• 제목/요약/키워드: Random Balance Design

검색결과 28건 처리시간 0.028초

An energy-based design for seismic resistant structures with viscoelastic dampers

  • Paolacci, F.
    • Earthquakes and Structures
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    • 제4권2호
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    • pp.219-239
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    • 2013
  • The present paper aims at studying the seismic response of structures equipped with viscoelastic dampers (VED). The performance of such a passive control system is here analyzed using the energy balance concept, which leads to an optimal design process. The methodology is based on an energy index (EDI) whose maximization permits determination of the optimal mechanical characteristics of VED. On the basis of a single degree of freedom model, it is shown that the maximum value of EDI corresponds to a simultaneous optimization of the significant kinematic and static response quantities, independently of the input. By using the proposed procedure, the optimal design of new and existing structures equipped with VED, inserted in traditional bracing systems, are here analyzed and discussed.

일가족 양립 정도에 대한 인식: 집단간 비교 분석을 중심으로 (An Analysis of Group Differences on Perceived Work-Family Balance)

  • 장수정;송다영;김은지
    • 한국사회복지학
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    • 제61권2호
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    • pp.349-370
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    • 2009
  • 본 연구는 일가족 양립 인식정도에 대한 집단간 차이를 탐색하는데 목적이 있다. 이를 위하여 본 연구는 서울 및 수도권 지역에서 배우자와 함께 살고 있으며 일을 하고 있는 25세 이상 성인 1,490명을 대상으로 일가족양립 정도 및 수준에 대한 인식을 연구하기 위해 확률표본에 기반한 설문조사를 실시하였다. 주요 연구결과를 살펴보면, 성별로는 남성보다 여성 특히, 여성홀벌이들이 가족-일 양립 문제가 상당히 심각하였다. 연령대별로는 20대, 자녀수별로는 자녀가 한명인 경우 가족-일 양립에 가장 어려움을 경험하고 있었다. 고용형태별로는 정규직이, 기업규모별로는 300-900인 규모 사업장에서 일을 하고 있는 근로자들이 일-가족 양립의 문제가 심각한 것으로 나타났다. 산업별로는 교육 및 보건 등과 같은 서비스산업에서 일하는 사람들이 가족-일 양립의 문제가 심각한 것으로 나타났다.

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The effect of gait training with an elastic ankle-foot orthosis on balance and walking ability of persons with chronic stroke: a randomized controlled trial

  • Chi, Ming Hao;Yim, Jong Eun;Yi, Dong hyun
    • Physical Therapy Rehabilitation Science
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    • 제9권4호
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    • pp.222-229
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    • 2020
  • Objective: The purpose of this study was to investigate the effect of treadmill exercise on the posture and walking speed of chronic stroke survivors with an ankle-foot orthosis. Design: Randomized controlled trial. Methods: Twenty-four chronic persons with chronic stroke admitted to Bobath Memorial Hospital in Seongnam city were divided into two groups by random blind method. Treadmill exercise with an elastic ankle-foot orthosis was performed in the experimental group and treadmill exercise was performed in the control group. The experiment was carried out for 6 weeks, and the experiment was carried out three times a week for 20 minutes per session. To measure the effect, static balance was measured using the MTD system before and after training, and the Berg Balance Scale (BBS) was used to measure functional balance. Results: There was a statistically significant difference between the 2 groups in the BBS measurement results for confirming the functional balance (p<0.05). Also, there was a significant difference between the 2 groups in single limb support time, step time and step length (p<0.05). Conclusions: In this study, it was found that treadmill exercise with an elastic ankle-foot orthosis in persons with chronic stroke was effective in maintaining functional balance, walking ability, step length, and step time. Therefore, it is necessary to use a flexible ankle-foot orthosis with proper treadmill exercise as a method of improving balance and walking speed of chronic stroke survivors.

Effects of 3-dimensional balance trainer in combination with a video-game system on balance and gait ability in subacute stroke patients

  • Ha, Hyun Geun;Ko, Young Jun;Lee, Hwang Jae;Lee, Wan Hee
    • Physical Therapy Rehabilitation Science
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    • 제3권1호
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    • pp.7-12
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    • 2014
  • Objective: The purpose of this study was to investigate the effects of a three dimensional balance trainer in combination with a video-game system and visual feedback on balance recovery and gait function in subacute stroke patients. Design: Randomized controlled trial. Methods: Twenty-three subacute stroke patients were assigned to either an experimental (n=12) or a control group (n=11) using a random permuted block design and sealed envelopes. The experimental group received additional 3-dimensional balance training combined with visual feedback and a game program for 30 min/day, 5 days/week for 4 weeks. Both groups received 30-min of conservative physical therapy sessions based on neurodevelopmental therapy. Before and after the 20 sessions, walking abilities were evaluated by the the GaitRite system and balances were evaluated using the Berg Balance Scale (BBS). The Trunk Impairment Scale (TIS) was used to assess trunk muscle performances. Results: After the 4-week intervention, BBS and TIS scores were significantly increased in both groups (p<0.05), and increases in these scores were significantly greater in the experimental group (p<0.05). After the 4-week intervention, gait speed and cadence were significantly increased in both groups (p<0.05), and as was observed for BBS and TIS scores, changes of gait speed and cadence were significantly greater in the experimental group (p<0.05). Conclusions: The study shows that the 3-dimensional balance trainer combined with visual biofeedback and a video-game system provides a therapeutic means for improving balance and gait ability in subacute stroke patients.

선택적 지지면에 따른 스쿼트 운동이 정상 성인의 균형조절능력에 미치는 영향 (The Effect of the Squat Exercise by Different Baseform on Balance Ability Enhancement in Normal Adult)

  • 김민수;서인열;정고운;이건철;정한신
    • 대한통합의학회지
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    • 제1권3호
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    • pp.63-78
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    • 2013
  • PURPOSE : This study aims to investigate the positive correlation in pre-post test design between squat exercise on different baseform and the static/dynamic balance ability enhancement in adults. METHOD : This clinical study was designed into three different random-sampling adult groups (flat, balanced, vibration exercise device) and performed squat exercise. The static/dynamic balance ability was measured prior to the intervention and vice-versa. Balance was examined using the balance master 7.0 version systems. RESULT : 1) After the intervention, the controlled mat group in mCTSIB has showned the minimal mean value and the variation regards as acceptable by statistic value. 2) After the intervention, The mean value of LOS shows the minimal average variation in Randomised Trials, but the other two trials shows the maximal fluctuation. The difference variation regards as acceptable statistic value. 3)After the intervention, the mean value of mat group measrued as the maximal results, the difference variation regards as acceptable statistic value. 4)The striking correlation difference at mCTSIB has found in the vibration device exercise group, but LOS and Rhythmic W-S showed the correaltion in Mat group. CONCLUSION : The study found the positive correlation that enhanced balance ability on the different dynamic baseform squat exercise than static baseform environment. The significant difference found the balance pad squat effects on developing balance ability and the correlationship regards as statistically significant value.

Immediate Effects of Ankle Eversion Taping on Balance and Gait Function in Patients with Chronic Stroke: A Randomized Controlled Trial

  • Hye-In Bae;Myeong-Ho Lee;Myoung-Kwon Kim
    • 대한물리의학회지
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    • 제18권2호
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    • pp.1-11
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    • 2023
  • PURPOSE: This study examined the immediate effects of applying ankle eversion taping using kinesiology tape in chronic stroke patients-design: a randomized cross-over trial. METHODS: Seventeen stroke patients underwent three interventions in random order. The subjects were initially assigned randomly to an ankle eversion taping, placebo taping, or no taping for each intervention. Ankle eversion taping was used for mechanical correction and was involved in ankle dorsiflexion and eversion. The tape was stretched by 30-40%. Placebo tapping was applied in the same form as eversion tapping but was not stretched. The balance ability was assessed using the Y-balance test. The gait ability was assessed by maximum foot pressure and time of stance phase, and gait speed was assessed using a 10 m walk test (10MWT). All measurements were performed immediately after the intervention. RESULTS: The results showed that the dynamic balance and stance phase time in chronic stroke patients was improved after ankle eversion taping. The ankle eversion taping conditions increased significantly (p < .05) compared to the placebo and no taping conditions. CONCLUSION: The application of ankle eversion taping that uses kinesiology tape instantly increased the gait ability of chronic stroke patients. On the other hand, more research will be needed to identify the long-term effects of ankle eversion taping.

단자유도 건물의 지진응답제어를 위한 마찰감쇠기 설계 (Design of Friction Dampers for Seismic Response Control of a SDOF Building)

  • 민경원;성지영
    • 한국소음진동공학회논문집
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    • 제20권1호
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    • pp.22-28
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    • 2010
  • Approximate analysis for a building installed with a friction damper is performed to get insight of its dynamic behavior. Energy balance equation is used to have a closed analytical form solution of dynamic magnification factor(DMF). It is found out that DMF is dependent on friction force ratio and resonance frequency. Approximation of DMF and equivalent damping ratio of a friction damper is proposed with such assumption that the building with a friction damper shows harmonic steady-state response and narrow banded response behavior near resonance frequency. Linear transfer function from input external force to output building displacement is suggested from the simplified DMF equation. Root mean square of a building displacement is derived under earthquake-like random excitation. Finally, design procedure of a friction damper is proposed by finding friction force corresponding to target control ratio. Numerical analysis is carried out to verify the proposed design procedure.

Effects of Non-Contact Complex Exercise Program on the Older over 65 Years of Age on Muscle Strength, Falling Efficacy and Balance Ability

  • Sam Ho Park;Youn Jung Oh;Myung Mo Lee
    • Physical Therapy Rehabilitation Science
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    • 제12권2호
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    • pp.167-176
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    • 2023
  • Objective: The purpose of this study was to investigate the effects of anon-contact complex exercise program on muscle strength, fall efficacy, quality of life, and balance ability in older over 65 years of age. Design: A randomized controlled trial Methods: A total of 37 people in older over 65 years of age participated in the study. Random program was conducted and assigned to the experimental group (n=19) and the control group (n=18). Both groups performed the older people welfare center program. In addition, in the experimental group, a non-contact complex exercise program for muscle and balance exercise was performed. All interventions were performed 2 times a week, for a total of 6 weeks. chair stand test (CST), fall efficacy scale (FES), Euro quality of life 5 dimension (EQ-5D), Berg balance scale (BBS), timed up and go test (TUG), Fullerton advanced balance scale (FAB) were measured before and after the intervention to compare their effectiveness. Results: Both groups showed significant differences in CST, FES, EQ-5D, BBS, and TUG before and after intervention (p<0.05). FAB showed significant differences before and after intervention in all items except for FAB 8 and 9 items in the experimental group. In addition, the experimental group showed significant differences in CST, FES, BBS, TUG, FAB (except 1, 7, 8, 9) compared to the control group (p<0.05). Conclusions: The non-contact complex exercise program is an effective intervention method that has clinical significance in improving muscle strength, fall efficacy and static and dynamic balance abilities for the older over 65 years of age.

마찰감쇠기가 설치된 건물 응답의 근사해 : 재 고찰 및 새로운 결과 (Approximate solution for a building installed with a friction damper : revisited and new result)

  • 민경원;성지영;이성경
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2009년도 추계학술대회 논문집
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    • pp.850-854
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    • 2009
  • Approximate analysis for a building installed with a friction damper is revisited to get insight of its dynamic behavior. Energy balance equation is used to have a closed analytical form solution of dynamic magnification factor (DMF) for the building with combined viscous and friction damping. It is found out that DMF is dependent on friction force ratio and resonance frequency. Linear transfer function from input external force to output building displacement is obtained by simplifying DMF equation. Root mean square of building displacement is derived under earthquake-like random excitation. Finally, design of friction damper is proposed by processing target control ratio, damping ratio factor, and friction force in sequence.

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Learning Less Random to Learn Better in Deep Reinforcement Learning with Noisy Parameters

  • Kim, Chayoung
    • 한국정보기술학회 영문논문지
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    • 제9권1호
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    • pp.127-134
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    • 2019
  • In terms of deep Reinforcement Learning (RL), exploration can be worked stochastically in the action of a state space. On the other hands, exploitation can be done the proportion of well generalization behaviors. The balance of exploration and exploitation is extremely important for better results. The randomly selected action with ε-greedy for exploration has been regarded as a de facto method. There is an alternative method to add noise parameters into a neural network for richer exploration. However, it is not easy to predict or detect over-fitting with the stochastically exploration in the perturbed neural network. Moreover, the well-trained agents in RL do not necessarily prevent or detect over-fitting in the neural network. Therefore, we suggest a novel design of a deep RL by the balance of the exploration with drop-out to reduce over-fitting in the perturbed neural networks.