• 제목/요약/키워드: peak

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다중레이트 필터링 기법을 이용한 맥파전달시간 추정 (Estimation of PTT (Pulse Transit Time) by Multirate Filtering Analysis)

  • 김현태;김정환;김경섭;이재호;이정환
    • 전기학회논문지
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    • 제62권7호
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    • pp.1020-1026
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    • 2013
  • Multirate filtering process on the biological signals like Electrocardiogram (ECG) and Photoplethysmogram (PPG) can be defined as the digital signal processing algorithm in which the sampling rate varies to omit or interpolate the intermediate values between the sampled data. With this aim, we suggest a new multirate filtering algorithm by deleting the extraneous data to eliminate the unwanted degradations such as granular noise due to the usage of high sampling frequency and simultaneously to detect the fiducial features of ECG and PPG with reducing the complexity of resolving fiducial points such as R-peak, Pulse peak and Pulse Transit Time (PTT). After the experimental simulations performed, we can conclude the fact that we can detect the fiducial features of ECG and PPG signal in terms of R-peak, Pulse peak and PTT without the loss of accuracy even if we do not maintain the original sampling frequency.

피크전류 제한 기능을 갖는 초전도한류기의 계통 적용에 따른 보호기기간 동작특성 분석 (Analysis on the Operational Characteristic between the Protective devices and Superconducting Fault Current Limiter with a Peak Current Limiting Function in the Power Distribution System)

  • 조용선;김진석;김재철;임성훈
    • 조명전기설비학회논문지
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    • 제26권11호
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    • pp.75-80
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    • 2012
  • In this paper, the operational characteristics due to the introduction of the superconducting fault current limiter(SFCL) with a peak current limiting function were analyzed in the power distribution system. The parallel structure of the superconducting element can operate the peak current limiting function depending on the transient amplitude of fault current. We studied the operating characteristics of the introduction of the SFCL with a peak current limiting function in the power distribution system. Furthermore, we were analyzed between the SFCL with a peak current limiting function and the protection devices in the power distribution system, through the short circuit experiments.

전력예비율과 전기요금, 신재생, 경제성장, 동·하계 동시피크 간 인과관계 연구 : OECD 패널 분석 (A Study on the Causality between Electric Reserve Margin, Electricity Tariff, Renewable Energy, Economic Growth, and Concurrent Peak in Winter and Summer: OECD Panel Analysis)

  • 이중호;박경민;박중구
    • 전기학회논문지
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    • 제67권11호
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    • pp.1415-1422
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    • 2018
  • In Korea, prior to 2011, the electric reserve margin followed the probabilistic reliability view and the planning reserve margin had been operated at about 15% based on the assumption that power outage was permitted within 0.5 days a year. However, after experiencing the shortage of the electric generation capacity in Sept. 15, 2011, the planning reserve margin was selected as 22% to improve the reliability of the electric supply. In this paper, using panel data of 28 OECD countries over the period 2000-2014 we attempted to empirically examine the linkage between reserve margin, electricity tariffs, renewable energy share, GDP per capita, and summer / winter peak-to-peak ratios. As a result, all four independent variables have been significant for the electric reserve margin, and in particular, we found that countries with similar peaks in winter and summer have operated 4.3% higher reserve margin than countries experiencing only summer peak.

전력 케이블용 저밀도 폴리에틸렌의 냉각 조건에 따른 기계적 및 유전손실에 관한 연구 (A study on the Dynamic Mechanical and Dielectric Loss according to Quenched Condition in Low Density Polyethylene fer Power Cable)

  • 김재환;권병휘;박재준
    • 한국조명전기설비학회지:조명전기설비
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    • 제6권5호
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    • pp.27-37
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    • 1992
  • We studied the dielectric and dynamic mechanical losses according to the quenching condition in low density polyethylene being used to power cables. According to severe quenching condition, characteristics of the temperature in internal friction los peak have decreased the magnitude of loss peak as amorphous region lengthen. From now on, the frequency dependent characteristics of dielectric loss have investigated at room temperature, and the dielectric loss peak due to interface polarization, between crystal and amorphous region, occurs about 30[Hz], and that, the peak due to orientation polarization in correspondence to the loss peak in internal friction has observed at about 3 [MHz]. As quenching velocity increased, the effect on quenching condition about the dielectric loss has decreased the magnitude of the loss peak. Thus, estimation has been carried out on the activation energies nd the degree of crystallinity by means of X-ray diffraction are obtained as follows: room quenching : 26.4 [kal/mole] and 54.73 [%], ice quenching : 25.6 [kcal/mole] and 48.47 [%], liquid nitrogen quenching specimens : 22.56 [kcal/mole] and 40.95 [%].

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앙상블 민감도를 이용한 2003년 8월 6일 집중 호우 역학 분석 (Ensemble Sensitivity Analysis of the Heavy Rainfall Event Occurred on 6th August 2003 over the Korean Peninsula)

  • 노남규;김신우;하지현;임규호
    • 대기
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    • 제23권1호
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    • pp.23-32
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    • 2013
  • Ensemble sensitivity has been recently proposed as a method to analyze the dynamics of severe weather events. We adopt it to investigate the physical mechanism which caused the heavy rainfall over the Korean Peninsula on 6th August 2003. Two rainfall peaks existed in this severe weather event. The selected response functions are 1 hour accumulated rainfall amount of each rainfall peak. Sensitivity fields were calculated using 36 ensemble members which were generated by WRFDA. The sensitive regions for the first rainfall peak are located over the Shandong Peninsula and the Yellow Sea at 12 hours before the first rainfall peak. However, the 12-h forecast sensitivity for the second rainfall peak is revealed near Typhoon ETAU (0310) and midlatitude trough. These results show that the first rainfall peak was induced by low pressure which located over the northern part of the Korean Peninsula while the second rainfall peak was caused by the interaction between typhoon ETAU and midlatitude trough.

마이크로파 플라즈마의 광방출 스펙트럼 (optical emission spectra of microwave plasma)

  • 박상현;구효근;심정봉;김경환;박재윤;이덕출
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
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    • pp.895-897
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    • 1998
  • The optical spectra of microwave plasma by four kinds of gases($N_2$, $N_2-CH_4$, $H_{2}-CH_{4}$ and Air-$CH_4$) have been measured for investigating 388.4[nm] peak which has the same intensity as $H_{\alpha}$(656.4[nm]) peak. A 388.4[nm] peak by $N_2$ plasma, $N_{2}-CH_{4}$ plasma and Air-$CH_4$ plasma may be CN peak because it is with 337.1, 357.8 and 316.0[nm] peaks by $N_2$. And a 388.4[nm] peak by $H_{2}-CH_{4}$ plasma without by $N_2$ 337.1, 357.8 and 316.0[nm] peaks may be CH peak. In the investigation results for optical spectra by $H_{2}-CH_{4}$ plasma and $H_{2}-CH_{4}-O_{2}$ plasma, the density of hydrogen atom was increased because oxygen decompose hydrogen molecules in $H_{2}-CH_{4}$ plasma with oxygen. These hydrogen atom decompose $CH_4$ and increase CH radical. And the crystalline of deposited diamond was good and the growth rate increased.

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양식 진주의 특성평가 (The estimation characteristics of cultured pearls)

  • 오정욱;김종식;최종건;김판채
    • 한국결정성장학회지
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    • 제13권6호
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    • pp.315-319
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    • 2003
  • 양식된 해수진주와 담수진주의 품질, 수량, 색상 등과 특성을 알아보았다. XRF 측정에서는 Ca 화합물이 주성분이며 해수진주에서는 Sr이 담수진주는 Si, S, Ca, Mn, P 등의 원소가 더 많이 검출되었다. 이러한 차이는 해수와 담수에 녹아 있는 이온이 진주성분에 영향을 준 것으로 판단된다. FT-IR 측정에서 거의 동일한 구조적인 peak를 나타내지만 2344$\textrm {cm}^{-1}$에서 담수진주의 흡수대가 나타났다. 광원으로 He-Cd Laser 사용으로 455 nm에서 peak는 담수진주가 높았고, Ar Laser 사용으로 담수진주는 545 nm에서 해수진주는 570 nm에서의 peak가 높았다

피크전류제한 기능을 갖는 초전도한류기의 전류제한 특성분석 (Analysis on Current Limiting Characteristics of a Superconducting Fault Current Limiter (SFCL) with a Peak Currnt Limiting Function)

  • 한태희;임성훈
    • 한국전기전자재료학회논문지
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    • 제24권1호
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    • pp.47-51
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    • 2011
  • The superconducting fault current limiter (SFCL) with a peak current limiting function according to the initial fault current with the different amplitudes was suggested. The proposed SFCL, which consists of two limiting components, causes only the first superconducting element among two limiting components to be quenched in case that the initial fault current with the lower peak amplitude happens. On the other hand, the initial fault current with the higher peak amplitude makes both the superconducting elements of two limiting components to be quenched, which contributes to the peak current limiting function of the SFCL. To confirm the fault current limiting operation of the proposed SFCL, the short-circuit tests of the SFCL according to the fault angle were carried out and its effective fault current limiting operations could be discussed.

A Correction Method for the Peak Tailing Backgrounds for Accurate Isotope Ratio Measurements of Uranium in Ultra Trace Levels using Thermal Ionization Mass Spectrometry

  • Park, Jong-Ho;Choi, In-Hee;Park, Su-Jin;Lee, Myung-Ho;Song, Kyu-Seok
    • Bulletin of the Korean Chemical Society
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    • 제32권12호
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    • pp.4327-4331
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    • 2011
  • A new method in thermal ionization mass spectrometry (TIMS) was developed to correct peak tailing backgrounds in the isotope ratio measurements of uranium in ultra trace levels for higher accuracy. Two different uranium standard reference materials (U005 and U030) were used to construct databases of signal intensities at mass 234 u and mass 236 u, which correspond to the two uranium minor isotopes, and signal intensity of $^{238}U$. Correlations between peak tailing backgrounds and $^{238}U$ were obtained by least-squares regression on calculated backgrounds at mass 234 u and mass 236 u with respect to the signal intensity of $^{238}U$ followed by separation of the peak tails of the two major isotopes of uranium ($^{235}U$ and $^{238}U$), which enables us to obtain a master equation for peak tailing background correction on all kinds of samples. Verification of the correction method was carried out using U010 and IRMM-040a.

Performance Evaluation of MTF Peak Detection Methods by a Statistical Analysis for Phone Camera Modules

  • Kwon, Jong-Hoon;Rhee, Hyug-Gyo;Ghim, Young-Sik;Lee, Yun-Woo
    • Journal of the Optical Society of Korea
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    • 제20권1호
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    • pp.150-155
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    • 2016
  • To evaluate the autofocusing performance of recent mobile phone cameras, it is necessary to determine the peak position of the center field MTF (Modulation Transfer Function), -known as the through focus MTF- of the module. However, the MTF peak position found by conventional methods deviates from the ideal position due to the focus scanning resolution of mobile phone cameras. This inaccurate peak position results in false judgements of the optical performance, leading to yield losses or customer complaints. An increase in the focus scanning resolution can address this problem, but the manufacturing UPH (Unit per Hour) level will also unfortunately increase as well, resulting in a loss of manufacturing capabilities. In this paper, several fitting models are studied to find an accurate MTF peak position within a short period of time. With an analysis of a large amount of manufacturing data, it is demonstrated that the fitting methods can reduce false judgements and simultaneously increase the capabilities of the manufacturing system.