• Title/Summary/Keyword: phase matching

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A Study on The Method of Real-Time Arrythmia monitoring Using Modified Chain Coding (Modified Chain Coding 을 이용한 실시간 부정맥 모니터링 기법에 관한 연구)

  • Yun, Ji-Young;Lee, Jeong-Whan;Lee, Myoung-Ho
    • Proceedings of the KOSOMBE Conference
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    • v.1996 no.05
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    • pp.31-35
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    • 1996
  • This paper presents a real time algorithm for monitoring of the arrythmia of ECG signal. A real time monitoring, following by detecting a QRS complex, is the most important. Using 2-dimensional time-delay coordinates which are reconstructed by the phase portrait plotting special trajectory, we detect QRS complexes. In this study, arrythmias are detected by matching the past standard template with tile present pattern when changing abruptly In order to matching with each other, we propose modified chain coding algorithm which applies vetor table consisting of eight orthonormal code(=binary code) to the phase portraits. This algorithm using logical function increases the weight if exceeding to the threshold determinded by correlation value and the distance from a straight line(y=x). Evaluating the performance of the proposed algorithm, we use standard MIT/BIH database. The results are fellowing, 1) Improve the speed of matching template than that of cross-correlation ever has been used. 2) Because the proposed algorithm is robust to varing fiducial point, it is possible to monitor the ECG signal with irregular RR interval. 3) In spite of baseline wandering owing to the low frequency noise, monitoring performance is not reduced.

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The Objective Image Analysis for HCC and HH with a Axial Image of Liver CT Scan (Liver CT 단면영상에서 간세포암과 간혈관종의 객관적 영상분석)

  • Hwang, In-Gil;Ko, Seong-Jin;Choi, Seok-Yoon
    • The Journal of the Korea Contents Association
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    • v.15 no.9
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    • pp.411-417
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    • 2015
  • To distinguish between HCC and HH is one of the important test methods in determining the treatment method by determining the treatment method by distinguishing malignant growth and benign tumors in liver CT scan. Currently, the specialist is reading CT images by their subjective judgment. So, the purpose of this study is to treat reading the CT images even more objective way. The test times after injection contrast medium in this study are the before injection phase(Pre.), artery phase(35sec), portal phase(70sec) and delay phase(180sec). The general pattern change of HCC in change of contrast enhancement pattern shows 26.6% matching. And the case of HH shows 16.6% matching. In order to observe the change of HU value between HCC and HH, each average values and standard deviation was confirm and as a result, it shows the lagre difference between artery and portal phase in lesion.(HCC$19.76{\pm}23.52$, HH$60.23{\pm}29.43$). And it shows the 76.6% matching in HCC and 80.0% matching in HH. Thorough this study, to suggest a HU value as objective analysis method and if the anlaysis method was used in clinical will assist in the diagnosis.

A New Carrier Recovery Algorithm Usign $\theta$-matching method for QAM Demodulator ($\theta$-정합을 이용한 QAM 복조용 Carrier Recovery)

  • 박휘원;장일순정차근조경록
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.179-182
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    • 1998
  • Carrier recovery, the process of recoverying the carrier in receiver, removes the phase difference between VCO and the received signal. However, the conventional structure of carrier recovery cannot be applied to multi-level QAM demodulator because of the increasing decision interval and the complexity of control as the number of symbol increases. In this paper, we suggest a new carrier recovery algorithm using $\theta-matching$ algorithm for multi-level QAM demodulation to overcome this problem and analysis the performance and implement it.

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Real Time CUSUM Control of Plasma Impedance Matching Network (플라즈마 임피이던스 정합망 실시간 CUSUM 제어)

  • Kim, Woo-Suk;Kim, Byung-Whan
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1844-1845
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    • 2007
  • A CUSUM control chart was used to monitor semiconductor plasma equipment. The performance of plasma monitoring was evaluated with various combinations of design variables involved in CUCUM control chart. Experimental data collected by using a real-time matching monitoring system include electrical positions of impedance and phase positions, and reflected power. The evaluation revealed that by determining specific design variables plasma states could be more strictly monitored.

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FEM analysis of Ti:$LiNbO_3$ optical modulator's traveling-wave electrodes and estimation of modulation band-width (Ti:$LiNbO_3$ 진행파 광변조기의 FEM 전극해석 및 대역폭 예측)

  • 김창민;한상필
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.32A no.2
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    • pp.96-110
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    • 1995
  • Traveling-wave electrodes for the high-speed Ti:LiNbO$_{3}$ modulators are designed. For a solution to the problems of 1) phase-velocity mismatching between the optical wave and the Modulating M/W, 2) M/W electrode characteristic impedance mismateching, we assume devices with 1$\mu$m thick SiO$_{2}$ buffer layer between the electrode and the Ti:LiNbO$_{3}$ substrate. The electrode analyses are performed by the FEM using the second-order triangular elements. The optimum design parameters to satisfy the phase-velocity matching and the characteristic impedance matching are sought for. By use of the analyses' results, a Mach-Zehnder optical modulator with a CPW electrode is designed as an example. the band-width estimation is also illustrated.

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Phase Matching of Pressure Wave in a Drop-On-Demand Inkjet Print Head (요구 적출형 잉크젯 프린트 헤드에서의 압력파 위상 정합)

  • Kim, Myong-Ki;Hwang, Jun-Young;Lee, Sang-Ho;Kang, Kyung-Tae;Kang, Heui-Seok
    • Journal of the Korean Society for Precision Engineering
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    • v.25 no.9
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    • pp.116-125
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    • 2008
  • Inkjet printing technology with a drop-on-demand (DOD) inkget head technology has been recognized as one of versatile and low cost manufacturing tools in the electronics industry. Concerned with control of driving signal, however, general strategy to optimize jetting stability has not been understood well, because of the inherent complex multi-physics nature in inkjet phenomena. Motivated by this, present study investigates the effect of driving waveforms of piezoelectric head on jetting characteristics of DOD inkjet system focused on jetting stability with phase matching of pressure waves in the print head. The results show that velocities and volumes of the ink jetted droplets were linear relations with the driving signal's maximum voltage, while periodic behaviors are observed with the driving signal's pulse widths.

Phase Matching of Pressure Wave in a Drop-On-Demand Inkjet Print Head (요구 적출형 잉크젯 프린트 헤드에서의 압력파 위상 정합)

  • Kim, Myong-Ki;Hwang, Jun-Young;Lee, Sang-Ho;Kang, Kyung-Tae;Park, Mun-Su
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.1444-1449
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    • 2007
  • Inkjet printing technology with a drop-on-demand (DOD) inkjet head technology has been recognized as one of versatile and low cost manufacturing tools in the electronics industry. Concerned with control of driving signal, however, general strategy to optimize jetting stability has not been understood well, because of the inherent complex multi-physics nature in inkjet phenomena. Motivated by this, present study investigates the effect of driving waveforms of piezoelectric head on jetting characteristics of DOD inkjet system focused on jetting stability with phase matching of pressure waves in the print head. The results show that velocities and volumes of the ink jetted droplets were linear relations with the driving signal's maximum voltage, while periodic behaviors are observed with the driving signal's pulse widths.

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Simultaneous Generation of Orthogonally Polarized Signals in an Optical Parametric Oscillator Based on Periodically Poled Lithium Niobate

  • Kumar, CH. S.S. Pavan;Kim, Byoung Joo;Kim, Deok Woo;Cha, Myoungsik
    • Current Optics and Photonics
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    • v.4 no.1
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    • pp.63-68
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    • 2020
  • We built an optical parametric oscillator (OPO) generating orthogonally polarized signals at different wavelengths simultaneously, based on a periodically poled lithium niobate (PPLN) crystal. The OPO was pumped by ns-pulses at 1.064 ㎛ from a diode-pumped solid-state laser, where we found the type-0 and the type-1 quasi-phase matching conditions were satisfied simultaneously in the PPLN crystal. This enabled us to create a coherent light source which can emit dual signals which could be accessed easily by rotating a polarizer.

A Study on Phase-Matching of Electrodes for Traveling-Wave Electrooptic Integrated Devices (진행파형 전기광학 집적소자에 대한 전극의 위상정합에 관한 연구)

  • 정홍식;이두복;정영식
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.29A no.8
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    • pp.41-48
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    • 1992
  • The characteristics of traveling-wave electrodes for high-frequency electroptic integrated devices are described from the view point of improvement of phase-matching based on the conformal mapping method. Specific calculations of the characteristic impedance, effective microwave index, and eletrode loss for asymmetric coplanar strip(ACPS) and coplanar waveguide(CPW) electrode structures are presented as a function of the geometric electrode parameters including the electrode thickness and buffer layer thickness. 5-10(x10S0-6Tm) thick Au-ACPS electrodes were successfully fabricated by electroplating and ECR etcher. The improvement of modulation bandwidth can be theoretically observed from the combination of electrode and buffer layer thickness.

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A Honey-Hive based Efficient Data Aggregation in Wireless Sensor Networks

  • Ramachandran, Nandhakumar;Perumal, Varalakshmi
    • Journal of Electrical Engineering and Technology
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    • v.13 no.2
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    • pp.998-1007
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    • 2018
  • The advent of Wireless Sensor Networks (WSN) has led to their use in numerous applications. Sensors are autonomous in nature and are constrained by limited resources. Designing an autonomous topology with criteria for economic and energy conservation is considered a major goal in WSN. The proposed honey-hive clustering consumes minimum energy and resources with minimal transmission delay compared to the existing approaches. The honey-hive approach consists of two phases. The first phase is an Intra-Cluster Min-Max Discrepancy (ICMMD) analysis, which is based on the local honey-hive data gathering technique and the second phase is Inter-Cluster Frequency Matching (ICFM), which is based on the global optimal data aggregation. The proposed data aggregation mechanism increases the optimal connectivity range of the sensor node to a considerable degree for inter-cluster and intra-cluster coverage with an improved optimal energy conservation.