• Proceedings of the KSR Conference
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• 2005.11a
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• pp.146-151
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• 2005

Main parameters of wheel-rail combination are investigated by profile analysis. A rolling radius difference is one of the main characteristics that describe a contact between wheelset and railway track, which in turn defines the dynamic behavior of a wheelset. This paper describes functional relation between lateral wheelset displacement and rolling radius difference or conicity on new/worn wheel of existing narrow gauge vehicle. Information about curving behavior and running stability are given by this both relations. The optimal wheel profile for railway vehicle with narrow gauge is adopted through this analysis. And, the applicable limit value of conicity which is used in order to do dynamic simulation of vehicle is presented.

• Asia pacific journal of information systems
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• v.31 no.3
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• pp.378-391
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• 2021

The low use of e-vehicles in Yogyakarta City and Pekanbaru City is an essential issue for local governments to maximize e-government policies in both regions. The purpose of this research is to analyze people's attitudes and factors influencing the community of e-Samsat (e-Vehicle tax) users in developing the UMEGA theory, namely technology and government trust. This is a quantitative research based on the philosophy of positivism, which is used to examine populations and individual samples. Data were collected using research instruments and quantitatively analyzed. Furthermore, the hypothesis of the obtained data was tested using SEM-PLS. The results showed that social influence does not affect attitudes of e-Samsat (e-Vehicle tax) users. Furthermore, the study showed that the development of umega theory by adding variables of trust in technology and government affects people's behavior in using e-Samsat services.

• Journal of the Korean Society of Safety
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• v.23 no.2
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• pp.45-50
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• 2008

The purpose of the present study was to investigate the age difference in driving behavior(more specifically, left-turn). The participants were instructed to report whether they can turn left their car in the T-shape road(road and other vehicles' behavior relating to driver's tasks were recorded in advance and projected the simulation screen) after the leading vehicle passed them(i.e., before the target vehicle arrived). The participants' judgment accuracy and response bias were analyzed by using signal detection theory. The results showed that the old group tended to be less sensitive but more confident in their judgement of turning left their car. In particular, both age groups appeared to more depend on the distance from observation location to approaching vehicle rather than arrival times or driving speeds of the approaching vehicle.

• Journal of Auto-vehicle Safety Association
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• v.15 no.4
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• pp.95-101
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• 2023

As the popularization of autonomous vehicles is anticipated, it is expected that the variety of passenger postures will diversify. However, the current vehicle safety system is expected to be inadequate for accommodating these diverse passenger postures, particularly in reclined positions where severe injuries have been reported in frontal collisions. Therefore, it is necessary to investigate the biomechanical responses and tolerances of occupants in reclined postures. In this study, the behavior and injuries of a Hybrid-III dummy model in a reclined position are analyzed through frontal collision sled simulations equipped with the semi-rigid seat provided by the previous study, three-point safety belt with pretensioner and load limiter, and airbag models. The results are evaluated by comparing thouse reponses with post-mortem human surrogate (PMHS) data, and the findings are expected to be applicable to the basic design of a new restraint system suitable for various postures in autonomous vehicles.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.4
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• pp.353-360
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• 2010

A skid-steering method which applied to the various mobile robot platforms currently shows its effectiveness in the specified field areas and purposes. This system contains however, several problems of its intrinsic properties such as slippages occurred by different moving direction between vehicle's driving and wheel's rotary and difficulties of driving performance control and so on. This paper deals with the suggestion of suitable control algorithm for 6WD/6WS skid steering wheeled vehicle and verified its feasibility by analyzing the behavior of 6WD/6WS skid-steered wheeled vehicle model and by applying the engineering analytical method to the considered mobile platform. The Performance of vehicle model is evaluated by using slip mode control to follow the steering input and, as a future work, this control algorithm could be applied to real 6WD/6WS in-wheel drive type vehicle finally.

• Journal of Ocean Engineering and Technology
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• v.19 no.3
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• pp.31-38
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• 2005

Ocean developments gradually move to deep-sea in the 21 century. A deep-sea unmanned underwater vehicle is one of important tools for ocean resource survey. A marine cable plays an important role for the safe operation and signal transmission of a deep-sea unmanned underwater vehicle. The umbilical cable of a deep-sea unmanned underwater vehicle is excited by surface vessel motion and shows non-linear dynamic behaviors. A numerical method is necessary for analysing the dynamic behavior of a marine cable. In this study, a numerical program is established based on a finite difference method. The program is appled to 6000m long cable for a deep-sea unmanned underwater vehicle and shows good reasonable results.

• Earthquakes and Structures
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• v.18 no.1
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• pp.1-14
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• 2020

The vehicle-bridge interaction (VBI) analysis might be cumbersome and computationally expensive in bridge engineering due to the necessity of solving large number of coupled system of equations. However, VBI analysis can provide valuable insights into the dynamic behavior of highway bridges under specific loading conditions. Hence, this paper presents a numerical study on the dynamic behavior of a conventional highway bridge under strong near-field and far-field earthquake motions considering the VBI effects. A recursive substructuring method, which enables solving bridge and vehicle equations of motion separately and suitable to be adapted to general purpose finite element softwares, was used. A thorough analysis that provides valuable information about the effect of various traffic conditions, vehicle velocity, road roughness and effect of soil conditions under far-field and near-field strong earthquake motions has been presented. A real-life concrete highway bridge was chosen for numerical demonstrations. In addition, sprung mass models of vehicles consist of conventional truck and car models were created using physical and dynamic properties adopted from literature. Various scenarios, of which the results may help to highlight the different aspects of the dynamic response of concrete highway bridges under strong earthquakes, have been considered.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.11
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• pp.5322-5342
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• 2016

In vehicle-to-vehicle (V2V) networks, where selfishness degrades node activity, countermeasures for collaboration enforcement must be provided to enable application of a sage and efficient network environment. Because vehicular networks feature both high mobility and various topologies, selfish behavior judgment and establishment of a stable routing protocol become intensely challenging. In this paper, a two-phase-based generous cooperative routing protocol (called GEC) is presented for V2V networks to provide resistance to selfishness. To detect selfish behaving vehicles, a packet forwarding watchdog and an average connection rate based on the multipath weight method are used, where evidence is gathered from different watchdogs. Then, multihop relay decisions are made using a generous cooperative algorithm based on game theory. Finally, through buffering of the multiple end-to-end paths and judicious choice of optimal cooperative routes, route maintenance phase is capable of dealing with congestion and rapidly exchanging traffic. Specifically, it is proved that the GEC is theoretically subgame perfect. Simulation results show that for V2V networks with inherently selfish nodes, the proposed method isolates uncooperative vehicles and is capable of accommodating both the mobility and congestion circumstances by facilitating information dissemination and reducing end-to-end delay.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1160-1165
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• 2008

The development of a new railway vehicle is under progress through the Next Generation High-Speed Rail Development Project in Korea. Its aim is to develope fundamental technology of the vehicle that can run over 400km/h. The new distributed traction bogie system, 'HEMU'(High-speed Electric Multiple Unit), will be used and is different from previously developed high speed railway vehicles. Previous vehicles adopted push-pull type system, which means one traction-car drives rest of the vehicle. Due to the difference, investigation on dynamic behavior and its safety evaluation are necessary, as a part of verification of the design specification. In this paper, current progresses of researches are presented. And the High-Speed Railway vehicle system is evaluated for a dynamic characteristic simulation. Proper models including air-suspension system, wheel-rail, bogie and car-body will be developed according to the vehicle simulation scenario. International safety standard will be applied for final verification of the system. This research can propose a better solution when test running shows a problem in the parts and elements. Finally, the vehicle that has excellent performance will be developed, promoting academic achievement and technical development.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.4
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• pp.165-172
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• 2014

When a vehicle is running on the road, the surface conditions and environment of road by reason of insufficient road design standards is so greatly that have an effect on drivers. In particular, the road design of the past is conducted empirical and ideal judgment, but recently, the new technical development is attempted that three and four dimensional parameters is reconsidering and adjusting at the same time. In this study, we analyzed the vehicle behavior characteristics according to the change of driving speed and vertical grades on braking at the peak point of the frozen road by using a PC-crash program for traffic accident reconstruction. As a result, we were conformed the fact that the friction coefficient of road surface and the vehicle speed is affected by vehicle behavior characteristics for intersection vertical grades and were showed the feasibility of verification through a simulation in order to solve the problem of road design in advance.