• Journal of the Korean Institute of Gas
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• v.12 no.4
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• pp.8-13
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• 2008

The stray current interference problem could induce the corrosion of near-by structure and rail itself. Many efforts has been concentrated on the reduction of the interference. In this work the influences of separation distance, soil resistivity, pipe coating resistance, leak resistance of rail were studied using the numerical analysis methods. These analysis could be used to estimate the sensitivity of each variables in the study of the mitigation method and their numerical analysis.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.2
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• pp.19-24
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• 2010

This paper analyzes potential interference effect of DTV service on Radio Microphone in adjacent channel. For analysis, we assume that DTV operates on CH 51(692 MHz ~ 698 MHz) and radio microphone operates on CH 52 (698 MHz ~ 704 MHz) according to the Korea Communications Commission policy. Minimum Coupling Loss(MCL) method is used to determine the required protection distance and Monte Carlo method is used to determine guard band to meet interference probability of 0 % below. In conclusions, protection distance of 1.71 km and guard band of 2.4 MHz are required for indoor and protection distance of 18.86 km and guard band of 5.7 MHz are required for outdoor.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.2
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• pp.69-75
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• 2010

In this paper, we analyze an effect co-existence between digital television (DTV) and 802.22 wireless regional area network (WRAN) systems. We set DTV as an interfering system and 802.22 WRAN as a victim system. When they share the same spectrum, we calculate the minimum separation distance. In analysis, we compare a minimum coupling loss (MCL) with a transmission loss (TL) for determining whether there exists the potential interference or not. The minimum separation distance is determined when the TL is larger than the MCL. In this case, the DTV system does not affect any harmful effect to 802.22 WRAN.

• Journal of the korean Society of Automotive Engineers
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• v.2 no.1
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• pp.5-8
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• 1980

스트레인 게이지를 사용하여 회전체의 스트레인을 측정할 경우, 회전체 내에 브리지를 구성하여 브리지의 4점의 입출력단을 슬립 링을 매개로 정지 쪽으로 끌어내어 측정하는 것이 일반적으로 상용되고 있는 방법이다. 이 방법에 의하면 1측정점에 대하여 4소자의 슬립 링을 필요로 하기 때문에 다수점의 스트레인 측정은 곤란하다. 그래서 브리지를 셰브론 브리지식으로 구성하면 슬립링수를 대폭 줄일 수 있다. 그러나 이 방법은 다음의 이유로 인하여 측정 정밀도가 저하하는 결점이 있다. (1) 종래의 동응력 측정기는 입력 임피이던스가 작기 때문에 각 채널간에서 간섭을 일으킨다. (2) 채널간의 간섭은 공통브리지 저항값의 크기에 따라서도 영향을 받는다. 이 저항값이 작을수록 간섭량은 감소되기 때문에 이것을 작게 하면 브리지의 합성저항이 작아 지고, 브리지전원공급용 슬립 링의 접촉저항의 영향이 커진다. 그래서 셰브론 브리지식으로 슬립 링을 감소시키는 동시에 위에 말한 결점을 없앤 새로운 다점응력 측정기를 개발했다. 이 스트 레인측정기는 종래의 동스트레인 측정기와 다른 중요한 점은 다음의 두가지이다. (1) 증폭기의 입력임피이던스(impedance)를 크게 (약 50k.ohm.)하는 동시에 공통브리지의 저항을 작게 (약 10.ohm.)하고, 각 채널간의 간섭을 없앴다. (2) 브리지전원공급용 슬립 링의 접촉저항에는 관계없이 브리지에는 항상 일정한 전압이 공급 되게 했다. 본 보고에서는 (1)에 대한 검토는 생략하고, 주로 (2)에 대하여 기술한다.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.4
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• pp.54-60
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• 2001

In this thesis, We analyze performance evaluation of one channel B-WLL IF receiver system. Among the item of receiver performance, inter-modulation interference and yield analysis is especially focused. Since inter-modulation interference cause bad influence on system performance due to unwanted third order harmonic located in desired frequency band, third order harmonic causing inter-modulation interference should be efficiently removed. Yield analysis is observing influence on system performance when system element parameter is statistically varied, and in this thesis, system output is observed for LNA parameters. Additionally, Scheme for LNA gain adjustment to reduce inter-modulation interference is proposed by observing variation of third order harmonic output for LNA gain variation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.4
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• pp.901-913
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• 1998

This paper presents a new analytical approach for the evaluation of the reverse link interference in a CDMA cellular system with unequal cell loading. In particular, the dynamic nature of the reverse link power control has been taken into account in the proposed approach so that a realistic effect of unequal cell loading, including the shadowing and soft handoff, on system capacity may be precisely captured. This is aspect that has not beensuccessfully formmulated and rarely attempted tosolve in any previous analytical approach. Our computational result shows that as the loading of every tier of surrounding cells is doubled, the subscriber capacity of the reference cell can be reduced as much as 27% of that obtained in the case that the effect of power control is not appropriately modeled.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.189-194
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• 2012

This paper is about frequency allocation of LTE Base Station(BS) in the spare band which is generated by DTV transition. In the case of frequency allocation of LTE BS in adjacent band with DTV channel 51 among the spare band, the guard bands that requires for no interference between LTE and DTV system were calculated. As a result, 5.5 MHz of guard band for LTE BS and 2 MHz of guard band for DTV receiver were suggested based on interference analysis between LTE BS and DTV BS, respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.10 no.3
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• pp.135-146
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• 1985

The error rate equation of MSK(Minimum Shift Keying) signal transmitted through the fading channel has been derived in the interference and impulsive noise environments. The error rate performance of MSK system have been evaluated and shown in figures as parameters of carrier-to-noise power ratio(CNR), carrier-to-interferer power ratio(CIR), impulsive index, the ratio of Gaussian noise power component to impulsive noise power component, and fading figure. The results show that, in the fading environment, the error is occurred more frequently by Gaussian noise in the deep fading, however in the shallow fading, impulsive noise is more dominant than Gaussian noise. And in thepresence of interference and fading, interferer deteriorates the MSK receiving system severely even if the interferer is weak.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.701-704
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• 2005

In this paper, we looked into the feature of a transmission system of the terrestrial digital broadcasting system and considered a ATSC 8-VSB transmission standard. Also, we analyzed the performance with the influence of an interchannel interference by the ATSC standard. As a result, the case not to consider Rician fading, The influence of the interfere did not exist if Frequency interval fell off over the 20MHz. The case to consider Rician fading, the system had the degradation of the performance.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.4
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• pp.128-135
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• 1998

In the high speed range for salient type synchronous reluctance motor, the effect of iron loss can not be negligible. In this paper, under he assumption that stator iron loss is generated from the equivalent eddy current in the stator, we derive the voltage equations including iron loss from the model that is added the equivalent iron loss in the equivalent inductance in series. The variation of iron loss is dependent on the increase of the operating frequency change for he worse a performance of the vector control system. As there is cross coupling between the d and q axes, it is hard to apply the vector control to the proposed model. Hence, we propose a decoupling current controller for including the effects of iron loss, And we show that the proposed vector control scheme achieves the desired performances through simulation results.