• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.167-174
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• 2020

The purpose of this study was to investigate the kinematic comparison between successful and failed trials of Lopez vault techniques in male gymnastics. The subject, an Olympic gold medalist, was YHS (age: 27 years, height: 1.6 m, and mass: 53 kg) and fourteen high speed motion capturing cameras were used for data collection. The 26 reflective sensors were attached on major anatomical positions and 15 segment-body model was used to calculate the kinematic variables. According to results, the contact duration of the spring-board for successful trial(ST) was longer and that of failed trial(FT) and the range of motion of knee joint for ST was greater than that of FT. The movement times during pre-flight between ST and FT were same, but the movement time of horse contact period for ST was shorter than that of FT. The ST showed a longer movement time during post-flight and the longer horizontal distance than those of FT. Conclusively, YHS needs to approach the horse with a higher position of the body and higher incidence angle, as well as make faster twist angular velocity in an attempt to achieve ST.

• Korean Journal of Applied Biomechanics
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• v.17 no.1
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• pp.191-199
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• 2007

This study was conducted to examine the biomechanical characteristics of open spike in the volleyball to improve the technique of the volleyball spike. The subjects were six male college and high school athletes. The motions of volleyball spike were filmed by using two Sony VX 2000 Video Cameras. The mechanical factors were angle and angular velocity of body segments in the upper and the lower limbs. The conclusions were as follows; 1. The angle of the shoulder joint of the skilled showed larger than that of the unskilled in impacting of the volley ball spike. 2. The angle of the elbow joint of the skilled showed larger than that of the unskilled in impacting of the volley ball spike. 3. The angle of the wrist joint of the skilled showed smaller than that of the unskilled in impacting of the volley ball spike. 4. The angle of the hip joint of skilled showed larger than that of unskilled in impacting of the volley ball spike. 5. The angle of the knee joint of the skilled and the unskilled showed same in take off and impacting of the volley ball spike, and that of the skilled showed smaller than that of the unskilled in take-off touchdown and touchdown after impact of the volley ball spike. 6. The angle of the ankle joint of skilled showed larger than unskilled in take-off of the volley ball spike. 7. The angular velocity of the shoulder joint, elbow joint, wrist joint of the skilled showed faster than that of the unskilled in impacting of the volley ball spike. Taken together the result of them, I have come to conclusion that knee joint angle in touchdown of the take off should be decreased and knee joint angle in take off should be increased, and then stability of the take off should be made and, and that extension of the elbow joint should be made and wrist joint angle decreased and shoulder and hip joint angle increased, and then C.O.G of the arm and hand should be positioned ahead C.O.G of the body in impacting for effective impact of the spike, and that the transfer of the angular velocity of body segments for effective impact of the spike make from the proximal segment to the distal segment at spike in volleyball.

• Korean Journal of Applied Biomechanics
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• v.18 no.3
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• pp.61-69
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• 2008

The purpose of this study is to examine the success or failure on the balance beam in element group requirements posture which is bending salto side-ward tucked through kinetic analysis. The national team players were participated. The goal was to present training methods to coaches and athletes so as to provide scientifically useful information. The results from this study were summarized as below. When the performance was successful, the features of the body's center of gravity during the side somersault motion showed to spread from the center of the balance beam and the center of the gravity moved to the direction of the body's rotation. In the spring sections - event2 and 3, when the performance was successful, up/down fluctuation became more wider and increased air time. It supported the result that the projecting variable was higher than in failure trial. In addition, the right side hip joint angles and speed, and angular velocity as jumping up for a leap were larger than in failure trial. Those variables showed the optimal conditions for a leap. By increasing the speed of the upper limb from the shoulder and the speed of the shoulder joint angular velocity, the momentum was increased. Especially the right side shoulder joint angular velocity increased dramatically because the right leg was held. As to the side somersault motion, the angular momentum of successful trial with respect to x-axis was bigger than failed trial. It indicated that the increasing angular momentum with respect to x-axis was an important factor in flying motion. Besides, as to side somersault, the appropriate proportion of angular momentum with respect to y-axis and z-axis was a key to successful trails.

• Sleep Medicine and Psychophysiology
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• v.18 no.2
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• pp.76-81
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• 2011

Objectives: This study aims to analyze the association between the severity of sleep apnea, sleep and mood related scales, and activity during sleep in obstructive sleep apnea syndrome (OSAS) patients. Methods: 176 drug-free male patients confirmed as OSAS (average age=$43{\pm}11$ years) were selected through nocturnal polysomnography (NPSG). OSAS was diagnosed with apnea-hypopnea index (AHI) >5, mean AHI was $39.6{\pm}26.0$. Sleep related scales were Stanford Sleepiness Scale (SSS), Epworth Sleepiness Scale (ESS), Pittsburg Sleep Quality Index (PSQI) and Morningness-Eveningness Scale (MES). Mood related scales were Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), State-Trait Anxiety Inventory (STAI) I, II and Profile of Mood States (POMS). NPSG was performed overnight with both wrist actigraphy (WATG). Parameters produced from WATG were total activity score, mean activity score and fragmentation index. We analyzed the correlation between each scale, AHI scored from NPSG and activity score analyzed from WATG. Results: ESS showed significant positive correlation with PSQI, BDI, BAI and STAI I, II, respectively (p<0.01). SSS showed significant positive correlation with PSQI and BAI (p<0.05, p<0.01). BAI showed significant positive correlation with total activity score, mean activity score and fragmentation index (p<0.05, p<0.01, p<0.05).Total activity score showed significant positive correlation with ESS and BAI, respectively (p<0.05). Fragmentation index showed significant positive correlation with ESS, PSQI and BAI (p<0.05, p<0.01, p<0.05). AHI, indicator of sleep apnea is showed no significant correlation with each sleep and mood related scale. Conclusion: The degree of daytime sleepiness tends to be associated with night sleep satisfaction, depression and anxiety, and the activity during sleep rather than the severity of sleep apnea.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.17-32
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• 2002

The purpose of this study was to find the rational method to analyze golf swing with specific property of club shaft. Three subjects were filmed by two high speed digital cameras with 500 fps. The phase analyzed was downswing of each subject. The three-dimensional coordinates of the anatomical landmarks were obtained with motion analysis system Kwon3d 3.0 version and smoothed by lowpass digital filter with cutoff frequency 6Hz. From these data, kinematic and kinetic variables were calculated using Matlab(ver 5.0) The variables for this study were angular velocity and accelerations, which were calculated and following conclusions have been made : 1) Golf swing time of stiff club is faster than that of regular club. 2) In shoulder joint motion of swing with the stiff club, x-stiff showed mort rapid negative acceleration than that of regular club. 3) In regular club, the velocity of club head would be more effective velocity, which was increasing, than those of other clubs before impact. 4) In wrist joint motion of swing with stiff club, x-stiff club showed faster than regular club in the downswing and impact more rapid negative acceleration.

• Childhood Kidney Diseases
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• v.6 no.1
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• pp.61-67
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• 2002

Purpose: The urinary mass screening program in school aged population has been performed since 1981, but the consensus on the follow-up schedule and the management of isolated proteinuria has not been reached yet. The aim of this study was to investigate the cause of isolated proteinuria and to propose a guideline for the treatment and follow-up afterwards Methods: The medical records of 114 cases of isolated proteinuria detected through the analysis of urinary mass screening and evaluated at the pediatric outpatient clinic of Asan Medical Center from January 1990 to July 2001 have been reviewed. Results: The classification of isolated proteinuria was as follows. Transient proteinuria $32\%$, orthostatic proteinuria $65\%$, persistent proteinuria $3\%$, In orthostatic proteinuria group, daytime and nighttime proteinuria were $319.2{\pm}189.1\;mg/dL$ and $56.5{\pm}56.1\;mg/dL$. In persistent proteinuria group, daytime and nighttime proteinuria were $1140{\pm}540.5\;mg/dL$ and $289{\pm}58\;mg/dL$. After 30 month follow-up, 2 cases of persistent proteinuria were needed renal biopsy and 1 case revealed focal segmental glomerular sclerosis. In all cases, serum creatinine, albumin and complements levels were normal. In the orthostatic proteinuria group, no significant renal diseases were detected. Conclusion: Since most of the isolated proteinuria detected through the school urinary mass screening were orthostatic proteinuria or transient proteinuria, initially aggressive diagnostic method such as renal biopsy is not needed and regular follow- up with quantitation of proteinuria is warranted.(J Korean Soc Pediatr Nephrol 2002 ; 6 61-7)

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.79-88
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• 2014

Vampilov, who is not well known as a playwright in domestic, is acknowledged comparable to Anton Chekhov in Russia. This paper was planed in order to promote a unsatisfied study until now in domestic for works by Vampilov and studied a part of composing play to put on the stage for , a drama written by Vampilov. This paper, originated from a viewpoint that actor have to complete the final text of the play for audiences to read depending on the drama and based on work features and characters of Vampilov, established an analysis scheme according to segments of unit actions for actions of Sarafanov, the character of the play, in order to achieve a purpose under suggested situation at the drama and focused on completing purposes per units individually. We have analyzed Sarafanov and his actions referring patterns and probabilities of the characters in the other works by Vampiov and regarded it as the important item together with logical basis of actions. Lyric and humanism emphasizing works by Vampilov, affected by Anton Chekhov and Nikolai Vasilevich Gogol, are acknowledged as realistic descriptions using contingency and a play within a play outstandingly and emphasized an importance of human relation. We have selected as a primary way to compose action text that audiences would read on the stage and used it as the method to design action of the characters in order to activate natural good of Sarafanov and general absurdities that human, does creative works, never give up purposes of ideal life.

• Journal of Veterinary Clinics
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• v.31 no.5
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• pp.449-453
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• 2014

A 2-year-old, intact male, Persian exotic cat, weighing 2 kg with a history of a palpated abdominal mass was admitted to Veterinary Medical Teaching Hospital, Seoul National University. On routine complete blood count (CBC) and serum biochemical analyses, there were anemia and 0.45 of albumin to globulin ratio. A feline infectious peritonitis (FIP) virus antibody test kit was negative. Radiography, ultrasonography and computed tomography (CT) were performed. A markedly enlarged abdominal mass was found. On cytologic examination of this mass, it was diagnosed as alimentary lymphoma or pyogranulomatous inflammation. Chemotherapeutic treatment for intestinal lymphoma was provided for several weeks, but the mass size was increased and clinical signs were not improved. The cat died six days after discontinuing chemotherapy. On postmortem examination, the definitive diagnosis was FIP. This case describes a cat with FIP in which an abdominal tumor had been suspected clinically.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.345-359
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• 2002

The purpose of the study was to provide the fundamental data to instruct athletes through the analysis athletes' movement in javelin. Three athletes in the level of national representative were participated in this study. The study analyzed kinematic variables(lead foot and releasing javelin) through 3-D analysis and obtained the following results. 1. During withdrawal, it is important to maintain of running horizontal velocity. 2. It was showed that throng average height was $84{\pm}3.3%$ and javelin adequative degree, Among the athletes, $S_2$ who had the best record was released the javelin with the fast velocity, but throw the javelin with the less releasing velocity. 3. $S_2$ released after lead foot were completely landed and therefore it is no problem in a kinematic aspect. However, $S_1$ angle was too small. it caused increase of release velocity to be prevented. 4. $S_2$ showing the best result indicated shorter in duration time. Generally, the shorter duration time in release phase showed the longer release distance. Especially $S_1$ and $S_3$ showing the worse result indicated the longer duration time in preparatory phase, causing the breakup of force. Therefore to improve the record, it should be decreased the duration time in preparatory phase. 5. Compared with $S_1$ and $S_3$, $S_2$ showing the best record indicated the higher velocity in center of mass, trunk, upper arm, lower arm and hand That is the higher velocity of upper arm at release leaded the better velocity transfer from upper arm to following lower arm and hand, these action should be considered to be helpful of better record. According to the above conclusion, when the athletic leaders cauch athletes, they should focus on maintaining knee angle, upper body and hip angle in a previous stage of release and throwing angle, throwing height, throwing velocity in a release stage.

• Archives of design research
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• v.19 no.5 s.67
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• pp.129-138
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• 2006

It is expected that the typical lifestyle of the future will be transformed into an opulent and comfortable existence as the quality of life improves due to the increase in household income and reduction in working hours. In the meantime, as the standard of living becomes increasingly more comfortable and plentiful, the toll on physical health becomes magnified as a result of obesity and insufficient exercise caused by super nutrition and change in labor conditions (from physical labor to mental labor). This has instigated a deep awareness in fitness on the part of many people, forcing them to recognize the significance of daily exercise and physical activity. The high annual growth rate in the fitness and athletic apparatus market, which is more than 20%, is attributed to this phenomenon. The Elliptical Cross Trainer(ECT), which has drawn wide attention recently, is a non-impact athletic apparatus that not only promotes exercise of the upper body parts in such sports as skiing but also the exercise of lower parts of the body on a treadmill. It is a type of cross training athletic gear that has been developed for aerobic exercise throughout the entire body. It has already formed a market as big as that of the treadmill in Europe, America, etc. Recently, its demand is growing sharply in the Korean markets as well as those in Northeast Asian countries, Despite such demand increase and expansion, since most of the expensive ECTs are exclusively supplied by suppliers in only a few advanced countries, localization of the ECT is urgently required in order to enhance competitiveness of Korean manufacturers and to expand the market. This paper introduces the process and results of a design-engineering cooperative study that was peformed for the development of the ECT.