• The KSFM Journal of Fluid Machinery
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• v.13 no.4
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• pp.37-43
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• 2010

The purpose of this study is not only to investigate the effects of air layer in the turbine chamber on the performance and internal flow of the cross-flow turbine, but also to suggest a newly developed air supply method. Field test is performed in order to measure the output power of the turbine by a new air supply method. CFD analysis on the performance and internal flow of the turbine is conducted by an unsteady state calculation using a two-phase flow model in order to embody the air layer effect on the turbine performance effectively. The result shows that air layer effect on the performance of the turbine is considerable. The air layer located in the turbine runner passage plays the role of preventing a shock loss at the runner axis and suppressing a recirculation flow in the runner. The location of air suction hole on the chamber wall is very important factor for the performance improvement. Moreover, the ratio between air from suction pipe and water from turbine inlet is also significant factor of the turbine performance.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.2
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• pp.189-201
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• 2019

The purpose of this study is to identify elements of job crafting impacts on work engagement and individual work performance in Vietnamese commercial banks. The research data, collected from 226 bank officers, uses the quantitative research tools as: Cronbach's Alpha Analysis, Explanatory Factor Analysis, Confirmatory Factor Analysis as well as Structural Equation Modeling. The results of the hypothesis test show that only two hypotheses (H2, H3) are accepted: the impact of cognitive crafting on work engagement of bank officers (H2) and the impact of work engagement on individual work performance (H3). However, three remaining relationships (H1, H4, H5) are not accepted in the study: the impact of relational crafting on work engagement of bank officers (H1), the impact of relational crafting on individual work performance of bank officers (H4) and the impact of cognitive crafting on individual work performance of bank officers (H5). The study results indicate that cognition on job crafting leaves positive impacts on work engagement, leading to individual work performance enhancement. On the other hand, the relational crafting element implies contribution on neither collective nor individual working performances. Furthermore, no direct effect of cognition on job crafting to individual performance has been identified.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.11
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• pp.133-143
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• 2021

This study investigates the relationship between social capital and enterprise performance with knowledge sharing as the mediator. By employing the data of 677 respondents collected from delivering questionnaires to small and medium-size firms in Vietnam in 2020, this study suggests a two-step approach that combines exploration factor analysis (EFA), confirmatory factor analysis (CFA), and path analysis (SEM). The empirical findings significantly support our proposed model by demonstrating that knowledge sharing mediates the connection between all three elements of social capital and enterprise performance. At the same time, the results emphasize the importance of knowledge sharing as a major benefit of social capital and a substantial driving element of both operational and financial performance. The results show that all three social capital qualities (structural, relational, and cognitive) significantly impact both tacit and explicit knowledge sharing, while knowledge is one of the main routes connecting social capital to enterprise performance. Hence, our research model may be used in future studies to evaluate social capital, knowledge sharing, and firm performance as a new theoretical model. Our results offer a plausible explanation for how social capital improves knowledge sharing and enterprise performance.

• Journal of Korean Academy of Nursing Administration
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• v.5 no.1
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• pp.39-61
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• 1999

This thesis is attempted to ananlyze the relationship between the empowerment in the nursing work environment, the job-related personal charateristics and the nursing job performance according to the individual variables of hospital, age, experience, education, position, practice area, number of nurses in the practice area, number of beds. 'Opportunity', 'support', 'informantion', ,resource' are used as structural factors of empowerment suggested by Kanter's theory of structural power in organization, and 'self-efficacy', 'burnout', 'motivation', 'organizational commitment' are defined as four job-related personal charateristics. The ultimate goal of this study is to find out the work effectiveness of the structural factors of empowerment and the job-related personal charateristics. The basic data consists of two sets of questionaires. One is the self-reporting quetionaires for the staff nurses and the other one is questionaires answered by nursing managers. The latter is designed to objectively measure the job performance. A total of 523 items of data are collected randomly from nursing population of 7 different university teaching hospitals in Seoul metropolitan area. The data were analyzed mainly using descriptive statistics, correlation analysis. ANOVA, and Duncan test according to the various purposes of the analysis. The main results of this study are as follows : 1. The mean score of four structural empowerment factors are ranked by support, opportunity, resource, and information. And among the four job-related personal charateristics self-efficacy factor shows especially high score. 2. The results of the correlation analysis between the empowerment factors and the job-related personal charateristics are as follow: 1) The 'opportunity' factor is correlated with organizational commitment' (r=.37), 'motivation' (r=.36), 'burnout' (r=-.17), and (r=.09). 2) The 'information' factor is correlated with 'organizational commitment' (r=.44), 'motivation' (r=.39), 'burnout' (r=-.24), and 'self-efficacy' (r=.17), 3) The 'support' factor is correlated with 'organizational commitment' (r=.47). 'motivation' (r=.42), 'burnout' (r=-.24), and 'self-efficacy (r=.20), 4) The 'resource' factor is correlated with 'burnout' (r=-.28), 'organizational commitment' (r=.26), and 'motivation' (r=.26), 3. The job performance are correlated with 'motivation' (r=.24) , 'self-efficacy' (r=.16), 'burnout' (r=-.16) and 'organizational commitment' (r=.12), 4. The job performance are correlated with' support' (r=.17), 'information' (r=.12) 'opportunity' (r=.10), 5. The result of ANOVA for analysing the relationship between the structural factors of empowerment and individual variables shows that the level of empowerment are significantly different by the variables such as 'hospital' and 'the number of beds in the practice area'. In summary, there were several findings in this study, First, the structural factors of empowerment defined as opportunity, support, information are significantly correalted with the job-related personal charateristics that are supposed to relate to the level of job performance. These results support the basic hypothesis suggested by Kanter's theory and implies that for improving the job performance of nurses, hospital has to have more concern about the structural factors of nursing environment.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.6
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• pp.455-462
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• 2013

The effects of earthquakes can be devastating especially to existing structures that are not based on earthquake resistant design. This study proposes a steel grid shear wall that can provide a sufficient lateral resistance and can be used as a seismic retrofit method. The pushover analysis was performed on RC structure with and without the proposed steel grid shear wall. Obtain the performance point that the target structure for seismic loads applied to evaluate the response and performance levels. The capacity spectrum at performance point is nearly elastic range, so satisfied the performance objectives(LS level). And response modification factor(R factor) were calculated from the pushover analysis. The R factor approach is currently implemented to reflect inelastic ductile behavior of the structures and to reduce elastic spectral demands from earthquakes to the design level. The R factor increases from 2.17 to 3.25 was higher than the design criteria. As a result, according to reinforcement by steel grid shear wall, strength, stiffness, and ductility of the low-rise RC structure has been appropriately improved.

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.6 s.165
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• pp.942-954
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• 2007

The purpose of this research is to examine the level of SCM activity, marketing capability, and firm performance for apparel firms, and to investigate the effect of SCM activities and marketing capabilities for firm performance improvement. This study surveyed domestic apparel manufacturing brands that distribute products nationwide. The data was collected through questionnaires sent to managers or executives in large and middle manufacturing corporations among Korea's listed and registered corporations. The data collection has been carried out from November 10 until December 11, 2006. The questionnaires were transmitted by individual visit, fax, and mail. A total of 98 completed responses were returned, three incomplete responses were discarded. The results were as follows: First, SCM activity was classified into 3 dimensions: structural, logistical, and technological factor. Three dimensions of marketing capability were identified with differentiation, cost-leadership, and operational factor. Firm performance was classified into three dimensions: financial, productivity, and customer satisfaction factor. Second, result of analyzing effects of SCM activities for firm performance improvement, it was found that the improvement of technological activities affected acquirement of financial, productivity, and customer satisfaction performs. Structural activities affected factor of productivity performs. Third, result of analyzing effects of marketing capabilities for firm performance improvement, improvement of differentiation capabilities affected acquirement of financial, customer satisfaction performs. And the improvement of operational capability affected acquirement of financial performs and improvement of cost-leadership capability affected factor of productivity performs.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2807-2810
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• 2003

In this paper, we propose a fuzzy control method for improving the control performance by automatically tuning the scaling factor. The proposed method is that automatically tune the input scaling factor and the output scaling factor of fuzzy logic system through neural network. Used neural network is ADALINE (ADAptive Linear NEron) neural network with delayed input. ADALINE neural network has simple construct, superior learning capacity and small computation time. In order to verify the effectiveness of the proposed control method, we performed simulation. The results showed that the proposed control method improves considerably on the environment of the disturbance.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.177-177
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• 2000

In this paper, we propose a two-input two-output fuzzy controller to improve the performance of transient response and to eliminate the steady state error. The outputs of this controller are the control input calculated by position-type fuzzy controller and the accumulated error scaling factor. Here, the accumulated error scaling factor is adjusted on-line by fuzzy rules according to the current trend of the controlled process. To show the usefulness of the proposed controller, it is applied to several systems that are difficult to get satisfactory response by conventional PD controllers or PI controllers.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.268-271
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• 2001

This paper describes the power factor control of doubly fed induction machine using fuzzy logic algorithm in wind power generation system. Under fuzzy logic control, which enables superior dynamic performance, the power factor is independently controllable by decoupled d, q rotor experimental results are presented.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.9
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• pp.1185-1194
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• 2000

The characteristics of intake port flow and engine performance with swirl ratio variance in a turbocharged D.I. diesel engine were studied in this paper. The intake port flow is important factor which have influence on the engine performance and exhaust emission because the properties in the injected fuel depend on the combustion characteristics. Through these experiments it can be expected to satisfy performance and emission by optimizing the main parameters; the swirl ratio of intake port, injection timing and compression ratio. The swirl ratio for ports was modified by hand-working and measured by impulse swirl meter. For the effects on performance and emission, the brake torque and brake specific fuel consumption were measured by engine dynamometer, NOx and smoke were measured by gas analyzer and smoke meter. The results of steady flow test are as follows; as the valve eccentricity ratio are closed to cylinder wall, the flow coefficient and swirl intensity are increased. Also we realized that there is a trade-off that the increase of swirl ratio decreases mean flow coefficient and increases the Gulf factor. And the optimum parameters to meet performance and emission through engine test are as follows; the swirl ratio 2.43, injection timing BTDC 13oCA and compression ratio 15.5.