• Computers and Concrete
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• 제18권2호
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• pp.179-199
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• 2016

The aim of this study is to investigate arrival direction effects of travelling waves on non-linear seismic response of arch dams. It is evident that the seismic waves may reach on the dam site from any direction. Therefore, this study considers the seismic waves arrive to the dam site with different angles, ${\theta}=0^{\circ}$, $15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, $75^{\circ}$, and $90^{\circ}$ for non-linear analysis of arch dam-water-foundation interaction system. The N-S, E-W and vertical component of the Erzincan earthquake, on March 13, 1992, is used as the ground motion. Dam-water-foundation interaction is defined by Lagrangian approach in which a step-by-step integration technique is employed. The stress-strain behavior of the dam concrete is idealized using three-dimensional Drucker-Prager model based on associated flow rule assumption. The program NONSAP is employed in response calculations. The time-history of crest displacements and stresses of the dam are presented. The results obtained from non-linear analyses are compared with that of linear analyses.

• 종양간호연구
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• 제2권1호
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• pp.17-26
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• 2002

Purpose: This study was conducted to evaluate the effects of aerobic dance on physical functionnings of women with mastectomy. The study was single group pre- & post-test time series design. The aerobic dance program was performed three times a week for eight weeks, 45${\sim}$60 minutes per session. Method: The research variables used in the study were the period(seconds) of exercise that was taken for target heart rate, activity systolic pressure, range of motion of shoulder joint in affected side, and flexibility for physical functionnings. The data were analyzed with repeated measure ANOVA and Bonferroni multiple comparisons. Results: Over the period of aerobic dance, the degree of all the research variables were changed significantly, and also differed significantly every 2 to 4 weeks. The period(seconds) of exercise that was taken for target heart rate (p <.000), systolic pressure in exercise(p =.019), range of motions of shoulder joint on the affected side(flexion, abduction, over-adduction, over-extension, external & internal rotation), and flexibility(sit & reach, back & reach) (p= .003; p=.001; p(.001; p<.001; p= .014; p<.001; p=.036; p<.001) were differed significantly respectively. Conclusion: The results suggest that the aerobic dance program for women with mastectomy can improve and recover cardiopulmonary endurance and ROM of shoulder joint and that the period of exercise had to be performed over six to eight weeks and three times a week at least.

• 한국항해학회지
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• 제10권2호
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• pp.97-114
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• 1986

Ship's maneuverability is very important factor in safe ship handling and economical ship operation. Steering characteristics are consisted of course stability and maneuverability. Today in many advanced ship-building countries, they study ship's course stability, using model ship tests, such as straight line tests, rotating arm tests and Planar Motion Mechanism (PMM) etc., in tow in tanks. It is the purpose of this paper to provide ship's handlers with better understanding of steering characteristics and to help them in safe controlling and manevering . In this paper, the author simulated response of various vessels, running straight course with constant speed, and they are disturbed by small external disturbance of one degree yaw angle with no angular velocity . The author used the hydrodynamic derivtives resulted at tests of Davidson's laboratory in Stevens Institute of Technology, New Jersey, U.S.A. Course stability was evaluated and analyzed in various respects, such as block coefficient, ratio of ship's length to beam, draft and rudder area ratio etc. The obtained results are as follows : (1) The ship's course stability is affected by magnitude of block coefficient greatly. In case that the block coefficient is more than 0.7, the deviation varies at nearly same rate but the requistite time to reach the steady course is different. (2) The ship's course stability is affected by magnitude of L/B. When the dimensionless time reaches about 3, the deviation and requisite time to reach the steady course are influenced nearly same. After the dimensionless time is about 3, they change on invariable ratio. (3) The effect to course stability by L/T and RA' can be neglected. (4) The reason why thy VLCC and container feeder vessel are unstable on their course is that their block coefficient is generally more than 0.8 and the ratio of ship's length to beam is about 6.0.

• 대한통합의학회지
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• 제11권2호
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• pp.159-168
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• 2023

Purpose : This study aimed to investigate how neuromuscular electrical stimulation (NMES) affects the balance ability of patients who have undergone total knee arthroplasty owing to osteoarthritis. Methods : Thirty patients who had undergone total knee arthroplasty were randomized to an experimental group (n=15) and a control group (n=15). The experimental group received conventional physical therapy for 50 minutes and NMES treatment for 30 minutes, whereas the control group received conventional physical therapy for 50 minutes and active range of motion (AROM) exercises for 30 minutes. Within-group and between-group changes in static and dynamic balance ability before and after the 4-week intervention were analyzed. Results : In the within-group comparison, sway velocity in the center of gravity and total distance were significantly improved in both the experimental and control groups (p<.05), with no significant differences between the groups (p>.05). In the within-group comparison, both the experimental and control groups showed significant improvement in the functional reach test and movement velosity (p<.05). In the between-group comparison, the experimental group showed a significantly better improvement than the control group in the functional reach test (p<.05), but there was no significant difference in the movement velosity test (p>.05). Conclusion : In this study, NMES improved the static and dynamic balance in patients who had undergone total knee arthroplasty. Compared with AROM exercises, there was a greater effect on dynamic balance partially; however, the overall effect was similar. Therefore, NMES may be one option among various interventions to improve the balance ability in patients who have undergone total knee arthroplasty. In particular, this method may be effective when it is difficult to apply balance training for patients with total knee arthroplasty in a clinical setting.

• 해양환경안전학회지
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• 제21권5호
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• pp.552-557
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• 2015

본 연구에서는 선미형상을 고려한 조종성능을 심수역 뿐만 아니라 천수역에 대해서 수치 시뮬레이션을 통해 검토하였다. 선미형상을 나타내는 파라메터 중 $C_{wa}$를 미소(${\pm}2%$)하게 변화시킴으로써 각 수역에서의 침로안정성, 선회 및 지그재그 성능이 어떤 변화를 보이고 그 경향이 어떻게 변화하는 지를 검토하였다. 선박의 조종성능 관점에서 흘수 대 수심의 비(=d/H)가 0.5 부근에서의 조종성에 큰 변화를 가져오는 중요 지점임을 알 수 있었고, 비대선(VLCC, 탱커 등)과 세장선(컨테이너)의 경우 선미형상의 변화에 따라 조종성능의 변화 정도가 많은 차이를 가질 수 있음을 알 수 있었다. 또한, $C_{wa}$를 감소(U형에 근접)시키면 선회운동에 있어서 advance 및 tactical diameter가 증가하고, 지그재그 운동에서는 track reach는 증가하지만 각 overshoot angle들은 감소한다. 이와 반대로, $C_{wa}$를 증가(V형에 근접)시키면 선회운동에 있어서 advance 및 tactical diameter는 감소, 지그재그 운동에서는 track reach는 감소, 각 overshoot angle 들은 증가함을 알 수 있었다.

• 한국산학기술학회논문지
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• 제21권2호
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• pp.212-220
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• 2020

본 연구는 미세 현미경 레이저 요추 디스크 절제술을 시행한 환자를 대상으로 기존의 전통적 재활플그램인 요부 안정화 운동에 SEBT 프로그램을 적용한 재활운동이 등척성 요부근력과 동적균형능력 그리고 관절가동범위에 어떠한 영향을 미치는 지를 규명하고자 실시되었다. 연구대상자는 미세 현미경 레이저 요추 디스크 절제술을 받은 후 6주간 보존적 치료를 받은 환자 14명을 대상으로, 요부안정화운동(Lumbar Stabilizing Exercise Group, LSG, n=7)과 SEBT+요부안정화운동그룹(SEBT Exercise +Lumbar Stabilizing Exercise Group, SLSG, n=7)을 8주간 실시하였다. 본 연구의 결과에서, 요부의 등척성 근력 비율(72°와 0°)은 LSG(p=.007)와 SLSG(p=.024) 모두 유의하게 감소하였으며 동적균형능력을 검사하기 위한 Y-balance test의 세 방향 도달 거리에 대한 결과는 SLSG와 LSG의 모든 방향에서 유의한 증가를 보였고 동적균형 능력은 좌측(LSG, p=.010; SLSG, p=.002)과 우측(LSG, p=.002; SLSG, p=.002) 모두 유의하게 증가하였다. 또한 관절가동범위는 LSG(p=.006)와 SLSG(p=.017) 두 집단 모두에서 유의하게 증가하였다. 이상의 결과에서 8주간의 재활운동 후, 전통적인 요부안정화 운동과 요부안정화운동에 SEBT프로그램을 추가한 재활운동 모두 등척성 요부근력과 동적균형능력 그리고 관절가동범위에 긍정적인 효과가 나타났으며 이후에 SEBT 프로그램만의 효과를 검증하는 후속연구가 필요할 것으로 사료된다.

• The Journal of Korean Physical Therapy
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• 제25권5호
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• pp.303-310
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• 2013

Purpose: The purposes of this study were to evaluate the correlation of clinical tools for assessment of balance and ability of gait, in order to discriminate the phases of sit-to-walk movement of patients with stroke using the motion analysis system, and to investigate the reliability of the phase of sit-to-walk movement according to functional ability of patients with stroke. Methods: Twenty -one patients participated (men 17, women 4) in this study. Sit-to-walk movement of all patients was recorded by the motion analysis system. Berg Balance Scale, Timed Up and Go test, Functional Reach Test, 10 meter Walk Timed Test, and Performance-Oriented Mobility Assessment were used as functional assessment tools. Results: The results of this study showed significant correlation between the phase I, II, IV and total phase duration of sit-to-walk movement and functional assessment tools. In addition, the intraclass correlation coefficient (ICC) showed high reliability in accordance with the functional ability of patients with stroke (Pearson's r 0.93 to 1.00). Conclusion: In conclusion, there is high reliability between measures of the phase of sit-to-walk movement of chronic stroke patients and the clinical assessment tool. Results of this study suggest that measurement of the phase of sit-to-walk movement can be used significantly as an intervention and a clinical tool for patients with stroke.

• 한국컴퓨터그래픽스학회논문지
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• 제8권1호
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• pp.37-45
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• 2002

본 논문은 매우 안정적이며 동시에 사실적인 직물 시뮬레이션 기법을 제안한다. 제안된 방법을 통해 안정성을 향상시킴으로써 고정된 큰 시간 간격을 사용할 수 있게 되었고, 따라서 복잡한 옷감의 변형 및 움직임을 효율적으로 시뮬레이션 할 수 있었다. 또한 제안된 방법은 직물의 가장 중요한 특성중의 하나인 주름 현상을 자연스럽게 표현한다. 안정성과 사실성에서 동시에 큰 향상을 가져올 수 있었던 것은, 수치적 안정성 외에 옷감의 좌굴 후 거동시의 불안정성을 극복함으로써 가능했다. 좌굴에 의한 불안정성은 직물의 구조적 불안정성으로부터 기인하며 단순히 암시적 시적분 방법을 사용함으로써 해결되지 않는다. 그러한 불안정성은 감쇠력을 더하여 안정성을 회복할 수 있으나 직물의 움직임을 둔화 시켜 사실적인 움직임을 얻을 수 없게 한다. 본 논문에서는 즉좌굴(immediate buckling) 가정에 기반 한 새로운 직물의 좌굴 모형을 제시한다. 즉좌굴 가정은 직물이 좌굴되는 순간 안정한 상태로 곧바로 변형되는 것을 의미하며, 이러한 가정을 통해 가상적인 감쇠력을 더하지 않고도 안정적으로 직물을 시뮬레이션 할 수 있다. 결과적으로 즉좌굴 모델은 직물의 고유한 좌굴 현상을 적절히 모델링하여 안정성을 향상시킬 뿐 아니라 외부 힘에 민감하게 반응하는 직물의 움직임을 사실적으로 생성할 수 있도록 한다.

• 한국전문물리치료학회지
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• 제9권1호
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• pp.1-15
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• 2002

The purpose of this study was to compare the balance and gait between fallers and non-fallers in elderly. A brief questionnaire was used to obtain the fall history. Twenty-seven women subjects were evaluated in this study. Eleven subjects and a mean age of 84.5 years (SD=4.6) were designated as the faller group. Sixteen subjects and a mean age of 80.3 years (SD=5.3) were designated as the non-faller group. The fall-related factors (mental status, balance, range of motion and muscle strength of lower extremity, sensation of foot, and cadence, walking velocity, stride length) were compared between faller group and non-faller group and measured. The results showed that faller group had significantly less range of motion of the hip flexion and knee extension, and strength of the knee extensor and ankle dorsiflexor and plantar flexor than non-faller group. The scores of the Functional reach test and One leg standing were significantly less in faller group than in non-faller group. Faller group showed less walking velocity and stride length compared to non-faller group. However, there was no significant difference in cadence during comfortable waking and fast walking between two groups. There were no significant differences in pressure, position sensory between two groups. These results suggest that exercise for improving the flexibility, muscle strength of the lower extremity and balance may be useful strategies to prevent fall in elderly. Further studies are needed to identify which specific factors are related to fall in the elderly population.

• Physical Therapy Rehabilitation Science
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• 제8권2호
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• pp.74-78
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• 2019

Objective: Myofascial release (MFR) is used to restore tissue extensibility of the fascia tissue and is considered to be useful in a number of clinical settings, such as low back pain (LBP). Dynamic myofascial release (DMFR) is the manual therapy, which combined the conventional MFR with the joint mobilization. The purpose of this study was to investigate the effects of the DMFR on trunk mobility, and furthermore, whether the increase of trunk mobility can carry over the improvement of dynamic standing balance in persons with chronic nonspecific LBP. Design: Randomized controlled trial. Methods: Thirty persons with chronic non-specific LBP participated in the study and were randomly assigned to the DMFR group (n=15) or the control group (n=15). DMFR was performed for two sessions (15 minutes/session) per week for four weeks for the treatment group. Both the DMFR and control groups were allowed to perform low-intensity physical activities during the treatment period. The Modified-modified $Sch{\ddot{o}}ber$ test (MMST) for trunk mobility and the Functional Reach Test (FRT) for dynamic standing balance were measured before and after the treatment period in both the DMFR group and the control group. Results: The MMST value of DMFR group increased significantly in all trunk range of motion (flexion, extension, lateral flexion, and rotation) after treatment, compared with the control group (p<0.05). Additionally, the FRT value of the DMFR group improved significantly after treatment, compared with the control group (p<0.05). Conclusions: We suggest that DMFR have a positive effect on trunk mobility and standing balance in persons with chronic LBP.