• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.3
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• pp.8-14
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• 2018

PV module power is calculated on PV module surface temperature adjustment by irradiation on the summer and autumn in NOCT(Nominal Operating Cell Temperature) conditions. The summer and autumn periods were selected because of large variation in outdoor air temperature and irradiation. This study was performed to understand relationship between PV module surface temperature and photovoltaic power using field measurement. As a results, it was determined that the amount of irradiation was proportional to the amount of photovoltaic power in the field measurement. However, it was also identified that the PV power generation decreased by increased PV module surface temperatures due to irradiation.

• Proceedings of the KIEE Conference
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• 2004.07e
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• pp.68-71
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• 2004

Frequency is an important operating parameter of a power system. Electric power systems sustain transient frequency swings whenever the balance between generation and load does not no longer hold. To cope with this Constraints, it requires an accurate and high speedy frequency deviation estimation technique and suitable adjustment to obtain the power system energy balance. This paper describes the design, computational aspects and implementation of an iterative technique for measuring power system. The rate change of the phase angle is used for estimation. To confirm the validity of the proposed algorithm, the simulation studies carried out on a typical 154[KV] double T/L system by using EMTP software. Some test results are presented in the paper.

• Proceedings of the KIEE Conference
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• 2003.07e
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• pp.92-95
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• 2003

Frequency is an important operating parameter of a power system. Electric power systems sustain transient frequency swings whenever the balance between generation and load does not no longer hold. To cope with this Constraints. it requires an accurate and high speedy frequency deviation estimation technique and suitable adjustment to obtain the power system energy balance. This paper describes the design, computational aspects and implementation of an iterative technique for measuring power system. The rate change of the phase angle is used for estimation. To confirm the validity of the proposed algorithm, the simulation studies carried out on a typical 154[KV] double T/L system by using EMTP software. Some test results are presented in the paper.

• Proceedings of the KIEE Conference
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• 2005.10a
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• pp.145-149
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• 2005

Frequency is an important operating parameter of a power system. Electric power systems sustain transient frequency swings whenever the balance between generation and load does not no longer hold. To cope with this Constraints, it requires an accurate and high speedy frequency deviation estimation technique and suitable adjustment to obtain the power system energy balance. This paper describes the design, computational aspects and implementation of an iterative technique for measuring power system. The rate change of the phase angle is used for estimation. To confirm the validity of the proposed algorithm, the simulation studies carried out on a typical 154[KV] double T/L system by using EMTP software. Some test results are presented in the paper.

• Management & Information Systems Review
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• v.31 no.1
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• pp.89-116
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• 2012

This paper is an empirical study for the listed manufacturing companies in the Korea Stock Exchange during the sample period(2001-2010). The research is based on the target adjustment model(Shyam-Sunder and Myers(1999)) and the pecking order model(Frank and Goyal(2003)), and is aimed at reflecting the critical viewpoint of Chirinko and Singha(2000). An analysis in the model of Shyam-Sunder and Myers(1999) shows the value is too low to support the pecking order model in view of the following results. A target adjustment coefficient value is between 0 and 1, and is significant variable and explanatory power is very high, while deficit-in-funds coefficients close to 0. In addition, the result of an empirical test following the methodology used by Frank and Goyal(2003) does not support the pecking order theory.

• Quality Improvement in Health Care
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• v.10 no.2
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• pp.164-175
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• 2003

Objectives: To evaluate the performance of models to predict AMI patients death using severity adjustment measures in Korea. Methods: Medical records of 861 patients treated by AMI in 7 general hospitals during 1996 and 1997 were reviewed by trained nurses. We measured the severity of patients by APACHE III, MedisGroups, CSI and DS. Using each severity method a predictive mortality for each patient was calculated from a logistic regression model including the severity score. The statistical performance of each severity method model was evaluated by using c-statistics and R2. For each hospital, z scores compared actual and expected mortality rates. Results: The overall in-hospital mortality was 14.5%, ranged from 10.0% to 22.2%. The distributions of severity scores for each method was significantly different by hospitals. The four severity-adjusted models to predict AMI patients death varied in their statistical performance for discrimination power of patients death. Order of Severity-adjusted mortality rates and z scores by four severity measures was different. Conclusion: Severity-adjusted mortality rates of AMI patients might be applied as an indicator for hospital performance evaluation in Korea. Because different severity methods frequently produce different impressions about relative hospital performance, more studies has to be done to use it as quality indicator and more attention should be paid to select appropriate severity measures.

• Korean Journal of Social Welfare
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• v.52
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• pp.143-170
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• 2003

This study investigated the effectiveness of the assessment of psychosocial treatment outcome in symptomatology and social functioning as rated by the depressed client's significant other in explaining the client's symptomatology and social adjustment at 6 and 12 month follow-up period after the 16-week psychosocial treatment was terminated. The data were drawn from the National Institute of Mental Health Treatment of Depression Collaborative Research Program of the U.S. Significant others of depressed clients have rarely participated in the assessment of treatment outcome, although they are major participants of the clients' daily life and have meaningful opportunities to observe the clients' functioning in different social situations. Thus, this study aimed to examine the explanatory power of the significant others' outcome assessment in depressive symptomatology and social functioning for the long-term outcome in symptomatology and social adjustment. The outcome measures used by the significant others were actual performance, expected performance, gap between actual and expected performance, and symptomatology drawn from the Katz Adjustment Scale-Relatives Form. Three major findings were: (1) in general, the posttreatment assessment by the significant other demonstrated stronger explanatory power of the follow-up status than the assessment rated at pretreatment in all of the four outcome domains; (2) the significant other's assessment of actual and expected performance at both pre- and posttreatment demonstrated significant explanatory power of the follow-up status in symptomatology and social/leisure and work adjustment; and (3) the significant other's assessment of social functioning at pretreatment improved the explanatory power over and above the explanation by symptomatology in the follow-up status of social/leisure and work adjustment; however, at posttreatment, symptomatology improved the explanation over and above social functioning more frequently in predicting both symptomatology and social/leisure and work adjustment. These findings suggest the effectiveness of the measures of symptomatology and actual and expected performance as assessed by significant others. The results imply that mental health professionals and researchers need to involve the depressed client's significant other in the treatment and make good use of their contribution in treatment planning and further intervention in the follow-up period to prevent relapse.

• Tribology and Lubricants
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• v.25 no.5
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• pp.311-317
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• 2009

To satisfy the more severe emission regulation and the demand of higher fuel economy in near future, the combustion pressure and power output of engines is going to be higher. In order to get the reduction of engine emission and the higher power, it is needed the reduction of the tension and width of ring pack. The lower tension ring and the thinner width ring can bring not only the friction reduction between the ring and liner during engine running, but also the adjustment of the blow-by gas and oil consumption by changing in the pressure in the crevice volume and the axial motion of rings togethe with the adjustment of the inter-ring crevice volumes. In this study, by using a developed basic computer proglram that predicts the blow-by gas and oil consumption of engines, it is to be examined how satisfying the level of the blow-by gas and oil consumption as being installed the piston ring pack with thinner width ring and lower tension ring.

• Journal of Families and Better Life
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• v.9 no.2
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• pp.345-366
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• 1991

The concrete purpose of this study is to examine the possibility of applying S.Minuchin's structural family therapy theory to each clinical families so that it can solve efficiently the clinical problems Korean family. The test results are as follows: 1)The Results of Question I : Types of Korean family problems can be divide into six. Then the most frequent type of problem was marital problem. 2) The Results of Question II: Korean normal family showed rater difussed boundary and higher rate of wife dominant type than that of husband dominant type in aspect of boundary and power, and had low tendency toward alignment and neutral adjustment. 3)The Results of Quesion III; Amidst the clinical families, family structural traits of the families which have marital problems showed a clear boundary, the tendency toward alignment, and higher tate of husband dominant type than that of wife dominant type. And family structural traits of children problem family had the tendency of alignment and showed little wife-dominanted families in power. Finally, mother-in -law and daughter-in-law problemed family had several characters such as diffused boundary, the tendency of alignment and high adjustment. 4)The Results of Question IV : As a result of camparing problemed families with normal families in family structure, there was high adaptability of S.Minuchin's structural theory to the two family groups; the groups of marital problems and those of children problem.

• Journal of Power Electronics
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• v.16 no.3
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• pp.946-959
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• 2016

A novel Virtual Space Vector (VSV) modulation strategy for complete control of potential neutral point (NP) issues is proposed in this paper. The neutral point potential balancing problems of multi-level converters, which include elimination of low frequency oscillations and self-balancing for NP dc unbalance, are investigated first. Then a set of improved virtual space vectors with dynamic adjustment factors are introduced and a multi-objective optimization algorithm which aims to optimize these adjustment factors is presented in this paper. The improved virtual space vectors and the multi-objective optimization algorithm constitute the novel Virtual Space Vector modulation. The proposed novel Virtual Space Vector modulation can simultaneously recover NP dc unbalance and eliminate low frequency oscillations of the neutral point. Experiment results show that the proposed strategy has excellent performance, and that both of the neutral point potential issues can be solved.