• KCI Concrete Journal
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• 제12권1호
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• pp.113-120
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• 2000

This paper presents the behavior and strengthening effect of reinforced concrete rectangular beams strengthened using CFRP sheets with different strengthening level. In general, normally strengthened beams are failed by interfacial shear failure (delamination) within concrete, instead of by tensile failure of the CFRP sheets. The delamination occurred suddenly and the concrete cover cracked vertically by flexure was spalled off due to the release energy. The strengthened beams were stiffer than the control beam before and after reinforcement yielding. The ultimate load considerably increased with an increase of strengthening level, while the ultimate deflection significantly decreased. The tensile force of CFRP sheets and average shear stress of concrete at delamination failure were curvilinearly proportional to the strengthening level. Therefore, the increment of ultimate load obtained by strengthening was curvilinearly proportional to the strengthening level. The averaged horizontal shear stress of concrete at the interface ranges between (equation omitted) and (equation omitted) (in kg/$\textrm{cm}^2$) depending on strengthening level.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.781-786
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• 2000

This paper presents the behavior and strenghening effect of reinforced concrete rectangular beams strengthened sing CFRP sheets with different strengthening level. In general, normally strengthened beams are failed by interfacial shear failure (delamination) within concrete, instead of by tensile failure of the CFRP sheets. The delamination occurred suddenly and the concrete cover cracked vertically by flexure was spalled off due to the release energy. The ultimate load considerably increased with an increase of strengthening level, while the ultimate deflection significantly decreased. The tensile force of CFRP sheets and average shear stress of concrete at delamination failure were curvilinearly proportional to the strengthening level. Therefore, the increment of ultimate load obtained by strengthening was curvilinearly proportional to th strengthening level.

• 콘크리트학회논문집
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• 제16권5호
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• pp.667-675
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• 2004

본 논문은 CFRP 격자 보강재로 보강한 콘크리트 슬래브의 파괴형태와 보강설계기준에 대한 연구이다. 실험 연구에서 채택한 시험변수로는 CFRP 격자 보강재의 양, 보강 모르타르의 깊이, 앵커핀의 유무, 압축부 보강 등이다. 연구에 의하면 CFRP 격자 섬유 보강량에 따라 파괴형태가 다르게 나타났는데 낮은 보강수준에서는 FRP 격자의 인장 파단파괴를 보였고 보통의 보강정도에서는 격자층 계면전단파괴가 발생하였다. 높은 보강량을 가진 슬래브에서는 사인장전단파괴 형태를 나타냈다. 보강 효과는 FRP 격자 보강재의 양이 증가할수록 증대하였으나 취성 전단파괴에 의해 연성은 감소되었다. 따라서 FRP 격자 보강량을 제한함으로써 갑자기 하중 지지력을 상실하는 전단파괴를 피할 수 있다. 파괴형태 중 CFRP 파단파괴가 바람직한데 그 이유는 섬유파단 후에도 극한상태에서 보강 전 슬래브의 하중지지력과 연성을 가지고 있기 때문이다. 마지막으로 본 논문은 CFRP 격자섬유보강설계기준과 과정을 제시하고 있다.

• 대한물리의학회지
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• 제2권1호
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• pp.31-39
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• 2007

Purpose : The main purpose of this study was to investigate the influence of lower extremity strengthening on balance ability of knee osteoarthritis. Methods : The walking exercise group with modality treatment and strengthening exercise group with modality treatment. The walking exercise and strengthening for 40 minutes per day and three times a week during 6 weeks period. Short Form McGill Pain Questionnaire(SFMPQ) was used to measure patient's pain level. Patient Specific Functional Scale(PSFS) was used to measure patient's functional disability level. BPM was used to measure sway area. Global Perceived Effect Scale(GPES) was used to measure recovery or worse of patient's condition. Results : 1. SFMPQ was strengthening exercise group showed significantly decreased more than walking exercise group(p<.05). 2. PSFS was strengthening exercise group showed significantly increased more than walking exercise group(p<.05). 3. Sway area was strengthening exercise group showed significantly limited area more than walking exercise group(p<.05). 4. GPES was strengthening exercise group showed significantly increased more than walking exercise group(p<.05). Conclusion : This study will be used as exercise method of patient with osteoarhtritis.

• PNF and Movement
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• 제19권1호
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• pp.57-65
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• 2021

Purpose: This study investigated the effects of proprioceptive neuromuscular facilitation (PNF) respiratory muscle strengthening exercise on the pulmonary function, back pain, and disability level of patients with chronic low back pain (CLBP). Methods: There were 24 CLBP patients randomly divided into the experimental group (n = 12) who took part in PNF respiratory muscle strengthening exercise and the control group (n = 12) who performed a mock treatment. Both groups performed their respective interventions for 15 min five times per week for four weeks. The pulmonary function was measured using a portable spirometer. The back pain of the participants was assessed using a visual analogue scale. The Oswestry disability index was conducted to measure disability level. A paired t-test was performed to compare within-group changes before and after the PNF respiratory muscle strengthening exercise. Differences between the experimental and the control groups were analyzed using an independent t-test. For all tests, the level of statistical significance was α = 0.05. Results: The within-group change in pulmonary function was significantly different in the experimental group (p < 0.05), and the levels of back pain and disability were significantly different between the groups (p < 0.05). There was also a significant between-group difference in pulmonary function, back pain, and disability level after intervention (p < 0.05). Conclusion: These results suggest that PNF respiratory muscle strengthening exercise enhances pulmonary function and reduces levels of back pain and disability in patients with CLBP.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.251-254
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• 2005

This study will have to define the shear strengthening effects of steel fiber in beam and column levels, as well as to suggest estimation method of maximum shear capacity of structural members. From review of literature surveys and perform structural member test results, following conclusion can be made; In beam level, steel fiber strengthening factor is suggested from the tensile splitting test results and beam test results. After suggesting shear capacity of beam without stirrups and beam with stirrups by proposed steel fiber strengthening factor, proposed equation is possible to evaluate the shear capacity of beam. In column level, with column test results and proposed steel fiber strengthening factor, shear capacity equation of steel fiber reinforced concrete in column is suggested.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.13-14
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• 2012

This study investigates the effect of adhesive type applying to surface-strengthening Ondol floor on level of attachment. Adhesive materials of four types produced in different companies were prepared and their attaching performance was examined. Test results showed that the water-based epoxy type produced in S company was the most effective on attaching the pieces of the surface-strengthening Ondol floor product.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.546-550
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• 1993

Three basic experiments in agricultural machinery management , strengthening the construction of socialized service system, facilitating the two-level management system in rural areas and carrying through the principle of " paid service ' are described and the main methods of strengthening agricultural machinery management are developed in this paper.aper.

• 대한물리의학회지
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• 제1권1호
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• pp.13-21
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• 2006

Purpose : The main purpose of this study was to investigate the influence of muscle strengthening exercise on balance ability of knee osteoarthritis. The subject were consisted of 30 women patients with knee osteoarthritis. Method : The strengthening exercise group with modality treatment. The strengthening exercise for 40 minutes per day and three times a week during 6 weeks period. Short Form McGill Pain Questionnaire(SFMPQ) was used to measure patient's pain level. Patient Specific Functional Scale(PSFS) was used to measure patient's functional disability level. BPM was used to measure sway area. Global Perceived Effect Scale(GPES) was used to measure recovery or worse of patient's condition. Results : 1. SFMPQ was muscle strengthening exercise showed significantly decreased more than before treatment(p<.05). 2. PSFS was muscle strengthening exercise showed significantly increased more than before treatment (p<.05). 3. Sway area was muscle strengthening exercise showed significantly limited area more than before treatment(p<.05). 4. GPES was muscle strengthening exercise showed significantly increased more than before treatment(p<.05). Conclusion : This study will be used as exercise method of patient with osteoarhtritis.

• 한국전문물리치료학회지
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• 제27권1호
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• pp.19-29
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• 2020

Background: Stretch-oriented home exercise programs are often used as treatments for patients with adhesive capsulitis; however, there is lack of research on home exercise programs to strengthen rotator cuffs. Objects: The aim of this study is to investigate the effect of home exercise programs for rotator cuff strengthening on pain, range of motion (ROM), disability level, and quality of life in patients with adhesive capsulitis. Methods: Twenty-two patients with adhesive capsulitis volunteered to participate in this study. The subjects were randomly divided into an experimental group (n = 11) and control group (n = 11). For the experimental group, manual therapy and home exercise programs for rotator cuff strengthening were applied for 6 weeks; for the control group, only manual therapy was applied for 6 weeks. Shoulder pain (quadruple visual analogue scale, QVAS), ROM, disability (shoulder pain and disability index-Korean version, SPADI), and quality of life (world health organization quality of life scale-Korean version, WHOQOL-BREF) were evaluated at baseline, after 3 weeks, and after 6 weeks of intervention. The changes in the measurement variables were analyzed by using repeated measure analysis of variance. Results: Significant differences were observed between the experimental group and control group in the QVAS; SPADI-pain scores; SPADI-disability scores; SPADI-total scores; flexion, abduction, internal and external rotation ROM of the glenohumeral joint; and WHOQOL-BREF total, overall, physical health, and psychological scores. All groups displayed statistically significant improvements as observed in the QVAS, SPADI, flexion, abduction, external and internal rotation ROM of the glenohumeral joint, and WHOQOL-BREF. Conclusion: Home exercise programs for rotator cuff strengthening had a positive impact on shoulder pain, shoulder ROM, disability level, and quality of life in patients with adhesive capsulitis. Therefore, we propose the use of home exercise programs for rotator cuff strengthening in the exercise rehabilitation of patients with adhesive capsulitis.