• Journal of the korean society of oceanography
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• 제34권1호
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• pp.1-21
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• 1999

A two-layer quasi-geostrophic numerical model is used to investigate the temporal variability of the East Korea Warm Current (EKWC), especially the separation from the Korean coast and the generation of warm eddies. An attention is given on the active role of the nonlinear boundary layer process. For this, an idealized flat bottom model of the East Sea is forced with the annual mean wind curl and with the inflow-outflow specified at the Korea (Tsushima) and Tsugaru Straits. Two types of separation mechanisms are identified. The first one is influenced by the westward movement of the recirculating leg of the EKWC (externally driven separation),the second one is solely driven by the boundary layer dynamics (internally driven separation). However, these two processes are not independent, and usually coexist. It is hypothesized that 'internally driven separation' arises as the result of relative vorticity production at the wall, its subsequent advection via the EKWC, and its accumulation up to a critical level characterized by the separation of the boundary flow from the coast. It is found that the sharp southeastern corner of the Korean peninsula provides a favorable condition for the accumulation of relative vorticity. The separation of the EKWC usually accompanies the generation of a warm eddy with a diameter of about 120 km. The warm eddy has a typical layer-averaged velocity of 0.3 m/s and its lifespan is up to a year. In general, the characteristics of the simulated warm eddy are compatible with observations. A conclusion is therefore drawn that the variability of the EKWC is at least partially self-excited, not being influenced by any sources of perturbation in the forcing field, and that the likely source of the variability is the barotropic instability although the extent of contribution from the baroclinic instability remains unknown. The effects of the seasonal wind curl and inflow-outflow strength are also investigated.

• Physical Therapy Rehabilitation Science
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• 제2권2호
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• pp.115-118
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• 2013

Objective: Whole body vibration training is a relatively new approach for enhancement of muscle strength, physical performance, and balance. The aim of this study was to assess the effect of unilateral whole body vibration training. Design: One group pretest-posttest design. Methods: Sixteen healthy, physically active volunteers participated in this study. Whole body vibration was applied with a frequency of 20 Hz and an amplitude of 3 mm for 3 minutes. Muscle performance and static balance were assessed before and after unilateral whole body vibration training. One leg standing broad jump test was measured to determine muscle performance which is closely linked to lower extremity muscle function. The good balance system was used in evaluation static balance. All test were measured 3 times and the average value was analyzed. Results: Jumping length was significantly improved by 0.11m in all participants after intervention (p<0.05). Among static parameters, significant results were observed where in the eyes opened condition, X-speed (medial-lateral sway) changed from 4.20 mm/s to 4.95 mm/s, Y-speed (anterior-posterior sway) changed from 5.77 mm/s to 6.54 mm/s and velocity moment changed from $12.77mm^2/s$ to $13.57mm^2/s$ (p<0.05). In the eyes closed condition, X-speed changed from 4.34 mm/s to 4.85 mm/s, Y-speed changed from 7.84 mm/s to 8.16 mm/s and velocity moment changed from $16.03mm^2/s$ to $16.11mm^2/s$ (p<0.05). Conclusions: Immediate unilateral whole body vibration improved muscle performance but impaired static balance in young adults.

• 대한물리의학회지
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• 제12권3호
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• pp.99-104
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• 2017

PURPOSE: Gait disturbances in patients with hemiplegic stroke involve asymmetry of stance time. Step box training is used to supplement the limitations of stair walking training and increasing the torque value of the paralyzed lower leg's strength. This study aimed to investigate whether step-up training on unstable support could change walking ability in patients with chronic stroke. METHODS: Thirty stroke patients were randomly assigned to the step-up training group (experimental group), that performed training on an unstable surface, and the control group, that performed training on a stable surface. Walking speed, step length, and cadence were measured before and after training. Paired t-tests were used to compare pre- and post-intervention data, while the independent samples t-test was used to determine intergroup differences. Values of p < .05 were considered statistically significant. RESULTS: There was a significant difference in walking ability before versus after the intervention in both groups, although the experimental group showed greater differences than the control group (walking velocity by 8.1%; step length of the non-paralyzed side by 6.9%, respectively; p<.05). CONCLUSION: Step-up training might be more effective on an unstable surface than on a stable surface for increasing walking speed and step length of the non-paralyzed side.

• 대한물리치료과학회지
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• 제12권4호
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• pp.25-31
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• 2005

이 사례연구는 2002년 10월 15일 칼에 의한 좌상으로 경추 3-4번의 불완전 척수손상을 입은 25세의 남자 환자가 최초 병원에서 2002년 12월 한달 간의 치료를 마친 후, 2003년 1월 3일부터 4월 28일까지 태릉에 위치한 N 재활센터에서 주 5회 2시간의 자세조절 훈련, 심폐지구력 훈련, 웨이트 훈련, 스포츠(축구, 소프트 볼), 여가활동(등산)의 프로그램을 적용하여 척추손상 환자의 사회적응을 돕기위한 재활 프로그램의 다양화를 꾀하기 위한 기초 선행 작업으로 시작되었다. 신체능력을 평가하기 위한 측정도구는 관절가동범위(Range of Motion), 수동근력검사(Muscle Manual Test), 경직(Spasticity), 신체체력(Physical Fitness), 발란스(Balance: one leg stand), 상대적인 등속성 하지근력(Isokinetic Muscle Strength) 그리고 신체조성(Body Composition)로 하였다. 재활기간을 통해 처음 시작 일자에서 45일 간격으로 3차례의 측정을(1월 3일부터 4월 28일까지 실시하였다) 실시하였다. 최초 환자의 상태는 부분적으로 일상생활의 도움을 받아야 하는 상태로 동작을 시작하려 할 때 경직이 발생되어 옷을 입고 벗기, 신발 신고 벗기, 운전, 식사, 보행과 계단보행, 경사보행에서 보조자의 도움이 필요했으며, 작은 물건 잡기와 글씨쓰기, 타이핑 작업은 불가능 한 상태였다. 또한 스포츠 활동과 여가활동 역시 불가능 한 상태였다. 3달 15일간의 기간 동안 환자는 복학을 준비하기 위해 적극적으로 치료에 임했으며, 결과는 다음과 같았다. 신체조성은 재활 훈련을 통해 체중, 체지방율(%), 복부지방율(WHR)의 많은 감소를 가져왔다. 경직을 측정하는 Ashworth Scale은 정상에 가깝게 감소하였다. 관절가동범위는 고관절, 무릎, 발목에서 모두 증가하였다. 수동근력검사(0-9)는 많은 향상을 가져왔다. 신체체력능력 항목에서 근지구력의 윗몸일으키기와 팔굽히기, 악근력, 유연성으로 앉아 체간 숙이기, 민첩성으로 사이드 스텝, 순발력의 서전트는 모두 크게 향상되었다. 환자의 일상능력에서도 옷을 입고 벗기, 신발 신고 벗기, 운전, 식사, 보행과 계단보행, 경사보행에서 보조자의 도움이 필요없었으며, 타이핑 작업은 5손가락을 모두 사용하지는 않았지만, 1분에 80타로 큰 향상을 가져왔다. 또한 축구와 소프트볼, 등산을 달에 1회 정도 실시하여 약간의 도움만으로 가능하게 되었다.

• 근관절건강학회지
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• 제24권3호
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• pp.217-226
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• 2017

Purpose: The aim of this study was to identify the effects of Tai Chi training program on physical fitness, stress response and ego-resiliency in nursing students. Methods: 28 nursing students of D metropolitan city participated in non-equivalent control group pre- and post-test group test in quasi experimental design with written consent. Fourteen participants in the control group who did usual activities and 14 experimental participants who promised to participate 24 Tai Chi training sessions for 12 weeks. Both groups completed pre- and post-test measurement for physical fitness, a questionnaire regarding their stress response and ego-resiliency. Each 60-minute Tai Chi session was consisted of 5-minute warm up, 10-minute meditation, 40-minute Tai Chi, and 5-minute finishing exercise. Results: After 12 weeks, participants in the Tai Chi group reported significantly higher score in muscle endurance (t=3.77, p=.001), leg muscular strength (t=2.14, p=.042), and balance (t=2.12, p=.044) compared to the control group. The Tai Chi group recorded significantly lower score than the control group on stress response (t=2.75, p=.011). Conclusion: The findings highlight the importance of Tai Chi for a reduction in stress response and promotion in physical fitness in nursing students. Applying Tai Chi training to nursing program will help nursing students to have better academic performance.

• Annals of Clinical Neurophysiology
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• 제4권1호
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• pp.44-50
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• 2002

Introduction : Orthostatic tremor develops in the legs while standing up with no weakness, pain or imbalance in the leg and the tremor is characteristically not observed when walking. However there have been some confusions about orthostatic tremor in several aspects. For the past ten years, we have observed 4 patients with orthostatic tremor. In each case tests were performed to investigate the following three important areas of inquiry about orthostatic tremor. Firstly, whether this disorder is an independent diagnostic entity or a variant of essential tremor. Secondly, whether the progress of this disorder is specifically related with standing posture. Lastly, the nature of the pathophysiologic mechanism behind the appearance of the tremor when standing after the lapse of a certain latent period and its disappearance upon the commencement of walking. Methods : Our 4 cases of orthostatic tremor were studied clinically, electrophysiologically, and pharmacologically. Electrophysiological tests included tremor spectrum test and electromyography. Results : We observed the presence of this tremor in several other tonic postures, as well as its absence, in a vertically lifted position from all our cases. Our cases registered a variable tremor frequency between 5 and 12 Hz according to the tremor spectrum test and EMG. Furthermore all our 4 cases demonstrated patterns of both synchronous EMG activity and alternating EMG activity at various times in homologous muscles of both legs. Orthostatic tremor was improved significantly with propranolol as well as clonazepam. Conclusions : From the results of our study we drew the following conclusions. It is probable that orthostatic tremor is simply a variant of essential tremor rather than being an independent diagnostic entity and that in most cases its development is specifically related with muscle contraction rather than merely with the act of standing. Furthermore we discovered a clue in the previously described neural control mechanism that the nuclear bag fibers in the muscle spindle have lag time of several seconds in their response to muscle strength and that their baseline does not reset fully in rapidly moving muscle. This neural control mechanism could offer sufficient explanation for the phenomena of tremor appearance when standing and disappearance when walking in orthostatic tremor.

• Steel and Composite Structures
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• 제35권3호
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• pp.305-325
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• 2020

Beams of steel frame-tube structures (SFTSs) typically have span-to-depth ratios of less than five. This makes a flexural beam unsuitable for such an application because the plastic hinges at the beam-ends cannot be adequately developed. This leads to lower ductility and energy dissipation capacities of SFTSs. To address this, SFTSs with bolted web-connected replaceable shear links (SFTS-BWSLs) are proposed. In this structural system, a web-connected replaceable shear link with a back-to-back double channel section is placed at the mid-length of the deep beam to act as a ductile fuse. This allows energy from earthquakes to be dissipated through link shear deformation. SFTS and SFTS-BWSL buildings were examined in this study. Several sub-structures were selected from each designed building and finite element models were established to study their respective hysteretic performance. The seismic behavior of each designed building was observed through static and dynamic analyses. The results indicate that the SFTS-BWSL and SFTS have similar initial lateral stiffness and shear leg properties. The SFTS-BWSL had lower strength, but higher ductility and energy dissipation capacities. Compared to the SFTS, the SFTS-BWSL had lower interstory drift, base shear force, and story shear force during earthquakes. This design approach could concentrate plasticity on the shear link while maintaining the residual interstory drift at less than 0.5%. The SFTS-BWSL is a reliable resistant system that can be repaired by replacing shear links damaged due to earthquakes.

• 한국의류학회지
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• 제41권3호
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• pp.537-547
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• 2017

This study evaluates the wearing performance of a self-contained breathing apparatus (SCBA) belt for firefighters in Korea. A SCBA belt design was suggested based on the wearing evaluation of a SCBA belt; subsequently, prototypes I and II were created. A wearing evaluation of prototypes with improved design and design preference was performed. Six designs elements of the SCBA belt for firefighters were suggested based on the survey results of wearing the SCBA belt and for the SCBA belt design preference for use by firefighters. First, belt material should be made of black high-strength aramid textiles. In addition, Velcro should be used to attach and detach retroreflective and fluorescent materials along with various colors for visibility. Second, the chest belt should be made of the same material used for other parts; in addition, the chest belt should be moved to the center for center of gravity and a cobra buckle should be applied. Third, an O-ring should be applied to the back and the belt connected to the O-ring should distribute the weight in six axes. Fourth, a detachable air respirator should be able to separate by using upper and lower cobra buckles. Fifth, a separable leg belt and a detachable pocket are also suggested. Sixth, a ring for walkie-talkies, alarms and equipment as a fabric ring are also suggested. Prototype III with an improved design was created based on the results of the design suggestion.

• 대한족부족관절학회지
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• 제13권1호
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• pp.34-39
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• 2009

Purpose: We try to evaluate the clinical results of the acute Achilles tendon rupture treated with Krackow suture technique. Materials and Methods: We reviewed 27 patients with acute Achilles tendon rupture treated between October 2005 and September 2007. There were 26 complete ruptures and 1 incomplete rupture. All were ruptured at tendinous area. There were 21 men and 6 women, and mean age was 38 years. We repaired ruptured Achilles tendon with Krackow suture technique. The results were evaluated with Arner-Lindholm scale for patients' satisfaction, strength of calf muscle power, calf circumference, and ankle motion. The average follow-up was 29 months. Results: The patients' subjective clinical results was excellent in 25 cases and good in 2 cases. There were 15 cases of less than 1 cm, 6 cases of 1${\sim}$3 cm, and 1 case of more than 3 cm in the calf circumference difference between the normal and affected leg. There were 20 cases of less than 5 degrees, and 2 cases of more 5 degrees in the difference of range of motion between the normal and affected ankle. We had an experience of postoperative deep infection in one diabetic patient. Conclusion: We had a good clinical result for acute Achilles tendon rupture treated with Krackow suture method. So we recommand Krackow suture technique for acute Achilles tendon rupture.

• 한국운동역학회지
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• 제26권3호
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• pp.323-331
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• 2016

Objective: The aims of this study were 1) to develop easy-to-use rhythmic balance training equipment for the elderly and 2) to investigate the effect of training with the equipment on balance and physical function. Method: Twenty-one elderly individuals (age: $75.4{\pm}3.34yrs$, height: $152.07{\pm}4.81cm$, weight: $58.35{\pm}8.34kg$) participated in this study. Each participant underwent balance and physical function testing before and after 12 weeks of training with the equipment. Y-balance (i.e. dynamic balance) and one leg static balance tests were used for balance testing, and timed up- and-down-stairs and five times sit-to-stand tests were used for physical function testing. A paired t test was used to determine whether there was a significant pre- and post-training difference. Results: The rhythmic balance training equipment provided a fun and motivating training program with age-friendly music, dance movements for lower extremity strength training, and touch screen controls with simple features. Post-training left foot dynamic balance was significantly greater (p<.05), and static balance with eyes open was significantly improved (p<.05) compared to pre-training. Completion of the timed up-and-down-stairs and the five times sit-to-stand tests was significantly shorter (p<.05) compared to pre-training. Conclusion: Training using the equipment developed in this study improved balance and physical function in elderly participants.