• Asian-Australasian Journal of Animal Sciences
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• 제15권11호
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• pp.1527-1530
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• 2002

Factor analysis was applied to the phenotypic correlation matrix of 15 linear type traits (scored linearly 1 to 50 points) for 2035 Holstein cows of 38 sires computed from data collected between 1988 and 1992 in Beijing Shuangqiao Farm and Beijing Xijiao Farm. The 15 linear type traits were stature, body strength, body depth, dairy form, rump angle, rump length, rump width, rear leg side view, foot angle, fore udder attachment, rear udder height, rear udder width, udder cleft, udder depth and teat placement rear view. The first four components accounted for 49.1% of the total variance in type scores. Factor 1 reflected strong cows, with deep bodies, with long and wide rumps, and tall in stature. Factor 2 reflected cows with well attached fore udders, wide rear udders and whose udders were supported by strong suspensory ligaments with close teat placement. Factor 3 reflected cows with good dairyness, sickled in the hocks, high rear udders and udder floors above the hocks. Factor 4 reflected cows with sloping rumps from hooks to pins and with steep foot angle. Principal component and factor analyses are useful to clarify the relationships among type traits.

• 대한통합의학회지
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• 제6권2호
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• pp.1-16
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• 2018

Purpose : This meta-analysis was aimed at guiding future research in stroke treatment and to provide real-world data relating to the effects of aquatic exercise therapy on balance in patients with chronic stroke. Methods : We performed a meta-analysis comprising 22 studies involving aquatic exercise therapy performed between 2006 and 2017. A meta-analysis software program was used to calculate the mean effect size, effect size by intervention, and effect size by outcome. We also performed a meta-regression analysis and an analysis of publishing bias. Results : The mean effect size was 0.563. The effect size by outcome was observed to be the largest for the functional reach test, followed by the Berg balance scale, balance equipment, the Timed Up and Go test and one leg standing. Meta-regression analysis showed that effect size increased with an increase in the duration, number, length of exercise session. Conclusion : Aquatic exercise therapy appears to show a moderate effect on balance in patients with chronic stroke. A meta-analysis is warranted for further research to determine the effects of aquatic exercise on walking, muscle strength, and range of motion.

• 대한임상검사과학회지
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• 제52권1호
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• pp.36-44
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• 2020

With the advent of westernized diet and a lack of exercise, young female college students are paying more attention to their bodyweight and health. Whole-body vibration has been demonstrated to be a suitable training method for improving knee extension maximal strength in young female athletes, as well as the gait performance in elderly women. This study aimed to evaluate the effects of a vertical vibration intervention on the physical fitness and postural balance in young females. Fifty-four young women were recruited; all subjects were randomly assigned to the intervention group and control group. The intervention group underwent vertical vibration with a platform for 12 weeks. The results showed that body mass index and body fat percentage had decreased (P<0.05). In addition, their muscle endurance as indicated by a sit-up test and their flexibility as indicated by a sit-and-reach test were both increased. With regard to postural balance, their 30-second sit-to-stand and timed up and go test results were improved. At the same time, their mean single-leg stance with eyes closed time increased (P<0.05). However, there were no significant differences, meanwhile, for the control group. Overall, the results showed that the whole body vibration (WBV) intervention had some beneficial effects on physical fitness and postural balance in young women.

• 대한물리치료과학회지
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• 제24권1호
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• pp.22-28
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• 2017

Purpose: The purpose of this study was to investigate the changes in the activity of the thigh muscle(rectus femoris, vastus medial/ lateralis, hamstring medial/lateralis) which are caused by the change cf lower extremity muscle activity to speed and inclination during forward and backward walking on the treadmill. Method: Twenty healthy young adults were recruited. The subjects were given a warm-up for 1 minute at the speed of 2.0km/h before exercise, and 2km/h to 4km/h from 10% to 4km/h in the frontal and backward walking. Result: In the present study, it was found that the muscle activity of the lateral broad and inward wide muscles increased when the treadmill was backward for 40 seconds without training. And the femur and the muscle were significantly different from 10% to 4km/h(p<.05). Conclusion: These findings suggest that in the treadmill, it is effective in increasing the leg strength in the backward walking than in the forward walking. And it was concluded that muscle activity increased at 4km/h when the speed was 2km/h when backward walking.

• 항공우주시스템공학회지
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• 제9권4호
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• pp.55-61
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• 2015

In this study, we peformed optimal design of a composite skid landing gear, one of the solid spring shock absorbers, for light vertical takeoff and landing aircraft. Although a solid spring type has poor energy dissipation capability, it is commonly used for light aircraft where sink speeds are low and shock absorption is non-critical in terms of simplicity, low cost and weight reduction. In this paper, design parameters of solid spring such as sink speed, gear leg length, deflection and landing load factor were reviewed. In order to meet structural requirements such as deflection and strength, finally, we conducted optimal design of the composite skid landing gear for VTOL UAV using genetic algorithm and pattern search algorithm.

• The Korean Journal of Physiology and Pharmacology
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• 제19권4호
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• pp.341-347
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• 2015

This study analyzed the effect of regular Taekwondo training for 16 weeks on physical fitness and growth index depending on different IGF-1 gene polymorphisms. The subjects of the study were 44 male students who were 8 year years old. The IGF-1 gene showed the highest frequency of 18 CA repeat (190 bp) in 50% of subjects, and was found in the homozygote (n=11), heterozygote (n=22) and non-carriers (n=11). The results of the physical fitness and growth index among the gene polymorphism groups indicated no significant differences but the expected height of the non-carrier group was significantly high (p<0.05). After Taekwondo training, the homozygote group and the non-carrier groups demonstrated significant (p<0.05) increase in grip strength and in time in the standing with one leg while closing eyes test, respectively. Only the homozygote group had a significant (p<0.05) increase in thigh circumference. IGF-1 concentration significantly (p<0.05) increased in the heterozygote group, while HOMA-IR significantly (p<0.05) decreased in the homozygote group. Furthermore, there was a significant (p<0.05) decrease in glucose in both the homozygote and the non-carriers groups. The difference between physical fitness and growth index depending on the IGF-1 gene polymorphism after Taekwondo training did not show consistent impact.

• 터널과지하공간
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• 제8권4호
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• pp.261-274
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• 1998

이 연구에는 가축성 강재지보에 대한 실내실험 및 현장실험 결과가 제시된다. 시험지보는 단위중량이 25.8kg/m인 Gloken profile U 빔 3매를 조립하여 제작되었다. 양단이 힌지로 지지되는 반원형 및 아치형 지보에 대한 정역학적인 해석이 실시되었다. 실험된 U빔의 형상계수는 1.35이었고 지보형태에 따른 2차 소성힌지의 위치를 산정하였다. 천장부에서 단일집중하중을 받는 아치형 지보의 내하력을 조사하여 이를 지보 각주 길이의 함수로 나타내었다. U 빔 연결부의 결합토크를 변화시키는 실물크기 지보시험을 수행하여 시험지보의 가축특성을 파악하였으며, 결합토크를 설계하는 방법을 연구하였다. 결합토크가 21kg.m 인 시험지보를 현장에 설치하고 계측한 결과 전형적인 가축현상을 관찰할 수 있었다.

• 대한물리의학회지
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• 제13권4호
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• pp.51-58
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• 2018

PURPOSE: This study was conducted to determine if the Harrison hip score (HHS), a tool for assessing hip joint function, and the Burg balance scale (BBS), a general balance assessment tool, actually reflect the balance ability of total hip arthroplasty (THA) patients 3 months after surgery. In addition, this study investigated the initial weight distribution strategy for bilateral lower extremity after THA surgery to understand the balance of THA patients. METHODS: Fourteen 3-month THA patients performed static dual standing and sit-to-stand (STS) tasks. Ground reaction forces on each leg were collected to calculate the weight distribution symmetricity (SWD), and the HHS, functional HHS (f-HHS), and BBS were evaluated. Correlation analyses between SWD and the HHS (also f-HHS) and BBS were then applied to the THA patients. RESULTS: The correlations between functional evaluation tools (HHS, f-HHS, BBS) and SWD were weak strength for the static balance task, but moderate for the dynamic STS task. Among the evaluation tools used in the present study, f-HHS was most useful for evaluation of dynamic balance ability. CONCLUSION: The results suggest that use of HHS, f-HHS, and BBS as functional evaluation tools does not provide meaningful information regarding balance ability, but that they are useful for evaluating dynamic balance ability of THA patients. The dynamic balance ability at 3 months after THA seems to be under development.

• PNF and Movement
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• 제9권3호
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• pp.19-24
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• 2011

Purpose : The purpose of this study was to analyze the effect of PNF lower extremity flexion pattern on the eletromyographic (EMG) activity in rectus abdominis, internal oblique abdominal, external oblique abdominal, erector spinae. Methods : Twenty-six healthy adults volunteered to participate in this study. Subjects were required complete following two PNF lower extremity patterns; flexion-adduction-external rotation with knee flexion (D1) and flexion-abduction-internal rotation with knee flexion (D2). A paired t-test was used to determine the influence of the PNF two patterns on muscle activity for each muscle and descriptive statistics was used to determine local/global muscle ratio. Results : The D1 pattern was showed significant rectus abdominis (p<.05) and Median of internal oblique/rectus abdominis ratio was 2.23 and internal oblique/external oblique ratio was 1.53. The D2 pattern showed significant erector spinae (p<.05) and Median of internal oblique/rectus abdominis ratio was 3.06 and internal oblique/external oblique ratio was 1.72. Conclusion : The D1 pattern made rectus abdominis activation increase. The D2 pattern made erector spinae activation increase. As compared D1 and D2 pattern on trunk muscle activation, it's will be useful decision making for the trunk muscle strength and stabilization.

• Applied Microscopy
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• 제51권
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• pp.11.1-11.9
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• 2021

Spider capture silk is a natural scaffolding material that outperforms most synthetic materials in terms of its combination of strength and elasticity. Among the various kinds of silk threads, cribellar thread is the most primitive prey-capturing type of spider web material. We analyzed the functional organization of the sieve-like cribellum spigots and specialized calamistral comb bristles for capture thread production by the titanoecid spider Nurscia albofasciata. The outer cribellar surface is covered with thousands of tiny spigots, and the cribellar plate produces non-sticky threads composed of thousands of fine nanofibers. N. albofasciata cribellar spigots are typically about 10 ㎛ long, and each spigot appears as a long individual shaft with a pagoda-like tiered tip. The five distinct segments comprising each spigot is a defining characteristic of this spider. This segmented and flexible structure not only allows for spigots to bend individually and join with adjacent spigots, but it also enables spigots to draw the silk fibrils from their cribella with rows of calamistral leg bristles to form cribellar prey-capture threads.