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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.
51

Eye Movement Analysis for Activity Recognition in Everyday Situations

Gustafsson, Anton January 2018 (has links)
Den ständigt ökande mängden av smarta enheter i vår vardag har lett till nya problem inom HCI så som hur vi människor ska interagera med dessa enheter på ett effektivt och enkelt sätt. Än så länge har kontextuellt medvetna system visat sig kunna vara ett möjligt sätt att lösa detta problem. Om ett system hade kunnat automatiskt detektera personers aktiviteter och avsikter, kunde det agera utan någon explicit inmatning från användaren. Ögon har tidigare visat sig avslöja mycket information om en persons kognitiva tillstånd och skulle kunna vara en möjlig modalitet för att extrahera aktivitesinformation ifrån.I denna avhandling har vi undersökt möjligheten att detektera aktiviteter genom att använda en billig, hemmabyggd ögonspårningsapparat. Ett experiment utfördes där deltagarna genomförde aktiviteter i ett kök för att samla in data om deras ögonrörelser. Efter experimentet var färdigt, annoterades, förbehandlades och klassificerades datan med hjälp av en multilayer perceptron--och en random forest--klassificerare.Trots att mängden data var relativt liten, visade resultaten att igenkänningsgraden var mellan 30-40% beroende på vilken klassificerare som användes. Detta bekräftar tidigare forskning att aktivitetsigenkänning genom att analysera ögonrörelser är möjligt. Dock visar det även att det fortfarande är svårt att uppnå en hög igenkänningsgrad. / The increasing amount of smart devices in our everyday environment has created new problems within human-computer interaction such as how we humans are supposed to interact with these devices efficiently and with ease. So far, context-aware systems could be a possible candidate to solve this problem. If a system automatically could detect people's activities and intentions, it could act accordingly without any explicit input from the user. Eyes have previously shown to be a rich source of information about a person's cognitive state and current activity. Because of this, eyes could be a viable input modality for extracting information from. In this thesis, we examine the possibility of detecting human activity by using a low cost, home-built monocular eye tracker. An experiment was conducted were participants performed everyday activities in a kitchen to collect eye movement data. After conducting the experiment, the data was annotated, preprocessed and classified using multilayer perceptron and random forest classifiers.Even though the data set collected was small, the results showed a recognition rate of between 30-40% depending on the classifier used. This confirms previous work that activity recognition using eye movement data is possible but that achieving high accuracy is challenging.
52

Liberte Egalite Sororite: Feminist Directing Strategies Applied to The Revolutionists at Miami University

Bledsoe, Stormi Danielle 01 August 2019 (has links)
No description available.
53

Development of Shoulder Joint Protection Program for People with Shoulder Arthritis: A Synthesis of Evidence and Developing Joint Protection Program for Daily Activities / Shoulder Joint Protection Program

Lu, Ze (Steve) January 2023 (has links)
This dissertation aimed to develop a joint protection program for people with shoulder arthritis. The program was developed throughout a two-phase process. The first stage in developing the Shoulder Joint Protection Program for patients with different stages of arthritis focused on comprehending existing research and understanding the factors that influence shoulder joint protection. We considered the priorities and preferences of both patients and therapists, integrating different types of evidence like systematic reviews, narrative and scoping reviews, and analysis of shoulder movement. This evidence guided the creation of a preliminary joint protection program. The second stage assessed the content validity of this program, using cognitive interviews with patients and therapists. The findings from each phase were then presented in separate chapters, providing a complete view of the Shoulder Joint Protection Program (SJPP) for individuals with shoulder arthritis. The evidence presented in Chapters 2 and 3 suggests that no single optimal program has been defined for patients undergoing total shoulder joint replacement surgery, including both anatomical and reversed types. Further high-quality RCTs are needed to provide more conclusive results. To assess outcomes, various patient-reported outcomes have been developed and validated. However, our study, as presented in Chapter 4, reveals inconsistencies and a lack of clarity in the conceptual frameworks of the identified PROMs. Our scoping review in Chapter 5 offers comprehensive research on shoulder biomechanics during various activities, and spotlights potential injury prevention strategies. These identified strategies can guide the creation of training programs, coaching practices, and rehabilitation strategies aimed at minimizing the risk of shoulder injuries and bolstering overall shoulder health. Results from Chapter 6 suggest that participants have the capacity to modify their movement patterns to implement joint protection strategies, potentially beneficial in post-surgery rehabilitation and enhancing shoulder function. The application of motion analysis software tools, such as MediaPipe, has yielded reliable results, indicating their potential for future kinematic studies. The developed SJPP comprises two sections: general joint protection principles and specific protective strategies for daily activities. Both digital resources and a printed version were developed to increase the accessibility of the program. The study (Chapter 7) presents a substantial contribution to the resources for patients with shoulder arthritis. It was designed to enhance their quality of life and enable them to navigate everyday activities with greater ease and less discomfort. Further enhancements, such as the inclusion of content on sports and recreational activities, could make the program even more comprehensive and beneficial. Overall, the study underscores the importance of evidence-based, user-friendly resources for patients with shoulder arthritis and provides potential directions for future research and enhancements, such as including content on sports and recreational activities. The SJPP's ultimate goal is to enhance patients' quality of life, allowing them to perform everyday activities with less discomfort. / Thesis / Doctor of Rehabilitation (RhD) / This Ph.D. research project set out to create a program to help people with shoulder arthritis protect their joints. The development process was broken down into two main stages. In the first step, we looked at what we already know from research and figured out the main things that affect how well someone can protect their shoulder joint. We thought about what patients and therapists want and need. We looked at many different kinds of studies and even how people move their shoulders. All this helped us make a first version of our plan. In the second step, we checked how good our plan was. We did this by talking with patients and therapists. We wrote about everything we found out in different chapters. This gave us a full picture of our Shoulder Joint Protection Program (SJPP) for people with shoulder arthritis. Our final SJPP has two main parts: general rules to protect the joint and special tips for everyday activities. We made it available online and on paper so it's easy to get. Our study is a big help for patients with shoulder arthritis. It's meant to make their lives better and help them do everyday things with less pain. In the future, we might add more tips about sports and fun activities, which could make it even more helpful. In conclusion, our research shows how important it is to have easy-to-use, research-based tools for patients with shoulder arthritis. We've also given some ideas for future research. The main goal of the SJPP is to make patients' lives better, helping them do everyday things with less pain.
54

Use of inertial sensors to measure upper limb motion : application in stroke rehabilitation

Shublaq, Nour January 2010 (has links)
Stroke is the largest cause of severe adult complex disability, caused when the blood supply to the brain is interrupted, either by a clot or a burst blood vessel. It is characterised by deficiencies in movement and balance, changes in sensation, impaired motor control and muscle tone, and bone deformity. Clinically applied stroke management relies heavily on the observational opinion of healthcare workers. Despite the proven validity of a few clinical outcome measures, they remain subjective and inconsistent, and suffer from a lack of standardisation. Motion capture of the upper limb has also been used in specialised laboratories to obtain accurate and objective information, and monitor progress in rehabilitation. However, it is unsuitable in environments that are accessible to stroke patients (for example at patients’ homes or stroke clubs), due to the high cost, special set-up and calibration requirements. The aim of this research project was to validate and assess the sensitivity of a relatively low cost, wearable, compact and easy-to-use monitoring system, which uses inertial sensors in order to obtain detailed analysis of the forearm during simple functional exercises, typically used in rehabilitation. Forearm linear and rotational motion were characterised for certain movements on four healthy subjects and a stroke patient using a motion capture system. This provided accuracy and sensitivity specifications for the wearable monitoring system. With basic signal pre-processing, the wearable system was found to report reliably on acceleration, angular velocity and orientation, with varying degrees of confidence. Integration drift errors in the estimation of linear velocity were unresolved. These errors were not straightforward to eliminate due to the varying position of the sensor accelerometer relative to gravity over time. The cyclic nature of rehabilitation exercises was exploited to improve the reliability of velocity estimation with model-based Kalman filtering, and least squares optimisation techniques. Both signal processing methods resulted in an encouraging reduction of the integration drift in velocity. Improved sensor information could provide a visual display of the movement, or determine kinematic quantities relevant to the exercise performance. Hence, the system could potentially be used to objectively inform patients and physiotherapists about progress, increasing patient motivation and improving consistency in assessment and reporting of outcomes.
55

Multi-body optimization method for the estimation of joint kinematics : prospects of improvement / Méthode d’optimisation multi-segmentaire pour l’estimation de la cinématique articulaire : propositions d’amélioration

Richard, Vincent 28 June 2016 (has links)
L'analyse du mouvement humain s'appuie généralement sur des techniques de suivi de marqueurs cutanés pour reconstruire la cinématique articulaire. Cependant, ces techniques d'acquisition présentent d'importantes limites dont les " artefacts de tissus mous " (i.e., le mouvement relatif entre les marqueurs cutanés et le squelette sous-jacent). La méthode d'optimisation multi-segmentaire viseà compenser ces artefacts en imposant aux trajectoires de marqueurs les degrés de liberté d'un modèle cinématique prédéfini. Les liaisons mécaniques modélisant classiquement les articulations empêchent toutefois une estimation satisfaisante de la cinématique articulaire. Cette thèse aborde des perspectives d'amélioration de la méthode d'optimisation multi-segmentaire pour l'estimation de la cinématique articulaire du membre inférieur,à travers différentes approches : (1) la reconstruction de la cinématique par suivi de la vitesse angulaire, de l'accélération et de l'orientation de centrales inertiellesà la place du suivi de marqueurs, (2) l'introduction d'un modèle articulaire élastique basé sur la matrice de raideur du genou, permettant une estimation physiologique de la cinématique articulaire et (3) l'introduction d'un modèle des artefacts de tissus mous " cinématique-dépendant ", visantà évaluer et compenser les artefacts de tissus mous simultanément avec l'estimation la cinématique articulaire. Ce travail a démontré la polyvalence de la méthode d'optimisation multi-segmentaire. Les résultats obtenus laissent espérer une amélioration significative de cette méthode qui devient de plus en plus utilisée en biomécanique, en particulier pour la modélisation musculo-squelettique / Human movement analysis generally relies on skin markers monitoring techniques to reconstruct the joint kinematics. However, these acquisition techniques have important limitations including the "soft tissue artefacts" (i.e., the relative movement between the skin markers and the underlying bones). The multi-body optimization method aims to compensate for these artefacts by imposing the degrees of freedom from a predefined kinematic model to markers trajectories. The mechanical linkages typically used for modeling the joints however prevent a satisfactory estimate of the joint kinematics. This thesis addresses the prospects of improvement of the multi-body optimization method for the estimation of joint kinematics of the lower limb through different approaches: (1) the reconstruction of the kinematics by monitoring the angular velocity, the acceleration and the orientation of magneto-inertial measurement units instead of tracking markers, (2) the introduction of an elastic joint model based on the knee stiffness matrix, enabling a physiological estimation of joint kinematics and (3) the introduction of a "kinematic-dependent" soft tissue artefact model to assess and compensate for soft tissue artefact concurrently with estimating the joint kinematics. This work demonstrated the versatility of the multi-body optimization method. The results give hope for significant improvement in this method which is becoming increasingly used in biomechanics, especially for musculoskeletal modeling
56

La reconstruction du mouvement du squelette : l'enjeu de l'artefact des tissus mous / The reconstruction of skeletal movement : the soft tissue artefact issue

Bonci, Tecla 08 May 2015 (has links)
Lors de l'analyse 3D du mouvement humain basée sur des marqueurs cutanés, la position des os ne peut être qu'indirectement estimée. Au cours d'une tâche, les déformations des tissus mous génèrent des déplacements des marqueurs par rapport à l'os : les artefacts de tissus mous (STA), entraînant des effets dévastateurs sur l'estimation de la position. La compensation des STA demeure une question ouverte. L'objectif de cette thèse est de contribuer à la solution de cette question cruciale. La modélisation des STA en utilisant des variables spécifiques mesurables est une condition préalable à son élimination. Un modèle corrigeant les trajectoires individuelles de marqueurs de la cuisse, calibré par des mesures directes des STA, est d'abord présenté. Les STA sont modélisés comme une combinaison linéaire des angles articulaires impliqués. Trois représentations des STA par une série de modes sont proposées : déplacements de marqueurs individuels, transformations géométriques de clusters de marqueurs (MCGT), et variations de forme de l'enveloppe de peau. Le MCGT permet de dissocier les composantes rigides et non rigides. Il a été démontré que seule la composante rigide affecte la cinématique articulaire. Un modèle de cette composante est alors défini pour les clusters cuisse et jambe. Un compromis acceptable entre la correction des STA et le nombre de paramètres a ainsi été obtenu. Les principales applications sont de générer une simulation réaliste des STA ; et surtout, en se concentrant sur la composante rigide, le modèle permet une reconstruction satisfaisante des STA avec moins de paramètres, ce qui facilite son incorporation dans un algorithme d'estimation de la position osseuse / In 3D human movement analysis performed using stereophotogrammetry and skin markers, bone pose can be only indirectly estimated. During a task, soft tissue deformations make the markers move with respect to the underlying bone generating soft tissue artefacts (STA), causing devastating effects on pose estimation and its compensation remains an open issue. The thesis’ aim was to contribute to the solution of this crucial issue. Modelling STA using measurable trial-specific variables is a prerequisite for its removal from marker trajectories. Two STA model architectures are proposed. A thigh marker-level model is first presented. STA was modeled as a linear combination of joint angles involved in the task. The model was calibrated with direct STA measures. The considerable number of model parameters led to defining STA approximations. Three definitions were proposed to represent STA as series of modes : individual marker displacements, marker-cluster geometrical transformations (MCGT), and skin envelope shape variations. Modes were selected using two criteria : modal energy and selecting them a priori. The MCGT allows to select either rigid or non-rigid components. It was also demonstrated that only the rigid component affects joint kinematics. A model of thigh and shank rigid component at cluster-level was then defined. An acceptable trade-off between STA compensation and number of parameters was obtained. These results lead to two main potential applications : generate realistic STAs for simulation
57

Les altérations des mouvements rotatoires de l'épaule après lésion obstétricale du plexus brachial: clinique, chirurgie et analyse de facteurs pronostiques objectifs / Changes in rotatory movements of the shoulder after obstetric brachial plexus lesion: clinical condition, surgery, and analysis of objective prognostic factors

Bahm, Jorg 05 May 2011 (has links)
The most frequent sequelae following an obstetric brachial plexus lesion without complete functional recovery concern the impaired shoulder rotation movements and the associated structural changes of the growing glenohumeral joint. <p>This pathology is often unrecognized and may lead to a limitation in active movements, a pathologic and less efficient motion pattern in the affected limb, and the development of a severely incongruent and dysplastic glenohumeral joint prone to further arthrosis.<p><p>Hypothesis<p><p>Glenohumeral dysplasia after obstetric brachial plexus lesion has multiple etiologies: A hypothetic obstetric trauma may precede the motor imbalance, due to the initial palsy and prevalent recovery of the medial rotators of the shoulder.<p>The correction of the muscular imbalance, by neurotization of the lateral rotators (supra- and infraspinatus muscle) using a local nerve transfer or by a later muscle transfer surgery, improves function, seems to prevent the development of joint dysplasia and limits the articular deformities once they are present. <p>The early (peripartal) glenohumeral subluxation must be recognized and treated immediately to prevent the development of a severe joint contracture and dysplasia.<p> <p>Material and methods<p><p>Two retrospective and one prospective study evaluate how surgery may correct the muscular imbalance.<p>In a first series of 65 children, we analyse the recovery of the supra- and infraspinatus muscle after a nerve transfer onto the suprascapular nerve.<p>In a second retrospective analysis on 114 children, we study the outcome after secondary surgery (anterior joint release, modified Hoffer muscle transfer) dedicated to improve active and passive lateral rotation of the shoulder.<p>A prospective study of 50 magnetic resonance (MRI) scans of the glenohumeral joint describes the articular deformities.<p>Finally, 10 children presenting a very early glenohumeral subluxation have undergone a closed orthopaedic reposition and plaster immobilisation and were followed for a minimum of 2 years.<p><p>Results<p><p>In the first group, neurotization of the suprascapular nerve has been performed either by a dorsal or a ventral approach at a mean age of 14 months. The mean follow up is of 3 years and the improvement in aLR(ABD) is 68°and only 25°in aLR(ADD). None of these children with improved active lateral rotation of the shoulder developed clinical signs of a glenohumeral dysplasia within the follow up period.<p><p>Among the 114 children operated between 6 months and 44 years with a shoulder release, 74 had an isolated release procedure, 40 an associated tendon transfer or a suprascapular neurotization. The mean improvement in passive lateral rotation with the arm adducted (pLR (ADD)) was 60°. Active lateral rotation was possible in 63 % of children who underwent an isolated joint release.<p>The Hoffer muscle transfer was performed in 29 children and improved the aLR (ABD) by 60° (mean postoperative follow-up of 30 months). No signs of severe glenohumeral dysplasia developed in these children later on.<p><p>The prospective study of 50 consecutive MRI scans in children presenting at the consultation with a rotatory imbalance of their shoulder, as a sequel from obstetric brachial plexus palsy (Bahm et al. 2007) shows 37 congruent joints, 10 dorsal subluxations, 2 dorsal luxations and one complete dislocation associated with the formation of an independent neoglenoid. The humeral head was deformed in 12 cases; the glenoid in 34 children (flat in 23, biconcave 7 times, convex 3 times).<p><p>The follow up of 2 years in 10 children who underwent an immediate closed reposition shows evidence of joint congruence with a limited (30°) pLR (ADD), definitely lower than after a surgical release.<p><p>Conclusion<p><p>Some osteo-articular deformities secondary to neuromuscular diseases are well described ;those following an obstetric brachial plexus lesion are insufficiently recognized. Their etiology is unclear.<p>At the level of the shoulder joint, these sequels might be very important.<p>Our neuroorthopaedic hypothesis concerning a multifactorial etiology and treatment strategy raises the need of an early and precise screening of the deforming forces to render normal biomechanics and function.<p>The surgical strategy includes the reconstruction of the responsible motor nerve and the improvement of the passive and active range of motion of the shoulder in lateral rotation<p>It seems to be efficient to limit the progression to severe glenohumeral dysplasia and further arthrosis.<p> / Doctorat en Sciences médicales / info:eu-repo/semantics/nonPublished
58

Měřicí zařízení pro sportovní analýzu využívající senzory inerciálních veličin / Measurement unit for sports analysis with inertial sensors

Dugas, Martin January 2018 (has links)
Master's thesis is dealing with desgin of a measuring unit incorporating inertial sensors, used for analysis in canoe sprint. Data from a three-axis accelerometer and a three-axis gyroscope were combined using an extended Kalman filter, yielding speed, roll, pitch and yaw of the boat and stroke rate. Calculated values were verified by a GPS. Furthermore, parameters describing dynamic behaviour of the system were identified, allowing an inclusion of dynamic quantities like force and power into the analysis.
59

Practical studies on bike fitting - A biomechanical and physiological analysis under the influence of fatigue

Dully, Jonas, Bartaguiz, Eva, Dindorf, Carlo, Becker, Stephan, Fröhlich, Michael 14 October 2022 (has links)
Bike fitting can have a major impact on the performance of cyclists and can reduce the risk of non-traumatic injuries. This study shows significant changes in lower body biomechanics of road cyclists during and after fatigue and therefore expands the research from a more practical view. These findings support the expansion of future research using sensor-based analyses of road cycling (e.g., IMUs, oxygen saturation). / Die Einstellung des Fahrrads kann einen großen Einfluss auf die Leistung von Radfahrern haben und das Risiko nichttraumatischer Verletzungen verringern. Diese Studie zeigt signifikante Veränderungen in der Biomechanik des Unterkörpers von Rennradfahrern während und nach der Ermüdung und erweitert damit die Forschung aus einer eher praktischen Sicht. Diese Ergebnisse unterstützen die Ausweitung zukünftiger Forschung unter Verwendung sensorbasierter Analysen des Straßenradsports (z. B. IMUs, Sauerstoffsättigung).

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