Deep Wild är ett företag som bland annat   specialiserar sig på produktutveckling och byggande av äventyrsanläggningar.   Kunder till företaget har efterfrågat ett typ av äventyrstorn som det är   möjligt att åka zipline från samt utföra andra aktiviteter såsom klättring   på. Då Deep Wild inte har egen kompetens gällande dimensionering och   projektering av denna typ av torn har en förfrågan skickats ut till studenter   för att se om det fanns intresse att ta fram en lösning på utförandet. Syftet   med arbetet är att undersöka hur ett äventyrstorn som detta kan konstrueras   och ta fram en lösning på utförandet. Tornet dimensioneras enligt gällande   Eurokoder. De laster som genereras av specialutrustningen tornet förses med   finns i Svensk Standard. Två lösningar på möjliga utföranden tas fram, ett   med alla bärande delar i stål och ett med lämpliga bärande delar i trä. Dessa   jämförs sedan med hänsyn till lämplighet. Det visar sig att det finns många   fördelar med att bygga tornet med enbart stålprofiler. Med stål som material kan   alla bärande delar köpas ur det lagerförda sortiment som erbjuds på   marknaden. Med trä finns inga lagerförda dimensioner att tillgå för de laster   som uppstår. Vid de knutpunkter som dimensionerats visar det sig att de   utförda i stål enkelt kan utföras så att de har mycket god säkerhetsmarginal.   Knutpunkterna i träkonstruktionen klarar de dimensionerande lasterna endast   med små marginaler. Genom att mer specialanpassa utseendet hos konstruktionen   och dess verkningssätt så kan möjligtvis utförandet i trä gynnas. En   prisjämförelse mellan de två materialen visar att skillnaden i materialpris   är försumbar i sammanhanget. Två alternativa stabiliseringssystem undersöks   för tornet. Det ena är att staga med en fackverkskonstruktion som använder   sig av dragna stålstänger och tryckta strävor av respektive   utförandematerial. Det andra är att staga tornet genom skivverkan i   klätterväggen som uppförs på tornets ena sida. Skivverkan har sina fördelar   då det möjliggör tryckta strävor på olika höjd i tornet. Fackverkskonstruktionen   är dock att rekommendera då denna kan dimensioneras att ta avsevärt högre   laster. Det naturliga nästa steget i arbetet ligger i att ta fram ett   förfrågningsunderlag tillräckligt komplett för att kalkyleras. / Deep Wild is an   adventure company which specializes in product development among other   things. Customers of the company have been asking for a tower from which it’s   possible to exercise different kinds of adventure activities, such as   ziplining and climbing. Deep Wild doesn’t have in house experience from   constructing supporting structures that are not directly related to the   special equipment used to exercise these activities. Therefore students have   been asked to find a solution on how to construct a tower like this. The   purpose of this study is to investigate how an adventure tower can be   constructed. The tower is structurally designed using Eurocodes and the loads   generated from the activities exercised appear in European Standard. Two   possible solutions for the construction is developed, one with all supporting   parts in steel and one with selected supporting parts in wood. These are then   compared to each other with regard to their performance. The results show   that there are many advantages using only steel profiles. All steel profiles   required for the construction can be bought out of existing stock from   producers. To use wooden profiles it is required to place orders on standard   dimensions that are not part of the producers existing stock. The joints designed   shows that using steel profiles these can easily be designed to provide a   high safety margin. The joints designed using steel connectors to wooden   profiles provides enough support only with small safety margins. By adjusting   the design of the towers supporting system the use of wooden profiles could   possibly be benefitted. A price comparison based on the price of material   shows that the difference between laminated timber and steel in this   construction is negligible. Two alternative ways of stabilizing the tower   have been investigated. One with tensioned steel bracing and compressed   bracing using the different construction materials. The other one using wall   diaphragms on the side of the tower clad with climbing wall. The wall   diaphragms method has its advantages because it makes it possible to place   compressed bracings on different heights in the tower. The system with   tensioned bracings can take higher loads and provide better safety margins   and is therefore the recommended way of stabilizing this tower. The next step   of this project is to provide complete enough material to calculate the cost   of constructing. / <p>Betyg 2018-06-05</p>

Heteroscedasticity (or time-dependent volatility) in economic and financial time series has been recognized for decades. Still, heteroscedasticity is surprisingly often neglected by practitioners and researchers. This may lead to inefficient procedures. Much of the work in this thesis is about finding more effective ways to deal with heteroscedasticity in economic and financial data. Paper I suggest a filter that, unlike the Box-Cox transformation, does not assume that the heteroscedasticity is a power of the expected level of the series. This is achieved by dividing the time series by a moving average of its standard deviations smoothed by a Hodrick-Prescott filter. It is shown that the filter does not colour white noise. An appropriate removal of heteroscedasticity allows more effective analyses of heteroscedastic time series. A few examples are presented in Paper II, III and IV of this thesis. Removing the heteroscedasticity using the proposed filter enables efficient estimation of the underlying probability distribution of economic growth. It is shown that the mixed Normal - Asymmetric Laplace (NAL) distributional fit is superior to the alternatives. This distribution represents a Schumpeterian model of growth, the driving mechanism of which is Poisson (Aghion and Howitt, 1992) distributed innovations. This distribution is flexible and has not been used before in this context. Another way of circumventing strong heteroscedasticity in the Dow Jones stock index is to divide the data into volatility groups using the procedure described in Paper III. For each such group, the most accurate probability distribution is searched for and is used in density forecasting. Interestingly, the NAL distribution fits best also here. This could hint at a new analogy between the financial sphere and the real economy, further investigated in Paper IV. These series are typically heteroscedastic, making standard detrending procedures, such as Hodrick-Prescott or Baxter-King, inadequate. Prior to this comovement study, the univariate and bivariate frequency domain results from these filters are compared to the filter proposed in Paper I. The effect of often neglected heteroscedasticity may thus be studied.

L'utilisation des informations proprioceptives pour le contrôle de l’équilibre à la marche est encore mal comprise chez les sujets en santé ou hémiparétiques suite à un accident vasculaire cérébral. Le but de cette étude était d’évaluer le rôle des informations proprioceptives dans le maintien de l'équilibre à la marche chez les patients en santé et hémiparétiques. Une analyse de mouvement en trois dimensions a été faite chez treize participants en santé et six hémiparétiques qui marchaient sur un tapis roulant instrumenté pour déterminer leur difficulté à maintenir l’équilibre postural et dynamique, évaluée respectivement par les forces stabilisante et déstabilisante. Des vibrations étaient appliquées en continu ou pendant la phase d’appui sur les muscles postérieurs du cou et sur le triceps sural du côté non-dominant/parétique. La vibration continue ou à l’appui du triceps sural a diminué, chez les sujets en santé, la difficulté à maintenir l’équilibre dynamique et postural (p< 0,01), avec une position du corps plus en arrière, sans changement des paramètres temporels de marche. L'équilibre et les paramètres temporels de la marche n'étaient pas modifiés significativement par la vibration à la nuque (p>.17). Aucun effet des vibrations n'a été mesuré chez les patients hémiparétiques (p> 0,45). Les informations proprioceptives sont donc bien utilisées lors de la marche, mais leur rôle dépendrait des conditions de marche et des afférences visuelles disponibles. Un changement dans les capacités d’intégration expliquerait l'absence d'effet des vibrations chez les patients hémiparétiques. D’autres études sont nécessaires pour comprendre l’intégration des informations proprioceptives et visuelles dans le contrôle de l’équilibre à la marche. / Proprioceptive information is important for balance control, but little is known about how it is used during gait, or how stroke affects this use. The aim of this study was to evaluate the role of neck and ankle proprioception in balance during gait in healthy participants and after stroke. Thirteen healthy and 6 hemiparetic participants walked on an instrumented treadmill in a fully lit room, while whole-body three-dimension kinematics was quantified. Vibration was applied on the posterior neck muscles and triceps surae tendon on the non-dominant/paretic side, continuously or during the stance phase only. Difficulty to maintain dynamic and postural balance was evaluated using the stabilizing and destabilizing forces, respectively. Summary data of gait kinematics and kinetics were also reported. Continuous and stance phase vibration of the triceps surae decreased, in healthy patients, the difficulty to maintain both dynamic and postural balance in healthy participants (p<.01), with a longer distance between the centre of mass and centre of pressure and the limit of the base of support, indicating a more backward body position, and no change in temporal gait parameters. No effect of neck muscle vibration was observed (p>.17). None of the vibration conditions affected balance or gait parameters in stroke participants. The results confirmed that proprioception information is used for control balance during gait. Its importance depends on the walking and visual conditions. Changes in sensory integration capacities likely explain the results after stroke. Further study is needed to understand the integration of proprioception and vision information to control balance during gait.

Nous proposons un algorithme original de structuration des réseaux ad hoc nommé SDEAC dans le but d'optimiser les communications et de tolérer les pannes transitoires. SDEAC est auto-stabilisant, distribué et déterministe. Il utilise un modèle asynchrone à passage de messages et se fonde sur un voisinage à distance 1 pour construire des clusters non-recouvrants à k sauts. Nous montrons que partant d'une configuration quelconque et sans occurrence de pannes transitoires, SDEAC structure le réseau dans le pire des cas en n+2 transitions. En outre, son exécution nécessite une occupation mémoire de (Δu+1)*log(2n+k+3) bits pour chaque noeud u, avec Δu étant le degré de u, k le rayon maximal des clusters et n la taille du réseau. Par simulation sous OMNeT++, nous observons pour un réseau quelconque un temps de stabilisation très inférieur à celui du pire des cas d'une part. D'autre part, suite à l'occurrence de pannes transitoires après la stabilisation, nous constatons un temps de stabilisation inférieur à celui du clustering. Dans le contexte des RCSF, nous étudions la consommation énergétique de SDEAC suivant trois critères d'élection des cluster-heads (identité, degré et énergie résiduelle des noeuds) puis nous la comparons avec celle de la solution de Mitton et al. opérant dans le même modèle. Les résultats montrent que SDEAC permet le passage à l'échelle et réduit la consommation énergétique de 42% à 49%. Enfin, pour l'utilisation de SDEAC dans l'acheminement de l'information, nous proposons deux approches efficaces : (i) un routage sans agrégation qui minimise les délais de bout en bout et (ii) un routage avec agrégation partielle qui réduit la consommation énergétique totale offrant ainsi une meilleure durée de vie du réseau. / We propose SDEAC, a self-Stabilizing Distributed Energy-Aware and fault-tolerant Clustering algorithm. SDEAC uses an asynchronous message-passing model and is based on 1-hop neighboring to build non-overlapping k-hops clusters. We prove that, starting from an arbitrary configuration, SDEAC structures the network after at most n + 2 transitions and requires (Δu+1)log(2n+k+3) memory space for each node u, where n is the number of network nodes, Δu is the degree of u and k represents the maximum hops number. Through simulations under OMNeT++, we observe that over arbitrary network, the stabilization time is far below the worst case scenario. Furthermore, we remark that after faults, the re-clustering cost is significantly lower than the clustering cost. In the context of Wireless Sensor Networks (WSNs), we evaluate the energy consumption of SDEAC according to multiple criteria in the election of cluster-heads, such as nodes' identity, residual energy or degree and we compare it with the well-known message-passing based self-stabilizing clustering algorithm proposed by Mitton et al. Results show that SDEAC is scalable and reduces energy consumption between 42% and 49%.Afterwards, we propose efficient scenarios in order to transfer information: (i) the non-aggregation scenario that provides a better end-to-end delay and (ii) the partially-decentralized aggregation scenario that reduces the total energy consumption and prolongs the network lifetime.

Les processus auto-stabilisants sont définis comme des solutions d'équations différentielles stochastiques dont le terme de dérive contient à la fois le gradient d'un potentiel ainsi qu'un terme non-linéaire au sens de McKean qui attire le processus vers sa propre loi de distribution. On dispose de nombreux résultats lorsque l'environnement est convexe. L'objet de ce travail est de les étendre autant que possible au cas général notamment lorsque le paysage contient plusieurs puits. Des différences fondamentales sont constatées.Le premier chapitre prouve l'existence d'une solution forte. Le second s'intéresse aux lois de probabilités d'une telle solution. En particulier, l'existence et la non-unicité des mesures stationnaires sont mises en évidence sous des hypothèses faibles. Les chapitres trois et quatre sont affectés au comportement de ces mesures lorsque le coefficient de diffusion tend vers 0.Le chapitre cinq met en relation le processus auto-stabilisant avec des systèmes particulaires via une « propagation du chaos ». Il est ainsi possible de transposer certains résultats du système de particules sur le processus non-markovien et réciproquement. Le chapitre six est dédié au dénombrement exact des mesures stationnaires.Le chapitre sept est employé pour l'étude du comportement en temps long. D'une part, un résultat de convergence dans un cas simple est fourni. D'autre part, un principe de grandes déviations est mis en évidence par l'utilisation des résultats de Freidlin et Wentzell / Self-stabilizing processes are defined as the solutions of stochastic differential equations which drift term contains the gradient of a potential and a term nonlinear in the sense of McKean which attracts the process to its own law distribution. There are many results if the landscape is convex. The purpose of this work is to extend these in the general case especially when the landscape contains contains several wells. Essential differences are found.The first chapter proves the strong existence of a solution. The second one deals with the probability measure of the solution. Particularly, the existence and the non-uniqueness of the stationary measures are highlighted under weak assumptions. Chapter three and four are assigned to the asymptotic analysis in the small noise limit of these measures.Chapter five connects the self-stabilizing process and some particle systems via a « propagation of chaos ». It is thus possible to translate some results from the particle systems to the non-markovian process and reciprocally.Chapter seven is used to study the long time behavior. In one hand, a convergence's result is provided in a simple case. In the other hand, a large deviations principle is highlighted by using the results of Freidlin and Wentzell

Inclined planes and stairs are current in the environment and represent a barrier for seniors and people with mobility problems. Slower progression, alteration in gait pattern likely explains the high rate of fall on these surfaces, but their effect on balance is not well known. Our objective was thus to compare the difficulty in maintaining dynamic stability during the ascent and descent of an inclined plane and stairs at natural and slow walking speed in healthy individuals. Ten young healthy participants ascended and descended an inclined plane and stairs, instrumented with force- platforms to record ground reaction forces. Whole-body kinematics was also recorded to determine balance difficulty using the stabilizing and destabilizing forces, center of mass velocity and step length. Analyses of variance were used to compare the effect of surface (inclined plane vs. stairs), direction (ascent vs. descent) and speed (natural vs. slow). The stabilizing force was higher on the inclined plane than on the stairs, with a higher velocity of the center of mass. Stabilizing force was higher and destabilizing force was lower during descent than ascent only in the inclined plane but destabilizing force was lower during ascent than descent on the stairs. Slower gait speed reduced balance difficulty on both surfaces. Step length was shorter in the stairs than on the inclined plane, and particularly during descent, and at slow gait speed. Balance difficulty was higher on the inclined plane than on the stairs and at natural speed than at slow speed. The effect of direction was opposite between surfaces with higher difficulty during descent of the inclined plane, but during ascent of the stairs. Further studies are necessary in older adults or individuals with balance deficits. / La présence d’un escalier ou d’un plan incliné constitue souvent un obstacle sérieux à la réalisation des habitudes de vie des personnes ayant des incapacités physiques et même chez les personnes âgées. L’objectif général de cette étude était de quantifier l’équilibre dynamique lors de la négociation (montée et descente) d’un escalier et d’un plan incliné chez des sujets en santé. Dix sujets en santé ont été recrutés pour participer à l’évaluation. Les participants ont effectué la montée et la descente du plan incliné et de l’escalier à vitesse naturelle puis à vitesse lente. L’évaluation a compris un enregistrement de la cinématique de l’ensemble du corps. L’ensemble des données ont servi à analyser la force déstabilisante, la force stabilisante, la vitesse du centre de masse et la longueur de pas. Des ANOVAs et des tests t de Student ont permis de comparer l’effet de la surface (plan incliné vs. Escalier), de la direction (montée vs. Descente) et de la vitesse (naturelle vs. lente). La force stabilisante était plus élevée sur le plan incliné qu’à l’escalier, avec une vitesse de centre de masse plus élevée. La force stabilisante était plus élevée et la force déstabilisante était plus basse durant la descente en comparaison avec la montée sur le plan incliné. Par contre, à l’escalier, la force déstabilisante était plus basse lors de la montée en comparaison avec la descente. La vitesse de marche lente a réduit la difficulté en termes d’équilibre sur les deux surfaces. Les pas étaient plus courts sur l’escalier en comparaison avec le plan incliné, particulièrement lors de la descente à vitesse naturelle. L’effet de direction était opposé entre les surfaces, avec une difficulté plus élevée durant la descente du plan incliné et durant la montée de l’escalier. Des études approfondies seront nécessaires chez les personnes âgées et les personnes ayant des déficits de la balance.

Metastable paramagnetic face-centered cubic (fcc) Fe thin films deposited on a Cu(100) single-crystal are good candidates for focused ion-beam magnetic patterning, due to their structural and magnetic phase transformation to ferromagnetic body-centered cubic (bcc) Fe upon ion-beam irradiation. However, pure fcc Fe films undergo spontaneous transformation when their thickness exceeds 10 ML. This limit can be extended to approximately 22 ML by deposition of Fe at increased CO background pressures. We show that much thicker films can be grown by alloying with Ni, that stabilizes the fcc phase. The amount of Ni necessary to stabilize non-magnetic, metastable fcc Fe films in dependence on the residual background pressure during the deposition is determined and a phase diagram revealing the metastable region is presented. It is also shown that the stabilizing effect of CO can be removed by artificial O saturation of the surface and thus the Ni-stabilized films can be grown also in systems with lower vacuum. Finally, we present fabrication of micro- and nanostructures in 44 ML thick films of Fe alloyed with Ni on Cu(100) by focused ion beam.

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1 Abstract Title: Exploitation of regular exercise based on the elements of developmental kinesiology for people suffering with back pain. Objectives: The aim of my diploma thesis was observing the effect of a group motional program based on tenets of developmental kinesiology for function of the motional system of clients suffering from back pain. Methods: The theoretical part of my diploma thesis was done with a method of literary recherché using technical literature, articles and studies. Experiment was chosen for the practical part, quasi in particular, which was complemented by method of qualitative research, personal case study in particular. There are two clinical casuistries paced in my thesis. There were two following methods for collecting data during my research: kinesiology analysis focused on anamnesis, check-up by sight, check-up by touch and functional probing (dynamic check-up of spine, diagnostically testing of deep stabilizing muscles.) Another methods used in my diploma thesis were assessments of pain with a usage of visual analogy scale and semi-structured interview. Pre-tests and post-test were identical. 10 people suffering from chronic back pain in an area of cervical spine or lumbar spine (5 clients suffering from chronic back pain in an area of lumbar spine and 5 clients suffering...

This bachelor thesis is about the design and construction of a self-stabilizing platform. The purpose of this system is to balance objects placed upon the platform by keeping the platform level regardless of how the mechanism itself is rotated. Its uses include stabilization of sensors, cameras and vehicle cockpits. The prototype was constructed using 3D printing and basic machining. It uses two DC motors, an inertial measurement unit, an Arduino Uno microcontroller and a motor driver. The inertial measurement unit acts as an accelerometer and gyroscope, it measures the change in position and angle relative to its starting position. The controller algorithm processes the sensor signal and calculates an appropriate output signal. This output signal regulates the two DC motors in such a way that compensates for any angle changes in the platform. This project is based on, and is the continuation of the work by J. Larsson, titled ”Gimbal stabilizer for cockpit bases of terrain vehicle or combat boat: A proof of concept”. The task is to develop it to a functioning physical prototype and implement a control system which is fast, responsive and precise. The controller tuning process involved a trial and error approach, using binary search between parameters that give a performance that is too slow and a performance that is too fast and unstable. A satisfactory performance was achieved and the platform could effectively stabilize objects that weigh 400 grams at its center, 200 grams at its edges and 100 grams at its corners. This takes 100 milliseconds on average. Besides bearing loads, the platform could also compensate for sudden forced angle changes and any tilting of the mechanism the platform is attached to. / Det här kandidatexamensarbetet handlar om konstruktionen och framtagningen av en prototyp för en självstabiliserande plattform med ändamålet att hålla ett objekt horisontellt stabil. Det innebär att oberoende av hur mekanismen vrids eller rör sig kommer plattformen alltid vara parallell med marken. Appliceringsområden för plattformen kan vara att stabilisera kameror och sensorer, samt att hålla förarkabinen i en båt horisontellt stabil oavsett hur vattnet runtomkring rör sig. Prototypen består av en 3D-printad mekanism med två likströmsmotorer, en tröghetssensor, Arduino och motordrivare. Tröghetssensorn fungerar som en accelerometer och gyroskop - den avläser hur mycket plattformen ändrar sitt läge och vinkel relativt de ursprungliga. Data från tröghetssensorn bearbetas i en Arduino Uno-mikrokontroller med hjälp av reglerteknik, där en så kallad PID-regulator beräknar utsignal beroende på insignal. Arduinon skickar sedan utsignalen till motordrivaren som reglerar likströmsmotorerna för att kompensera för eventuella vinkeländringar. Detta projekt ¨ar ett utvecklingsarbete av ett tidigare masterexamensarbete av J. Larsson, med titeln ’ ’Gimbal stabilizer for cockpit bases of terrain vehicle or combat boat: A proof of concept”. Målet är att gå från ett koncept till en praktisk och verklighetsbaserad prototyp, samt att designa en regulator med god precision, stabilitet och responstid. För att bestämma hur regulatoralgoritmen ska fungera användes binärsökning för att hitta vilka P, I och D-värden PID-regulatorn ska ha. Det innebär att man ständigt tar ett medelvärde av en för långsam regulator och en som är för snabb och aggressiv tills önskad prestanda uppnås. Den slutgiltiga prestandan ansågs vara tillräcklig och plattformen kunde effektivt stabilisera 400 gram i mitten på den, 200 gram på dess sidor och 100 gram på dess hörn på ungefär 100 millisekunder. Vidare kunde den kompensera för plötsliga påtvingade vinkeländringar och för lutning hos mekanismen som den sitter fast i.