• Interaction and multiscale mechanics
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• v.3 no.4
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• pp.405-414
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• 2010

The performance of full-scale steel and composite bridge safety barriers under vehicle crash is evaluated by using the nonlinear explicit finite element code LS-DYNA. Two types of vehicles used in this study are passenger car and truck, and the performance criteria considered include structural strength and deformation, occupant protection, and post-crash vehicle behavior. It can be concluded that the composite safety barrier satisfies all performance criteria of vehicle crash. Although the steel safety barrier satisfies the performance criteria of occupant protection and post-crash vehicle behavior, it fails to satisfy the performance criterion of deformation. In all performance evaluations, the composite safety barrier exhibits a superior performance in comparing with the steel safety barrier.

• The Journal of the Korea Contents Association
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• v.20 no.6
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• pp.90-98
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• 2020

Modern vehicles are evolving from manual to automatic driving. As the ratio of electrical equipment and software increases inside the vehicle, vehicles that support autonomous driving are becoming another open computer system that can communicate with the outside. The safety of the vehicle means the safety of both the passenger and the non-passenger. It is not clear whether the safety problem of ultimate autonomous vehicles can be solved by the current solution of computer systems related to fault tolerance and security. Autonomous vehicles should not be dangerous to people after they are released to the market, so it is necessary to proactively diagnose all the risks that can be predicted with current technology. This paper examines the current developments of autonomous vehicles and analyzes their dangers that threaten driving safety, as well as their countermeasures.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.6_spc
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• pp.729-735
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• 2016

According to the survey for working environment of the cashiers in highway tollbooths, workers replied that noise was the most harmful substances next to air pollutant in the tollbooth. Researches on the noise levels exposed to cashiers in the highway tollbooth scarcely have been performed. Therefore, the aim of this study was to acquire baseline data to prevent health impairments of the cashiers by evaluating noise level exposed to them. Noise dosimeters were used for monitoring workers' noise exposure level in the tollbooths at 8 different highway tollgates. The noise levels of tollbooths did not exceed noise exposure limit of the ministry of labor, 90 dB(A). The average TWA inside of the tollbooths was 55.4 dB(A) and the average TWA outside of tollbooths was 58.3 dB(A). The average TWA outside of tollbooths was slightly higher than that of inside of tollbooths. However, the significance probability(p-value) was 0.255 which means statistically not significant. The noise levels inside and outside of tollbooth were statistically significant to both mean traffic volume per day and traffic volume of passenger car.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.66-72
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• 2019

To improve ride quality and running stability of high speed train(HST), it is important that connection between coaches adopts the articulated bogies by using a gangway ring, unlike the conventional independent bogies assembled with car bodies. Although the gangway ring should be ensured absolute safety against passenger movement between coaches during train operation, there is still a lack of quantitative durability criteria of that. Therefore, in order to improve the passenger safety of HST, it is important to study the test requirements on durability evaluation for the ring. In this study, seven mixed loading cases were derived from the triaxial loading(vertical/lateral/longitudinal) modes. The safety factor of each component is at least 2.4 or more from the results of the finite element analysis. In addition, fatigue safety was evaluated through durability analysis from the viewpoint of strain-life design. Durability tests for the gangway ring carried out a total of 10 million cycles in 4 phases load conditions. After the durability test, the defect of each component was investigated using nondestructive testing techniques.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.06a
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• pp.125-126
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• 2014

현재의 안전설비기준은 정량적 관점에서 정의되었고, 선박 재난 시나리오에 관한 대응수준을 평가할 방법이 없다. 선박, 특히 여객선 승객의 안전성을 향상시키기 위해서는 설계단계 혹은 증개축단계에서 성능기반의 피난안전설계에 의한 평가를 통해 문제점을 파악하고 개선안을 제실할 필요가 있다.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.336-338
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• 2006

Motorized retractors enhance the safety of passengers by removing the slack of webbing and by holding upright driving position. Reliability of a driving mechanism that includes one-way clutch between the driving motor and webbing is directly linked to the safety of passenger. In this research, conditions for locking one-way clutch and also conditions for sustaining locking are theoretically investigated. the operation of a motorized retractor under realistic conditions is simulated in order to validate the proposed retractor design.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.511-518
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• 1999

Though not very often, a train accident can cause large number of fatality. As a result, public concern about its safety is increasing nowadays. Tn this paper, the structural crashworthiness of Korean High Speed Train trailer was examined through FE analysis. Crash analyses on energy absorbing part and safety zone were carried out to determine each section force. Rollover analysis was performed to observe the amount of intrusion in the passenger's area in case of rollover accident.

• Proceedings of the KSR Conference
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• 2009.05b
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• pp.323-337
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• 2009

This paper researched the adiabatic characteristic, safety and sound insulation characteristic of rolling stock window pane type and transition process of korean train vehicle window glass, and also including investigating a hereafter course of development. The window pane have provided the romantic feeling and the external scenery of train travel to the passenger in period of korea 110 year railway history. From the adiabatic viewpoint, this paper reviewed heat conductivity(U-value) and solar factor according to window pane type, including the safety and sound transmission loss of window pane.

• Journal of Auto-vehicle Safety Association
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• v.8 no.2
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• pp.11-16
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• 2016

The objective of this study was to construct the spring-mass models for the car-to-car offset frontal impact crash. The SISAME software was utilized to extract the spring-mass models using the data from the offset frontal crash test. The spring-mass model of the passenger car could effectively approximate the crash characteristics for the offset frontal barrier impact and the car-to-car offset frontal impact scenarios.

• Journal of Korean Society of Transportation
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• v.35 no.2
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• pp.105-115
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• 2017

Each year, a number of tourists visit Jeju Island, a popular tourist destination in the Republic of Korea. A large portion of the tourists (about 61%) use a rental car as a means of transportation. With this reason, the number of rental cars registered in Jeju was 15,517 in 2011, while the total number of the rental car has rapidly increased to 26,338 in 2015. For the same period, the number of rental car involved traffic accidents has been doubled. Thus, this study aims to analyze the rental car accidents' characteristics, clarifying primary factors related to rental car accidents in Jeju Island. To do this, 918 rental car accidents and 4,201 non-commercial passenger car accidents that occurred in Jeju island over the two years (2014-2015) were compared, using statistical methods such as chi-square test and z-test. The results show that the characteristics of rental car involved accidents are different from those caused by the passenger cars. Most of the rental car accidents in Jeju were caused by young drivers and drivers who had just obtained their driver's licenses. This study finds that driver immaturity, unfamiliar geography, and driving an unfamiliar vehicle are the main causes of the rental car accidents. Statistical analysis confirms that the characteristics of these accidents appeared significantly different from the passenger cars in terms of human and environmental factors. On the other hand, there is no clear evidence that vehicle-related characteristics are different between rental car and non-commercial passenger car accidents. The implications on transportation safety analysis and effective solutions to prevent rental car traffic accidents are discussed.