• 한국산학기술학회논문지
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• 제15권5호
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• pp.3114-3120
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• 2014

산업현장에서 사용되는 무선 비상호출 스위치의 성공적인 운영을 위해서는 지속적인 전원의 공급이 이루어져야 한다. 본 논문은 배터리가 필요 없는 무선 스위치에 적용할 수 있는 전자기 유도방식의 초소형 에너지 하베스팅 메커니즘 개발 및 구현된 메커니즘의 성능 실험 결과를 보여주고 있다. 연구결과로 단 방향 누름 동작과 2mm 이동거리의 제한조건 내에서, 유도기전력을 생성하는 새로운 메커니즘이 제시됐다. 또한, 구현된 메커니즘의 전자기 유도 발전 출력 성능 실험결과로 VDC $4.5V{\pm}25%$(도달시간 1.2msec), 2.5V 이상 전압의 발전시간이 65ms가 됨을 보여주고 있다.

• 근관절건강학회지
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• 제14권2호
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• pp.149-157
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• 2007

Purpose: The purpose of this study was to identify the effect of BeHaS exercise program on the upper body function(muscle strength, muscle endurance, flexibility) in middle-aged women. Method: Middle-aged women were recruited in the community the study was conducted from August 2005 to December 2005. Twenty-two experimental subjects were selected from P area, eighteen control subjects were selected from A area. The experimental group carried out the program two times a week for 12 weeks. Muscle strength(grip strength, pinch strength), muscle endurance (push-up), flexibility were measured. Data were analyzed with $x^2$-test, t-test, and ANCOVA using SPSS WIN 11.5. Results: 1) Left grip strength and right pinch strength of the experimental group were significant differences after the BeHaS exercise program. 2)Muscle endurance of the experimental group(t=3.14, p=0.015) was significant difference after the BeHaS exercise program. 3) Left and right flexibility showed no significant differences after the BeHaS exercise program. Conclusion: The results suggest that BeHaS exercise program would partially improve upper body function of middle-aged women. Further studies are necessary in order to determine the effects of flexibility after BeHaS exercise program.

• 한국강구조학회 논문집
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• 제15권6호통권67호
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• pp.621-628
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• 2003

스터드 전단연결재는 강합성 구조에서 가장 많이 사용되는 전단연결재인데 현재는 주로 22mm 직경까지를 사용하고있다. 시방규정에서 제시하고 있는 적용범위의 확대를 위해서 25mm 이상의 대직경 스터드 전단연결재에 대한 연구가 필요하다. 현재의 전단연결재 설계 범위를 넘어서는 대직경 스터드 전단연결에 대한 push-out 실험을 통해서 피로거동을 검토하고 기존 설계식과의 비교를 수행하였다. 25, 27, 30mm 직경의 스터드에 대한 전단실험을 통해서 탄성영역에서의 전단강성을 평가하여 정적 실험결과와 비교하였다. 피로 하중을 받는 대직경 스터드의 피로거동을 잔류 슬립과 하중-슬립 곡선으로 설명하였다. 용접부 피로균열의 발생시점을 변위진폭으로부터 유추하는 것이 타당한 것으로 밝혀졌다. 기존 시방규정의 S-N 곡선과의 비교를 통해서 대직경 스터드 전단연결재의 피로 수명은 현재의 설계 규정을 준용해도 무방한 것으로 나타났다.

• 기본간호학회지
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• 제4권2호
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• pp.267-282
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• 1997

This study was to test the relationship between regular physical exercise and physical fitness in nursing students. These subjects were 54 volunteers who agreed with intention of this study and were composed of 24 active group and 30 non-active group. The selected physical fitness tests were grip strength and back strength for measuring muscular strength, sargent jump and standing broad jump for measuring power, push-up, sit-up, and heart rate for measuring total endurance, reaction time and side step test for measuring agility, stick test and stork stand for measuring balance, and trunk flexion and trunk extension for measuring flexibility. The conclusion acquired was as follows : 1) Grip strength had significant difference between active group of $29.5{\pm}5.9kg$ and non-active group $25.4{\pm}7.2kg$(t=2.283, p=.027), and back strength between active group of $54.1{\pm}13.7kg$ and non-active group of $44.7{\pm}15.7kg$(t=2.310, p=.025), 2) Sargent jump was lower with non-active group($44.9{\pm}8.6cm$) than with active group($45.3{\pm}8.8cm$), however, was not significant(t=.182, p=.856). Standing broad jump was significantly lower with non-active group of $161.3{\pm}28.7cm$ than with active group of $191.4{\pm}27.0cm$(t=3.939, p=.000). 3) Push-up showed significant difference between active group of $25.3{\pm}12.3times$ and non-active group of $11.5{\pm}5.1times$(t=5.572, p=.000), and sit-up between active group of $21.8{\pm}7.4times$ and non-active group of $17.1{\pm}5.8times$(t=2.631, p=.011), and heart rate between actvie group of $110.5{\pm}12.8$beats/min and non-active group of $121.5{\pm}9.5$beats/min(t=-3.648, p=.001). 4) Reaction time was significantly higher with non-active group of $.300{\pm}.051sec$ than with active group of $.341{\pm}.041sec$(t=-3.285, p=.002). Side step test was lower with non-active group($8.8{\pm}1.1times$) than with active group($9.2{\pm}1.2times$), however, was not significant (t=1.309, p=.196). 5) Stick test showed not significant difference between active group of $25.8{\pm}14.8sec$ and non-active group of $30.7{\pm}17.9sec$(t=-1.058, p=.295), and stork stand between active group of $4.5{\pm}3.2sec$ and non-active group of $3.7{\pm}3.5sec$(t=.918, p=.363). 6) Trunk flexion came out not significant difference between active group of $14.2{\pm}5.0cm$ and non-active group of $15.8{\pm}7.3cm$(t=-.927, p=.358), and trunk extension between active group of $67.1{\pm}6.5cm$ and non-active group of $67.3{\pm}6.6cm$(t=-.140, p=.889). 7) Power was shown to be significantly related to total endurance(r=.717, p=.000 ; r-.739, p=.000). 8) Total endurance was shown to be significantly related to agility(r=-.752, p=.000 ; r=.684, p=.000 ; r=-.664, p=.000 ; r=.598, p=.002 ; r=.864, p=.000 ; r=-.536, p=.007). These results suggest that regular physical exercise is effective in promoting and maintaining physical fitness. As the further study, it is necessary to reinvestigate the effect with more refined design.

• International Journal of Railway
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• 제1권4호
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• pp.143-148
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• 2008

This paper is the output of a collaborative European project concerning the barrier free accessibility for disabled persons to regional and long distance trains in Europe. Disabled people represent around 13% of the population in Europe. This is approximately 63 million people. The range of disabilities includes people with reduced mobility including wheel chair users, viewing and hearing impaired people and other forms of impairment. Improving accessibility aims at contributing to the provision of public transport services to all citizens in an equitable way. The purpose of the project was to analyse and to evaluate the existing solutions at selected European railways for all required modules at the entrance (doors, information and safety solutions), to derive a design concept, to develop a mock-up in meeting the needs of rail travellers with the above mentioned impairments and to test it with user groups. The project also aims at deriving components for the determination of standards. The EUPAX Design Mock-up test was performed to verify the advantages of the layout of the train segment including the different modules such as access area (including the access door, gaps between platform and train as well as boarding aid devices), entrance vestibule, information systems inside and outside the train, emergency facilities, toilet with all conveniences and the additional test arrangements regarding push buttons, steps and emergency equipment. For this purpose a questionnaire was developed for the assessment of the EUPAX segment and the additional test arrangements. With the help of this questionnaire it was possible to execute a quantitative and qualitative evaluation. During three test phases 67 experts and handicapped persons from 6 countries have evaluated the Industrial Design mock-up based on this questionnaire. The test group covered persons from North (Denmark) to the South (Italy) and from the West (Spain) to the Middle of Europe (Germany). This is especially important for the generalization (harmonisation) of the results for all European countries. According to COST 335 the information for people with reduced mobility should be clear, concise, accurate and timely. So that all information can be received from persons, they must be transferred on at least two of the three possible ways (acoustical, visual, tactile), a so called "2-sense-principle". Based on the results ergonomic specifications/ solutions for the ergonomic design of the access area, the acoustic, visual and tactile information and the emergency devices including the emergency communication system were developed, related to the benefiting passenger groups.

• 한국안광학회지
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• 제14권1호
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• pp.115-119
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• 2009

목적: 본 연구는 조절력 및 조절반응과 조절용이의 상관관계를 알아보고자 하였다. 방법: 특별한 안질환이 없고 노안이 진행되지 않는 20~40대의 성인 남녀 61명을 대상으로 하였다. 원거리시력을 완전교정한 후 조절력은 Push-Up 방법으로 검사하였고, 조절반응량검사와 조절용이성 검사는 각각 잭슨크로스실린더 ${\pm}$0.25D와 flipper +2.00/-2.00D를 이용하였다. 결과: 단안, 양안시 상태에서 조절력과 조절반응, 조절용이의 상관관계는 유의성이 없었으며, 양안시 상태에서 기대값과 다르게 나타난 안구의 수는 총 61안 중 23안(37.7%)로 이들 중 조절력이 12안(19.6%), 조절반응이 9안(14.7%), 조절용이가 2안(3.2%)으로 나타났고, 조절력과 조절반응이 동시에 나타난 경우가 4안(6.5%), 조절력과 조절용이가 동시에 나타난 경우는2안(3.2%), 조절력과 조절반응, 조절용이 3가지 모두 기대값과 다르게 나타난 경우는 없었다. 결론: 조절기능 평가 시 조절력검사와 조절반응검사, 조절용이성 검사는 각각 시행되어야 하며 조절기능의 결함이 의심 될 때에는 이들 항목의 평가가 반드시 필요하다.

• 한국공간구조학회:학술대회논문집
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• 한국공간구조학회 2008년도 춘계 학술발표회 논문집
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• pp.171-178
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• 2008

This paper is concerned with the development of a measurement system using field measuring device which will give the membrane stress of the membrane structures. Up to this point, several techniques on measurement of membrane stresses has been proposed and some have been used in the fields, but accuracy of the measured stresses to be far from reliable one. Such situation has not been changed until recent days, we do not have the measurement device on which we can depend. On top of that, due to the different properties in cross directions for material of the membrane, the stress in the warp direction is different from that in the fill one. A new method is proposed to measured membrane stresses in two different direction separately, where instead of membrane stresses directly, an external force perpendicular to the membrane to be applied. A portable device can measure the applied force and the displacement. A special testing bed to be fabricated to accommodate $50cm{\times}50$ manbrane specimen which can apply 5 ton load in two orthogonal direction. A special device using push-pull gage was developed. To measure the membrane stresses in warp and fill direction separately, a different length of the tips are used. The measuring device which can called tension meter, can be calibrated on the testing bed, and optimized the length and shape of tip.

• Journal of Power Electronics
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• 제11권5호
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• pp.621-631
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• 2011

In space qualified DC-DC converters, optimization of the following electrical characteristics is of greater interest in comparison with other specifications; power loss/efficiency, output voltage ripple and volume/weight. The main goal of this paper is to present an appropriate solution for optimizing the above mentioned characteristics. For this purpose, a comprehensive power loss model of a DC-DC converter is fully developed. Proper models are also demonstrated for assessment of the output voltage ripple and the utilized transformer volume as the bulkiest component in a DC-DC converter. In order to provide a test bed for evaluation of the proposed models, a 50W push-pull DC-DC converter is designed and implemented. Finally, a novel cost function with three assigned weight functions is proposed in order to have a trade-off among the power loss, the output voltage ripple and the utilized transformer volume of the converter. The cost function is optimized for applications in which volume has the highest priority in comparison with power loss and ripple. The optimization results show that the transformer volume can be decreased by up to 51% and this result is verified by experimental results. The developed models and algorithms in this paper can be used for other DC-DC converter topologies with some minor modifications.

• 국제물리치료학회지
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• 제10권1호
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• pp.1706-1710
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• 2019

Background: Despite frequent shoulder injuries of rotator cuff muscle of golfers by the result of overuse and poor swing mechanics, there is little research on shoulder specific rehabilitation exercises for injured rotator cuff muscle and golf swing Objective: To examined the effect of rehabilitation exercise for golfers on the X factor and ground reaction force (GRF) according to phase of the golf swing. Design: Crossover study Methods: The participants were 13 amateur golfers selected for a 4 week rehabilitation exercise for golfers. A rehabilitation exercise for golfers consisting of 5 steps and 4 items (sleeper stretch, full side plank, push up to plank, high plank knee unders) were applied to all participants. A three dimensional motion analyzer and force platform (SMART-E, BTS, Italy) were used to measure the X factor (angle between shoulder and pelvis at top of back swing) and GRF according to phase of the golf swing. All dependent variables were measured before and after exercise. The collected data was analyzed using the paired t test and SPSS 21.0. Results: The GRF had a statistically significant increase in the impact phase and ratio impact/weight after rehabilitation exercise for golfers (p<.05). The X-factor, GRF in top of back swing and finish were no significant differences between before and after exercise (p>.05). Conclusions: These results suggested that rehabilitation exercise for golfers was effective for increasing GRF in the impact phase and ratio impact/weight for amateur golfer.

• The Journal of Korean Physical Therapy
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• 제34권1호
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• pp.6-11
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• 2022

Purpose: This study investigated the muscle activity of the lower trapezius (LT) during three different shoulder flexion exercises. Methods: Twenty-three subjects between 20 and 25 years of age were enrolled. The subjects were asked to perform three different shoulder flexion exercises: 1) shoulder flexion in prone (SFP), 2) shoulder flexion in push-up with a swiss ball (SFPUS) and 3) shoulder flexion in a quadruped position with a swiss ball (SFQPS) in random order. The muscle activity of LT during each shoulder flexion exercise was measured by using surface electromyography. The muscle activity of LT was compared using one-way analysis of variance (ANOVA) and Bonferroni post hoc test among three different shoulder flexion exercises. The statistical significance level was set at α=0.01. Results: The muscle activity of LT was significantly different among three different shoulder flexion exercises (SFP, SFPUS, and SFQPS). The LT muscle activity with SFQPS exercise was greater than SFP and SFPUS exercises (p<0.01). There was no significant difference in LT muscle activity between SFP and SFPUS exercises (p>0.01). Conclusion: The LT muscle activity was greater during SFQPS than SFP and SFPUS. Therefore, SFQPS exercise can be recommended for selectively activation of LT muscle.