• Journal of the Korean GEO-environmental Society
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• v.15 no.2
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• pp.27-36
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• 2014

Due to the latitudinal location of Korea, the seasonally frozen ground has been focused on as research topics such as the frost heaving under the asphalt road rather than the permafrost ground. However, the recent construction of the second Korean Antarctic research station, the Jangbogo station and the participation on the development of the natural gas pipeline in Russia arouse the research interests on the behavior of the permafrost ground. At the design process of the geotechnical structures on the permafrost ground, the evaluation of the creep characteristics of the frozen soil is very crucial. Since the domestic specification on the frozen soil testing does not exist currently, it is necessary to evaluate the creep characteristics of frozen soils systematically with regard to the affecting factors. Therefore, the creep characteristics of the frozen specimens of dense Jumoonjin sand were evaluated under various loads at -5 and $-10^{\circ}C$. Based on the test results, as the load became close to the strength and the temperature became lower, the duration of the secondary creep became shorter and more distinct tertiary creep responses were observed.

• 재활복지
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• v.21 no.1
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• pp.253-277
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• 2017

The purpose of this study was to develop the Constraints in Physical Activity Scale for people with physical Disabilities(CPASD) which measures the constraints in physical activity of people with physical disabilities. For this study, the 5 step analytic framework of unified validity developed by Messick (1995), the framework for conducting a strong program of construct validation by Benson (1998) method were applied. Furthermore, the validity of CPASD was systematically presented by applying common factor model and measurement model to 264 persons with physical disabilities. The conclusion based on the results and discussions of this study is as follows. First, CPASD presented evidence of job validity. Four factors (17 items) were developed, consisting of leader constraints, economic constraints, prejudice, and exercise environment constraints through the analysis of the factor structure and the fit of factor coefficients. Second, the factor structure of the developed CPASD (leader constraint, economic constraint, prejudice, exercise environment constraint) was statistically distinguished and stably reflected the existing exercise participation constraints theory. Third, the developed CPASD presented evidence of the validity of the criteria. Leader constraints and prejudice were negatively correlated with positive motor emotions, leader constraints, prejudice, and exercise environment constraints were positively correlated with negative motor emotions. Therefore, in future research, it is necessary to reevaluate the current system and actual condition related to leader constraints, economic constraints, prejudices, and exercise environment constraints derived as factors of CPASD. To do this, it is necessary to judge the degree of reality based on the causal relationship verification and IRT theory using CPASD.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.218-228
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• 2019

This study was conducted to review and analyze the academic-related satisfaction intervention programs for Korean nursing students and to provide evidence-based data. The data included in the meta-analysis were 25 studies published from 2001 to July 2018, and the design of the study consisted of 1 randomized controlled trial and 24 non-randomized controlled trials. The study subjects were nursing students from 1st to 4th grade, and the intervention program was conducted in theoretical and practical classes. The sample size was 1182 (mean: 47.3) in the experimental group and 1137 in the control group (mean: 45.5). The intervention program consisted of 1~16 weeks/1~16 sessions/7~240 minutes per session. Dependent variables were as follows: major satisfaction, learning satisfaction, satisfaction with the classroom practice, and satisfaction with the clinical practice. Satisfaction with the classroom practice (Hedges' g=0.876[95% CI: 0.405, 1.346]), satisfaction with the clinical practice (Hedges' g=0.515[95% CI: 0.312, 0.718]), and overall academic-related satisfaction (Hedges' g=0.630[95% CI: 0.371, 0.889]) were statistically significant and above intermediate levels in the meta-analysis. The study results are significant in that the objective results were confirmed by integrating the previous studies dealing with the academic-related satisfaction intervention program of nursing students.

• Korean Journal of Construction Engineering and Management
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• v.20 no.6
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• pp.126-131
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• 2019

The estimation of available solar energy at particular locations is critical to find and assess suitable locations of PV sites. The amount of PV power generation is however affected by various geographical factors (e.g., weather), which may make it difficult to identify the complex relationship between affecting factors and power outputs and to apply findings from one study to another in different locations. This study thus undertakes a regression analysis using data collected from 172 PV plants spatially distributed in Korea to identify critical weather conditions and estimate the potential power generation of PV systems. Such data also include solar radiation, precipitation, fine dust, humidity, temperature, cloud amount, sunshine duration, and wind speed. The estimated PV power generation is then compared to the actual PV power generation to evaluate prediction performance. As a result, the proposed model achieves a MAPE of 11.696(%) and an R-squred of 0.979. It is also found that the variables, excluding humidity, are all statistically significant in predicting the efficiency of PV power generation. According, this study may facilitate the understanding of what weather conditions can be considered and the estimation of PV power generation for evaluating and determining suitable locations of PV facilities.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.5
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• pp.683-690
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• 2021

The ventilation system of the engine room of a ship is generally installed to supply the combustion air necessary for the internal combustion engine and to remove the heat source generated in the engine room, and it must satisfy the international standard (ISO 8861) for the design conditions and calculation standards for the ventilation of the ship engine room. The response delay of the ventilation system including the fire detector is affected by the airflow formed inside the area and the location of the fire detector. In this study, to improve the initial fire detection response speed of a fire detector installed on a fishing vessel and to maintain the sensitivity of the installed detector, the smoke behavior was simulated using the air flow field inside the engine room, the amount of combustion air in the internal combustion engine, and the internal pressure of the engine room as variables. Analysis of the simulation results showed that reducing the flow rate in the air flow field and increasing the vortex by reducing the internal pressure of the engine room and installing a smoke curtain would accelerate the rise of the ceiling of the smoke component and improve the smoke detector response speed and ventilation system.

• Therapeutic Science for Rehabilitation
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• v.10 no.2
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• pp.95-108
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• 2021

Objective : This study aimed to develop prototypes of "smart stacking cones" by combining ICT to evaluate and train the upper extremity function and dual task performance in patients with central nervous system impairment, and to identify the complementary point to the completion of the device through a usability test. Methods : This prototype comprised of a hardware and software system that enabled the evaluation and training of patients and the management of data obtained from patients' performance. Specific measurement variables were established so that patient performance could be measured correctly. Based on the measurement variables, a the prototype included a 'single task evaluation modes', 'dual task evaluation mode', 'single task training mode', and 'dual task training modes'. Additionally, a usability test was conducted to assess clinical applicability and overall satisfaction for the prototype. Results : The results of the usability test were generally found to be appropriate. The 'content adequacy' in the usability test was the area with the highest level of adequacy and the lowest level of inadequacy. Additionally, overall 'satisfaction' in the usability test was the area with the highest appropriate and inappropriate levels. Hence, the overall satisfaction results were unstable. Conclusion : Future studies should be conducted to identify the clinical effectiveness of the device by applying an upgraded smart stacking cone to an actual patient group.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.5
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• pp.60-67
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• 2021

According to the 「Guidelines of Structural Design for Piloti Building」 of the Ministry of Land, Infrastructure and Transport (2018), the natural period of middle and low rise building of upper-walled lower frame type, such as the domestic multiplex house in piloti style, is suggested for safety to apply the existing code formula of the wall structure. However, the current code formula of the wall structure was provided based on actual measurement of high-rise wall-type structures that mainly exhibit bending behavior. So it is considered that it is not suitable for a piloti-type house with four stories or less, where the wall behaves in shear. See also Park et al. (2000) confirmed that the effect of the lower frame part is greater than that of the upper wall part in the natural period of complex structures with 10 or more floors through analytical studies. Therefore, in this study, in order to examine the effect of the lower frame on the natural period of the middle and low-rise piloti structure, the estimation of natural period by the finite element analysis, approximation formula and ccurrent code formula was performed for the target structures with the shear and flexural stiffness of the upper wall and the shear stiffness of the lower frame as variables. As result, it was found that the change in the shear stiffness of the lower frame had a greater effect on the natural period of the whole building than the change in the bending or shear stiffness of the upper wall.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.4
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• pp.75-82
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• 2021

The objective of this study is to examine the loss of prestressing stress in the developed prestressing reinforcing units using steel bar and pipe (SP). The main parameters were the reinforcing bar type, the magnitude of prestressed force, and prestressing method. The test results showed that the loss of prestressing stress for SP was highest in the initial prestressing step, which was higher for the compression introduction typed specimens than tension introduction typed specimens. The loss of prestressing stress of SP made with P800 was 1.6% for the compression introduction typed specimen with 0.8f_y, which was lowest than the other specimens. Meanwhile, the relaxation of SP with the respect to the time ranged between 0.4 and 1.9%, irrespective of SP material type, the magnitude of prestressed force, and prestressing method. These values were less than 2.5%, which is the maximum value for the relaxation of prestressed reinforcing steel bars in design codes. Consequently, considering the loss of stress developed in the initial prestressing step, the developed SP material type, prestressing introduction method, and magnitude are recommended to be P800, compression introduction type, and 0.8f_y.

• Journal of vocational education research
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• v.29 no.3
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• pp.265-289
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• 2010

This study aims to identify effects of outplacement support program for discharged soldier to settle and adapt successfully in Ministry of Patriots and Veterans Affairs. The subject of this study are 323 discharged soldiers who completed the outplacement support program. A survey questionnaire is conducted to measure variables of this study. All data analysis is accomplished using the AMOS 7.0 version. The results of this study are as follows. First, learning motivation has direct effect on learning flow and program satisfaction positively. Second, organizational support has direct effect on program satisfaction, psychological stability positively and on learning flow negatively. Third, outplacement support program has direct effect on learning flow, program satisfaction, job-seeking efficacy and psychological stability positively. Fourth, learning flow has direct effect on program satisfaction positively but don't have direct effect on job-seeking efficacy and psychological stability significantly. Fifth, learning motivation, outplacement support program has direct effect on job-seeking efficacy and psychological stability with partial mediation effect of program satisfaction while without mediation effect of learning flow. Based on the results of the study, the following recommendations have been made. First, it is necessary to design the outplacement support program with contents in relation to discharged soldiers' successful settlement because discharged soldiers who completed the outplacement support program showed higher job-seeking efficacy and psychological stability. Second, it is needed to conduct a longitudinal study considering other variables such as employment, establishment success etc.

• Survey Research
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• v.18 no.4
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• pp.127-147
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• 2017

Despite the importance of questionnaires, little survey methodology research on questionnaire design has been conducted in Korea. The purpose of this study was to explore whether two questionnaire forms (close-ended vs. open-ended questions) about 'the most important problem in Korea' elicited similar responses. During the 2016 Korean General Social Survey (KGSS), a random half of respondents were asked the open-ended question form and the remaining half were asked the close-ended question form. While the economy is the most mentioned response (35% vs. 33.2%) to both close-ended and open-ended question forms, there is similarity in the order of highly mentioned responses if we consider that 'politics' is not provided as one of response categories in the close-ended question form. The order of second to fourth response category is crime (24.4%), education (15.4%), and poverty (6.3%) to the closed-ended question form, and politics (10.8%), crime (9.5%), and education (7.6%) to the open-ended question form. Also, the characteristics of respondents who responded with the economy as being the most important are slightly different between the two halves in terms of age, household income, and satisfaction with economic condition. Our findings suggest that we need to be careful when we adopt questions developed in other countries and to consider using survey experiments in pre-testing questionnaire items.