• Title/Summary/Keyword: variable power factor

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A Study on Sex Role Identity and Makeup Behavior (여대생(女大生)의 성역할(性役割) 정체감(正體感)과 화장(化粧) 행동(行動)에 관(關)한 연구(硏究))

  • Kuh, Ja-Myung;Lee, Kwuy-Young
    • Journal of Fashion Business
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    • v.6 no.2
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    • pp.124-136
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    • 2002
  • This objective study were to classify the contents of makeup behavior, to investigate the relationship between makeup behavior and sex role identity, and to examine how the makeup behavior, makeup satisfaction was influenced by sex role identity and demographics. To achieve this, the researchers surveyed 162 women for the ages of 18 through 25. The result of this study are followed. 1) Four factor of makeup behavior were sexual attractiveness, aesthetic, psychological dependence and makeup interest. 2) There were significant positive relationship between makeup behavior and sex role identity. 3) Sexual attractiveness were influenced by femininity, income. The explanatory power of the 2 variables were 8.5%. Aesthetic were influenced by masculinity. The explanatory power of the 1 variable was 9.2%. Psychological dependence were influenced by femininity. The explanatory power of the 1 variable was 8.2%. Makeup interest were influenced by masculinity, age. The explanatory power of the 2 variables were 9.0%. 4 Makeup satisfaction were influenced by sexual attractiveness, aesthetic. The explanatory power of the 2 variables were 22.1%.

Development of a Simplified Statistical Methodology for Nuclear Fuel Rod Internal Pressure Calculation

  • Kim, Kyu-Tae;Kim, Oh-Hwan
    • Nuclear Engineering and Technology
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    • v.31 no.3
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    • pp.257-266
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    • 1999
  • A simplified statistical methodology is developed in order to both reduce over-conservatism of deterministic methodologies employed for PWR fuel rod internal pressure (RIP) calculation and simplify the complicated calculation procedure of the widely used statistical methodology which employs the response surface method and Monte Carlo simulation. The simplified statistical methodology employs the system moment method with a deterministic approach in determining the maximum variance of RIP The maximum RIP variance is determined with the square sum of each maximum value of a mean RIP value times a RIP sensitivity factor for all input variables considered. This approach makes this simplified statistical methodology much more efficient in the routine reload core design analysis since it eliminates the numerous calculations required for the power history-dependent RIP variance determination. This simplified statistical methodology is shown to be more conservative in generating RIP distribution than the widely used statistical methodology. Comparison of the significances of each input variable to RIP indicates that fission gas release model is the most significant input variable.

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Performance Analysis of the Rubber Belt type CVT System (고무 벨트식 무단변속기 시스템의 성능분석)

  • Kim, Sung-Mo;Zheng, Chun-Hua;Lim, Won-Sik;Cha, Suk-Won
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.20 no.4
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    • pp.376-381
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    • 2011
  • CVT(Continuously Variable Transmission) is one of the most promising candidates for the future automobile transmission because of its continuously variable gear ratio and reduced shift shock. It is also possible to operate the power source at its high efficiency region with CVT. The CVT system consists of thrust plate, driving pulley, belt, driven pulley, and preload spring of output shaft. In this paper, the dynamic modeling of a CVT system is completed to obtain the static performances of CVT system. A simulator is implemented on Matlab(Simulink), which can analyse the static performances of a CVT system. The methods for improving the total efficiency of a motorcycle system are also proposed based on the simulation results. In this study we increase the capacity factor of CVT up to the three times of default specification.

Analysis of Steady State Characteristics of Doubly-Fed Induction Generator in Wind Turbine system (이중여자 유도발전 풍력시스템의 정상상태 특성 해석)

  • Jang, Bo-Kyoung;Ro, Kyoung-Soo
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.460_461
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    • 2009
  • This paper analyzes the steady state characteristics for variable speed wind power system with doubly-fed induction generator(DFIG). This paper explains the equivalent circuit and phasor diagram of DFIG for different operating conditions. It also simulates the torque-slip characteristics with respect to changes of different parameters. Simulation results show the torque-slip characteristics, stator power factor-rotor voltage and stator current-rotor voltage.

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The Effects of Decision-Making Power of the Elderly to Home Management on the Life Satisfaction (가정경영에 대한 노인의 의사결정관이 생활만족도에 미치는 영향)

  • 문숙재
    • Journal of Families and Better Life
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    • v.11 no.1
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    • pp.203-217
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    • 1993
  • The purpose of this study was to investigate relations of decision-making power of the elderly to home management and life satisfaction by applying a social behavior theory and exchange theory and to find out the device which improve the elderly life satisfaction at the home management view. For these research tasks the data was collected through the questionaire and interview those respondents were 273 woman elderly living with one of their married children in Seoul. It was analyzed by various statistical methods such as Frequency Percentile ANOVA F-test t-test Pearson's Corrdlation Analysis Multiple Regression Analysis. The results of this study are as follows: 1) Decision-making power of the elderly to home management had significant differences according to all of th variables except for religion job status of the elderly and education income of the children. 2) Decision-making power of the elderly to home management had the significant differences according to the variable such as income of the elderly solidarity between the elderly and their adult children age of the elderly The most influencial factor was income of the elderly. 3) Elderly life satisfaction had significant differenced according to all of the variables except for age job status of the elderly and education income of the children inmate children 4) In the result of analyzing the elderly life satisfaction the most influencial factor was decision-making power to home management and the explanary power to home management and the explanary power of those variables for the elderly life satisfaction was 56.2%.

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Sensorless Control of 3-phase PFC AC/DC Converter using Kalman Filter (칼만필터를 이용한 3상 PFC AC/DC 컨버터의 센서리스 제어)

  • Park, Jun-Sung;Kwon, Young-Ahn
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.5
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    • pp.998-1004
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    • 2016
  • This paper investigates a new sensorless control appling a virtual flux oriented vector control without the line voltage sensor for the power factor correction of 3 phase PWM converter. The DC output voltage is controlled by applying the kalman filter algorithm for the virtual flux estimation and the synchronous phase is obtained by using the estimated virtual flux equation based on kalman filter. This method is used to reduce the calculation time of the system and obtain a stable control that the input current including the harmonics and the noise is improved. The proposed system implement PFC algorithm in the variable region of DC output voltage. It can obtain the unity power factor, and can precisely control the DC output voltage in the load variation and in the variable voltage range. The performance of the proposed algorithm is verified through simulation and experiment.

A Modular Bi-Directional Power Electronic Transformer

  • Gao, Zhigang;Fan, Hui
    • Journal of Power Electronics
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    • v.16 no.2
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    • pp.399-413
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    • 2016
  • This paper presents a topology for a modular power electronic transformer (PET) and a control scheme. The proposed PET consists of a cascaded H-Bridge rectifier on the primary side, a high-frequency DC/DC conversion cell in the center, and a cascaded H-Bridge inverter on the secondary side. It is practical to use PETs in power systems to reduce the cost, weight and size. A detailed analysis of the structure is carried out by using equivalent circuit. An algorithm to control the voltages of each capacitor and to maintain the power flow in the PET is established. The merits are analyzed and verified in theory, including the bi-directional power flow, variable voltage/frequency and high power factor on the primary side. The experimental results validated the propose structure and algorithm.

Limited Cost-Based Competition and the Cost Distortion Factor - How Real Variable Costs are Reported in Cost-Base Pool of Korean Power Market - (원가기반 제한경쟁과 비용왜곡 요인 -변동비 반영 전력시장에서의 실제변동비 반영사례를 중심으로-)

  • Kim, Myung-Seok;Cho, Sung Bong
    • Environmental and Resource Economics Review
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    • v.23 no.3
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    • pp.497-513
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    • 2014
  • Rate-of-return regulation where a regulator compensates the utilities based upon the cost incurred the regulated companies have the incentive to over-report cost level. However, in case of cost-based competition where a regulator knows the cost of each plant involved and induce the competition among them, one can encounter prisoner's dilemma situation in the short run where the regulated firms under-report cost level. For instance, in case of cost-based pool, a generator may have a strategic behavior to keep its registered variable cost higher than the actual level to maintain its operation rate and generation amounts higher. Eventually, however, such behavior decrease the profitability of a generator and discourage new entry jeopardizing required level of capacity reserves. This is a typical Prisoner's Dilemma situation. The power market operating rule should be revised so that generators' registered variable cost reflect actual level of variable cost.

Analysis of Design Factors for High Performance Fuzzy Logic Control of Refrigeration Cycle (냉동사이클의 고성능 퍼지제어를 위한 설계 인자들의 영향 분석)

  • Choi, Sung-Woon;Jeong, Seok-Kwon;Yang, Joo-Ho
    • Journal of Power System Engineering
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    • v.20 no.6
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    • pp.11-19
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    • 2016
  • A variable speed refrigeration system(VSRS) has been received high attention for energy saving ability. This paper investigates effects of design factors such as membership function range and sampling time to control performances for systematical designing fuzzy logic controller of the VSRS. Some comparisons of control performance between the fuzzy and PI are conducted including comparative evaluation of robustness against noise by using computer simulations. The simulation results showed that the fuzzy is very useful design method for engineers in the industrial fields which have big noises system and deal with inherent nonlinear system like the VSRS.

Driving Algorithm on Three Phase BLDC Motor Applied 4-Switch using Voltage Doubler (Voltage Doubler를 이용한 4-스위치 3상 BLDC 전동기 구동 알고리즘)

  • Yoon, Yong-Ho;Lee, Jung-Suk;Won, Chung-Yuen
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.60 no.1
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    • pp.48-52
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    • 2011
  • Over the years, traditionally, six-switch three-phase inverters have been widely utilized for variable speed alternating current motor drives. Recently, some efforts have been made on the application of four-switch three phase inverter for uninterruptible power supply and variable speed drives. This is due to some advantages of the four-switch three phase inverter over the conventional six-switch three-phase inverters such as reduced price due to reduction in number of switches, reduced switching losses, reduced number of interface circuits to supply logic signals for the switches, simpler control algorithms to generate logic signals, less chances of destroying the switches due to lesser interaction among switches, and less real-time computational burden. However such as slow di/dt and speed limitation, are the inherent characteristics and main drawbacks of the four-switch configuration. Those problems can be overcome in conjugation with Voltage-doublers which has additional advantage, such as unity power factor correction.