• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.1
• /
• pp.67-72
• /
• 2006

Questionnaire survey on performance requirement of ship’s speed such as not only accuracy but also response and robustness were carried out, and the experiments to survey the GPS performances of static and dynamic characteristics were carried out simultaneously. In this paper, the questionnaire survey focusing on docking maneuvering, some analytic results of the survey, the results of GPS performance, and the possibility of adaptation for docking maneuvering on SDME and GPS are discussed. Consequently, from the results of questionnaire survey the performance requirement of ship’s speed in docking/anchoring maneuvering have need under 1cm/sec on the standard deviation, and speed information from GPS was adopted to use maneuvering information in docking/anchoring.

• Journal of the Korean Society of Physical Medicine
• /
• v.4 no.4
• /
• pp.241-247
• /
• 2009

Purpose：The purpose of this study is to investigate the effect of transcutaneous electrical stimulation on autonomic nervous system using heart rate variability analysis. Methods：31 subjects were evaluated with HRV before and after a single high-frequency TENS for 15minutes treatment. The standard deviation of all the normal RR-interval(SDNN) and lower frequency/high frequency ratio(LF/HF ratio) were recorded with TAS-9. Results：After single TENS treatment, autonomic adaptation as analyzed by SDNN was increased from $42.47\pm12.96$ to $4.43\pm16.76$(p>0.05) and autonomic balance as analyzed by LF/HF ratio was increased from $1.4\pm0.45$ to $1.45\pm0.41$(p>0.05). Conclusion：In this study, SDNN and LF/HF ratio changed in health young students as a result of single TENS treatment. But there is no significant difference between pre-treatment and post-treatment of SDNN and LF/HF ratio.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.10 no.1
• /
• pp.5-13
• /
• 2007

The trajectory of an current artillery munition is subject to a variety of different error sources resulting in more or less big deviation from the nominal predicted flight path. The 1D CCM(Course Correction Munition) has appeared to solve this problem and the mechanism of 1D CCM is a simple and low cost one using the influence of drag to range behavior of an artillery munition. In the paper 1D CCM concept has been simulated using wind tunnel experiment results of the specified Korean munition with CCF(Course Correction Fuze) and calculated the performance of its rang error reduction. From the simulated results it can be numerically explained that the possibility of adaptation of 1D CCM concept to Korean artillery munitions.

• Proceedings of the KIEE Conference
• /
• 1987.11a
• /
• pp.351-354
• /
• 1987

In this paper, an adaptive control scheme is applied to the speed control system of a synchronous AC servo motor. The adaptive control system using Ioannou's modified adaptation law is shown to be robustly stable in the presence of current control error and load torque disturbance. The computer simulation demonstrates the rapid compensation of rotor speed deviation due to load torque disturbance.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.2
• /
• pp.99-104
• /
• 2023

The purpose of this study was to examine the effect of children's academic stress on school adaptation and to verify whether ego-resilience plays a mediating role in the relationship between academic stress and school adaptation. Based on the data from the 12th year of the Korean Children's Panel (2019), the general characteristics of the main subjects and the mean, standard deviation, skewness and kurtosis of the main variables were confirmed through basic statistical analysis, and correlation analysis was conducted between variables. In addition, to examine whether ego-resilience mediated the effect of academic stress on school adaptation, a three-step regression analysis was conducted following the procedure of Baron and Kenny. The results of this study were as follows. First, it was found that children's academic stress, school adaptation, and ego resilience were all significantly correlated. The higher the academic stress, the lower the ego-resilience and school adaptability. Second, it was confirmed that ego-resilience has a partial mediating effect in the relationship between children's academic stress and school adjustment. Ego resilience in the academic stress situation means that it acts as an important mediating factor to flexibly adapt to school life by objectively grasping and coping with the stress situation. Therefore, we need to recognize the need for flexible and resilient individual characteristics so that children can reduce academic stress and adapt well to school life, and seek active interest and intervention plans.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.7
• /
• pp.120-126
• /
• 2020

This study was a descriptive research study to investigate the relationship between self-efficacy, stress coping, and college adaptation among nursing students. The subjects were extracted from students at four-year nursing colleges in K province, and data collection was conducted from October 1 to December 10, 2018. Data analysis was done using the SPSS 22.0 program, frequency and percentage, mean and standard deviation, Pearson's correlation, t-test, ANOVA, and multiple regression. The results show that the self-efficacy of nursing college students was 3.07 ± .39, stress coping was 2.15 ± .24, and college adaptation was 3.32 ± .49. There were significant differences in college life adaptation to stress coping, depending on major satisfaction, support motivation, and drinking. The higher the subject's self-efficacy and stress coping level, the higher the adaptation to university life. In addition, there were significant differences in general characteristics according to major satisfaction, academic support motivation, and drinking. Based on the above research results, it is necessary to develop a support program to strengthen the ability to cope with stress among college students.

• The Journal of Advanced Prosthodontics
• /
• v.7 no.3
• /
• pp.199-206
• /
• 2015

PURPOSE. The present study investigated the influences of various gypsum materials on the precision of fit of CAD/CAM-fabricated prostheses and analyzed their correlation with surface roughness. MATERIALS AND METHODS. The master model of the mandibular right first molar was replicated, and four experimental groups based on two types of Type IV stone (GC Fujirock EP, Die keen) and two types of scannable stone (Aesthetic-Basegold, Everest Rock) were created to include a total of 40 specimens, 10 in each group. The surface roughness of the working models for the respective experimental groups was measured. Once the zirconia cores had been fabricated, the marginal and internal fits were measured with a digital microscope using the silicone replica technique. The mean and standard deviation of the respective points of measurement were computed and analyzed through the one-way ANOVA and Tukey's HSD test. The correlation between surface roughness and the precision of fit of the zirconia core was analyzed using the Pearson correlation analysis (${\alpha}$=.05). RESULTS. The zirconia cores fabricated from the scannable stone working models exhibited a superior precision of fit as compared to those fabricated from the Type IV stone working models. The correlation analysis results showed a clear positive correlation between surface roughness and the precision of fit of zirconia cores in all of the experimental groups (P<.05). CONCLUSION. The results confirmed that the surface roughness of dental working models has a decisive influence on the precision of fit of zirconia cores.

• The Korean Journal of Applied Statistics
• /
• v.35 no.6
• /
• pp.703-724
• /
• 2022

Although longitudinal studies mainly produce multivariate longitudinal data, most of existing statistical models analyze univariate longitudinal data and there is a limitation to explain complex correlations properly. Therefore, this paper describes various methods of modeling the covariance matrix to explain the complex correlations. Among them, modified Cholesky decomposition, modified Cholesky block decomposition, and hypersphere decomposition are reviewed. In this paper, we review these methods and analyze Korean children and youth panel (KCYP) data are analyzed using the Bayesian method. The KCYP data are multivariate longitudinal data that have response variables: School adaptation, academic achievement, and dependence on mobile phones. Assuming that the correlation structure and the innovation standard deviation structure are different, several models are compared. For the most suitable model, all explanatory variables are significant for school adaptation, and academic achievement and only household income appears as insignificant variables when cell phone dependence is a response variable.

• Journal of The Korean Society of Integrative Medicine
• /
• v.10 no.4
• /
• pp.251-259
• /
• 2022

Purpose : This study was conducted to check the effect on nursing college students' major satisfaction, adjustment to college life and nurse's image nursing students before clinical practical education. Methods : The study surveyed 209 college students majoring in nursing science in the city of B for the period of April through May 2022. The collected data were analyzed using SPSS/WIN 22.0 to determine the frequency, percentage ratio, average, and standard deviation. Statistical analyses included the t-test, analysis of variance, pearson's correlation coefficients. Results : As a result of this study, the average degree of satisfaction with majors was 3.88±.50, the average of college life adaptation was 3.26±.47, and the average of the nurse image was 3.90±.51. The major satisfaction according to the general characteristics of the study subjects showed a statistically significant difference in the motive for choosing a department (F=3.70, p=.003) and the thought of a nursing job (F=2.95, p=.004). The adjustment to college life according to the general characteristics of the study subjects showed a statistically significant difference in grade (F=3.50, p=.001), department selection motivation (F=2.69, p=.022) showed a statistically significant difference. The nurse image showed a statistically significant difference in residence type (F=6.00, p=.001) and nursing job thinking (F=2.11, p=.036). The correlation between the variables of the study subjects showed that major satisfaction was found to have a positive correlation with adjustment college life (r=.51, p<.001) and nurse image (r=.54, p<.001). It was found that adjustment college life had a positive correlation with the nurse image (r=.32, p<.001). Conclusion : The higher the degree of satisfaction with the major of nursing students prior to clinical practice education, the higher the degree of adaptation to college life. It is need to intervention studies that can improve the image of positive nursing.

• Journal of the Korean Society of Physical Medicine
• /
• v.9 no.1
• /
• pp.63-68
• /
• 2014

PURPOSE: The purpose of this study was to examine the position changes with tilt table on autonomic nervous system using heart rate variability analysis. METHODS: Fourty healthy adult males volunteered in this study. The low frequency, high frequency and low frequency/high frequency ratio and mean heart rate, standard deviation of all normal R-R intervals, root mean square of successive differences, heart rate variability index were measured at the tilt table angle of $0^{\circ}$, $45^{\circ}$ and $90^{\circ}$ with pulsoximeter. Data were analyzed one-way ANOVA and LSD post hoc test. RESULTS: The mean heart rate, low frequency and low frequency/high frequency ratio increased significantly at higher angle of tilt table(p<.05). The root mean square of successive differences, heart rate variability index decreased significantly at lower angle of tilt table(p<.05). The standard deviation of all normal R-R intervals, high frequency decreased at higher angle of tilt table did not show significant difference. CONCLUSION: The symphathetic activity increased significantly at higher angle of tilt table. The parasymphathetic activity decreased at higher angle of tilt table, but the difference were not significant. The autonomic adaptation, balance and heart rate variability decreased significantly at higher angle of tilt table. Based on these results, in the treatment of patients with a change in posture precedence should be carefully treated. Further studies are necessary to determine the most safety and effective methods.