• 한국정보통신설비학회:학술대회논문집
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• 2009.08a
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• pp.49-53
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• 2009

If you are installing communications cables in the pipeline based on the kind of cable installation tension within the allowed range of the tension must be maintained. The tension of the installation affected by the cable types, cable jacketed status, cross-sectional shape of the pipeline, the substance present in the pipeline, pipeline linear, the direction of the cable is installed. Depending on the size of the cable installation tension fatal influence on the quality of communication, or, at worst, the cable can be cut. In this paper, test bed for building a pipeline and using optical cable and such cable tension was measured. Freedom of access to the pipeline used in the experiment, and installed in conjunction with the cable tension was measured. It possible for the cable installation to determine whether a duplicate, and have compared the actual measured tension value and the theoretical expression.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.573-576
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• 2012

We have analyzed the induction effects by separation distance between the power feeding station and the telecommunication cables. To do this we measured the induced voltage in 11 sections(10km) between Jangseong and Imgok at Jeon-nam province using telecommunication cable installed nearby KTX's feeder line. Sub-section has about 1km length of telecommunication cable. And we used normalization method in installed length of telecommunication cables and mutual inductance to analysis the induction effects more rationally.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.4
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• pp.517-522
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• 2013

The spurious electromagnetic radiation is generated due to the RF unbalanced current on a conductive cable connecting an electronic device to another. A metamaterial-based filtering geometry with frequency selectivity is suggested to reduce the radiation with a bandgap structure, where the right-handed inductance and capacitance stem from the transmission-like configuration between the cable and the metal protrusion, and the left-handed components come from the narrow cavities. The effect of the structure on the unbalanced current pulse and its spurious radiation is presented in the FDTD-method frame work.

• 한국정보통신설비학회:학술대회논문집
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• 2003.11a
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• pp.203-227
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• 2003

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.293-295
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• 2007

OSP 에서 주로 사용되는 Drop Cable 은 통신단말인 단자함에서 통신전주 두상에 설치된 인입클램프 걸이에 인입클램프를 취부하고, 가공구간을 통해 가입자 댁으로 가설을 하며, 가입자 댁의 일정한 지점에 인입벽철 또는 인입용 훅을 설치하고, 인입클램프를 체결하여 Drop Cable 의 이도 및 루트를 고려하여 개통공사를 완성하여 해당서비스를 공급하게 된다. 이때, 사용되는 Drop Cable 은 일반적으로 자기지지를 할 수 있는 "8" 형태의 자기지지형 Drop Cable 을 주로 이용하였으나, 광섬유를 이용하는 FTTH 사업에서는 서비스 개통시 "0" 형태의 Optical Drop Cable(광옥외선)을 사용하여 개통작업의 시공성 및 생산성을 향상 시켰다. 이에 사용되는 적합한 인입광 클램프는 광옥외선의 외형적인 구조에 손상을 전가하여서는 안되며, 광옥외선 내부의 광섬유에 손상을 가하지 않는 최소의 손실을 가지며, 일정한 인장력을 유지하고 있어야 한다. 따라서, 위의 사항을 고려한 인입 광클램프의 특성에 대해 고찰하고자 한다.

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.331-335
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• 2007

방송과 초고속인터넷 서비스를 동시에 제공할 수 있는 HFC(Hybrid Fiber Coaxial) 망은 상/하향이 비대칭 구조이며, 하향속도에 비해 상향속도가 1/10 수준이어서 상향 트래픽이 과다하게 생성될 경우 인터넷속도 지연이 발생한다. 지연에 민감한 VoIP 서비스의 품질보장 방안으로는, DOCSIS(Data Over Cable System Interface Specification) 1.1 기반의 상향 스케쥴링 기능을 이 용한 VoCM(Voice Over Cable Modem)이 있다. 그러나 별도의 VoCM을 사용해야 하며 아날로그 전화기를 사용해 IP 기반의 VoIP 단말을 사용할 수 없다는 단점이 있다. 일반 CM(Cable Modem)에 DOCSIS 1.1 Config File을 이용하여 VoIP 품질을 보장할 경우 별도의 트래픽 대역을 항상 점유해야 하는 단점이 있다. 이에, 본 논문에서는 효율적 대역폭 이용과 단말장비에 종속적이지 않은 방안을 제안하고 일반 CM을 통한 유무선 환경하에서 Dynamic QoS(Quality Of Service)를 제공할 수 있는 PCMM(Packet Cable MultiMedia) 적용 방안 및 시험결과에 대해 고찰하고자 한다.

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.285-288
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• 2007

This article presents the change characteristics of induced noise whether the sheath layer of the cable is grounded or not. As what affects the induced noise, there are power influence or longitudinal transverse voltages and its weighted filtered voltage. The sheath ground is basicaly predicted to have the effects of alleviation on the power influence. But practically the effects may not happen in the case of common cable's sheath layer. Rather there are cases that the ground of sheath affects so that the noise level could increase. So we need to scrutinize the effects of the sheath gorund in the measures for the protection against electromagnetic induction by powerline or traction line system. And the evaluation of using the designated shielding purpose cable is needed.

• Journal of Advanced Navigation Technology
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• v.11 no.1
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• pp.43-49
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• 2007

In this paper, the performance of OFDM/64QAM systems under Rummler model based cable channel is evaluated through computer simulation, and then the degree of performance improvement is estimated when adopting adaptive LMS equalizer. From the performance evaluation results, in the Rummler two-ray channel model, it is known that the performance improvement degree by adopting equalizer is greatly increased in case of attenuation coefficient of reflected ray (b) being less than 0.15, but when attenuation coeffcient (b) is larger than 0.15, the performance improvement degree by adopting equalizer shows little changes in almost all range of Eb/No.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.621-624
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• 2001

A metal sheath provides a cable with electrostatic screening and a degree of magnetic screening. The presence of a screen on a cable also reduces the induction arising from the high-frequency components of transients caused by power-line switching and also induced transients from lightning strokes; such transient induced voltages are of increasing importance with the increasing use of miniaturized telecommunication equipment with very small thermal capacity. This paper describes electrostatic induction and electromagnetic induction caused by power interference. Also screening factors are proposed.

• Proceedings of the KIEE Conference
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• 1997.07e
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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.