$, and it was increased by decreasing grain size and increasing grade. The centrifugal fracture rpm of carbonized silicon grinding wheel was about 8,500~12,000 and agreed well with the calculated value, and it was increased by decreasing diameter. However, it was almost constant for the reduction of wheel thickness.

• Journal of the Korean Institute of Gas
• /
• v.25 no.6
• /
• pp.74-79
• /
• 2021

This study analyzed the current status of the global hydrogen economy and the safety of energy sources currently in use due to the activation of the hydrogen economy. Understanding the hydrogen economy, identifying government policy trends, comparing and analyzing characteristics with existing energy sources such as gasoline, propane, and methane, and evaluating damage impact for each energy source using PHAST, a quantitative damage impact assessment program. Using the analysis results, this study analyzes the safety of hydrogen energy to revitalize the hydrogen economy and suggests ways to improve safety.