• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.16 no.4
• /
• pp.107-121
• /
• 2017

This study conducted a 3-stage survey and simulation experiment to identify the impact of vehicle platoons on car-following behavior of manually-driven vehicles. Vehicle maneuvering data obtained from driving simulations was statistically analyzed based on three measures including average speed, acceleration noise, and offset to represent the deviation of lateral movements. Results indicate that MV drivers tended to have psychological burden while driving in automated vehicle platooning environments, which resulted in different vehicle maneuvers. It is expected that the outcome of this study would be useful fundamentals in developing various traffic operations strategies for managing mixed traffic stream consisting of MVs and autonomous vehicles.

• Journal of Korea Multimedia Society
• /
• v.16 no.3
• /
• pp.330-335
• /
• 2013

It is expected that the vehicle safety systems using vehicle-to-vehicle communication can reduce the possibility of vehicle collision and prevent the chain crash by promptly delivering the status of neighboring vehicles. Many IEEE 802.11 DCF based Flooding schemes have been proposed, but they may generally expose the problems that the chances of a chain-collision reaction are sharply increased as the vehicle density has increased. Therefore, this paper proposes the chain-collision prevention scheme using a broadcasting-based adaptive report. The proposed method can adaptively allocate the preoccupancy right based on a quantitative priority order and then promptly deliver the warning messages in neighboring areas. Moreover, it is shown from simulation that the proposed scheme provides the performance gains over the existing Flooding based scheme.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.18 no.2
• /
• pp.144-155
• /
• 2019

One of the issues of the automotive industry today is autonomous driving vehicles. In order to achieve level 3 or higher as defined by SAE International, harmonization of autonomous driving technology and connected technology is essential. Current vehicles have new features such as autonomous driving, which not only increases the number of electrical components, but also the amount and complexity of software. As a result, the attack surface, which is the access point of attack, is widening, and software security vulnerabilities are also increasing. However, the reality is that the essential security requirements for vehicles are not defined. In this paper, based on real attacks and vulnerability cases and trends, we identify the assets in the in-vehicle network and derive the threats. We also defined the security requirements and derived essential security requirements that should be applied at least to the safety of the vehicle occupant through risk analysis.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.19 no.6
• /
• pp.134-143
• /
• 2020

With the worldwide spread of African swine fever, interest in livestock epidemics is growing. Livestock transport vehicles are the main cause of the spread of livestock epidemics, but no empirical quarantine procedures and standards related to the mobility of livestock transport vehicles in South Korea. This study extracted livestock-related vehicles' trajectory by utilizing the facility visit history data from the Korea Animal Health Integrated System and the DTG (Digital Tachograph) data from the Korea Transportation Safety Authority and presented them as exposure indexes aggregating the link-time occupancy of each vehicle. As a result, a total of 274,519 livestock-related vehicle trajectories were extracted, and exposure values by link and zone were quantitatively derived. Through this study, it is expected that prior monitoring of livestock transport vehicles and the establishment of post-disaster prevention policies would be provided.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.28 no.6D
• /
• pp.895-904
• /
• 2008

CWR (Continuous Welded Rail) may be broken when a temperature drop below the neutral temperature changes in axial force, causing tensile fracture and rail gap, in winter. Rail-breaks may lead to the damage of the rail and wheel by dynamic load, and the reduction of running safety if not detected before the passage of a train. In this study, the track and train coupled model with open gap for dynamic interaction analysis, is proposed. Linear track and train systems is coupled by the nonlinear Herzian contact spring and the complete system matrices of total track-train system is constructed. And the interaction phenomenon considering open gap, was defined by assigning the irregularity functions between the two sides of a gap. Time history analysis, which have an iteration scheme such as $Newmark-{\beta}$ method based on Modified Newton-Raphson methods, was performed to solve the nonlinear equation. Finally, numerical studies are performed to assess the effect of various parameters of system, apply to various speeds, open gap size and the support stiffness of rail.

• Journal of Platform Technology
• /
• v.11 no.6
• /
• pp.106-115
• /
• 2023

In this paper, we propose a sensor data sharing system for the safe and smooth operation of autonomous vehicles on two-way single lanes in traffic-isolated areas and implement the core module, the situational awareness technology. Two-way single lanes pose challenges for autonomous vehicles, particularly when encountering parked vehicles or oncoming traffic, leading to reversing issues. We introduce a system using infrastructure cameras to detect vehicles' approach, enter, and leave on twoway single lanes in real-time, transmitting this information to autonomous vehicles via V2N communication, thereby expanding the sensing range of the autonomous vehicles. The core part of the proposed system is the situational awareness of the two-way single lane using infrastructure cameras. In this paper, we implement this using object detection and tracking technology. Finally, we validate the implemented situational awareness technology using data collected from actual two-way single lanes.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.14 no.1
• /
• pp.22-30
• /
• 2015

Recently ITS have been increasingly applied on the roads to resolve traffic problems. Especially, Variable Message Sign (VMS), which is the one of ITS for traffic management and traffic safety, can be used for providing information about road conditions, climate conditions. In this study, data acquisition and statistical analysis were conducted for estimating safety impacts of providing traffic information through VMS. As a result of analyzing traffic characteristics before and after providing traffic information through VMS, average travel speed was decreased and vehicles tended to drive on centerline of lanes in 1st and 2nd lane after providing traffic information through VMS. Also, in order to analyze safety impacts of provided VMS traffic information, traffic safety hazard zone was established in each lane and probability distributions of passing traffic on the study area was estimated through Anderson-Darling Test. As a result of this, safety impacts of VMS traffic information in 1st lane could, on average, increase in left and right side of the lane by 0.69% and 7.07%, respectively. In case of 2nd lane, safety impacts could, on average, increase in left and right side of the lane by 2.71% and 0.02%, respectively.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.132-137
• /
• 2011

Many studies are being conducted to improve high speed, light weight and safety of passenger. To improve safety of rolling stock, safety of running performance is most important, and optimizing flow lubrication in driving gear is essential. This study simulates lubricant flow change in driving gear casing which is splashed by the surface of low speed gear teeth following rotational direction of driving gear unit for EMU by using CFD analysis, and based on analysis detail, non-load actual test is conducted for similar driving condition to find out suitability of analysis, selection of lubricate and stability of driving gear.

• Journal of Korean Society of Steel Construction
• /
• v.9 no.2 s.31
• /
• pp.159-169
• /
• 1997

Recently, due to the increasing overloaded heavy vehicles and traffic volumes fatigue failures of steel highway bridges frequently occur. Therefore, it is important to decide rational fatigue design procedure which can reflect lifetime cumulative fatigue damage reasonably. In this study, cumulative fatigue damages are simulated for various bridge systems and traffic conditions. The AASHTO LRFD fatigue design procedure is reviewed and the current fatigue design loading format, in which a single representative truck is loaded regardless of bridge width, is found to yield inconsistent safety level. Improved loading format with rational design load level for fatigue design is suggested.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.10 no.3
• /
• pp.13-20
• /
• 2010

To evaluate the performance of safety apparatus without the full scale crash test, the computer simulation is inevitable. But, to improve the accuracy of computer simulation, it is important to reasonably determine the input parameters in which the interaction of vehicle-guardrail-soil should be accounted for. This study is focused on how to enhance the reliance of the dynamic performance of guardrail obtained by computer simulation. Analyses were done on the sensitivity of output variables to the change of input parameters by using BARRIER VII of which the usefulness was proved on the barrier-vehicle impact analysis. Through the analyses important input parameters, which give sensitive effects to output of computer simulation, are found out, and methods to determine such parameters are suggested to improve the accuracy of simulation.