• Journal of Auto-vehicle Safety Association
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• v.14 no.3
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• pp.48-59
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• 2022

A V2X system can be a candidate as a means to increase the stability of autonomous vehicles. In particular, in order to implement a Level 4 or higher autonomous driving system, the application of the V2X system is essential. Wireless communication technologies applicable to the V2X system include WAVE and C-V2X. Currently, the V2X service most used by autonomous driving systems is a service that provides signal phase and timing information and since real-time characteristic is a very important, verification of this service must be done. In this paper, we measured the time delay characteristics for providing signal phase and timing information using WAVE and LTE communication, and proposed a TOD-based signal phase and timing information generation method without using V2X communication system. To analyze the time delay characteristics, RTT (Round Trip Time) was measured as a result of the measurement. Average RTT using WAVE communication was 5.84ms and was 104.15ms with LTE communication. As a result of measuring the error between the signal phase and timing information generated based on TOD and the actual traffic light state, it was measured to be -0.284~3.784sec.

• Journal of Auto-vehicle Safety Association
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• v.14 no.4
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• pp.91-99
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• 2022

In Korea, various studies on autonomous vehicles are being conducted with the aim of commercializing the fully autonomous driving (Lv.4) on major roads in 2027. Currently, the communication between non-autonomous vehicles and road users is made with gestures, eye contact, and verbal signals. In the case of autonomous vehicles in the future, autonomous vehicles should communicate instead of drivers. Recently, V2H communication technology (communication technology between autonomous vehicles and road users) is being developed. This study shows technology priorities using the KANO model in caution (warning) and traffic (concession) situations. As a result, a total of six attractive quality technologies were analyzed: technology to provide dark warning information in a display graphic; technology to provide dark warning information in a projection graphic; technology to provide light concession information in a display graphic; technology to provide dark concession information in a display graphic. In the future, it will investigate the preference of users in providing V2H information by road situation. It will be used as a V2H design priority.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.4
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• pp.325-336
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• 2013

FlashLinQ, one of the typical D2D communication systems developed by Qualcomm, considers a single-tone communication based distributed channel-aware link scheduling method to realize the link scheduling process with low control overheads. However, considering the frequency selective fading effect of practical multi-path channel, the single-tone based SIR estimation causes a critical scheduling error problem because the received single-tone signal has quite different channel gain at each sub-carrier location. In order to overcome this problem, we propose a novel link scheduling method based on CAZAC (Constant Amplitude Zero Auto-Correlation) sequence for D2D communication system. In the proposed method, each link has a unique offset value set for the generation of CAZAC sequences. CAZAC sequences with the cyclic offsets are transmitted using multiple sub-blocks in the entire bandwidth, and then each device can obtain nearly full-band SIR using a good cyclic cross-correlation property of CAZAC sequence.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.2 no.2
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• pp.231-239
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• 1998

In this paper, we designed a current controlling servo system for speed control of a PMSM. In existing auto-tuning methods for PI controller parameters, the output response is delayed and the overshoot is generated. By solving these existing problems in this paper, a new PI auto-tuning method is applied to the speed controller for fast-response and reduced overshoot. PMSM servo systems offer a great advantage in unmanned factories where a great number of servo motors are employed, because of its easy maintenance characteristics and controllability. The implemented servo system is composed of absolute position detecting circuits of a rotor, a new auto-tuning PI control algorithm, a speed controller by using DSP, and power driving section. The proposed servo system is verified for it's practical availability by considering experimental results.

• Journal of Sensor Science and Technology
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• v.22 no.1
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• pp.65-70
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• 2013

The integrated sensor module of vehicle combines the functions of rain sensor, auto defog sensor, and sun angle sensor into a single module. These functions originally were applied to work separatively. This integrated sensor module should meet the each performance which appears from the individual modules up to the same level or higher. Therefore, it is important to verify the stability and the accuracy considering the characteristics of the integrated sensor module according to various situations. For the verification, we need to use the actual data of integrated sensor module measured but, a lot of time and money is needed to collect data measured under various circumstances when operating. Thus, through the development of this simulator for the control of the integrated sensor module, we can use it effectively for the initial verification of integrated sensor module by implementing the various situations. In this paper, the simulator for controlling the integrated sensor module which combines vision-based rain sensor, auto defog sensor, auto light sensor, and sun angle sensor has been developed.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.11
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• pp.1101-1106
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• 2016

In this thesis, I developed a ball press pushing up equipment to solve the defect that occurs when the ball is inserted to the auto transmission. The ball press pushing up equipment is composed of heating device, thermostat which controls the heating device and the automated insertion device which helps to enhance mass production. This development contributes to quality improvement of domestic automobile production auto transmission part, and also contribute to cost reduction and sales increase for corporations.

• Journal of Auto-vehicle Safety Association
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• v.8 no.2
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• pp.17-23
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• 2016

Construction of our machine "Digital Tacho Graph" toghether with development and intergrated management system information is attached under Traffic Safety Law in article submission. This machine "Digital Tach Graph" has been mandated on a priority basis. The entire machine is constructed with specialised components to collect data that can retrive basic information. To obtain the components to perfect the information to optimize the device and system.

• Journal of Satellite, Information and Communications
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• v.7 no.1
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• pp.21-26
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• 2012

For the last 20 years, our country has been pointing to a great power for digital information technology, but quantum information technology which is already researched in many forefront nations lags significantly behind other countries. Recently, quantum information management, quantum computing and quantum communication based on the quantum mechanics have been researching actively in many fields such as cryptology. On the basis of these background, in this paper, to efficient data transmission and detection for quantum data, we apply the orthogonal sequence to quantum communication system. The performance of proposed scheme is analyzed in terms of auto and cross correlation performance.

• Journal of Auto-vehicle Safety Association
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• v.14 no.2
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• pp.70-74
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• 2022

This paper describes the development of a target vehicle state estimation algorithm using vehicle-to-vehicle (V2V) communication. Perceiving the state of the target vehicle has great importance for successful autonomous driving and has been studied using various sensors and methods for many years. V2V communication has advantage of not being constrained by surrounding circumstances relative to other sensors. In this paper, we adopt the V2V signal for estimating the target vehicle state. Since applying only the V2V signal is improper by its low frequency and latency, the signal is used as additional measured data to improve the estimation accuracy. We estimate the target vehicle state using Extended Kalman filter (EKF); a point mass model was utilized in process update to predict the state of next step. The process update is followed by measurement update when ego vehicle receives V2V information. The proposed study evaluated state estimation by comparing input V2V information in an experiment where the ego vehicle follows the target vehicle behind it.

• Journal of Auto-vehicle Safety Association
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• v.15 no.4
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• pp.16-22
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• 2023

This paper presents a proactive longitudinal motion planning algorithm for improving the safety of an automated bus. Since the field of view (FOV) of the autonomous vehicle was limited depending on onboard sensors' performance and surrounding environments, it was necessary to implement vehicle-to-vehicle (V2V) communication for overcoming the limitation. After a virtual V2V-equipped target was constructed considering information obtained from V2V communication, the reference motion of the ego vehicle was determined by considering the state of both the V2V-equipped target and the sensor-detected target. Model predictive control (MPC) was implemented to calculate the optimal motion considering the reference motion and the chance constraint, which was deduced from manual driving data. The improvement in driving safety was confirmed through vehicle tests along actual urban roads.