• Journal of the Korea Concrete Institute
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• v.23 no.6
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• pp.731-740
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• 2011

Provisions for the redistribution of negative moments in KCI 2007 and ACI 318-08 use a method for continuous flexural members subjected to uniformly-distributed gravity load. Moment redistributions and plastic rotations in beams of reinforced concrete moment frames subjected to lateral load differ from those in continuous flexural members due to gravity load. In the present study, a quantitative relationship between the moment redistribution and plastic rotation is established for beams subjected to both lateral and gravity loads. Based on the relationship, a design method for the redistribution of negative moments is proposed based on a plastic rotation capacity. The percentage change in negative moments in the beam was defined as a function of the tensile strain of re-bars at the section of maximum negative moment, which is determined by a section analysis at an ultimate state using KCI 2007 and ACI 318-08. Span, reinforcement ratio, cracked section stiffness, and strain-hardening behavior substantially affected the moment redistribution. Design guidelines and examples for the redistribution of the factored negative moments determined by elastic theory for beams under lateral load are presented.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.7
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• pp.1709-1719
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• 1995

The primary objective of the paper is to obtain the basic information of the natural convection of a stratified with various parametric conditions related to rotating speed, temperature and concentration gradient. For the purpose of it, experiments are performed in a stably stratified salt-water solution with lateral heating in a stationary or rotating annulus. The experiment covers the ranges of Ar=2, Le=100, R $a_{\ta}$=2 10$^{5}$ and Ta=0, 10$^{5}$ - 2.5*10$^{8}$ . Many interesting flow phenomena are observed and rotation effects are examined. Particularly as Taylor number increases (rotation increases) at a given R $a_{\ta}$, the generation of rolls at hot wall is inhibited and the formation and merging process of layers are delayed.

• Clinics in Shoulder and Elbow
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• v.27 no.1
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• pp.59-71
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• 2024

Background: Restoration of external (ER) and internal rotation (IR) after Grammont-style reverse shoulder arthroplasty (RSA) is often unreliable. The purpose of this systematic review was to evaluate the influence of RSA medio-lateral offset and subscapularis repair on axial rotation after RSA. Methods: We conducted a systematic review of studies evaluating axial rotation (ER, IR, or both) after RSA with a defined implant design. Medio-lateral implant classification was adopted from Werthel et al. Meta-analysis was conducted using a random-effects model. Results: Thirty-two studies reporting 2,233 RSAs were included (mean patient age, 72.5 years; follow-up, 43 months; 64% female). The subscapularis was repaired in 91% (n=2,032) of shoulders and did not differ based on global implant lateralization (91% for both, P=0.602). On meta-analysis, globally lateralized implants achieved greater postoperative ER (40° [36°-44°] vs. 27° [22°-32°], P<0.001) and postoperative improvement in ER (20° [15°-26°] vs. 10° [5°-15°], P<0.001). Lateralized implants with subscapularis repair or medialized implants without subscapularis repair had significantly greater postoperative ER and postoperative improvement in ER compared to globally medialized implants with subscapularis repair (P<0.001 for both). Mean postoperative IR was reported in 56% (n=18) of studies and achieved the minimum necessary IR in 51% of lateralized (n=325, 5 cohorts) versus 36% (n=177, 5 cohorts) of medialized implants. Conclusions: Lateralized RSA produces superior axial rotation compared to medialized RSA. Lateralized RSA with subscapularis repair and medialized RSA without subscapularis repair provide greater axial rotation compared to medialized RSA with subscapularis repair. Level of evidence: 2A.

• Journal of the Korean Society of Radiology
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• v.12 no.1
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• pp.115-122
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• 2018

The success of the total hip arthroplasty is revealed as initial stability, range of motion, and long term pain, etc. Depending upon choice of implantation options such as femoral neck offset, diameter of the femoral head, the lateral opening tilt. Especially the impingement between femoral head component and acetabular cup limits the range of motion of the hip. In this sense, estimation or evaluation of the range of motion before and after the total hip arthroplasty is important. This study provides the details of a computer simulation technique for the hip range of motion of intact hip as well as arthroplasty. The suggested method defines the hip rotation center and rotation axes for flexion and abduction, respectively. The simulation uses CT-based reconstructed 3D models and an STL treating software. The abduction angle of the hip is defined as the superolateral rotation angle from sagittal plane. The flexion angle of the hip is defined as the superoanterior angle from the coronal plane. The maximum abduction angle is found as the maximum rotation angle by which the femoral head can rotate superolaterally about the anterior-posterior axis without impingement. The maximum flexion angle is found as the maximum rotation angle by which the femoral head can rotate superoanteriorly about the medial-lateral axis without impingement. Compared to the normal hip, the total hip replacement hip showed decreased abduction by 60 degrees and decreased flexion by 4 degrees. This measured value implies that the proposed measurement technique can make surgeons find a modification of increase in the femoral neck offset or femoral head, to secure larger range of motion.

• PNF and Movement
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• v.19 no.1
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• pp.1-8
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• 2021

Purpose: The purpose of this study was to determine how the position of tibial rotation affects peak force and hamstring muscle activation during isometric knee flexion in healthy women. Methods: Seventeen healthy women performed maximum isometric knee flexion at 30˚ with three tibial rotation positions (tibial internal rotation, neutral position, and tibial external rotation). Surface electromyographic (EMG) activity was recorded from the medial hamstring (MH) and lateral hamstring (LH) muscles. The strength of the knee flexor was measured with a load-cell-type strength-measurement sensor. Data were analyzed using one-way repeated analysis of variance. Results: The results showed that MH and LH activities and peak force were significantly different among the three tibial rotation conditions (p < 0.01). The post-hoc comparison revealed that the MH EMG activity in tibial neutral and internal rotation positions were significantly greater than tibial external rotation (p < 0.01). The LH activity in tibial external rotation was significantly greater than the tibial neutral position and internal rotation (p < 0.01). The peak force of the knee flexor was also greater in the external tibial rotation position compared with the tibial neutral and internal rotation positions (p < 0.01). Conclusion: Our findings suggest that hamstring muscle activation could be changed by tibial rotation.

• Radiation Oncology Journal
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• v.21 no.2
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• pp.174-181
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• 2003

Purpose: The target volume for the three field technique in breast cancer include the breast tangential and supraclavicular areas. The techniques rotating the gantry and couch angles, to match these two areas, will geometrically produce mismatching of the posterior edge between the medial and lateral tangential beams. This mismatch was confirmed by film dosimetry and three-dimensional computer planning. The correction methods of this mismatching were studied in this article. Materials and Methods: After the supraclavicular field was simulated using a half beam block and the medial and lateral tangential fields, by the rotation of the couch and gantry, we compared the following two methods to correct the mismatch. The first method was the rotation of coillmator until a line drawn on the posterior edge of tangential beams before the rotation of couch aligned the line drawn on the posterior edge after the rotation. The second method was the rotation of collimator according to the formula developed by the author as follows; Co=$2sin^{-1}${$sin\{theta}\{cdot}sin(C/2)$} (Co: collimator angle, $\theta$: angle between tangential beam and table, C: couch angle) Results: The film dosimetry showed the mismatching of posterior edges of the medial and lateral tangential fields prior to the rotation of collimator, while the posterior edges matched well after the rotation of collimator according to the formula. The three-dimensional computer plan also showed that the posterior edges matched well after the rotation of collimator accordingly. The DVH of the ipsilateral lung with the proper rotation of collimator angle was better than that without the rotation of collimator angle. Conclusion: The mismatching of the posterior edges of the medial and lateral tangential fields can be recognized on the three fileld technique in breast irradiation when the gantry and couch are simultaneously rotated and can be corrected with the proper rotation of the collimator angle. The radiation dose to the ipsilateral lung could be lowered with this technique.

• Journal of the Korean Society of Physical Medicine
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• v.12 no.1
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• pp.43-49
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• 2017

PURPOSE: This study investigated the relationship among hip adduction angle, tibial rotation, and ITB length during an Ober test to determine the most appropriate position for performing the test. METHODS: The study included thirty-nine asymptomatic participants (23 males, 16 females). Their hip adduction angles were measured using the Ober test during three tibial rotation conditions (internal tibial rotation, external rotation, and neutral position). ITB length was calculated by measuring the position of the patella to lateral femoral condyle using ultrasonography (patella-condyle distance; PCD). RESULTS: The relationship among hip adduction angle, tibial rotation, and ITB length was analyzed under the three conditions using the Pearson correlation. The hip adduction angle of the internal tibial rotation, the external rotation, and the neutral position were significantly related to ITB length. Moreover, the hip adduction angle measured during the internal tibial rotation had the highest correlation with ITB length among the three conditions (r=.58, p<.001). CONCLUSION: Internal tibial rotation caused by the Ober test led to increased iliotibial band (ITB) tension and a decreased adduction angle. These findings support that tibial rotation influences the flexibility of ITB. Therefore, therapists should consider the position of the internal tibial rotation when taking measurements using an Ober test.

• Journal of Korean Clinical Health Science
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• v.1 no.1
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• pp.29-34
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• 2013

Purpose : This study was to investigate that tongue positions have effect on the cervical range of motion (ROM). Methods : 18 subjects, 20 to 25 years of age, were participated in this study. The tongue positions were neutral position, anterior protrusion, posterior protrusion, superior protrusion, inferior protrusion, left side protrusion and right side protrusion. The neck movements were right side flexion, left side flexion, right rotation and left rotation. The cervical range of motion measured by cervical range of motion instrument (CROM, C9266-49, USA). The changes were analyzed using the paired t-test. SPSSWIN (ver. 20.0) was used for data analysis and the significance level was chosen as ${\alpha}$=0.05. Results : In the lateral flexion, the angle of left lateral flexion increased in anterior protrusion(p<0.05) and right side protrusion(p<0.05) significantly. In the rotation, the angle of right rotation increased in anterior protrusion(p<0.05), posterior protrusion (p<0.05), superior protrusion(p<0.05), inferior protrusion(p<0.05), and left side protrusion (p<0.05) significantly. Conclusions : In conclusion, we found that the tongue positions affected some cervical movements.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.6 no.1
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• pp.53-61
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• 2011

Objective: The purpose of this study is to evaluate the disc block subluxation for lumbar scoliosis and herniation of nucleus pulpous (HNP). Methods: We used AP & Lateral view X-ray for patients. And we measured of disc wedge angle, vertebral body rotation to evaluate the typical and atypical disc block subluxation. Results: On the analysis of the lateral view X-ray, 4th lumbar intervertebral disc angle (I.V.D angle) showed $4^{\circ}$, $5^{\circ}$, $3^{\circ}$, $0^{\circ}$ in the cases. On the 4th lumbar analysis of the AP view X-ray, lumbar scoliosis showed right disc wedge angle was $11^{\circ}$ (case 1), $17^{\circ}$ (case 2) and left vertebral body rotation was 13mm, 6mm. Lumbar HNP showed left disc wedge angle was $5^{\circ}$ (case 3), $4^{\circ}$ (case 4) and left vertebral body rotation was 2mm, 4mm. Conclusions: Disc block subluxation has been in lumbar scoliosis, but not been in lumbar HNP.

• Physical Therapy Korea
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• v.27 no.3
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• pp.178-184
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• 2020

Background: Stroke patients have reduced trunk control compared to normal people. The ability to control the trunk of a stroke patient is important for gait and balance. However, there is still a lack of research methods for the characteristics of stroke control in stroke patients. Objects: The aim of this research was to determine whether trunk position sense has any relation with balance and gait. Methods: This study assessed trunk performance by measuring position sense. Trunk position sense was assessed using the David back concept to determine trunk repositioning error in 20 stroke patients and 20 healthy subjects. Four trunk movements (flexion, extension, lateral flexion, rotation) were tested for repositioning error and the measurement was carried out 6 times per move; these parameters were used to compare the mean values obtained. Subjects with stroke were also evaluated with clinical measures of balance and gait. Results: There were significant differences in trunk repositioning error between the stroke group and the control group in flexion, lateral flexion to the affected side, lateral flexion to the unaffected side, rotation to the affected side, and rotation to the unaffected side. Mean flexion error: post-stroke: 7.95 ± 6.76 degrees, control: 3.32 ± 2.27; mean lateral flexion error to the affected side: 6.13 ± 3.79, to the unaffected side: 5.32 ± 3.15, control: 3.57 ± 1.92; mean rotation error to the affected side: 8.25 ± 3.09, to the unaffected side: 9.24 ± 3.94, control: 5.41 ± 1.82. There was an only significant negative correlation between the repositioning error of lateral flexion and the Berg balance scale score to the affected side (-0.483) and to the unaffected side (-0.497). A strong correlation between balance and gait was found. Conclusion: The results of this study indicate that stroke patients exhibit greater trunk repositioning error than age-matched controls on all planes of movement except for extension. And lateral flexion has correlation with balance and gait.