• Transactions of the Korean Society of Automotive Engineers
• /
• v.16 no.6
• /
• pp.1-9
• /
• 2008

The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situation including the worst case such as rollover, spin-out and so on. Although the known NHTSA J-turn and Fish-hook steering maneuvers are applied for the vehicle performance assessment, they aren't enough to estimate other possible worst case scenarios. Therefore, it is crucial for us to verify the various worst cases including the existing severe steering maneuvers. This paper includes the procedure to search for other useful worst case based upon the existing worst case scenarios mentioned above and its application in simulation basis. The only human steering angle is selected as a design parameter here and optimized to maximize the index function to be expressed in terms of either roll angle or yaw rate. The obtained scenarios were enough to generate the worst case to meet NHTSA worst case definition (ex.2-inch wheel lift). Additionally, as an application, the worst case steering maneuver is acquired for the vehicle to operate with a simple ESP system. It has been concluded that the new procedure in this paper is adequate to create other feasible worst case scenarios for a vehicle system both with an intelligent safety control system and without it.

• Korean Journal of Hazardous Materials
• /
• v.3 no.1
• /
• pp.52-58
• /
• 2015

Since the HF release in 2012 in Korea, it became one of the most significant to evaluate consequence to the vicinity of industry facilities handling hazardous materials. BTX plant is selected to assess off-site risk to check whether the facility satisfies the Chemical Control Law by Korea Government. Accident scenarios were listed using process safety information. The scenarios having effect to the off-site were selected and assessed further according to guideline provided by Korea government. Worst case and alternative scenarios including other interested scenarios were evaluated using ALOHA. Each evaluated scenario was assessed further considering countermeasures. The results showed that the facility handling chloric acid is safe enough and needed no further protections at the moment.

• Fire Science and Engineering
• /
• v.28 no.5
• /
• pp.14-22
• /
• 2014

Hydrocarbon fires and explosions in petrochemical plants have occurred repeatedly every year. But domestic law of fire protection system is insufficient for the worst case scenario. In this study, we analyzed domestic and foreign standards of fire protection system in petrochemical plants and surveyed firefighting equipment of 32 petrochemical plants in ulsan petrochemical complex. Finally, it is necessary to design fire water supply based on the worst case scenario in petrochemical plants and firefighting equipment such as fixed water spray system, elevated monitor nozzle, water curtain, large amount foam monitor system should be installed for the worst case scenario in petrochemical plants.

• Korean Journal of Hazardous Materials
• /
• v.3 no.1
• /
• pp.59-64
• /
• 2015

Semiconductor industry has large number of chemical inventory and is easily exposed to chemical release incidents. Toxic release is one of the most interested area in evaluating consequence to the vicinity of industry facilities handling hazardous materials. Hydrofluoric acid is one of the typical chemical used in semiconductor facility and is selected and toxic release is evaluated to assess the risk impacted to its off-site. Accident scenarios were listed using process safety information. The scenarios having effect to the off-site were selected and assessed further according to guideline provided by Korea government. Worst case and alternative scenarios including other interested scenarios were evaluated using ALOHA. Each evaluated scenario was assessed further considering countermeasures. The results showed that the facility handling hydroflooric acid is safe enough and needed no further protections at the moment.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2020.11a
• /
• pp.107-108
• /
• 2020

There is a need to analyze various factors in evacuation safety assessment of building in fire. In the current performance based design, evacuation safety assessment in case of fire is being conducted through the simulation as FDS and Pathfinder. However, the location and size of the door, the location of evacuation in the event of a fire are not considered when design. Accordingly, it is difficult to determine the worst case scenario considering the actual fire. Therefore in this study, in this study, we will propose an appropriate evaluation plan through simulation considering the worst-case scenario that may occur in case of fire.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.19 no.6
• /
• pp.30-36
• /
• 2011

The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situation including the worst case such as rollover, spin-out and so on. Although the known NHTSA Sine with dwell steering maneuvers are applied for the vehicle performance assessment, they aren't enough to estimate other possible worst case scenarios. Therefore, it is crucial for us to verify the various worst cases including the existing severe steering maneuvers. This paper includes useful worst case based upon the existing worst case scenarios mentioned above and worst case evaluation for vehicle dynamic controller in simulation basis and UCC HILS. The only human steering angle is selected as a design parameter here and optimized to maximize the index function to be expressed in terms of both yaw rate and side slip angle. The obtained scenarios were enough to generate the worst case to meet NHTSA worst case definition. It has been concluded that the new procedure in this paper is adequate to create other feasible worst case scenarios for a vehicle dynamic control system.

• Journal of Families and Better Life
• /
• v.32 no.3
• /
• pp.99-114
• /
• 2014

The purpose of this study is to investigate the relationship between moral cognitive distortion and peer bullying of children and adolescents. For this study, questionnaires on moral cognitive distortion and peer bullying were administered to 678 students in the 4th, 5th, 7th, 8th, 10th and 11th grades in elementary, middle and high schools located in the metropolitan area of Seoul. The data were analyzed through frequency analysis, mean and standard deviation, t-test, two-way ANOVA, Pearson's correlation and stepwise multiple regression analysis using SPSS Win 12.0. The main findings of this study are as follows: 1) While grade had a significant influence on the moral cognitive distortion of children and adolescents, gender did not. On bullying perpetration and bullying victimization, both gender and grade had a significant influence. 2) Moral cognitive distortion had a significant influence on peer bullying. More specifically, for elementary school students, the variables affecting bullying victimization and bullying perpetration were found to be worst-case-scenario thinking and other-blame thinking, respectively. For middle school students, victimization was affected most significantly by worst-case-scenario thinking, followed by gender; perpetration was most significantly affected by worst-case-scenario thinking. For high school students, victimization was affected most significantly by other-blame thinking, followed by gender; perpetration was most significantly affected by other-blame thinking.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2016.05a
• /
• pp.189-189
• /
• 2016

To generate information that contributes to climate change risk management, it is important to perform a precise assessment on the impact in diverse aspects. Considering this academic necessity, Japanese government launched continuous research project for the climate change impact assessment, and one of the representative project is Program for Risk Information on Climate Change (Sousei Program), Theme D; Precise Impact Assessment on Climate Change (FY2012 ~ FY2016). In this research program, quantitative impact assessments have been doing from a variety of perspectives including natural hazards, water resources, and ecosystems and biodiversity. Especially for the natural hazards aspect, a comprehensive impact assessment has been carried out with the worst-case scenario of typhoons, which cause the most serious weather-related damage in Japan, concerning the frequency and scale of the typhoons as well as accompanying disasters by heavy rainfall, strong winds, high tides, high waves, and landslides. In this presentation, a framework of comprehensive impact assessment with the worst-case scenario under the climate change condition is introduced based on a case study of Theme D in Sousei program There are approx. 25 typhoons annually and around 10 of those approach or make landfall in Japan. The number of typhoons may not change increase in the future, but it is known that a small alteration in the path of a typhoon can have an extremely large impact on the amount of rain and wind Japan receives, and as a result, cause immense damage. Specifically, it is important to assess the impact of a complex disaster including precipitation, strong winds, river overflows, and high tide inundation, simulating how different the damage of Isewan Typhoon (T5915) in 1959 would have been if the typhoon had taken a different path, or how powerful or how much damage it would cause if Isewan Typhoon occurs again in the future when the sea surface water temperature has risen due to climate changes (Pseudo global warming experiment). The research group also predict and assess how the frequency of "100-years return period" disasters and worst-case damage will change in the coming century. As a final goal in this research activity, the natural disaster impact assessment will extend not only Japan but also major rivers in Southeast Asia, with a special focus on floods and inundations.

• Fire Science and Engineering
• /
• v.33 no.4
• /
• pp.112-120
• /
• 2019

Benzene is a class 4 hazardous material according to the Act on the Safety Control of Hazardous Substances. This study qualitatively evaluated the damage size of a "toxic" accident and "pool fire" accidents based on benzene in a virtual scenario of a fire and leakage accident during unloading at a port facility. The KORA program was used as an evaluation method, which is supported as a universal program by the National Institute of Chemical Safety. The range of damage effects of a benzene-induced fire and leakage accident was predicted. In the case of toxic damage range, the accident's damage effect range for the "worst case scenario" was reduced by up to 5.11% with a decrease in the size of the leakage hole. In the case of the leakage time, the damage effect range increased to 145.12% with a 10 min leakage time compared to that of a 5 min leakage time and went up to 20 min (212.29%) with a 20 min leakage time. In the case of pool-fire-induced damage, the damage effect range by radiant heat in the "worst case scenario" was 228.8 m in radius from the center of the handling facility. In the "alternative scenario," the damage effect range by radiant heat was reduced by up to 8.26% compared to that in the "worst case scenario" since the size of the leakage hole was decreased by reducing the cross-sectional area of the pipe.

• Aerospace Engineering and Technology
• /
• v.3 no.2
• /
• pp.42-49
• /
• 2004

Analytical solutions are developed to predict temperature of a satellite box during launch stage under the assumption of worst hot condition. The considered time period is from fairing jettison to separation of satellite during launch stage. After fairing jettison, a box mounted on outer surface of satellite are exposed to space environments such as direct solar flux, Earth IR, Albedo, and free molecular heating. The thermal governing equation is simplified to 1st order ordinary differential equation such that analytic solutions are acquired after the box is assumed as a single lumped mass. The analytical solutions are also available for mass varying box. Finally, the practical application is performed for the case of STSAT-1 launch scenario.