• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11B
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• pp.1389-1393
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• 2011

In this paper, we implement the VLC system based on CAN communication which is usually used in car, plane, ship, product line control system, medical device and industrial device. We implement the application circuit which is VLC and CAN communication and explain the principle. Circuit's pulse features are demonstrated by each part's signal. Total communication distance is 3m and it's transmission performance is error free.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.622-624
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• 2014

A maglev train records a host of physical variables such as gaps, voltages and currents for suspension control and monitoring purposes. These data available from a maglev contains wealth of information that can be explored for various uses. One possible of such application is to use the gap data to estimate the shape of the rail, especially at the joints where rails are connected. The eddy current sensors that measure the gap between the rail and the car body produce large peaks around the joints. The suspension controller discards these peaks. Since the shape of the peaks is related to the joint, however, these peaks can be utilized to estimate the shape of the joints. In this paper, we present preliminary results on estimating the joint shape using the peak data. The results show that the approach is promising, albeit several technical difficulties to overcome.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.5
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• pp.209-213
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• 2010

This paper is a study of Car safety network system using sensed data from varied sensors. This hardware will work with various sensors and communication protocols. There are many sensors. Then, I selected 3 sensors for test, which were sonic sensor for distance checking, tilt sensor for rollover and impact sensor for car accident and theft. Also, there are many interfaces for sensor. Therefore I designed hardware to support various sensor interfaces. For instance ADC(Analog to Digital converter), I2C, RS232, RS485, CAN. In this case, sonic sensor have I2C interface, tilt sensor have RS485 interface and Impact sensor have analog interface. In this research, I can gather sensing data from 3 sensors (mentioned above), and sending control signal to other processor with RS232, RS485, CAN communication. So, we can use easily this hardware for many cases of systems, which need sensors.

• 전자공학회논문지 IE
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• v.44 no.4
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• pp.1-10
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• 2007

In this thesis, we study the implementation of hands-free phone in a car, taking acoustic echo canceller, in order to remove acoustic echo effectively. Conventional coustic echo canceller used for only adaptive filtering has much difficulty to solve both echo and double-talk problem. To tackle this problem, we propose acoustic echo canceller consisting of adaptive filter using a modified NLMS, VAD to catch exact voice activity duration using two independent forgetting factors, double-talk detector to detect fast and precise double talk duration using cross-correlation between microphone signal and residual echo, and output controller using VAD and double-talk detector. The proposed hands-free phone taking acoustic echo canceller shows the performance that has not acoustic echo and guarantees full duplex.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.9 s.351
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• pp.80-87
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• 2006

In this paper, we analyze the performance of IEEE 802.11b WLAN communication between access point(AP) and mobile equipment(ME) in 2.4 GHz band with noise and interference factors. WLAN communication at in-vehicle environment is assumed as the communication between main vehicle controller and electronic device such as sensor, ECU (Electrical Control Unit) in vehicle on telematics field for implementing wireless vehicle control system. Received interference level from other system's mobile equipment in the same band and automobile noise from each part of vehicle can be the main factors that can cause increasing error rate of control signal. With these (actors, we focus on the Eb/No the BER performance of WLAN for analyzing the characteristic of interference factors by the measured bit error rate.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.8
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• pp.758-769
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• 1991

We have investigaed the radio data system which is used for the VHF/FM streo broadcasting system. The RDS system has the I6 important service features which is given by the digital multiplexed modulation method above the FM stereo baseband spectrum. The related cicuit system and general-purpose micro-controller have been applicated for the demodulation and processing of transmitted digital information at the rate of 1187.5bps, and we have developed the receiver system which performs the primary 5 features. The develpoed system has the complete compatibility with the conventional FM-car stereo receiver, we have analyzed the received RDS signal via the hardware implementation.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.6
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• pp.29-37
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• 1994

Active noise control of random noise which propatate in the vehicle cabin as a form of spherical wave is the target of this study. In the previous study, the adaptive algorithm for adaptive controller is presented for the application in active noise control system. And for the preliminary study of adaptive active noise control in vehicle cabin as a real system, a computer simulation is performed on the effectiveness of the adaptive algorithm in the amplitude of the pressure fluctuation. This work studies the implementation of multi-channel feedforward adaptive algorithm for the reduction of the noise inside a vehicle cabin using a number of secondary sources derived by adaptive filtering of reference noise source. Multi-channel adaptive feedforward algorithm are verified in numerical simulation and semi-experimental justification of developed system is made on a domestic passenger car. In the results of semi-experimental study, the noise of specific region in the interior of automobile are reduced for the appreciabe sound pressure level in the operating engine rpm and finally this study suggests the capabilities of the real time active noise control in 3 dimensional acoustic fields.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.5
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• pp.173-177
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• 2016

Korea, the traffic and transportation problems are significant because private cars are increasing constantly. Therefore, it is imperative to improve traffic condition so as to solve the problems such as traffic congestion and accidents which may occur due to the increase of vehicles in a limited area through the signal control. However, the current operating system for traffic control cannot provide car users the optimal signal but it generates a time delay of vehicles, traffic congestions etc. In this paper, we propose and implement the system based on V2X based automatic controller, which reduces the waste of time and the driver's psychological stress on the road intersection.

• Journal of Korean Society of Transportation
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• v.18 no.5
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• pp.57-67
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• 2000

Two fuzzy travel time estimators for interrupted traffic flow were developed based on field survey data and simulation data 7hat is collected from DETSIM, which is microscopic traffic simulation model that car-following theory is applied. One is FETTOS(Fuzzy Estimator of Travel Time using Occupancy and Spot speed) and the other is FETTOS(Fuzzy Estimator of Travel Speed using Volume and Occupancy). Fuzzy logic controller was applied to the estimators to deal with non-linear relationship between traffic variables and travel time. According to results of simulation and field survey. estimation of travel time can be modeled by using percent occupancy better than any other traffic variables. Detector location from storyline and signal timing Plan of intersection are affected to estimate travel time. With a few findings, the estimator was constructed and its performance was tested for observed travel time data and simulated data. FETTOS which needs signal timing plan and detector location estimates travel time with accurate better than FETSVO does. However. FETSVO has excellent transferability because the estimator needs set of input data only; volume and time mean speed.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.6
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• pp.271-280
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• 2017

In this paper, we propose a new safety system composed of wearable devices, driver's seat belt, and integrating controllers. The wearable device and driver's seat belt capture driver's biological information, while the integrating controller analyzes captured signal to alarm the driver or directly control the car appropriately according to the status of the driver. Previous studies regarding driver's safety from driver's seat, steering wheel, or facial camera to capture driver's physiological signal and facial information had difficulties in gathering accurate and continuous signals because the sensors required the upright posture of the driver. Utilizing wearable sensors, however, our proposed system can obtain continuous and highly accurate signals compared to the previous researches. Our advanced wearable apparatus features a sensor that measures the heart rate, skin conductivity, and skin temperature and applies filters to eliminate the noise generated by the automobile. Moreover, the acceleration sensor and the gyro sensor in our wearable device enable the reduction of the measurement errors. Based on the collected bio-signals, the criteria for identifying the driver's condition were presented. The accredited certification body has verified that the devices has the accuracy of the level of medical care. The laboratory test and the real automobile test demonstrate that our proposed system is good for the measurement of the driver's condition.