• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.469-474
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• 1999

The object of study is analysis to joint crack behavior of cracked joint concrete pavement. In the new constructing concrete pavement, joint crack behavior was compared general joint depth D/4 with joint depth D/3 and D/5 that it's environmental effects changed temperature and humidity. After joint saw cutting joint section was predicted crack at joint depth D/5 test section from the result for monitoring development of crack. In the setting of data logger system of the joint section, it's data compared see with the naked eye. In the research, development of crack at the joint section should effect to joint saw timing latter than joint depth. This performance could be the minimum of deterioration to the early curing. In this research, At new constructing of joint concrete pavement of highway, the monitoring system be setting after finished paving and joint sawing. The system and see with the naked eye could be analysis to pavement behaviors from collecting data at the test section. This system could be monitoring shot term and long term. In this report, joint section of crack behavior analysis used to collected data during a month after paving and joint sawing.

• 콘크리트학회논문집
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• 제23권3호
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• pp.289-294
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• 2011

콘크리트 슬래브의 수축으로 인해 발생하는 응력에 의한 무분별한 균열을 억제하기 위해 줄눈을 설치한다. 그러나 설치된 줄눈의 간격은 구체적인 산출 근거나 정량적인 기준 없이 경험적으로 나누어지고 있다. 따라서 이 연구에서는 콘크리트 슬래브의 수축 응력에 의한 변형량을 측정하고 이에 따른 정량적인 평가 기준을 제시하고자 한다. 노출된 환경 조건은 온도 $15^{\circ}C$, 상대습도 60%를 적용하였다. 건조수축 실험은 현재 슬래브 설계에 많이 사용되는 설계 강도 30 MPa 및 40 MPa 배합을 사용하였고 그 결과를 기존 건조수축 모델에 적용하였다. 그 결과 ACI 209R 모델에 가장 일치하는 것으로 나타났으며 이를 바탕으로 콘크리트 슬래브의 정량적인 줄눈 간격을 산정하였다.

• 한국전문물리치료학회지
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• 제22권3호
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• pp.12-22
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• 2015

The purpose of this study was to investigate the effect of taping on knee joint for patellofemoral compressive force (PCF) during stair descent for elderly women. Ten healthy elderly women voluntarily participated in this study. A three-dimensional motion analysis system 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 maximum PCF, maximum quadriceps contraction force and maximum knee extension moment (p>.05) but, there was a pattern decreasing all values with the taping during stair descent. There were significant differences for the knee and ankle angle on the event of maximum PCF (p<.05) and there was a pattern decreasing all values with the taping during stair descent. Therefore, taping on the knee would be effective to relieve the pain like patellofemoral pain syndrome in the knee joint.

• The Journal of Korean Physical Therapy
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• 제35권2호
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• pp.53-57
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• 2023

Purpose: The purpose of this study was to compare the changes in the muscle activation of the quadriceps muscle (rectus femoris, vastus lateralis, vastus medialis) during the stand-to-sit (StandTS) movement according to the plantar flexion angle of the ankle joint. Methods: A total of 22 healthy young females participated in this study. During the StandTS under the three conditions (plantarflexion angle 0°, 20°, and 45° of the ankle), electromyography (EMG) data (% maximum voluntary iso¬metric contraction) of the rectus femoris, vastus lateralis, and vastus medialis were recorded using a wireless surface EMG system. Results: There was a significant difference in the muscle activation of rectus femoris, vastus lateralis, and vastus medialis according to the plantar flexion angle (0°, 20°, and 45°) of the ankle. The muscle activation of the quadriceps was the highest at a 45° angle of plantarflexion and the lowest at 0°. One-way repeated ANOVA was used to analyze the muscle activation data of the lower extremity muscles according to the angle of the ankle joint. Conclusion: Based on the results of our study, it was confirmed that the muscle activity of the quadriceps can be increased even in the StandTS movement, which involves the eccentric contraction of the quadriceps muscle. This suggests that maintaining a plantar flexion posture for a long time, say by wearing high-heeled shoes, can quickly cause muscle fatigue in the lower-limb muscles, which can cause a decrease in balance ability leading to falls.

• 한국운동역학회지
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• 제21권3호
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• pp.335-343
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• 2011

Patellofemoral pain syndrome is the most common problem involving the knee, accounting for 25% of knee injuries. Repetitive, overuse activities cause increased force at the patellofemoral joint, resulting in pain during flexion and extension activities. Most research have been conducted in exploring the patellofemoral compressive force in gait, squat and lunges, even though in real cases, possibilities in landing exist. The purpose of this study was to compare the differences in patellofemoral compressive force according to two different height. Sixteen collegiate male students(age: 22.25 ${\pm}$ 3.30 yrs, height: 177.25 ${\pm}$ 4.44 cm, weight: 77.50 ${\pm}$ 8.18 kg) were chosen. The subjects performed drop landings in 45 cm, 60 cm. The findings demonstrated that higher height showed peak knee extension moment, quadriceps contraction force, patellofemoral compressive force with increased VGRF. Regarding the patellofemoral joint compressive force, it increased by quadriceps contraction force with knee flexion during landing, yet, it showed no difference in maximal knee flexion. To minimize patellofemoral joint stress and reduce the likelihood of developing PFPS, we recommend that predesigned quadriceps and hip muscle group strengthening are needed during conditioning and training.

• 한국전문물리치료학회지
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• 제23권1호
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• pp.20-30
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• 2016

Background: Total knee arthroplasty (TKA) recovers the alignment of the knee joint, but fails to automatically restore the alignment and function of the hip and ankle joints. It may affect the alignment and stability of the knee joint, therefore therapeutic intervention in hip and ankle joint is necessary for the rehabilitation process after TKA. Objects: The aim of this study was to comparison of the effects of the two exercise methods on the coronal plane alignment after TKA. This study conducted an experiment by dividing subjects into a lower extremity isometric co-contraction group (LEIC) and a quadriceps isolated isometric contraction (QIIC) group. Methods: A total of 37 subjects were randomly assigned to the LEIC ($n_1$=19) or the QIIC ($n_2$=18). Exercise was applied to five times per week for three weeks, starting on the eighth day after surgery. Range of motion exercises were performed as a common intervention and then each group performed quadriceps isometric contraction exercises with 10 sets of 5 repetitions. Radiological imaging was performed prior to surgery, one month and six months after surgery. In addition, the hip-knee-ankle angle (HKA) and tibiotalar angle (TTA) were measured. Results: The HKA was close to neutral in the LEIC rather than the QIIC (p<.05). The LEIC showed varus and the QIIC exhibited valgus TTA (p<.05). In a comparison of HKA and TTA over time, there was no significant change in either group (p>.05). According to the comparison of the TTA before surgery, the LEIC showed significant changes in the varus direction (p<.05), while there was no significant change in the QIIC (p>.05). Conclusion: The LEIC method triggered changes in the TTA and brought the HKA close to the neutral. Thus, LEIC is more effective than QIIC in creating stability in the coronal plane alignment of the knee and ankle joints after TKA.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.809-812
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• 1999

This research analyzed the factors for crack generation and proposed the recommended construction methods for the efficient crack control of underground RC box structures under the roadway. The selected main factors were: details of contraction joints, ratio of crack control rebars in longitudinla direction, and placement of flyash concrete. These factors were tested on the actual structures and the significance of each factor was analyzed, The results show that the flyash concrete placement and the inducting minor cracks in a certain direction by adopting contraction joints are practical and efficient methods to control cracks. The significance of crack generating factors increases as the sectional loss of contraction joint spacing increase. It was recommeded that the sectional loss should be higher than 20 percent to maximize the crack generating effects. It was not possible to verify the effect of crack control rebar spacing, but it was estimated that the ratio of crack control rebar should be increased to minimize cracks.

• The Journal of Korean Physical Therapy
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• 제13권2호
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• pp.399-405
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• 2001

Attainment of the goals of functional electrical stimulation(FES) applications such as strengthening of muscle, increasing muscular endurance, improvement in joint range of motion or the reduction of spasticity does not insure that patients will be able to produce voluntary muscle contraction sufficient to maintain posture or produce purposeful movements. In many patients who have sustained CNS damage, the control exerted by higher nervous system center over muscle contraction may impaired. In Searched patients, a variety of advanced therapeutic exercise techniques have been employed traditionally to facilitate the return of controlled functional muscular activity or maintain postural alignment until recovery from dysfunction occurs Among the most common clinical applications of FES for functional muscle contraction is as a substitute for static or dynamic orthotic devices

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제26권3호
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• pp.111-131
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• 2019

We introduce (CLRg) property for hybrid pair $F:X{\times}X{\rightarrow}2^X$ and $g:X{\rightarrow}X$. We also introduce joint common limit range (JCLR) property for two hybrid pairs $F,G:X{\times}X{\rightarrow}2^X$ and $f,g:X{\rightarrow}X$. We also establish some common coupled fixed point theorems for hybrid pair of mappings under generalized (${\psi},{\theta},{\varphi}$)-contraction on a noncomplete metric space, which is not partially ordered. It is to be noted that to find coupled coincidence point, we do not employ the condition of continuity of any mapping involved therein. As an application, we study the existence and uniqueness of the solution to an integral equation. We also give an example to demonstrate the degree of validity of our hypothesis. The results we obtain generalize, extend and improve several recent results in the existing literature.

• 대한물리의학회지
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• 제5권3호
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• pp.405-412
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• 2010

Purpose : The purpose of this study was to assess the effects of the trunk muscle activity on bridging exercise according to the knee joint angle. Methods : Twenty-five healthy adults volunteered to participate in this study. Subjects were required to complete following four bridging exercises; knee joint flexion $120^{\circ}$, $90^{\circ}$, $60^{\circ}$, $45^{\circ}$. Surface electromyography from selected trunk muscles was normalized to maximum voluntary isometric contraction. Muscle activity was measured by QEMG-4 system(LXM 3204, Laxtha Korea). A repeated measures of one-way ANOVA with post-hoc Bonferroni's correction was used to determine the influence of bridging exercise on muscle activity for each muscle and descriptive statistics was used to determine local/global muscle ratio. Results : The internal oblique of bridging exercises $120^{\circ}$, $90^{\circ}$ showed significantly(p<.05). The erctor spinae of all bridging exercises showed significant excepted between $60^{\circ}$ and $45^{\circ}$(p<.05). Median of internal oblique/rectus abdominis ratio of $120^{\circ}$ was 4.41, $90^{\circ}$ was 3.94, $60^{\circ}$ was 3.58, $45^{\circ}$ was 3.39. Median of internal oblique/external oblique ratio of $120^{\circ}$ was 2.66, $90^{\circ}$ was 2.43, $60^{\circ}$ was 2.87, $45^{\circ}$ was 2.64. Conclusion : Angular motion decreasing with knee joint flexion made erector spinae activation increase. on the other hand, as decreasing abdomen muscle activation, the more performing motor learning is required for abdomen muscle strength and co-contraction for the trunk stabilization.