• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.10 no.5
• /
• pp.1-13
• /
• 2011

Recently, a number of OBU(On Board Unit) have being spreaded since ETCS(Electronic Toll Collection System)using DSRC(Dedicated Short Range Communication) was installed in the tollgate of the whole country. Many R&D and commercialization related to ITS service using DSRC and OBU mentioned above are ongoing such as traffic information collection and provision and a signal control, and public traffic information and management and so on. Especially, there are many researches conducted(conducting) on traffic information collection and provision using communication between OBU and RSE. However, Standards for both DSRC application and traffic collection and provision are not established clearly yet. So we would like to suggest a method of traffic information collection and provision without changing of standard related to DSRC. This method is to put the traffic messages into the existing Action primitive for ETC, which is described on "Technical criterion IV of basic traffic information exchange" which was notified by Ministry of Land, Transport and Maritime Affairs. Proposed standard application method is applied both to RSE and OBE. It is the same system which ETCS used in highway, currently. We confirmed the efficiency and performance of the system through conducting a variety of driving test using 4 vehicles in real road condition. Result of the real road test shows the effectiveness and validity of this method with about 97% communication success rate and based on studying the cases of 3% communication failure, we can analyse the expected problems in traffic information collection and provision using this method.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.24 no.1
• /
• pp.90-95
• /
• 2014

The researchs using brain-computer interface, the new interface system which connect human to macine, have been maded to implement the user-assistance devices for control of wheelchairs or input the characters. In recent researches, there are several trials to implement the speech recognitions system based on the brain wave and attempt to silent communication. In this paper, we studied how to extract features of vowel based on international phonetic alphabet (IPA), as a foundation step for implementing of speech recognition system based on electroencephalogram (EEG). We conducted the 2 step experiments with three healthy male subjects, and first step was speaking imagery with single vowel and second step was imagery with successive two vowels. We selected 32 channels, which include frontal lobe related to thinking and temporal lobe related to speech function, among acquired 64 channels. Eigen value of the signal was used for feature vector and support vector machine (SVM) was used for classification. As a result of first step, we should use over than 10th order of feature vector to analyze the EEG signal of speech and if we used 11th order feature vector, the highest average classification rate was 95.63 % in classification between /a/ and /o/, the lowest average classification rate was 86.85 % with /a/ and /u/. In the second step of the experiments, we studied the difference of speech imaginary signals between single and successive two vowels.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.49 no.7
• /
• pp.1-9
• /
• 2012

In this paper, resistance temperature detector (RTD) integrated into the LED package is proposed in order to solve the temperature dependence of LED's optical properties. To measure the package temperature in real time, the RTD type temperature sensor having excellent accuracy and linearity between temperature change and resistance change was adopted. A stable metallic film is required for long term reliability and stability of the RTD type temperature sensor. Therefore, deposition and annealing condition for the film were determined. Based on the determined condition, the RTD type temperature sensor with the sensitivity of about $1.560{\Omega}/^{\circ}C$ was fabricated inside the LED package. In order to configurate the LED package system keeping the constant brightness regardless of the temperature, additional conversion circuit and control circuit boards were fabricated and added to the fabricated LED package. The proposed system was designed to compensate the light intensity caused by temperature change using the variable duty rate of driving current. As a result, the duty rate of PWM signal which is the output signal of the configurated system was changed with the temperature change, and the duty rate was similarly varied with the target duty rate. Consequently, it was focused the fabricated RTD can be used for compensating the optical properties of LED and the LED package which exhibits constant brightness regardless of the temperature change.

• Journal of the Korean Institute of Telematics and Electronics T
• /
• v.36T no.1
• /
• pp.51-57
• /
• 1999

This thesis is written about the Wired Logic Type Unit in developing equipment that the load is driven, that the interface unit connect with 1 Scan time to PO30 of operated PLC output contact with that a sensing signal of Temperature Sensor RSD Pt $100\Omega$ let generate the relay output of temperature controller and input the PLC. The PLC Test Kit in country that the PLC to be programmed at the PLC education place is able to drive the load, is done to do a education of PLC on status that interface process between PLC and load are disregarded. As Developing Kit for supplement this point, when the relay output of temperature controller to use Pt 100 of temperature sensor as mentioned on the former among every kinds of sensor feed back to the input of the PLC, as the equipment to act with real time system that the output contact of PLC operated to insert the WLTIJ among PC, PLC and the load, it can understand and see very easy the main principle of PLC use. The structure of WLTU to be a interface unit of load separated as to the point of contact and noncontact, sensor, indicating lamp and A contact and B contact that is belong to driving part, and a motor is belong to loading part.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.15 no.1
• /
• pp.53-60
• /
• 2015

Satellite signal is excellent broadband, can provide the same information in a wide range, but there is a disadvantage that much less of the security level of the data. Therefore, supplementation of safety is a serious problem than anything in the satellite communication. In this paper, it was simulated by applying ARIA in encryption technique and by applying transport mode, tunnel mode in security header AH and ESP in order to examine the effect of IPsec VPN. In addition, we had compare with general services that do not apply encryption in order to analyze the impact of the encryption algorithm. Channel, by applying the Markov channel and adding AWGN, is constituted a satellite communication environment. In case of retransmission based error control scheme, we applied Type-II HARQ scheme and Type-III HARQ scheme which are performance is a good way in recently, and it is constituted by a turbo code and BPSK modulation scheme. we were analyzed performance in BER and Throughput in order to compare the simulation more effectively.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.11 no.1
• /
• pp.7-13
• /
• 2006

Linear compressors with a free piston driven by a linear motor are widely attention in the cooling apparatus such as refrigerator due to the high efficiency The stroke of piston in the linear compressor driven by LPMSM (Linear Permanent-Magnet Synchronous Motor) can be obtained from Integrating the input voltage and current of LPMSM, but it may be diverged due to dc components in the voltage and current. The strategy to prevent the divergence of stroke using both the high-pass filter and do offset compensation was suggested. The equations for the magnitude and phase of the stroke and also dc offset including the stroke are derived as a function of the cut-off frequency of HPF. The accurate stroke of a piston can be calculated by compensating for dc offset. The performance of the newly developed stroke calculation scheme has been verified by experimentally on a linear compressor drive system, where the control was implemented by a 16-bit DSP.

• Membrane Journal
• /
• v.21 no.2
• /
• pp.163-170
• /
• 2011

Membrane fouling control in water treatment may be the main obstacle for wider implementation and lower cost. A novel fluorescent spectroscope sensor device for membrane fouling integrity monitoring has been developed and evaluated in this study. PSf membranes for water treatment has been fabricated with three types of organic fluorescent materials, OB, FP, KCB. The fluorescent signal from membrane surface was analyzed throughout the filtration process. It was found that the fluorescent signal due to the membrane fouling decreased and the developed device is reliable for membrane fouling monitoring.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.05a
• /
• pp.653-657
• /
• 2003

Mobile Number Portability means a network capability that users can change service provider while retaining a legacy mobile phone number. Therefore, n provides users with convenience to select service provider comparing service's quality and rate without changing a phone number. in our country, 2G MNP service of QoR method is going to serve in January, 2004. In this paper, We describe connection protocol and NMP procedure between SSP and SCP in order to provide 2G MNP service in domestic network

• Journal of Navigation and Port Research
• /
• v.28 no.6
• /
• pp.497-501
• /
• 2004

In this paper, it is presented a level sensor for measuring a level of the contents of cargo tank using frequency modulated continuous wave(FMCW). The frequency range is 10∼11 GHz, the radar cross section(RCS) of test target is $0.8\textrm{m}^2$ of metal plate. The experiment is performed in laboratory and open ground, the sweep time of the signal is 100 ms, the pyramidal horn antenna of about 22 dBi gain is used, and input power of antenna is about 8 dBm The beat frequency according to the target moving to 40 m is measured. There is a good agreement between measured and calculated results. But the resolution of the FMCW radar is measured about 10 cm due to nonlinear of voltage controlled oscillator(VCO).

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.8
• /
• pp.3610-3616
• /
• 2011

Electrical Railroads provide electric power, which can operate vehicles, via feeder wires. And the supplied current returns to the transformer substation through lines and ground net. The used load current depending on the operation of rail vehicles in the electric railway sections returns to the substation through a track which is a return circuit. The load current contains harmonics because of the power conversion equipment used in rolling stocks and such harmonic currents should not affect train control system. In this paper we present the test result in order to verify that the harmonics produced by the operation of rail vehicles in the newly built electric railway sections can affect interlocking systems. The test in question was performed in a linking section that trackside equipment under railway operating conditions and interlocking are linked in order to identify whether or not the interlocking fitted in a signal machine room can be affected by harmonics according to railway operation.