• Proceedings of the KIEE Conference
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• 1997.07f
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• pp.2095-2097
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• 1997

This paper describes a indirect sensing method for the rotor flux position of interior permanent magnet (IPM) brushless DC motors. The phase inductance of an IPM motor varies appreciably according to the rotor position. The waveform characteristics of the terminal voltage of IPM brushless DC motors is analysed and a simple and practical method for indirect sensing of the rotor position is proposed. A compact sensorless drive is implemented and tested using a 87c196mc 16-bit microcomputer. The experimental results show the validity of the proposed method and the drive works well from 500 to 7,200rpm.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.591-595
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• 2000

In this paper we proposed a new sensorless drive system for the trapezoidal type brushless DC motor which does not use any mechanical position or speed sensor and applicable to the systems requiring a constant speed and torque such as Fan. For this a novel indirect rotor position sensing technique based on a detailed analysis of the terminal voltage characteristics is proposed in this paper. And a sensorless drive system for the brushless DC motor is implemented using a 87c196mc fo the main microprocessor and a power FET for the inverter. The experimental results will show the validity of the proposed indirect sensing method and the practical use of the sensorless drive

• Horticultural Science & Technology
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• v.18 no.6
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• pp.811-814
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• 2000

Effects of kanamycin concentration on regeneration and rooting of transgenic 'McIntosh Wijcik' were investigated to establish the efficient Agrobacterium-mediated transformation system. Relatively high regeneration frequency of explants appeared even at the high concentration of $150mg{\cdot}L^{-1}$ kanamycin, but the regeneration frequency and the number of normal shoots decreased significantly at a concentration of higher than $100mg{\cdot}L^{-1}$ kanamycin in the gelrite-gellifying medium. Rooting response varied with the transgenic lines in the agar-solidifying medium supplemented with the different concentrations of kanamycin and they were grouped with the inhibition level at $30mg{\cdot}L^{-1}$ concentration. No correlation between copy number and root response was observed. The optimum concentrations of kanamycin for the regeneration of 'McIntosh Wijcik' apple in the medium gellified with gelrite and for indirect-selection of putative transformants in the rooting medium solidified with agar were found to be $100mg{\cdot}L^{-1}$ and $30mg{\cdot}L^{-1}$ respectively.

• Journal of Korean Academy of Nursing
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• v.40 no.1
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• pp.127-138
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• 2010

Purpose: This study was designed to develop and test a structural model for children's adaptation in divorced families. The hypothetical model was constructed based on the Family Resilience Model by McCubbin and McCubbin. Methods: Data were collected using self-report questionnaires from 219 children (3-6th grade) in divorced families. The children attended one of 22 community agencies, 8 after-school programs, 3 elementary schools in three cities in South Korea. The collected data were analyzed using LISREL program to test the hypothetical model. Results: The modified model was constructed by deleting four paths in accordance with the statistical and theoretical criteria. Compared to the hypothetical model, the revised one had a better fit to the data. Self-esteem, and beliefs about parental divorce had direct effects, and family communication and internal control had indirect effects on children's adaptation in divorced families. These variables explained 56% of the variance in children's adaptation. Conclusion: The modified model was supported by empirical data. This model could be applied to family nursing interventions with divorced families or any other suffering family transition. When working with children experiencing parental divorce, it is important for nurses to enhance children's self-esteem, family communication and to decrease children's negative beliefs about parental divorce to help in their adaptation.

• The Transactions of the Korean Institute of Power Electronics
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• v.6 no.3
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• pp.223-230
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• 2001

This power proposes a new sensorless drive system for the trapezoidal brushless DC motor generally requiring mechanical position or speed sensor. For this an indirect rotor position sensing method from the back emf waveform of non-conducting phase is explained. Back emf waveform of non-conducting is obtained from analysing terminal voltage created by making Y-connection. And an experiment is implemented with a driving system which use 87c196mc microcontroller having a peripheral associated with 3-phase signals and inverter composed of Power MOSFET. The experimental results show the validity and practicality of the proposed sensorless drive.

• BMB Reports
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• v.47 no.10
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• pp.587-592
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• 2014

We investigated the effects of ${\beta}$-adrenergic activation on bone marrow adiposity and on adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). C57BL/6 mice were subjected to a control (CON), high calorie (HIGH) or low calorie (LOW) diet for 12 weeks. In each group, mice were treated with vehicle (VEH) or propranolol. The number of adipocytes per area bone marrow was increased in LOWVEH and HIGHVEH mice compared with CONVEH mice, which was attenuated by propranolol. Isoproterenol increased lipid droplet accumulation and adipogenic marker gene expression in 3T3-L1 preadipocytes and mouse BMSCs, which were blocked by propranolol. Conditioned medium obtained from MC3T3-E1 osteoblasts suppressed adipogenic differentiation of 3T3-L1 cells, which was significantly attenuated by treatment of MC3T3-E1 cells with isoproterenol. These data suggest that ${\beta}$-adrenergic activation enhances bone marrow adipogenesis via direct stimulation of BMSCs adipogenesis and indirect inhibition of osteoblast anti-adipogenic potential.

• Child Health Nursing Research
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• v.18 no.4
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• pp.222-230
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• 2012

Purpose: The purpose of this study was to identify the effect of family stressors, family strains, general family values, family values for hospitalized children and family hardiness on family adaptation based upon McCubbin's family resilience model for families of hospitalized children in China. Methods: A survey using a self-report questionnaire was conducted with 330 hospitalized children's parents. Six instruments were used in this model. The data were analyzed using SPSS WIN 19.0 and AMOS 19.0 program. Results: Family strain had a significant negative direct effect, general family values and family hardiness had a significant positive direct effect, and family values for hospitalized children had a significant positive direct effect and indirect effect on family adaptation of hospitalized children. Conclusion: In this study McCubbin's resilience model and resiliency factors were identified. According to the finding of this study nursing interventions to reduce family stress, enhance family hardiness and consolidate general family values and family values for hospitalized children can help to increase family adaptation in families of hospitalized children. Therefore, the significance of this study is that the results can be used to develop family nursing intervention programs based on family resilience to strengthen family adaptation in families of hospitalized children.

• Child Health Nursing Research
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• v.10 no.4
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• pp.383-394
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• 2004

Purpose: This study was conducted to identify resiliency factor, to test causal relationship and effect of resiliency factors on adaptation in families of children with cancer. A conceptual framework was constructed based on McCubbin's resiliency model. Hypotheses were tested with empirical data. Method: Data were collected using self-report questionnaire from 232 families of children with cancer. The collected data were analyzed using the SAS program and LISREL program for covariance structural analysis. Result: Family hardiness and problem-solving coping had significant direct effects on adaptation in families of children with cancer. Social support had significant indirect and total effect on adaptation. Family Schema had significant direct effect on family hardiness and problem-solving coping. Problem-solving communication had a significant direct effect on family hardiness and an indirect effect on family functioning and problem-solving coping. Among the resiliency factors, family hardiness had the greatest effect on adaptation in family of children with cancer. Conclusion: The findings suggest that nursing interventions to enhance family hardiness, problem-solving coping and social support would result in an increase in adaptation in families of children with cancer. An integrated intervention that emphasizes and promotes resiliency factors should be developed and established for families of children with cancer.

• Journal of Power Electronics
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• v.19 no.6
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• pp.1380-1392
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• 2019

Input filters are very important to matrix converters (MCs). They are used to improve grid side current waveform quality and to reduce the input voltage distortion supplied to the grid side. Due to the effects of the input filter and the output power, the grid side power factor (PF) is not at unity when the input power factor angle is zero. In this paper, the displacement angle between the grid side phase current and the phase voltage affected by the input filter parameters and output power is analyzed. Based on this, a new grid side PF unity compensation method implemented in the indirect space vector pulse width modulation (ISVPWM) method is presented, which has a larger compensation angle than the traditional compensation method, showing a higher grid side PF at unity in a wide output power range. Simulation and experimental results verify that the analysis of the displacement angle between the grid side phase current and the phase voltage affected by the input filter and output power is right and that the proposed compensation method has a better grid side PF at unity.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1624-1633
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• 2009

Brake system in railway train operates to reduce the speed of the train or to stop the train via changing the kinematic energy into heat energy for emission and so brake system makes an important rule to transport passenger and cargo for safety operation. Recently operators have a matter of grave concern for the verification of performance in brake system. To verify the exact performance of brake system, most of brake test has been carried out on real operating track condition. Therefore we will determine the braked weight of indirect brake system applied in Iran DMU(Diesel Multiple Unit) in accordance with mc leaflet 544-1, which is to enable Iran DMU to achieve the required braking distances in defined situation.