• Earthquakes and Structures
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• 제20권1호
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• pp.29-38
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• 2021

According to ACI 224.3R-95 (ACI, 2013), construction joints (cold joint) in the column are to be provided at the top of floor slab for column continuing to the next floor and underside of floor slab and beam. A recent study reveals that providing cold joint of the mentioned location significantly reduced the seismic performance of the frame structures. Since, the construction joints in multi-story frame structures normally provided at the top of the floor slabs and at soffit of the beam in the column. This study investigated the effect of construction joint at various location in the column of beam-column joint such as at the top of floor slab, soffit level of the beam, half the depth of beam below the soffit of the beam and at a full depth of the beam below the soffit of the beam. The study revealed that there is an improvement in seismic capacity of the specimens as the location of cold joint is placed away from the soffit of the beam for lower story column.

• 디지털융복합연구
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• 제14권6호
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• pp.513-518
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• 2016

다양한 연구결과에도 불구하고 전신진동운동이 인체에 미치는 기전은 명확히 제시되고 있지 않으며, 진동이 하지관절의 운동역학적 변화에 대해 분석한 연구는 미비한 실정이다. 그러므로 이 연구는 어떠한 하지관절의 운동역학적 변인이 수직점프 능력에 영향을 미치는지 분석하고자 한다. 최근 6개월간 하지에 정형외과적 병력이 없는 건강한 성인 남성 5명과 여성 5명은 5분간 30Hz의 전신진동운동을 실시한 전 후로 스쿼트 점프를 각각 3회씩 실시하였고, 수직점프 시 하지관절의 운동역학적 변화를 분석하기 위하여 3D 영상분석 시스템을 활용하였다. 대상자들의 스쿼트 점프 높이는 전신진동운동 처치 이후 향상되는 것으로 나타났으며, 발목과 무릎관절에서 하지관절 모멘트와 파워가 증가하는 것으로 나타났다. 그러나 지면반력 값과 엉덩관절의 모멘트와 파워는 전신진동운동의 처치 전 후에 통계적으로 유의한 차이가 나지 않는 것으로 나타났다. 30Hz의 전신진동운동을 실시한 결과 발목과 무릎관절은 진동이 인체내 긍정적인 영향을 미치는 것으로 나타났으나 엉덩관절의 경우 부정적인 영향을 미치는 것으로 나타났다.

• Journal of Welding and Joining
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• 제20권3호
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• pp.122-128
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• 2002

The laser welding in the automotive industries has been used widely for the butt joint of blank sheets rather than the lap joint of automotive body panels. But as a substitute far the spot welding of automotive body panels, the so called three dimensional laser welding will be important far the body panel engineers. Specially the laser welding of body panels with a smooth weld line is applied increasingly, for example, to the side panels. So far, some criteria of the laser weld quality was suggested by in-house regulations or national standards from experiences and/or rule of thumbs. In the manufacturing places, a go or no-go criterion is adopted because of the simplicity or a lack of rational criteria. It is true specially for the selection of the process parameters, which gives the basic causes for the good quality of laser welds. In this study, the effects of joint combination, gap and welding speed on the lap joint $CO_2$ laser welding of two mild steel sheets with different thicknesses are obtained through a $2{\times}3{\times}7$ factorial experiment. The results of the weld quality are statistically analysed using analysis of variance (ANOVA) and compared between two characteristic zones, which are separated by the type of sectional shapes and the level of input energy per volume. The thickness combinations are 0.8mm/1.2mm, 1.2mm/0.8mm of mild steel sheets. The welding speed covers from the deep penetration to the partial penetration. The gap size has three levels of no-gap, 0.16m, and 0.26mm. The bead width, penetration depth and input energy per volume are measured and used as the weld quality criteria.

• Ocean Systems Engineering
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• 제13권1호
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• pp.43-55
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• 2023

In this study, the SCFs in tubular T-joints stiffened with external ring under axial load are studied and discussed. After verification of the present numerical model with the results of several available experimental tests, 156 FE models were generated and analyzed to parametrically evaluate the effect of the joint geometry and the ring geometry on the SCFs. Results indicated that the SCF of the stiffened T-joints at crown point can be down to 24% of the SCF of the corresponding un-reinforced joint at the same point. Also, the effect of the ring on the SCF at saddle point is more remarkable than the effect of the ring on the SCF at crown point. Moreover, against un-reinforced joints under axial load, the SCF at saddle point of the stiffened joint is smaller than the SCF at crown point of that stiffened joint. The ring results in the redistribution of stresses in the ring and metal substrate. Also, the effect of the ring thickness on the decrease of the SCFs is slight and can be ignored. In final step, the geometric parameters affecting the SCFs of the stiffened T-joints are analyzed by multiple nonlinear regression analyses. An accurate formula is proposed for determining the SCFs.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제48권1호
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• pp.33-40
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• 2022

Objectives: Prolotherapy is a method that has gained popularity in recent years and has been reported to have positive short-term and long-term clinical results in maxillofacial surgery, especially temporomandibular joint (TMJ) hypermobility. This study aimed to evaluate the changes in the trabecular structure of mandibular condyles in patients who underwent prolotherapy due to TMJ hypermobility using the fractal analysis method. Materials and Methods: Forty-five patients who received dextrose prolotherapy at a concentration of 20% and fifteen control patients were included in the study. All patients had panoramic radiographs just before (T0) and six months after treatment (T1). The patients who received treatment were divided into three groups according to the number of prolotherapy injections. The regions of interest were selected from bone areas close to the articular surfaces of the condyles. The fractal dimension (FD) values were calculated. Results: The main effect of time on the FD value was significant [F (1, 56)=86.176, P<0.001]. This effect was qualified by a significant time×group interaction effect [F (3, 56)=9.023, P<0.001]. The decreases in FD values in all treatment groups between T0 and T1 times were significant (P=0.004). However, changes in FD values were not significant in the control group (P=0.728). Conclusion: Dextrose prolotherapy without the effect of the number of injections caused a decrease in FD values in the mandibular condyles over time.

• 한국전문물리치료학회지
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• 제18권2호
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• pp.1-8
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• 2011

The purpose of this study was to investigate the effect of high heeled shoes with the total contact insert (TCI) on the frontal plane of the joints for the lower extremity during the gait. Ten healthy females voluntarily participated in this study and the height of the high heeled shoes was 7 cm. A three-dimensional motion analysis system (VICON) and force plates were used to analyze the movements of the joints for the lower extremities. The results were as follows: There were no significant differences for the angle value on the event of the gait cycle in the maximum eversion and inversion of the ankle joint, the varus and valgus of the knee joint, and the adduction and abduction of the hip joint (p>.05). But, there was a significant difference or the range of motion in the ankle joint (p<.05). The value of ankle and knee moment with a TCI was less than the value for no TCI. And there were significant differences for the moment value of the maximum inversion and eversion on the ankle joint and for the maximum varus and valgus on the knee joint (p<.05). Therefore, a TCI would be effective in stabilizing the joints of the lower extremities and increasing the balance of a body to reduce the injure from a fall during the gait.

• 대한한의진단학회지
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• 제19권2호
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• pp.125-132
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• 2015

Objective This study investigated the effect of Korean Traditional medicine treatment with Acupuncture, Cupping, Physical Therapy and Ganghwalijetong-yeum(Qianghuochutong-yin) on Knee joint Osteoarthritis patients. Methods 5 Knee joint Osteoarthritis patients were treated with Ganghwalijetong-yeum(Qianghuochutong-yin), acupunture, cupping, physical therapy and exercise for Knee joint Osteoarthritis. K-WOMAC(Western Ontario and McMasters Universitis) Index, VAS(Visual Analogue Scale) were checked to evaluate the effectiveness of the treatment. Results K-WOMAC of patients treated with Ganghwalijetong-yeum(Qianghuochutong-yin) is improved from $67.00{\pm}24.41$ to $44.80{\pm}21.18$ and there was statistical significance(p<0.05). VAS of patients treated with Ganghwalijetong-yeum(Qianghuochutong-yin) is also improved from $4.20{\pm}1.79$ to $2.30{\pm}1.10$ but there was no statistical significance(p>0.05). Conclusions According to the study, Korean Traditional complex therapy with Ganghwalijetong-yeum(Qianghuochutong-yin) might improve Knee joint Osteoarthritis.

• 국제물리치료학회지
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• 제3권1호
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• pp.406-411
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• 2012

This study aims to examine the effect of patellar taping common to patients with patellofemoral pain syndrome on the change of knee joint location. The total number of participants is 12 patients with no pain in their knee. There are three different experiments: no-taping, placebo taping, and patellar taping. After application, they squat on their hams. As a result, both the muscle activity of vastus medialis and that of vastus lateralis increased in placebo taping compared to no-taping, which wasn't statistically significant. However, the muscle activity of vastus medialis and that of vastus lateralis decreased in patellar taping compared to no-taping, which was statistically significant. This suggests that patellar taping causing the lateral attraction of knee joint is more influential to the dynamics of knee joint than skin afferent input in placebo taping. Therefore, patellar taping is effective to change the location of knee joint, affect the muscle activity of quadriceps muscle of thigh, and thus correct the misalignments of the knee joint.

• 국제물리치료학회지
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• 제9권1호
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• pp.1381-1386
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• 2018

The purpose of this study is to investigate the effect of pelvic, Lumbar spine and Cervical spine manipulation on the joint position sense in normal adults. Thirty normal adults were divided into an experimental group of 15 subjects and a control group of 15 subjects. The experimental group was treated with pelvic, Lumbar spine and Cervical spine manipulation with massage, whereas the control group received only massage. Both groups were evaluated in terms of joint position errors (JPEs) using a digital dual clinometer before and after the experiment. The comparison of the JPEs of the experimental group and the control group before and after the experiment showed that the experimental group's cervical spine results were significantly different in the flexion, left lateral flexion, and right rotation (p < .05) and lumbar spine results were significantly different in the flexion and extension (p < .05), but the control group's results were not statistically significant in all items (p > .05). The pelvic, lumbar spine and cervical spine manipulation makes an effect on the joint position sense in normal adults. The findings of this study suggest that the pelvis, lumbar spine and cervical spine manipulation improve the motor ability in people with low joint position sense.

• Structural Engineering and Mechanics
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• 제59권2호
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• pp.313-326
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• 2016

In this study the three-dimensional nonlinear finite element method was used to analyze the stresses distribution in the adhesive layer used to joint two Aluminum 2024-T3 adherends. We consider in this study the effect of different parameters witch directly affect the values of different stresses. The experimental design method is used to investigate the effects of geometrical parameters of the single lap joint in order to achieve an optimization of the assembly with simple lap joint. As a result, it can be said that both the geometrical modifications of the adhesive and adherends edge have presented a significant effect at the overlap edge thereby causing a decrease in peel and shear stresses. In addition, an analytical model is also given to predict in a simple but effective way the joint strength and its dependence on the geometrical parameters. This approach can help the designers to improve the quality and the durability of the structural adhesive joints.