• Title/Summary/Keyword: 운동안정성

Search Result 728, Processing Time 0.024 seconds

Effect of inferomedial gliding of patella using non-eleastic taping on muscle activity of vastus medialis and vastus lateralis during sit to stand (앉은 자세에서 일어날 때 비탄력 테이핑을 이용한 무릎뼈의 아래 안쪽 활주가 안쪽넓은근과 가쪽넓은근의 근활성도에 미치는 영향)

  • Yun, Sang-Hyuk;Kang, Jong-Ho
    • Journal of Convergence for Information Technology
    • /
    • v.7 no.4
    • /
    • pp.39-43
    • /
    • 2017
  • The purpose of this study was to investigate of effect of medial & inferior gliding of patella using non-elastic taping on muscle activation of vastus medialis & vastus lateralis during sit to st&ing. As a result of measure, it was confirmed that the muscle activity of vastus medialis is higher than total muscle activity when the inferomedial gilding compared to the medial gliding. The medial & downward gliding of patella more stable than medial direction. especially it will be effective on prevent or control of Patellofemoral pain syndrome. In this regard, the development of orthosis & sportswear for inferomedial gliding to patella will be efficiency to maintain healthy the knee joint.

Wind Tunnel Test Study on the Wings of WIG Ship (WIG선의 날개에 대한 풍동실험 고찰)

  • Kim, S.K.;Suh, S.B.;Lee, D.H.;Kim, K.E.
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.34 no.1
    • /
    • pp.60-67
    • /
    • 1997
  • This paper presents the results of 3rd wind tunnel test for the wings of WIG R/C test models, 'Hanjin-1' & 'Hanjin-2'. We made 'Hanjin-1' in last May 1995 and had a success in test flight. And in order to grasp the aerodynamic characteristics of wings in ground effect, the measurements of lift and drag were carried out for the various kinds of wing. It was shown that lift and lift-drag ratio increase with decrease of the clearance, but the feature was considerably depended on the shape of wing section. In this case we select the three kind of wing. section, and then compare their characteristics especially for a stability in longitudinal motion. They are NACA6409 for 'Hanjin-1' and the two kinds of DHMTU for ekranoplans of Russia. Experimental results show that the pitching moments of DHMTU wing sections are smaller than NACA6409.

  • PDF

Conceptual Design for Mooring Stability System and Equipments of Mobile Harbor (모바일하버 선박의 계류안정화시스템 및 의장장치 개념설계)

  • Lee, Yun-Sok;Jeong, Tae-Gwon;Jung, Chang-Hyun;Kim, Se-Won
    • Journal of Navigation and Port Research
    • /
    • v.34 no.5
    • /
    • pp.311-317
    • /
    • 2010
  • Mobile Harbor(MH) is a new paradigm for maritime transport system introduced in Korea, the target of which is to carry out ship-to-ship cargo operation rapidly and effectively even under a condition of sea state 3. A MH ship is moored alongside a large container vessel anchored at the defined anchorage and also equipped with gantry cranes for handling containers. The MH study concerned includes rapid container handling system, optimum design for floating structure, hybrid berthing & cargo operation system, design for cargo handling crane, etc. This paper is to deal with a conceptual design of a stabilized mooring system and mooring equipment under a condition of ship-to-ship mooring. In this connection, we suggest a positioning control winch system in order to control heave motions of the MH ship which is to add constant brakepower and stabilized function to an auto-tension winch and mooring equipment used currently in large container ships.

Investigation of Dual-Spin Turn and Attitude Acquisition of Satellite (위성의 Dual-Spin Turn 방법 분석 및 자세획득)

  • Seo, Hyeon-Ho
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.34 no.2
    • /
    • pp.36-47
    • /
    • 2006
  • The process of dual spin turn maneuver is introduced for attitude acquisition or recovery from flat spin state of a satellite. The physical principle of momentum transfer during dual spin turn is explained clearly. The case studies of special dual spin turn, in addition to the conventional dual spin turn, that are known as an acceptable cases, are performed to investigate the principle of dual spin turn and to provide a physical insight as well as the solution of dual spin turn. This study is done based on case-study simulation, which includes two-state control scheme composed of open-loop maneuver and energy dissipation device. Furthermore, we investigate the stability for the verification of all control cases after implementing two-stage control. We also provide the simulation scenario of flat spin recovery using dual spin turn method as an example.

Improvement of Unexpected Pitch Down Tendency of an Aircraft (항공기 기수 숙임 현상 개선)

  • Kim, Chong-Sup;Kwon, Hui-Man;Koh, Gi-Ok;Han, Kwang-Ho;Lee, Seung-Deok;Hwang, Byung-Moon;Kim, Seong-Jun
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.39 no.2
    • /
    • pp.162-169
    • /
    • 2011
  • The flight control system utilize RSS(Relaxed Static Stability) criteria in both longitudinal axes to achieve performance enhancements and improve stability. The aircraft using digital flight-by-wire flight control system receives aircraft flight conditions such as pitch, roll and yaw rate, normal acceleration from RSA(Rate Sensor Assembly) and ASA(Acceleration Sensor Assembly). These sensors has permissible measurement error related to system safety of an aircraft but, unexpected flight motions are happened by sensing errors such as offset, noise and etc. The unexpected pitch down tendency occurred by ASA sensor bias in 1g level flight with pilot hands-off. This paper addresses the design and verification of flight control law to improve of pitch down or up tendency caused by ASA sensor bias. The result of analysis and flight test reveals that pitch down tendency can be improved by pitch attitude feedback system.

Clinical presentation and specific stabilizing exercise management in Lumbar segmental instability (요추분절의 불안정성에 대한 임상적 소개와 안정성 운동관리)

  • Jung Yeon-Woo;Bae Sung-Soo
    • The Journal of Korean Physical Therapy
    • /
    • v.15 no.1
    • /
    • pp.155-170
    • /
    • 2003
  • Lumbar segmental instability is considered to represent a significant sub-group within the chronic low back pain population. This condition has a unique clinical presentation that displays its symptoms and movement dysfunction within the neutral zone of the motion segment. The loosening of the motion segment secondary to injury and associated dysfunction of the local muscle system renders it biomechanically vulnerable in the neutral zone. There in evidence of muscle dysfunction related to the control of the movement system. There is a clear link between reduced proprioceptive input, altered slow motor unit recruitment and the development of chronic pain states. Dysfunction in the global and local muscle systems in presented to support the development of a system of classification of muscle function and development of dysfunction related to musculoskeletal pain. The global muscles control range of movement and alignment, and evidence of dysfunction is presented in terms of imbalance in recruitment and length between the global stability muscles and the global mobility muscles. The local stability muscles demonstrate evidence of failure of aeequate segmental control in terms of allowing excessive uncontrolled translation or specific loss of cross-sectional area at the site of pathology Motor recruitment deficits present as altered timing and patterns of recruitment. The evidence of local and global dysfunction allows the development of an integrated model of movement dysfunction. The clinical diagnosis of this chronic low back pain condition is based on the report of pain and the observation of movement dysfunction within the neutral zone and the associated finding of excessive intervertebral motion at the symptomatic level. Four different clinical patterns are described based on the directional nature of the injury and the manifestation of the patient's symptoms and motor dysfunction. A specific stabilizing exercise intervention based on a motor learning model in proposed and evidence for the efficacy of the approach provided.

  • PDF

An experimental study on the thermal entrance lengths for viscoelastic polymer solutions in turbulent tube flow (점탄성 특성을 가진 폴리머용액의 난류유동 열적입구길이에 관한 실험적 연구)

  • 유상신;황태성;엄정섭
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.12 no.5
    • /
    • pp.1189-1196
    • /
    • 1988
  • Thermal entrance lengths of turbulent tube flow for viscoelastic polymer solutions are investigated experimentally in the recirculating flow system with tubes of inside diameters 8.5mm(L/D=710) and 10.3mm(L/D=1158), respectively. In the present system, the hydrodynamic and thermal boundary layers develop simultaneously from the beginning of the test section. To provide the boundary condition of constant heat flux at the wall, the test tubes are heated directly by electricity. The polymer solution used in the current study is 1000 wppm aqueous solution of polyacrylamide(Separan AP-273). The apparent viscosity of the polymer solutions circulating in the flow system are measured by the capillary tube viscometer at regular time intervals. Thermal entrance lengths vary due to the rate of degradation. The entrance lengths of degraded polymer solutions are about 500~600 times the diameter. However, the entrance lengths of fresh polymer solutions are greater than the lengths of the test tubes used in this study suggesting that thermal entrance lengths for viscoelastic polymer solutions are greater than 1100 tube times the diameters. Friction factor is almost insensitive to the degradation, but the heat transfer $j_{H}$-factor is affected seriously by degradation. Based on the present experimental data of fresh solutions a correlation for the heat transfer $j_{H}$-factor is presented.ted.

A Study on Composition and Utilization of Digital Literacy Education elements Using Open Contents (오픈 콘텐츠를 활용한 디지털 리터러시 학습 요소 구성과 활용)

  • Hong, Myunghui;Lee, Soonyoung
    • Journal of The Korean Association of Information Education
    • /
    • v.22 no.6
    • /
    • pp.711-721
    • /
    • 2018
  • The development of artificial intelligence technology and the shift to a software-driven society are raising the need for digital literacy education on how to access, understand, use, create and share new open content in a variety of sustainable open content. At this point in time, this paper defines the digital literacy as the subliteracy concept for data, tools, and device elements. It is defined as a concept that includes cognitive and non-cognitive abilities and is stratified by computer literacy, ICT literacy, and information literacy. Open content is also defined as teaching-learning materials that can be used and shared freely by anyone, such as the Open Education Resource (OER) and the Open Access movement. Based on the two definitions, a three-step strategy for digital literacy education was developed to select open content in the digital environment, followed by a digital literacy education plan, and finally, an education frame to foster digital literacy capabilities.

Development of AUV's Waypoint Guidance Law and Verification by HILS (무인잠수정의 경로점 유도 법칙 설계 및 HILS 검증)

  • Hwang, Jong-Hyon;Yoo, Tae-Suk;Han, Yongsu;Kim, Hyun Wook
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.24 no.11
    • /
    • pp.1417-1423
    • /
    • 2020
  • This paper proposes a waypoint guidance algorithm for the Autonomous Underwater Vehicle(AUV). The proposed simplified guidance algorithm is presented, which is combined LOS guidance and cross-track guidance for path following. Cross-track error is calculated using the position of the AUV and reference path. LOS guidance and cross-track guidance are appropriately changed according to cross-track error. And the stability of the system has been improved using variable cross-track control gain by cross-track error. Also, in this paper, navigation hardware in-the loop simulation(HILS) is implemented to verify navigation algorithm of AUV that performs combined navigation using inertial navigation device and doppler velocity log(DVL). Finally, we design integrated system HILS (including navigation HILS) for performance verification of guidance algorithm of the autonomous underwater vehicle. By comparing the sea test result with HILS result, the proposed guidance algorithm and HILS configuration were confirmed be correct.

Effect of Vestibular Sensory Stimulation Exercise on Limit of Stability, Dynamic Weight Shift, and Upper and Lower Extremities Reaction Time in Adult Women (안뜰감각 자극운동이 성인여성의 안정성한계, 동적체중이동 및 팔다리 반응시간에 미치는 영향)

  • Kim, Chung-Yoo;Lee, Keon-Cheol;Lee, Yeon-Seop
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.10 no.2
    • /
    • pp.203-210
    • /
    • 2022
  • Purpose : The purpose of this study was to investigate the effect of vestibular sensory stimulation exercise on the limit of stability, dynamic weight shift, and upper and lower extremities reaction time in adult women. Methods : This study was conducted with 30 female. All subjects were randomly and equally assigned to an experimental group and a control group of 15 each. Subjects assigned to the experimental group received vestibular sensory stimulation training for 6 weeks. For the intervention, vestibular sensory stimulation exercises were conducted by referring to the Hamid exercise method and the Cawthorne-Cooksey exercise method, and the control group did not receive any intervention. All subjects were tested for limit of stability, dynamic weight shift, and upper and lower extremities reaction time before and after the intervention. Results : The results of this study showed significant differences between groups in reaction time, moving velocity, and directional control in the limit of stability test after intervention. In the dynamic weight shift test after intervention, there was a significant difference between the groups in the slow directional control of left and right. And in the upper and lower extremities reaction time test after intervention, both scores and reaction time showed significant differences between groups. Conclusion : As a result, the three vestibular sensory stimulation exercises applied in this study improved the limit of stability, dynamic weight shift, and upper and lower extremities reaction time.