• Title/Summary/Keyword: 동적 균형

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Numerical Simulation of Self-Compensating Dynamic Balancer in a Rotating Mechanism (수치해석을 통한 자기보상 동적균형기의 작동성 검토)

  • 이종길
    • Journal of the Korean Society for Precision Engineering
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    • v.12 no.1
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    • pp.142-151
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    • 1995
  • 회전체의 자동밸런싱을 위하여 고안된 자기보상 동적균형기는 홈이파인 원판에 강구와 저점성유체를 지닌 구조체이다. 유도된 운동방정식으로 부터 자기보상 동적균형기의 작동조건을 조사하기 우하여 수치해석을 통한 동 특성을 검토하였다. 수치해석의 결과에 근거하여 임계속도보다 높은 범위에서는 자기보상 동적균형기는 정상작동을 보여주었다. 임계속도에서는 회전계의 균형이 강구와 점성유체와의 감쇠계수에 의존하였으나 임계속도보다 낮은 범위에서는 어떠한 조건에 대해서도 작동하지 않음을 알 수 있었다. 자동차 및 항공기에도 응용가은한 자기보상 동적균형기의 작동조건들을 본 논문에서 예시하였다.

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The effect of unstable plate on the ankle joint displacement and dynamic balance ability of female college students wearing high-heeled shoes (불안정 판을 이용한 훈련이 높은 굽 신발을 신은 여자 대학생의 발목관절 변위와 동적균형능력에 미치는 영향)

  • Nam, Taek-Gill;Lee, Ji-Hyun
    • Journal of Convergence for Information Technology
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    • v.7 no.5
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    • pp.31-38
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    • 2017
  • The purpose of this study was to investigate the effect of training using unstable plate on displacement and dynamic balance ability of ankle joints in women college students wearing high heel shoes. Subjects were randomly divided into experimental group and control group. 3D motion analysis was performed while walking 9cm high-heeled shoes and walking 5m. Dynamic balanced ability evaluation was performed. The intervention program was administered to experimental subjects three times a week for four weeks. They performed balance training using unstable plates. There was no intervention in the control group. The results showed that the displacement of the ankle joints in the experimental group after the intervention was decreased overall and the dynamic balance ability was significantly increased. The control group showed little change. As a result, the training using unstable plate stabilizes the ankle joints and improves the dynamic balance ability of the subjects wearing high-heeled shoes.

Effects of Gastrocnemius Muscle Length on the Dynamic Balance and Antero-posterior Pressure Distribution of Foot (장딴지근 길이가 동적 균형 및 발바닥의 앞뒤 압력 분포에 미치는 영향)

  • Lee, Won-Hwee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.6
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    • pp.150-157
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    • 2019
  • The purpose of this study was investigate the effect of gastrocnemius(GCM) muscle length on the dynamic balance and antero-posterior pressure distribution of foot. Thirty subjects were recruited and each subject was classified with control experimental and control group according to GCM muscle length. The experimental group included subjects with shortness of GCM muscle length, the control group included subjects with normal length of GCM. The dynamic balance and antero-posterior pressure distribution of foot were measured by Biorescue equipment. To evaluate dynamic balance, we collected data of limit of stability in antero-posterior direction. We analyzed the data by using independent t-test. The alpha level was set 0.05. The results showed that the dynamic balance and antero-posterior pressure distribution of foot were significantly different between two groups (p<0.05). This study suggests that the shortness of GCM affects anterior limited of stability in dynamic balance and anterior pressure distribution of foot. Therefore, it is important to maintain optimal GCM muscle length for normal balance ability and prevention of musculoskeletal disease.

Elastic Demand Stochastic User Equilibrium Assignment Based on a Dynamic System (동적체계기반 확률적 사용자균형 통행배정모형)

  • Im, Yong-Taek
    • Journal of Korean Society of Transportation
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    • v.25 no.4
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    • pp.99-108
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    • 2007
  • This paper presents an elastic demand stochastic user equilibrium traffic assignment that could not be easily tackled. The elastic demand coupled with a travel performance function is known to converge to a supply-demand equilibrium, where a stochastic user equilibrium (SUE) is obtained. SUE is the state in which all equivalent path costs are equal, and thus no user can reduce his perceived travel cost. The elastic demand SUE traffic assignment can be formulated based on a dynamic system, which is a means of describing how one state develops into another state over the course of time. Traditionally it has been used for control engineering, but it is also useful for transportation problems in that it can describe time-variant traffic movements. Through the Lyapunov Function Theorem, the author proves that the model has a stable solution and confirms it with a numerical example.

The effect of trunk stabilization exercise according to face-to-face, non-face-to-face, and self-exercise on balance ability (대면, 비대면, 자가운동에 따른 체간안정화 운동이 균형능력에 미치는 영향)

  • Kyung-eun Lee;So-eun Kim;Hyun-jeong Kim;Jeongwoo Jeon;Jiheon Hong;Jaeho Yu;Jinseop Kim;Seong-Gil Kim;Yeongyo Nam;Dongyeop Lee
    • Journal of Advanced Technology Convergence
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    • v.3 no.1
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    • pp.65-72
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    • 2024
  • Study of the effect of interbody stabilization exercises on the static and dynamic balance of face-to-face, non-face-to-face, and self-group. We recruited healthy young adults The subjects were randomly divided into three groups to perform inter-body stabilization exercises, and static and dynamic balance were measured, respectively, before and after intervention. In the Face to Face Group, dynamic balance significantly increased in the anterior and posteriomedial directions before and after intervention. There was also a significant increase in static balance. In the Non face to face Group, there was a significant increase in the three directions of dynamic and static balance. The self-exercise group significantly increased in three directions of dynamic balance, but there was no significant difference in static balance. No significant differences between groups were found in any variables. The results of this study showed that interbody stabilization exercises are effective in improving static and dynamic balance. In the face-to-face group, the inter-body stabilization exercise was effective in improving dynamic balance and static balance, and in the non-face-to-face group, the inter-body stabilization exercise was effective in improving dynamic balance and static balance. In the self-contained group, it was effective in improving dynamic balance.

Modeling of Water Transportation in Dynamic Load Proton Exchange Membrane (PEM) Fuel Cell Power Generator (동적부하 PEM 연료전지 발전기에 있어서의 수분전달 모델링)

  • Agung, Bakhtiar;Choi, Kwang-Hwan;Kim, Young-Bok
    • Journal of the Korean Solar Energy Society
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    • v.31 no.2
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    • pp.1-7
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    • 2011
  • PEM 연료전지에 있어서 수분의 균형이 연료전지의 시스템 성능에 현저한 영향을 미친다. 그래서 수분 균형은 가장 중요한 요소 중의 일부가 되었으며, 이에 관한 연구가 광범위하게 이루어지고 있다. 적절한 수분 균형을 유지하기 위해서는 적당한 멤브레인 수화작용(membrane hydration)이 필요하며, 반대로 촉매층(catalyst layer)에서의 익수(water flooding)현상이 없어져야 한다. 따라서 이와 같은 동적 상태에서 PEM 연료전지 내의 수분 균형을 유지하기 위해서는, 고도의 동적 수분 조정 기술이 확보되어야 한다. 현재의 연구는 이러한 특성을 고려하여 PEM 연료전지에서 동적부하 상태에서의 수분 이동에 관한 일차원 해석 모델에 관한 것이다. 금번 모델링의 결과, 양극촉매층(CCL, cathode catalystlayer)에서의 수분 상태는 거의 포화 단계에 이르고 있음을 보여주고 있으며, 이 모델링은 연료전지가 작동되는 동안의 CCL에 나타나는 수분의 양상을 예측하는데 활용될 수 있다. 본 논문에서는 수분 이동 모델이 국제규격에 따라 다양한 수송기관이 가동될 때, 동적부하 상태에서 서로 다른 차이점을 발견하기 위한 시뮬레이션 결과에 초점이 맞추어져 있다. 이 모델링을 적용한 결과, 수분 포화도가 상태에 따라 상이하게 나타남을 알 수 있었고, 또한 정적 수분 조절 요소에 따라 최적 상태가 모든 동적 분포에 따라 달라짐을 알 수 있었다.

Effect of 8 Direction Incline and Rotation Exercise on Pain and Dynamic Balance in the Patients with Chronic Low Back Pain (8방향 경사와 회전 운동이 만성요통환자의 통증과 동적균형에 미치는 영향)

  • Goo, Bong-Oh;Park, Min-Chull;Song, Yoo-Yik;Cho, Ye-Rim
    • The Journal of the Korea Contents Association
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    • v.10 no.9
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    • pp.285-292
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    • 2010
  • The purpose of this study is to investigate the effect of 8 direction incline and rotation exercise on pain and dynamic balance in the patients with chronic low back pain(CLBP). 20 patients who were diagnosed with CLBP were included for the study. 10 patients(experimental group) were treated by modality{Hot Pack(H/P), Transcutaneous Electric Nerve Stimulation(TENS), Ultra Sound(U/S)} and then performed 8 direction incline and rotation exercise. The other 10 patients(control group) were only treated by modality. The therapeutic intervention was taken three times a week for 6 weeks. Dynamic balance was assessed by Star Excursion Balance Test(SEBT) and pain was assessed by Visual Analog Scale(VAS). VAS scores of both groups were decreased. However, the experimental group was more significantly decreased than the control group. The dynamic balance of both groups was significantly increased in anterior, posterior, medial, lateral direction. But experimental group was more significantly increased than the control group. In conclusion, 8 direction incline and rotation exercise was effective on pain and dynamic balance in CLPB.

Immediate Effects of Abdominal Hollowing Exercise and Abdominal Bracing Exercise on Dynamic Balance (복부 할로잉 운동과 복부 브레이싱 운동이 동적 균형에 미치는 즉각적 효과)

  • Jeong-In Lee;Ji-Hye Choi;Ye-Won Lee;Ji-Eun Kim;Ga-Young Lim;Jong-Yun Park;Byeong-Wook Youn;Hyeong-Kyun Yu;Min-Jae Jin;In-hyouk Hyong
    • Advanced Industrial SCIence
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    • v.2 no.2
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    • pp.16-24
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    • 2023
  • Purpose: This study was conducted to find out the immediate effect on dynamic balance through Abdominal hollowing exercise and Abdominal bracing exercise. Method: 90 healthy male and female students in their 20s were surveyed and measured using Y-balance test and Functional reach test. Result: In the dynamic balance Test between groups, there was a statistically significant difference between the group that performed Abdominal hollowing exercise and the control group. Conclusion: Although both representative spinal stabilization exercises Abdominal hollowing exercise and Abdominal bracing exercise are meaningful in increasing dynamic equilibrium, it is difficult to suggest that any method is more effective in terms of immediate effects.

Effect of Task-Oriented Exercise on the Balance in Degenerative Arthritis Patients with Total Knee Replacement (과제 지향 훈련이 슬관절 전치환술을 시행한 퇴행성 관절염 환자의 균형 능력에 미치는 효과)

  • Ji, Sang-Goo;Kim, Myung-Kwon;Lee, Dong-Geol;Cha, Hyun-Kyu
    • The Journal of the Korea Contents Association
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    • v.12 no.3
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    • pp.222-232
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    • 2012
  • This study was conducted to compare the task-oriented exercise and weight-shifting exercise program has effectiveness on the static and dynamic balance in patients with total knee replacement. The participants were allocated randomly into 2 group : task-oriented exercise group(n=12) and weight-shifting exercise group(n=12). To evaluate the effects of exercise, subjects were evaluated by using Gaitveiw System and functional reaching test for static balance and Balance System for dynamic balance test. The data was analyzed using a paired t-test and independent t-test to determine the statistical significance. Static balance test and dynamic balance test in task-oriented exercise had statistical significance than weight-shifting exercise program(p<0.05). So this results were suggested that the task-oriented exercise was effective on static and dynamic balance in patients with total knee replacement.