• 한국전문물리치료학회지
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• 제23권3호
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• pp.57-67
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• 2016

Background: Many previous studies recommended the side-lying hip abduction (SHA) exercise for targeting the gluteus medius (Gmed) and gluteus maximus (Gmax) muscle activity while the decreasing tensor fasciae latae (TFL) activation. Mischoice of hip position and angle in SHA may increase the risk of lower extremity injuries and undesirable muscle activation. However, information is limited on the effect of composite hip flexion angles and hip rotation on the gluteal muscle activity during SHA. Objects: This study aimed to compare muscle activity (Gmed, TFL, and Gmax) and activity ratios (Gmed/TFL, Gmax/TFL, and Gmed/Gmax) using surface electromyography (EMG) during SHA exercise at three different hip flexion angles either with or without internal rotation (IR) in subjects with Gmed weakness. We hypothesized that applying hip flexion and IR during SHA would increase gluteal muscle activity and decrease TFL activity. Methods: Muscle activity and activity ratios in 20 volunteers with Gmed weakness during 6 different SHA were investigated with surface EMG. One-way repeated-measures analysis of variance was used to determine the statistical significance. Results: Significant differences were found among the six different exercises for Gmed ($F_{2,41}=11.817$, p<.001) and Gmax ($F_{3,52}=5.513$, p=.003) muscle activity, and Gmed/TFL ($F_{3,54}=8.735$, p<.001) and Gmax/TFL ($F_{2,37}=4.019$, p=.028) activity ratios. Conclusion: Applying hip flexion is an effective method for increasing gluteal activity, and it elicits great Gmed/TFL and Gmax/TFL activity ratios during SHA in subjects with Gmed weakness.

• Advances in concrete construction
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• 제8권4호
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• pp.277-283
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• 2019

In evaluating explosion-protection capacity, safety distance is broadly accepted as the distance at which detonation of a given explosive causes acceptable structural damage. Safety distance can be calculated based on structural response under blast loading and damage criteria. For the applicability of the safety distance, the minimum required stand-off distance should be given when the explosive size is assumed. However, because of the nature of structures, structural details and material characteristics differ, which requires sensitivity analysis of the safety distance. This study examines the safety-distance sensitivity from structural and material property variations. For the safety-distance calculation, a blast analysis module based on the Kingery and Bulmash formula, a structural response module based on a Single Degree of Freedom model, and damage criteria based on a support rotation angle were prepared. Sensitivity analysis was conducted for the Reinforced Concrete one-way slab with different thicknesses, reinforcement ratios, reinforcement yield strengths, and concrete compressive strengths. It was shown that slab thickness has the most significant influence on both inertial force and flexure resistance, but the compressive strength of the concrete is not relevant.

• 가정과삶의질연구
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• 제15권2호
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• pp.71-71
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• 1997

This study aims ai the extraction of what is universally to be taught in modern Korean Families and its scalization. That is, it attempts to provide the criterion by which we can determine what to teach adolescent in the family, not in society or school. For this purpose, this study firstly reviews the preceeding studies on the subject. As a result of the review, we postulate the hypothetical structure consisting of 11 domains. Secondary, we gather the parent's view on the topic by interviewing 496 parents with teenagers. On the basis of this study, we can construct the questionnaire(Likert scale; 5 point). After we conduct an extensive empirical research(346 parents) in order to generalize 195 items of the workedout questionnaire. We apply factor analysis(principal axis factoring, oblique (promax) rotation) in the verification of the validity. As the consequence, we select 66 items consisting, 10 factors, which explain 68% of common variance. We name the 10 educational factors extracted in the scale as follows ; The Sense of Value, Communal Society, Sex, Esteem for an ancestor & a traditional way of life, Parent-Child Relationship, the Culture life within the family, The Guide of Learning Way, Setting up the way of life, The control of one's life, Friendship. The reliability of the scale is the cronbach =0.91 which turns out to be satisfactory.

• 한국운동역학회지
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• 제19권3호
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• pp.435-448
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• 2009

본 연구는 노인의 계단과 경사로 오르기와 평지보행 동안 하지의 운동학적 변화를 분석하는 것이었다. 건강한 노인 14명(남:10, 녀:4)이 실험에 참여하였으며 측정도구는 삼차원동작분석기인 Vicon system(Vicon, Oxford Metrics, England)을 사용하였다. 보행주기 각 시점에서 하지 관절의 각도 변화를 보행 조건(평지, 계단, 경사로)에 따라 알아보기 위해 일요인 반복측정 분산분석(one-way repeated measure of ANOVA)을 사용하였다. 전후면상에서 골반은 평지 보행에서 보행 주기 동안 전방굴곡이 나타났으며 계단과 경사로 오르기에서 전방굴곡이 증가하였다. 고관절과 슬관절는 모두 평지보행과 비교해 계단 오르기에서 굴곡이 더 증가하였다. 족관절은 평지보행과 비교해 경사로 오르기에서 굴곡이 더 증가하였다. 좌우면상에서 보행 주기 동안 평지보행과 비교해 계단 오르기에서 골반이 크게 올라갔으며 고관절도 계단 오르기에서 내전과 외전의 변화가 크게 나타났다. 또한 슬관절도 계단 오르기에서 내반이 증가하였고 족관절 역시 계단 오르기에서 내번이 증가하였다. 수평면상에서 보행 주기 동안 골반은 평지 보행과 비교해 계단과 경사로 오르기에서는 내회전이 대체로 증가하였고 고관절은 계단과 경사로 오르기에서 내회전이 증가하였으나 통계적으로 유의한 차이는 없었다. 슬관절은 계단 오르기에서 대체적으로 내회전이 증가하였고 족관절은 계단 오르기에서 대체적으로 외회전이 증가하였다. 이러한 결과는 노인의 계단과 경사로 오르기는 평지 보행과 비교해 하지의 운동학적 보행 변수들을 크게 변화시키는 것을 알 수 있었다.

• 한국기계가공학회지
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• 제13권1호
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• pp.107-114
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• 2014

A friction hinge system which moves without power was designed and developed using the principle of friction force, which is caused by interference between the inner diameter of a silicon cap and the outer diameter of a cylindrical roller bearing with one-way rotation in a counterclockwise direction. The system was applied to the lid of buffet ware, which moved up by external force and moved down by gravitational force. However, design conditions which included a rotation angle of the hinge of more than 80 degrees and a closing time of more than 20 seconds were required when the lid of the buffet ware closed due to gravitational force. The design safety of the friction hinge body connected to the lid of the buffet ware from the hinge system was checked on the basis of structural, fatigue and thermal analyses. The material of the shaft, cap and flange among the hinge elements was changed to polyethylene from steel to reduce the weight of the friction hinge system. An injection molding simulation was performed and injection molds of the shaft, cap and flange were created. The weight of the hinge system was decreased from 805g to 219g.

• 자동차안전학회지
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• 제9권3호
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• pp.13-18
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• 2017

Since 2015, Euro-NCAP and C-NCAP have enhanced regulation on submarine of rear female passenger. This submarine regulation is a big obstacle to achieve the highest level crash performance. So the objective of this study is to develop new technical way to protect rear female passenger against submarine. In this study, we figured out how design factors of seatbelt affect submarine of rear female passenger by sled test. And we verified that rear passenger submarine can be improved by increasing intersection angle of seatbelt anchor and rotation amount of seatbelt buckle. Based on these results, this paper proposes a new invention of seatbelt buckle and anchor that can improve rear passenger submarine. One is seatbelt buckle that can be detached from stopper to prevent rotation and the other is seatbelt anchor that can be changed the structure so as to incline forward during crash. Finally we proved that submarine of rear female passenger can be improved by the effectiveness of new inventions.

• 대한두경부종양학회지
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• 제32권2호
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• pp.79-83
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• 2016

Chyle fistula is one of the complications of neck dissections. Although immediate surgical repair seems to be the best choice when chyle leakage is observed during the operation, some operators can be embarrassed when chyle leakage is heavy and not controlled during surgery. In this case, chyle leakage was occurred after extensive resection of lymph nodes in left level IV, and was not controlled in any way. The clavicular head of sternocleidomastoid muscle was dissected and inferior-based muscular flap was rotated to cover the suspected region of fistula orifice. Amount of drainage was checked less than 20 ml per day in the following days, and drain tube was taken out on the 3rd postoperative days. We present the technique using the inferior based sternocleidomastoid muscle flap for intraoperative management of chyle leakage not easily controlled.

• The Journal of Korean Physical Therapy
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• 제31권1호
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• pp.24-30
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• 2019

Purpose: This study compared the effectiveness of three methods, fascial distortion model (FDM), myofascial release (MFR), self-myofascial release (SMR), on the neck range of motion and pain. Methods: In this study, the collected data were processed statistically using SPSS version 22.0 for Windows. Descriptive statistics were used to analyze the general characteristics of the subjects. Repeated measure ANOVA was conducted to analyze the range of motion of the neck of the group and VAS, and Contras was used to see the difference in significance over time. One-way ANOVA was used to compare the differences among the groups and a post-hoc test was used. The significance level (${\alpha}$) was 0.05. Results: In the range of motion, the flexion and extension of the neck, right rotation, and left rotation were significantly different in the SMR, FDM, and MFR groups. The right lateral flexion showed significant differences in the FDM, MFR, and SMR groups. The VAS was similar in the groups at 2 and 4 weeks, but there was a significant difference among the FDM, MFR, and SMR groups at 6 weeks. Conclusion: In this study, MFR and MSR as well as FDM were effective in controlling the range of motion and pain control of the neck. Further studies will be needed to determine the effects of long-lasting treatments other than pain control. These studies and the present study will be used as a basis for ongoing research into the duration and method of application for musculoskeletal therapies.

• Journal of Photoscience
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• 제9권2호
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• pp.51-54
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• 2002

We propose a novel mechanism (Twist Sharing Mechanism) for the cis-trans photoisomerization of rhodopsin, based on the molecular dynamics (MD) simulation study. New things devised in our simulations are (1) the adoption of Mt. Fuji potentials in the excited state for twisting of the three bonds C9=C10, C11=C12 and C13=14 which are modeled using the detailed ab initio quantum chemical calculations and (2) to use the rhodopsin structure which was resolved recently by the X-ray crystallographic study. As a result, we found the followings: Due to the intramolecular steric hindrance between 20-methyl and 10-H in the retinal chromophore, the C12-C13 and C10-C11 bonds are considerably twisted counterclockwise in rhodopsin, allowing only counterclockwise rotation of the C11 =C12 in the excited state. The movement of 19-methyl in rhodopsin is blocked by the surrounding three amino acids, Thr 118, Met 207 and Tyr 268, prohibiting the rotation of C9=C10. As a result only all-trans form of the chromophore is obtainable as a photoproduct. At the 90$^{\circ}$ twisting of C11=C12 in the course of photoisomerization, twisting energies of the other bonds amount to about 20 kcal/mol. If the transition state for the thermal isomerization is assumed to be similar to this structure, the activation energy for the thermal isomerization around C11=C12'in rhodopsin is elevated by about 20 kcal/mol and the thermal isomerization rate is decelerated by 10$\^$-14/ times than that of the retinal chromophore in solution, protecting photosignal from the thermal noise.

• 로봇학회논문지
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• 제13권2호
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• pp.113-120
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• 2018

To fly a drone or unmanned aerial vechicle(UAV) safely, its pilot needs to maintain high situation awareness of its flight space. One of the important ways to improve the flight space awareness is to integrate both the global and the local navigation map a drone provides. However, the drone pilot often has to use the inconsistent reference frames or perspectives between the two maps. In specific, the global navigation map tends to display space information in the third-person perspective, whereas the local map tends to use the first-person perspective through the drone camera. This inconsistent perspective problem makes the pilot use mental rotation to align the different perspectives. In addition, integrating different dimensionalities (2D vs. 3D) of the two maps may aggravate the pilot's cognitive load of mental rotation. Therefore, this study aims to investigate the relation between perspective difference ($0^{\circ}$, $90^{\circ}$, $180^{\circ}$, $270^{\circ}$) and the map dimensionality matches (3D-3D vs. 3D-2D) to improve the way of integrating the two maps. The results show that the pilot's flight space awareness improves when the perspective differences are smaller and also when the dimensionalities between the two maps are matched.