Flexible pipes are essential components in the subsea oil and gas industry, where they are used to convey fluids under conditions of extreme external pressure and (often) axial load, while retaining low bending stiffness. This is made possible by their complex internal structure, consisting of unbonded components that are, to a certain extent, free to move internally relative to each other. Due to the product's high value and high cost of testing facilities, much e ort has been invested in the development of analytical and numerical models for simulating flexible pipe behaviour, which includes bulk response to various loading actions, calculation of component stresses and use of this data for component fatigue calculations. In this work, it is proposed that the multi-scale methods currently in widespread use for the modelling of composite materials can be applied to the modelling of flexible pipe. This allows the large-scale dynamics of an installed pipe (often several kilometers in length) to be related to the behaviour of its internal components (with characteristic lengths in millimeters). To do this, a formal framework is developed for an extension of the computational homogenisation procedure that allows multiscale models to be constructed in which models at both the large and small scales are composed of different structural elements. Within this framework, a large-scale flexible pipe model is created, using a two-dimensional corotational beam formulation with a constitutive model representative of flexible pipe bulk behaviour, which was obtained by further development of a recently proposed formulation inspired by the analogy between the flexible pipe structural behaviour and that of plastic materials with non-associative flow rules. A three-dimensional corotational formulation is also developed. The model is shown to perform adequately for practical analyses. Next, a detailed finite element (FE) model of a flexible pipe was created, using shell finite elements, generalised periodic boundary conditions and an implicit solution method. This model is tested against two analytical flexible pipe models for several basic load cases. Finally, the two models are used to carry out a sequential multi-scale analysis, in which a set of simulations using the detailed FE model is carried out in order to find the most appropriate coefficients for the large-scale model.

- Flexible forms of employment This thesis deals with the flexible forms of employment as an alternative to an indefinite term employment with eight-hour working days and as an instrument for increasing employment relationship flexibility. These forms of employment, also called atypical or precarious, are attractive for employees who want to achieve a balance between their professional and personal lives, or for employers who can use these forms of employment as a competitive advantage or as an instrument to solve their economic problems. The thesis is divided into introduction, conclusion and five chapters which are divided into sub-chapters. The first chapter briefly describes the terms and principles which are important for the characterization of flexible forms of employment. The second chapter contains the definition of flexible forms of employment, their enumeration and brief summary of the survey on how czech employers use the flexible forms of employment. The third chapter deals with the flexible forms of employment provided for in the Labour Code. Namely fixed-term contract, agency employment, agreements on work carried out beyond employment, part-time job and homeworking. The next chapter deals with the forms which are not contained in the Labour Code, namely job sharing, compressed...

Tato diplomová práce se zaměřuje na mezinárodní právní nástroje ochrany klimatu, zejména flexibilní mechanismy v kontextu Kjótského protokolu a Evropský systém pro obchodování s povolenkami na emise ("EU ETS"). První kapitola představuje vědecké teorie zabývající se změnou klimatu. Ve druhé kapitole je shrnut historický vývoj mezinárodní činnosti v oblasti ochrany klimatu. Ve třetí kapitole se nachází analýza principů vztahujících se k ochraně klimatu a úprava flexibilních mechanismů. Následující kapitola analyzuje ochranu klimatu v kontextu EU. Pátá kapitola detailněji analyzuje EU ETS, jeho praktické aspekty a další vývoj. Powered by TCPDF (www.tcpdf.org)

Flexible forms of employment This diploma thesis deals with the flexible forms of employment as an alternatives to regular form of employment. The focus of the first two chapters is to determine the basic terms regarding the topic of this thesis; the following chapter concentrates on the flexible forms of employment regulated by Czech law in particular, i.e. Fixed-term contract, part-time job, homeworking, agreements on work carried out beyond employment and agency employment. In the scope of introduction of the particular flexible forms of employment this thesis in detail deals with the Czech law regulation of these forms of employment and follows up their benefits and drawbacks to the parties of the before mentioned agreements. The thesis briefly mentions some legal issues besides the labor law, especially the issues from fields of the social security law and the tax law.

Le mémoire de maîtrise présente la dynamique de rotor d’une microturbine à gaz à configuration renversée permettant l’intégration de pales en céramique. Cette configuration permet d’utiliser des pales de turbine complètement en céramique car elles sont retenues en compression de l’extérieur par un anneau en composite qui est en rotation. Par contre, la configuration renversée nécessite une nouvelle conception de moyeu de turbine. En effet, l’anneau en composite est loin de l'axe de rotation. Par conséquent, il se dilate beaucoup dus aux efforts centrifuges ce qui entraîne un grand déplacement des pales. L’idée est donc de faire un moyeu flexible qui vient suivre le déplacement des pales pour appliquer une pression en dessous de ceux-ci, afin de les tenir en place par friction. La dynamique de rotor avec moyeu flexible est très peu documentée dans la littérature. Le projet de recherche consiste en la compréhension de la dynamique d’un moyeu flexible pour cibler les paramètres intervenant dans la vibration d’une turbine renversée. La recherche se fera via la conception d’un prototype permettant d’étudier l’effet de la flexibilité pour un concept donné. L’analyse de dynamique de rotor avec moyeu flexible est faite avec un modèle par éléments finis linéaire. Malgré le fait que des non-linéarités peuvent provenir des roulements à billes supportés par des films amortisseurs, un type de roulements couramment utilisé pour supporter des turbocompresseurs, il est démontré qu’un modèle linéarisé capte plutôt bien les tendances mesurées. Le but de ce projet est de déceler les paramètres problématiques d’un moyeu flexible et de découvrir les paramètres permettant une bonne dynamique.

A dissertation submitted to the Faculty of Engineering, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Science in Engineering. / The requirement of the project was to design an automatic storage and retrieval system (AS/RS) to be incorporated into a flexible manufacturing cell (FMC) at the University of the Witwatersrand. This flexible manufacturing cell currently being developed in the Industrial engineering department consists of a CNC milling machine and a CNC turning centre supported by an automated materials handling system, and an integrated computer control system. The automated materials handling system consists of a loop conveyor, parts transfer device, tool changing robot and the AS/RS. All the devices of the materials handling system have been constructed from low cost items readily available or alternatively have been manufactured at the University. The research philosophy adopted was to produce a low cost FMC, using local technology and expertise, to produce a system that is both economically feasible and relatively simple to implement. The AS/IRS is computer controlled consisting of three axis, driven by direct current motors. The AS/RS has a storage matrix of sixteen pallets (four by four) and is able to operate autonomously. The controlling software was written in turbo Pascal and designed to allow interface with the other material handling devices. The software allows for future incorporation of scheduling rules such as first in first out, shortest operating time or a schedule desired by the user. The AS/RS also allows the system to generate managerial reports on the status of the system as well as feedback to the FMC supervisory computer. The design was carried out with the same philosophy used In the FMC i.e, to use low cost items to provide an economically feasible design that is both flexible yet simple to incorporate within a FMC. In conclusion the AS/RS performs the required pick and place function with sufficient accuracy to ensure that parts are correctly positioned. The controlling program of the AS/RS functions correctly in terms of controlling the AS/RS. The AS/RS is fully autonomous in all operations. The AS/RS has the following specifications : Value Units Accuracy 3.67 mm Repeatability 7.2 mm Resolution 0.00977 mm Average pick & place time 41.6 s X Axis travel 1000 mm Y Axis travel 640 mm Z Axis travel 420 mm Lifting capacity 20 N Gripping force 10 N Degrees of freedom 3 The design can be further improved by using stepper motors instead of direct current motors to provide a finer control in terms of velocity and position accuracy. A!though the stepper motors need to have the same price for performance characteristics. / AC 2018

In this thesis we have presented a mathematical model of a scheduling problem which arises in the Brewing Industry. We have implemented two different types of global optimization algorithms to find the global minimum of the problem. Several instances of the scheduling problem are considered and the results thereof are presented. The results show that significant savings can be made if the global optimization techniques are used in brewery Industry.

Wearables for health monitoring are rapidly advancing as evidenced by the number of wearable products on the market. More recently, the US Food and Drug Administration approved the Apple Watch for heart monitoring, indicating that wearables are going to be a part of our lives sooner than expected. However, wearables are still based on rigid, conventional electronic materials and fabrication procedures. The use of flexible conducting materials fabricated on flexible substrates allows for more comprehensive health monitoring because of the seamless integration and conformability of such devices with the human skin. Many materials can be used to fabricate flexible electronics such as thin metals, liquid metals, conducting polymers, and 1D and 2D materials. Ti3C2 MXene is a promising 2D material that shows flexibility as well as desirable electronic properties. Ti3C2 MXene is easily processable in aqueous solutions and can be an excellent functional ink for inkjet printing. Here we report the fabrication and the properties of Ti3C2 MXene films inkjet-printed from aqueous dispersions with a nonionic surfactant. The films are uniform and formed with only a few layers on glass and tattoo paper. The MXene films printed on tattoo are used to record ECG signals with comparable signal-to-noise ratio to commercial Ag/AgCl electrodes despite the absence of gels to lower skin-contact impedance. Due to their high charge storage capacity and mixed (ionic and electronic) conductivity, inkjet-printed MXene films open up a new avenue for applications beyond health monitoring.

L’algèbre de Witt a été intensivement étudiée. Elle est présente dans de nombreux domaines des Mathématiques. Cette thèse est l’étude de deux généralisations de l’algèbre de Witt: les algèbres de type Witt et les algèbres de Krichever-Novikov. Dans une première partie on s’intéresse aux structures Lie-admissibles sur les algèbres de type Witt. On donne toutes les structures troisième-puissance associatives et flexibles Lie-admissibles sur ces algèbres. De plus, on étudie les formes symplectiques qui induisent un produit symétrique gauche. Dans une seconde partie on étudie les algèbres automorphes. Partant d’une surface de Riemann compacte quelconque, on considère l’action d’un sous-groupe fini du groupe des automorphismes de la surface sur des algèbres d’origines géométriques comme les algèbres de Krichever-Novikov. Plus précisément nous faisons le lien entre la sous-algèbre des éléments invariants sur la surface et l’algèbre sur la surface quotient. La structure presque-gradue des algèbres de Krichever-Novikov induit une presque-graduation sur ces sous-algèbres de certaines algèbres de Krichever- Novikov / The Witt algebra has been intensively studied and arise in many research fields in Mathematics. We are interested in two generalizations of the Witt algebra: the Witt type algebras and the Krichever-Novikov algebras. In a first part we study the problem of finding Lie-admissible structures on Witt type algebras. We give all third-power associative Lie-admissible structures and flexible Lie-admissible structures on these algebras. Moreover we study the symplectic forms which induce a graded left-symmetric product. In the second part of the thesis we study the automorphic algebras. Starting from arbitrary compact Riemann surfaces we consider the action of finite subgroups of the automorphism group of the surface on certain geometrically defined Lie algebras as the Krichever-Novikov type algebras. More precisely, we relate for G a finite subgroup of automorphism acting on the Riemann surface, the invariance subalgebras living on the surface to the algebras on the quotient surface under the group action. The almost-graded Krichever-Novikov algebras structure on the quotient gives in this way a subalgebra of a certain Krichever-Novikov algebra (with almost-grading) on the original Riemann surface

Les robots manipulateurs sont généralement des machines rigides, conçues pour que leurflexibilité ne perturbe pas leurs mouvements. En effet, des flexibilités mécaniques importantesdans la structure d’un système introduisent des degrés de liberté supplémentaires dont le comportementest complexe et difficile à maîtriser. Cependant, la réduction de la masse d’un systèmeest bénéfique du point de vue des coûts, de la performance énergétique, de la sécurité et des performancesdynamiques. Afin de faciliter l’accès aux nombreux avantages d’une structure légèremalgré la présence de fortes flexibilités, cette thèse porte sur la modélisation, la conception et lacommande de robots manipulateurs flexibles. Elle est motivée par le projet YAKA, dont l’applicationest le lancement et la récupération de drones à voilure fixe depuis un navire faisant route.Cette application nécessite une importante dynamique sur un vaste espace de travail, bien au-delàdes spécifications des robots rigides classiques. Les outils de modélisation, de conception et decommande proposés prennent en compte la flexibilité des segments et des articulations, pour unnombre quelconque de degrés de liberté et de segments flexibles. Le modèle dynamique flexibleest obtenu par le formalisme de Lagrange, les poutres flexibles sont représentées par le modèled’Euler-Bernoulli. Le schéma de commande proposé se décompose en une inversion de modèledynamique rigide et un bloc de précommande par Input Shaping adapté aux robots manipulateursflexibles. Les outils de conception proposés permettent de baser le processus de conceptionsur des performances prédites du système complet muni de ses actionneurs et de son contrôleuravec une simulation réaliste. Les validations expérimentales effectuées sur le robot YAKA permettentde valider la pertinence de la démarche suivie. Les résultats du projet YAKA confirment lafaisabilité de la mise en oeuvre d’un robot flexible de grande envergure et à forte dynamique dansun contexte industriel, en particulier pour le lancement et la récupération d’un drone à voilurefixe depuis un navire faisant route. / Robot manipulators are generally stiff machines, designed in a way that flexibility does not affecttheir movements. Indeed, significant flexibility introduces additional degrees of freedom witha complex behavior. However, reducing the mass of a system allows for costs, performance, andsafety improvements. In order to allow those benefits despite important flexibility, this thesis focuseson modeling, design and control of flexible robot manipulators. It is motivated by the YAKAproject, which aims at developing a robot to launch and recover fixed wing UAVs from a movingship. It implies reaching very high dynamics on a large workspace, way beyond the specificationsof common rigid robots. The proposed tools for modeling, design and control allow for taking intoaccount both joint and link flexibility, for any number of degrees of freedom and flexible links.The elastodynamic model is obtained with Lagrange principle, each flexible link being representedwith one ormany Euler-Bernouilli beams. The proposed control scheme uses a nonlinear rigiddynamic inversion and extends classical Input Shaping techniques to flexible robot manipulators.The proposed design tools allow for performance prediction of the system including its actuatorsand controllers thanks to a realistic simulation. Experiments conducted with the YAKA robot validatedthe proposed approach. The results of the YAKA project confirmed the feasibility of usinga large scale, highly dynamic flexible robot in an industrial context, in particular for UAVs launchand recovery operations from amoving ship.