• International Journal of Quality Innovation
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• 제8권3호
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• pp.1-10
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• 2007

A sample of Italian manufacturing companies was selected in order to verify the abilities and effects (relationships) of the management factors human resources, leadership and strategic planning on company performance. The Partial Least Squares (PLS) estimation method was used for analyzing the data collected, where the relationships between the management factors and performance were formalized by a Structural Equation Model (SEM). The analysis of the survey data showed unexpected result regarding the non significant direct relationship between Leadership and Performance. The effect of Leadership is obtained by an indirect relationship through Human Resources. The combination of Leadership and Human Resources has hence been identified as the management factors which have the highest impact on the performance of Italian industrial companies. Another interesting and unexpected result was that there was no significant impact of Strategic Planning on Performance. It seems that the leaders of Italian industrial companies have not understood that good strategic planning is a necessary condition for achieving excellence. So another improvement area is in fact Strategic Planning. This area should have the highest priority of any top management team and the focus should include how to establish a strong relationship between strategic planning and performance. No correlation between strategic planning and performance is a strong indication that something is wrong. It is not enough that Leadership is doing Strategic Planning-Leadership is also about studying and follow up on results in order to assure impacts on performance. This link seems to be missing in Italian industrial companies.

• 한국생활과학회지
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• 제23권2호
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• pp.269-279
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• 2014

The purpose of this study was to examine the relationship between family violence exposure and school violence, to explore the mediating effects of family life satisfaction, school life satisfaction, and internalizing on those relationship and to suggest practical implications for social work services for those adolescents. 4,773 adolescents were selected for the questionnaire study in Gjwangju. Collected data were analysed by Structural Equation Modeling in AMOS 20.0 and SPSS 20.0. The findings of this study were as follows: First, there were significant correlations among family life satisfaction, school life satisfaction, internalizing and school violence offense with family violence exposure. Second, the structural model analysis revealed that family violence had no direct link with school violence. Third, Family violence had indirect effects on school violence, mediated by family life satisfaction, school life satisfaction and internalizing. Based on these findings, the research discussion reinforced the importance of family focused services to prevent the school violence and suggested effective intervention plan.

• The Korean Journal of Physiology and Pharmacology
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• 제6권4호
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• pp.187-191
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• 2002

Tamoxifen, an antiestrogen, has previously been shown to induce apoptosis in HepG2 human hepatoblastoma cells through activation of the pathways independent of estrogen receptors, i.e., intracellular $Ca^{2+}$ increase and generation of reactive oxygen species (ROS). However, the mechanism of tamoxifen to link increased intracellular $Ca^{2+}$ to ROS generation is currently unknown. Thus, in this study we investigated the possible involvement of calmodulin, a $Ca^{2+}$ activated protein, and $Ca^{2+}$/calmodulin-dependent protein kinase II in the above tamoxifen-induced events. Treatment with calmodulin antagonists (calmidazolium and trifluoroperazine) or specific inhibitors of $Ca^{2+}$/calmodulin-dependent protein kinase II (KN-93 and KN-62) inhibited the tamoxifen-induced apoptosis in a dose-dependent manner. In addition, these agents blocked the tamoxifen-induced ROS generation in a concentration-dependent fashion, which was completely suppressed by intracellular $Ca^{2+}$ chelation. These results demonstrate for the first time that, despite of its well-known direct calmodulin-inhibitory activity, tamoxifen may generate ROS and induce apoptosis through indirect activation of calmodulin and $Ca^{2+}$/calmodulin-dependent protein kinase II in HepG2 cells.

• 전력전자학회논문지
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• 제9권4호
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• pp.397-404
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• 2004

본 논문에서는 농형유도발전기를 이용한 계통연계형 풍력발전시스템의 가변속제어 기법이 제안된다. 농형유도발 전기는 간접벡터제어 방식으로 동작되는데 d-축 전류에 의해 여자가 제어되고 q-축 전류에 토크가 제어된다. 이 토크제어에 의해 발전기는 풍속의 변화에 대해서 항상 최대전력을 발생하도록 가변속 제어된다. 발전된 전력은 back-to-back PWM 컨버터에 의해 계통으로 공급된다. 계통측 컨버터는 q-축 전류 제어에 의해 직류링크 전압을 제어하고 d-축 전류 제어에 의해 계통측 역률을 제어할 수 있다. 제안된 기법은 M-G세트로 구성된 터빈시뮬레이터를 이용하여 실험적으로 검증된다.

• 한국조경학회지
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• 제25권4호
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• pp.18-29
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• 1998

This study was carried out to test the theory of planned behavior in recreational choices behavior. Lotte World was chosen as study area, and college students were selected by nonprobability sampling for two waves of data collection. The first wave of data were collected one weeks into the spring semester : intention, attitude, subjective norm, and perceived behavioral control were measured. To collect the data of the second wave, the same resondents were asked their behavior, one week data of the second wave, the same respondents were asked their behavior , one week prior to the final examination : whether they visited the Lotte World or not. Polychoric correlation among variables were calculated by the PRELIS because behavior was nominal variable. Then, weighted least square method was utilized to calibrate structural equation model by the LISREL version 7.2. Structural link effect on intention among three determinants : the direct effect on intention was 0.421 and the indirect effect via intention on behavior was 0.145, respectively. However, its effect on behavior was insignificant because actual control over 'visiting of Lotte World' was relatively high. A few comments were sugested on data collection, and inclusion of new variables was discussed for the sufficiency f the theory of planned behavior.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.43.1-43.1
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• 2011

The detail simulation modeling of fully-fed induction generator is investigated through PC based MATLAB/Simulink environment. Generator's stator currents are controlled by indirect vector control method. In this method, generator side converter controls the maximum excitation (air gap flux) by stator d-axis current and controls generator torque by stator q-axis current. Induction generator speed is controlled by tip speed ratio (TSR) upon the wind speed variations in order to generate the maximum output power. The generator torque model is specified as a 3-blade wind turbine with rating, then, the model is simulated under normal operating condition and three different fault conditions. The matlab model designed for fully-fed induction generator based wind farm provides good performance under normal and grid fault conditions. It provides good results for different pwm techniques and fault conditions except the single-phase line to ground fault, which should be verified with real time data from wind farms.

• 전기학회논문지
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• 제58권10호
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• pp.1842-1848
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• 2009

This paper summarizes a data modeling for developing the baseline network analysis software of the Korean energy management system (EMS). The study is concentrated on the following aspects. First, the data for operating the each application software are extracted. Some of the EMS network application softwares are selected for basis model. Those are based on the logical functions of each software and are not considered the other softwares. Second, the common data are extracted for equipment model and topological structure of power system in Korea. We propose the application common model(ACM) that can be applied whole EMS network application softwares. The ACM model includes the hierarchy and non-hierarchy power system structure, and is connected each other using the direct and indirect link. Proposed database model is tested using the Korea Electric Power Corporation(KEPCO) system. The real time SCADA data are provided for the test. Through the test, we verified that the proposed database structure can be effectively used to accomplish the Korean EMS system.

• Journal of Power Electronics
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• 제5권4호
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• pp.289-304
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• 2005

This paper describes a simple control structure and power conditioning system for an indirect vector controlled stand-alone induction generator (IG) used to operate under variable speed. The required reactive power for the IG system is supplied by means of a capacitor bank and a voltage-source PWM converter. Using a capacitor bank to transfer the reactive power to the IG under the rated speed and no-load conditions starts the IG operation and reduces the PWM converter size. The vector control structure for the variable speed IG power conditioning system compensates for changes in the electrical three-phase and DC loads while considering the magnetizing curve of the IG. The vector control structure is developed to regulate the DC link voltage of the PWM converter and the IG output voltage. The experimental and simulated performance results of the IG power conditioning system at various speeds and loads are given and show that this proposed scheme can be used efficiently for a variable speed, wind energy conversion system.

• Journal of Power Electronics
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• 제7권2호
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• pp.97-108
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• 2007

This paper describes simple control structures for a vector controlled stand-alone induction generator (IG) for use under variable speeds. Different control principles, indirect vector control and deadbeat current control, are developed for a voltage source PWM converter and the three-phase variable speed squirrel-cage IG to regulate DC-link and generator voltages with a newly designed phase locked loop circuit. The required reactive power for the variable speed IG is supplied by means of a PWM converter and a capacitor bank to buildup the voltage of the IG without the need for a battery, to reduce the rating of the PWM converter while using only three sensors and to eliminate the harmonics generated by the PWM converter. These proposed schemes can be used efficiently for variable speed wind energy conversion systems. The measurements of the IG systems at various speeds and loads are given and show that these systems are capable of good AC and DC voltage regulation.

• Journal of Microbiology and Biotechnology
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• 제31권5호
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• pp.637-644
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• 2021

Malassezia is the most abundant genus in the fungal microflora found on human skin, and it is associated with various skin diseases. Among the 18 different species of Malassezia that have been identified to date, M. restricta and M. globosa are the most predominant fungal species found on human skin. Several studies have suggested a possible link between Malassezia and skin disorders. However, our knowledge on the physiology and pathogenesis of Malassezia in human body is still limited. Malassezia is unable to synthesize fatty acids; hence, it uptakes external fatty acids as a nutrient source for survival, a characteristic compensated by the secretion of lipases and degradation of sebum to produce and uptake external fatty acids. Although it has been reported that the activity of secreted lipases may contribute to pathogenesis of Malassezia, majority of the data were indirect evidences; therefore, enzymes' role in the pathogenesis of Malassezia infections is still largely unknown. This review focuses on the recent advances on Malassezia in the context of an emerging interest for lipases and summarizes the existing knowledge on Malassezia, diseases associated with the fungus, and the role of the reported lipases in its physiology and pathogenesis.