• Title/Summary/Keyword: FORCE

Search Result 28,221, Processing Time 0.048 seconds

Online-Effects of Transcranial Direct Current Stimulation on Bimanual Force Control Performances in Healthy Young Adults (실시간 비침습적 뇌전기 자극이 양손 힘 조절능력에 미치는 영향)

  • Tae Lee, Lee;Joon Ho, Lee;Nyeonju, Kang
    • Korean Journal of Applied Biomechanics
    • /
    • v.32 no.4
    • /
    • pp.121-127
    • /
    • 2022
  • Objective: The purpose of this study was to investigate potential effects of transcranial direct current stimulation (tDCS) on bimanual force control capabilities in healthy young adults. Method: Eighteen right-handed healthy young adults (10 females and 8 males; age: 23.55 ± 3.56 yrs) participated in this crossover design study. All participants were randomly allocated to both active-tDCS and sham-tDCS conditions, respectively. While receiving 20 min of active- or sham-tDCS interventions, all participants performed bimanual isometric force control tasks at four submaximal targeted force levels (i.e., 5%, 10%, 15, and 20% of maximal voluntary contraction: MVC). To compare bimanual force control capabilities including force accuracy, variability, and regularity between active-tDCS and sham-tDCS conditions, we conducted two-way repeated measures ANOVAs (2 × 4; tDCS condition × Force levels). Results: We found no significant difference in baseline MVC between active-tDCS and sham-tDCS conditions. Moreover, our findings revealed that providing bilateral tDCS including anodal tDCS on left primary motor cortex (M1) and cathodal on right M1 while conducting bimanual force control trials significantly decreased force variability and regularity at 5%MVC. Conclusion: These findings suggest that providing bilateral tDCS on M1 areas may improve bimanual force control capabilities at a relatively low targeted force level.

Characteristic Comparison of Ground Reaction Force of the Taekwondo's Apkubi Motion and the Walking on Older Persons (고령자의 태권도 앞굽이서기 운동과 보행의 지면반력 특성비교)

  • Bae, Young-Sang;Kim, Ki-Man
    • Korean Journal of Applied Biomechanics
    • /
    • v.21 no.3
    • /
    • pp.289-296
    • /
    • 2011
  • The purpose of this study was to quantify the biomechanical characteristics of the ground reaction force(GRF) during the Taekwondo's Apkubi, one of the basic movement in Taekwondo and the walking. The GRF profiles under the stance foot of Apkubi movement and walking were directly measured in sample of 20 healthy older persons. In the anterior-posterior and vertical direction, the GRF of the Apkubi movement reached to the peak braking force at 10% of the normalized stance time percent and the peak driving force at 90% of stance time, but that of the walking reached to the peak braking force at 20% of stance time and the peak driving force at 80% of stance time. In vertical force, the GRF of the walking showed two peak values, but that of the Apkubi movement seemed three peak values. Moreover the first peak vertical force was significantly(t=6.085, p<.001) greater in the walking(about 1.8 times of body weight) than the Apkubi(about 1.4 times of body weight). The walking velocity was affected significantly(over p<.05) by the braking impulse, the peak braking force and the first peak vertical force. Futhermore the peak braking force in the Apkubi showed a significant effect on the Apkubi's stride length(p<.01). So, we concluded that the braking force after the right touch down, the stance foot on the ground contributed to move the leg forward.

A Study on "ICC Force Majeure Clause 2003" in International Sales Contract -Focused on comparison with the related provisions under CISG, PICC, PECL and the force majeure clause in Model International Sale Contract (ICC Force Majeure Clause 2003에 관한 연구 -계약관련 국제무역법규 및 ICC 국제모델매매계약상의 관련조항과의 비교를 중심으로-)

  • Huh, Jae-Chang
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.33
    • /
    • pp.221-243
    • /
    • 2007
  • A party to a contract is bound to perform its contractual duties. But outside events may make performance impossible, physically or legally. In such a situation a party may wish to plead "force majeure" as an excuse for failure to perform. The laws of most countries have provisions which dealt with force majeure. These provisions, however, vary from country to country and may not meet the parties' requirement in international contracts. Therefore, parties to international contracts are frequently in need of contract clauses on force majeure. There are many force majeure clauses in standard forms or individually negotiated. The ICC has drawn up provisions which aim at providing assistance for parties when they are making contracts. The force majeure clause grants relief from contractual sanctions and includes provisions for suspension and termination of contract. The purpose of this study is to examine "ICC Force Majeure Clause 2003" in the international sales contract. For this purpose, firstly this study deals with the major contents of the ICC Force Majeure Clause 1985 and 2003. Secondly this study considers the related provisions under CISG, PICC, PECL and the force majeure clause in Model International Sale Contract. Thirdly this study compares ICC Force Majeure Clause 2003 with the relative provisions under CISG, PICC, PECL and the force majeure clause in Model International Sale Contract. It should be noted that the parties often need to adapt the content of this clause so as to take account of the particular circumstances of the individual contract. This paper contributes to help the parties to a contract to draft the meaningful "Force Majeure Clause" containing more precise and elaborate provisions.

  • PDF

Correlations among Shearing Force, Morphological Characteristic, Chemical Composition, and In situ Digestibility of Alfalfa (Medicago sativa L) Stem

  • Liu, L.;Yang, Z.B.;Yang, W.R.;Jiang, S.Z.;Zhang, G.G.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.22 no.4
    • /
    • pp.520-527
    • /
    • 2009
  • Alfalfa (Medicago sativa L) is a high-quality forage for ruminants and the main stem is the dominant morphological component contributing to the forage nutritive value in mature alfalfa forage. Shearing force, a fracturing property of plant stem, is an important indictor of forage value. The objectives of this study were to investigate the effects of morphological characteristic on shearing force, the relationship between shearing force and chemical composition, and the relationship between shearing force and in situ digestibility of alfalfa stem. The results showed that linear density (weight per unit length of stem) was more important than chemical composition in affecting shearing force. There was a positive relationship between lignin content and shearing force (r = 0.78). Correlations were not found between shearing force and other chemical components such as neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose and hemicelluloses. In situ digestibility (of dry matter and NDF) was related to shearing force. A negative correlation was found between shearing force and dry matter (DM) digestibility (r = -0.70), and there was also a negative correlation between shearing force and NDF digestibility (r = -0.87). When shearing force was standardized for stem diameter or stem linear density, the relationship between shearing force and digestibility was consistent regardless of stem diameter and stem linear density. Shearing force was significantly correlated with lignin content and in situ digestibility (of DM and NDF), and was a more direct indicator for estimating forage nutritive value related to animal performance, so it can be used to predict the forage value of alfalfa.

밀링가공의 절삭조건 검증시스템 개발

  • 김찬봉;양민양
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1993.10a
    • /
    • pp.428-433
    • /
    • 1993
  • In this paper, the fast algorithm to calculate cutting force of milling and its application to NC verification system have been studied. The fast force algorithm can calculate the maximum cutting force fastly during one revelotion of tool. The NC verification using the fast force algorithm can verify excessive cutting force which is the cause of deflection and breakage of tool, and can so adjust the feed rate as to manufacture with the maximum force criterion or maximum machining error criterion. So, the fast force algorithm has been added to the NC verification system, the NC verification system can verify the physical problems in NC code effectively.

  • PDF

A Permanent-Magnet Linear Motor Shape Optimal Design Using Coupling Particles Swarm Optimization

  • Baatar, Nyambayar;Pham, Minh-Trien;Koh, Chang-Seop
    • Proceedings of the KIEE Conference
    • /
    • 2009.07a
    • /
    • pp.788_789
    • /
    • 2009
  • The cogging force of a permanent-magnet linear motor is a major component of the detent force, but unfortunately makes a ripple in the thrust force and induces undesired vibration and acoustic noise. In this paper, Coupling Particles Swarm Optimization is applied to optimization the shape of permanent magnet linear motor by minimizing the undesired vibration and acoustic noise in the thrust force and also considering the maximum thrust force. The result shows that the 9-pole 10-slot PMLM removes almost of the cogging force while giving a big thrust force.

  • PDF

Force-finding of Tensegrity Structure using Optimization Technique

  • Lee, Sang Jin
    • Architectural research
    • /
    • v.17 no.1
    • /
    • pp.31-40
    • /
    • 2015
  • A simple force-finding process based on an optimization technique is proposed for tensegrity structures. For this purpose, the inverse problem of form-finding process is formulated. Therefore, the position vector of nodes and element connectivity information are provided as priori. Several benchmark tests are carried out to demonstrate the performance of the present force-finding process. In particular, the force density distributions of simplex tensegrity are thoroughly investigated with the important parameters such as the radius, height and twisting angle of simplex tensegrity. Finally, the force density distribution of arch tensegrity is produced by using the present force-finding process for a future reference solution.