• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.49 no.10
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• pp.859-870
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• 2021

KARI (Korea Aerospace Research Institute) is developing a design framework for the concept and preliminary design of eVTOL aircrafts. A low fidelity mission analysis tool was developed for the eVTOL aircrafts of Lift-Tilt Concept, which have tilt propellers and lift propellers, using open source SUAVE package. For its development, a review for the propeller performance analysis functionality was made. To find the trim solution at each mission segment automatically, an algorithm is implemented, using a global optimization technique through parallel processings and DOE(design of experiment). Using the tool, the one seated eVTOL OPPAV(optionally piloted personal air vehicle) was modeled and evaluated, which results were compared with the preliminary design data.

• The Journal of Korean Academic Society of Nursing Education
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• v.25 no.3
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• pp.331-343
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• 2019

Purpose: This study focuses on investigating the effectiveness of simulation education on emergency management using a low-fidelity simulator as related to clinical skill performance, self-confidence, knowledge, learning satisfaction, and critical thinking disposition in new nurses. Methods: A pre-post test experimental design of nonequivalent control group was applied. Fifty-five new nurses were recruited, 28 nurses for the experimental group and 27 nurses for the control group. A simulation education for emergency management comprising knowledge lecture, team learning, skill education, team simulation, and debriefing was developed and implemented from Feb. 14 to 27, 2015. Data were analyzed with percentage, average, and standard deviation, chi-square, and t-test using SPSS. Results: The experimental group showed significantly higher knowledge (t=5.81, p<.001), clinical skill performance (t=10.08, p<.001), self-confidence (t=-6.24, p<.001), critical thinking disposition (t=2.42, p=.019), and learning satisfaction (t=4.21, p<.001) for emergency management compared with the control group who had traditional lecture education. Conclusion: The results indicate that a simulation education using a low-fidelity simulator is an efficient teaching method for new nurses to deepen their clinical skill performance, self-confidence, knowledge, learning satisfaction, and critical thinking disposition in learning emergency management.

• Journal of Korean Physical Therapy Science
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• v.28 no.1
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• pp.54-61
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• 2021

Background: The present study was performed to examine the factors required for active engagement of participants in exercise therapy by surveying the frequency of participation, fidelity of performance, and supporting materials and rewards provided to encourage participation in the study. Design: Cross-sectional study. Methods: The survey was conducted in a population of 103 participants in at least one exercise treatment study. A 12-item questionnaire was designed to determine the frequency of exercise participation and fidelity of participant performance. Results: The results were subjected to frequency analysis and Pearson's correlation analysis. The subjects were less likely to exercise with the therapist and less likely to exercise at home. In addition, the provision of supplementary materials, to be considered when exercising at home, was insufficient. A strong positive correlation was found between the frequency of exercise in the presence of a therapist and the fidelity of participant performance (r=0.812, p=0.001), whereas a weak negative correlation was found between the frequency of unperformed exercises and the fidelity of participant performance (r=-0.523, p=0.023). Conclusion: The results of the present study suggested that it is necessary to increase the number of times that exercises are performed with the therapist to motivate increased frequency of exercise participation and fidelity of participant performance. In addition, appropriate rewards and periodic management are required.

• Journal of the Korea Society for Simulation
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• v.30 no.1
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• pp.21-29
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• 2021

This paper introduces experimental design and components model for analysing the impact of parameter(in the field of kinematics and sensor) on performance of hard-kill torpedo defence system. The simulation is implemented at the level of engagement and its scope is limited to final stage of engagement where main function of anti-torpedo system is operating. It improves the fidelity of physical realism by precise model of simulation components in the perspectives of kinematics, sensor capability and acoustic detection theory. This paper provides the experimentation methodology for evaluating parameter sensitivity which is required to analyze in advance of development the defense system with novel concepts. In addition, the experimental result shows the tendency of defense capability according to parameter adjustments.

• Journal of dental hygiene science
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• v.15 no.5
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• pp.560-568
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• 2015

The aim of this study was to provide basic data that could give a positive effect for both new dental hygienists and dental institutions by identifying the impact of one the job training on the organizational socialization, targeting 162 new dental hygienists who currently worked in dental clinic. The data were analyzed using the chi-squire, independent-samples t-test, hierarchical regression analysis. It was shown that the characteristics and contents of a duration of inservice training for new dental hygienists, difficulty, satisfaction, and details of on-the-job training affected organizational socialization by 26.1%. The factor that had the greatest impact on the organizational socialization was dental hygiene service training, followed by guidance of hospital service regulations. This study was significant in that it applied the concept of organizational socialization to the dental hygienists. The future study on the more effective and systematic training program will be needed to help new dental hygienists be socialized more effectively in the new organization.

• Journal of Animal Science and Technology
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• v.50 no.5
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• pp.581-590
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• 2008

Growth curves for ultrasonic carcass traits such as longissimus muscle area, backfat thickness and marbling score as well as chest girth which was simultaneously measured when carcass traits were investigated using ultrasound measuring technique were estimated to identify growth patterns and to adjust maturing effects in order to evaluating genetic merits on cows in farming basis. 27,410 records from 22,451 cows on which of 15~90 month of age were investigated from the national wide of Korea using by ultrasonic scanning techniques by the skilled persons from 2002 to 2007. Van Bertalanffy growth function was applied for estimating growth curves on these traits. Carcass traits and chest girth would be linearly increased by body condition score. It might be used for multiplicative correction factors for pre- adjustment on the body condition scores. Growth pattern on chest girth would be quickly reached to mature size and stable on after reached to asymptotic mature size. Longissimus muscle area would also be reached to mature size but little smoother than chest girth. Otherwise, growth curve on backfat thickness would be steadily increasing up to 7 years of age. It also showed large individual difference by way of mean square error. Marbling score would be steadily increased but sharper than those on backfat thickness. It would be reached to mature size up at 5 years of age. Those growth curves would be used for correcting function on age at investigating on genetic evaluation system.

• Korean Journal of Cognitive Science
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• v.23 no.4
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• pp.517-551
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• 2012

We are imitating animals. True imitation can be defined as a learning to do an act from seeing it done by others. We have been building culture by imitating others' skills and knowledge with high fidelity. In this regard, it is important to ask how the faculty of imitation has evolved and how imitation behaviors develop ontogenetically. It is also interesting to see whether nonhuman animals can imitate truly or not and how different imitation learning is among human and non-human animals. In this paper, first I review empirical data from imitation studies with human and nonhuman animals. Comparing different species, I highlight their different levels of copying fidelity and explain the reason why they are showing the difference. Then I review recent studies on neurobiological mechanisms underlying imitation. The initial neurobiological studies on imitation in humans suggested a core imitation circuitry composed of mirror neuron system [inferior parietal lobule(IPL) and inferior frontal gyrus(IFG)] and the posterior part of the superior temporal sulcus(pSTS). More recent studies on the neurobiology of imitation, however, has gone beyond the studies on the core mechanisms. Finally, I try to find out implications of psychology and biology of imitation for cultural evolution. I argue for a memetic approach to cultural evolution, along the lines with a recent study on measuring memes by mirror neurons system.

• The Journal of the Acoustical Society of Korea
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• v.19 no.7
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• pp.66-76
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• 2000

Acoustic performance of loudspeakers for sound reproduction has been qualitatively evaluated by using the listening test by juries in the development and final evaluation stages. However, the subjective evaluation method has many problems in the viewpoint of reliability and repeatability that are mainly related to the jury performance, as well as time and economy. In this reason, objective techniques should be tried to evaluate the acoustic performance of loudspeakers as well as the conventional subjective test. The object of this study is to find if there is any correlation between the statistically treated in test results and the measured results based on the loudness of reproduced sound signals. For the four-step statistical analysis, the analysis of variance (ANOVA) and Tukeys method are employed for dealing with the data from the listening test. For the objective evaluation, Zwickers loudness considering the human hearing characteristics is calculated for the measured sound signal emitted from each loudspeaker and the objective ratings such as fidelity rating (FR) and softness rating (SR) is suggested. The correlation between two ratings has been demonstrated for an actual set of loudspeakers using FR, SR and correlation coefficient. The method in this study can be useful in statistically evaluating commercial or prototype loudspeakers without using very time-consuming and expensive subjective testing.

• Journal of Korean Society of Forest Science
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• v.99 no.6
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• pp.849-854
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• 2010

This study was conducted to investigate the variation of seed and germination characteristics among populations and among individuals within populations of Abies koreana Wilson distributed in Korea. Cones was collected from 4 natural populations and their seven seed qualities as well as three germination behaviors was measured and tested. Statistical analysis showed that there were significant differences among populations as well as among individuals within populations in 8 traits except for percentage of sound seeds and seed vigor. Coefficients of variation in percentage of sound seeds, germination percentage and germination rate is relatively high (43.8~57.2%) compared to other traits (11.0~28.3%). The germination of seed started on the seventeen day after sowing and it was completed within seventy-nine days. The final seed germination capacity was found high except for Mt. Duckyu (8.5%) and varied from 39.7% to 47.7%. Mean germination time ranged between 38.1 and 43.6 days and germination rate varied from 1.98 to 1.39 ea./days. As a result of simple correlation analysis between seed characteristics and germination characteristics, the percentage of sound seeds showed a significant positive correlation with the germination percentage and the germination rate but showed a negative correlation with the mean germination time.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.696-702
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• 2009

Yellow poplar (Liriodendron tulipifera L.) is an insect-pollinated tree species with large, perfect flower, and its seed sets average only about 10 percent naturally. In its controlled pollination, pollination bags are usually taken to prevent unwanted pollination, but bagging is an expensive and time-consuming process. Therefore, this study was conducted to determine the need of pollination bag by estimating how much unintended pollination would occur when different cross methods were applied. Five different pollination methods were applied as follows: 1) natural open pollination (i.e. insect pollination) as a reference, 2) self-pollination; no removing reproductive organs with bagging, 3) open pollination; emasculated(removing sepal, petal and stamen) without bagging, 4) controlled pollination; emasculated with bagging and 5) controlled pollination; emasculated without bagging. Very low value of full seed rate (0.2%) was observed in method 3, it was suggested that removing stamen and petal restrict the activity of pollen vectors like bee. Difference in the full seed rate between method 4 and method 5 was not significant (27.9% versus 24.0%, respectively). Consequently, controlled pollination without bagging might be an alternative method for extensive breeding and mass production of seeds in yellow poplar.