• 한국수학교육학회지시리즈C:초등수학교육
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• 제3권1호
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• pp.1-36
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• 1999

The case of four classrooms analyzed in this study point to many commonalities in the challenges of reforming mathematics teaching in Korea and the U. S. In both national contexts we have seen the need fur a clear distinction between implementing new student-centered social practices in the classroom, and providing significant new loaming opportunities for students. In particular, there is an important need to distinguish between attending to the social practices of the classroom and attending to students conceptual development within those social practices. In both countries, teachers in the less successful student-centered classes tended to abdicate responsibility fur sense making to the students. They were more inclined to attend to the literal statements of their students without analyzing their conceptual understanding (Episodes KA5 and UP 2). This is easy to do when the rhetoric of reform emphasizes student-centered social practices without sufficient attention to psychological correlates of those social practices. The more successful teachers tended to monitor the understanding of the students and to take proactive measures to ensure the development of that understanding (Episodes KO5 and UN3). This suggests the usefulness of constructivism as a model (or successful student-centered instruction. As Simon(1995) observed, constructivist teachers envision a hypothetical learning trajectory that constitutes their plan and expectation for students learning from the particular if the trajectory is being followed. If not, the teacher adjusts or supplements the task to obtain a more satisfactory result, or reconsider her or his assumptions concerning the hypothetical learning trajectory. In this way, the teacher acts proactively to try to ensure that students are progressing in their understanding in particular ways. Thus the more successful student-centered teacher of this study can be seen as constructivist in their orientation to student conceptual development, in comparison to the less successful student-centered teachers. It is encumbant on the authors of reform in Korea and the U. S. to make sure that reform is not trivialized, or evaluated only on the surface of classroom practices. The commonalities of the two reform endeavores suggest that Korea and the U. S. have much to share with each other in the challenges of reforming mathematics teaching for the new millennium.

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.3017-3029
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• 2023

In the late in-vessel phase of a nuclear reactor severe accident, the internal heat transfer and crust evolution during the debris bed melting process have important effects on the thermal load distribution along the vessel wall, and further affect the reactor pressure vessel (RPV) failure mode and the state of melt during leakage. This study coupled the phase change model and large eddy simulation to investigate the variations of the temperature, melt liquid fraction, crust and heat flux distributions during the debris bed melting process in the hypothetical severe accident of HPR1000. The results indicated that the heat flow towards the vessel wall and upper surface were similar at the beginning stage of debris melting, but the upward heat flow increased significantly as the development of the molten pool. The maximum heat flux towards the vessel wall reached 0.4 MW/m². The thickness of lower crust decreased as the debris melting. It was much thicker at the bottom region with the azimuthal angle below 20° and decreased rapidly at the azimuthal angle around 20-50°. The maximum and minimum thicknesses were 2 and 90 mm, respectively. By contrast, the distribution of upper crust was uniform and reached stable state much earlier than the lower crust, with the thickness of about 10 mm. Moreover, the sensitivity analysis of initial condition indicated that as the decrease of time interval from reactor scram to debris bed dried-out, the maximum debris temperature and melt fraction became larger, the lower crust thickness became thinner, but the upper crust had no significant change. The sensitivity analysis of in-vessel retention (IVR) strategies indicated that the passive and active external reactor vessel cooling (ERVC) had little effect on the internal heat transfer and crust evolution. In the case not considering the internal reactor vessel cooling (IRVC), the upper crust was not obvious.

• 대한간호학회지
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• 제42권1호
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• pp.9-18
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• 2012

Purpose: The purpose of this study was to test the turnover intention model for chief nurse officers in general hospitals. The variables for the study included job stress, social support, job satisfaction, and organization commitment. Methods: A predictive, non-experimental design was used with a sample of 144 chief nurse officers from 144 general hospitals. Data were collected using self-administered questionnaires and analyzed using SPSS, AMOS program. Results: The overall fitness of the hypothetical model to the data was good (${\chi}^2$=16.80, p=.052, GFI=.96, AGFI=.90, NFI=.97, CFI=.99). Job stress, social support, job satisfaction, and organization commitment explained 59.0% of the variance in turnover intention by chief nurse officers. Both organization commitment and social support directly influenced turnover intention for chief nurse officers, and job stress and job satisfaction indirectly influenced turnover intention. Conclusion: The results imply that chief nurse officers in hospitals need social support and management of job stress to increase job satisfaction and organization commitment, and lower turnover intention.

• 대한간호학회지
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• 제43권6호
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• pp.812-820
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• 2013

Purpose: The purpose of this study was to construct a structural equational model to explain and predict burnout in family caregivers of patients with cancer. The study was based on the Stress-Appraisal-Coping Model of Lazarus and Folkman (1984) and Family Stress Theory (Hill, 1958). Methods: Data were collected from July 10 to September 30, 2012 through direct interviews and a self -report questionnaire survey. Participants in this study were 206 family caregivers providing care for patients with cancer in In-patient or Out-patient departments of three different general hospitals located in Busan. Measured variables were exogenous variables (social support and perceived health status) and endogenous variables (perceived stress, hope and burnout). Results: Goodness of fit in the hypothetical model was ${\chi}^2=174.07$, TLI=.95, CFI=.97, RMSEA=.08. Perceived health status, perceived stress, and hope showed statistically significant direct effects on burnout of family caregivers. Social support affected burnout of family caregivers indirectly. These variables explained 68.5% of total variance in burnout. Conclusion: The results from this study suggest that perceived stress, perceived health status, and hope should be considered as major influential factors when developing nursing interventions to control burnout of family caregivers (of patients with cancer).

• 대한간호학회지
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• 제44권3호
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• pp.259-269
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• 2014

Purpose: The purpose of this study was to construct and test a structural equation modeling on burnout of clinical nurses based on CS-CF model. Methods: A survey using a structured questionnaire was conducted with 557 clinical nurses. Data were analyzed using structural equation modeling. Results: The modified hypothetical model yielded the following ${\chi}^2=289.70$, p<.001, RMSEA=.09, GFI=.93, TLI=.91, CFI=.94, PCFI=.65, AIC=363.21, SRMR=.05 or less and showed good fit indices. Nursing work environment, patient safety culture and resilience showed indirect effects on burnout while compassion fatigue and compassion satisfaction had direct effects. Conclusion: Results of this study suggest that compassion fatigue must be decreased and compassion satisfaction has to be increased, while burnout is lowered by enhancing the clinical nursing work environment, patient safety culture and resilience. In addition, more variables and longitudinal studies are necessary to validate the clear cause-and-effect relationship between the relevant variables.

• 임상간호연구
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• 제18권3호
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• pp.341-353
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• 2012

Purpose: This study was done to construct a hypothetical model to explain the factors influencing career commitment of nurses. Methods: Three factors (individual internal-, job- and career-characteristics) and 8 sub-factors were measured with Likert scales. Data collection was conducted from Jan. 11 to 31, 2011 using self-report questionnaires. Participants(738 nurses) were selected from 6 hospitals in 2 metropolitan cities of South Korea. Collected data were analyzed using SPSS Window 16.0 and Amos 19.0. Results: 1) Among the 3 factors, career commitment was most strongly influenced by career-characteristics. 2) Career commitment wasinfluenced by organizational-career-management but not by personal-career-management. 3) Career commitment was influenced by individual internal-characteristics but not by job-characteristics. 4) Of the 8 sub-factors, career commitment was most strongly influenced by desire-for-growth but not by self-efficiency. Conclusion: The results of this study indicate that in order to improve career commitment of nurses it is necessary to implement custom-made career development policies considering individual characteristics in the organizational level.

• 지역사회간호학회지
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• 제22권3호
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• pp.325-332
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• 2011

Purpose: This study examined the fitness of a path model on the relationship among perceived health status, self-esteem, self-efficacy, and Yangsaeng for elderly women. Methods: The subjects consisted of 633 aged women. Data were collected through self.report questionnaires. The data were analyzed with the SPSS and AMOS programs. Results: Perceived health status, self-esteem, and self-efficacy showed a direct effect on elderly women's Yangsaeng while perceived health status and self-esteem showed an indirect effect on their Yangsaeng. Perceived health status and self-esteem showed a direct effect on elderly women's self-efficacy. The hypothetical path model of elderly women's Yangsaeng was proven correct. Conclusion: These results suggest that elderly women's Yangsaeng can be enhanced by increasing their perceived health status, self-esteem and self-efficacy. Based on the outcomes of this study, it is necessary to design an intervention program that emphasizes the enhancement of perceived health status, self-esteem and self-efficacy in order to improve elderly women's Yangsaeng.

• 대한간호학회지
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• 제41권4호
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• pp.491-499
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• 2011

Purpose: The study was conducted to develop and test a hypothetical model which explains self-care behavior in patients with type 2 diabetes was established based on the Self-Determination Theory. Methods: The participants were 218 patients with type 2 diabetes mellitus enrolled in an outpatient clinic of one endocrine center in Korea. The data were collected using questionnaires from April 5 through May 7, 2010. The descriptive and correlation statistics were analyzed using the SPSS/WIN 15.0 and the structural equation modeling procedure was performed using the AMOS 7.0 program. Results: The results of this study showed that competence and autonomous motivation were the strong factors influencing self-care behavior in patients in this sample. Support from health provider for autonomy was a significant indirect factor on self-care behavior. These factors explained 64.9% of variance in the participants' self care behavior. The proposed model was concise and extensive in predicting self-care behavior of the participants. Conclusion: Findings may provide useful assistance in developing effective nursing interventions for maintaining and promoting self-care behavior in patients with type 2 diabetes.

• 여성건강간호학회지
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• 제22권4호
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• pp.210-220
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• 2016

Purpose: The purpose of this study was to construct and test a structural equation modeling on the reproductive health behavior of single women with sexual experiences. This study employed Ajzen's Theory of Planned Behavior (TPB). Methods: The data were collected after receipt of consent from 250 single women with sexual experiences, and analyzed using SPSS 18.0 and AMOS 18.0. Results: Model fit indices for the hypothetical model were suitable for the recommended level: $x^2=362.407$, RMR=0.065, RMSEA=0.070, GFI=0.867. TLI=0.927, CFI=0.938, IFI=0.939, and $x^2/dF=2.237$. Intention showed direct effect with the biggest effect being on reproductive health behavior. Attitude, subjective norm and perceived behavioral control were found to have a direct effect on intention. Among them, perceived behavioral control revealed the largest influence. Conclusion: This study suggests that the TPB is a suitable model in explaining the reproductive health behavior of single women with sexual experience. Strategic plans for educational and intervention programs should be aimed to encourage single women to engage in reproductive health behavior.

• 대한간호학회지
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• 제39권2호
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• pp.229-236
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• 2009

Purpose: This study was a secondary analysis to verify the mediating role of organizational citizenship behavior (OCB) between organizational justice (OJ) and organizational effectiveness (OE) in nursing organizations. Methods: The RN-BSNs and their colleagues in Seoul and Busan were subjects. The data was collected for 20 days between September 13 and October 2, 2004. Two hundred eighty three data sets were used for the final analysis. The fitness of models were tested using AMOS 5. Results: The fitness of hypothetical model was moderate. Procedural Justice (PJ), Interaction Justice (IJ) and Distributive Justice (DJ) had direct effects on Job Satisfaction (JS), Organizational Commitment (OC) and Turnover Intention (TI) in OE, and indirect effects on JS, OC and TI mediated by OCB. The modified model improved with ideal fitness showed the causal relations among OE. In modified model, PJ, IJ and DJ had direct positive effects on OCB and JS and OC in OE, and indirect effects on JS and OC mediated by OCB. JS and OC in OE had a direct negative effect on TI. Conclusion: OCB mediated the relationship between OJ and OE, so the nursing managers should enhance OCB of the nurses in order to improve OE.