• 소음진동
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• 제10권2호
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• pp.247-253
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• 2000

The evaluation of the ride quality had been performed by the subjective method before ISO2631(International Organization for Stadard 2631) and BS6841(British Standard 6841) was precented, but many research programs have been performed by the objective method after that. On this study, the ride quality was evaluated related with the objective method which considered the vibration which the human body feels on the driver's seat while driving on the road. In particular, we made the shock absorber nonlinear model and also selected the suitable shock absorber in the part of the vibration which the human body feels into the simulation. The shock absorber of suspension was dealt with 3 cases respectively with the front wheel and rear wheel. The vibration of the car driving on the road can be transferred to the wheel, the suspension, the vehicle body, the seat and the human body. The signal which was gained from the seat(hip) and the floor(foot) of the human body was changed to the vibration signal which the human body felt through using the frequency weighting function. And then the performance of the shock absorber was calculated through the statistic processing.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.411-417
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• 2009

본 논문은 지능형 환경에 적합하도록 사용자의 자유를 제한하지 않는 실시간 신체 부위 추적 시스템의 구현에 관해 다룬다. 본 시스템은 기존의 신체 부위 추적 시스템과 달리 소매의 길이에 제약 없이 긴 소매, 반 소매 모두 인식할 수 있도록 함으로써 시스템의 generality를 높였다. 정확한 인식을 위하여, 한 대의 카메라에서 얻어진 이미지에서 손, 머리, 발의 신체 부위를 따로 검출하고 각 신체 부위를 검출할 때 해당 부위에 적합한 특징점을 따로 선택하여 검출하였다. 검출된 2차원의 신체 부위들을 calibrate된 카메라를 이용하여 3차원 자세로 변환하였다. 본 시스템은 실험을 통해 실시간(50fps) 성능으로 향상된 손 추적 성능을 보여주었다.

• 한국생활과학회지
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• 제14권3호
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• pp.475-483
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• 2005

The ready-made clothes for obese women are not manufactured systematically due to the diversity and scarcity of their body shape. In this study, we first analyzed and classified 104 obese women's body shape to select four representative subjects. Then, the four subjects participated in wearing test to evaluate the performance of the jacket patterns which are available in the market and widely-used at the same time. The characteristics of the jacket patterns for obese women were also investigated. As to the highly rated jacket in terms of body motion, it was found that difference between the breast width to axilla and the breadth to anterior midaxilla is larger than the other jackets, and the breast width of front body is wider than what of back width. It was noted, however, that the armhole depth and the width of obese women' jackets should not be determined indirectly by the magnitude of the girth around bust, waist or hip as in the case of regular sized women's. It is because body proportion of obese women is different from that of standard sized women.

• 국제물리치료학회지
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• 제6권2호
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• pp.884-890
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• 2015

This study observed the effects of ankle strengthening exercise and whole body vibration on the balance ability of older adults, thereby intending to provide basic materials for intervention methods aimed at improving older adults' balance ability. The subjects were 20 older adults who had experienced a fall. They were equally divided into two groups. Ankle strengthening training was applied to one group and ankle strengthening training and whole body vibration were applied to the other group, a timed up and go (TUG) test and Tinetti performance oriented mobility assessment (POMA) were performed, and changes in the subjects' limits of stability were observed. The TUG and POMA results significantly differed between before and after the experiment in the angle strengthening training (AST) group and the angle strengthening training with whole body vibration (ASTWV) group. In addition, the interaction between timing and each group was statistically significant. The limits of stability significantly changed after the intervention in both groups. Differences in the posterior and right limits of stability were significant between the AST group and ASTWV group. Therefore, ankle strengthening exercise and whole body vibration improve older adults' balance maintenance and reduce falls or the risk factors for falls in older adults.

• 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.

• 복식
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• 제58권9호
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• pp.166-175
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• 2008

For the structural firefighting protective clothing, it can show a synergy effect when it satisfies smart fabric to block off a harmful environmental element and ergonomics design that apply range of motion of human body and appropriate size system. There are various standards about the structural firefighting protective clothing, but it's difficult to find a rule about movement suitability because the performance of the material holds a lot of the rules. Therefore, the purpose of this study is to propose a scheme to evaluate the current structural firefighting protective clothing and to improve movement suitability by research on the actual condition. For this, the survey about wearer acceptability scale on design and size and about improvement requirements was executed gathering firefighters' opinion. Questionnaire was composed with 23 items about satisfaction on current structural firefighting protective clothing, body suitability, movement suitability, improvement requirement and subjective information. As a results, Korean firefighters demand ergonomics design of structural firefighting protective clothing which to minimize restriction of body movement and to maximize body suitability.

• 정보처리학회논문지B
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• 제18B권1호
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• pp.11-20
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• 2011

Pictorial Structures(PS)는 동적 프로그래밍을 이용하여 인체의 포즈 추적 및 인식 하는 것에 매우 효과적인 방법으로 알려져 있다. 본 논문에서 상반신 포즈는 PS와 Particle filter(PF)에 의한 동적 프로그래밍 기법으로 추적된다. PF와 같은 동적프로그래밍에서 마코프 연쇄 (Markov Chain) 기반 동적 움직임 모델은 높은 자유도를 갖는 상반신 포즈를 예측하기 어려운 단점이 있다. 본 논문에서 제안하는 방법은 키포즈 기반 예측분포이며, 이것은 상반신 실루엣과 키포즈(Key Pose)들 사이의 유사도를 참고하여 파티클(Particle)을 적절히 예측하는 것이다. 실험 결과를 통해 제안된 방법은 기존 방법 성능을 70.51% 향상시킨 것을 확인하였다.

• 한국운동역학회지
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• 제23권2호
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• pp.125-130
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• 2013

Although the electronic body protector has been officially adopted by the World Taekwondo Federation(WTF) in 2006, no scientific information is available about the reliability of its performance. The purpose of this study, therefore, was to investigate the relationship between the impact value of electronic body protector and the impact force of force platform. Male collegiate Taekwondo athletes([MCTA], n=21) and male collegiate Taekwondo students([MCTS], n=20) volunteered to participate in the study. Each subject performed the apchagi, dollyeochagi and dwichagi on the force platform and the electronic body protector. At the apchagi, it showed that MCTS(about 4,700 N) generated more maximum kick force than MCTA(about 3,900 N), but it expressed that MCTA(about 5,300 N) generated more maximum kicking force than MCTS(about 4,400 N) at the dwichagi. At the apchagi and the dwichagi, it indicated the high coefficient of correlation(over r=.8) which supports higher explanation force the relationship between the impact value of electronic body protector and the impact force of force platform, but there was no statistically significant difference at the dollyeochagi.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2000년도 제32회 추계학술대회 정기총회
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• pp.332-340
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• 2000

Friction properties of automotive brake pads containing different types of abrasivess were investigated. Five different abrasives, including o-quartz, magnesia, magnetite, alumina, zircon, were employed in this investigation and size effects of the abrasives on friction characteristics were also studied using 1, 50, 140$\mu\textrm{m}$ size zircon. Experimental results showed that the hardness and size of these abrasive particles were strongly related to friction behaviors and wear mechanisms. Harder and smaller abrasives showed higher friction coefficient and more wear. The surfaces of friction materials with different sizes of abrasives showed that two different modes of abrasion (two-body and three-body abrasion) appeared during sliding. Considering the above results, abrasive materials were thought to destroy transfer film and the extent of the destruction depends on the types and sizes of abrasive particles. A mechanism of the wear mode transition (two-body to three body abrasive motion) was suggested considering the binding energy and friction energy in terms of abrasive particle size.

• 대한조선학회논문집
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• 제56권4호
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• pp.327-334
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• 2019

Recently, there has been a growing interest in artificial supercavitation as a way to reduce friction drag of submerged vehicles. A cavitator plays an important role to generate the supercavity, so many studies have focused on the case of cavitator only. However, the body shape behind the cavitator affects the growth of the supercavity and this effect must be considered for evaluating the overall performance of the system. In this work, we conducted experimental investigation on artificial supercavitation generated by different combinations of the cavitator and body. We observed the supercavity pattern by using a high-speed camera and measured the pressure inside the cavity by using an absolute pressure transducer. We estimated the relation between the amount of injected air and the supercavity shape for different combinations. In summary, the disk type cavitator generates larger supercavity than that of the cone and ellipsoidal cavitators, but cavity development speed is relatively slower rather than the others. Furthermore, fore body angle plays an important role to generate the supercavity enveloping the entire body.