• Macromolecular Research
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• v.12 no.1
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• pp.1-10
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• 2004

The structural changes occurring in the isothermal crystallization processes of polyethylene (PE), poly-oxymethylene (POM), and vinylidene fluoridetrifluoroethylene (VDFTrFE) copolymer have been reviewed on the basis of our recent experimental data collected by the time-resolved measurements of synchrotron-sourced wide-angle (WAXS) and small-angle X-ray scatterings (SAXS) and infrared spectra. The temperature jump from the melt to a crystallization temperature could be measured at a cooling rate of 600-1,000 $^{\circ}C$/min, during which we collected the WAXS, SAXS, and infrared spectral data successfully at time intervals of ca. 10 sec. In the case of PE, the infrared spectral data clarified the generation of chain segments of partially disordered trans conformations immediately after the jump. These segments then became transformed into more-regular all-trans-zigzag forms, followed by the formation of an orthorhombic crystal lattice. At this stage, the generation of a stacked lamella structure having an 800-${\AA}$-long period was detected in the SAXS data. This structure was found to transfer successively to a more densely packed lamella structure having a 400-${\AA}$-long period as a result of the secondary crystallization of the amorphous region in-between the original lamellae. As for POM, the formation process of a stacked lamella structure was essentially the same as that mentioned above for PE, as evidenced from the analysis of SAXS and WAXS data. The observation of morphology-sensitive infrared bands revealed the evolution of fully extended helical chains after the generation of lamella having folded chain structures. We speculate that these extended chains exist as taut tie chains passing continuously through the neighboring lamellae. In the isothermal crystallization of VDFTrFE copolymer from the melt, a paraelectric high-temperature phase was detected at first and then it transferred into the ferroelectric low-temperature phase at a later stage. By analyzing the reflection profile of the WAXS data, the structural ordering in the high-temperature phase and the ferroelectric phase transition to the low-temperature phase of the multi-domain structure were traced successfully.

• Korean Institute of Interior Design Journal
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• v.26 no.2
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• pp.22-32
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• 2017

This research is to analyze the spatial information search features which shown by Eye fixation and movement and conducted eye tracking experiment for targeting sports shop spatial images which it are same but looks different. This is able to find out the eye movement feature according to placement of goods from the eye movement and movement distance of spatial visitor, and the result can be defined as following. First, the whole original-reverse left / right images have a higher number of observations in the [IN] area than in the [OUT] area. This is because after eye taking high observations in LA area of [IN] have been jump-over [OUT], performed search activities in low eye fixation without high eye fixation. Second, there was a difference in the frequency of the observation data as the composition of the images changed. The original image has been often fixed the eyes in LA area, and the one that has been observed for a long time is reverse left / right image. Also, fixation point was shown higher at the reverse left / right image as jump-over from [OUT] area to [IN] area. If LA area seen as reverse left / right image, it is located in right-hand side. The case where the dominant area is on the right side has a characteristic that the eye fixation is longer. This can be understand that the arrangement of products for attract the customer's attention in the commercial space might be more effective when it is on the right side. Third, the moving distance(IN ${\rightarrow}$ OUT) of the sight pointed to external from LA area was long in the both original-reverse left / right images, but it is no relation with search direction([IN${\rightarrow}$OUT] [IN${\rightarrow}$OUT]) of the sight. In other words, the sight that entered in LA area can be seen as visual perception activity for re-searching after big jump-over, in the case go in to outward (OUT area) after searching for more than certain time. The fact that the moving distance of eye is relatively short in the [IN ${\rightarrow}$ OUT] process considered as that the gaze that stays outside the LA area naturally enters in to LA area.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.309-317
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• 2018

The purpose of this study was to investigate the effect of bone age on physique and physical fitness in elementary school students. For this purpose, the structural equation model test was conducted based on the three-year longitudinal study. The results were as follows. First, bone age in boys and girls (1st~3rd grade) has a direct effect on the change of body size, but it does not affect the change of physical strength. Second, the bone age of the senior male students(4~6 grade) gave a direct effect on the change of physique, 50m running, and sit-up. On the other hand, it gave an indirect effect on push-ups, sitting basketball throws, and standing long jump. Third, the bone age of the female students(grades 4~6) affected directly on body size change, sit-up, side step and indirect effect on 50m running, half squat jump, and standing long jump. These results indicated that the evaluation of the bone age of the subjects should be included in the exercise ability evaluation items for the male and female students in elementary school over the fourth grade in relation to the myofunction.

• Exercise Science
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• v.21 no.2
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• pp.183-190
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• 2012

This study is to evaluate the availability of cardiorespiratory fitness measurement by 20 m shuttle run test based upon energy contribution rates of elite athletes in different sports type. Sixty-seven elite athletes attending K national university participated in this study. They were divided by three groups based upon sports type, composed of Anaerobic Group (sprint, jumps, weightlifting, throw; n=35), Aerobic Group (medium-long distance; n=9), and Combat Sport Group (judo; n=23). 20 m shuttle run test was conducted by Leger et al.(1982) method and calculating acceleration using measured shuttle run repetitions was conducted by Brewer et al.(1988) method. To test the usefulness of VO₂max, graded exercise treadmill test was conducted and standing long jump and 50 m run were measured as power fitness factors. Z-jump was used for measuring power, agility, and muscular endurance. Standing long jump and 50 m run of Anaerobic Group (AnG) was significantly higher than that of Aerobic Group (AeG) and Combat Sport Group (CG) (p<0.05). However, Z-jump of CG was significantly higher than that of AnG and AeG(p<.05). There was a higher correlation of 20 m shuttle run test and VO₂max in AnG(r= 0.577, p<.0001) and CG(r= 0.760, p<.0001). Otherwise, there was a low correlation of 20 m shuttle run test and VO₂max in AeG. There was no significant group difference to test the availability of 20 m shuttle run test and there was a reduced error when converting 20 m shuttle run results into VO₂max. This study examined the usefulness of 20 m shuttle run test by converting 20 m shuttle run repetition results into VO₂max calculation, which showed reduced error. Therefore, this study confirmed that it would be needed to convert 20 m shuttle run results into VO₂max for universal and practical use in the field without dividing sports type.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.544-552
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• 2020

This study investigated the effectiveness of "Healing Stay in Forest," a long-term stay forest therapy program implemented by National Center for Forest Therapy in 2019 with 49 participants by measuring pre- and post-questionnaire responses and physical changes, such as blood pressure, body composition, and HRV. Results confirmed statistically significant reduction in negative emotions and enhancement of autonomic nerve balance in the participants. Regarding the changes in the evaluation of physical fitness based on medical history, some significant differences were observed in grip strength and standing high jump, in which participants with no medical history showed better results than those with medical history. These findings are important for verifying the effectiveness of long-term stay forest therapy (6 nights and 7 days).

• PNF and Movement
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• v.17 no.2
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• pp.177-187
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• 2019

Purpose: The purpose of this study was to investigate the effects of combined training on the physical fitness of male short distance athletes. Methods: Combined training was applied with CLT and isokinetric training three times a week for eight weeks. For CLT, elastic bands were used in the sitting and standing positions to gradually increase sprint and skating movements. Isokinetic training was conducted at $60^{\circ}/sec$ and $180^{\circ}/sec$ to improve muscle strength and muscle power. Results: After the application of combined training, strength (hand force) improved from 42.25 kg to 47.30 kg. Muscle power for standing long jump improved from 240.00 cm to 248.80 cm, while the sergeant jump improved from 55.00 cm to 58.00 cm. Isokinetic testing showed that muscle strength ($60^{\circ}/sec$) improved from 315.65 %BW to 365.79 %BW for the left extensor and from 306.60 %BW to 325.00 %BW for the right extensor. The left flexor improved from 177.23 %BW to 189.47 %BW, but the right flexor decreased slightly from 210.87 %BW to 201.53 %BW. Muscle power ($180^{\circ}/sec$) improved from 254.00 %BW to 293.00 %BW for the left extensor and from 256.00 %BW to 272.00 %BW for the right extensor. The left flexor improved from 150.00 %BW to 162.00 %BW and the right flexor from 145.25 %BW to 182.00 %BW. Conclusion: Combined training could be used as a physical training program for male short distance athletes.

• Journal of the Korean Applied Science and Technology
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• v.38 no.6
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• pp.1606-1615
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• 2021

The purpose of this study is to provide basic data for injury prevention and performance improvement by developing a flywheel training program for handball players. The results of analyzing the effects of the 12-week complex flywheel training program on body composition, physical fitness factors, anaerobic power, and isokinetic muscle function are as follows. There was a significant difference between groups in push-ups. Body fat percentage and anaerobic power showed significant differences in the interaction by period. Long jump, slow jump, grip strength, back muscle strength, anaerobic average power, and isokinetic muscle function tests showed significant differences by period in the left and right flexors. Therefore, it is considered that 12-week flywheel training results can be used as the basic data for injury prevention and improvement of performance in handball players.

• Journal of the Korean Applied Science and Technology
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• v.39 no.4
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• pp.527-534
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• 2022

The purpose of this study was to investigate the effects of 12 weeks of muscle power and agility training on physical fitness factors and isokinetic muscle function in elementary school male soccer players. For this purpose, 6 muscle power and agility training programs were organized for 12 elementary school male soccer players and were conducted 3 times a week for 12 weeks. The results of measurement and analysis of physical fitness factors before and after the muscle strength and agility training are as follows. First, there was a significant difference in the standing long jump in place of muscle power(p<.001). Second, there was a significant difference in the standing vertical jump of muscle power(p<.05). Third, there was a significant difference in the side step of agility(p<.01). As a result, 12 weeks of muscle power and agility training can be expected to have a positive effect on the improvement of agility and agility of elementary school male soccer players, and it is judged that it can provide training basic data for injury prevention and performance improvement.

• Journal of the Korean Data and Information Science Society
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• v.23 no.2
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• pp.309-315
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• 2012

The purpose of this study was to examine the comparison of physique with physical fitness according to TBS (Talented-Educational in Sport) program by H University in 2009-2011. For this study, 668 elementary students (2009: 297, 2010: 194, 2011: 177 or 1st: 506, 2nd: 104, 3rd: 58) were collected who aged 7 to 13 living in Seoul and Gyeonggi area. The subjects were measured on physique variables (5) and physical fitness variables (7). Mean comparisons (ANOVA) were conducted for each gender in order to compare the mean differences among attendance number. For association analysis, Pearson correlation coefficient was used to find association between the physique and physical fitness variables. Some physical fitness variables (sit up, half squat jump, side step, standing long jump, flexibility in male children; sit up, half squat jump, side step in female children) increased significantly in the attendance number but the physique variables did not. The results show that TES program was effective on the physical fitness variables (muscle endurance & agility) in sports talent children.

• Korean Journal of Mathematics
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• v.22 no.3
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• pp.529-552
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• 2014

As we know, some indices and data are strong influence to the price movement of some assets now, but not to another assets and in future. Thus we define some asset models for several time intervals; intraday, weekly, monthly, and yearly asset models. We define these asset models by using Brownian motion with volatility and Poisson process, and several deterministic functions(index function, twitter data function and big-jump simple function etc). In our asset models, these deterministic functions are the positive or negative levels of auxiliary indices, of analyzed data, and for imminent and extreme state(for example, financial shock or the highest popularity in the market). These functions determined by indices, twitter data and shocking news are a kind of one of speciality of our asset models. For reasonableness of our asset models, we introduce several real data, figurers and tables, and simulations. Perhaps from our asset models, for short-term or long-term investment, we can classify and reference many kinds of usual auxiliary indices, information and data.