• Transactions of the Korean Society of Automotive Engineers
• /
• v.6 no.5
• /
• pp.222-227
• /
• 1998

Collision warning systems have been an active research and development area as the interests and demands for ASV's (Advanced Safety Vehicles) have increased. This paper presents an experimental investigation of a collision warning system for automobiles. A collision warning HiLS(Hardware-in-the-Loop Simulation) system has been designed and used to test the collision warning algorithm, radar sensors, and warning displays under realistic operating conditions in the laboratory. the collision warning algorithm is operated by a warning index, which is a function of the warning distance and the braking distance. The computer calculates velocities of the preceding vehicle and following vehicle, relative distance and relative velocity of the vehicles using vehicle simulation models. The relative distance and the relative velocity are applied to the vehicle simulator controlled by a DC motor.

• Journal of ILASS-Korea
• /
• v.13 no.4
• /
• pp.187-192
• /
• 2008

In this study, the mechanisms of binary droplet collision were studied with diesel, ethanol and purified water. The droplet collisions of liquid droplet have been investigated for the same droplet diameter. In order to obtain the digital images of the droplet collision behavior, the experimental equipment was composed of the droplet generating system and the droplet visualization system. The droplets were produced by the vibrating orifice monodisperse generator. The visualization system consisted of a long distance microscope, a light source, and a high speed camera. The outcomes of binary droplet collision can be divided into four regimes, bouncing, coalescence, reflexive separation and stretching separation. The impact angle and the relative velocity of binary droplet are main parameters of collision phenomena, so the transition mechanism of droplet collision can be divided by the impact parameter.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.3
• /
• pp.139-150
• /
• 2000

Although a number of neck injuries are generated, the data which quantify the kinematic response of the human head and cervical spine in low-speed rear-end automobile collisions is very limited. On this problem, just few in vitro experimental research or some experimental research using dummy on neck injury by rear-end collision was conducted, thus systematic research is requested on full scale injury mechanism. An occupant model for the response of the occupant subject to rear-end collision using commercial dynamics package DADS was developed. Developed model shows more close agreement with the experimental data compared with the MADYMO simulation results for the cases of ${\delta}V=16$ kph in sled test. For the case of ${\delta}V=8$ kph and 33.5 kph with production seat, model also shows its reliable response compared with experimental results using Hybrid III and Hybird III with RID.

• Journal of ILASS-Korea
• /
• v.22 no.3
• /
• pp.129-136
• /
• 2017

Effects of collision angle on heat transfer characteristics of a liquid droplet impinging on a heated wall above the Leidenfrost point temperature were experimentally investigated. The heated wall and droplet temperatures were $506^{\circ}C$ and $100^{\circ}C$, respectively, and the impact angle varied from $20^{\circ}$ to $90^{\circ}$ while the normal collision velocity was constant at 0.27 m/s. The droplet collision behaviors and the surface temperature distribution were measured using synchronized high-speed video and infrared cameras. The major physical parameters influencing upon droplet-wall collision heat transfer, such as residence time, wall heat flux, effective heat transfer area, heat transfer amount, were analyzed. It was found at the constant normal collision velocity that the residence time, wall heat flux and effective heat transfer area were hardly not changed, resulting in the almost constant heat transfer amount.

• 한국전산유체공학회:학술대회논문집
• /
• 2008.03b
• /
• pp.320-323
• /
• 2008

In this study the effect of collision model was evaluated in spray field by CFD. A collision is basically the interaction between droplets and criteria of collision is determined by drop Weber number, impact parameter, and drop-size ratio. Early developed collision model considered coalescence and grazing collision with the exchange of momentum. However in experimental research there were bouncing, coalescence, reflexive separating and stretching separating in interaction between droplets. In this study the collision considering such complex phenomena is modeled and was compared with the basic collision model.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.36 no.3B
• /
• pp.248-253
• /
• 2011

Collision avoidance algorithm of vessels have been studied to avoid collision and grounding of a vessel due to human error. In this paper, We propose a collision avoidance algorithm using bayesian estimation theory for safety sailing and reduced risk of collision accident. We calculate collision risk for efficient collision avoidance using bayesian algorithm and determined the safest and most effective collision risk is predicted by using re-planned with re-evaluated collision risk in the future(t=t'). Others ship position is assumed to be informed from AIS. Experimental results show that we estimate the safest and most effective collision risk.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.3
• /
• pp.1802-1819
• /
• 2017

Correlation-enhanced collision attack has been proposed by Moradi et al. for several years. However, in practical operations, this method costs lots of time on trace acquisition, storage and averaging due to its bytewise collision detection. In this paper, we propose a bitwise collision attack based on second-order distance model. In this method, only 9 average traces are enough to finish a collision attack. Furthermore, two candidate models are given in this study to distinguish collisions, and the corresponding practical experiments are also performed. The experimental results indicate that the operation time of our attack is only 8% of that of correlation-enhanced collision attack, when the two success rates are both above 0.9.

• Journal of the Korea Society of Computer and Information
• /
• v.11 no.3
• /
• pp.187-192
• /
• 2006

We reviewed the collision event with pc-based shooting games and existing collision detection algorithms. Then we proposed a new collision check technique using a small quadrilateral unit. by which existing quadrilateral collision detection techniques can be made up for. For demonstration we implemented a simple shooting game having its screen output. We proved that the proposed technique can be applied to real computer games by means of showing the experimental results and screen outputs from implemented real games.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2004.04a
• /
• pp.169-176
• /
• 2004

Offshore structure crossing navigation waterways must not only be designed to resist gravity, wind, and earthquake load, but also be capable of resisting ship and barge collision load. Current specifications for offshore structure design provide empirical relationships for computing impact loads generated during barge collision, however, these relationships are based on the limited experimental data. In this paper, the dynamic finite element analysis is used to computing force for vessel collision scenarios to offshore structures. Results obtained from the ANSYS/LS-DYNA are compared to AASHTO bridge design specifications.

• Journal of Institute of Control, Robotics and Systems
• /
• v.16 no.3
• /
• pp.233-238
• /
• 2010

This paper describes a multi-mobile robot system with fuzzy rule based structure in collision avoidance. Collision avoidance is an important function to perform a given task collaboratively and cooperatively in multi-mobile robot environments. So the important but challenging problem is handled in this paper. Considered obstacles for collision avoidance between multi mobile robots are static, dynamic, or both of them at the same time. Using the fuzzy rule based structure, distance and angle from a robot to obstacles are described as fuzzy linguistic values and steering angle for the robot are updated from the collision environments. As a result, the multi-mobile robot can modify a global path from a robot itself to its own target. In addition, avoiding collision with static or dynamic obstacles for the robot system can be achieved. Simulation based experimental results are given to show usefulness of this method.