• Korean Journal of Applied Biomechanics
• /
• v.15 no.2
• /
• pp.119-127
• /
• 2005

The purpose of this research helps to make full use for perfect performance by grasping the defects of Ropez motion performed by athlete CSM who was under the training for the 28th 2004 Athene Olympic Garnes, and by presenting complementary methods. For the better Ropez motion which had been performed by CSM for the 1st dispatch selection test and the final for the 28th Athene Olympic Game was analyzed with 3-dimensional cinematographic method. Here are the conclusions: 1. During the board contact phase, powerful kicking and rapid forward flexion motion of upper body make increasing vertical velocity of C. O. G and enlarging body angle. 2. It was indicated that rapid forward flexion motion of upper body during the board contact phase get a large body angle in horse take-off. 3. rapid forward flexion motion of upper body during the board contact phase makes a longer time at horse contacting phase. It showed that this result increased velocity of horse take-off causing by powerful blocking motion. 4. Increasing of air-borne height during pre- flight phase, makes a higher C. O. G; and larger angle of hip, angle of knee and body angle in the landing phase. And it revealed that these results have a stable landing.

• Korean Journal of Applied Biomechanics
• /
• v.22 no.3
• /
• pp.349-356
• /
• 2012

This study aimed to assess the effects of progressive lumbar stability exercises and lumbar stability exercises on changes in the transversus abdominis muscle thickness and lower extremity muscle fatigue index in soccer players. Ten subjects were assigned to undergo training in each of the 2 groups, namely, the progressive lumbar stability exercise group and lumbar stability exercise group. Each intervention session lasted for 30 min, and 4 sessions were conducted in a week for 6 weeks for soccer players of S. University in Jeonnam, Korea. Changes in the transversus abdominis muscle thickness and lower extremity muscle fatigue index were measured using ultrasound and surface electromyogram. The results of the ultrasound measurement for the transversus abdominis muscle thickness indicated that progressive lumbar stability exercises were more effective than lumbar stability exercises. The results of the lower extremity muscle fatigue index measurements using surface electromyogram indicated that the fatigue index decreased in the progressive lumbar stability exercise group. Progressive lumbar stability exercise is believed to have put more workload during the shaking of the limbs, leading to increased stability and increased efficiency of the lower extremity muscle, thereby decreasing the fatigue index. Therefore, progressive lumbar stability exercises can be an effective measure for preventing injuries and improving the game performance of sports players by increasing the transversus abdominis muscle thickness and decreasing the lower extremity muscle fatigue index.

• Journal of the Korean Society of School Health
• /
• v.16 no.2
• /
• pp.97-110
• /
• 2003

The purpose of this study is to find out the relationship between internet addiction and mental health of 5-6th grade students in elementary schools and to provide some basic data to develop a program for prevention and treatment of internet addiction. The study is the research of the descriptive correlation and the subjects of the study were 643 students from 5th and 6th year children of four elementary schools in four districts which are located in G city. The data were analyzed by SAS program with frequency, percentage, means, standard deviation, x2-test, ANOVA and Pearson's Correlation Coefficient. The results were as follows: 1. In the demographic characteristics of the subjects, the boys were 50.5%, girls 49.5% and 5th grade students were 48.4%, 6th grade 51.6%. The purposes of the internet using were e-mail 40.3%, game 37.5%. 2. In the degree of the internet addiction were 4.5% of addiction, 38.7% of addiction tendency and 56.8% of non-addiction. 3. The score range of the degree of the mental health index of the subjects' were 26-28, mean 47.8. 4. There were significant differences in mental health index(F=34.01, p= .000) to the degree of the internet addiction. 5. There were significant negative correlation between the degree of internet addiction and the mertal health index(r=0.342, p= .000). The result of the study showed the students who are in high-grade in elementary school have already addicted to using of the internet as much as the youth and the more they addicted to the internet, the lower mental health index they have. According to increasing of the using internet among the elementary school students, the internet addiction of them have increased. Therefore, it is necessary to develope a program for prevention and treatment of the internet addiction.

• Research in Community and Public Health Nursing
• /
• v.7 no.2
• /
• pp.216-228
• /
• 1996

The purposes of this study were to investigate levels of physical, cognitive, and social functioning in institutionalized elderly. The subjects were 78 residents of a nursing home for the elderly in Pusan. The data were collected from June 24th to July 8th, 1996 using interview and observational method. The structured questionnaires developed by Kim, by Kwon & Park, and by researcher were adopted to measure physical, cognitive, and social function, respectively. The data were analyzed using percentages, means, t test, ANOVA, Pearson correlation coefficient, Cronbach's alpha with the SPSS PC programs. The results were summarized as follows: 1. 34.2% of the subjects had a paralysis, strokes 26.3%, hearing impairment 15.9%, vision impairment 11.8%, mental disturbance 11.8%, cognitive disturbance 10.5%. 2. The mean score on the physical function for the subjects was 73.14, and the items with low functioning levels were 'ascending the stairs', 'bathing' in that order. There was no significant difference in physical function according to the following demographic characteristics: sex, age, and education level. 3. 50.0% of subjects was categorized 'definite dementia', 'questionable dementia' 11.5%, 'definite non-dementia' 38.5%. There was a significant difference in cognitive function according to sex, but were no significant differences according to following demographic characteristics: age and education level. 4. The mean score on the social function for the subjects was 17.60. The items with comparatively high score were in simple activities such as 'enjoying talking with his friends', 'watching TV or listening to the radio', and the items with low score were in complex activities such as 'enjoying a hobby',. 'enjoying a game', 'reading the newspaper or book'. There were no significant differences in social function according to sex and age, but was a significant difference according to education level. 5. Social function was positively correlated with both physical function and cognitive function.

• The Journal of the Korea Contents Association
• /
• v.18 no.2
• /
• pp.370-377
• /
• 2018

Focus level has been important mental state in user study. Cardiac response has been related to focus and less clarified. The study was to determine cardiac parameters for recognizing focus level. The sixty participants were asked to play shooting game designed to control two focus levels. Electrocardiogram was measured during task. The parameters of time domain and frequency domain were determined from ECG. As a result of independent t-test, RRI, SDNN, rMSSD and pNN50 of time domain indicator were statistically significant in recognizing focus level. LF, HF, lnLF and lnHF of frequency domain were observed to be significant indicator. The rule base for recognition has been developed by the combination of RRI, rMSSD and lnHF. The rule base has been verified from another sixty data samples. The recognition accuracy were 95%. This study proposed significant cardiac indicators for recognizing focus level. The results provides objective measurement of focus in user interaction design in the fields of contents industry and service design.

• Science of Emotion and Sensibility
• /
• v.21 no.3
• /
• pp.73-82
• /
• 2018

Attempts have been made to recognize social emotion, including competition-cooperation, while designing interaction in work places. This study aimed to determine the cardiac response associated with classifying competition-cooperation of social emotion. Sixty students from Sangmyung University participated in the study and were asked to play a pattern game to experience the social emotion associated with competition and cooperation. Electrocardiograms were measured during the task and were analyzed to obtain time domain indicators, such as RRI, SDNN, and pNN50, and frequency domain indicators, such as VLF, LF, HF, VLF/HF, LF/HF, lnVLF, lnLF, lnHF, and lnVLF/lnHF. The significance of classifying social emotions was assessed using an independent t-test. The rule-base for the classification was determined using significant parameters of 30 participants and verified from data obtained from another 30 participants. As a result, 91.67% participants were correctly classified. This study proposes a new method of classifying social emotions of competition and cooperation and provides objective data for designing social interaction.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2009.05a
• /
• pp.187-190
• /
• 2009

A multiple pulse rocket motor distributes the thrust energy more effectively compared to typical rocket motor as providing subsequent thrusts by the pulse motors of the missile. The pulse rocket motor is the advanced technology to improve an end game capability of the missile by increasing the range and final velocity. A pulse separation device is the core part of the pulse motor. The pulse separation device of bulkhead type was designed and developed. The elastic-plastic structural analysis of the bulkhead and rupture disc was conducted. Several air tests were also conducted to confirm the structural safety and acceptability about the design concept. Test results were compared with the analysis results, which showed reasonable agreements.

• Journal of the Korean Dietetic Association
• /
• v.7 no.4
• /
• pp.331-348
• /
• 2001

The purpose of this study was to obtain basic data for nutrition education of the children in a health promoting elementry school. The data was collected by a questionaire of food habits, and anthropometric measurement and biochemical test in comparison with obesity index. The study subjects were boys and girls aged 10 to 12 years who participated in the “99 Children Nutrition Camp”. The average obesity index was 1.7$\pm$21.6% in boys and -11.4$\pm$12.6% in girls. After school, major leisure items were significnatly different by gender but both boys and girls played mainly computer game. In concern for body image and eating habits, girls had more concern and girls had attempted weight control more than boys. 80.2% of subjects had prejudice for special food, especially, all subjects in the severely underweight group had prejudice. But this tendency was significantly decreased with the increasing obesity index. The lowest preferency was for vegetables(64.4%). The tendency of prejudice of subjects was higher whose mother are thirties than those of subjects whose mother are in fourties. The serum GOT and GPT values were significantly higher in overweight and obese group than the other groups. The only serum T-chol was significantly higher in boys than in girls. The number of risk factors related to coronary heart disease(CHD) based on coresponding criteria of TG, T-chol, HDL-chol, and LDL-chol was not increased significantly with the degree of obesity index. The results indicated the need of nutritional management for the children. At a point of view, to educate children early who are able to change food habits and life-styles means to help heathy growth and to deliver up heathy adults. Active nutrition education for both children and mothers will be recommended with joint participation of nutritionists in community public health center and elementary school.

• The Korean Journal of Air & Space Law and Policy
• /
• v.14
• /
• pp.151-174
• /
• 2001

Theories of international organization have explained the creation, maintenance, and decline of international organization. However, their explanations on changes of international organization have been much more different one another. For example, the theory of hegemonic stability argues that international organization can be created and maintained only by a hegemonic state and will be declined if the hegemonic state decline. On the other hand, the functional approach believes that the positive functions and effects that international organization provides motivate states to create and maintain the organization, while the game-theoretical approach explains international organization based on cost-benefit calculation of rational states. Thus, the empirical evaluation of the arguments of the theories of international organization and defining the major factors that determine international organization are necessary not only for the development of theories of international organization but also for making desirable policies toward international organization. For the purpose, this paper compares and contrasts the three major theories of international organization and applies the approaches to the case of the International Civil Aviation Organization (ICAO) to test their arguments. Since the ICAO has been rarely examined by the theories of international organization, the case study could be desirable case to evaluate theories of international organization. In this sense, this paper attempts to define the major factors that determine the creation, maintenance, and decline of the ICAO. In particular, since the Korean government has changed its policy for air transport security system recently, it will investigate the role of ICAO on the policy change to define the limits and strength of ICAO. In conclusion, this paper will assess the relative explanatory power of each approach based on the analysis of the creation and changes of ICAO

• Physical Therapy Korea
• /
• v.20 no.3
• /
• pp.19-26
• /
• 2013

The smart-phone has become a necessity for most people. In this study, we determined that using a smart-phone for 20 minutes can cause increased neck and shoulder muscle activities and fatigue. Seventeen healthy male smart-phone users who attended Yonsei University played a smart-phone game for 20 minutes and changes in their bilateral cervical erector spinae and upper trapezius muscle activities and fatigue were measured. To assess muscle activities and fatigue, we used the following variables: the median frequency, the 50th percentile Amplitude probability distribution function (APDF) value (median load), and the discrepancy in the 90th percentile APDF value and the 10th percentile APDF value (APDF range). A paired t-test was used to compare pre-smart-phone-use status with post-smart-phone-use-status. The median frequency of the bilateral cervical erector spinae and the upper trapezius decreased significantly after 20 minutes of smart-phone use (p<.05). In addition, the 50th percentile APDF value of the bilateral cervical erector spinae and the right upper trapezius increased significantly (p<.05). The APDF range of the bilateral cervical erector spinae and the upper trapezius also increased significantly (p<.05). However, the 50th percentile APDF range of the left upper trapezius was not significantly different (p>.05). These findings suggest that using smart-phones for 20 minutes can induce muscle fatigue and increased neck and shoulder muscle activities.