• 제목/요약/키워드: Jumping

검색결과 415건 처리시간 0.024초

콤바인 선별손실(選別損失) 적정화(適正化)를 위(爲)한 요동(揺動)체의 특성(特性)과 선별성능(選別性能)에 관한 연구(硏究) (Study on the Characteristics and Separating Performance of Oscillating Sieve for Optimization of Separating Losses of Combine)

  • 김상헌;남상일;류수남
    • Journal of Biosystems Engineering
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    • 제9권2호
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    • pp.48-57
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    • 1984
  • To analyze the grain transport velocity, which is valuable for optimizing the separation losses, an oscillating appratus for sieve was designed. The grain transport velocity was measured in each combination of three amplitude levels, three rpm levels and four projection angle levels. To analyze the grain transport velocity theortically, two computer programs were developed. And the results from experiment and theoretical analysis were compared. 1. The grain transport velocity was increased with the projection angle of oscillating sieve. Especially when the projection angle is higher than $45^{\circ}$ the grain transport velocity on the flat-plate was not increased but on the racked surface was increased persistently. 2. The grain transport velocity was increased linearly with the frequency of oscillating motion. The speed of driving link must be higher than 350 rpm at 24mm amplitude, 250 rpm at 36 mm amplitude to transport the grain efficiently. 3. The grain transport velocity was increased with the amplitude of oscillating motion. But if the amplitude was smaller than interval of racks, the grain on the racked surface was not transported, even though the projection angle or the speed of revolutionary link was increased. 4. The transport characteristics of a grain varied with the amplitude and projection angle. Especially in the range of 1.5 < K < 2.3 at $45^{\circ}$ projection angle the transportation of grain was successful and the grain motion consisted of sliding movement (forward, backward) and jumping movement, which is considered recommendable for separating process of a combine sieve. 5. The results from theoretical analysis were approximately in accord with that from experiment.

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드롭랜딩 시 낙하높이에 대한 시각 및 인지 정보가 착지 전략에 미치는 영향 (The Effect of Visual & Cognitive Information of Landing Height on Landing Strategy during Drop Landing)

  • 은선덕;양종현;김용운;강명수;곽창수
    • 한국운동역학회지
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    • 제22권4호
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    • pp.405-411
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    • 2012
  • The purpose of this study was to determine the effects of landing height information on landing strategy during a drop landing. Ten healthy male subjects(age: $22.1{\pm}1.9year$, height: $178.4{\pm}7.8cm$, mass: $75.3{\pm}9.4kg$) participated in this study. Each participant was asked to jump with both legs off a 40 cm high box on one of the three plates with different thickness (0 cm, 13 cm, 26 cm). In the first condition, subjects were given both cognitive and visual information about the jumping heights. In the second, they were given only cognitive information without visual one, and in the third, no information about the height was provided to subjects. (Only the data collected from the 40 cm height landing were analyzed and reported in the present study.) The results showed that landing strategies during a double-leg drop landing from 40 cm height were not significantly affected by visual and cognitive information blockages. Also, there were no statistically significant differences in landing strategies between the three conditions even though the mean differences attained in this study seemed to warrant further studies investigating the relationship between landing strategies and cognitive information.

8주간의 체중을 이용한 저항운동 시 전신진동 유·무에 따른 노인 여성하지의 발바닥쪽굽힘근의 생체역학적 특성 변화 (Changes in the Biomechanical Properties of Ankle Plantarflexors Following 8-week Resistance Training with or without Whole-Body Vibration in Older Women)

  • 한보람;이대연;정시우;이해동
    • 한국운동역학회지
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    • 제24권4호
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    • pp.399-415
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    • 2014
  • The aim of this study was to investigate the effect of resistance training with and without whole-body vibration(WBV) on the biomechanical properties of the plantarflexor in the elderly women (>60 yrs., n=35). Thirty-five volunteers were randomly assigned to a resistance training with WBV group (RVT, n=14), a resistance training without WBV (RT, n=11), and a non-training control group (CON, n=10). The RVT and the RT groups participated in the training sessions three times a week for 8 weeks, followed by a 4-week detraining period. The CON group was instructed to refrain from any type of resistance training. To assess strength and activation of the plantarflexor muscles, maximum isometric ankle plantarflexion torque and muscle activation of the triceps surae muscles were measured using dynamometry, twitch interpolation technique and electromyography at four different ankle joint angles. Also, the lower extremity function was assessed by vertical jumping. The measurements were performed prior to, 2 and 8 weeks after the training and after a 4-week detraining period. Following the 8-week training sessions, an increase in the isometric plantarflexion strength was found to be greater for the RVT compared with the RT group (p<.05). Muscle inhibition was significantly decreased after training than before training only for the RVT (p<.05). Following the detraining period, a decrease in isometric plantarflexors strength and a increases in muscle inhibition were significantly less in the RVT compared with the RT group. In conclusion, the exercise with WBV is a feasible training modality for the elderly and seems to have a boosting effect when used with conventional resistance training.

플랫폼 다이빙 앞으로 서서 앞으로 11/2회전 동작의 운동역학적 분석 (A Kinetics Analysis of Forward 11/2 Somersault on the Platform Diving)

  • 전경규
    • 한국운동역학회지
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    • 제23권3호
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    • pp.209-218
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    • 2013
  • This study was to perform the kinetic analysis of forward $1\frac{1}{2}$ somersault on the platform diving. Six men's diving players of the Korea national reserve athletes participated in this study. The variables were analyzed response time, velocity, center of mass (COM), angle, center of pressure (COP) and ground reaction force (GRF) of motion. For measure and analysis of this study, used to synchronized to 4 camcorder and 1 force plate, used to the Kwon3D XP (Ver. 4.0, Visol, Korea) and Kwon GRF (Ver. 2.0, Visol, Korea) for analyzed of variables. The results were as follows; Time factor were observed in maximum knee flexion depending on the extent of use at phase 1 of take-off to execute the somersault. This enabled the subject to secure the highest possible body position in space at the moment of jumping to execute the somersault and prepare for the entry into the water with more ease. Regarding the displacement of COM, all subjects showed rightward movement in the lateral displacement during technical execution. Changes in forward and downward movements were observed in the horizontal and vertical displacements, respectively. In terms of angular shift, the shoulder joint angle tended to decrease on average, and the elbow joints showed gradually increasing angles. This finding can be explained by the shift of the coordinate points of body segments around the rotational axis in order to execute the half-bending movement that can be implemented by pulling the lower limb segments toward the trunk using the upper limb segments. The hip joint angles gradually decreased; this accelerated the rotational movement by narrowing the distance to the trunk. Movement-specific shifts in the COP occurred in the front of and vertical directions. Regarding the changes in GRF, which is influenced by the strong compressive load exerted by the supporting feet, efficient aerial movements were executed through a vertical jump, with no energy lost to the lateral GRF.

Dependence Potential of Tramadol: Behavioral Pharmacology in Rodents

  • Cha, Hye Jin;Song, Min Ji;Lee, Kwang-Wook;Kim, Eun Jung;Kim, Young-Hoon;Lee, Yunje;Seong, Won-Keun;Hong, Sa-Ik;Jang, Choon-Gon;Yoo, Han Sang;Jeong, Ho-Sang
    • Biomolecules & Therapeutics
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    • 제22권6호
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    • pp.558-562
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    • 2014
  • Tramadol is an opioid analgesic agent that has been the subject of a series of case reports suggesting potential for misuse or abuse. However, it is not a controlled substance and is not generally considered addictive in Korea. In this study, we examined the dependence potential and abuse liability of tramadol as well as its effect on the dopaminergic and serotonergic systems in rodents. In animal behavioral tests, tramadol did not show any positive effects on the experimental animals in climbing, jumping, and head twitch tests. However, in the conditioned place preference and self-administration tests, the experimental animals showed significant positive responses. Taken together, tramadol affected the neurological systems related to abuse liability and has the potential to lead psychological dependence.

다양한 지지면에서 균형운동이 경직성 뇌성마비 양하지마비 아동의 대동작기능 및 균형능력에 미치는 효과 (The Effect of Balance Exercise on Various Support Surfaces on the Gross Motor Function and Balance Ability of Children with Cerebral Palsy)

  • 이은정;송주민
    • 대한물리의학회지
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    • 제7권3호
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    • pp.357-365
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    • 2012
  • Purpose : The present study has been performed to find the effects on gross motor function and balance ability of applying a balance exercise program consisting of motions able to stimulate balance-related sensory systems on various support surfaces along with goal-oriented upper extremity tasks to enhance the balance ability. Methods : 10children diagnosed as having spastic diplegia were selected as the subject for this study, of whom 5children were randomly assigned to a control group (CG) and the remainder to a balance exercise group (BEG) to perform the upper extremity task on various support surfaces. Each intervention was executed 30minutes per session with 2sessions a week for 12weeks. To make comparisons before and after intervention, gross motor function measure; standing; demention D(GMFM;D), walking/running/jumping ;demention E (GMFM;E) and pediatric balance scale (PBS) were evaluated. Results : The CG showed a significant difference (p<.05) in GMFM;E. BEG showed a significant difference (p<.05) in GMFM;D as well as GMFM;E and in PBS before and after intervention. BEG showed a significant improvement (p<.05) in GMFM;D and the PBS compared with the CG whereas it did not indicate any statistically significant difference in GMFM;E. Conclusion : According to the results of this study, it has been shown that a balance exercise accompanied by upper extremity task on various support surfaces had an effect on improvement in the gross motor function and the balance ability of children with spastic diplegic cerebral palsy.

Structural evaluation of all-GFRP cable-stayed footbridge after 20 years of service life

  • Gorski, Piotr;Stankiewicz, Beata;Tatara, Marcin
    • Steel and Composite Structures
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    • 제29권4호
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    • pp.527-544
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    • 2018
  • The paper presents the study on a change in modal parameters and structural stiffness of cable-stayed Fiberline Bridge made entirely of Glass Fiber Reinforced Polymer (GFRP) composite used for 20 years in the fjord area of Kolding, Denmark. Due to this specific location the bridge structure was subjected to natural aging in harsh environmental conditions. The flexural properties of the pultruded GFRP profiles acquired from the analyzed footbridge in 1997 and 2012 were determined through three-point bending tests. It was found that the Young's modulus increased by approximately 9%. Moreover, the influence of the temperature on the storage and loss modulus of GFRP material acquired from the Fiberline Bridge was studied by the dynamic mechanical analysis. The good thermal stability in potential real temperatures was found. The natural vibration frequencies and mode shapes of the bridge for its original state were evaluated through the application of the Finite Element (FE) method. The initial FE model was created using the real geometrical and material data obtained from both the design data and flexural test results performed in 1997 for the intact composite GFRP material. Full scale experimental investigations of the free-decay response under human jumping for the experimental state were carried out applying accelerometers. Seven natural frequencies, corresponding mode shapes and damping ratios were identified. The numerical and experimental results were compared. Based on the difference in the fundamental natural frequency it was again confirmed that the structural stiffness of the bridge increased by about 9% after 20 years of service life. Data collected from this study were used to validate the assumed FE model. It can be concluded that the updated FE model accurately reproduces the dynamic behavior of the bridge and can be used as a proper baseline model for the long-term monitoring to evaluate the overall structural response under service loads. The obtained results provided a relevant data for the structural health monitoring of all-GFRP bridge.

The effect of ankle Kinesio taping on range of motion and agility during exercise in university students

  • Eom, Se Young;Lee, Won Jun;Lee, Jae Il;Lee, Eun Hee;Lee, Hye Young;Chung, Eun Jung
    • Physical Therapy Rehabilitation Science
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    • 제3권1호
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    • pp.63-68
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    • 2014
  • Objective: The purpose of this study was to examine the effects of ankle Kinesio taping on range of motion and agility during exercise in university students. Design: Cross-sectional study. Methods: Thirty subjects were randomly allocated to two groups: taping group (n=15) and non-taping group (n=15). All groups underwent the same exercise program including stretching for 30 minutes. The exercise program proceeded in the following order: five minutes of stretching, a 20-minutes exercise program, and additional five minutes of stretching. Of the eight exercise methods suggested by Purcell et al, seven were chosen (lateral shuffle, forward and backward running, agility ladder, figure-of-8, forward jogging while jumping over cones, wall jumps and zigzags); $90^{\circ}$ cuts with lateral shuffle were omitted. The range of motion of ankle dorsiflexion and plantarflexion was measured using the goniometer. Agility was measured using the side hop test. Results: For ankle range of motion, the taping group showed significant differences in dorsiflexion and plantarflexion on both sides (p<0.05). The non-taping group showed significant differences only in left plantarflexion (p<0.05). There was a significant difference in dorsiflexion on both sides between the taping group and the non-taping group (p<0.05). All groups showed significant differences in agility on the left and right ankle (p<0.05). There was a significant difference in left ankles between the taping group and the non-taping group (p<0.05). Conclusions: Kinesio taping increased range of motion and agility during exercise in university students. Additional research on Kinesio taping for improving range of motion and agility is needed.

55Mn이 첨가된 SrTiO3 단 결정의 광 전이 특성연구 (Magneto-optical Properties of 55Mn-doped SrTiO3 Single Crystal)

  • 배규찬;박정일;이형락
    • 한국자기학회지
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    • 제21권6호
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    • pp.208-213
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    • 2011
  • Mori-Kawabata의 사영 연산자 방법을 $^{55}Mn$이 첨가된 $SrTiO^3$ 단 결정에 직접 적용하여, 이를 운동 방정식의 형태로 만드는 이론 체계를 사용하여 선모양 함수를 계산하였다. 외부 진동수 ${\nu}_0$ = 9.6 GHz에서 서로 다른 농도 [Mn] = 0.5 wt%와 2 wt%에 대한 온도 의존성으로 선폭을 조사하였다. 온도가 증가함에 따라 선폭은 감소하는 경향으로 확인되었고, 이는 선모양의 운동 좁아짐으로 보이며 고온영역 에서는 실험값과 비교적 일치함을 알 수 있었다. 이와 같이 계를 기술하는 스핀 해밀토니안에 연산자 방법을 이용한 선모양 함수는 실제 계의 적용에 편리한 급수전개로 하였으며, 다른 방법들에 비해 비교적 쉽게 계산할 수 있었다.

분노해결기법과 사례연구 - 세네카의 <분노에 대하여>를 바탕으로 - (Anger Resolution Techniques and Case Studies - Based on Seneca's De Ira -)

  • 손동선
    • 철학연구
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    • 제144권
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    • pp.205-234
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    • 2017
  • 세네카는 <분노에 대하여>를 통하여 세네카 특유의 분노의 특성과 분노의 예방 치유법을 제시했다. 이진남은 세네카의 분노 개념과 치유법에 존 듀이의 문제해결기법을 결합하여 다섯 단계의 분노해결기법을 고안했다. 그리고 이 기법으로 분노를 조절하고 제어하는 임상모델을 제시한다. 하지만 이진남의 시도는 분노를 제한적으로 다루고 있으며, 예방적 단기치료라는 한계점을 노정한다. 이를 보완하기 위하여 필자는 세네카가 구분한 분노 1,2단계는 통제 가능한 분노, 분노 3단계는 통제 불가능한 분노로 구분한다. 통제 불가능한 분노를 분노 자체인 분노와 분노로 인해서 유발된 문제를 함의하는 분노로 규정한다. 그리고 통제 불가능한 분노 중 분노 자체로서의 분노는 예방적 차원으로, 분노로 인해서 유발된 문제는 치유적 차원으로 접근할 필요가 있음을 제안한다. 이를 위하여 분노해결기법의 3단계인 '이해'의 단계를 수정하고 '도약' 이라는 6단계를 추가하여 기법을 보완한다. 이를 기반으로 통제 불가능한 분노에 노출된 내담자의 실제 사례를 임상모델로 제시하며 철학상담의 효과성과 정체성을 제시할 것이다.