• Title/Summary/Keyword: 안정한계

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Immediate Effects of Abdominal Pressure Belt on Limited of Stability and Gait Parameter in Patients after Chronic Stroke: one-group pretest-posttest design (복부압박벨트가 만성 뇌졸중 환자의 균형 및 보행에 즉각적으로 미치는 융복합적 영향)

  • Park, Shin-Jun;Cho, Kyun-Hee
    • Journal of the Korea Convergence Society
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    • v.11 no.4
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    • pp.63-69
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    • 2020
  • This study was conducted to investigate the immediate effects of abdominal pressure blet on limited of stability and gait parameter in patients after stroke. Thirty stroke patients were recruited to measured pre and post wearing the abdominal pressure belt. The assessment measured limited of stability and spatiotemporal gait parameter. This study result were significantly increase in paretic side area, non-paretic side area, forward side area, backward side area (p<.05) and cadence, gait velocity, stride length (p<.05). This study found that abdominal pressure belt had an immediate effect on improving balance and gait function in stroke patients. Future studies require studies of efficient abdominal pressure levels and intervention periods to improve the balance and walking function of stroke patient.

Comparison of Safety factor for an Anchored Slope in Accordance with the Effects of Load Transfer (앵커 하중전이에 따른 사면의 안전율 비교 연구)

  • Kim, Sung-Kyu;Kim, Wak-Kyung;Park, Jong-Sik;Joo, Yong-Sun;Kim, Tae-Hoon
    • Journal of the Korean Geotechnical Society
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    • v.24 no.11
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    • pp.55-60
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    • 2008
  • This paper presents how the load transfer mechanism of the ground anchor affects on the stability analysis of anchored slope. The finite element analysis and the conventional limit equilibrium analysis on the anchored slope were performed and compared. The limit equilibrium analysis of the anchored slope is widely used in design practice due to the easiness of the analysis. However, the load transfer mechanism is not considered properly for the analysis. When the failure surface passes through the bonded length of an anchor, the anchor load is disregarded and the factor of safety for the anchored slope is smaller than it should be. In this study, the load transfer distribution was incorporated into the limit equilibrium stability analysis of the anchored slope and the results were compared with those of finite element analysis.

연구실탐방 - 산업설비안전성평가 연구센터

  • Korean Federation of Science and Technology Societies
    • The Science & Technology
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    • v.30 no.8 s.339
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    • pp.90-91
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    • 1997
  • 수명이 한계에 이른 원자력설비ㆍ교각ㆍ대형건물 등의 안정성평가 핵심기술개발을 위해 성균관대 안에 설립한 산업설비안정성평가연구센터. 성대교수 11명과 타 대학교수 11명 등 22명의 연구진으로 구성된 이 센터는 신뢰성있는 안정성평가를 위한 통합관리시스템의 자체 개발을 위한 연구를 계속하고 있다.

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Stability Evaluation of failed Slope in Gohan, Korea using Numerical Analysis (강원도 정선군 고한 지역 붕괴사면의 수치해석을 이용한 사면안정성 평가)

  • Jang, Hyun-Sic;Lee, Ju-Young;Seo, Yong-Seok;Jang, Bo-An
    • The Journal of Engineering Geology
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    • v.24 no.4
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    • pp.511-523
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    • 2014
  • Limit equilibrium analysis and finite difference analysis were used to evaluate slope stability in the in Gohan, Korea, which is affected by large-scale tensile cracks and uplift. There is a thick colluvial layer in the study area and predicting ground behavior is problematic because the presence of clay makes it difficult to determine the strength parameters of the soil. Consequently, a numerical model able to reflect the collapse properties of the site was required that applied the modified boundary layer model and calculated the strength parameters using back analysis. The numerical simulation results that consider the strength parameter one does with the present situation the establishment of the pile is completed, and the simulation is able to asses ground stability in complex terrain in a reliable manner. Also the somewhat it judges with the fact that it will be able to provide the fundamental data which secures the stability of the segment where it is unstable.

A Study of Flame Visualization of the APU Gas Turbine Engine Sector Combustor (APU용 가스터빈 엔진 분할연소기의 화염가시화 연구)

  • Kim, Bo-Ra-Mi;Choi, Chea-Hong;Choi, Seong-Man
    • Journal of the Korean Society of Propulsion Engineers
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    • v.15 no.4
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    • pp.11-17
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    • 2011
  • In order to see flame behavior in the annular reverse gas turbine combustor, sector combustion test was performed. Ignition test by using torch ignition system was carried out at various combustor inlet velocity and air fuel ratio. Also, flame blow out limit was measured by changing fuel flow rate with constant air mass flow rate. In test results, stable ignition is possible at air excess ratio of 6 and this limit is gradually increased with combustor inlet velocity. The minimum blow out limit is about 4 at 40 m/s of combustor inlet velocity. This blow out limit is also increased up to about 10 with increasing combustor inlet velocity. Test result shows that lean blow out limits are increased with air velocity. The highest blow out limit was found at the combustor inlet velocity of 65 m/s.

A Study of Flame Visualization of the APU Gas Turbine Engine Sector Combustor (APU용 가스터빈 엔진 분할연소기의 화염가시화 연구)

  • Kim, Bo-Ra-Mi;Choi, Chea-Hong;Choi, Seong-Man
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.11a
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    • pp.153-159
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    • 2010
  • In order to see the flame behavior in the annular reverse gas turbine combustor, sector combustion test was performed. Ignition test by using torch ignition system was carried out at the various combustor inlet velocity and air fuel ratio. Also, flame blow out limit was measured by changing fuel flow rate with constant air mass flow rate. In the test results, stable ignition is possible at air excess ratio of 6 and this limit is gradually increased with combustor inlet velocity. The minimum blow out limit is about 4 at 40 m/s of combustor inlet velocity. This blow out limit is also increased up to about 10 with increasing combustor inlet velocity. Test result shows that lean blow out limits are increased with air velocity. The highest blow out limit was found at the combustor inlet velocity of 65m/s.

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An Analytical Study on the Relationship between Factor of Safety and Horizontal Displacement of Soil Nailed Walls (쏘일네일 보강벽체의 수평변위와 안전율과의 관계 분석연구)

  • Kim, Hongtaek;Lee, In
    • Journal of the Korean GEO-environmental Society
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    • v.12 no.2
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    • pp.45-53
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    • 2011
  • Soil nailing method was often designed by the slope stability analysis based on limit equilibrium. However, in the case of shorten length of nails, although the calculated factor of safety is within the design factor of safety, the horizontal displacement of soil nailed walls occurred above the allowable limit. In this study, relationship between the load and factor of safety, and relationship between the load and displacement ratio based on the test results were analysed. From the analysed results, the relationship between factor of safety and displacement ratio was estimated. For the mobilized horizontal displacement of the walls within the serviceability limit corresponding to the displacement of less than 0.3% displacement ratio, the calculated factor of safety by limit equilibrium analysis had to satisfy above 1.35. Also, although the minimum factor of safety is estimated above 1.35, the maximum horizontal displacement is often mobilized above 0.3% of excavation height. Therefore, it is necessary to perform the numerical analysis of soil nailed walls in the case of low shear strength or high excavation.

An Experimental Study on Hydraulic Stability of Non-toxic Revetment Block (무독성 호안블록의 수리학적 안정성에 관한 실험적 연구)

  • Kim, Sang Woo;Koo, Young Min;Kim, Young Do;Park, Jae Hyeon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.3
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    • pp.987-995
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    • 2013
  • The purpose of this study is to examine the hydraulic stability of non-toxic revetment technique for eco-friendly design of the domestic river restoration. Recently, instead of the flood control function-oriented river management policy for the engineering efficiency, the improvement of the environmental performance for the ecological river restoration project is implemented. However, the inappropriate hydraulic design criteria of the new revetment technique happen to the economic losses at flood season frequently. The hydraulic stability of the riprap and the block include the banks of rivers, riverbed protection, scour protection and so on. In this study, the high speed experimental channel was developed, which has the maximum velocity of 3.5 m/s, to perform the hydraulic experiments of the block method with non-toxic glue with various conditions to find the critical velocity of the revetment block for the hydraulic stability.

Agro-climate Characteristics and Stability in Crop Production of Daegwallyeong Area in Korea (기상자료 분석을 통한 대관령 지역의 작물 최저 한계온도일 추정)

  • Ryu, Jong-Soo;Lee, Jeong-Tae;Lee, Gye-Jun;Oh, Dong-Shig
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.1153-1156
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    • 2012
  • Daegwallyeong area to be formed along the mountainous terrain more above 800 m of sea level is known as the cold zone to occur frequently wind, rain and fog. This study to evaluate the stability of crop production and agricultural production potential in the Daegwallyeong was calculated for the low temperature frequency of occurrence and potential evapotranspiration changes with announce the release of Korea Meteorological Administration (KMA) from 1972 to 2009 up to 38 years. Evapotranspiration calculated FAO and other international standard method authorized under the PENMAN-MONTEITH Method was used, and the low temperature onset and frequency of the Gumbel probability density function was used. As a result, the variation of day evaporation for 38 years were showed to respectively width of variation from maximum $9mm\;day^{-1}$ to minimum $0.5mm\;day^{-1}$. The frequency of reappearance to first emergence day that lasts more than 5 days with temperature $5^{\circ}C$ over is 3 April a 50-year frequency, 10 April a 25-year frequency, 20 April a 10-year frequency, 28 April a 5-year frequency, 8 May a 2-year frequency. Psychrotrophic crop to growth temperature more than $5^{\circ}C$ can be secured to stable production with planting after May 8, prior to planting for normal growth can be seen that the risk of growth.

On the Stability and Performance Limits of the Force Reflecting Haptic Manipulator (가상반발력을 생성하는 햅틱장비의 안정성과 성능한계에 관한 연구)

  • ;Greg R. Luecke
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.12
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    • pp.180-187
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    • 1998
  • The stability and theoretical performance limits of the feedback controlled force reflecting haptic manipulator have been discussed. All the virtual environment which interact physically with the haptic system have its own stable performance limit. Three different realization of the interfaces have been compared using the driving point admittance. The haptic system which is separated from the human hand or finger is superior to its stable interaction provided that there is a means to apply a direct damping between the haptic manipulator and the human finger Electro-magnetic force is used for its digital implementation of the simple separated type haptic device. The stable limits of a virtual wall is calculated and experimental results show that there is performance limits in this implementation.

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