• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.4
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• pp.247-253
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• 2005

This study investigated the effects on foot and ankle roll-over characteristics according to different heel heights during walking. Fifteen female volunteers who have neither musculoskeletal nor foot problems were participated in gait analyses, wearing four different pairs of shoes in different heel heights. To obtain roll-over shape of foot/ankle complex, we used trajectories of knee and ankle joints as well as the renter of pressure between initial contact and opposite initial contact. Results revealed that the entire roll-over shape moved distally as the heel height increased but roll-over characteristics showed uniformly with different heel heights. In addition, we found that nondisablea persons automatically adapted to their foot/ankle complex to varying heel heights within 6cm, by moving the origin of roll-over shape distally to maintain roll-over characteristics. However, since the balance of the gait only by the ankle joint could not be achieved beyond the heel height of 6cm, compensations at the knee and the hip joints occurred simultaneously. Roll-over characteristics in human walking would provide simpler and wider understanding of human walking, and furthermore could be applied to the wide understanding of prosthetics and orthotics of the lower extremity as well as orthopaedic shoes.

• The Korean Journal of Pain
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• v.34 no.3
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• pp.250-261
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• 2021

Background: Complex regional pain syndrome type I (CRPS-I) consists of disorders caused by spontaneous pain or induced by some stimulus. The objective was to verify the effects of photobiomodulation (PBM) using 830 nm wavelength light at the affected paw and involved spinal cord segments during the warm or acute phase. Methods: Fifty-six mice were randomized into seven groups. Group (G) 1 was the placebo group; G2 and G3 were treated with PBM on the paw in the warm and acute phase, respectively; G4 and G5 treated with PBM on involved spinal cord segments in the warm and acute phase, respectively; G6 and G7 treated with PBM on paw and involved spinal cord segments in the warm and acute phase, respectively. Edema degree, thermal and mechanical hyperalgesia, skin temperature, and functional quality of gait (Sciatic Static Index [SSI] and Sciatic Functional Index [SFI]) were evaluated. Results: Edema was lower in G3 and G7, and these were the only groups to return to baseline values at the end of treatment. For thermal hyperalgesia only G3 and G5 returned to baseline values. Regarding mechanical hyperalgesia, the groups did not show significant differences. Thermography showed increased temperature in all groups on the seventh day. In SSI and SFI assessment, G3 and G7 showed lower values when compared to G1, respectively. Conclusions: PBM irradiation in the acute phase and in the affected paw showed better results in reducing edema, thermal and mechanical hyperalgesia, and in improving gait quality, demonstrating efficacy in treatment of CRPS-I symptoms.

• Journal of Electrical Engineering and Technology
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• v.10 no.6
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• pp.2368-2375
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• 2015

To accommodate various navigational commands, a humanoid should be able to change its walking motion in real time. Using the modifiable walking pattern generation (MWPG) algorithm, a humanoid can handle dynamic walking commands by changing its walking period, step length, and direction independently. If the humanoid is given a command to perform an infeasible movement, the algorithm substitutes the infeasible command with a feasible one using binary search. The feasible navigational command is subsequently translated into the desired center-of-mass (CM) state. Every sample time CM reference is generated using a zero-moment-point (ZMP) variation scheme. Based on this algorithm, various complex walking patterns can be generated, including backward and sideways walking, without detailed consideration of the feasibility of the navigational commands. In a previous study, the effectiveness of the MWPG algorithm was verified by dynamic simulation. This paper presents experimental results obtained using the small-sized humanoid robot platform DARwIn-OP.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.11 s.176
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• pp.182-189
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• 2005

The human knee joint is the intermediate joint of the lower limb that is the largest and most complex joint in the body. Understanding of joint-articulating surface motion is essential for the joint wear, stability, mobility, degeneration, determination of proper diagnosis and so on. However, many studies analyzed the passive motion of the lower limb because of the skin marker artefact and some studies described medial and lateral condyle of a femur as a simple sphere due to the complexity of geometry. Thus, in this paper, we constructed a three-dimensional geometric model of the human knee from the geometry of its anatomical structures using non-uniform B-spline surface fitting as a study for the kinematic analysis of more realistic human knee model. In addition, we developed and verified 6-DOF contact model of the human knee joint using $C^2$ continuous surface of the inferior region of a femur, considering the relative motion of shank to thigh during locomotion.

• Journal of Electrical Engineering and Technology
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• v.11 no.3
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• pp.751-758
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• 2016

The modifiable walking pattern generation (MWPG) algorithm can handle dynamic walking commands by changing the walking period, step length, and direction independently. When an infeasible command is given, the algorithm changes the command to a feasible one. After the feasibility of the navigational command is checked, it is translated into the desired center of mass (CM) state. To achieve the desired CM state, a reference CM trajectory is generated using predefined zero moment point (ZMP) functions. Based on the proposed algorithm, various complex walking patterns were generated, including backward and sideways walking. The effectiveness of the patterns was verified in dynamic simulations using the Webots simulator.

• Journal of Mechanical Science and Technology
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• v.18 no.12
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• pp.2069-2079
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• 2004

This paper represents the description of a complex mathematical model of biomechanical interaction for human-rifle system during shooting. The model is developed by finite element method using bar elements. And three typical shooting positions, i.e. standing, kneeling and prone are used. Characteristics of interior/exterior ballistics and behaviors of human-rifle system are evaluated by this model, which takes into account the influence of environment, bullet, powder, barrel geometry parameters and anthropological parameters. The results of this study can be applied to anthropology, biomechanics, medical science, gait analysis, interior ballistics and exterior ballistics.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.344-351
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• 2014

In order to accomplish complex navigational commands, humanoid robot should be able to modify its walking period, step length and direction independently. In this paper, a novel walking pattern generation algorithm is proposed to satisfy these requirements. Modification of the walking pattern can be considered as a transition between two periodic walking patterns, which follows each navigational command. By assuming the robot as a linear inverted pendulum, the equations of motion between ZMP(Zero Moment Point) and CM(Center of Mass) state is easily derived and analyzed. After navigational command is translated into the desired CM state, corresponding CM motion is generated to achieve the desired state by using simple ZMP functions. Moreover, when the command is not feasible, feasible command is alternated by using binary search algorithm. Subsequently, corresponding CM motion is generated. The effectiveness of the proposed algorithm is verified by computer simulation.

• Proceedings of the KAIS Fall Conference
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• 2010.05b
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• pp.735-738
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• 2010

본 연구는 관절가동범위 및 근력강화운동, 반복적인 과제-지향적 활동으로 구성된 복합운동프로그램을 뇌졸중 환자에게 2년 4개월 동안 적용하여 상지 기능 및 균형 능력에 미치는 효과를 알아보고자 하였다. 연구대상자는 뇌졸중으로 인한 좌측 편마비 증상을 보이는 68세 여성으로 매 회기 1시간씩, 주 3회, 2년 4개월 동안 복합운동프로그램을 수행하였다. 대상자의 상지 기능은 브론스트롬의 손 회복 단계와 상지 회복단계, Fugl-Meyer Assessment of Motor Function, 뇌졸중 상지기능검사로, 균형 능력은 Tinetti Gait & Balance Scale로 평가하였다. 연구 결과 대상자의 상지 기능과 균형 능력이 유지 및 향상 되었다. 이를 통하여 만성 뇌졸중 환자에서 상지 및 균형 능력의 유지 및 증진을 위한 지속적인 복합 운동프로그램 수행의 유효성을 확인할 수 있었다.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3089-3091
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• 1999

To control IWR-III Biped Waking Robot, those complex modules are necessary that concurrent control multi-axes servo motors, PID & Feedforward gain tuning, initial value calibration, display current status of system, user interface for emergency safety and three-dimensional rendering graphic visualization. It is developed for various-type gait $data^{[1]}$ and for control modes (i.e open/closed loop and pulse/velocity/torque control) that Integrated Control Enviroment with GUI( Graphic User Interface) consist of time-buffered control part using MMC (Multi-Motion Controller) and 3D simulation part using DirectX graphic library.

• Journal of Korean Foot and Ankle Society
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• v.25 no.2
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• pp.80-88
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• 2021

Chronic Achilles tendon rupture is likely to result in functional impairment in gait and sports activity. The presence of a large defect secondary to retraction of the tendon ends, atrophy of the calf muscles, and vulnerable vascularity of the soft tissue envelope make it a challenging problem to treat. Surgical reconstruction aims to restore the length and tension of the gastrocnemius-soleus complex. Various surgical treatment options have been described, depending on several factors, including residual gap size after scar tissue removal, remaining tissue quality, and vascularity. Despite good results being reported, there is a lack of high-level, evidence-based clinical guidelines available to select the first-line surgical procedure. This paper overviews the current available surgical options for patients with chronic Achilles tendon rupture.