• Title/Summary/Keyword: Phase response

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Response Time Optimization of DVR for 3-Phase Phase-Controlled Rectifier (3상 위상제어 정류기를 위한 DVR의 반응시간 최적화)

  • Park, Chul-Woo;Joung, Sookyoung;Ryu, Jee-Youl;Lee, Dae-Seup
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.3
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    • pp.195-201
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    • 2013
  • In this paper, we present optimization technique for the response time of DVR (Dynamic Voltage Restorer) and the possible compensation range of voltage dip by the DVR system. To protect 3-phase phase-controlled rectifier from voltage dip, DVR system needs to have optimum response time as an important design factor. Although the fast response time of DVR ensures wider range of voltage dip, DVR controller has so high cost and poor stability. This paper proposes DVR system with optimum response time required for certain intensity of voltage dips and good stability to support possible compensation range of voltage dip. Proposed technique showed optimum response time and good stability for overall system. We believe that proposed technique is reliable and useful in DVR design.

A Study on the Diagnosis of Secondary Battery by Phase Response (위상응답에 의한 이차전지의 진단에 관한 연구)

  • Park, Seung-Gon;Kang, Dea-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.19 no.4
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    • pp.99-104
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    • 2019
  • It was proposed the use of an inducive element to measure the SOH of a secondary battery by phase response. As a result of simulating the Randles equivalent model of a secondary battery, the inductive element used as the load has a high response characteristic and increases the maximum phase response frequency band. In order to obtain the frequency band in which the phase response characteristic of the secondary battery is well observed, the phase response was measured with the change of the inductance value of the inductive element, 33uH,49mohm inductive element with the maximum phase response at 631Hz was used. The phase response measurements for secondary battery with different SOH showed that the phase response for each 20% of SOH showed a difference of about 3.8(degree), enabling the SOH diagnosis of secondary battery by the phase measurement for the inductive element.

A Study on the Reliability of DVR in a 3-Phase Phase-Controlled Rectifier

  • Kim, Woo-Hyun;Park, Chul-Woo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.11
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    • pp.54-61
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    • 2012
  • This study investigated the relationship between the response time of DVR (Dynamic Voltage Restorer) and the possible compensation range for voltage dips by the DVR system which protects the 3-phase phase-controlled rectifier from said dips. As a result, the permissible range of voltage dip is presented in a 3-phase phase-controlled rectifier. When the DVR compensates for voltage dip, the range of voltage dip can be compensated according to the DVR's response time. Using the proposed method, DVR response time can be determined from the parameters of the 3-phase phase-controlled rectifier and the possible compensatory range of voltage dip, while at the same time it is possible to use a control system having an appropriate speed. Therefore, the use of excessively fast equipment can be avoided, improving the stability of the overall system. The reliability of the DVR concerning the 3-phase phase-controlled rectifier can be verified by simulation.

A study on the permissible range of voltage dips and the response time of DVR in 3-phase phase-controlled rectifier (3상 위상제어 정류기에서 DVR의 응답시간과 허용 가능한 순시저전압의 범위에 대한 연구)

  • 한무호;권우현;박철우
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.4
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    • pp.325-333
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    • 2004
  • It is investigated that the relation between the response time of DVR(Dynamic Voltage Restorer) and the possible compensation range of voltage dip by the DVR system which protects the 3-phase phase-controlled rectifier from voltage dip. As a result, the permissible range of voltage dip is presented in the 3-phase phase-controlled rectifier, and it is presented that the range of voltage dip which can be compensated according to the DVR s response time. when the DVR compensates voltage dip, Using the proposed method, the DVR s response time can be determined from the parameters of 3-phase phase-controlled rectifier and the possible compensation range of voltage dip, and it is possible to use the control system which have an appropriate speed. Therefore, the use of excessively fast device can be avoided, and the stability of the overall system is improved. Also the reliance of DVR about the 3-phase phase-controlled rectifier can be verified.

Inhalation Exposure to Nickel Hydroxide Nanoparticles Induces Systemic Acute Phase Response in Mice

  • Kang, Gi-Soo;Gillespie, Patricia Anne;Chen, Lung-Chi
    • Toxicological Research
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    • v.27 no.1
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    • pp.19-23
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    • 2011
  • It has been proposed that acute phase response can be a mechanism by which inhaled particles exert adverse effects on the cardiovascular system. Although some of the human acute phase proteins have been widely studied as biomarkers of systemic inflammation or cardiovascular diseases, there are only a few studies that investigated the role of serum amyloid P (SAP), a major acute phase protein in mice. In this study, we investigated the changes in SAP, following inhalation exposure to nickel hydroxide nanoparticles (nano-NH). We conducted 1) acute (4 h) exposure to nano-NH at 100, 500, and $1000\;{\mu}g/m^3$ and 2) sub-acute (4h/d for 3d) exposure at $1000\;{\mu}g/m^3$, then measured serum SAP protein levels along with hepatic Sap mRNA levels. The results show that inhaled nano-NH can induce systemic acute phase response indicated by increased serum SAP levels and hepatic Sap mRNA levels. To the best of our knowledge, this is the first study showing induction of SAP in response to repeated particle exposure, and the results suggest that SAP can be used as a biomarker for systemic inflammation induced by inhaled particles.

Effect of Dietary Krill Meal on the Performance of Broiler Chicks During the Acute Phase Response (급성기 반응중인 육계 병아리의 생산성에 미치는 사료 중 크릴 밀의 영향)

  • Koh, T.S.;Im, J.T.;Park, I.K.;Kim , J.H.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.173-182
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    • 2004
  • The effect of dietary Antartic krill(Euphausia Superba) meal on the performance of broiler chicks during the acute phase responses was studied. One d-old male broiler chicks(Avian) were fed on the experimental basal (0.0 % krill meal), and 0.5 and 1.0 % krill meal diets, and then the acute phase response were activated by injecting Salmonella typhymurium lipopolisaccharide(LPS) three times i. p. at 8, 10 and 12 day of age. The 1.0% krill meal diet group had reduced daily gain and feed efficiency during the acute phase response of the 2nd week of age, while during recovery from the acute phase response of the 3rd week of age the lowered performance disappeared. The acute phase response increased the relative weight of liver and spleen, and dietary krill meal enhanced the activities of MnSOD and Cu/ZnSOD in liver and erythrocyte cytosols during the acute phase response, although neither the acute phase response or dietary krill meal affected significantly PHA-p hypersensitivity. The results indicated that dietary krill meal affected the performance and SOD activity of broilers chicks during the acute phase response.

Effect of the Acute Phase Response on the Performance and Superoxide Dismutase Activity in Broiler Chicks Fed on Dietary Krill Meal (사료 중 크릴 밀을 급여한 육계의 생산성과 SOD 활성에 미치는 급성기 반응의 영향)

  • Park, I.K.;Kim, J.H.;Im, J.T.;Koh , T.S.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.183-192
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    • 2004
  • Two experiments were conducted to examine the effects of the acute phase response on the performance and superoxide dismutase(SOD) activities in liver and erythrocyte of broiler chicks fed dietary krill meals A and B in experiment 1 and krill meal A in experiment 2. The experimental diets are basal diet based on yellow corn and soybean meal and diets substituted 2.0% of krill meal A or B with soybean meal of the basal diet, respectively. Day-old birds fed on the experimental diets and the acute phase response(immunological stress) was activated in the birds on 8-day of age by alternate day injection i.p. with 3 doses the Salmonella typhymurium lipopolysaccharide(LPS) in saline. The values during the acute phase response were compared with those controls injected with saline. The performance; daily gain, feed intake, and feed efficiency were different between dietary krill meal A and B in birds during the acute phase response and in the control. The acute phase response increased relative liver and spleen weights. Recovery of birds from the immunological stress was different between krill meals. Dietary krill meals increased activities of MnSOD and Cu/ZnSOD in erythrocyte cytosols during the actute phase response. Dietary krill meals did not affect the PHA-p response. The results indicated that the dietary krill meals may accentuate oxidative stress during the acute phase response.

Impulse Response Filtration Technique for the Determination of Phase Velocities from SASW Measurements (SASW시험에 의한 위상속도 결정을 위한 임펄스 응답필터 기법)

  • ;Stokoe, K.H., Il
    • Geotechnical Engineering
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    • v.13 no.1
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    • pp.111-122
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    • 1997
  • The calculation of phase velocities in Spectral-Analysis -of-Surface -Waves (SASW) meas urements requires unwrapping phase angles. In case of layered systems with strong stiffness contrast like a pavement system, conventional phase unwrapping algorithm to add in teger multiples of 2n to the principal value of a phase angle may lead to wrong phase volocities. This is because there is difficulty in counting the number of jumps in the phase spectrum especially at the receiver spacing where the measurements are in the transition Bone of defferent modes. A new phase interpretation scheme, called "Impulse Response Fil traction ( IRF) Technique," is proposed, which is based on the separation of wave groups by the filtration of the impulse response determinded between two receivers. The separation of a wave group is based on the impulse response filtered by using information from Gabor spectrogram, which visualizes the propagation of wave groups at the frequency -time space. The filtered impulse response leads to clear interpretation of phase spectrum, which eliminates difficulty in counting number of jumps in the phase spectrum. Verification of the IRF technique was performed by theoretical simulation of the SASW measurement on a pavement system which complicates wave propagation.opagation.

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Effect of Vesicle Curvature on Phospholipase D Reaction-Induced-Rupture

  • Lee, Gil Sun;Park, Jin-Won
    • Bulletin of the Korean Chemical Society
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    • v.34 no.11
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    • pp.3223-3226
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    • 2013
  • Spherical phospholipid-bilayers, vesicles, were prepared using the layer-by-layer double emulsion technique, which allows the bilayer to be formed asymmetrically. On the outer layer of the vesicles, the phospholipase D (PLD) reacted to convert phosphatidylcholine (PC) to phosphatidic acid (PA). The reaction induced the curvature change of the vesicles, which eventually led to rupture. The response time from the time of PLD injection to the time of rupture was measured against different vesicle curvatures and the outer layer phase, using the fluorescence intensity change of a pH-sensitive dye encapsulated within the vesicles. The effect of the vesicle curvature on the response was observed to be more significantly dramatic at the solid phase, compared to the liquid phase. Furthermore, in the solid phase, the response time was faster for 80 and 155 nm vesicles and, slower for 605 nm vesicles than similarly sized vesicles in the liquid phase vesicles. This difference in the response time was thought to result from the configuration determined by the phase difference and the PLD behavior.

Effect of Dietary Brown Seaweed Levels on the Protein and Energy Metabolism in Broiler Chicks Activated Acute Phase Response (급성기 반응을 활성화한 육계 병아리에서 사료중 미역 제품 수준이 단백질과 에너지 대사에 미치는 영향)

  • Koh, T.S.;Im, J.T.;Park, I.K.;Lee, H.J.;Choi, D.Y.;Choi, C.J.;Lee, H.G.;Choi, Y.J.
    • Journal of Animal Science and Technology
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    • v.47 no.3
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    • pp.379-390
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    • 2005
  • Effects of dietary brown seaweed product levels on performance and metabolism of protein and energy were investigated in broiler chicks that were activated the acute phase response. One day old chicks were fed diets containing either 0.0(basal), 1.0, 2.0 or 4.0 % brown seaweed products for 3 weeks. The acute phase response was activated by injecting i.p. the Salmonella typhimurium lipopolysacharide(LPS) at $2^{nd}$ week of age. The acute phase response lowered nitrogen balance(NB)/ $kg^{0.75}$ (metabolic body size) and highered dietary ME values in birds fed diets containing brown seaweed product. Increase in dietary brown seaweed products levels lowered daily gain, and NB, uric acid nitrogen(UAN) excretion and ME utilization per $kg^{0.75}$ in chicks with the acute phase response. But the dietary brown seaweed product level did not affect the performance of 3 Week old broiler chicks that experienced the acute phase response. And the brown seaweed products 1.0 and 2.0 % diets lessened the feed intake reduction caused by the acute phase response in broiler chicks. The brown seaweed 2.0% diet increased NB / g diet or $kg^{0.75}$ and decreased the excretion of UAN/g diet or $kg^{0.75}$. This result indicated that the brown seaweed was able to interact with the acute phase response and increased protein retention via decreased breakdown of protein in birds fed brown seaweed 2.0% diet.