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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.
271

Σχεδίαση κατασκευή και υλοποίηση σύγχρονου μικροϋπολογιστικού συστήματος

Βουγιούκας, Ηλίας 13 October 2013 (has links)
Η εργασία αυτή ερευνά την σχεδίαση ενός σύγχρονου μικροϋπολογιστικού συστήματος βασισμένο σε επεξεργαστή ARM COrtex-M3. Στα πλαίσια αυτής της σχεδίασης έγινε μελέτη των συσκευών που είναι απαραίτητες για την λειτουργία ενός παλμογράφου, και σχεδιάστηκε λογισμικό προσέγγισης της λειτουργίας των βασικών περιφερειακών του. Επιπλέον, γίνεται μια ανάλυση ενός συστήματος απεικόνισης γραφικών, χωρίς την χρήση του μικροελεγκτή, και ποιοτικός σχεδιασμός του συστήματος αυτού. Τέλος, εξάγονται συμπεράσματα για πολυπλοκότητα του σχεδίου και σχολιάζονται οι συμβιβασμοί που είναι απαραίτητοι για την υλοποίηση ενός συστήματος πραγματικού χρόνου. / This thesis analyzes the design of a modern microprocessing system based on an ARM Cortex-M3 microcontroller. For the implemantation of the design thorough research on the necessary peripherals of an oscilloscope is presented and several applications simulating the behavior of its basic functions via its peripherals. Furthermore, a qualitative design is created on a potential graphical processing system, able to fulfill all of the tasks needed to depict on-screen, without burdening the central processor. Conclusions are drawn on the complexity of the design and the tradeoffs of designing a realtime system.
272

Clinical and kinematic assessments of upper limb function in persons with post-stroke symptoms

Johansson, Gudrun M January 2015 (has links)
Stroke is a common and multifaceted disease that often involves motor deficits in the upper limb. This thesis investigated reliability and validity of existing clinical assessments of upper limb function in persons with post-stroke symptoms and in non-disabled controls. Study I was conducted in a clinical setting where the Motor Evaluation Scale of Upper Extremity in Stroke patients (MESUPES) was assessed in persons post-stroke by two physiotherapists selected from a group of four.  Study II-IV took place in a motion analysis laboratory with an optoelectronic system. Kinematic measures and clinical measures were used to investigate the validity of the Arm Posture Score (APS), the Finger-to-Nose test (FNT), and the Standardised Nine Hole Peg test (S-NHPT) in persons post-stroke and non-disabled controls.   The results showed that the MESUPES had a high inter-rater reliability while the concurrent validity was not fully confirmed. MESUPES has a maximum score of 58 and the minimal detectable change ranged from 5 to 8 for a confidence level of 80% and 95%. The Arm Posture Scores, which include either four or six arm movement variables, were able to distinguish between the affected and non-affected arms, as well as between the affected arm and the non-dominant arm of the controls. The total movement time of the FNT, which is a coordination test, was able to distinguish persons post-stroke from controls, at least at a group level. Movement smoothness, accuracy and compensation, obtained from kinematic analysis, were the most discriminative variables for the FNT. Smoothness was most strongly correlated with the timed FNT and had the greatest association with the variance of the timed FNT. For the S-NHPT, which is a dexterity test involving grasping and reaching, the movement times, smoothness and compensation discriminated between the stroke group and the control group. Persons post-stroke spent considerably more time in the grasp-related parts of the task compared to controls. Smoothness and upper limb impairments had the strongest correlation with the S-NHPT.   In conclusion, the clinical measures used within stroke rehabilitation seem valid and reliable, although some limitations are highlighted by the kinematic assessment. MESUPES was shown to be a reliable assessment of upper limb movement quality after stroke. The kinematic analysis revealed that the timed FNT does not have sufficient discriminative validity at an individual level. The timed FNT reflected speed-related aspects of pointing movements such as smoothness and length of the deceleration phase, but should not be used as an overall measure of upper limb coordination after stroke. The timed S-NHPT demonstrated sufficient discriminative validity and reflected smoothness and upper limb impairments. For both the FNT and S-NHPT, kinematic analysis showed that the clinical outcomes of those tests (time of performance) did not adequately detect qualitative aspects of the upper limb movements after stroke such as possible compensatory movements. Therefore, clinical assessments that capture qualitative aspects of upper limb movements would improve the assessment of upper limb coordination and dexterity after stroke. In addition, 3D movement analysis provided unique information about upper limb function after stroke, not least in persons with mild post-stroke impairments. The APS, for instance, which quantifies how much the arm swing during gait deviates from normal, discriminated between persons with stroke and non-disabled persons. Such subtle deviations are not possible to quantify with the human eye.
273

Perceived exertion relationships and prediction of peak oxygen uptake in able-bodied and paraplegic individuals

Al-Rahamneh, Harran Qoblan Mefleh January 2010 (has links)
Rating of Perceived Exertion (RPE) relates to how ‘hard’ or ‘easy’ an exercise feels. The Borg 6-20 RPE scale is the most widely used scale to estimate the overall, peripheral and central perception of effort. To date, there are a limited number of studies on the use and efficacy of perceived exertion in persons with spinal cord injury and/or disease. The findings from these studies are also equivocal. Therefore, the aims of this thesis were to assess: i) the relationship between the RPE and physical and physiological markers of exercise intensity during arm cranking exercise in able-bodied and individuals with spinal cord disease, ii) the efficacy of sub-maximal RPE values to predict peak oxygen uptake during arm cranking exercise in able-bodied and paraplegic individuals using different exercise protocols, iii) the scalar property of the RPE during arm cranking exercise in able-bodied and paraplegic individuals. To achieve these goals, the thesis has been broken down to a series of seven studies. In each of these studies, except study 6, a group of able-bodied and a group of paraplegic participants were recruited to asses these hypotheses. Paraplegic individuals had spinal cord injury with neurological levels at or below the sixth thoracic vertebra (T6) or flaccid paralysis as a result of poliomyelitis infection. These individuals were physically active and participated in sports like wheelchair basketball, weightlifting, wheelchair racing and table tennis at both professional and recreational levels. Able-bodied participants were healthy and free from pre-existing injuries and physically active but not arm-trained. There were strong relationships between the RPE and each of the physiological and physical indices of exercise intensity during arm cranking exercise regardless of group or gender. Peak oxygen uptake can be predicted with reasonable accuracy from sub-maximal oxygen uptake values elicited during a sub-maximal perceptually-guided, graded exercise test for paraplegic individuals but not for able-bodied participants. It has also been shown that peak oxygen uptake can be predicted from power output using the equation prescribed by the American College of Sports Medicine (ACSM, 2006). Furthermore, for able-bodied participants using estimation procedures, a passive process in which an individual is asked to rate how ‘hard’ or ‘easy’ an exercise feels, the ramp exercise test provided more accurate prediction of peak oxygen uptake compared to the graded exercise test. For paraplegic persons using estimation procedures, the graded exercise test provided more accurate prediction of peak oxygen uptake compared to the ramp exercise test. Finally, the scalar property of the RPE (i.e., similar proportions of time at a given RPE) was evident during arm cranking exercise regardless of group. In conclusion, the prediction of peak oxygen uptake from sub-maximal exercise tests would provide a safer environment of exercise testing. In addition, using a sub-maximal protocol would make peak oxygen uptake more available for sedentary and clinical population compared to the graded exercise test to volitional exhaustion. Prediction of peak oxygen uptake from power output using the ACSM equation would make the estimation of peak oxygen uptake more available for large groups of people. Similar proportions of time were observed at a given RPE regardless of group or exercise intensity. The early RPE responses will give an indicator for how long a participant is going to exercise. This has important implications for rehabilitation settings. Based on the RPE responses the tester or the observer can increase or decrease the work rate to enable the participant to exercise for the desired duration.
274

The accuracy and precision of kinesiology-style manual muscle testing : designing and implementing a series of diagnostic test accuracy studies

Jensen, Anne January 2014 (has links)
<b>Introduction</b>: Kinesiology-style manual muscle testing (kMMT) is a non-invasive assessment method used by various types of practitioners to detect a wide range of target conditions. It is distinctly different from the muscle testing performed in orthopaedic/neurological settings and from Applied kinesiology. Despite being estimated to be used by over 1 million people worldwide, the usefulness of kMMT has not yet been established. The aim of this thesis was to assess the validity of kMMT by examining its accuracy and precision. <b>Methods</b>: A series of 5 diagnostic test accuracy studies were undertaken. In the first study, the index test was kMMT, and the target condition was deceit in verbal statements spoken by Test Patients (TPs). The comparator reference standard was a true gold standard: the actual verity of the spoken statement. The outcomes of the muscle tests were interpreted consistently: a weak result indicated a Lie and a strong result indicated a Truth. A secondary index test was included as a comparator: Intuition, where Practitioners used intuition (without using kMMT) to ascertain if a Lie or Truth was spoken. Forty-eight Practitioners were recruited and paired with 48 unique kMMT-naïve TPs. Each Pair performed 60 kMMTs broken up into 6 blocks of 10, which alternated with blocks of 10 Intuitions. For each Pair, an overall percent correct was calculated for both kMMT and Intuition, and their means were compared. Also calculated for both tests were sensitivity, specificity, positive predictive value and negative predictive value. The second study was a replication of the first, using a sample size of 20 Pairs and a less complex procedure. In the third study, grip strength dynamometry replaced kMMT as the primary index test. In the fourth study, the reproducibility and repeatability of kMMT were examined. In the final study, TPs were presented with emotionally-arousing stimuli in addition to the affect-neutral stimuli used in previous studies, to assess if stimuli valence impacted kMMT accuracy. <b>Results</b>: Throughout this series of studies, mean kMMT accuracies (95% Confidence Intervals; CIs) ranged from 0.594 (0.541 – 0.647) to 0.659 (0.623 - 0.695) and mean Intuition accuracies, from 0.481 (0.456 - 0.506) to 0.526 (0.488 - 0.564). In all studies, mean kMMT accuracies were found to be significantly different from mean Intuition accuracies (p ≤ 0.01), and from Chance (p < 0.01). On the other hand, no difference was found between grip strength following False statements compared to grip strength following True statements (p = 0.61). In addition, the Practitioner-TP complex accounted for 57% of the variation in kMMT accuracy, with 43% unaccounted for. Also, there was no difference in the mean kMMT accuracy when using emotionally-arousing stimuli compared to when using affect-neutral stimuli (p = 0.35). Mean sensitivities (95% CI) ranged from 0.503 (0.421 - 0.584) to 0.659 (0.612 - 0.706) while mean specificities (95% CI) ranged from 0.638 (0.430 - 0.486) to 0.685 (0.616 - 0.754). Finally, while a number of participant characteristic seemed to influence kMMT accuracy during one study or another, no one specific characteristic was found to influence kMMT accuracy consistently (i.e. across the series of studies). <b>Discussion</b>: This series of studies has shown that kMMT can be investigated using rigorous evidence-based health care methods. Furthermore, for distinguishing lies from truths, kMMT has repeatedly been found to be significantly more accurate than both Intuition and Chance. Practitioners appear to be an integral part of the kMMT dynamic because when replaced by a mechanical device (i.e. a grip strength dynamometer), distinguishing Lies from Truth was not possible. In addition, since specificities seemed to be greater than sensitivities, Truths may have been easier to detect than Lies. A limitation of this series of studies is that I have a potential conflict of interest, in that I am a practitioner of kMMT who gets paid to perform kMMT. Another limitation is these results are not generalisable to other applications of kMMT, such as its use in other paradigms or using muscles other than the deltoid. Also, these results suggest that kMMT may be about 60&percnt; accurate, which is statistically different from Intuition and Chance; however it has not been established if 60&percnt; correct is "good enough" in a clinical context. As such, further research is needed to assess its clinical utility, such as randomised controlled trials investigating the effectiveness of whole kMMT technique systems. Also, future investigators may want to explore what factors, such as specific Practitioner and TP characteristics, influence kMMT accuracy, and to investigate the validity of using kMMT to detect other target conditions, using other reference standards and muscles other than the deltoid. <b>Summary</b>: This series of diagnostic test accuracy studies has found that kMMT can be investigated using rigorous methods, and that kMMT used to distinguish Lies from Truths is significantly more accurate that both Intuition and Chance. Further research is needed to assess kMMT’s clinical utility.
275

A Mechanical Analysis of Suspensory Locomotion in Primates and Other Mammals

Granatosky, Michael Constantine January 2016 (has links)
<p>For primates, and other arboreal mammals, adopting suspensory locomotion represents one of the strategies an animal can use to prevent toppling off a thin support during arboreal movement and foraging. While numerous studies have reported the incidence of suspensory locomotion in a broad phylogenetic sample of mammals, little research has explored what mechanical transitions must occur in order for an animal to successfully adopt suspensory locomotion. Additionally, many primate species are capable of adopting a highly specialized form of suspensory locomotion referred to as arm-swinging, but few scenarios have been posited to explain how arm-swinging initially evolved. This study takes a comparative experimental approach to explore the mechanics of below branch quadrupedal locomotion in primates and other mammals to determine whether above and below branch quadrupedal locomotion represent neuromuscular mirrors of each other, and whether the patterns below branch quadrupedal locomotion are similar across taxa. Also, this study explores whether the nature of the flexible coupling between the forelimb and hindlimb observed in primates is a uniquely primate feature, and investigates the possibility that this mechanism could be responsible for the evolution of arm-swinging. </p><p> To address these research goals, kinetic, kinematic, and spatiotemporal gait variables were collected from five species of primate (Cebus capucinus, Daubentonia madagascariensis, Lemur catta, Propithecus coquereli, and Varecia variegata) walking quadrupedally above and below branches. Data from these primate species were compared to data collected from three species of non-primate mammals (Choloepus didactylus, Pteropus vampyrus, and Desmodus rotundus) and to three species of arm-swinging primate (Hylobates moloch, Ateles fusciceps, and Pygathrix nemaeus) to determine how varying forms of suspensory locomotion relate to each other and across taxa. </p><p> From the data collected in this study it is evident the specialized gait characteristics present during above branch quadrupedal locomotion in primates are not observed when walking below branches. Instead, gait mechanics closely replicate the characteristic walking patterns of non-primate mammals, with the exception that primates demonstrate an altered limb loading pattern during below branch quadrupedal locomotion, in which the forelimb becomes the primary propulsive and weight-bearing limb; a pattern similar to what is observed during arm-swinging. It is likely that below branch quadrupedal locomotion represents a “mechanical release” from the challenges of moving on top of thin arboreal supports. Additionally, it is possible, that arm-swinging could have evolved from an anatomically-generalized arboreal primate that began to forage and locomote below branches. During these suspensory bouts, weight would have been shifted away from the hindlimbs towards forelimbs, and as the frequency of these boats increased the reliance of the forelimb as the sole form of weight support would have also increased. This form of functional decoupling may have released the hindlimbs from their weight-bearing role during suspensory locomotion, and eventually arm-swinging would have replaced below branch quadrupedal locomotion as the primary mode of suspensory locomotion observed in some primate species. This study provides the first experimental evidence supporting the hypothetical link between below branch quadrupedal locomotion and arm-swinging in primates.</p> / Dissertation
276

Development of a computerized assessment tool for hand-arm function after stroke- test-retest reliability and convergent validity

Imran, Zoya 15 September 2016 (has links)
Many performance-based assessment tools are available to measure upper extremity function. Most define hand function by the time taken to complete a task. A new computer game-based hand-arm function evaluation (GHA) tool has been developed to quantify fine and gross object manipulations skills. Objective of this study was to evaluate the test-retest reliability and convergent validity of the GHA assessment tool. Thirty stroke clients with the mean age of 68.41 years were recruited. Test-retest reliability was assessed by Intraclass correlation coefficient (ICCs) and t-test. Convergent validity between GHA and the Wolf Motor Function Test (WMFT) was determined using the Pearson’s correlation coefficient. Most of the GHA outcome measures had moderate to high ICC (0.5-0.9). With scant exceptions, low correlations were observed between GHA measures and WMFT score. The ICC values reflected the complexity of the tasks, more complex task showed lower ICCs values. / October 2016
277

Joint Center Movement Analysis and 3D Motion Modeling of Upper Arm - Comparison of Several Algorithms with the Visual 3-D Program

Joseph, Leena 01 January 2005 (has links)
600 out of every 100,000 people in the United States today suffer from some form of cerebellar disease that causes major abnormalities in the equilibrium and aligned, coordinated movement of the body. Hence it becomes essential to diagnose the extent of the movement and gait disorder and provide required therapy to the patients. Various developments have been made in the designing and application of interactive software system for body positioning. Object oriented design techniques are used in the field of software engineering for interactive geometric representation of system behavior. Motion analysis of the upper and lower extremities of the body could be beneficial in the diagnosis and therapy of numerous orthopedic and neurological ailments. Mathematical models of neuro-musculoskeletal dynamics establish a scientific basis for movement analysis. As mentioned above, an interactive geometric representation of the system behavior is an important diagnostic tool in orthopedic therapy. This realistic depiction of the human body with respect to the model is a very effective diagnostic tool for clinicians. There are existing biomechanical modeling tools like Visual 3-D etc, that are used for motion analysis. Visual 3-D was developed by the movement disorders laboratory at NIH. The preferred method is to place markers on the segments and calculate the joint center locations using a rigid-body assumption. However studies have shown that markers on the joint centers are subject to artifact (skin movement). Moreover, very few details are provided on the algorithm used by Visual 3-D, and no "fixes" are provided for marker dropout. This project aims at testing the accuracy of existing biomechanical movement analysis software Visual 3D by calculating the rigid body motion from the spatial co-ordinates of the markers clusters on the subject's upper extremities. This project tries to emulate their approach in a simple and effective manner and at the same time validate the approach by testing it by three different methods by calculating the elbow and wrist locations during a forward reaching motion of the subject. A mathematical model is developed by determining a relationship between the projections of a particular point in two different planes or on a single plane in two different directions [Kinzel, G.L. et. al. 1972]. The computer simulations are performed using MATLAB to calculate the lunematical parameters from the co-ordinates of projections of markers placed on the upper extremities of the subject's body. This relation will aid in quantitative motion analysis of the upper extremities in the rehabilitation setting. This can be extended to in-depth gait analysis of the lower extremities too. This type of biomechanical movement analysis allows us to understand the dynamic implications of a particular impairment, such as spasticity or weakness, in a particular muscle group.
278

Evaluation of power management strategies on actual multiprocessor platforms / Évaluation de stratégies de gestion de la consommation pour des plateformes multiprocesseurs concrètes

Khan Jadoon, Jabran 25 March 2013 (has links)
L’objectif de cette thèse est d’étudier l’efficacité énergétique des stratégies basse consommation pour des plateformes représentatives. Principalement, nous nous intéresserons aux stratégies énergétiques pour des systèmes embarqués multicœur en étudiant le comportement de politiques logicielles qui permettent la réduction effective de l’énergie tout en répondant aux exigences applicatives. Le travail présenté dans ce mémoire vise à étudier des stratégies de gestion de la consommation pour des plateformes monoprocesseur puis multiprocesseur concrètes. L’approche utilisée pour cette étude fut basée sur des plateformes représentatives afin d’identifier les paramètres significatifs, aussi bien au niveau matériel qu’au niveau applicatif, à l’inverse de nombreux travaux dans lesquels ces paramètres sont assez peu pris en compte voir ignorés. Ce travail analyse et compare diverses expérimentations menées sur des politiques énergétiques basées sur des techniques DVFS (Dynamic Voltage and Frequency Scaling) et DPS (Dynamic Power Switching) et définit les conditions sous lesquelles ces stratégies sont efficaces. Ces expérimentations ont permis d’établir des conclusions remarquables qui peuvent servir de pré-requis lors de la définition de stratégies efficaces de gestion de la consommation. Ces résultats montrent également que pour obtenir des stratégies efficientes il est nécessaire de tenir compte du domaine applicatif. Enfin, il faut noter que les modèles de haut de niveau de consommation ont été définis sur la base des mesures effectuées et afin d’estimer les gains énergétiques dès les premières étapes d’un flot de conception. / The purpose of this study is to investigate how power management strategies can be efficiently exploited in actual platforms. Primarily, the challenges in multicore based embedded systems lies in managing the energy expenditure, determining the scheduling behavior and establishing methods to monitor power and energy, so as to meet the demands of the battery life and load requirements. The work presented in this dissertation is a study of low power-aware strategies in the practical world for single and multiprocessor platforms. The approach used for this study is based on representative multiprocessor platforms (real or virtual) to identify the most influential parameters, at hardware as well as application level, unlike many existing works in which these parameters are often underestimated or sometimes even ignored. The work analyzes and compares in detail various experimentations with different power policies based on Dynamic Voltage and Frequency Scaling (DVFS) and Dynamic Power Switching (DPS) techniques, and investigates the conditions at which these policies are effective in terms of energy savings. The results of these investigations reveal many interesting and notable conclusions that can serve as prerequisites for the efficient use of power management strategies. This work also shows the potential of advanced domain specific power strategies compared to real world available strategies that are general purpose based in their majority. Finally, some high level consumption models are derived from the different energy measurement results to let the estimation of power management benefits at early stages of a system development.
279

Deposition and preservation of estuarine sediment, Turnagain Arm, Cook Inlet, Alaska

DeBoer, Darron G. January 1900 (has links)
Master of Science / Department of Geology / Allen W. Archer / Turnagain Arm is the hypertidal (commonly exceeding 9 m) west-east trending extension of Cook Inlet in south-central Alaska. The inlet formed from a drowned glacial valley that was subsequently filled with tidal deposits of silt and fine sand. The tidal system is semidiurnal with a prominent diurnal inequality. There are also variations due to spring and neap tides. Turnagain Arm is home to a tidal bore generated during spring tides that can reach heights of up to 2 m and travel at speeds of up to 5 m/s. Current reversals can be dramatic with ebb tidal velocities of 6 m/s changing to flood velocities of 10 m/s over a period of a few minutes. During the initial flood tide, highly turbid water can rise as fast as 10 cm/min. This combination of elements results in a highly dynamic depositional setting. Measurements taken in the inner estuary during several neap-spring cycles in the summers of 2007-08 documented deposition upon mud bars of as much as 8.9 cm per tidal event. Conversely, erosion of up to 13.5 cm per tidal event has been measured. The highest rates of deposition and erosion occurred during the spring tides while much lower rates occur during the neap tides. Some portions of the inner estuary are only submerged during the extreme high tides. The magnitude of the high tide needed to cover each site increases with increasing distance into the upper estuary. Even if submerged, deposition does not always occur. Such a high percentage of non-depositional events has real implications when interpreting tidal cyclicity of the rhythmites found at these sites.
280

Inerciální navigační jednotka / Inertial Navigation Unit

Dvořák, Jan Unknown Date (has links)
This thesis is focused on the design and realisation of inertial navigation unit INS. The unit is capable to measure, store and send data to a PC in real-time for a later offline processing. The first part of the thesis introduces the reader with the basic principles of accelerometers, gyroscopes and MEMS sensors. An introduction to coordinate systems and measuring errors is also included. The second and third part of the thesis deals with the analysis of the solution and the implementation of the INS unit. The fourth part of the document is dedicated to the software for the INS unit. This thesis concludes with explanation how the gathered data are processed.

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