• Title/Summary/Keyword: Closed-chain

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A Study on the Kinematic and Dynamic Analyses of Spatial Complex Kinematic Chain (공간 복합기구연쇄의 기구학 및 동역학 해석에 관한 연구)

  • 김창부;김효식
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.10
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    • pp.2543-2554
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    • 1993
  • In this paper, the kinematic and dynamic analyses of spatial complex kinematic chain are studied. Through the new method both using the set of identification numbers and applying the DenavitHartenberg link representation method to the spatial complex kinematic chain, the kinematic configuration of the chain is represented. Some link in the part of closed chain being fictitiously cutted, the complex kinematic chain is transformed to the branched chain. The kinematic constraint equations are derived from the constraint conditions which the cutted sections of the link have to satisfy. And the joint variables being partitioned in the independent joint variables and the dependent joint variables, the dependent variables are calculated from the independent variables by using the Newton-Raphson iterative method and the pseudoinverse matrix. The equations of motion are derived under the independent joint variables by using the principle of virtual work. Algorithms for dynamic analysis are presented and simulations are done to verify accuracy and efficiency of the algorithms.

Development of a New Robot Manipulator Driven by the Closed-chain Actuator (폐체인 구조의 새로운 다관절 로봇 매니퓰레이터 개발)

  • 최형식;백창열
    • Journal of Advanced Marine Engineering and Technology
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    • v.27 no.2
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    • pp.238-245
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    • 2003
  • To overcome the weakness in the load capacity of conventional robot manipulators actuated by motors with the speed reducer such as the harmonic driver, we proposed a new closed-chain type of the robot actuator which is composed of the four-bar-link mechanism driven by the ball screw. The robot manipulator is revolute-jointed and composed of four axes. The base axis is actuated by the lineal actuator such as the ball screw, and the others are actuated by the proposed actuator. We analyzed the mechanism of the actuators of the robot joints, and developed the dynamics model. The dynamics are expressed in the joint coordinates and then they are mapped into the sliding coordinates of the ball screw. We performed fundamental tests on the structure of the robot.

ASYMPTOTIC AVERAGE SHADOWING PROPERTY ON A CLOSED SET

  • Lee, Manseob;Park, Junmi
    • Journal of the Chungcheong Mathematical Society
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    • v.25 no.1
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    • pp.27-33
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    • 2012
  • Let $f$ be a difeomorphism of a closed $n$ -dimensional smooth manifold M, and $p$ be a hyperbolic periodic point of $f$. Let ${\Lambda}(p)$ be a closed set which containing $p$. In this paper, we show that (i) if $f$ has the asymptotic average shadowing property on ${\Lambda}(p)$, then ${\Lambda}(p)$ is the chain component which contains $p$. (ii) suppose $f$ has the asymptotic average shadowing property on ${\Lambda}(p)$. Then if $f|_{\Lambda(p)}$ has the $C^{1}$-stably shadowing property then it is hyperbolic.

Effect of Close kinetic chain and Open kinetic chain Position on Proprioceptive Neuromuscular Facilitation Applied to the Unilateral Upper Extremity on the Muscle Activation of Lower Extremity (닫힌사슬과 열린사슬 자세에서 편측상지에 적용된 PNF가 양측 하지의 근 활성도에 미치는 영향)

  • Han, Hyang-Wan;Kim, Sang-Soo
    • PNF and Movement
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    • v.7 no.3
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    • pp.17-27
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    • 2009
  • The purpose of this study was to investigate the effect of close kinetic chain(CKC) and open kinetic chain(OKC) posion on proprioceptive neuromuscular facilitation applied to the unilateral upper extremity on the muscle activation of lower extremity. All subjects were randomly assigned to two groups: open kinetic chain group(n=5),closed kinetic chain group(n=5). All participants were PNF patterns applied on the unilateral upper extremity in all subjects were the kinetic chain(CKC) and open kinetic chain(OKC) posion on flexion/abduction/external rotation. The hold and approximation techniques for the irradiation were applied to end range. All measurements for each subject took the following tests: pre-test, post - test in 4weeks, post-testin 8weeks. EMG data was collected from the vastus medialis, tibialis anterior, biceps femoris, and gastrocnemius muscle of both lower extreamity using surface EMG system, Each EMG value in individual muscle was normalized for maximal voluntary contraction. The data were analyzed using Two-way analysis of variance(ANOVA) with repeated measures to determine the statistical significances. The results of this study are summarized as follows. First, during for close kinetic chain(CKC) and open kinetic chain(OKC) posion on PNF pattern application, all of the %MVIC values of close kinetic chain and open kinetic chain posion increased sign ificantly compared(p<0.05). Second, The close kinetic chain(CKC) and open kinetic chain(OKC) posion on PNF pattern application was significantly increased with in the intervention period(p<.05). Third, there was a no significant open kinetic chain posion on PNF pattern application of sing muscle group with in the intervention period.(p<0.05) there was a significant close kinetic chain posion on PNF pattern application of sing muscle group with with in the intervention period(p<0.05). Forth, interaction of the exercise position and muscle was also significant. Post-hoc tests revealed that the activation levels of vastus medialis muscle and tibialis anterior muscle was higher in the closed kinetic chain position(p<.05). that the activation levels of vastus medialis and gastrocnemius muscle was higher in the open kinetic chain position(p<.05). In conclusion, it was found that the application of PNF patterns to the unilateral upper extremity effect on the muscle activation of lower extremity and both open kinetic chain exercise and closed kinetic chain exercise was significantly increased muscle activity. Further studies are needed to analyzed long term effects and subjects resulting from these changed.

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Effect of Forward-and-Backward Shift Trunk Exercise Using Proprioceptive Neuromuscular Facilitation Diagonal Pattern in Closed Kinematic Chain Exercises on Upper Limb Function and ADL in Stroke Patient -A Single-Subject Design- (닫힌사슬에서의 PNF 대각선 패턴을 이용한 몸통 전·후방 이동운동이 뇌졸중환자의 상지 기능 및 일상생활에 미치는 영향 -단일 사례 연구-)

  • Park, Si-Eun;Moon, Sang-Hyun
    • PNF and Movement
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    • v.15 no.3
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    • pp.237-246
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    • 2017
  • Purpose: The purpose of this study was to investigate the effects of forward-and-backward shift trunk exercise using a proprioceptive neuromuscular facilitation (PNF) diagonal pattern in a closed kinematic chain exercise on the upper limb function and activity of daily living (ADL) in a stroke patient. Methods: One subject participated in this study. The study used a reversal A-B-A' design, where A and A' were the baseline period (no intervention), and B was the intervention period. The intervention was a forward-and-backward trunk shift exercise, using a PNF diagonal pattern on both a stand-on-hand position and a quadruped position of closed kinematic chain exercises, for 20 min per day for 2 weeks. The range of motion (ROM) of the shoulder joint was measured and a Fugl-Meyer assessment of upper extremity (FMA-UE) and a functional independence measure (FIM) were performed to measure upper limb function and activity of daily living (ADL). Results: ROMs of shoulder joint (flexion, extension, abduction, and external rotation) increased in the intervention phase. The FMA-UE score increased (from 28 to 36) in the intervention phase. The FIM score increased (from 20 to 25) in the intervention phase. These increases were maintained after intervention (Baseline II). Conclusion: These results suggest that forward-and-backward shift trunk exercises using a PNF diagonal pattern in a closed kinematic chain exercise have a positive effect on stroke patients' upper limb function and ADL ability.

The Effects of PNF Arm Patterns on Activation of Leg Muscles According to Open And Closed Kinemetic Chains (열린사슬과 닫힌사슬에 따른 PNF상지패턴이 하지 근활성도에 미치는 영향)

  • Park, Tae-Jun;Park, Hyung-Ki;Kim, Jong-Man
    • Journal of the Korean Society of Physical Medicine
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    • v.6 no.2
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    • pp.215-223
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    • 2011
  • Purpose: The purpose of this study was to determine the effect of leg muscle activation by applying proprioceptive neuromuscular facilitation (PNF) arm patterns to unilateral upper extremities under the condition of both open and closed kinetic chains in a seated position. Methods: Twenty-two healthy subjects participated in this study. Four PNF patterns were applied to each subject's unilateral upper extremity. EMG data were collected from the vastus medialis, biceps femoris, tibialis anterior and gastrocnemius. The measured EMG data were digitized and processed to root mean square (RMS) and expressed as percentage maximal voluntary isometric contraction (%MVIC). The data were analyzed using two-way analysis of variance (ANOVA) with repeated measures to determine the statistical significance. Results: The results of this study were summarized as follows: Firstly, in comparison to muscle activation of the biceps femoris, there was a significant increase in the D2 flexion pattern when it was compared with D2 extension pattern and when it was compared with D1 flexion pattern (p<.05). Secondly, there was a significant increase in the muscle activation of the vastus medialis and tibialis anterior with a closed kinetic chain rather than an open kinetic chain (p<.05). Conclusion: In conclusion, in order to increase muscle activation of the biceps femoris, the D2 flexion pattern can be applied, regardless of kinetic chain. In addition, in order to increase muscle activation of the vastus medialis and tibialis anterior, four arm patterns can be applied with a closed kinetic chain.

Hybrid Genetic Algorithm Approach using Closed-Loop Supply Chain Model (폐쇄루프 공급망 모델을 이용한 혼합형유전알고리즘 접근법)

  • Yun, YoungSu;Anudari, Chuluunsukh;Chen, Xing
    • Journal of Korea Society of Industrial Information Systems
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    • v.21 no.4
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    • pp.31-41
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    • 2016
  • This paper is to evaluate the performance of a proposed hybrid genetic algorithm (pro-HGA) approach using closed-loop supply chain (CLSC) model. The proposed CLSC model is a integrated supply chain network model both with forward logistics and reverse logistics. In the proposed CLSC model, the reuse, resale and waste disposal using the returned products are taken into consideration. For implementing the proposed CLSC model, two conventional approaches and the pro-HGA are used in numerical experiment and their performances are compared with each other using various measures of performance. The experimental results show that the pro-HGA approach is more efficient in locating optimal solution than the other competing approaches.

The Effects of Closed Kinetic Chain Exercises on Thigh Circumference and Lysholm Scale of the Knee Joints of Patients with ACL Reconstruction (전방십자인대 재건술 후 닫힌사슬운동이 슬관절 대퇴둘레, Lysholm 척도에 미치는 영향)

  • Kim, Yeon-Ju;Lee, Yoon-Mi
    • The Journal of Korean Physical Therapy
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    • v.19 no.6
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    • pp.31-36
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    • 2007
  • Purpose: This study compared the thigh circumference and Lysholm scale of a stable and unstable exercise group of patients who had undergone an anterior cruciate ligament reconstruction (ACL reconstruction). Methods: The subjects were patients more than 4 weeks after their ACL reconstruction and could stand on one leg. The patients were divided into a control group with 9 patients performing closed kinetic chain exercises on a stable floor and an experimental group with 10 patients performing closed kinetic chain exercises en an unstable floor. The degree of muscle atrophy was compared by measuring the circumference of the injured thigh before the exercise program, and 3 weeks and 6 weeks after the exercise program. The Lysholm scale was used to assess the function of the knee joint. Results: There was no significant increase in thigh circumference according to the exercise periods in the two groups. However, there was a statistically significant increase before exercises and 6 weeks after the exercises (p<0.05). There were statistically significant differences in the Lysholm scores between the two groups (p<0.05). Conclusion: There were no statistically significant increase in the two groups, but there was a significant difference between before the exercise program and 6 weeks after the exercise program (p<0.05).

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The Effect of Static Balance Recovery by Open Kinetic Chain and Closed Kinetic Chain Exercises (열린 사슬 운동과 닫힌 사슬 운동이 정적균형 능력에 미치는 영향)

  • Kwon, Yoo-Jung;Bae, Sung-Soo;Park, Soo-Jin
    • Journal of the Korean Society of Physical Medicine
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    • v.4 no.1
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    • pp.23-30
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    • 2009
  • Purpose : This study was investigated the effect of static balance recovery during open kinetic chain exercise (OKC) and closed kinetic chain exercise(CKC). Methods : The paticipants were consisted of forty-one, was perform 3 sets, 3 times per week for 6 weeks, balance was measured by GOOD BALANCE. Statistical analysis was used repeated measure two-way ANOVA and independent t-test. Results : In CKC group, Center of presure(COP) medial-lateral(ML) velocity was significantly increased post 6 week test than pre-test, post 2 week test. COP anterior-posterior(AP) velocity was significantly increased post 6 week test than pre-test (p<.05). Conclusion : It was found that both OKC and CKC was significantly increased balance recovery in normal younng adults. In further study, it was suggested that was regard patient with muscle weakness.

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Status and Problems of Closed-Loop Supply Chain of Traditional Power Battery in China

  • Chen, Jinhui;Bayarsaikhan, Bayarsaikhan;Nam, Sootae;Jin, Chanyong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2021.10a
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    • pp.567-569
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    • 2021
  • The power battery supply chain in China currently lacks stable cooperation and effective information exchange. The competitive pressure brings about irregular recycling channels, reducing the operation and efficiency of the power battery supply chain. Besides, some regular power battery recycling enterprises fabricate data to obtain subsidies by taking advantage of the loopholes in the relevant policies of the state on recycling subsidies. Due to the high price of recycling in the black market, some regular enterprises resell the batteries recycled through regular channels, later purchasing the batteries with no utilization value to obtain the national recycling subsidies by cheating at the same time. Fig. 3 shows the present network structure of the tradi tional Chinese power battery closed-loop supply chain

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