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Development of Dynamic Voltage Restorer System Considering Characteristics of EDLC (EDLC의 특성을 고려한 동적전압보상시스템의 개발)

  • Lee, Sang-Cheol;Seo, Il-Dong
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.59 no.3
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    • pp.288-292
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    • 2010
  • Recently, in energy storage system, the EDLC is paid attention as a new environmentally friendly energy storage element. This capacitor has higher energy density than the electrolytic capacitor. Also, this capacitor has a lot of advantage such as no maintenance, longer life cycle and faster charge-discharge time than the battery system. But the EDLC must have a each charge-discharge controller to effectively control, an energy design method circuit to use effectively energy, and several compensation techniques to control a optimal operating. In this respect, this study suggests major parameters to effectively represent the characteristics of EDLC, the measurement methods of those parameters have been investigated with experiments, and the interpretation about the buck/boost DC/DC converter for the operation of EDLC.

Chemical Control of Gray Mold in Scutellaria baicalensis Georg

  • Kwon, Byung-Sun;Shin, Dong-Young
    • Plant Resources
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    • v.8 no.2
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    • pp.130-134
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    • 2005
  • This study was conducted to evaluate the control effect of fungicides on control of Gray mold, growth characteristics, and root yield in the cultivation of Scutellaria baicalensis after barley cropping. All fungicides treated had no effect on the growth and flowering rate of Scutellaria baicalensis. All seed disinfectants had no effect on the growth and flowering date of Scutellaria baicalensis Georg. The major seed disinfectants were Benomyl Wp, $20\%$, Captan Wp, $50\%$, Hymexazol Ec, $30\%$, Carboxin D, $37.5\%$. Dry root yield were increased largely with Benomyl Wp, $20\%$, seed disinfectant than the other seed disinfectants had no injury with standard dosage. On the other hand, all seed disinfectants had slight injury in the double dosage level for the Scutellaria baicalensis Georg.

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Selecting of Useful Chemicals Reducing of Leaf Blight on Job's Tears (Coix lachry-ma-jobi L. Var.)

  • Kwon, Byung-Sun
    • Plant Resources
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    • v.8 no.2
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    • pp.161-166
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    • 2005
  • This study was conducted evaluate the control effect of fungicides on control of Leaf blight, growth characteristics, and dry yield in the cultivation of Job's tears. All fungicides treated had no effect on the growth of Job's tears. The major fungicides were mancozeb Wp, $75\%$, chlorothalonil Wp, $75\%$, dithianon Wp, $43\%$, difenoconazole Wp, $10\%$, benomyl Wp, $50\%$, and propineb Wp, $70\%$. Dry seed yield were increased largely with chlorothalonil Wp, $75\%\;(33g/20\ell)$, fungicide than the other fungicides and control. All fungicides had no injury with standard dosage. On the other hand all fungicides had slight injury in the double dosage level for the Job's tears.

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Immunological Studies of Ginseng (인삼의 면역학적 연구)

  • Soldati Fabio
    • Proceedings of the Ginseng society Conference
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    • 1988.08a
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    • pp.108-114
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    • 1988
  • One of the major effects of Panax ginseng the best known traditional medicine in the Far East. is the enhancement of host resistance against infections. which could depend on an influence from the immune system. The studies presented have been carried out with extracts from Korean ginseng roots which were examined for immunological activity in vitro and in vivo. The results obtained in a double-blind clinical study with humans confirmed results obtained in vitro with human granulocytes and in vivo with mice. The ginseng extracts showed a significant stimulatory action on the immune response.

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Experimental Study on Bond Stress-Slip Behavior of Reinforced Concrete Member Under Repeated Loading Considering Steel Corrosion (반복하중 하에서 철근부식을 고려한 철근콘크리트 부재의 부착응력-슬립 거동에 관한 실험적 연구)

  • Kim, Chul-Min;Kim, Jee-Sang;Park, Jong-Bum;Chang, Sung-Pil
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.545-548
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    • 2006
  • This study includes the experimental investigation on the fatigue-bond behavior with respect to the various rates of steel corrosion. Major criteria of test variables are the rates of steel corrosion by chloride ion and the ratio of the applied stress to the bond failure stress. According to the test results, the slip versus number of load cycles relation was found to be approximately linear in double logarithmic scale, not only without steel corrosion but also with steel corrosion. This research will be helpful for the realistic durability design and condition assessment of reinforced concrete structures.

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The Design Simulation for Manufacture of High Frequence Ceramic Filter (고주파용 세라믹 필터의 제작을 위한 디자인 해석)

  • 이수호;석정영;류기흥;사공건;윤광희;류주현;박창엽
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.418-421
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    • 2001
  • The ceramic filters were developed using technology similar to that of quartz crystal and electro- mechanical filter. However, the key to this development involved the theoretical analysis of vibration modes and material improvements of piezoelectric ceramics. The primary application of ceramic filters has been for consumer-market use. Accordingly, a major emphasis has involved mass production technology, leading to low-priced devices. A typical ceramic filter includes monolithic resonators and capacitors packaged in unique configurations. Nakazawa developed a double-mode resonator as two acoustically coupled single resonators. And he developed 10.7MHz crystal filters using multi-energy trapping mode of thickness shear vibration. He succeeded in realizing a two-pole band pass filter response without external inductance by splitting a dot electrode to creak coupled symmetric and anti- symmetric vibration modes. Accordingly, the simulation for ceramic (inter were important. So that, this paper were investigated the pass frequency of filter on the electrode length and thickness of ceramic.

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Robust Decoupling Digital Control of Three-Phase Inverter for UPS (3상 UPS용 인버터의 강인한 비간섭 디지털제어)

  • Park, Jee-Ho;Heo, Tae-Won;Shin, Dong-Ryul;Roh, Tae-Kyun;Woo, Jung-In
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.49 no.4
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    • pp.246-255
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    • 2000
  • This paper deals with a novel full digital control method of the three-phase PWM inverter for UPS. The voltage and current of output filter capacitor as state variables are the feedback control input. In addition, a double deadbeat control consisting of a d-q current minor loop and a d-q voltage major loop, both with precise decoupling, have been developed. The switching pulse width modulation based on SVM is adopted so that the capacitor current should be exactly equal to its reference current. In order to compensate the calculation time delay, the predictive control is achieved by the current·voltage observer. The load prediction is used to compensate the load disturbance by disturbance observer with deadbeat response. The experimental results show that the proposed system offers an output voltage with THD less than 2% at a full nonlinear load.

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Comparative Study on Transient Stability Improving Capability of Series and Shunt Compensation (비용함수에 의한 직병렬보상장치의 과도안정도 향상 특성 비교)

  • Choi, Kyu-Hyoung;Jeoug, Chang-Yang;Oh, Tae-Kyoo
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.655-657
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    • 1996
  • The objective of this paper is to compare the series and shunt approaches of controlled reactive power compensation to improve power system transient stabilities. Including main circuit considerations of series and shunt compensators, application aspects are thought to have major impacts on efficiency and economy of the installation of the compensators. The concept is studied by means of EMTP simulations on one machine-Infinite Bus Test System which consists of a 612MVA steam turbin generator and transformer and double circuit 345KV transmission line. Idealized dynamic models of Thyristor Controlled Series Compensation and Shunt Compensation are used for the comparative study of the series and shunt compensation approach to damp power system oscillations.

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The Generation of True Orthophotos from High Resolution Satellites Images

  • Chen, Liang-Chien;Wen, Jen-Yu;Teo, Tee-Ann
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.885-887
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    • 2003
  • The purpose of this investigation is to generate true orthophotos from high resolution satellite images. The major works of this research include 4 parts: (1) determination of orientation parameters, (2) generating traditional orthophotos using terrain model, (3) relief correction for buildings, and (4) process for hidden areas. To determine the position of satellites, we correct the onboard orientation parameters to fine tune the orbit. In the generation of traditional orthophotos, we employ orientation parameters and digital terrain model(DTM) to rectify tilt displacements and relief displacements for terrain. We, then, compute relief displacements for buildings with digital building model (DBM). To avoid double mapping, we detect hidden areas. Due to the satellite’s small field of view, an efficient method for the detection of hidden areas and building rectification will be proposed in this paper. Test areas cover the city of Kaohsiung in southern Taiwan. Test images are from the QuickBird satellite.

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Effects of Mecoprop Wettable Powder Concentrations on Growth and Yield of Flax

  • Kwon, Byung-Sun
    • Plant Resources
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    • v.7 no.1
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    • pp.15-21
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    • 2004
  • This study was conducted to evaluate the effect of mecoprop-wp concentrations on weed control, growth characters and yield in flax, after 7cm and 14cm of plant height it to the field. The major weeds were Alopecurus aequalis var. a murensis (kom) ohwi, Persicaria hydropiper spach, Lamium amplexicaule L, Stellaria alsine Grimm var. undulata ohwi, Eleusine indica(L.) Gaertn. Flax yield were increased somewhat more with 250g/10a mecoprop-wp at 7cm of plant height than the other treatment and by hand weeding treatment of mecoprop-wp, 250g/10a at 7cm of plant height was slightly harmful for the flax with recommended concentration, On the other hand, all treatments were harmful in the double dosage level.

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