• International Journal of Railway
• /
• v.3 no.3
• /
• pp.95-105
• /
• 2010

In this paper, a procedure is proposed to optimize bogie suspension parameters in view of minimizing wheel wear produced by curve negotiation, though meeting stability requirements. The problem is dealt with in the form of a constrained minimization problem, in which wheel wear evaluated over a given service scenario is introduced as the cost function to be minimized, and the requirements on vehicle stability are formulated in terms of constraints. The procedure is applied to the case of a non-powered passenger car for high-speed service, and the results obtained are discussed. It is shown that long wheelbase bogie may provide better overall performances than bogies having comparatively short wheelbase. Furthermore, a sensitivity analysis is performed, to define the effect on the optimization results of improving the performances of the yaw dampers in the bogie and of using a different wheel profile.

• Progress in Superconductivity and Cryogenics
• /
• v.9 no.1
• /
• pp.76-81
• /
• 2007

This paper deals with the characteristics of a small scale $high-T_c$ superconducting(HTSC) levitation system. The levitation tester. which models after electrodynamic suspension(EDS) maglev, consists of one HTSC magnet, a reaction plate, and force measuring components. Instead of moving magnet, AC current was applied to the fixed HTSC magnet. The magnet also has persistent current switch(PCS). The inductance of the magnet was 18.5 mH and total joint resistance of the magnet was $5.74{\times}10^{-7}\Omega$. AC current was applied into the HTSC magnet with various frequencies and the levitation force was calculated and measured. According to the increase of the vehicle speed, the levitation force was saturated.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2022.10a
• /
• pp.414-415
• /
• 2022

In this paper, we are going to develop a collision accident prevention technology that automatically recognizes more than 98% of workers and obstacles in 360° around them during work/high-speed movement/cabin rotation, guides collision warning and secures the driver's viewing angle.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38C no.12
• /
• pp.1114-1125
• /
• 2013

License Plate Detection (LPD) is a key component in automatic license plate recognition system. Despite the success of License Plate Recognition (LPR) methods in the past decades, the problem is quite a challenge due to the diversity of plate formats and multiform outdoor illumination conditions during image acquisition. This paper aims at automatical detection of car license plates via image processing techniques. In this paper, we proposed a real-time and robust method for license plate detection using Heuristic Energy Map(HEM). In the vehicle image, the region of license plate contains many components or edges. We obtain the edge energy values of an image by using the box filter and search for the license plate region with high energy values. Using this energy value information or Heuristic Energy Map(HEM), we can easily detect the license plate region from vehicle image with a very high possibilities. The proposed method consists two main steps: Region of Interest (ROI) Detection and License Plate Detection. This method has better performance in speed and accuracy than the most of existing methods used for license plate detection. The proposed method can detect a license plate within 130 milliseconds and its detection rate is 99.2% on a 3.10-GHz Intel Core i3-2100(with 4.00 GB of RAM) personal computer.

• Journal of Institute of Control, Robotics and Systems
• /
• v.17 no.1
• /
• pp.47-53
• /
• 2011

To enable the efficient operation of ITS, it is necessary to collect location data for vehicles on the road. In the case of futuristic transportation systems like ubiquitous transportation and smart highway, a method of data collection that is advanced enough to incorporate road lane recognition is required. To meet this requirement, technology based on radio frequency identification (RFID) has been researched. However, RFID may fail to yield accurate location information during high-speed driving because of the time required for communication between the tag and the reader. Moreover, installing tags across all roads necessarily incurs an enormous cost. One cost-saving alternative currently being researched is to utilize GNSS (global navigation satellite system) carrierbased location information where available. For lane recognition using GNSS, a precise digital map for determining vehicle position by lane is needed in addition to the carrier-based GNSS location data. A "precise digital map" is a map containing the location information of each road lane to enable lane recognition. At present, precise digital maps are being created for lane recognition experiments by measuring the lanes in the test area. However, such work is being carried out through comparison with vehicle driving information, without definitions being established for detailed performance specifications. Therefore, this study analyzes the performance requirements of a precise digital map capable of lane recognition based on the accuracy of GNSS location information and the accuracy of the precise digital map. To analyze the performance of the precise digital map, simulations are carried out. The results show that to have high performance of this system, we need under 0.5m accuracy of the precise digital map.

• Journal of Sensor Science and Technology
• /
• v.26 no.6
• /
• pp.432-437
• /
• 2017

As 4.0 industry has been developed, research on a self-driving car technology and related parts of an automobile has been highly investigated recently. Particularly, a TAS(Torque Angle Sensor) module on steering wheel system has been considered as a key technology because of its precise angle, torque detection and high speed signal processing. The environmental assessment is generally required on the TAS module to examine high resolution of angle/torque detection. In the case of existing TAS module, angle detection errors has been occurred by back-lash on main and sub gear in addition to complicated structure caused by gears. In this paper, a structure of the TAS module, which minimizes the numbers of components and angle detection errors on the module compared with the existing TAS module, for vehicle steering system based on a Multi-track Encoder has been proposed. Also, angle detection signal processing board, and key technology of the TAS module were fabricated and evaluated. As a result of the experiments, we confirmed an excellent performance of the fabricated signal processing board for angle detection and an applicability of the fabricated angle detection board on the TAS module of vehicles by the environmental assessment an automobile standard.

• Journal of the Korean Institute of Telematics and Electronics C
• /
• v.35C no.11
• /
• pp.76-88
• /
• 1998

While most of the research on reinforcement learning assumed a discrete control space, many of the real world control problems need to have continuous output. This can be achieved by using continuous mapping functions for the value and action functions of the reinforcement learning architecture. Two questions arise here however. One is what sort of function representation to use and the other is how to determine the amount of noise for search in action space. The ubiquitous neural network is used here to learn the value and policy functions. Next, the reinforcement predictor that is intended to predict the next reinforcement is introduced that also determines the amount of noise to add to the controller output. The proposed reinforcement learning architecture is found to have a sound on-line learning control performance especially at high-speed road following of high curvature road. Both computer simulation and actual experiments on a test vehicle have been performed and their efficiency and effectiveness has been verified.

• Journal of KIISE:Computing Practices and Letters
• /
• v.16 no.6
• /
• pp.698-701
• /
• 2010

Recently, Vehicular Networks is being developed to provide variety of services such as email, ftp, and video streaming services. As IP mobility technology, Proxy Mobile IP is developed to provide these services for a VANET user. By adopting Proxy Mobile IPv6 (PMIPv6), Vehicular Networks can support IP mobility, but it may cause a proxy binding update (PBU) message when a vehicle moves from one MAG to another. In addition, if the density of vehicles on the road is high, significant PBU messages are generated. In this paper, we propose bulk PBU message to reduce signaling overhead by those PBU messages when a bunch of vehicles move from one MAG to another. When the vehicles move from one MAG to another, it generates only one bulk PBU message to update those vehicle's location. Through numerical and simulation results, we show that our proposed bulk registration reduces signaling overhead when the density of vehicles and the speed of them are high.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.10 no.6
• /
• pp.535-544
• /
• 2017

In this paper, to overcome the limitation of information transmission and reception according to the RF system of UAV, it is necessary to check the position of many UAVs in flight on the basis of mobile communication and to make the LTE modem lightweight and low power And UAVs that are in operation are received and controlled. Through this study, we proposed a method to control real-time location tracking by connecting high-resolution images to the network anytime and anywhere. For this purpose, we propose the requirements and requirements of LTE modem using real-time high-speed data communication technology (3G, 4G LTE, Bluetooth) by presenting the communication module system of LTE-based UAV. N:N control system concept and implementation technology(Control system structure, control data flow chart, flight planning and transmission, real-time location tracking).

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.11
• /
• pp.2751-2757
• /
• 2015

To obtain the system requirement specification in the beginning of the precision guidance and control system development, the effectiveness and reliability analysis for the system are necessary. The main purpose of this research is to obtain the system requirement specification by carrying out the effectiveness analysis using the modeling and simulation(M&S) scheme. M&S model is constructed using 6-DOF dynamic model, environment model, guidanc -navigation & control model. Assume that the navigation sensor is consist of inertial navigation sensor(INS) and doppler velocity log(DVL), and the speed and direction of current is environment parameter. The effectiveness analysis is carried out using circular error probability(CEP) and variance analyze scheme. Also, the effectiveness analysis is utilized for cost-performance analysis considering the cost of commercial INS and DVL sensor. This paper shows the high-level INS and the low-level DVL configure a high price-performance integrated navigation system.