• Title/Summary/Keyword: Power Adjustment

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Characteristics of Sparkover Discharge in Flowing Air with Reynolds Number's Variable (Reynolds Number를 변수로한 유동공기의 방전특성에 관한 연구)

  • 김영훈;이동인;이광식;김상구
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 1990.10a
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    • pp.41-46
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    • 1990
  • This paper shows the characteristics of sparkover discharge in flowing air ranging from O(Reynolds number, Re to 10.52$\times$104(Re). Also, we investigated changes of dis-charge pattern for constant input power by adjustment of the Re. The important results obtained from this paper are as followers. The maxinum sparkover voltage of flowing air are about 6.3[kV] higher than those of static air. The discharge pattern can be controlled by adjustment of the Re.

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Chi-squared Tests for Homogeneity based on Complex Sample Survey Data Subject to Misclassification Error

  • Heo, Sunyeong
    • Communications for Statistical Applications and Methods
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    • v.9 no.3
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    • pp.853-864
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    • 2002
  • In the analysis of categorical data subject to misclassification errors, the observed cell proportions are adjusted by a misclassification probabilities and estimates of variances are adjusted accordingly. In this case, it is important to determine the extent to which misclassification probabilities are homogeneous within a population. This paper considers methods to evaluate the power of chi-squared tests for homogeneity with complex survey data subject to misclassification errors. Two cases are considered: adjustment with homogeneous misclassification probabilities; adjustment with heterogeneous misclassification probabilities. To estimate misclassification probabilities, logistic regression method is considered.

Binary Nonlinear Joint Transform Correlator with Sinusoidal Iterative Filter in Spectrum Domain

  • Jeong, Man-Ho
    • Journal of the Optical Society of Korea
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    • v.14 no.4
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    • pp.357-362
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    • 2010
  • The joint transform correlator (JTC) has been the best known technique for pattern recognition and identification. This paper proposes a new technique of fringe adjustment by adopting a sinusoidal amplitude-modulated iterative filter convolved with an interference fringe pattern in the joint power spectrum (JPS) domain. The comparison of our new technique and other techniques is presented to show that the newly proposed technique can successfully improve both the correlation peaks and the peak signal-to-noise ratio (PSNR). Simulated results of enhanced interference fringes are also presented.

Influence of Trauma Experiences and Social Adjustment on Health-related Quality of Life in North Korean Defectors (북한이탈주민의 외상경험과 사회적응이 건강 관련 삶의 질에 미치는 영향)

  • Jo, Eun Joo;Cho, Hyun Mee;Choi, Eun Joung
    • Research in Community and Public Health Nursing
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    • v.29 no.4
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    • pp.488-498
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    • 2018
  • Purpose: This study was conducted to identify the influence of trauma experiences and social adjustment on health-related quality of life in North Korean defectors. Methods: The subjects were 117 North Korean defectors living in B and Y city. The data were collected from September 1 to September 20, 2014, and analyzed by the SPSS/WIN 18.0 program. Results: Significant differences were found in the health-related quality of life with respect to the subjects' education, marriage status, types of dwelling, family types, duration of residence in South Korea, jobs in South Korea and in North Korea, families left in North Korea or other surrounding countries, and subjective health status. Health-related quality of life is negatively related to trauma experiences during escape from North Korea and during their life in South Korea. Health-related quality of life positively is related to social adjustment. The meaningful variables which influenced the subjects'health-related quality include social adjustment, job in South Korea, job in North Korea, current family structure, and trauma experiences in South Korea. Total explanatory power of these factors for health-related quality in North Korean Defectors is 43.0% and social adjustment is the most influential factor. Conclusion: Therefore, in order to enhance health-related quality of life in North Korean defectors, it is necessary for them to increase social adjustment and decrease trauma experiences. In addition, methods are needed to provide job opportunities, better education and family services for North Korean defectors.

The Effect of Self-Awareness and Other-Awareness on College Life adjustment in Dental Hygiene Students (일부 치위생과 학생의 자기인식 및 타인인식이 대학생활 적응에 미치는 영향)

  • Ji-Young Lee
    • Journal of Korean Dental Hygiene Science
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    • v.6 no.2
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    • pp.161-172
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    • 2023
  • Background: The purpose of this study is to assess the degree of self-awareness, recognition of others, and adaptation to college life of dental hygiene students, and to identify the factors affecting college life adjustment. Methods: The effect size was calculated using the G*power 3.1.9.4 program, based on the data of 191 people who agreed to participate in the questionnaire. Independent samples t-test, one way ANOVA, Post HOC Scheffe, correlation analysis, and multiple regression analysis were conducted to explore the difference and correlation between self-awareness, perception of others, and college life adjustment according to general characteristics. Results: A significant positive correlation was found in self-awareness (r=.301). The highest positive correlations were with social adjustment in both private (r=.340) and public self-awareness (r=.331) (p<0.01). Recognition of others (r=-.051) showed a negative correlation with college life adjustment, though it was not statistically significant. As factors for adapting to college life, private self-awareness (β=.232) and public self-awareness (β=.254) had a positive (+) effect, and internal self-awareness (β=-.205) was found to have a negative (-) effect (p<0.01) Conclusion: The self-awareness and recognition of others among dental hygiene students influence their smooth adjustment to college life. Improvement measures are recommended to enhance adaptability to college life and develop core competencies related to their major

Fuzzy-PWM control for adjustment of power rate of a multiple point temperature controller (다점 온도 제어 장치의 power 공급율 조정을 위한 fuzzy-PWM제어)

  • 이장명;윤종보
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.34S no.11
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    • pp.80-92
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    • 1997
  • This research focuses onan efficient control method of temperature for multiple points using only one processor. For a yarn production system, the surface temperature control of heaters are very important for quality control. Therefore, we designed a temperature controller for a draw and twist machine and applied Fuzzy-PWM algorithm to the controller. If we use a processor for the temperature control of multiple points with the conventional ON/OFF control, the control performance of the system becomes poor. To overcome these problems, we developed a new Fuzzy-PWM algorithm for the adjustment of power rate to the heaters in the conventional ON/OFF control. It is shown that this algorithm has the same effects as the PID algorithm for the temperature control of each point. The proposed algorithm is robust against the production condition and environment such as the reference temperature and the thickness of yarn, since the power rate to the heater is adjusted by Fuzzy Rules derived from the values of the reference termperatureand the thickness of yarn. To obtain optimal Fuzzy rulees, the control simulations are perfodrmed through the modelling of the heater and simulation of Fuzzy rules. This algorithm is applied for the multiple pont temperature controller and showed satisfactory performance.

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The Weldability of Laminated Stator Core for Motor by Pulsed Nd:YAG Laser [ I ] - The Effect of Processing Parameter on Weldability of Laser - (펄스 Nd:YAG 레이저를 이용한 모터용 스테이터 적층코어의 용접특성 [ I ] - 레이저 용접성에 미치는 가공변수의 영향 -)

  • Kim Jong-Do;Yoo Seung-Jo;Kim Jang-Soo
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.5
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    • pp.629-635
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    • 2006
  • Manufacture of motor by laser has been studying realization that was demands on market for lightening and miniaturization. Moreover. early in the 1980s. manufacture of parts for automobiles by laser welding was already successfully introduced. The purpose of this study was to develop production technology of the high quality laminated stator core for motor by pulsed Nd:YAG laser heat source. In the event of adjusting defocus and voltage to control humping in laser welding of the laminated core. sound bead could be obtained. but deep penetration was not. Therefore. explosive evaporating plasma was controlled by adjustment of peak power on pulse width. Particularly, because explosive evaporating plasma induced high peak power, made molten metal in keyhole scatter. a suitable adjustment of peak power was required to obtain sound bead. As a results of experiment. sound bead and deep penetration could be obtained.

Sensorless Scheme for Interior Permanent Magnet Synchronous Motors with a Wide Speed Control Range

  • Hong, Chan-Hee;Lee, Ju;Lee, Dong-Myung
    • Journal of Power Electronics
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    • v.16 no.6
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    • pp.2173-2181
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    • 2016
  • Permanent magnet synchronous motors (PMSMs) have higher torque and superior output power per volume than other types of AC motors. They are commonly used for applications that require a large output power and a wide range of speed. For precise control of PMSMs, knowing the accurate position of the rotor is essential, and normally position sensors such as a resolver or an encoder are employed. On the other hand, the position sensors make the driving system expensive and unstable if the attached sensor malfunctions. Therefore, sensorless algorithms are widely researched nowadays, to reduce the cost and cope with sensor failure. This paper proposes a sensorless algorithm that can be applied to a wide range of speed. The proposed method features a robust operation at low-speed as well as high-speed ranges by employing a gain adjustment scheme and intermittent voltage pulse injection method. In the proposed scheme the position estimation gain is tuned by a closed loop manner to have stable operation in tough driving environment. The proposed algorithm is fully verified by various experiments done with a 1 kW outer rotor-type PMSM.

Design Procedure of Robust LQG/LTR Controller of TCSC for Damping Power System Oscillations (전력시스템 동요 억제를 위한 TCSC의 강인한 LQG/LTR 제어기 설계절차에 관한 연구)

  • Son, Kwang-Myoung;Lee, Tae-Gee;Jeon, In-Su
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.16 no.6
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    • pp.30-39
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    • 2002
  • This paper deals with the design of a robust LQC/LTR (Linear Quadratic Gaussian with Loop Transfer Recovery) controller of the TCSC for the power system oscillation damping enhancement. Designing LQG/LTR controller involves several design parameter adjustment processes for performance improvement. this paper proposes a systematic design parameter adjustment procedure which is suitable for robust multi-monde stabilization. The designed controller is verified by nonlinear power system simulation, which shows that the controller is effective for damping power system oscillations.

The High-frequency Induction-heating application for 2700kW power (2700kW급 고주파 유도 가열 장치의 시작)

  • 이영호;김용환;이광수;이현우
    • Proceedings of the KIPE Conference
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    • 1998.07a
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    • pp.171-174
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    • 1998
  • The development of the high-frequency induction-heating for 2700kW power range intend to make localization at forging and rolling mill part by technical innovation. And, the development makes to increase our's competitive power at technique, quality and cost. This paper describes the heart of high-frequency induction-heating technique, switching technique, a few problem in common using as an unsatisfied technique, load adjustment technique, system control, diagnostic system, and auto-interface etc.

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