• Journal of the Korean earth science society
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• v.25 no.4
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• pp.214-221
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• 2004

The purpose of this study is to inquire into the effects of teaching methods in the class on the conceptual change of atmospheric pressure for middle school students. After analyzing the concept of atmospheric pressure in the middle school science textbooks on the present 7th Curriculum, classes were performed adopting classified Method A and Method 3. For Method A, the textbook is used to explain the concept in the view of weight. For Method B, the textbook is used to approach the concept in the views of molecular movement as well as of weight. This study consists of four classes in the third grade students of middle school in Busan, where they were divided into the Method A group and the Method B group. These study was carried out with pre-post on each of these classes on the learning achievement and on the conceptual change of atmospheric pressure. The results of this study were as follows: First, the effect on the learning achievement was displayed the average score of the Method B was showing a meaningful difference comparing to the Method A. Second, the effect on the conceptual change measured by verifying the score for the difference among the averages for each sub-scale three out of four conceptual factors,'the direction of atmospheric influence and the reason','the principle of atmospheric action' and 'the atmospheric changes by the temperature rise on the surface of the earth and the reason', showed meaningful improvement. But, the one left factor,'the distribution of atmospheric pressure by altitudes and the reason', displayed no meaningful difference. Third, The concept of atmospheric pressure is better defined as the pressure created by the movement of air particles, in the view of kinetic theory of gas, rather than explained by the notion of the weight of air.

• Physical Therapy Korea
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• v.11 no.1
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• pp.53-67
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• 2004

This simulation study investigated the characteristics of normal gait, $30^{\circ}$ crouch gait, $30^{\circ}$ crouch/equinus gait, $45^{\circ}$ crouch gait, $45^{\circ}$ crouch/equinus gait. The knee flexion angles were restricted using a specially designed orthosis. This study was carried out in a motion analysis laboratory of the National Rehabilitation Center. Fifteen healthy male subjects were recruited for the study. The purposes of this study were (1) to compare spatiotemporal parameters, kinematics, and kinetic variables in the sagittal plane among the different gait, (2) to investigate the secondary compensatory strategy, and (3) to suggest biomechanical physical therapy treatment methods. The pattern and magnitude observed in each condition were similar to those of normal gait, except the peak knee extension moment of the unrestricted ankle motion-crouch gait. However, the speed of the $45^{\circ}$ crouch gait was half that of a normal gait. The ankle joint moment in the crouch/equinus gait showed the double-bump pattern commonly observed in children with spastic cerebral palsy, and there was no significant difference in gait speed as compared with normal gait. The peak ankle plantar-flexor moment and ankle power generated during the terminal stance in the crouch/equinus conditions were reduced as compared with normal and $45^{\circ}$ crouch gaits (p<.05). The crouch/equinus gait at the ankle joint was an effective compensatory mechanism. Since ankle plantarflexion contracture can be exacerbated secondary to the ankle compensatory strategy in the crouch/equinus gait, it is necessary to increase the range of ankle dorsiflexion and the strength of plantarflexion simultaneously to decrease the abnormal biomechanical advantages of the ankle joint.

• 한국지구과학회:학술대회논문집
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• 2004.02a
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• pp.2-12
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• 2004

The purpose for this study is to inquire into the effects of teaching methods in the class on the conceptual change of atmospheric pressure for middle school students. After analyzing the concept of atmospheric pressure in the middle school science textbooks on the present 7th Curriculum, classes were performed adopting classified Method A and Method B. For Method A, the textbook used that explains the concept in the view of weight. For Method B, the textbook used approaching to the concept in the views of molecular movement as well as of weight. This study consists of four classes in the third grade students of middle school in Busan, which were divided into the Method A group and the Method B group. The result of the study carried out pre-post each of these classes on the learning achievement and on the conceptual change of atmospheric pressure. The result of this study were as follows: First, the effect on the learning achievement was displayed the average score of the Method B was showing meaningful difference comparing to the Method A. Second, the effect on the conceptual change measured by verifying the score for the difference among the averages for each sub-scale three out of four conceptual factors, 'the direction of atmospheric influence and the reason', 'the principle of atmospheric action' and 'the atmospheric changes by the temperature rise on the surface of the earth and the reason', showed meaningful improvement. But, the one left factor, 'the distribution of atmospheric pressure by altitudes and the reason', displayed no meaningful difference. Third, The concept of atmospheric pressure is better defined as the pressure created by the movement of air particles, in the view of kinetic theory of gas, rather than explained by the notion of the weight of air.

• Korean Journal of Applied Biomechanics
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• v.31 no.4
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• pp.308-313
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• 2021

Objective: The purpose of this study was to investigate the effect of different kettlebell mass (30%, 40%, and 50% of the body mass) on kinematics and kinetic variables of kettlebell swing. Method: Total of 16 healthy male who had at least 1 year of kettlebell training experience were participated in this study (age: 31.69 ± 3.46 yrd., height: 173.38 ± 4.84 cm, body mass: 74.53 ± 6.45 kg). In this study, a 13-segments whole-body model (upper trunk, lower trunk, pelvis, both side of forearm, upperarm, thigh, and shank) was used and 26 reflective markers were attached to the body to identify the segments during the movement. A 3-dimensional motion analysis with 8 infrared cameras and 4 channeled EMG was performed to find the effect of kettlebell mass on its swing. To verify the kettlebell mass effect, a one-way ANOVA with a repeated measure was used and the statistical significance level was set at 𝛼=.05. Results: Firstly, in all lower extremity joints and thoracic vertebrae, a statistically significant change in angle was shown according to an increase in kettlebell mass during kettlebell swing (p<.05). Secondly, in both the up-swing and down-swing phases, the knee joint and ankle joint ROM showed a statistically significant increase as the kettlebell mass increased (p<.05) but no statistically significant difference was found in the hip joint and thoracic spine (p>.05). Lastly, the hamstrings muscle activity was statistically significantly increased as the kettlebell mass increased during up-swing phases (p<.05). Also, as the kettlebell mass increased in P4 of the down swing phase, the gluteus maximus showed a statistically significantly increased muscle activation, whereas the rectus femoris showed a statistically significantly decreased muscle activation (p <.05). Conclusion: As a result of this study, hip extension decreased and knee extension increased at 40% and 50% of body mass, and the spine also failed to maintain neutrality and increased flexion. Also, when kettlebell swings are performed with 50% of body mass, synergistic muscle dominance appears over 30% and 40% of body mass, which is judged to have a risk of potential injury. Therefore, it is thought that for beginners who start kettlebell exercise, swing practice should be performed with 30% of body mass. In addition, even in the case of experienced seniors, as the weight increases, the potential injury risk may increase, so it is thought that caution should be exercised when performing swings with 40% and 50% of body mass. In conclusion, it is thought that increasing the weight after sufficiently training with 30% of the weight of all subjects performing kettlebell swing is a way to maximize the exercise effect as well as prevent injury.

• Journal of Korean Medical Ki-Gong Academy
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• v.20 no.1
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• pp.118-147
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• 2020

Objective : The purpose of this study is to understand trends of pelvic correction therapy in Korea and to assist research activities on pelvic correction therapy. Also, this study selected and presented indicators for measuring pelvic slope to help ensure consistent studies with uniform indicators in future studies related to pelvic correction. Methods : The following keywords "골반", "골반 교정", "골반 변위" "Pelvic correction" were searched on three specialized search sites (RISS, NAI, DBpia). Trends in pelvic correction therapy were analyzed through the selected researches suitable among these searched researches in an overview format. Results : 1. A total of 7,806 studies were searched and a total of 268 studies were finally selected. 2. Studies began in 1977 and have been actively studied until recently, with 35 studies in 2017 being the most recent trend since 2000. 3. In the results according to the Main Field of Research, the 'Arts and Kinesiology'(113, 42.16%) and 'Medicine and Pharmacy'(103, 38.43%) were the most in order. To the Middle Field, the 'Kinesiology was the largest with 96(35.82%) studies. 4. In the results according to the study design, 'Pre-Post Test(PPT)' was the largest with 107 studies. 5. In the results according to the Intervention, 'Exercise' was the largest with 165 studies, of which 'Pilates' and 'Yoga' in 'Training' was the largest. 6. Among the evaluation method, the 'Pelvic Index' was used 146 times, followed by 'Spinal Alignment (99)', 'Other Joints (93)', and 'Kinetic Specialized Measurement Test (56)'. 7. Among the evaluation methods, the pelvic slope measurement indicators were PT (58), PH (48), Pelvic Torsion (40), Iliac Crest (38), ASIS-PSIS distance/angle (27), and Pelvic Width (I.W., I.L., S.W) (25) in order. 8. The journals that published the most researches were KJSS(Korean Alliance For Health, Physical Education, Recreation, And Dance;9), and JKPT(Korean Physical Therapy;9). Among the University, the Graduate School of Silla University published the most papers (12). 9. The author who published the most studies were Seungjin Park(3), the co-authors were Hoseong Lee, Gideok Park, Seongsu Bae(3), and the Thesis-Director Gyeongok Lee(7). Conclusions : 1. Studies on pelvic correction treatment continue to increase every year. 2. The main academic field of pelvic correction is 'Sports', 'Physical Therapy', and 'Medical Science'. 3. The most chosen research design method in the study on pelvic correction treatment was 'Pre-Post Test(PPT)', primarily as an intermediary, Pilates and yoga during exercise therapy, and then Chiropractic during handcraft were used as multiple frequencies. 4. Among the various measurement method indicators of pelvic correction previously used, multiple frequency was taken up in the order of PT, PH, Pelvic Torsion, iliac crest, ASIS-PSIS distance/angle, and pelvic width (I.W.,I.L.,S.W). Typically, measurements through "ASIS-PSIS angle" are recommended and are considered as the most rational in clinical trials.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.217-221
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• 2013

This study developed predictive models for the kinetic behavior of Staphylococcus aureus on processed cheeses. Mozzarella slice cheese and cheddar slice cheese were inoculated with 0.1 ml of a S. aureus strain mixture (ATCC13565, ATCC14458, ATCC23235, ATCC27664, and NCCP10826). The inoculated samples were then stored at $4^{\circ}C$ (1440 h), $15^{\circ}C$ (288 h), $25^{\circ}C$ (72 h), and $30^{\circ}C$ (48 h), and the growth of all bacteria and of S. aureus were enumerated on tryptic soy agar and mannitol salt agar, respectively. The Baranyi model was fitted to the growth data of S. aureus to calculate growth rate (${\mu}_{max}$; ${\log}CFU{\cdot}g^{-1}{\cdot}h^{-1}$), lag phase duration (LPD; h), lower asymptote (log CFU/g), and upper asymptote (log CFU/g). The growth parameters were further analyzed using the square root model as a function of temperature. The model performance was validated with observed data, and the root mean square error (RMSE) was calculated. At $4^{\circ}C$, S. aureus cell growth was not observed on either processed cheese, but S. aureus growth on the mozzarella and cheddar cheeses was observed at $15^{\circ}C$, $25^{\circ}C$, and $30^{\circ}C$. The ${\mu}_{max}$ values increased, but LPD values decreased as storage temperature increased. In addition, the developed models showed acceptable performance (RMSE = 0.3500-0.5344). This result indicates that the developed kinetic model should be useful in describing the growth pattern of S. aureus in processed cheeses.

• Korean Journal of Food Science and Technology
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• v.14 no.3
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• pp.197-202
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• 1982

Kinetic study for the thermal degradation of ginsenosides in ginseng extract was conducted. The results indicate that the thermal degradation followed first order kinetics and rate constants varied substantially depending on the types of ginsenosides and heat treatment temperatures. Activation energy calculated by Arrhenius plots ranged from 16.80 kcal/mole to 30.10 kcal/mole and $Q_{10}$ values ranged from 2.01 to 3.49. Correlation coefficients between the change of ginsenoside contents by thermal degradation and heat treatment temperature were $0.995{\sim}0.999$. The dependence on temperatures of the decomposition rate constant of total ginsenoside can be expressed as $k=4.574{\times}10^8$ exp(8898.8/T).

• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.29-44
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• 2005

The purpose of this study is to reveal the effects of two different kicks, the drop kick and the punt kick, into the kicking motion, through the kinetic comparative analysis of the kicking motion, which is conducted when one kicks a soccer goal. To grasp kinetic changing factors, which is performed by individual's each body segment, I connected kicking motions, which were analyzed by a two dimension co-ordination, into the personal computer to concrete the digits of it and smoothed by 10Hz. Using the smoothed data, I found a needed kinematical data by inputting an analytical program into the computer. The result of comparative analysis of two kicking motions can be summarized as below. 1. There was not a big difference between the time of the loading phase and the time of the swing phase, which can affect the exact impact and the angle of balls aviation direction. 2. The two kicks were not affected the timing and the velocity of the kicking leg's segment. 3. In the goal kick motion, the maximum velocity timing of the kicking leg's lower segment showed the following orders: the thigh(-0.06sec), the lower leg(-0.05sec), the foot(-0.018sec) in the drop kick, and the thigh(-0.06sec), the lower leg(-0.05sec), the foot(-0.015sec) in the punt kick. It showed that whipping motion increases the velocity of the foot at the time of impact. 4. At the time of impact, there was not a significant difference in the supporting leg's knee and ankle. When one does the punt kick, the subject spreads out his hip joint more at the time of impact. 5. When the impact performed, kicking leg's every segment was similar. Because the height of the ball is higher in the punt kick than in the drop kick, the subject has to stretch the knees more when he kicks a ball, so there is a significant affect on the angle and the distance of the ball's flying. 6. When one performs the drop kick, the stride is 0.02m shorter than the punt kick, and the ratio of height of the drop kick is 0.05 smaller than the punt kick. This difference greatly affects the center of the ball, the supporting leg's location, and the location of the center of gravity with the center of the ball at the time of impact. 7. Right before the moment of the impact, the center of gravity was located from the center of the ball, the height of the drop kick was 0.67m ratio of height was 0.37, and the height of the punt kick was 0.65m ratio of height was 0.36. The drop kick was located more to the back 0.21m ratio of height was 0.12, the punt kick was located more to the back 0.28m ratio of height was 0.16. 8. There was not a significant difference in the absolute angle of incidence and the maximum distance, but the absolute velocity of incidence showed a significant difference. This difference is caused from that whether players have the time to perform of not; the drop kick is used when the players have time to perform, and punt kick is used when the players launch a shifting attack. 9. The surface reaction force of the supporting leg had some relation with the approaching angle. Vertical reaction force (Fz) showed some differences in the two movements(p<0.05). The maximum force of the right and left surface reaction force (Fx) didn't have much differences (p<0.05), but it showed the tendency that the maximum force occurs before the peak force of the front and back surface (Fy) occurs.

• The Korean Journal of Nuclear Medicine
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• v.30 no.3
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• pp.299-314
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• 1996

The purpose of the present study was to validate the use of tissue radioactivity ratios instead of regional metabolic rates for the assessment of regional metabolic changes in Alzheimer's disease(AD) with [$^{18}F$]FDG PET and to examine the correlation of ratio indices with the severity of cognitive impairment in AD. Thirty-seven AD Patients(age $68{\pm}9 yrs$, $mean{\pm}s.d.$; 36 probable and 1 definite AD), 28 patients with dementia of non-Alzheimer type(age $66{\pm}7 yrs$), and 17 healthy controls(age $66{\pm}4 yrs$) underwent [$^{18}F$]FDG PET imaging. Two simplified radioactivity ratio indices were calculated from 37-66 min image: region-to-cerebellar radioactivity ratio(RCR) and a composite radioactivity ratio(a ratio of radioactivity in the most typically affected regions over the least typically affected regions: CRR). Local cerebral metabolic rate for glucose(LCMRglu) was also measured using a three-compartment, five-parameter tracer kinetic model. The ratio indices were significantly lower in AD patients than in controls(RCR in temporoparietal cortex, $0.949{\pm}0.136$ vs. $1.238{\pm}0.129$, p=0.0004; RCR in frontal cortex, $1.027{\pm}0.128$ vs. $1.361{\pm}0.151$, p<0.0001; CRR, $0.886{\pm}0.096$ vs. $1.032{\pm}0.042$. p=0.0024). On the RCR analysis, 86% of AD patients showed a pattern of bilateral temporoparietal hypometabolism with or without frontal involvement; hypometabolism was unilateral in 11% of the patients. When bilateral temporoparietal hypometabolism was considered to be suggestive of AD, the sensitivity and specificity of the RCR analysis for the differential diagnosis of AD were 86% and 73%, respectively. The RCR was correlated significantly with the macroparameter K [$K_1k_3/(k_2+k_3)$] (r=0.775, p<0.0001) and LCMRglu(r=0.633, p=0.0002) measured using the kinetic model. In patients with AD, both average RCR of cortical association areas and CRR were correlated with Mini-Mental Status Examination(r=0.565, p=0.0145; r=0.642, p=0.0031, respectively), Clinical Dementia Rating(r=-0.576, p=0.0124; r=-0.591, p=0.0077), and total score of Mattis Dementia Rating Scale (r=0.574, p=0.0648; r=0.737, p=0.0096). There were also significant correlations between memory and language impairments and corresponding regional RCRs. The results suggest that the [$^{18}F$]FDG PET ratio indices, RCR and CRR, reflect global and regional metabolic rates and correlate with the severity of cognitive impairment in AD. The simplified ratio analysis may be clinically useful for the differential diagnosis and serial monitoring of the disease.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.7
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• pp.826-832
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• 2007

Unpleasant tastes and odors in drinking water cause same problems for water utilities across Korea. Even though tastes and odors do not create health problems, they are main concerns for consumers who determine the safety of their drinking water. In this study, two different odor producing compounds(geosmin 2-MIB) in the Nakdong river water and rapid sand filtered rater were treated by advanced oxidation of $O_3/H_2O_2$ process. The experimental results showed that the removal efficiency of geosmin with the use of 5 mg/L of $O_3$ and $H_2O_2$ was higher than efficiency with the use of $O_3$ alone for both the raw water and the sand filtered water. And in general, the removal efficiency of geosmin was higher than 2-MIB in the sand filtered water. Under the range of $O_3$ concentration $0.5\sim2.0$ mg/L, the removal rate constants(k) of geosmin for the raw and sand filtered waters, and the one of 2-MIB in the sand filtered water were increased rapidly as doses of $O_3$, and $H_2O_2$, increased. The removal rate constants(k) do not increase any more when $H_2O_2/O_3$ ratio increases above the optimum ratio. The optimum ratio of $H_2O_2/O_3$, dose was $1.0\sim2.0$ for both geosmin and 2-MIB. The removal rate constant(k) becomes lower when OH radical consuming materials are present in raw water. The half-life of geosmin decreased rapidly as the $O_3$ and $H_2O_2$ doses increase in the sand filtered water. The half life decreased about 8.5 times with the use of 2 mg/L of $O_3$ and 10 mg/L of $H_2O_2$ than with the use of 2 mg/L of $O_3$ alone for the sand filtered water.