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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

IMPULSIVE VIBRATION AND EXPOSURE LIMIT

SVOBODA, LADISLAV, SMOLÍKOVÁ, LIBUŠE, MUFF, VLADIMIL, HARTLOVÁ, DARINA, LOUDA, LADISLAV 05 1900 (has links)
No description available.
92

Theoretical framework for the study of sensory-motor integration /

Torres, Elizabeth B. January 2001 (has links)
Thesis (Ph. D.)--University of California, San Diego, 2001. / Vita. Includes bibliographical references (leaves 115-120).
93

Frazeologizmų su leksemomis ranka ir koja semantinė motyvacija / Semantic motivation of phraseologisms with words arm and leg

Paunksnytė, Svetlana 16 August 2007 (has links)
Darbo objektas – lietuvių kalbos frazeologizmai su leksemomis ranka ir koja. Svarbiausias darbo tikslas – aptarti frazeologizmų su leksemomis ranka ir koja semantinę motyvaciją remiantis kognityvinės kalbotyros principais.Darbą sudaro pratarmė, įvadas, svarbiausia darbo dalis, išvados, literatūros sąrašas, priedas. Įvadinėje darbo dalyje trumpai aptariama frazeologizmo samprata bei variantai, sinonimai ir antonimai, apžvelgiami lietuvių frazeologizmų tyrimai, apibūdinama koncepto ir konceptualiosios metaforos samprata. Pagrindinę darbo dalį sudaro du skyriai, kur aptariami leksemų ranka ir koja motyvuojami frazeologizmai, jų sąsajos su skirtingomis žmonių veiklos sferomis. Tyrimo rezultatai apibendrinami išvadose. Darbe pateikiami 2 paveikslai. Šaltinių sąrašą sudaro 7, literatūros sąrašą – 28 pozicijos. Pateikiamas trumpas konceptualiųjų metaforų su leksemomis ranka ir koja žodynėlis. / Object of the paper is phraseological units of the Lithuanian language with lexemes “arm” and “leg”. The main objective of the paper is to discuss the semantic motivation of phraseological units with lexemes “arm” and “leg” following the principles of cognitive linguistics. The paper comprises a preface, introduction, the main chapter, conclusions, list of references, and annex. In the introductory chapter, the conception of a phraseological unit is discussed along with variables, synonyms and antonyms, research on the Lithuanian phraseological units is overviewed, and the conception of a concept and conceptual metaphor is described. The main chapter consists of two sections, in which phraseological units motivated with lexemes “arm” and “leg” are discussed along with their links to people’s separate activity fields. The research results are summarised in conclusions. 2 pictures are provided in the paper. The list of sources comprises 7 and the list of references 28 positions. A brief vocabulary of conceptual metaphors with lexemes “arm” and “leg” is provided.
94

A push strength prediction model for the shoulder height transverse plane

Underwood, Ralph Conway 08 1900 (has links)
No description available.
95

A mathematical predictive model of arm strength

Lower, Robert Spencer 08 1900 (has links)
No description available.
96

An investigation into the pathophysiology of non-specific arm pain: an examination of the utility and reliability of quantitative electomyography

Calder, KRISTINA 18 November 2009 (has links)
The wrist extensor muscles have been implicated in a work-related upper limb disorder referred to as non-specific arm pain (NSAP), which has an unknown pathophysiology. The primary objective of this thesis was to perform an electrophysiological evaluation of NSAP to gain a better understanding of the underlying pathophysiology. Secondary objectives were to determine the utility and reliability of the decomposition-based quantitative electromyography (DQEMG) system used to examine NSAP. The utility of the DQEMG system was first tested to determine whether physiological changes in muscles of healthy individuals performing low-level fatiguing contractions could be detected using this approach. Next, the reliability of the outcome variables produced through this system was tested on healthy individuals performing low-level non-fatiguing contractions. A case-control study was then performed using DQEMG to determine whether there were measurable changes in electrophysiological variables that suggest whether NSAP is myopathic or neuropathic in nature. Finally, the case control study was repeated using a less invasive approach of electrophysiological evaluation to determine if this method might be equally useful in determining the pathophysiology of NSAP. Results revealed DQEMG can be effectively and reliably used to detect changes in the physiological characteristics of motor units that accompany fatigue. Specifically, decreases in mean motor unit firing rates along with increases in amplitude, duration, and area parameters of needle- and surface-detected motor unit potentials (MUPs) suggest that recruitment is a main cause of increased electromyographic amplitude parameters with fatigue. Results of the reliability study suggested that DQEMG provides sufficiently consistent results to allow it to be effectively used for quantitative electromyographic (QEMG) analysis. In the first case control study, the QEMG parameters suggested that the underlying pathophysiology in NSAP may be myopathic in nature; specifically, QEMG findings for the NSAP group revealed smaller MUPs compared to the other groups. Lastly, the case control study using spike shape analysis across different levels of isometric wrist extension contractions was deemed to be useful in determining differences among the groups. This research suggests that NSAP may be myopathic in nature, since the NSAP group showed significantly lower mean spike amplitude and mean spike slope values compared to healthy subjects. / Thesis (Ph.D, Rehabilitation Science) -- Queen's University, 2008-08-27 14:53:55.892
97

ROTATION ENCODING OF C-ARM FLUOROSCOPES WITH ACCELEROMETER

GRZEDA, VICTOR 28 January 2011 (has links)
Accurate, practical, and affordable pose tracking on manually operated C-arm fluoroscopes is a major technical challenge. Conventional tracking methods, such as optical cameras and radiographic fiducials, are hampered by significant shortcomings. Optical cameras are delicate, costly, and have a complex system setup that is easily susceptible to camera obstruction in cluttered operating room. Radiographic fiducials occupy a significant portion of the fluoroscopic imaging space. Using fiducials also requires segmentation that limits clinical use. In this thesis, an alternative form of tracking is proposed to encode the rotational joints of manually operated C-arms using a tilt sensing accelerometer for tracking the C-arm rotational pose. The technique is evaluated by affixing an accelerometer to a full-scale C-arm where a webcam is used as a substitute for X-ray imaging. Ground truth C-arm rotational poses were obtained from the webcam by tracking a checkerboard plate. From these rotational poses, a series of angle and structural correction equations were formulated that can properly relate the accelerometer angle readings to the C-arm rotational pose in real-time and compensate for systematic structural C-arm deformations, such as sagging and bending. Real-time rotational pose tracking of the primary and secondary joint rotations of the C-arm showed an accuracy of 0.5 degrees in the entire range of interest. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2011-01-28 12:07:32.781
98

Learning and retention adaptations of myoelectric activity during a novel multi-joint task

Sarantinos, George D. V. January 1999 (has links)
The learning and retention adaptations of muscle activity were studied during a novel multi-joint task. Electromyographic (EMG) signals were recorded from the posterior deltoid, long and lateral heads of the triceps, pectoralis major, biceps and brachioradialis muscles. These data were assayed in a pattern recognition analysis (SVD) to ascertain the minimum number of 'common features' or waveforms (W's) required to describe the set of input EMG patterns (IP). / Fifteen participants performed targeted arm movements, which incorporated the shoulder and elbow articulations, as fast and as accurately as possible in the horizontal plane. Both experimental (E) and control (C) groups were employed. The E group was trained (Day 1 to Day 4) and tested both pre- and post-learning. They were further re-tested during a retention period (RET) consisting of 1, 2, 4, 6 and 8 week post-learning sessions. The C group was tested before and after learning and at the end of the RET period. (Abstract shortened by UMI.)
99

Learning adaptations in performance production measures of novel multijoint tasks

Vardaxis, Vassilios January 1995 (has links)
The present thesis investigated the process of gross motor skill acquisition in the context of how movement pattern characteristics are organized and modified as a result of learning. The process of multisegmental skill acquisition was studied using performance production measures as a window to explore stable and transient changes in the movement control process. Bernstein's principles of exploitation of motion dependent torques, and the minimization of the degree of freedom were tested. / Twenty male subjects performed a total of 240 trials, as fast and accurate as possible, over 4 sessions for two tasks with different level of complexity (10 subjects per task). Kinematic and EMG data were acquired for a two segment model of the arm using a lightweight, adjustable manipulandum, and surface EMG for the PDL, PEC, TRI, and BIC muscles. Movement organization characteristics were revealed by wave pattern analyses performed with a phase breakdown technique, CCCF on torque partitioning components, and the CFs on the muscle activation waveforms. / The experimental protocol allowed enough practice for the tasks to be learned resulting in PT decrease. Consistent adaptations in movement organization were revealed by all three levels of analysis. Improvement in the performance production measures were in the same direction for both learning conditions, and the rate of change within experimental sessions decreased over time. The significant adaptations in movement organization occurred at the critical phases of each task (i.e. the power absorption--phase simple task, and the reversal phase--complex task). The EMG and joint torque components demonstrated significant amplitude and profile changes particularly during the critical phases. The subjects learned to perform the tasks faster by compensating the motion dependent torques components with the muscle torques in time and amplitude. This finding was consistent with the principle of exploitation of motion dependent torques which was enhanced with learning. Significant task specific motor program adaptations were revealed by the SVD analysis. The minimization of the degree of freedom hypothesis is consistent with the increasing covariation observed over learning between the antagonists PEC and BIC in the simple task, and for both the agonists PDL and TRI and antagonists PEC and BIC in the complex task. In addition the results justified the use of waveform analysis on performance production measures, as a method that can reveal important adaptation details in the underlying control mechanisms for gross motor skill.
100

Rhythmic arm cycling differentially modulates stretch and H-reflex amplitudes in soleus muscle

Palomino, Andres Felipe 08 July 2011 (has links)
During rhythmic arm cycling soleus H-reflex amplitudes are reduced by modulation of group Ia presynaptic inhibition (Frigon et al, 2004). This reflex suppression is graded with the frequency of arm cycling (Loadman & Zehr 2007; Hundza & Zehr 2009) and 0.8 Hz is the minimum frequency to significantly reduce the soleus H-reflex (Hundza & Zehr 2009). Despite the data on modulation of the soleus H-reflex amplitude induced by rhythmic arm cycling, comparatively little is known about the modulation of stretch reflexes due to remote limb movement. Therefore, the present study was intended to explore the effect of arm cycling on stretch and H-reflex amplitudes in the soleus muscle. In so doing, additional information on the mechanism of action during rhythmic arm cycling would be revealed. Although both reflexes share the same afferent pathway, we hypothesized that stretch reflex amplitudes would be less suppressed by arm cycling because they are less inhibited by presynaptic inhibition (Morita et al, 1998). Failure to reject this hypothesis would add additional strength to the argument that Ia presynaptic inhibition is the mechanism modulating soleus H-reflex amplitude during rhythmic arm cycling. Participants were seated in a customized chair with feet strapped to footplates. Three motor tasks were performed: static control trials and arm cycling at 1 and 2 Hz. Soleus H-reflexes were evoked using single 1 ms pulses of electrical stimulation delivered to the tibial nerve at the popliteal fossa. A constant M-wave and ~6% MVC activation of soleus was maintained across conditions. Stretch reflexes were evoked using a vibratory shaker (ET-126; Labworks Inc). The shaker was placed over the triceps surae tendon and controlled by a custom written LabView program (single sinusoidal pulse at 100Hz). Results demonstrated that rhythmic arm cycling that was effective for conditioning soleus H-reflexes did not show a suppressive effect on the amplitude of the soleus stretch reflex. We suggest this indicates that stretch reflexes are less sensitive to conditioning by rhythmic arm movement, as compared to H-reflexes, due to the relative insensitivity of Ia presynaptic inhibition. / Graduate

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