• 폴리머
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• 제36권3호
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• pp.372-379
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• 2012

본 연구에서는 실리카 나노입자의 표면을 실란 커플링제인 bis[3-(trimethoxysilyl)propyl]amine(BTMA)을 사용하여 개질하였다. BTMA의 가수분해 시간, 농도 및 개질 시간의 변화가 실리카 표면 개질 반응에 미치는 영향을 Fourier transform infrared spectroscopy(FTIR), elemental analysis(EA) 및 고체 상태 cross-polarization magic angle spinning(CP/MAS) nuclear magnetic resonance spectroscopy(NMR)법을 사용하여 분석을 수행하였다. 연구결과 BTMA의 가수분해 시간, 농도 및 표면 개질 시간이 증가할수록 3737 $cm^{-1}$에 나타나는 실리카의 고립 실란올(isolated silanol) 피크의 세기는 점점 약해지고, 도입되는 BTMA의 $-CH_2$ 기에 의한 신축(stretching) 및 굽힘(bending) 진동 피크는 점점 강하게 나타났다. EA 분석을 통한 N 및 C의 함량에서도 같은 경향을 나타내었다. BTMA를 사용한 실리카 입자의 처리 조건 중, BTMA의 농도 변화는 실리카 입자 표면과 반응하는 BTMA의 양에 큰 영향을 미치지만, BTMA의 가수분해 시간 및 표면 개질 반응 시간의 영향은 크지 않은 것으로 나타났다.

• 대한통합의학회지
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• 제3권4호
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• pp.61-67
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• 2015

Purpose : The purpose of this study was to find out the effect of exercise on the angle and distance between scapular stability and McKenzie stretch exercise. Method : 30 volunteers took part in this experiment and we divided into three groups(experimental group A, experimental group B, control group C). Experimental group A performed scapular stabilization exercise and experimental group B performed McKenzie neck stretching exercise and control group didn't perform any exercise. Experimental group(A, B) received a total of 12 exercise session over a 4 week period (three times per week). Posture and craniovertebral angle changes of the neck using GPS measurements reported. Result : The CVA and distance change after exercise were significantly reduced in the experimental group A and B. Conclusion : Therefore, we have confirmed through experiments reducing a CVA and distance between scapular stabilization and McKenzie neck stretching exercises, whereby we would also be helpful to ensure the treatment of forward head posture.

• 대한물리치료과학회지
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• 제11권3호
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• pp.38-48
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• 2004

The purpose of present study is to examine the relative efficacy of active exercise programs for work-related chronic low back pain and to figure out how much they affect mechanical stability of lumbar. Subjects are 43 employees with work-related chronic low hack pain, and they were randomly divided into two groups with general physiotherapy groups and thoracic exercise groups for increasing thoracic mobility. Active exercise programs were done 3 times a week, for 6 months, and the subjects were tested for Pain intensity(VAS), the Oswestry Disability Index, Maximal stretching with both hands in the overhead direction and the lumbar region angle of inclination. All subjects were reassessed with same measurement with Pre-study and 6 months after study After applying active exercise programs, pain intensity didn't show any significant difference between two groups. The Oswestry Disability Index showed significant difference between two groups and thoracic exercise groups decreased significantly compare to general physiotherapy group(p<0.05). Maximal stretching with both hands in the overhead direction showed significant difference between two groups and thoracic exercise group increased significantly more than general physiotherapy groups(p<0.05). The lumbar region angle of inclination showed significant difference between two groups and thoracic exercise group decreased significantly more than general physiotherapy groups (p<0.05). According to the results above, exercise for increasing thoracic mobility has an effect on lumbar stability. For the work-related chronic lower hack pain workers, it is far more effective for lumbar stabilization than general physiotherapy.

• 대한물리치료과학회지
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• 제16권1호
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• pp.11-20
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• 2009

Background: The purpose of this study was to investigate the effect of stretching and strengthening exercise on the static flexibility and pain intensity for the iliopsoas muscle, which is one of the main reasons for the chronic low back pain. Methods: The subjects of this study were 15 male adult patients with showed 6 score or higher in the visual analogue scale(VAS) and complained of low back pain over three months who visited department of the physical therapy, KIA motors Industrial Health Center, from October, 2008 through December, 2008. Fifteen subjects were trained stretching, mat exercises and sling exercises for iliopsoas muscle at 4-5 times a week for 4 weeks. I measured the changes on the extensibility of iliopsoas muscle, static flexibility of low back and VAS between pre- and post exercise treatment. Date were analyzed using the Wilcoxon's signed rank test considering the size of the samples. Results: 1. The angle of the hip joint that showed the extensibility of iliopsoas muscle was relieved, which was significant statistically (p<.05). 2. The static flexibility was statistically significantly improved in the trunk flexion test, trunk extension test and Schober-Test (p<.05). 3. The VAS showed decrease, which is significant statistically (p<.05). Conclusion: It is believed that the exercise treatment of iliopsoas muscle has the significant effects on the improvement of static flexibility and decrease of pain intensity for the chronic low back pain patients.

• Physical Therapy Rehabilitation Science
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• 제9권3호
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• pp.140-148
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• 2020

Objective: The purpose of this study was to examine the effectiveness of pelvic displacement when self-hamstring muscle stretches were applied to persons with low back pain. Design: Three-group pretest-posttest design. Methods: Forty persons with low back pain participated in this study. Pelvic tilt angle, hamstring flexibility, Quadruple Visual Analogue Scale (QVAS), Fear Avoidance Beliefs Questionnaire (FABQ), Korea version of the Oswestry Disability Index (KODI) and pelvic mobility were measured at pre-post. All participants were divided into either the pevic anterior tilt group (PAT group, n=12), pelvic midrange group (PMR group, n=18), or the pelvic posterior tilt group (PPT group, n=10). Self-stretching was performed using the pilates ring three times a week for a total of four weeks and the post-test was conducted and compared with the pre-test. Results: Hamstring flexibility, QVAS, KODI scores were significantly different compared to before the intervention (p<0.05). The changes in hamstring flexibility of the three groups were significantly different (p<0.05). Changes in KODI and FABQ results of the three groups were not significant. The pelvic posterior tilt range were significantly different in the PMR and PPT groups (p<0.05). The pelvic anterior tilt ranges showed significant differences after stretching in the PPT group (p<0.05). Conclusions: A large amount of change of hamstring flexibility, pelvic mobility of anterior and posterior tilt test in the PPT group was observed. Furthermore, therapists should consider pelvic displacement of the participant when applying intervention, which may, accordingly, have different effectiveness.

• Steel and Composite Structures
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• 제34권2호
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• pp.279-288
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• 2020

The computational post-buckling strength of the tilted sandwich composite shell structure is evaluated in this article. The computational responses are obtained using a mathematical model derived using the higher-order type of polynomial kinematic in association with the through-thickness stretching effect. Also, the sandwich deformation behaviour of the flexible soft-core sandwich structural model is expressed mathematically with the help of a generic nonlinear strain theory i.e. Green-Lagrange type strain-displacement relations. Subsequently, the model includes all of the nonlinear strain terms to account the actual deformation and discretized via displacement type of finite element. Further, the computer code is prepared (MATLAB environment) using the derived higher-order formulation in association with the direct iterative technique for the computation of temperature carrying capacity of the soft-core sandwich within the post-buckled regime. Further, the nonlinear finite element model has been tested to show its accuracy by solving a few numerical experimentations as same as the published example including the consistency behaviour. Lastly, the derived model is utilized to find the temperature load-carrying capacity under the influences of variable factors affecting the soft-core type sandwich structural design in the small (finite) strain and large deformation regime including the effect of tilt angle.

• 대한물리치료과학회지
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• 제26권3호
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• pp.57-69
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• 2019

Background: The purpose of this study was to compare and analyze the effects of neck and trunk combined exercise program and single exercise on neck angle and neck and shoulder muscle activity. Design: Randomized controlled trial. Methods: In the single exercise group, the basic stretching, head bending and neck bending exercises were performed. The neck and trunk combined exercise group performed torso strength and trunk stability exercises to stabilize the trunk, and then performed the same neck exercise as the single exercise group. The exercise program was conducted 5 days per week for 2 weeks. One-way repeated ANOVA was used to investigate the statistical analysis of neck angle, neck and upper and middle trapezius muscle activity. Results: 1) There was no significant difference in neck angle degree after exercise in neck single exercise group. 2) In the neck and trunk combined exercise, the neck angle degree decreased continuously with the increase of the experimental period and showed a significant difference. 3) In the single exercise group, the muscles which showed significant difference compared to the post-exercise were the right upper, left and right middle trapezius. 4) In the neck and trunk combined exercise group, the right neck muscles showed significant difference after the exercise before the experiment. Conclusion: It was found that the neck and trunk combined exercise was more effective in reducing neck angle and the muscle activity of the subjects with forward head posture was decreased and increased. However, both exercises showed positive effects.

• 한국방사선학회논문지
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• 제8권7호
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• pp.397-400
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• 2014

본 연구의 목적은 필라테스 운동이 척추 측만증 환자의 요추 Cobb's angle에 어떠한 영향을 미치는지의 효과를 알아보는데 있다. 이 운동의 효과를 검증하기 위하여 필라테스 자세교정운동(PCE), 척추스트레칭운동(SSE), 근육강화운동(MSE)등을 시행하였다. 자세교정운동은 불균형한 근육에너지를 바로잡아주며 척추스트레칭 운동은 척추주변의 과 긴장된 근육을 이완시키고 근육강화운동은 주동근과 길항근의 균형을 잡아주어 척추 주변 근육의 탄력성과 유연성을 회복시켜주게 된다. 연구방법은 필라테스 적용 전과 적용 후의 X-ray 촬영에 의한 요추의 Cobb's angle을 측정하여 검증하였다. X-ray 촬영을 통한 Cobb's angle 실험 전 후의 결과는 필라테스 실시 후 약 5도 정도에서 통계적으로 유의하게 감소하였다(p=0.005). 따라서 필라테스 운동이 척추 측만증에 완화에 도움이 되는 것으로 나타났다.

• 한국전문물리치료학회지
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• 제25권3호
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• pp.12-18
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• 2018

Background: Passive straight leg raising (PSLR) is the common clinical test to measure of hamstring muscle length. Hip flexion angle contributes to change the lumbopelvic rotation during PSLR. Pressure biofeedback unit (PBU) is commonly used to detect lumbopelvic movement during lower limb movements. Thus, there may be the relationship between pressure of PBU and lumbopelvic motion during PSLR. Objects: The objective of this study was to determine the relationship between pressure of PBU and lumbopelvic motion during PSLR. Methods: Thirty two subjects participated in this study. A three-dimensional motion analysis system were used to measure the lumbopelvic angle during PSLR, while recording the pressure of PBU according to angle of PSLR by 10 degree increments. Pearson product moment correlations and linear regression analysis were used to describe the relationship between variables. Results: The results showed that there was a significant relationship between the lumbopelvic and angle of PSLR (Pearson's r=.83, p<.05), between the pressure of PBU and angle of PSLR (Pearson's r=.75, p<.05), and between lumbopelvic motion and pressure of PUB (Pearson's r=.83, p<.05). Linear regression equation using lumbopevic angle as an independent factor was as follows: Pressure of PBU = 47.35 + (2.55 ${\times}$ angle of lumbopelvic motion) ($R^2=.69$, p<.05). Conclusion: Results of the present study indicate that pressure of PBU can be used to indirectly detect the amounts of lumbobevic motion during muscle length test or stretching of hamstring.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.285-287
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• 2014

Equations of motion for the vibration analysis of rotating pre-twisted beams with functionally graded material properties are derived in this paper. Based on Timoshenko beam theory, the effects of shear and rotary inertia are considered. The pre-twisted beam has a rectangular cross-section and is mounted on a rotating rigid hub with a setting angle. Functionally graded material (FGM) properties are considered along the height direction of the beam. The equations of stretching and bending motion are derived by Kane's method employing hybrid deformation variables. To validate the derived equations, natural frequencies of a rotating FGM pre-twisted beam are compared to those obtained by a commercial software ANSYS. The effects of the pre-twisted angle, slenderness ratio, hub radius, volume fraction exponent, and angular speed on the modal characteristics of the system are investigated with the proposed model.