• Steel and Composite Structures
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• v.26 no.2
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• pp.227-239
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• 2018

Integral abutment bridges (IABs) have no joint across the length of bridge and are therefore also known as jointless bridges. IABs have many advantages, such as structural integrity, efficiency, and stability. More importantly, IABs have proven to be have both low maintenance and construction costs. However, due to the restraints at both ends of the girder due to the absence of a gap (joint), special design considerations are required. For example, while replacing the deck slabs to extend the service life of the IAB, the buckling strength of the steel girder without a deck slab could be much smaller than the case with deck slab in place. With no deck slab, the addition of thermal expansion in the steel girders generates passive earth pressure from the abutment and if the applied axial force is greater than the buckling strength of the steel girders, buckling failure can occur. In this study, numerical simulations were performed to estimate the buckling strength of typical steel girders in IABs. The effects of girder length, the width of flange and thickness of flange, imperfection due to fabrication and construction errors on the buckling strengths of multiple and single girders in IABs are studied. The effect of girder spacing, span length ratio (for a three span girder) and self-weight effects on the buckling strength are also studied. For estimation of the reaction force of the abutment generated by the passive earth pressure of the soil, BA 42/96 (2003), PennDOT DM4 (2015) and the LTI proposed equations (2009) were used and the results obtained are compared with the buckling strength of the steel girders. Using the selected design equations and the results obtained from the numerical analysis, equations for preventing the buckling failure of steel girders during deck replacement for maintenance are presented.

• The Journal of Korean Physical Therapy
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• v.17 no.4
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• pp.457-467
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• 2005

Physiotherapyists frequently use manipulative therapy technique to treat dysfunctionand pain resulting from ankle sprain. Despite the high prevalence of lateral ankle ligament injuries, few studies are available indicating any physical associations with the development of lateral ankle ligament injuries, or information of treatment for lateral ankle ligament injuries. To investigate the effect of passive joint mobilization, the anteroposterior glide on the talus, on increasing weight-bearing dorsiflexion, single support time and VAS. Sixty lateral ankle ligament injuries (grade I and grade II) aged between 17 and 27 years (mean age 21) were recruited. Subjects were randomly assigned to 1 of 2 treatment groups. The control group received a protocol of rest, ice, compression, and elevation (RICE) and massage. The experimental group received the anteroposterior mobilization, using a force that avoided incurring any increase in pain, in addition to the RICE protocol. Subjects in both groups were treated every second day for a maximum of 2 weeks or until the discharge criteria were met, and all subjects were given a home program of continued RICE application. Outcomes were measured after each treatment. The results showed that the experimental group than the control group. Weight-bearing dorsiflexion (F=7.640, P<0.05), single support time (F=85.532, P<0.05) and VAS (F=10.610, P<0.050). Between-groups differences were observed as; experimental group is increased weight-bearing dorsiflexion, single support time and reduced VAS.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.7
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• pp.2468-2474
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• 2010

The purpose of this study was to investigate the effects of taping therapy and passive range of motion exercises for the elderly aged 65 above with shoulder pain and limited of range of motion. This study was a nonequivalent control group pretest-posttest design. Data were collected about shoulder pain, range of motion, hand dexterity from 40 of elderly(exp.:20, con.:20) in B city from August to September, 2009. Collected data were analyzed using SPSS Win 12.0. Shoulder pain was significantly decreased. Range of motion which was flexion, extension, abduction, horizontal abduction. and hand dexterity were significantly increased in the taping group and PROM group. Shoulder pain and hand dextrity was non significantly between taping group and PROM group. Range of motion which was extension more increased taping group than PROM group. It was proven that taping therapy and PROM was effective for shoulder pain, articular range of motion and hand dexterity.

• International Journal of Contents
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• v.10 no.3
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• pp.90-95
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• 2014

The purpose of this study was to analyze the changes in muscle fatigue by using electromyography (EMG) measurements of the median frequency of shoulder muscles of patients who underwent rotator cuff repair, and to provide basic data for efficient exercise methods during rehabilitation after the repair. In the study, 24 male and 8 female patients who underwent rotator cuff repair performed continuous passive shoulder joint motion for 3 weeks and the median frequency of their shoulder muscles before and after the repair were compared using measurements by EMG. The infraspinatus, supraspinatus, and serratus anterior muscles showed significant differences in the changes in the median frequency before and after the repair. Significant differences were also found in the median frequency of the three muscles both before and after the repair. Additionally, the middle deltoid muscle had a lower median frequency than the supraspinatus muscle before the repair and the infraspinatus muscle had a lower median frequency than the middle deltoid muscle after the repair. It is expected that these results will serve as important data in developing rehabilitation exercise programs for the infraspinatus, supraspinatus, and serratus anterior muscles by compensating the middle deltoid muscle with the lowest muscle fatigue after the rotator cuff repair erase.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.810-815
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• 2004

In this paper, we propose new parallel mechanism of a 3 dimensional biped robot whose each leg is composed of two 3-dof parallel platforms linked serially. This proposed parallel mechanism is able to move freely in the man-made environment and is applied to various fields, such as medical, welfare, and so on. And a total weight of each leg is expected to be lighter than serial linked leg. One side leg consists of a 3-dof orientation platform and 3-dof asymmetric parallel platform. The former consists of three active linear actuators and seven passive joints, and the latter of two active linear actuators, one active rotational actuator and eight passive joints. Thus, there are two kinds of parallel platforms each chain's elements and active joint's positions are different for the biped robot to move freely like a serial link without the kinematics constraints. The effectiveness and the performance of the proposed parallel mechanism and locomotion trajectory are shown in computer simulations with a 12-DOF parallel biped robot.

• Earthquakes and Structures
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• v.13 no.1
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• pp.51-58
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• 2017

Passive dynamic vibration absorbers (DVAs) are often used to suppress the excessive vibration of a large structure due to their simple construction and low maintenance cost compared to other vibration control techniques. A new type of passive DVA consists of two pendulums connected with spring and dashpot element is investigated. This research evaluated the performance of the DVA in reducing the vibration response of a two degree of freedom shear structure. A model for the two DOF vibration system with the absorber is developed. The nominal absorber parameters are calculated using a Genetic Algorithm(GA) procedure. A parametric study is performed to evaluate the effect of each absorber parameter on performance. The simulation results show that the optimum condition for the absorber frequencies and damping ratios is mainly affected by pendulum length, mass, and the damping coefficient of the pendulum's hinge joint. An experimental model validates the theoretical results. The simulation and experimental results show that the proposed technique is able be used as an effective alternative solution for reducing the vibration response of a multi degree of freedom vibration system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.1
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• pp.426-445
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• 2012

Conventional rate control (RC) schemes for H.264 video coding usually regulate output bit rate to match channel bandwidth by adjusting quantization parameter (QP) at fixed full frame rate, and the passive frame skipping to avoid buffer overflow usually occurs when scene changes or high motions exist in video sequences especially at low bit rate, which degrades spatial-temporal quality and causes jerky effect. In this paper, an active content adaptive frame skipping scheme is proposed instead of passive methods, which skips subjectively trivial frames by structural similarity (SSIM) measurement between the original frame and the interpolated frame via motion vector (MV) copy scheme. The saved bits from skipped frames are allocated to coded key ones to enhance their spatial quality, and the skipped frames are well recovered based on MV copy scheme from adjacent key ones at the decoder side to maintain constant frame rate. Experimental results show that the proposed active SSIM-based frameskip scheme acquires better and more consistent spatial-temporal quality both in objective (PSNR) and subjective (SSIM) sense with low complexity compared to classic fixed frame rate control method JVT-G012 and prior objective metric based frameskip method.

• Journal of the Korean Society of Physical Medicine
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• v.8 no.4
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• pp.619-625
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• 2013

PURPOSE: The purpose of this study was to determine the effects of muscle fatigue on knee joint position sense in the young, elderly adults, and stroke patients. METHODS: The subjects were recruited into three groups; young group(YG)(N=15), elderly group(EG)(N=15), and stroke group(SG)(N=15). Exercise-induced fatigue was achieved by repeated active exercise 60 times on an angle at 10 to 100 degrees of the knee joint with an angle speed of $120^{\circ}/s$, with three sets for 15 minutes. Evaluation was performed for determination of repositioning error using passive angle repositioning (PAR) and active angle repositioning (AAR). RESULT: Regarding the error score for the knee joint position sense in both the baseline and muscle fatigue, significant increases were observed between the YG and EG (p<.05), and between the EG and SG (p<.01), and between YG and SG (p<.05) in the PAR, YG and SG (p<.05) in the AAR. CONCLUSION: In particular, the results of this study indicate that management and intervention for elderly adults and stroke patients can result in improvement of proprioception.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.9 no.2
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• pp.13-23
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• 2003

본 연구의 목적은 손 기능에 문제가 있는 환자들을 중심으로 splint의 효과를 알아보기 위한 기초조사로써 2명의 환자를 제주 한마음병원(Case1, 2)에서 2001년 6월부터 11월까지 조사하였다. 2명의 환자는 다음과 같다. i) 사례 1 : 뇌성마비 아동(4세, 남, 오른손)으로 한쪽 손목과 엄지손가락에 강직으로 인하여 잡기 기능에 제한이 있는 편마비 아동이다. ii) 사례 2 : 전기화상(56세, 남, 왼손)으로 4-5번째 손가락의 M.P joint와 I.P joint에 관절운동 제한으로 완전하게 주먹을 질 수가 없다. 연구를 위하여 손 기능의 평가는 표준화가 되어있는 Jebsen-hand function test, Total passive Motion(TPM)을 사용하였으며, 환자들의 만족도를 알아보기 위해서는 Canadian Occupational Performance Measure(COPM)을 사용하였다. i) 사례 1 : 두 가지 splint를 적용하였다. 즉 낮 동안에는 splint 1, 밤 동안에는 splint 2를 6시간 이상 착용하도록 하였으며 작업치료는 시행하지 않았다. ii) 사례 2 : 이 환자에게는 작업치료가 끝나는 동시에 splint. 3을 6시간 이상 착용하도록 하였으며, M.P joint와 I.P joint의 관절 변화를 조절하도록 특별히 고안된 splint를 적용하였다. 그 결과 사례 1의 Jebsen-hand function test시 초기에는 측정을 할 수가 없었으나, splint착용 후 크고 가벼운 물건 옮기기(44.15), 크고 무거운 물건 옮기기(42.66), 적목쌓기(44.63), 먹기 흉내내기(54.47) 등에서 처음 동작만 도와주면 측정이 가능할 수 있도록 진전을 보였다(그래프1), 사진(착용 전과 착용 후). 사례 2의 경우 Jebsen-hand function test의 적목쌓기와 먹기 흉내기가 가장 높았으며, 글씨 쓰기가 가능했다. 손의 관절가동 변화에서도 splint 착용전의 측정치와 착용 후 관절 가동 범위의 변화 폭이 약 $30_{\circ}$이를 보여주었다(그래프 2), (그래프3). 결론적으로 손 기능 회복에 직접적인 재활 치료뿐만 아니라, 치료 후에도 splint를 착용하여 가정에서도 계속적인 치료가 될 수 있도록 하는 것이 손의 기능회복에 도움이 됨을 알 수 있었다. 그러므로 각 환자의 문제점을 파악하여 적절한 splint를 제작해 줄 필요가 있다고 사료된다. 이 기초조사를 시작으로 하여 더 많은 환자들을 대상으로 splint가 손 기능 회복에 어떠한 영향을 미치는지 그 효과에 대하여 계속적인 연구가 필요할 것이다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.8
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• pp.505-510
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• 2017

This paper presents a low-cost robotic device for shoulder rehabilitation, which is capable of treating various shoulder disabilities. A 3-DOF passive shoulder joint tracking module was designed to allow for translational motion of the shoulder joint center during arm swing, which is essential for natural shoulder movement. The weight of the user's arm and the device were compensated for by springs, to enable gravity-free shoulder motion. In order to reduce the device's cost, only one actuator was used, which can be aligned with the user's shoulder joint in various orientations. The device is capable of implementing five representative shoulder motions, including flexion/extension, abduction/adduction, horizontal abd/adduction, internal/external rotation, and oblique raise. The proposed low-cost shoulder rehabilitation robot is expected to provide effective rehabilitation for patients with various shoulder impairments.