• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.1145-1150
• /
• 2008

In this paper, We studied efficient design of wireless transmission system for unified data transmission in a subway and railway. It is increased that need of broadband multimedia service to make useful environment for user and to support the operation of railway system. High bandwidth is better if we need more services. But, high bandwidth requires more cost at tunnel of subway. More bandwidth make receive sensitivity to bad. So it need more wireless Station. We deduced best bandwidth of subway wireless transmission system reflecting the cost of installation and efficiency of system. Consequently, we decide efficient service model of broadband wireless system at a subway. Subway broadband wireless transmission system is tested in this year, and it is to be extended to province subway. Cost of subway broadband wireless transmission system is saved, because the system can be efficiently designed. Therefore, the effectiveness is expected to be very big.

• 한국정보통신설비학회:학술대회논문집
• /
• 2009.08a
• /
• pp.219-220
• /
• 2009

Many surveillance cameras used in security system are controlled with RS-485 communication protocol. In this situation, if RS-485 connection can be replaced with wireless connection using sensor network technology, an installation will become ease because of no wired connection and also a deployment of cameras will become free. This paper explains about the design of wireless sensor node and the necessary implementation for an operation, which can be replacing RS-485 connection for the development of CCTV control system based on wireless sensor network. The hardware platform of sensor node was designed based on MicaZ and the software was developed based on TinyOS. To control surveillance cameras deployed on wide area, the supporting of multi-hop also was implemented. With the result of experiment deploying on real environment, it was revealed that the controller could control cameras quickly with wireless.

• Proceedings of the KSR Conference
• /
• 2008.11b
• /
• pp.1344-1353
• /
• 2008

The trend is that the wireless communication system, which has specific characteristics ; low cost & limitation for installation, has been developed more actively than the wire communication system. Therefore, the communication system has been changed from the wire system with an optical cable to the wireless system in the various field of life. In the railroad field, lots of researches on the wireless communication system for the safety of infrastructure and the convenience of passenger have been conducted. The WSN(Wireless Sensor Network), which means same concept with USN(Ubiquitous Sensor Network), pursues the ubiquitous environment which means user can access network at anywhere and anytime. In this paper, the wireless communication technologies which are suitable for the WSN of subway station were investigated and the best solution of WSN was suggested.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.27 no.10
• /
• pp.101-106
• /
• 2013

This paper proposes the new high precision monitoring sensor for the Marine Installation. Among variety of sensor network systems, wireless information transmission through the marine is one of the enabling technologies for the development of future marine-observation systems and sensor networks. Applications of marine monitoring range from oil industry to aquaculture, and include instrument monitoring, pollution control, climate recording, prediction of natural disturbances. For these marine applications to be available, however, the provision of precise location information using monitoring sensor is essential. In this paper, the dynamic characteristics for obtaining the location information of monitoring sensor is analyzed. The theoretical and experimental studies have been carried out. The presented results from the above investigation show considerably excellent performance for the Monitoring for the Marine Installation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.9
• /
• pp.86-93
• /
• 2011

The necessity of Power Quality(PQ) Management grow bigger because the disturbance strength in power system is increasing, on the other hand, the tolerance of electrical components is reducing with widely use of the IT and digital equipments. The domestic management standards on power quality are enacted based on the IEC standards in recent. Since the IEC standards defines the measurement and evaluation point on PQ as PCC(Point of Common Coupling) which is normally the point of penetration between customer and power company, the PQ monitoring system(PQMS) should be made to measure and manage the PQ of custom effectively. In this paper, therefore, the economical construction plan on PQMS using the wireless communication channel in distribution automation system is suggested, and the usefulness of the PQMS are shown by analyzing the PQM data with IEC standards.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2005.05a
• /
• pp.368-371
• /
• 2005

In this paper, a small band pass filter is designed using new probe type for wireless communication system. In order to provide a band pass filter which can be reduced in dimension, can be reduced in height, and can be surface-mounted. The filter was fabricated using $TE_{01{\delta}}$ mode dielectric resonator. The input/output probes are attached to coner portion of the rectangular metal cavity. Results of the manufactured filter$(12{\times}12{\times}8mm)$ show that the center frequency is 9.953GHz, the insertion loss is -2.98 dB, the 3dB-bandwidth is 15 MHz, and the lode Q is 663.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.27 no.10
• /
• pp.50-58
• /
• 2013

In Wireless Sensor Network, clustering scheme is used to prolong the lifetime of WSN by efficient usage of energy of sensor. In the distributed clustering protocol just like LEACH, every sensor in a network plays a cluster head role once during each epoch. So the FND is prolonged. But, even though every sensor plays a head role, the energy consumed by each sensor is different because the energy consumed increases according to the distance to the Base Station by the way of multiple increase. In this paper, we propose a mechanism to select a head depending on the distance to Base Station, which extends the timing of FND occurrence by 68% compared to the LEACH and makes network stable.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.19 no.1
• /
• pp.182-189
• /
• 2005

In this paper, A web-based server system was developed based on PDA(Personal Digital Assistants) for controlling and managing light facilities on-line with wireless communication efficiently. The control box of current light facilities may be implemented based on simple operational function. The operational quality of the light facilities will be efficiently improved with some practical advantages such as reduction of required facility, manpower and time in managing the lights and control boxes by using the popular PDA.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.26 no.4
• /
• pp.1-5
• /
• 2012

By using LED optical devices and improving the efficiency of optical devices as well as lighting apparatus for humans, LED lighting industry puts the purpose of manufacturing the main products related with information, electric, large-sized LCD BLU, automobile, shipbuilding, agriculture, medical treatment, environment, and telecommunications, etc. Moreover, the main products and the industrial lighting products are manufactured with fusion, as the result, LED lighting industry provides various effects as well as sources of technology based on practical use of LED technology in order to develop the industry from the perspective of the lower price, the higher efficiency, the higher function, the deeper reliance. In the future, not only the development of new LED technology but also the fusion and combination of digital IT technologies using wire-wireless communication, sensor, controller, and artificial intelligence will be expected to create new industrial fields.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.11
• /
• pp.123-129
• /
• 2011

In terrestrial wireless optical communication links, atmospheric effects including turbulence, absorption and scattering have significant impact on the system performance. Based on the analysis of transmission in atmospheric channel concerning 830[nm] wavelength diode laser beam, performance of free space optical (FSO) link utilizing Galilean optics as a laser beam transmitting and receving optics, PIN photodiode as a detecting device. In this paper we designed optical link equation for received optical power and we analyze the atmospheric effects on the signal to noise ratio (SNR) and bit error rate (BER) of an terrestrial FSO system. We show that the possible communication distance for BER=$10^{-9}$ in proposed adverse atmospheric conditions.