• Structural Engineering and Mechanics
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• 제54권5호
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• pp.937-953
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• 2015

This paper investigates the load model for single footfall trace of human walking. A large amount of single person walking load tests were conducted using the three-dimensional gait analysis system. Based on the experimental data, Fourier series functions were adopted to model single footfall trace in three directions, i.e. along walking direction, direction perpendicular to the walking path and vertical direction. Function parameters such as trace duration time, number of Fourier series orders, dynamic load factors (DLFs) and phase angles were determined from the experimental records. Stochastic models were then suggested by treating walking rates, duration time and DLFs as independent random variables, whose probability density functions were obtained from experimental data. Simulation procedures using the stochastic models are presented with examples. The simulated single footfall traces are similar to the experimental records.

• 대한물리의학회지
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• 제12권1호
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• pp.35-42
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• 2017

PURPOSE: The purpose of this study was to examine the effects of treadmill gait training in an adjusted position from the functional training system on the gait and balance of chronic stroke patients. METHODS: Thirty chronic stroke patients were randomly assigned to either the experimental group, who received treadmill gait training in an adjusted position, or the control group, who received regular treadmill gait training. Both groups underwent a 30-minute comprehensive rehabilitation treatment before receiving an additional 20-minute treadmill gait training. This routine was repeated five times a week for four weeks. To measure the difference before and after training in walking and balance, patients were scored on the following: 10 m walking test (10 MWT), 6 minute walking distance (6 MWD), timed up and go test (TUG), and static standing balance test (stability index). RESULTS: While post-training scores of 10 MWT, 6 MWD, TUG, and stability index for both groups increased significantly compared with pre-training (p<.05), the experimental group showed greater improvement than the control group (p<.05). The scores of the experimental group increased significantly by 9% in the 10 MWT, 11% in 6 MWD, 13% in the TUG, 8% in the stability Index (eye opened), and 10% in the stability index (eye closed). CONCLUSION: Treadmill gait training in an adjusted position from the functional training system would be a useful gait training method to improve walking and balance of chronic stroke patients.

• 재활복지공학회논문지
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• 제11권1호
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• pp.81-89
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• 2017

본 논문은 대퇴절단 환자의 다양한 환경에서의 보행을 가능하게 하는 지능형 의족의 보행노면 및 보행단계 판별 기법을 제안한다. 제안하는 보행모드 변경 기법은 스트레인게이지 센서 만으로 보행노면 및 보행단계 판별이 가능한 단일 센서 기반의 알고리즘으로 기존 지능형 의족의 다중센서 기반 알고리즘의 단순화와 의족 시스템의 저가화가 가능하게 고안하였다. 보행노면 판별 알고리즘을 위해 정상인의 보행 중 발생하는 지면반발력의 특징을 분석하여 보행단계 세분화와 보행노면 검출 조건을 정의하였고, 대퇴절단 환자와 유사한 환경에서의 보행 실험을 위해 보행분석 장치를 제작하였다. 정의된 검출 조건과 제작된 기구를 통해 논문의 효용성 검증을 진행하였으며, 정상인 대상의 실험결과 단일 센서 기반 알고리즘의 정확도는 약 95%를 나타냈다. 제안하는 단일 센서 기반의 알고리즘을 통해 지능형 의족 시스템의 저가화가 가능할 것으로 판단되며 사용자가 직접 보행노면 상태를 파악하고 보행모드를 전환하는 수동 보행모드 변경 방식에서 벗어나 의족이 현재 보행 노면 상태를 파악하고 상황에 맞는 보행모드를 전환하는 자동보행 모드 변경이 가능할 것으로 확인되었다.

• 한국산학기술학회논문지
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• 제14권12호
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• pp.6237-6245
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• 2013

본 연구는 리듬청각자극을 이용한 후방 보행 훈련이 뇌졸중 환자의 보행과 균형에 미치는 영향을 알아보기 위한 것으로 21명의 뇌졸중 환자를 무작위로 세 집단으로 나누었고, 실험군I은 전방 보행 훈련 군, 실험군II은 후방 보행 훈련군, 실험군III은 리듬청각자극을 이용한 후방 보행 훈련 군으로 집단마다 7명씩 실험하였다. 실험은 3주간 주 5회 30분씩 실시하였으며 실험 전과 3주간의 실험 후에 각 실험군의 10m 보행 검사, 일어나 걸어가기 검사, 기능적 팔 뻗기 검사를 하였고, biodex gait trainer 2를 사용하여 활보장과 보장비대칭 비를 측정하였다. 연구의 결과 각 군내의 실험 전 후 비교에서 보행속도, 보행대칭성, 균형에 유의한 차이를 보였고(p<.05), 변화량을 비교했을 때 모두 유의한 차이를 보였으며(p<.05), 보행속도, 보행대칭성과 균형에서는 실험군III, 실험군II, 실험군I 순으로 효과적이였고, 활보장에서는 실험군II와 실험군III이 실험군I보다 효과적이였다. 이 결과를 통하여 뇌졸중 환자를 대상으로 보행 운동을 실시할 때 리듬청각자극을 이용한 후방 보행 훈련이 보행속도, 보행대칭성과 균형의 향상에 있어서 효과적인 방법임을 알 수 있다.

• PNF and Movement
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• 제21권1호
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• pp.27-35
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• 2023

Purpose: Hallux valgus (HV) is one of the most common chronic foot disorders, occurring when the first toe deviates laterally toward the other toe. HV impairs muscle strength and affects gait function (postural sway and gait speed). Thus, this study aims to investigate using the FDM system the effect of wearing braces on gait while wearing a virtual reality (VR) device. Methods: This study was conducted on 28 healthy adults with HV of 15 degrees or more. To compare differences in walking, depending on whether a toe brace can be worn, the subject walked without wearing anything, walked after wearing the VR device, and walked after wearing the VR device and the toe brace, and the FDM system was used for the gait ability measurement analysis. Results: As a result of a one-way repeated analysis of variance, the walking speed-related variables (cadence, velocity, etc.) in the HV group were higher during comfortable walking. In addition, walking while wearing a VR device and walking while wearing a VR device and a toe brace demonstrated more significant values in terms of six gait parameters (double stance phase, loading response, stage, stage, stage, and stage). The maximum pressure of the forefoot was significantly reduced when walking while wearing a VR device and a toe brace compared to comfortable walking, but in all variables, there was no statistically significant difference between walking while wearing a VR device and walking while wearing a VR device and a toe brace. Conclusion: Orthosis with a VR device during gait (OVG) and gait with a VR device (GVR) affect gait in HV patients. However, there was no significant difference between GVR and OVG. Thus, it is necessary to conduct experiments on various HV angles and increase the duration of wearing the toe brace.

• 한국정밀공학회지
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• 제19권7호
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• pp.43-50
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• 2002

This paper presents the new gait implementation of a biped robot with smooth walking using 3-dimensional continuous trunk motion and kick action of ankle joints. Trajectory generation ova trunk is performed not on a unit gait but on a whole walking interval. In applying kick action such as heel-touch or toe-off, varying coordinate system was employed for the simplification of the kinematic analysis. Desired ZMP (zero moment point) is also changed to implement the efficient kick action. As a result, balancing motion of the proposed gait was much more decreased than that of conventional one. Moreover, robot\\`s walking behavior is very smooth, natural and similar to the pace of a human. The walking experiment system is composed of eight AC servo motors and a DSP controller. The walking simulation and the experimental results are shown using the proposed new walking algorithm.

• 대한물리의학회지
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• 제12권2호
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• pp.21-31
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• 2017

PURPOSE: The purpose of this study was to identify whether backward walking exercise was more effective than conventional physical therapy for balance and gait in hemiplegic stroke patients. METHODS: Eighteen patients with chronic stroke were randomly assigned to the experimental (n=9) or control (n=9) group. The experimental and control group performed backward walking exercise and conventional physical therapy, respectively, for 8 weeks. Stability Index (SI) and Weight Distribution Index (WDI) during standing were assessed using the Tetrax Balance System. The Timed Up and Go (TUG) test and Korean version of the Berg Balance Scale (K-BBS) were used to evaluate balance and fall risk. Walking speed, stride length, and step length on the affected side were measured using the 10-Meter Walk and ink foot printing tests. Wilcoxon signed-rank and Mann-Whitney U tests were used for within- and between- group comparisons, respectively. RESULTS: The experimental group showed significantly higher changes in SI (p<.01), WDI (p<.01), TUG (p<.001), and BBS score (p<.001) following intervention compared with the control group. The experimental group also showed significantly greater improvements in walking speed (p<.01), stride length (p<.001), and step length on the affected side (p<.001) after intervention compared with the control group. CONCLUSION: Backward walking exercise is an effective intervention to improve balance and gait in hemiplegic stroke patients.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권11호
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• pp.2690-2701
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• 2013

Humans are able to recognize small number of people they know well by the way they walk. This ability represents basic motivation for using human gait as the means for biometric identification. Such biometric can be captured at public places from a distance without subject's collaboration, awareness or even consent. Although current approaches give encouraging results, we are still far from effective use in practical applications. In general, methods set various constraints to circumvent the influence factors like changes of view, walking speed, capture environment, clothing, footwear, object carrying, that have negative impact on recognition results. In this paper we investigate the influence of walking speed variation to different visual based gait recognition approaches and propose normalization based on geometric transformations, which mitigates its influence on recognition results. With the evaluation on MoBo gait dataset we demonstrate the benefits of using such normalization in combination with different types of gait recognition approaches.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 B
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• pp.1228-1230
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• 1996

A neural network(NN) mechanism is proposed to modify the gait of a biped robot that walks on sloping surface using sensory inputs. The robot starts walking on a surface with no priori knowledge of the inclination of the surface. By accumulating experience during walking, the robot improves its walking gait and finally forms a gait that is adapted to the surface inclination. A neural controller is proposed to control the gait which has 72 reciprocally inhibited and excited neurons. PI control is used for position control, and the neurons are trained by a reinforcement learning mechanism. Experiments of static gait learning and pseudo dynamic learning are performed to show the validity of the proposed reinforcement learning mechanism.

• 제어로봇시스템학회논문지
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• 제21권6호
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• pp.553-559
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• 2015

The purpose of this research is to develop a gait assistive device to enhance the gait stability and training efficiency of stroke patients. The configuration of this device is mainly composed of a motored wheel and a single cane whose lower end is attached to a motored wheel frame. A patient can feel haptic information from continuous ground contact from the wheel while walking through the grip handle. In addition, the wheeled cane can avoid using excessive use of the patient's upper limb for weight support and motivate the patient to use a paralyzed lower limb more actively. Moreover, the proposed device can provide intuitive and safe user interaction by integrating a force sensor and a tilt sensor equipped to the cane frame, and a switch sensor at the cane's handle. The admittance control has been implemented for the patient to change the walking speed intuitively by using the interaction forces at the handle. A hemi-paretic stroke patient participated in the walking assistive experiments as a pilot study to verify the effectiveness of the proposed haptic cane system. The results showed that the patient could improve walking speed and muscle activations during walking with a constant speed mode of the haptic cane. Moreover, the patient could maintain the preferred walking speeds and gait stability regardless of the magnitude of resistance forces with the admittance control mode of the haptic cane. The proposed robotic gait assistive device with a simple and intuitive mechanism can provide efficient gait training modes to stroke patients with high possibilities of widespread utilizations.