Synthesis of Structure of Actuating Link Group with Common Drive Based on Formation and Analysis of Scheme of Functioning

Two analyses are presented for determining the drive shaft speed variations in a scotch yoke mechanism. The first analysis determines the speed variations when the mechanism is rigidly connected to a motor having a quadratic speed versus torque characteristic. The second analysis determines the speed variations when the mechanism is connected to a constant speed source through a flexible coupling. Together these models represent the two most common drive configurations. The results are of practical importance since they can be used in the preliminary calculations necessary in either the design of a main drive or the diagnosis of a drive problem in an existing machine. The methods are also of theoretical importance since they may be extended to the analysis of mechanisms having a greater harmonic content than the simple scotch yoke mechanism.

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On the Seifert fibered space link group

Topology and its Applications ◽

10.1016/j.topol.2016.03.020 ◽

2016 ◽

Vol 206 ◽

pp. 255-275 ◽

Cited By ~ 7

Author(s):

Boštjan Gabrovšek ◽

Enrico Manfredi

Keyword(s):

Link Group

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Errors in Force Generation and Changes in Controlling Patterns Following Agonist Muscle Fatigue

Journal of Applied Biomechanics ◽

10.1123/jab.25.4.293 ◽

2009 ◽

Vol 25 (4) ◽

pp. 293-303 ◽

Cited By ~ 4

Author(s):

Yi-Ming Huang ◽

Ya-Ju Chang ◽

Miao-Ju Hsu ◽

Chia-Ling Chen ◽

Chia-Ying Fang ◽

...

Keyword(s):

Muscle Fatigue ◽

Constant Error ◽

Antagonist Muscle ◽

Activation Level ◽

Before And After ◽

Agonist And Antagonist ◽

Common Drive ◽

The Common ◽

Possible Cause ◽

Related Increase

The purpose of this study was to evaluate whether agonist muscle fatigue changed the coactivation time and the co-contraction magnitude of the agonist and antagonist muscle, and if the agonist muscle fatigue produced bias (constant error: CE) and inconsistency (variable error: VE) of the force. Subjects are 10 healthy people and one person with impaired proprioception. EMG and force for fast (0.19 ± 0.06 s) and slow (1.20 ± 0.44 s) targeted isometric dorsiflexions were recorded before and after fatigue of the dorsiflexors. The results revealed that the coactivation time increased after fatigue only in the slow contractions but the co-contraction magnitude did not change. The postfatigue increment of the CE was greater in the fast contractions than in the slow ones. We conclude that the postfatigue compensatory strategy can reduce the fatigue-induced bias. The change of muscles activation level after fatigue might be under the influence of the common drive. Impaired proprioception is a possible cause of the fatigue-related increase in bias and inconsistency.

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Link State Protocol Data Mining for Shared Risk Link Group Detection

2010 Proceedings of 19th International Conference on Computer Communications and Networks ◽

10.1109/icccn.2010.5560151 ◽

2010 ◽

Cited By ~ 4

Author(s):

G. Das ◽

D. Papadimitriou ◽

W. Tavernier ◽

D. Colle ◽

T. Dhaene ◽

...

Keyword(s):

Data Mining ◽

Link State ◽

Link Group ◽

Group Detection ◽

Shared Risk

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Reorganization of multidigit physiological tremors after repetitive contractions of a single finger

Journal of Applied Physiology ◽

10.1152/japplphysiol.90851.2008 ◽

2009 ◽

Vol 106 (3) ◽

pp. 966-974 ◽

Cited By ~ 15

Author(s):

Ing-Shiou Hwang ◽

Zong-Ru Yang ◽

Chien-Ting Huang ◽

Mei-Chun Guo

Keyword(s):

Principal Component ◽

Motor Units ◽

Middle Finger ◽

Neuromuscular Function ◽

Transfer Effect ◽

Position Tracking ◽

Single Finger ◽

Common Drive ◽

Middle Ring ◽

Flexor Digitorum

In light of the interplay among physiological finger tremors, this study was undertaken to investigate the transfer effect of fatigue on coordinative strategies of multiple fingers. Fourteen volunteers performed prolonged position tracking with a loaded middle finger while measures of neuromuscular function, including electromyographic activities of the extensor digitorum (ED)/flexor digitorum superficialis (FDS) and physiological tremors of the index, middle, ring, and little fingers, were monitored. The subjects exhibited inferior tracking congruence and an increase in ED activity at the end of the tracking. Fatigue spread was manifested in a remarkable increase in tremor across fingers, in association with enhanced involuntary tremor coupling among fingers that was topologically organized in relation to the distance of the digits from the middle finger. Principal component analysis suggested that an enhanced 8- to 12-Hz central rhythm contributed primarily to the tremor restructure following fatigue spread. The observed tremor reorganization validated the hypothesis that the effect of fatigue was not limited to the instructed finger and that fatigue functionally decreased independence of the digits. The spreading of fatigue weakens neural inputs that diverge to motor units acting on various digits because of fatigue-related enhancement of common drive at the supraspinal level.

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Failure of normal development of central drive to ankle dorsiflexors relates to gait deficits in children with cerebral palsy

Journal of Neurophysiology ◽

10.1152/jn.00218.2012 ◽

2013 ◽

Vol 109 (3) ◽

pp. 625-639 ◽

Cited By ~ 28

Author(s):

Tue Hvass Petersen ◽

Simon F. Farmer ◽

Mette Kliim-Due ◽

Jens Bo Nielsen

Keyword(s):

Cerebral Palsy ◽

Frequency Domain ◽

Frequency Domain Analysis ◽

Response To Therapy ◽

Typically Developing ◽

Control Subjects ◽

Children With Cerebral Palsy ◽

Common Drive ◽

The Common ◽

Central Drive

Neurophysiological markers of the central control of gait in children with cerebral palsy (CP) are used to assess developmental response to therapy. We measured the central common drive to a leg muscle in children with CP. We recorded electromyograms (EMGs) from the tibialis anterior (TA) muscle of 40 children with hemiplegic CP and 42 typically developing age-matched controls during static dorsiflexion of the ankle and during the swing phase of treadmill walking. The common drive to TA motoneurons was identified through time- and frequency-domain cross-correlation methods. In control subjects, the common drive consists of frequencies between 1 and 60 Hz with peaks at beta (15–25 Hz) and gamma (30–45 Hz) frequencies known to be caused by activity within sensorimotor cortex networks: this drive to motoneurons strengthens during childhood. Similar to this drive in control subjects, this drive to the least affected TA in the CP children tended to strengthen with age, although compared with that in the control subjects, it was slightly weaker. For CP subjects of all ages, the most affected TA muscle common drive was markedly reduced compared with that of their least affected muscle as well as that of controls. These differences between the least and most affected TA muscles were unrelated to differences in the magnitude of EMG in the two muscles but positively correlated with ankle dorsiflexion velocity and joint angle during gait. Time- and frequency-domain analysis of ongoing EMG recruited during behaviorally relevant lower limb tasks provides a noninvasive and important measure of the central drive to motoneurons in subjects with CP.

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A family of two-generator non-Hopfian groups

International Journal of Algebra and Computation ◽

10.1142/s0218196717500321 ◽

2017 ◽

Vol 27 (06) ◽

pp. 655-675

Author(s):

Donghi Lee ◽

Makoto Sakuma

Keyword(s):

Continued Fraction ◽

Small Cancellation ◽

Continued Fraction Expansion ◽

Link Group

We construct [Formula: see text]-generator non-Hopfian groups [Formula: see text] where each [Formula: see text] has a specific presentation [Formula: see text] which satisfies small cancellation conditions [Formula: see text] and [Formula: see text]. Here, [Formula: see text] is the single relator of the upper presentation of the [Formula: see text]-bridge link group of slope [Formula: see text], where [Formula: see text] and [Formula: see text] in continued fraction expansion for every integer [Formula: see text].

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