• 수산해양교육연구
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• 제16권2호
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• pp.210-217
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• 2004

Cooling technology has been a vital prerequisite for the rapid, if not explosive, growth of the electronic equipment industry. This has been especially true during the last 20 years with the advent of intergrated circuit chips and their applications in computers and related electronic products. The purpose of this study is to develop a telecommunication equipment cooling system using a thermoelectric module combined with cooling fan. Thermoelectric module is a device that can perform cooling only by input of electric power. In the present study, the cooling package using the thermoeletric module has been developed to improve the thermal performance. The cooling characteristics of the electronic chip was placed into the subrack and it can be rapidly assembled or disassembled in the equipment rack. As a preliminary experiment, the cooling performances between a conventional way using a cooling fin and a proposed method applying the thermoelectric module was comosed and analyzyed. The cooling performance at a simulated electronic component packaging a thermomodule operated well.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 E
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• pp.1718-1720
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• 1997

This paper deals with n rise in electric potential of telecommunication line for electric power system by lightning surges. When $1.2/50{\mu}s$ and $8/20{\mu}s$ impulse voltage and current were applied on telecommunication cable, the voltage waveforms at the end terminal and equipment were measured. The telecommunication lines, which consist of 60 conductors and 3.5km in length, have some surge protectors such as preposition lightning arrester and TVSS. In each case, the rise in electric potential was measured for differential mode and common mode, respectively. Also, the rise in ground potential and the induced voltages were measured and analyzed. As a result, a significant rise in ground potential was observed for lightning surge. It can cause failure or malfunction of telecommunication systems.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2001년도 춘계학술대회
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• pp.67-75
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• 2001

Circuitry to be connected to a Telecommunication Network consists of SELV CIRCUITS or TNV CIRCUITS. So International Standards, like as ITU-T Recommendation K.11, UL 1950, CSA C22.2 950 have been taken to reduce the risk that the Overvoltages from the power lines and from electrictraction lines, that may be received from the telecommunication network. Legal requirements may exist regarding permission to connect equipment having PTC components to a telecommunication network. Surge suppressors that bridge the insulation shall have a minimum d.c. sparkover voltage of 1.6 times the rated voltage or 1.6 times the upper voltage of the tared voltage range of the equipment. If left in place during electric strength testing of insulation, they shall not be damaged. In this work, The Conception ＆ Fail-Mode Analysis of PTC components for Over-Current Protection is proposed. It guarantees the protection for PL Claim about this Subject.

• 전기학회논문지
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• 제63권11호
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• pp.1564-1570
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• 2014

An electric vehicle (EV) not only receives electric power from the electric vehicle supply equipment (EVSE), but it also exchanges the information regarding charging process with the power gird through the EVSE. However, the EV and EVSE communicate using the ISO/IEC 15118 standard while the EVSE and power grid communicate using the IEC 61850 standard. Therefore, the EVSE should support both the ISO/IEC 15118 and IEC 61850 standards, and provide a data mapping function between the two communication protocols so that the EV and power grid, which support different protocols, can communicate with each other throughout the charging process. In this paper, we propose a mapping method of the EVSE, which converts the ISO/IEC 15118 data to IEC 61850 and vice versa, based on the XML schema of each protocol. The proposed method converts the data using the XSL (eXtensible Stylesheet Language) method, which defines the data mapping between two XML schemas. Our approach is more flexible and easier to maintain against changes in charging scenarios and the standards than other existing approaches such as one-to-one data mapping methods.

• International Journal of Internet, Broadcasting and Communication
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• 제9권2호
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• pp.1-10
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• 2017

The high costs of electric vehicle supply equipment (EVSE) and installation are currently a stumbling block to the proliferation of electric vehicles (EVs). The cost-effective solutions are needed to support the expansion of charging infrastructure. In this paper, we develope EV charging system based on the big data analysis of the power consumption patterns. The developed EV charging system is consisted of the smart EV outlet, gateways, powergates, the big data management system, and mobile applications. The smart EV outlet is designed to low costs of equipment and installation by replacing the existing 220V outlet. We can connect the smart EV outlet to household appliances. Z-wave technology is used in the smart EV outlet to provide the EV power usage to users using Apps. The smart EV outlet provides 220V EV charging and therefore, we can restore vehicle driving range during overnight and work hours.

• 설비공학논문집
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• 제19권10호
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• pp.710-717
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• 2007

Electric and telecommunication industries are constantly striving towards miniaturization of electronic devices. Miniaturization of chips creates extra space on PCBs that can be populated with additional components, which decreases the heat transfer surface area and generates very high heat flux. Even though an air-cooling technology for telecommunication equipment has been developed in accordance with rapid growth in electrical industry, it is confronted with the limitation of cooling capacity due to the rapid increase of heat density. In this study, liquid-cooling heat exchangers with MPCM slurries were designed and tested by varying geometry and operating conditions. The liquid-cooling heat exchangers with 4-paths showed higher cooling performance than the others. The cooling performance of liquid cooling heat exchanger with MPCM slurries was more enhanced than that of the air cooling system. It's performance was also slightly superior to that of the water cooling system at the inlet temperature of $19^{\circ}C$.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1014-1019
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• 2011

The substation automation is a system to remote-monitor and control electric power flow. And in line with electrification of railway, an interest in electric railway substation automation is increasing. IEC standardized IEC 61850, IEC 61968 and IEC 61970 communication protocol for the telecommunication standardization of the electric power automation industry. The recent SCADA systems in managed electric railway substations are have the problem about the compatibility with the products which fit to the international standard specification afterward. In this paper, the model of electric railway substation automation based on IEC 61850 and IEC 61970 is presented. And the method supporting the compatibility between the equipment is proposed.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2005년도 하계학술대회
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• pp.141-145
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• 2005

In this paper, UWB system did research about effect that interference effect with neighborhood single equipment or nearby group equipment gets In DMB service. 2.6425GHz satellite digital multimedia broadcasting service(SDMB) that electric wave interference special quality is contiguity frequency-band including interference of signal by unnecessary radiation level that is radiated in UWB system, and 3.4125GHz broadcasting relay net that is In-band frequency-band and interference effect degree that get in service did comparative analysis. SDMB system was BER $1{\times}10^{-4}$ that interference effect happens from 6.5m point and broadcasting signal reception is possible at 4m point. Also, it was BER $1{\times}10^{-4}$ that interference effect begins to happen from 5.0m point about center frequency 3.4126GHz and broadcasting signal reception is possible at 2m point. And, confirmed that UWB system of impulse method is less interference effect about 2 dB than UWB system of OFDM method, to electric wave of UWB system that is small output

• 정보통신설비학회논문지
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• 제4권2호
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• pp.1-8
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• 2005

본 논문에서는 UWB 시스템이 근처의 단일 장비 또는 집단 장비와의 간섭영향이 DMB 서비스에 미치는 영향에 관한 연구를 하였다. 이를 위해 UWB 시스템에서 방사되는 불요 방사 레벨에 따른 신호의 간섭을 비롯한 전파 간섭 특성이 인접 대역인 2.6425GHz SDMB(Satellite Digital Multimedia Broadcasting)와, In-band 대역인 3.4125GHz 방송 중계망과 서비스에 미치는 간섭 영향의 정도를 비교 분석하였으며, 방송 중계망과 간섭 측정 장비의 변조방식은 Impulse 방식과 OFDM 방식을 사용하였다. SDMB 시스템에서 Impulse 방식은 2m 지점에서부터 간섭 영향이 발생하여 1.4m 지점에서 방송 신호 수신이 가능한 $BER=1{\times}10^4$ 이었으며, OFDM 방식은 0.8m 지점에서부터 간섭 영향을 받아 0.5m 지점에서 방송 신호 수신이 가능한 $BER=1{\times}10^4$ 이었다. 또한 Gap-Filler 중심 주파수에 대해서는 0.01m 이상 이격 시는 간섭영향이 없었다. 따라서 소출력인 UWB 시스템의 전파가 DMB 서비스에 간섭 영향 없이 시스템에 적용하기 위해서는 Impulse 방식의 UWB 시스템보다 OFDM 방식의 UWB 시스템이 간섭 영향이 적다는 것을 확인하였다.

• 정보통신설비학회논문지
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• 제7권1호
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• pp.23-31
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• 2007

본 논문에서는 UWB 시스템이 근처의 단일 장비 또는 집단 장비와의 간섭영향이 방송통신서비스에 미치는 영향에 관한 연구를 하였다. 이를 위해 UWB 시스템에서 방사되는 불요 방사 레벨에 따른 신호의 간섭을 비롯한 전파 간섭 특성이 인접 대역인 2.6425GHz SDMB(Satellite Digital Multimedia Broadcasting)와, In-band 대역인 3.4125GHz 방송 중계망과 서비스에 미치는 간섭영향의 정도를 비교 분석하였으며, 방송 중계망과 간섭측정 장비의 변조방식은 Impulse 방식과 OFDM 방식을 사용하였다. SDMB 시스템에서 Impulse 방식은 2m 지점에서부터 간섭 영향이 발생하여 1.4m 지점에서 방송 신호 수신이 가능한 $BER\;=\;1{\times}\;10^{-4}$ 이었으며, OFDM 방식은 0.8m 지점에서부터 간섭 영향을 받아 0.5m 지점에서 방송 신호 수신이 가능한 $BER\;=\;1{\times}\;10^{-4}$ 이었다. 또한 Gap-Filler 중심 주파수에 대해서는 0.01m 이상 이격 시는 간섭영향이 없었다. 따라서 소출력인 UWB 시스템의 전파가 방송통신서비스에 간섭 영향 없이 시스템에 적용하기 위해서는 Impulse 방식의 UWB 시스템보다 OFDM 방식의 UWB 시스템이 간섭 영향이 적다는 것을 확인하였다.