• 제목/요약/키워드: Limits of Stability

검색결과 351건 처리시간 0.028초

교합안정장치가 신체 균형에 미치는 영향 (Effect on Body Balance due to Occlusal Biteplane Splint)

  • 김정욱;박민철;최성민;이상열;원현진
    • 한국콘텐츠학회논문지
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    • 제13권4호
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    • pp.273-280
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    • 2013
  • 본 연구의 목적은 교합안정장치의 착용이 신체의 균형에 미치는 영향을 알아보기 위함이다. 연구 대상자는 교합과 저작계에 이상이 없고, 보행에 지장이 없으며, 악관절의 병력을 가지고 있지 않은 10명을 대상으로 하였다. 신체 균형은 Fukuda stepping test, Stability of limit test를 이용하여 측정하였으며, 교합안정장치 착용 전과 착용 후의 유의성을 검정하기 위하여 Wilcoxon signed test를 실시하였다. 통계학적인 유의성을 검정하기 위한 유의수준 ${\alpha}$는 .05로 하였다. 연구 결과 교합안정장치 착용 전과 착용 후에 Fukuda stepping test의 이동거리와 Stability of limit test에서 유의한 차이가 있었다(p<.05). 본 연구의 결과를 통해 교합안정장치의 착용은 신체 균형에 긍정적인 효과가 있음을 알 수 있었다.

보염기에 의해 안정되는 난류확산화염의 연소특성에 관한 연구 (A Study on the Combustion Characteristics of Turbulent Diffusion Flame Stabilized by Bluff Body)

  • 안진근;송규근
    • 한국연소학회지
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    • 제3권1호
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    • pp.71-78
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    • 1998
  • The flame stabilization and the combustion characteristics of diffusion flame formed in the wake of a cylindrical bluff body with fuel injection are studied. With the turbulence generator, the flame stability limits and ion currents were measured and analyzed. The results from this experimental study are summarized as follows. The region with highest average value of ion currents in the middle of flame is moved to the upstream side by the turbulent components of main stream. The flame mass with partially active reaction is moved fast for uniform flow and turbulence generator G3, but the flame mass with relatively slow reaction is moved slowly for turbulence generator G1. If the turbulence generator with strong turbulent component is installed, the turbulent time scale is increased with movement from main stream side to recirculation zone as well as the flame stability limits is deteriorated. Though the special dominant frequency is not appeared in the eddy which exists in flame, high frequency characteristics are appeared in uniform flow and turbulence generator G3, and low frequency characteristics are appeared in uniform flow, turbulence generator G3 and G1.

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고유수용성 조절과 시각적 피드백이 만성 편마비 환자의 안정성 한계에 미치는 영향 (The Effects of the Proprioceptive Control and Visual Feedback for the Limits of Stability in Patients with Chronic Hemiplegia)

  • 황병용
    • The Journal of Korean Physical Therapy
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    • 제19권6호
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    • pp.37-41
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    • 2007
  • Purpose: Hemiplegic patients usually present with difficulties in maintaining their balance. Balance retraining is a major component of a rehabilitation program for patients with neurological impairments. This study compared the effects of prorpioceptive exercise and visual feedback program on the limits of stability (LOS) in chronic hemiplegia patients. Methods: Thirty subjects (mean age $57.0{\pm}9.8$) were recruited. The subjects were divided into a proprioceptive group and a visual group. The subjects for the proprioceptive group participated in the proprioceptive exercise program for 4 weeks, and the visual group were treated with visual feedback training using a Balance Master. Results: At the 4 week follow-up test, the LOS in the proprioceptive group improved significantly in all directions (p<0.05). However, improvement was only observed in the forward direction in the visual feedback group. Therefore, the proprioceptive control approach improves the LOS in chronic hemiplegia patients. Conclusion: These results suggest that compared with physical therapy alone using a proprioceptive control approach to hemiplegia, there was no additional benefit of visual feedback training, such as Balance Master, when administrated in combination with other physical therapy interventions.

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The Effects of Ankle Strengthening Training and Whole Body Vibration on the Balance of Older Adults Who Have Experienced a Fall

  • Choi, Jung Hyun;An, Ho Jung
    • 국제물리치료학회지
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    • 제6권2호
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    • pp.884-890
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    • 2015
  • This study observed the effects of ankle strengthening exercise and whole body vibration on the balance ability of older adults, thereby intending to provide basic materials for intervention methods aimed at improving older adults' balance ability. The subjects were 20 older adults who had experienced a fall. They were equally divided into two groups. Ankle strengthening training was applied to one group and ankle strengthening training and whole body vibration were applied to the other group, a timed up and go (TUG) test and Tinetti performance oriented mobility assessment (POMA) were performed, and changes in the subjects' limits of stability were observed. The TUG and POMA results significantly differed between before and after the experiment in the angle strengthening training (AST) group and the angle strengthening training with whole body vibration (ASTWV) group. In addition, the interaction between timing and each group was statistically significant. The limits of stability significantly changed after the intervention in both groups. Differences in the posterior and right limits of stability were significant between the AST group and ASTWV group. Therefore, ankle strengthening exercise and whole body vibration improve older adults' balance maintenance and reduce falls or the risk factors for falls in older adults.

액체 로켓엔진에서 선형 연소 안정한계에 미치는 유한화학반응 및 막냉각 효과 (Effects of Finite-Rate Chemistry and Film Cooling on Linear Combustion-Stability Limit in Liquid Rocket Engine)

  • 손채훈;박이선;문윤완;김홍집;오화영;허환일
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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    • pp.189-193
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    • 2005
  • 로켓엔진에서 선형 연소 안정한계에 미치는 유한화학반응의 열적 효과와 막냉각 효과를 조사하였다. 안정한계를 평가하기위해 3차원 연소실에서 유한화학반응을 채택한 반응 유동장 계산으로부터 구한 유동변수들을 사용하였다. 주요 유동변수들의 값은 유한화학반응 모델의 채택으로 인해 상당히 달라졌으며 결과적으로 안정한계도 수정되었다. 유한화학반응은 열적 관점에서 안정성 향상에 기여함을 알았다. 또한, 막냉각을 한 경우, 안정성 경향이 향상됨을 알 수 있었다.

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에너지함수법을 이용한 가용송전용량(ATC) 계산에 관한 연구 (A study on the ATC(Available Transfer Capabilily) calculation using an Energy Function Method)

  • 김재현;정성원;김양일
    • 조명전기설비학회논문지
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    • 제22권2호
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    • pp.94-100
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    • 2008
  • 가용송전용량(ATC)은 계통내의 한 지역에서 다른 지역까지 실제 전력을 증가시키는 것이다. 지금까지 ATC 계산은 대부분 정상상태에서 실행가능성을 주로 고려하여 계산되어 왔다. 하지만 ATC 평가시 과도안정도로 제약된 ATC 계산은 매우 중요한 부분이다. ATC 평가시에는 제약조건으로 열적용량, 전압 및 과도안정도로 제약된 상정사고(n-1)시 안전도 평가가 요구된다. 본 논문은 자코비안 행렬의 고유치를 이용하여 상정사고 우선순위를 선정하였고, 에너지 함수법을 이용하여 선로의 열적용량, 전압안정도 및 과도안정도를 고려한 ATC를 계산하였다.

액체 로켓엔진에서 선형 연소 안정한계에 미치는 유한화학반응 및 막냉각 효과 (Effects of Finite-Rate Chemistry and Film Cooling on Linear Combustion-Stability Limit in Liquid Rocket Engine)

  • 손채훈;김홍집;허환일;박이선;문윤완
    • 한국항공우주학회지
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    • 제34권2호
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    • pp.75-81
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    • 2006
  • 로켓엔진에서 선형 연소 안정한계에 미치는 유한화학반응의 열적 효과와 막냉각 효과를 조사하였다. 안정한계를 평가하기위해 3차원 연소실에서 유한화학반응을 채택한 반응 유동장 계산으로부터 구한 유동변수들을 사용하였다. 주요 유동변수들의 값은 유한화학반응 모델의 채택으로 인해 상당히 달라졌으며 결과적으로 안정한계도 수정되었다. 유한화학반응은 열적 관점에서 안정성 향상에 기여함을 알았다. 또한 막냉각을 한 경우, 안정성 경향이 향상됨을 알 수 있었다.

SOLUTION AND STABILITY OF AN n-VARIABLE ADDITIVE FUNCTIONAL EQUATION

  • Govindan, Vediyappan;Lee, Jung Rye;Pinelas, Sandra;Noorsaba, Abdul Rahim;Balasubramanian, Ganapathy
    • Korean Journal of Mathematics
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    • 제28권3호
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    • pp.613-621
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    • 2020
  • In this paper, we investigate the general solution and the Hyers-Ulam stability of n-variable additive functional equation of the form $${\Im}\(\sum\limits_{i=1}^{n}(-1)^{i+1}x_i\)=\sum\limits_{i=1}^{n}(-1)^{i+1}{\Im}(x_i)$$, where n is a positive integer with n ≥ 2, in Banach spaces by using the direct method.

인지적 게임을 이용한 능동적 두경부 움직임 훈련이 뇌졸중 환자의 균형에 미치는 영향 (Effects of Active Craniocervical Movement Training Using a Cognitive Game on Stroke Patients' Balance)

  • 김미선;최우성;최종덕
    • 한국전문물리치료학회지
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    • 제28권1호
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    • pp.47-52
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    • 2021
  • Background: Compared with normal people, stroke patients have decreased voluntary craniocervical motion, which affects their balance. Objects: This study was conducted in order to examine the effects of active craniocervical movement training using a cognitive game on stroke patient's cervical movement control ability, balance, and functional mobility. Methods: The subject of this study were 29chronic stroke patients who were randomly allocated to either an experimental, cognitive game group (n = 15), or control group (n = 14), to which only neuro-developmental treatment (NDT) was applied. The intervention was conducted 5 times per week, 30 minutes per each time, for a total of 4 weeks. Active angle reproduction test, static stability test, limits of stability test, and Time up and Go (TUG) test, respectively, were carried out in order to evaluate cervical movement control ability, static balance, dynamic balance, and functional mobility. Paired t-test was used in order to compare differences between prior to after the intervention, along with an independent-test in order to compare prior to and after-intervention differences between the two groups. Results: After the craniocervical training with a body-driven cognitive game, the experimental group showed significant differences in flexion, extension, and lateral flexion on the affected side, and rotation on the affected side in the active angle reproduction test. The experimental group indicated significant differences in sway length both with eyes-open and with eyesclosed in the static stability test and in limits of stability test and TUG test. The control group to which NDT was applied had significant differences in flexion in the active angle reproduction test and in limits of stability test and TUG test. Conclusion: The above results mean that craniocervical training using a body-driven cognitive game positively influences stroke patient's cervical movement control ability and as a result their balance and functional mobility.

부하역률 제약조건을 고려한 최적 급전 알고리즘 (The Optimal Power Flow Algorithm Considering Load Power Factor Limits)

  • 김광욱;조종만;김진오
    • 대한전기학회논문지:전력기술부문A
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    • 제53권9호
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    • pp.494-499
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    • 2004
  • This paper presents to compute the power economic dispatch, an optimal power flow (OPF) computation algorithm, considering the load power factor limits constraint in developed. Efficient reactive power planning enhances economic operation as well as system security. Accordingly, an adequate level of power factor limits for the load busesshould be evaluated for economic operation. In this paper, the ranges of acceptable load power factors are portrayed as bandwidths of load power factor expressed as a function of load level. The load power factor limits are included and described into the OPF's objective function. The method Proposed is applied to IEEE 26 bus system.