• The Journal of Korean Physical Therapy
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• 제30권1호
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• pp.14-22
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• 2018

Purpose: This study examined the effects of the lower limb alignment on the pelvis, hip, and knee kinematics in people with genu varum during stair walking. Methods: Forty subjects were enrolled in this study. People who had intercondylar distance ${\geq}4cm$ were classified in the genu varum group, and people who had intercondylar distance <4cm and intermalleolar distance <4cm were placed in the control group. 3D motion analysis was used to collect the pelvis, hip, and knee kinematic data while subjects were walking stairs with three steps. Results: During stair ascent, the genu varum group had decreased pelvic lateral tilt and hip adduction at the early stance phase and decreased pelvic lateral tilt at the swing phase compared to the control group. At the same time, they had decreased minimal hip adduction ROM at the early stance and decreased maximum pelvic lateral tilt ROM and minimum hip rotation ROM at the swing phase. During stair descent, the genu varum group had decreased pelvic lateral tilt at the early stance and decreased pelvic lateral tilt and pelvic rotation at the swing phase. In addition, they had decreased pelvic frontal ROM during single limb support and increased knee sagittal ROM during the whole gait cycle. Conclusion: This study suggests that a genu varum deformity could affect the pelvis, hip and knee kinematics. In addition, the biomechanical risk factors that could result in the articular impairments by the excessive loads from lower limb malalignment were identified.

• 한국운동역학회지
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• 제14권3호
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• pp.17-35
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• 2004

The purpose of this study is to explain developmental process of gait via angle-angle diagram to understand how coordinated relationships and control change with age. Twenty four female children, from one to five years of age were the test subjects for this study, and their results were compared to a control group consisting of twenty one adult females. The Vicon 370 CCD camera, VCR, video timer, monitor, and audio visual mixer was utilized to graph the gait cycle for all test subjects. Both coordinated Intra-limb relationships, and range of motion and timing according to quadrant were explained through the angle angle diagram. Movement in the sagittal plane showed both coordinated relationships and control earlier than movement in the coronal or transverse plane. In the sagittal plane, hip and Knee coordinated relationships developed first (from one year of age.) Coordinated relationships in the Knee and ankle and hip and ankle developed next, respectively. Both hip and ankle and knee and ankle development were inhibited by the inability of children to completely perform plantar flexion during the swing and initial double limb support phases. Children appeared to compensate for this by extending at their hip joint more than adults during the third phase, final double limb support. In many cases the angle angle diagram for children had a similar shape as adult's angle angle diagram. This shows that children can coordinate their movements at an early age. However, the magnitudes and timing of children's angle angle diagrams still varied greatly from adults, even at five years of age. This indicates that even at this age, children still do not possess full control of their movements.

• 대한기계학회논문집A
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• 제34권2호
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• pp.167-174
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• 2010

본 논문에서는 사무용 의자의 틸트 동작시 요추지지 기능과 등의 미끄럼을 평가함으로써 등판 회전중심의 최적 위치를 연구하였다. 이를 위해 인체와 의자로 이루어진 수학적 모델을 이용하여 틸트 동작 시뮬레이션을 수행하였다. 착석된 인체 모델의 측면 상에서 고관절 중심을 포함한 42개의 위치에 등판 회전축 위치를 설정하고 각각 시뮬레이션을 수행하였다. 또한 등판의 회전중심이 고관절에 위치한 의자 시작품과 좌판하부에 위치한 기존의 의자에 대해 동작분석 실험도 함께 수행하였다. 시뮬레이션 결과 등판의 회전중심이 고관절 중심에 가까이 위치할수록 틸트시 요추각도 변화량과 등의 미끄럼거리는 작아졌다. 한편 실험결과 착석자의 등과 등판사이의 이격변위와 미끄럼변위는 등판의 회전중심이 고관절 위치에 설계된 시작품에서 더 작게 측정되었다. 시뮬레이션과 실험결과로부터 등판의 회전중심이 인체의 고관절 위치에 가깝게 설계되면 틸트시 착석자의 요추를 효과적으로 지지해 줄 수 있음을 알 수 있었고 이때 착석자는 보다 편안하고 건강한 착석자세를 유지할 수 있다. 이 결과는 사무용 의자에서 등판 회전축 위치의 인간공학적 설계를 위한 가이드라인을 제공한다.

• Journal of Information Processing Systems
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• 제12권2호
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• pp.196-213
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• 2016

System Architecture Evolution (SAE) with Long Term Evolution (LTE) has been used as the key technology for the next generation mobile networks. To support mobility in the LTE/SAE-based mobile networks, the Proxy Mobile IPv6 (PMIP), in which the Mobile Access Gateway (MAG) of the PMIP is deployed at the Serving Gateway (S-GW) of LTE/SAE and the Local Mobility Anchor (LMA) of PMIP is employed at the PDN Gateway (P-GW) of LTE/SAE, is being considered. In the meantime, the Host Identity Protocol (HIP) and the Locator Identifier Separation Protocol (LISP) have recently been proposed with the identifier-locator separation principle, and they can be used for mobility management over the global-scale networks. In this paper, we discuss how to provide the inter-domain mobility management over PMIP-based LTE/SAE networks by investigating three possible scenarios: mobile IP with PMIP (denoted by MIP-PMIP-LTE/SAE), HIP with PMIP (denoted by HIP-PMIP-LTE/SAE), and LISP with PMIP (denoted by LISP-PMIP-LTE/SAE). For performance analysis of the candidate inter-domain mobility management schemes, we analyzed the traffic overhead at a central agent and the total transmission delay required for control and data packet delivery. From the numerical results, we can see that HIP-PMIP-LTE/SAE and LISP-PMIP-LTE/SAE are preferred to MIP-PMIP-LTE/SAE in terms of traffic overhead; whereas, LISP-PMIP-LTE/SAE is preferred to HIP-PMIP-LTE/SAE and MIP-PMIP-LTE/SAE in the viewpoint of total transmission delay.

• 한국컴퓨터정보학회논문지
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• 제12권5호
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• pp.285-292
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• 2007

본 논문은 정형외과영역인 대퇴부에 고정하여 사용하는 금속판으로 골 고정 골절치료의 유합술 골절치료를 할 수 있도록 구성하였는데, 사용되는 치료방법은 견고하고, 안정적이며, 역동적인 생물학적 금속판으로 고정 골수강 내 고정술을 적용되도록 견고한 골접촉 곡선형 시스템을 분석하였다. 금속판은 두 가지 유형으로 장형과 단형으로 구성되고, 금속판의 굴곡이 구조적이고 기하학적으로 경성 및 강도가 고루 분포하도록 최적화 하였다. 장 플레이트의 골접촉에 따른 곡선형으로 굽힙강도는 11,000N 이고, 단 플레이트의 골접촉에 따른 곡선형으로 굽힙강도는 6,525N 이며, 금속판에 골편간 압박을 주는 인장강도는 $1573N/m^2,\;1539N/m^2$정도이다. 금속판은 곡선부와 금속판부의 두 가지 부분으로 나뉘어져 있는데, 곡선부만 있는 단형과 밑 부분의 금속판이 달려있는 장형으로 진행되며, 곡선부의 단형은 전체적인 Profile이 낮고, 금속판이 달려있는 장형은 슬리브의 일체형으로 Profile보다 약간 높아져서 있다. 본 논문의 결과로 제공되는 것은 Hip Implant의 Revision case에 있어 보완뿐만 아니라 Hip Neck Fracture 경우에 사용되었던 Compression Hip Screw의 사용이 가능할 것으로 예상된다.

• 대한인간공학회지
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• 제29권3호
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• pp.279-286
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• 2010

The purpose of this study was to compare the electromyographic(EMG) activities of trunk and hip muscles between right and left sides while subjects performed prolonged manual task in asymmetric and symmetric weight-bearing posture. Fifteen healthy male college students were recruited for this study. The subjects were asked to perform bimanual upper extremity task for 6 minutes in two different standing postures. In the symmetric weight-bearing posture, the subjects were standing with evenly distributed body weights to both legs. In the asymmetric weight-bearing posture, the subjects distributed about 90% of their body weight onto their preferred(supporting) leg and 10% of their body weight onto the opposite leg while they were standing. EMG activities of the right and left internal oblique, erector spinae, gluteus maximus, and gluteus medius were measured and normalized as % MVIC. Then the EMG data were statistically analyzed using paired t-tests. The EMG activities of all measured muscles were not significantly different between the right and left side in the symmetrical weight-bearing posture(p>0.05). However, the EMG of the supporting side internal oblique was significantly lower than the opposite side(p<0.05), and the EMG of the erector spinae, gluteus maximus, and gluteus medius were significantly greater on the supporting side(p<0.05). The results of this study support that unbalanced use of right and left muscle possibly causes the changes in muscle length which results in asymmetry of trunk and hip muscles. Furthermore, the uneven weight support onto right and left legs will cause a distortion of viscoelastic ligaments around hip and sacroiliac joints in the long run. Further studies to determine the effect of various manual tasks on the trunk and hip muscles as well as the effect of asymmetrical weight-bearing standing posture on hip and back muscle fatigue may be required.

• 한국전문물리치료학회지
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• 제9권3호
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• pp.23-37
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• 2002

This study examined the muscle recruitment order during extension of the hip joint in normal subjects, and evaluated whether the external support obtained from wearing a lumbosacral corset had an effect on muscle recruitment leading to increased lumbar stability. The subjects were 40 normal adults (32 male, 8 female) with no history of low back pain and no pathological findings in the nervous or musculoskeletal systems. All subjects extended their hip joints under 3 positions (prone, sidelying, standing). During extension, the onsets of contraction of the rectus abdominis, gluteus maximus, and semitendinosus muscles were measured. Electromyographic activity was measured using a surface electrode, and the muscle contraction onset time was designated as the point exceeding a threshold of 25 ms, using a mean plus twice of the standard deviation. To compare the average order of muscle contraction onset time, a Freedman two-way analysis of variance by ranks was used. The relative difference between muscle contraction onset time wearing and not wearing a lumbosacral corset was measured using a paired t-test. A difference in the average muscle contraction onset order for the rectus abdominis, gluteus maximus, and semitendinosus muscles was observed (p<.05) among three positions. However, wearing a lumbosacral corset did not. change the contraction order. In addition, wearing a lumbosacral corset produced a significant difference (p<.05) in the relative onset time between the rectus abdominis and gluteus maximus in the standing position, but no difference was observed for the other muscles or positions. In the future, patients suffering from low back pain should be compared with normal subjects to determine the effectiveness of a lumbosacral corset in changing muscle recruitment order.

• 한국화재소방학회논문지
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• 제34권2호
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• pp.103-109
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• 2020

이 연구는 기본심폐소생술 교과목을 이수한 응급구조과 학생을 대상으로 수행자 엉덩관절 각도에 따라 기본심폐소생술의 질이 향상되는지 알아보고자 하였다. 기본심폐소생술 중 엉덩관절 각도에 따른 기본심폐소생술 질(가슴압박 깊이, 완전한 이완, 압박속도 등)을 측정하기 위해 SimPad SkillReporter와 Resusci Anne® QCPR®을 이용하여 비교 분석하였고, 2015 AHA Guideline 따랐으며, 가슴압박과 인공호흡의 비율은 30:2로 5주기 시행하였다. 실험군과 대조군의 일반적인 자세에서는 엉덩관절 각도, 인공호흡정도, 가슴압박 깊이, 가슴압박 속도, 가슴압박 이완, 가슴압박 정확도, 가슴압박 중단시간(Hands off time), 가슴압박 적용시간 비율은 큰 차이를 보이지 않았다(p > 0.05). 엉덩관절 각도를 90도로 유지하는 기본심폐소생술은 유지하지 않았을 때와 큰 차이는 없었으나, 적정깊이와 100% 이완에서는 좋은 결과를 보여 주어 보다 더 나은 심폐소생술 질 향상을 기대할 수 있을 것이다.

• The Journal of Korean Physical Therapy
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• 제18권4호
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• pp.27-40
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• 2006

Purpose: This study was to investigate the effect of an arm sling on gait with hemiparesis. Methods: Fifteen patients(8 male, 7 female) with hemiparesis participated in this study and walked self-selected speed over 10m walkway, randomly without arm sling, with Single strap hemisling and Rolyan humeral cuff sling. It were filmed by 5 video camera and used with 3-dimensional motion analyzer system. The following gait variables were analyzed: temporo-spatial parameters, kinematic parameters. Results: In the comparison of temporo-spatial parameters each trial, walking velocity and single support time on affected side was significantly increased and step length on affected side, step length asymmetry ratio, single support time asymmetry ratio was significantly decreased in the Single strap hemisling and Rolyan humeral cuff sling. In the comparison of kinematic parameters each trial, maximal angle of the hip flexion on affected side was significantly increased in the Single strap hemisling and Rolyan humeral cuff sling and maximal angle of the knee flexion on affected side was significantly increased in the Rolyan humeral cuff sling and maximal angle of the ankle dorsiflexion on affected side was significantly increased in the Single strap hemisling. Conclusion: An arm sling improved walking velocity and decreased asymmetry and increased maximal angle of hip, knee, ankle flexion on affected side with hemiparesis caused by stroke.

• 대한의용생체공학회:의공학회지
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• 제18권1호
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• pp.71-78
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• 1997

Kinematic and kinetic studies were performed to investigate the walking characteristics on a treadmill with various slopes at the same speed of 1.25m/sec. Six different slopes of the treadmill were selected . -4%(-$2.3^{\circ}$), 0%($0^{\circ}$), 5%($2.9^{\circ}$), 10%($5.7^{\circ}$), 15%($8.6^{\circ}$), and 20%($11.3^{\circ}$). With increased slopes of the treadmill, both hip and knee flexion angles significantly increased at initial contact, and the maximum hip flexion during swing phase and the maximum knee flexion during stance phase also significantly increased Ankle dorsiflexion angle at initial contact and the maximum dorsiflexion increased with increased slopes. However, the maximum plantarflexion in early swing was slightly reduced with increased slopes. Hip extension in late stance and the maximum knee flexion in early swing was not changed sigilificantly with increased slopes. As for the vertical ground reaction force, compared to the yond level walking, both the first and the second peak forces increased, but the mid-support force decreased.