• Title/Summary/Keyword: Median power

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An analysis of the measured electric and magnetic fields of transmission lines in Korea (전국의 송전선로 전자계 측정치와 계산치와의 비교 분석)

  • Kim, S.B.;Cho, S.B.;Shin, K.Y.;Lee, D.I.;Kim, J.B.
    • Proceedings of the KIEE Conference
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    • 1999.07e
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    • pp.2368-2370
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    • 1999
  • A nationwide survey for electric and magnetic fields(EMFs) near overhead transmission lines has been conducted. The median values of the electric and magnetic fields of 208 transmission lines were 0.50 kV/m and 12.6 mG, respectively. The maximum values were 3.16 kV/m and 125 mG. The measured EMFs were compared with the calculated ones. The causes of the discrepancy between measured and calculated EMFs are also discussed.

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A Study on Comparative Analysis of Power Consumption Characteristics and the revulsion of investment on the application of a BESS in Subway Substation (도시철도 변전소 단위구간의 전력사용 실태 및 피크제어용 BESS 도입에 따른 경제성 분석)

  • Jung, Hyun-Ki;Kim, Se-Dong;Kim, Jae-Chul
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.28 no.6
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    • pp.85-90
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    • 2014
  • This paper shows a reasonable demand power, that was made by the systematic and statistical way considering actual conditions, such as investigated transformer capacity and peak power for the last 6 years of subway substation customer as to AMR. In this dissertation, it is necessary to analyze the key features and general trend from the investigated data. It made an analysis of the feature parameters, such as average, standard deviation, median, maximum, minimum and thus it was carried by the linear and nonlinear regression analysis. And we studied on the application of a BESS. Analysis showed that the revulsion of capital is about 3 years and 4 months.

Prediction Intervals for Day-Ahead Photovoltaic Power Forecasts with Non-Parametric and Parametric Distributions

  • Fonseca, Joao Gari da Silva Junior;Ohtake, Hideaki;Oozeki, Takashi;Ogimoto, Kazuhiko
    • Journal of Electrical Engineering and Technology
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    • v.13 no.4
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    • pp.1504-1514
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    • 2018
  • The objective of this study is to compare the suitability of a non-parametric and 3 parametric distributions in the characterization of prediction intervals of photovoltaic power forecasts with high confidence levels. The prediction intervals of the forecasts are calculated using a method based on recent past data similar to the target forecast input data, and on a distribution assumption for the forecast error. To compare the suitability of the distributions, prediction intervals were calculated using the proposed method and each of the 4 distributions. The calculations were done for one year of day-ahead forecasts of hourly power generation of 432 PV systems. The systems have different sizes and specifications, and are installed in different locations in Japan. The results show that, in general, the non-parametric distribution assumption for the forecast error yielded the best prediction intervals. For example, with a confidence level of 85% the use of the non-parametric distribution assumption yielded a median annual forecast error coverage of 86.9%. This result was close to the one obtained with the Laplacian distribution assumption (87.8% of coverage for the same confidence level). Contrasting with that, using a Gaussian and Hyperbolic distributions yielded median annual forecast error coverage of 89.5% and 90.5%.

A Study of Hood-Type Vertical Axis Wind Turbine Embedded to Highway Median Strip (도로 중앙분리대용 후드장식형 수직축풍력발전기 연구)

  • Lee, Jong-Jo;Lim, Jae-Kyoo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.1
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    • pp.24-34
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    • 2013
  • This paper introduces the study of hood-type wind turbine embedded on highway median strip. Recently, many studies are being made to apply to small wind turbine in city. This study is wind turbine producing electricity generated from the wind by running cars. In order to analyze wind generated by running cars, we measured experiments using running cars and buses. Also, using CFD and interpreter program, we analysis wind turbines performance and applied to the twist-sabonius blade. This wind turbine attached to safety lamp on the road is produced to use electricity generated through the wind tunnel experiment. In this paper results, this wind turbine system is expected to produce the power source installed the heat ray and safety lamps on the road.

The Effects of Hold-Relax and Active Stretching on Recoveries of Muscle Fatigue after Computer Work (컴퓨터 작업 후 유지-이완운동과 능동신장이 근피로 회복에 미치는 영향)

  • Lee, Hyun-Ok;Heo, Seong-Yong
    • PNF and Movement
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    • v.6 no.2
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    • pp.11-18
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    • 2008
  • Purpose : The purpose of this study was to identify that the effect of hold-relax and active stretching on recoveries of upper trapezius and sternocleidomastoid muscle fatigue after computer work. Methods : This study was conducted by 30 volunteer at the age of 23~33(resting group=10, hold-relax group=10, active stretching group=10). The muscle fatigue measured by tracing the median frequency(MDF) decrement from power spectrum analyses of EMG signals and the data were analyzed repeated ANOVA. Result : In case of upper trapezius, there was significant difference in group I,II and group II, III. In case of sternocleidomastoid, there was significant difference in group I,II and group I,III. Conclusion : The active stretching was effective for sternocleidomastoid and the hold-relax was effective for upper trapezius and sternocleidomastoid. The hold-relax was effective better than active stretching on recoveries of muscle fatigue.

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Shock Test Signal Analysis using Wavelets (웨이블렛을 이용한 충격신호분석)

  • 안호일
    • Journal of the Korea Institute of Military Science and Technology
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    • v.4 no.1
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    • pp.147-154
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    • 2001
  • The underwater explosion shock test is performed for the evaluation of the shock-resistant capability which is a very critical factor considering the survivability of the battle ship. Some measured signals have impulsive noise and gaussian white noise because of the unstable power supply system and the transient movement of cables during the underwater explosion shock test. The advanced shock signal analysis method which remove the noise of measured signal using the threshold policy of the median filter and the orthogonal wavelet coefficients are proposed. It is verified that the signal-to-noise ratio was improved about 30㏈ by the numerical simulation.

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Muscle Fatigue Nlonitoring Using a DSP Chip and PC (DSP칩과 PC를 이용한 근피로도 측정)

  • Cho, I. J.;Lee, J.;Choi, Y. H.;Kim, S. H.
    • Journal of Biomedical Engineering Research
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    • v.9 no.2
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    • pp.211-214
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    • 1988
  • As a muscular contraction is sustained, the power spectrum of the myoelectric signal is compressed into lower frequencies. The median frequency appears to be the prefered parameters to monitor this compression. This paper describes a technique and a device which provide an estimate of the median frequency using a TMS32020 DSP chip and IBM PC for tracking of this parameter. Results obtained from myoelectric signal are presented and discussed.

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Early Surgical Treatment of Pronator Teres Syndrome

  • Lee, Ho Jin;Kim, Ilsup;Hong, Jae Taek;Kim, Moon Suk
    • Journal of Korean Neurosurgical Society
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    • v.55 no.5
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    • pp.296-299
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    • 2014
  • We report a rare case of pronator teres syndrome in a young female patient. She reported that her right hand grip had weakened and development of tingling sensation in the first-third fingers two months previous. Thenar muscle atrophy was prominent, and hypoesthesia was also examined on median nerve territory. The pronation test and Tinel sign on the proximal forearm were positive. Severe pinch grip power weakness and production of a weak "OK" sign were also noted. Routine electromyography and nerve conduction velocity showed incomplete median neuropathy above the elbow level with severe axonal loss. Surgical treatment was performed because spontaneous recovery was not seen one month later.

Muscle fatigue monitoring using a DSP chip and PC (DSP칩과 PC를 이용한 근피로도 측정)

  • Cho, I. J.;Lee, J.;Choi, Y. H.;Kim, S. H.
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10a
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    • pp.714-717
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    • 1988
  • As a muscular contraction is sustained, the power spectrum of the myoelectric signal is compressed into lower frequencies. The median frequency appears to be the prefered parameters to monitor this compression. This paper describes a technique and a device which provide an estimate of the median frequency using a TMS32020 DSP chip and IBM PC for tracking of this parameter. Results obtained from myoelectric signal are presented and discussed.

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Presidential Agendas and the Voting Behavior of Presidential Party Representatives: Analysis of Presidential Support Votes in the 111-116th Congresses (미국 대통령 의제에 대한 여당의 투표 행태: 111-116대 의회 여당 하원의원들의 대통령지지투표 분석)

  • Lee, Jongkon
    • American Studies
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    • v.44 no.1
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    • pp.81-112
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    • 2021
  • As polarization intensified in the United States, the voting support of the presidential party lawmakers has become the most important source of power for the president. The presidential party has been believed to legalize the president's agenda in a unified government and prevent legislation opposed by the president from being passed by the Congress within a divided government. However, even under party polarization, all the lawmakers and factions of the presidential party have not voted in accordance with the president's policy preferences. Statistical analysis shows that lawmakers who corresponded to the ideology median of the presidential party most strongly supported the president's agendas during the unified government. However, lawmakers with extreme ideologies voted more actively for the president than those with median ones during the divided government. Furthermore, this trend has been amplified regarding ideological factions.