• Title/Summary/Keyword: Power Effect

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An Empirical Study on the Change in Market Power after Mergers & Acquisition (합병과 시장지배력의 관계분석)

  • Chung Bhum-Suk;Lee Jin
    • Management & Information Systems Review
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    • v.4
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    • pp.327-348
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    • 2000
  • There are three major motives for M&A, financial synergy effect, operating & managerial synergy effect, and tax effect. The purpose of this study is to prove the operating & managerial synergy effect of M&A. To do this, we analyze the market-ripple effect of M&A, focusing on the increase in market power. Specifically we use cross-sectional data from 1985 to 1998 to show whether a market power of mergers is higher than that of a matched non-merging control group. we use time series data to show whether a market power of merger is higher than that of pre-merger. Also we use the event study using market model to show the stock price movement after mergers. The result is that although revenue increase after mergers, profit of the firms does not improve after mergers. Also there is sufficient evidence to say that there is a cumulative abnormal return for the firms after mergers.

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Mechanical Strength Calculation of HVDC Valve Hall (HVDC시스템 밸브홀의 기계적 강도 계산)

  • Kim, Chan-Ki;Lee, Seong-Do;Kang, Ji-Won;Yoon, Yong-Beum
    • The Transactions of the Korean Institute of Power Electronics
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    • v.21 no.5
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    • pp.442-448
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    • 2016
  • This paper presents electromagnetic force effect of the conductor and insulator in the HVDC valve hall. This paper is based on IEC 60865, which is applicable to the mechanical and thermal effects of short-circuit currents. The paper contains procedures for the calculation of the electromagnetic effect on HVDC conductors and flexible conductors, as well as the thermal effect on HVDC conductors. The results are applied to the Godeok -Dangjin HVDC system.

Selection of Single Point Vulnerability through the Failure Mode Effect Analysis of Equipment in Newly built Nuclear Power Plant (신규원전의 기기별 고장분석을 통한 발전정지유발기기 선정)

  • Hyun, Jin-Woo;Yeom, Dong-Un;Song, Tae-Young
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.4
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    • pp.509-512
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    • 2012
  • For decreasing an unexpected shutdown of Nuclear Power Plants, Korea Hydro & Nuclear Power co.(KHNP) has developed Single Point Vulnerability(SPV) of NPPs since 2008. SPV is the equipment that cause reactor shutdown & turbine trip or more than 50% power rundown due to its malfunction. Newly built Nuclear Power Plants need to develop the SPV list, so performed the job which analyse equipment failure effect for SPV selection for 1 year. To develop this, Failure Mode Effect Analysis(FMEA) and Fault Tree Analysis(FTA) methods are used. As results of this analysis, about 900 equipment are selected as SPV. Thereafter those are going to be applied to Nuclear Power Plants to enhance equipment reliability.

The Effect of Thyristor Controlled Series Capacitor(TCSC) on Power Transfer Capability (TCSC 투입계통의 송전용량 증대에 대한 연구)

  • Lee, Joo-Ho;Lee, Byoug-Jun
    • Proceedings of the KIEE Conference
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    • 1998.07c
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    • pp.890-892
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    • 1998
  • TCSC is a FACTS device that can control the active power flow and current of transmission lines by adjusting line impedances. In this paper, we study the effect of TCSC on power transfer capability. A static model of TCSC is implemented in the continuation power-flow(CPF) Program and the power transfer capability is measured using the CPF. The site of TCSC is selected to increase power transfer capability by the sensitivity information provided from the CPF. The effect of TCSC with various control mode is tested in IEEE New England 30-bus system.

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Application of electric pulsed power on fruit body production of edible and medicinal mushrooms

  • Ohga, Shoji
    • Korean Journal of Agricultural Science
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    • v.39 no.4
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    • pp.591-594
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    • 2012
  • Effect of pulsed power was investigated on fruit body formation of 10 edible mushrooms, Lentinula edodes, Glifola frondosa, Pholiota nameko, Flammulina velutipes, Hypsizygus marmoreus, Pleurotus ostreatus, Pleurotus eryngii, Pleurotus abalonus, Agrocybe cylindracea and Sparassis crispa. Pulsed power of 100-170 kV was directly charged to the substrate just before fructification. The effect of the pulsed power resulted to promote for 10 edible mushrooms fructification. The treatment especially stimulated the fructification on Pleurotus species.

Power Absorption Measurements during NMR Experiments

  • Felix-Gonzalez, N.;Urbano-Bojorge, A.L.;de Pablo, C. Sanchez-L;Ferro-Llanos, V.;del Pozo-Guerrero, F.;Serrano-Olmedo, J.J.
    • Journal of Magnetics
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    • v.19 no.2
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    • pp.155-160
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    • 2014
  • The heating produced by the absorption of radiofrequency (RF) has been considered a secondary undesirable effect during MRI procedures. In this work, we have measured the power absorbed by distilled water, glycerol and egg-albumin during NMR and non-NMR experiments. The samples are dielectric and examples of different biological materials. The samples were irradiated using the same RF pulse sequence, whilst the magnetic field strength was the variable to be changed in the experiments. The measurements show a smooth increase of the thermal power as the magnetic field grows due to the magnetoresistive effect in the copper antenna, a coil around the probe, which is directly heating the sample. However, in the cases when the magnetic field was the adequate for the NMR to take place, some anomalies in the expected thermal powers were observed: the thermal power was higher in the cases of water and glycerol, and lower in the case of albumin. An ANOVA test demonstrated that the observed differences between the measured power and the expected power are significant.

The anti-inflammatory effect of low power GaAsAl laser stimulation on the polyarthritis of rats (다발성 관절염 실험동물 모델에서 저출력 GaAsAl 레이저 자극에 의한 소염효과)

  • Chang, Moon-Kyoung;Shim, Kyu-Rhee;Choi, Young-Deog
    • Journal of Korean Physical Therapy Science
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    • v.9 no.2
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    • pp.99-109
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    • 2002
  • We designed the experiments to elucidate the anti-inflammatory effect of low power laser stimulation on acupoint or non-acupoint using arthrogenic solution induced poly arthritis animal model. In order to achieve the experimental purpose, change in body weight paw edema, pathological changes in inflammed pint and the serum interlukin-6 level were measured after arthritis induction in acupoint later stimulated group, non acupoint laser stimulated group and non treated control animal. The results were summerized as follows: 1. The consistent increase in body weight was observed in the normal animal during whole experimental period, while the induction of arthritis significantly suppressed increase in body weight from the 15 day after arthritis induction. Especially, non treated animal group showed more suppressive effect on increase in body weight as compared to that of low power laser stimulated groups (P<0.05). 2. Low power laser stimulation on acupoint (Zusanli) significantly inhibited edema in the left side paw from the 12th day after arthritis induction as compared to that of non treated animals. This suppressive effect on paw edema was maintained until the end of experiment. 3. Laser treatment on acupoint dramatically suppressed the radiological change (i.e. new bone proliferation and soft tissue swelling) caused by arthritis as compared to that of non treated group animals. 4. Low power laser treatment reduced the increase in serum interlukin-6 caused by arthritis induction to levels observed in the normal animals. In conclusion, the results of the present study demonstrated that low power laser stimulation on acupoint has potent anti-inflammatory effect on arthritis. Thus it is recommended that low power laser be used for long term treatment of arthritis induced inflammation. However, further study is necessary to clarify the possible side effect of laser treatment depending upon intensity and duration of stimulation.

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The effect of low power GaAlAs laser stimulation on anti-nociception and spinal neuronal activity related to pain sensation in the polyarthritis of rats (다발성 관절염 실험동물 모델에서 저출력 GaAlAs 레이저 자극의 진통효능 및 통증관련 척수내 신경세포의 활성변화에 관한 연구)

  • Chang, Moon-Kyung;Choi, Young-Duk;Park, Bong-Soon
    • Journal of Korean Physical Therapy Science
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    • v.10 no.1
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    • pp.180-189
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    • 2003
  • The experiments were designated to evaluate the anti-nociceptive effect of low power laser stimulation on acupoint or non-acupoint using arthrogenic solution induced poly arthritis animal model. Evaluation of potential antinociceptive effect of low power laser on arthritis has employed measurements of the foot bending test, the development of either thermal or mechanical hyperalgesia following the arthritis induction. The analysis of thermal hyperalgesia includes Hargreaves's method. Randall-Sellitto test was utilized for evaluating mechanical hyperalgesia. In addition, the antinociceptive effect of low power laser stimulation on arthritis induced spinal Fos expression was analyzed using a computerized image analysis system. The results were summerized as follows: 1. In laser stimulation on acupoint treated animal, laser stimulation dramatically inhibited the development of pain in foot bending test as compared to those of non acupoint treated animal group and non treated animal group. 2. The threshold of thermal stimulation was significantly increased by low power laser stimulation on acupoint as compared to that of non treated control group. 3. Laser stimulation on acupoint dramatically attenuated the development of mechanical hyperalgesia as compared to that of non treated group. 4. Low power laser stimulation on acupoint significantly suppressed arthritis induced Fos expression in the lumbar spinal cord at 3 week post arthritis induction. In conclusion, the results of the present study demonstrated that low power laser stimulation on acupoint has potent anti-nociceptive effect on arthritis. Additional supporting data for an antinociceptive effect of laser stimulation was obtained using Fos immunohistochemical analysis on spinal cord section. Those data indicated that laser stimulation induced antinociception was mediated by suppression of spinal neuron activity in pain sensation.

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A Study on a Shielding Effect of the Messenger Wires in Distribution Lines (배전선로에서의 조가선 차폐 효과 연구)

  • Kim, In-Soo;Han, Woong;Yeo, Sang-Min;Kim, Chul-Hwan;Weon, Bong-Ju;Lim, Yong-Hun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.3
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    • pp.431-436
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    • 2009
  • As the telecommunication lines bring into widespread use, one of the most important aspects related to power distribution systems is effectively to evaluate the effect on the telecommunication lines from power lines. One of the efficient methods to evaluate the effect is to measure the induced voltage of a telecommunication line as a result of a ground-loop. If the power lines cause high induced voltage, the ground reference in the telecommunication lines is no longer a stable potential, so signals may ride on the noise. A ground loop is common wiring conditions where a ground current may take more than one path to return to the grounding electrode at the arrangement between the power lines and telecommunication lines. When a multi-path connection between the power lines and telecommunication line circuits exists, the resulting arrangement is known as a ground loop. Whenever a ground loop exists, there are potential for damages or abnormal operations of the telecommunication lines. The power lines can induce the voltage on the communication line. The effects can be calculated by considering the inductances and capacitances. However, if we assume that there are only power lines, it doesn't have a practical meaning because there are conductors with other purpose in the neighborhood of the lines. If we consider that case, we need more complex system. Therefore we suggest more complex system considering the conductors with other purpose in the neighborhood of the lines. The neutral wires and the overhead ground wires are considered for calculating the induced voltage. We assume that there are the messenger wires beside the power line as a result of increased use of them. The main purpose of this paper is a study on a shielding effect of messenger wires in the distribution lines. EMTP(Electro-Magnetic Transients Program) program is used for the induced voltage calculation.

The Effects of Power-of-Speech and Sex of Source on Persuasion, in Radio CM (라디오 광고에서 언어 힘의 설득 효과와 정보원 성(性)의 영향)

  • Chun, Hyun-Suk;Lyi, De-Ryoung
    • Journal of Global Scholars of Marketing Science
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    • v.16 no.1
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    • pp.93-116
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    • 2006
  • The main purpose of this study is to examine whether power-of-speech have an impact on persuasion in radio CM and to determine what is stronger variable either power-of-speech or sex of source. Previous research showed confused result about this issue. Some research supposed the effect of power-of-speech depend on sex of source/Carli, 1990) but the others supposed it is not(Holtgraves & Lasky, 1999; Erickson, Lind, Johnson, & O'Barr, 1978). So present research is designed to show empirical evidence about this issue examining the interaction between effect of power-of-speech and sex of source. Result revealed that power-of-speech affects strongly on persuasion and that effect have no interaction with sex of source. This result means that the effect of power-of-speech is stronger than the effect of sex of source. But in attitude toward product exceptionally, female source using powerful speech induce more favorable attitude toward product than female source using powerless speech whereas male source using powerful and powerless speech induce same attitude toward product.

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