• Title/Summary/Keyword: Signal reduction

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Vehicle Collision Avoidance Sensor with Interference Immunity to Own Transmitted Signal (자차 송신기 신호 간섭회피 기능을 갖는 차량의 충돌방지 센서)

  • Choi, Kyoo-Nam
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.3
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    • pp.433-438
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    • 2013
  • Interference reduction method of vehicle collision avoidance sensor which is used for the low speed electric vehicle has been investigated. Various methods were attempted for the vehicle collision avoidance distance sensor, which received a transmitted signal from a front driving vehicle to measure the distance between two vehicles, to avoid interference by the own transmitter signal toward the rear following vehicle. In this study, -12dB of interference cancellation ratio was realized by using the phase cancellation method to the transmitted signal from the own vehicle. Proposed phase cancellation method is regarded to have the advantage of continuous monitoring in comparison to the conventional time sharing transmitting and receiving method.

Design of 250-Mb/s Low-Power Fiber Optic Transmitter and Receiver ICs for POF Applications

  • Park, Kang-Yeob;Oh, Won-Seok;Choi, Jong-Chan;Choi, Woo-Young
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.11 no.3
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    • pp.221-228
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    • 2011
  • This paper describes 250-Mb/s fiber optic transmitter and receiver ICs for plastic optical fiber applications using a$ 0.18-{\mu}m$ CMOS technology. Simple signal and light detection schemes are introduced for power reduction in sleep mode. The transmitter converts non-return-to-zero digital data into 650-nm visible-red light signal and the receiver recovers the digital data from the incident light signal through up to 50-m plastic optical fiber. The transmitter and receiver ICs occupy only 0.62 $mm^2$ of area including electrostatic discharge protection diodes and bonding pads. The transmitter IC consumes 23 mA with 20 mA of LED driving currents, and the receiver IC consumes 16 mA with 4 mA of output driving currents at 250 Mb/s of data rate from a 3.3-V supply in active mode. In sleep mode, the transmitter and receiver ICs consume only 25 ${\mu}A$ and 40 ${\mu}A$, respectively.

A Study on Modified IGC Algorithm for Realtime Noise Reduction (실시간 소음 제거에 적합한 변형 IGC 알고리즘에 관한 연구)

  • Lee, Chae-Wook
    • Journal of the Institute of Convergence Signal Processing
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    • v.14 no.2
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    • pp.95-98
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    • 2013
  • The LMS(Least Mean Square) algorithm, one of the most famous, is generally used because of tenacity and high mating spots and simplicity of realization, But it has trade-off between nonuniform collection and EMSE(Excess mean square error). To overcome this weakness, a variable step size is used widely, but it needs a lot of calculation loads. In this paper, we suggest changed algorithm in case of environment changes of cars and reduce amount of calculation as it uses original signal and noise signal of IGC(Instantaneous Gain Control) algorithm. In this paper, logarithmic function is removed because of real-time processing IGC. The performance of proposed algorithm is tested to adaptive noise canceller in automobile.

A convergence analysis of Block MADF algorithm for adaptive noise reduction

  • Min, Seung-gi;Young Huh;Yoon, Dal-hwan
    • Proceedings of the IEEK Conference
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    • 2002.07a
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    • pp.377-380
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    • 2002
  • When it calculates the optimum price of filter coefficient, the many operation quantity is necessary. Is like that the real-time control is difficult and the hardware embodiment expense is big. The case which does not know advance information of input signal or the case where the statistical nature changes with change of surroundings environment is necessary the adaptive filter. Every hour to change a coefficient automatically and system in order to reach to the condition of optimum oneself, the fact that is the adaptive filter. When it does not the quality of input signal or it does not know the environment of surroundings every hour changing, it does not emit not to be, in order to collect, the fact that is the adaptive filter. The case of the Acoustic Echo Canceler does thousands filter coefficients in necessity. It reduces a many calculation quantity to respect, it uses the IIR filter from hour territory. Also it uses the block adaptive filter which has a block input signal and a block output signal. The former there is a weak point where the stability discrimination is always demanded. Consequently, The block adaptive filter is researched plentifully. This dissertation planned the block MADF adaptive filter used to MADf algorithm.

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Identification of an antimicrobial peptide from human methionine sulfoxide reductase B3

  • Kim, Yong-Joon;Kwak, Geun-Hee;Lee, Chu-Hee;Kim, Hwa-Young
    • BMB Reports
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    • v.44 no.10
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    • pp.669-673
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    • 2011
  • Human methionine sulfoxide reductase B3A (hMsrB3A) is an endoplasmic reticulum (ER) reductase that catalyzes the stereospecific reduction of methionine-R-sulfoxide to methionine in proteins. In this work, we identified an antimicrobial peptide from hMsrB3A protein. The N-terminal ER-targeting signal peptide (amino acids 1-31) conferred an antimicrobial effect in Escherichia coli cells. Sequence and structural analyses showed that the overall positively charged ER signal peptide had an Argand Pro-rich region and a potential hydrophobic ${\alpha}$-helical segment that contains 4 cysteine residues. The potential ${\alpha}$-helical region was essential for the antimicrobial activity within E. coli cells. A synthetic peptide, comprised of 2-26 amino acids of the signal peptide, was effective at killing Gram-negative E. coli, Klebsiella pneumoniae, and Salmonella paratyphi, but had no bactericidal activity against Gram-positive Staphylococcus aureus.

A Study on Noise Reduction Characteristics of Active Noise Controller Using Hysteresis Control Method (히스테리시스 제어 방식을 이용한 능동 소음 제어기의 소음저감 특성에 관한 연구)

  • 이승요;김홍성;최규하
    • The Transactions of the Korean Institute of Power Electronics
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    • v.2 no.2
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    • pp.35-40
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    • 1997
  • The hysteresis control method has been frequently used for current control of power conversion equipments or motor drive systems. This method makes the measured signal follow the reference signal by changing the control signal whenever the error signal exceeds the preset band width. In this paper, hysteresis control method with fast response characteristics is applied for active noise control to suppress acoustic noise. Both Pentium processor and sound blaster 16 are used for experimental implementation, which executes A/D, D/A conversion and also is used as operating source of loudspeaker for audible noise cancellation.

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A Small Signal Modeling of Three-level Neutral-Point-Clamped Inverter and Neutral-Point Voltage Oscillation Reduction (3레벨 NPC인버터의 소신호 모델링과 중성점 전압 진동 저감)

  • Cho, Ja-Hwi;Ku, Nam-Joon;Joung, Seok-Eon;Hyun, Dong-Seok
    • The Transactions of the Korean Institute of Power Electronics
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    • v.19 no.5
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    • pp.407-414
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    • 2014
  • This study proposes a control design for the grid output current and for reducing the neutral-point voltage oscillation through the small-signal modeling of the three-phase grid connected with a three-level neutral-point-clamped (NPC) inverter with LCL filter. The three-level NPC inverter presents an inherent problem: the neutral-point voltage fluctuation caused by the neutral-point current flowing in or out from the neutral point. The small signal modeling consists of averaging, dq0 transformation, perturbing, and linearizing steps performed on a three-phase grid connected to a three-level NPC inverter with LCL filter. The proposed method controls both the grid output and neutral-point currents at every switching period and reduces the neutral-point voltage oscillation. The validity of the proposed method is verified through simulation and experiment.

Communication-Power Overhead Reduction Method Using Template-Based Linear Approximation in Lightweight ECG Measurement Embedded Device (경량화된 심전도 측정 임베디드 장비에서 템플릿 기반 직선근사화를 이용한 통신오버헤드 감소 기법)

  • Lee, Seungmin;Park, Kil-Houm;Park, Daejin
    • IEMEK Journal of Embedded Systems and Applications
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    • v.15 no.5
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    • pp.205-214
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    • 2020
  • With the recent development of hardware and software technology, interest in the development of wearable devices is increasing. In particular, wearable devices require algorithms suitable for low-power and low-capacity embedded devices. Among them, there is an increasing demand for a signal compression algorithm that reduces communication overhead, in order to increase the efficiency of storage and transmission of electrocardiogram (ECG) signals requiring long-time measurement. Because normal beats occupy most of the signal with similar shapes, a high rate of signal compression is possible if normal beats are represented by a template. In this paper, we propose an algorithm for determining the normal beat template using the template cluster and Pearson similarity. Also, the template is expressed effectively as a few vertices through linear approximation algorithm. In experiment of Datum 234 of MIT-BIH arrhythmia database (MIT-BIH ADB) provided by Physionet, a compression ratio was 33.44:1, and an average distribution of root mean square error (RMSE) was 1.55%.

Magnetic resonance imaging findings of the retrodiskal tissue in TMJ internal derangement (측두하악관절 내장증에서의 관절원판 후조직의 자기공명영상)

  • Cho Bong-Rae
    • Imaging Science in Dentistry
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    • v.33 no.2
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    • pp.63-70
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    • 2003
  • Purpose: To describe the MRI findings of the retrodiskal tissue in patients presenting with TMJ internal derangement and to correlate these findings with clinical and other MRI manifestations. Materials and Methods: One hundred eighteen joints of 63 patients with TMJ internal derangement were examined by MRI. Tl-weighted sagittal MR images taken in both closed- and open-mouth were evaluated for the presence of demarcation between disk and retrodiskal tissue, the presence of low signal intensity, and the depiction of the temporal part of the posterior attachment. The results were correlated with the duration of TMJ internal derangement, the presence of pain, and other MRI findings, including the type of internal derangement, the extent of disk displacement, the degree of disc deformation, and the presence of osteoarthrosis. Results: A significant relationship between the presence of low signal intensity in the retrodiskal tissue and other MRI findings was determined. Low signal intensity on the open-mouth view was observed more frequently in patients with disc displacement without reduction, severe disc displacement and deformation, and osteoarthrosis (p<0.05). The demarcation between disk and retrodiskal tissue, and the depiction of the temporal part of the posterior attachment(TPA) were correlated neither with clinical, nor with other MRI findings. Conclusion: This study suggests that low signal intensity in the retrodiskal tissue on open-mouth MR image can be indicative of advanced stages of disk displacement.

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Noise Shaping effects of Signal-blurred DPCM (신호 몽롱화 예측부호화의 잡음 천이 특성)

  • 황재정;이문호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.10
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    • pp.964-971
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    • 1991
  • In DPCM coder which has flat notse distributions, reconstruction noises might be shaped or transferred to hign frequency portion using the relevant noise reduction loop under the constraints of image compression. Noise shaping filter directly in loop can be used, but we shows the complete characteristics of signal blurred DPCM coder in view of data compression and noise processing. Equi weighting in bluming procedure of prefilter is introduced and the blurred signal is restored by debiurning postfilter. Noise shaping tegion on two dimensional frequency domain depends upon the size of masking filter. In spite of its noise increments by the signal blurring, the algonthm is effective for the visually relevant coding which has low pass freqency properties.

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