• Journal of Digital Convergence
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• v.13 no.10
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• pp.377-383
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• 2015

This study evaluates the convergence radiation protection performance by measuring the PSNR(peak signal-to-noise ratio) values of the image J in the image evaluation program based on increased relative to this exposure of radiation workers.The aim of this study was to evaluate radiation protection performance of apron for design of it's basic information. Method was used to PSNR of Image J program and good condition apron was more than 27dB, the PSNR value of poor condition apron appeared to be less than 24dB. The result is the normality were satisfied distribution and T-test values were statistically significant with p<0.001. Results of evaluation of the performance protective apron through the more easily accessible experimental conditions and methods in the clinical was confirmed distinctly different. in order to reduce the radiation exposure we need to evaluate convergence protection performance and to be having a good performance apron.

• Journal of the Korean earth science society
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• v.35 no.4
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• pp.267-276
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• 2014

The purpose of this study is to investigate the effects of problem-solving inquiry teaching using concept sketches on conceptual changes about plate tectonics and science-related attitudes. The subjects of this study were two classes of second-year students of K high school located at Anseong in Gyeonggi Province. Before instruction, a conceptual test was conducted to survey student's preconceptions about plate tectonics. The control group took a traditional lesson, while the experimental group was applied to problem-solving inquiry teaching using concept sketches. After the inquiry instruction, TOSRA (Test of Science-Related Attitudes) was administered to find out changes in science-related attitudes of the two groups. The results of this study are as follows. The experimental group understood concepts of plate tectonics better than the control group, which means that problem-solving inquiry teaching using concept sketches was more effective in students' conceptual understanding. Science-related attitudes of the experimental group showed a significant change in the categories of 'normality of scientists', 'pleasure of science lessons', and 'interests on science as a hobby'. In conclusion, the instruction of problem-solving inquiry using concept sketches produced students' positive changes in conceptual understanding about plate tectonics and science-related attitudes.

• Journal of Korean Society of Forest Science
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• v.109 no.2
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• pp.211-222
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• 2020

This study tried to find out whether there is a change over time in the functional classification of forests in relation to human demand for forests. The level in which the concept of ecosystem services has been considered in national forest management plans was also examined. A total of 98 current and previous national forest management plans were available for this study. The composition ratios of the six functions of forests in both the current and previous national forest management plans were surveyed. We used a parametric t-test when the mean values of two (current and previous) groups were normally distributed and used nonparametric Wilcoxon code rank test when the assumption of normality was not met. Timber production forests were shown to follow a normal distribution, while five others, including water regeneration forests, disaster prevention forests, natural environment conservation forests, recreation forests, and living environment conservation forests were not shown to follow a normal distribution. Timber production forests and natural environment forests showed significant changes in the proportion of forest area between previous and current forest management plans. The concept of 'ecosystem services' began to actively appear in the 6th Basic Forest Plan, which started in 2018. However, the level of frequency of the ecosystem services mentioned varied by Regional Forest Services.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.4
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• pp.387-392
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• 2016

Purpose: The aim of this study was to investigate the effects of grooved abutments on abutment screw loosening. Materials and methods: This study was conducted to evaluate the abutment screw loosening after 6 months for 50 patients (51 implants) treated at the department of Prosthodontics in Yonsei University Dental Hospital from March, 2015 to July, 2015. A control group with non-grooved abutment consists of 30 implants, and an experimental group with grooved abutment consists of 21 implants. Astra, Straumann, Implantium, Osstem system were used in the study. The abutments with loose screws cases after a period of 6 months has been investigated, with two kinds of measurements: 1) measuring the additional rotational angle on abutment during placement with the same force, 2) measuring the PTV on bucco-cervical area of implant crown. All data collected has been analyzed by normality test followed by Mann-Whitney test using SPSS program. Results: No complications were reported after 6 months for the 51 implants. Abutment screw loose and crown fracture have not been seen in the study groups. The data collected from the two measurements showed no significant differences between the two groups with P-value 0.576 (average= control group: $7.35^{\circ}$, experimental group: $4.75^{\circ}$) for the additional rotational angle measurement and with P-value 0.767 for PTV. Conclusion: There are no significant differences between the grooved and non-grooved abutment in screw stability. However, further studies with long-term followups and larger group of patients is needed in order to investigate the effects of grooved abutment on screw stability.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.2
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• pp.103-109
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• 2020

Purpose: The purpose of this study was to evaluate the preload maintenance of the retaining screw when using anaerobic sealing agents in implant fixture and abutment components. Specifically, the study examines the effects of anaerobic sealing agents on different types of screws. Materials and methods: External hexagon implants made of titanium and anti-rotational abutments were used. Titanium abutment screws and ebony abutment screws from the same manufacturer were used. The experiment was divided into four groups (n = 10 in each group). In the control group, no sealing agent was used at the implant fixture and abutment screw interface. All abutment screws were tightened according to the manufacturer's recommended torque (30 N.cm). After 24 hours, the removal torque (detorque) of each screw was measured using a digital torque gauge device. The data were analyzed by two-way ANOVA test according to normality distribution satisfaction. Results: Looking at the results for each group, titanium screws and no treatment showed detorque values of 20.3 ± 1.6 N.cm. titanium screws and applied anaerobic sealing agent showed detorque values of 32.4 ± 6.7 N.cm. Ebony screws and no treatment showed detorque values of 20.2 ± 1.5 N.cm. ebony screws and applied anaerobic sealing agent showed detorque values of 30.4 ± 4.5 N.cm. Conclusion: The detorque value was higher in the case of using anaerobic sealing agents in both the titanium screw and ebony screw groups. But there was no difference between the two screws.

• Korean Journal of Animal Reproduction
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• v.22 no.3
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• pp.287-292
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• 1998

The objective of this study was to test whether ZP drilling using a 1.48$\mu$m diode laser beam on mouse IVF embryos becomes effective the hatching and normal in vivo development, as a preliminary test for obtaining the additional proof that the 1.48$\mu$m diode laser could be used safely for human applications. The results obtained in this experiment were as follows: when the hatched rates of mouse embryos by laser ZP drilling according to the embryonic stage were examined until 72 hr (in case of blast tocyst: day 4 after IVF) or 120 hr (in case of 4-cell: day 2 after IVF) after treatment, the d data of laser drilled blastocysts (81.8%) was significantly higher than those of control (hatching blastocyst: day 4 after IVF) (54.2%) and laser drilled 4-cell embryos (45.5%) (p<0.05). When the effect of laser drilling on implantation rates following embryo transfer in day 3 synchronized pseudopregnant recipients was examined, the l laser drilled group (48.7%) was slightly higher than that of control group (43.6%). In addition, when the several pregnant mice delivered in two groups were analysed their chromosomal normality and tested reproductive ability, all p pups were presented normal chromosomal number (n=40) and showed normal growth and reproductive ability. Therefore, these results dem-onstrated that ZP drilling using a 1.48$\mu$m diode l laser can increase the embryo hatching and ind duce the normal pregnancy of mouse embryos.

• Journal of the Korean Data and Information Science Society
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• v.28 no.2
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• pp.339-348
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• 2017

One of the major issues of statistical process control for variables data is monitoring both the mean and the standard deviation. The traditional approach to monitor these parameters is to simultaneously use two seperate control charts. However there have been some works on developing a single chart using a single plotting statistic for joint monitoring, and it is claimed that they are simpler and may be more appealing than the traditonal one from a practical point of view. When using these control charts for variables data, estimating in-control parameters and checking the normality assumption are the very important step. Nonparametric Shewhart-Lepage chart, proposed by Mukherjee and Chakraborti (2012), is an attractive option, because this chart uses only a single control statistic, and does not require the in-control parameters and the underlying continuous distribution. In this paper, we introduce the Shewhart-Lepage chart, and propose the design procedure to find the optimal diagnosis limits when the location and the scale parameters change simultaneously. We also compare the efficiency of the proposed method with that of Mukherjee and Chakraborti (2012).

• Journal of Broadcast Engineering
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• v.25 no.6
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• pp.973-979
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• 2020

This study aims to objectively and quantitatively determine the social emotion of empathy by collecting pupillary response. 52 subjects (26 men and 26 women) voluntarily participated in the experiment. After the measurement of the reference of 30 seconds, the experiment was divided into the task of imitation and spontaneously self-expression. The two subjects were interacted through facial expressions, and the pupil images were recorded. The pupil data was processed through binarization and circular edge detection algorithm, and outlier detection and removal technique was used to reject eye-blinking. The pupil size according to the empathy was confirmed for statistical significance with test of normality and independent sample t-test. Statistical analysis results, the pupil size was significantly different between empathy (M ± SD = 0.050 ± 1.817)) and non-empathy (M ± SD = 1.659 ± 1.514) condition (t(92) = -4.629, p = 0.000). The rule of empathy according to the pupil size was defined through discriminant analysis, and the rule was verified (Estimation accuracy: 75%) new 12 subjects (6 men and 6 women, mean age ± SD = 22.84 ± 1.57 years). The method proposed in this study is non-contact camera technology and is expected to be utilized in various virtual reality with smart glasses.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.4
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• pp.325-332
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• 2022

Determination of VLBI IVP (Very Long Baseline Interferometry Invariant Point) position with high accuracy is required to compute local tie vectors between the space geodetic techniques. In general, reflective targets are attached on VLBI antenna and slant distances, horizontal and vertical angles are measured from the pillars. Then, adjustment computation is performed by using the mathematical model which connects measurements and unknown parameters. This indicates that the accuracy of the estimated solutions is affected by the accuracy of the measurements. One of issues in local tie surveying, however, is that the reflective targets are not in favorable condition, that is, the reflective sheet target cannot be perfectly aligned to the instrument perpendicularly. Deviation from the line of sight of an instrument may cause different type of measurement errors. This inherent limitation may lead to incorrect stochastic modeling for the measurements in adjustment computation procedures. In this study, error characteristics by measurement types and pillars are analyzed, respectively. The analysis on the studentized residuals is performed after adjustment computation. The normality of the residuals is tested and then equal variance test between the measurement types are performed. The results show that there are differences in variance according to the measurement types. Differences in variance between distances and angle measurements are observed when F-test is performed for the measurements from each pillar. Therefore, more detailed stochastic modeling is required for optimal solutions, especially in local tie survey.

• Physical Therapy Korea
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• v.30 no.1
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• pp.50-58
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• 2023

Background: This study was carried out to determine whether non-face-to-face physical therapy would have similar exercise effects to face-to-face physical therapy. Hence, we developed an approach for patients, unable to visit hospitals due to circumstances such as the COVID-19 pandemic, to conduct physical therapy comfortably at home. Objects: This study aimed to compare the effects of a face-to-face and a non-face-to-face physical therapy treatment on improving a rounded shoulder posture. Methods: The participants with rounded shoulders were randomly divided into a face-toface group (n = 15) and a non-face-to-face group (n = 15), and each group performed exercises for four weeks. The exercise program consisted of the bare hands exercise, Thera-Band exercise, and foam roller exercise. The participants in the face-to-face group came to a designated place to perform their exercises, and those in the non-face-to-face group performed the exercises at their own home using Google Meet (Google). Acromial height, total scapular distance (TSD), shoulder pain and dysfunction index (SPADI), and pectoralis minor thickness were measured. Data analysis was performed using the R Statistical Software (R Core Team), and a normality test was performed using the Shapiro-Wilk test. Results: There were no significant differences between the face-to-face and the non-face-toface groups (p > 0.05). When comparing the differences before and after the exercises, both the face-to-face and the non-face-to-face groups showed significant differences in acromial height, SPADI, and pectoralis minor thickness (p < 0.05), and both groups showed no significant difference in TSD before and after the exercises (p > 0.05). Conclusion: The results of this study support the results of previous studies reporting that shoulder stabilization exercise and pectoralis minor stretching training improves round shoulders. In addition, this study revealed that both the face-to-face and the non-face-to-face physical therapy treatments had therapeutic effects.