• Title/Summary/Keyword: timing recovery

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Research on the Difference in the influences upon consumers' Response Recoveries of Reward Method in the dissatisfaction Situation - Focusing on the Moderating Effects of Reward Timing and Reward Intensity - (불만족 상황에서의 보상방식이 소비자의 반응회복에 미치는 영향의 차이에 관한 연구 - 보상시기와 보상강도의 조절효과를 중심으로 -)

  • Kim, Sook-Hee;Kim, Yong-Ho
    • Management & Information Systems Review
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    • v.33 no.2
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    • pp.225-239
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    • 2014
  • An effect of reward program related to promotional activity has the limitation of being concentrated on a short-term performance or of inducing temporary re-purchase. Accordingly, this study verified the influence of reward method upon consumers' response recovery centering on interactive effects of reward timing and reward intensity, in order to expand a research of dissatisfaction situation. As for the objective of this study, first, the aim is to verify the difference in the influence of economic, non-economic, and combined rewards, which are reward methods of dissatisfaction situation, upon consumers' cognitive response recovery and emotional response recovery. Second, the aim is to confirm a moderating role of reward timing and reward intensity in the effect of consumers' response recovery according to reward methods. To design a research, the perfect factor design between subjects in 3X2X2 was used. As a result of major research, first, there was a difference in the influence upon consumers' response recovery depending on reward methods. Second, the influence of reward method upon consumers' response recovery had a difference depending on reward timing. Third, the influence of reward method upon consumers' response recovery had a difference depending on reward intensity. Consumers' response recovery level was confirmed to have the greatest influence in the combined reward. This study has a significance in newly applying the reward timing, in the dissatisfaction situation which is addressed in the general reward program. Through this study, the aim was to support the empirically analytical results of prior researches and to expand its role in several angles.

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The Optimization of Timing Recovery Loop for an MQASK All Digital Receivers (MQASK 디지털 수신기 타이밍 복원 루프 구조의 최적화 연구)

  • Seo, Kwang-Nam;Kim, Chong-Hoon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.1C
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    • pp.40-44
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    • 2010
  • The timing error detector(TED) employed in the closed loop type timing synchronization scheme for an MQASK all digital receiver suffers from the selfnoise-induced timing jitter. To eliminate the timing jitter a prefilter can be added in front of the TED. The prefilter method, however, degrades the stability and timing acquisition performance due to the loop delay and increases the complexity of the synchronizer. This paper proposes a polyphase filter type resampler approach to optimize the performance and architecture of the synchronizer simultaneously. The proposed scheme uses two resamplers which performs matched filtering and matched prefiltering so that the loop delay is minimized with minimal hardware resources. Simulation results showed an excellent acquisition performance with reduced timing jitter.

Effects of disturbance timing on community recovery in an intertidal habitat of a Korean rocky shore

  • Kim, Hyun Hee;Ko, Young Wook;Yang, Kwon Mo;Sung, Gunhee;Kim, Jeong Ha
    • ALGAE
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    • v.32 no.4
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    • pp.325-336
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    • 2017
  • Intertidal community recovery and resilience were investigated with quantitative and qualitative perspectives as a function of disturbance timing. The study was conducted in a lower intertidal rock bed of the southern coast of South Korea. Six replicates of artificial disturbance of a $50cm{\times}50cm$ area were made by clearing all visible organisms on the rocky substrate in four seasons. Each of the seasonally cleared plots was monitored until the percent cover data reached the control plot level. There was a significant difference among disturbance timing during the recovery process in terms of speed and community components. After disturbances occurred, Ulva pertusa selectively preoccupied empty spaces quickly (in 2-4 months) and strongly (50-90%) in all plots except for the summer plots where non-Ulva species dominated throughout the recovery period. U. pertusa acted as a very important biological variable that determined the quantitative and qualitative recovery capability of a community. The qualitative recovery of communities was rapid in summer plots where U. pertusa did not recruit and the community recovery rate was the lowest in winter plots where U. pertusa was highly recruited with a long duration of distribution. In this study, U. pertusa was a pioneer species while being a dominant species and acted as a clearly negative element in the process of qualitative recovery after disturbance. However, the negative effect of U. pertusa did not occur in summer plots, indicating that disturbance timing should be considered as a parameter in understanding intertidal community resilience in temperate regions with four distinct seasons.

Design of burst receiver with symbol timing and carrier synchronization (심벌동기와 반송파동기를 가진 버스트 수신기의 설계)

  • 남옥우
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2001.11a
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    • pp.44-48
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    • 2001
  • In this paper we describe the design of symbol timing and carrier synchronization algorithms for burst receiver. The demodulator consists of digital down converter, matched filter and synchronization circuits. For symbol timing recovery we use modified Gardner algorithm. And we use decision directed method for carrier phase recovery. For the sake of performance analysis, we compare simulation results with the board implemented by FPGA which is APEX20KE series chip for Alter. The performance results show it works quite well up to the condition that a frequency offset equal to 0.1% of symbol rate.

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A New Carrier Phase-Independent Discrete STR Algorithm for Sampled Receiver (샘플수신기를 위한 반송파위상에 독립적인 이산 STR 알고리듬)

  • 김의묵;조병록;최형진
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.4
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    • pp.561-571
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    • 1993
  • In this paper, a new discrete Symbol Timing Recovery (STR) algorithm, is proposed. This algorithm is derived from the optimum estimation theory. The algorithm combines the advantages of Mueller and $M\"{u}ller$ algorithm and Gardner algorithm, and avoids some of their shortcomings. The implementation of the new timing detector is simple and the combined operations of Carrier Recovery (CR) -STR is possible because the operation of the new STR is independent of the carrier phase. On the other hand, the behavior of nonlinear characteristics in the new algorithm is analyzed and explained. The performance evaluation is accomplished in detail by numerical calculations and Monte-Carlo simulations. In these respects, this algorithm is similar to Gardner's algorithm, but in tracking performance due to pattern jitter at small rolloff, the proposed algorithm is superior to Gardner's algorithm.

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Burst Mode Symbol Timing Recovery for VDL Mode-2 (VDL Mode-2에 적용 가능한 버스트 모드 심벌 타이밍 복원기)

  • Gim, Jong-Man;Choi, Seung-Duk;Eun, Chang-Soo
    • Journal of Advanced Navigation Technology
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    • v.13 no.3
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    • pp.337-343
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    • 2009
  • In this paper, we proposed a burst mode symbol timing recovery unit that is applicable to the VDL Mode-2 using D8PSK modulation. A method that IIR loop filter is used to minimize symbol timing error is hard to apply to burst mode because its convergence time is long. That is, the fast convergence property is important. In this paper, the proposed method takes one sample which has maximum symbol power after the initial synchronization has been achieved by using preambles. The main principle of operation is that the unit moves one sample clock to advance or retard according to symbol power. We verify that the proposed method is operated well in ${\pm}100$ ppm or greater through the test results between Australia ADS Corp. transmitter and the designed receiver.

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Performance Evaluation of Symbol Timing Recovery Algorithm for S-DMT Cable Modern (S-DMT 케이블 모뎀을 위한 심볼 타이밍 복원 알고리즘 성능평가)

  • Cho Byung-Hak
    • Journal of Digital Contents Society
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    • v.6 no.1
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    • pp.41-48
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    • 2005
  • In this paper, we propose and evaluate symbol timing recovery algorithm for S-DMT cable modern, which supports more channels and better quality symmetric mutimedia service over HFC network. We adopt timing recovery algorithm of PN sequence insertion in time domain and evaluate the performance of it in various noise channel such as AWGN, ISI, impulse. We verified that performance of this algorithm is depends on the channel noise environment and sampling clock offset and that over 10 dB degradation of Eb/No is occurred at the timing failure probability of $10^3$ in the composite noise channel of AWGN, ISI, and impulse in comparison with impulse noise-alone channel. finally, we verified that this algorithm showed good timing failure probability in case of sampling clock optimization was performed in advance.

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A Schedulability analysis and Recovery Technique of Real-Time System using TCPN (TCPN을 이용한 실시간 시스템의 스케쥴가능성 분석 및 회복기법)

  • Kim, Chun-Bae;Park, Heung-Bok
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.10
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    • pp.2797-2808
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    • 1999
  • Timing Constraint Petri Nets(TCPN) extend petri nets by adding timing constraints, it is provide a formal method for the modeling and analysis of real-time system. A real-time schedulability analysis decide that a set of concurrent processes will always meet its deadline. In this paper, we present TCPN model for real-time system include timing constraints and propose a schedulability analysis algorithm using them. Also, When the TCPN model is unscheduleable under the imposed timing constraints, we propose a recovery technique that will be scheduleable by the system specification modifying or timing constraints relaxing in the optimized time.

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An Alternative Carrier Phase Independent Symbol Timing Offset Estimation Methods for VSB Receivers (VSB 수신기를 위한 반송파 위상 오차에 독립적인 심벌 타이밍 옵셋 추정 알고리즘에 대한 연구)

  • Shin, Sung-Soo;Kim, Joon-Tae
    • Journal of Broadcast Engineering
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    • v.16 no.1
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    • pp.85-95
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    • 2011
  • In this paper, we propose an alternative carrier phase independent timing recovery method for VSB receivers. The Gardner algorithm may not estimate a timing offset in VSB systems when the residual carrier phase offset is contained in the signal. We use the conjugate multiplication of received signals for cancelling out the carrier phase offset. Then Gardner algorithm is employed for extracting the spectral line. The proposed method generates a consistent timing error even in the presence of the carrier phase offset.

The Low-Area of New arc-tangent Look-up Table and A Low-Overhead for CATV Modem Systems

  • Ban, Young-Hoon;Park, Jong-Woo;Cho, Byung-Lok;Song, Jai-Chul
    • Proceedings of the IEEK Conference
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    • 1999.06a
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    • pp.857-860
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    • 1999
  • It is made possible a removal of the preamble for carrier recovery and symbol-timing recovery by storing a burst in memory with low overhead QPSK demodulation and this demodulation method also effects frame efficiency improved by processed synchronization performance. In this paper, we have proposed that new algorithm for arc-tangent look-up table which transform the input I, Q data by phase. This I, Q data plays an important role in demodulation and makes demodulator with low-overhead by storing a burst in memory. To evaluate proposed new algorithm and symbol-timing recovery method, function simulation and timing verification have been done by using synopsys VHDL tool.

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