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The study investigated the relationship between design and flexibility. Proposals by designers on how to incorporate the ability of buildings to accommodate changes in the requirements of the activities to be housed in buildings over time has led to a diversity of ideas regarding the relationship between suggested design variables and the achieved flexibility. Though a number of studies have been made on specific organisations and buildings, there has been no overall investigation of the general relationship between design and flexibility. To investigate this relationship it was necessary to: 1. Propose a system of measurement by which the extent of incorporation of the design variables in design proposals could be assessed (Chapters II and III). 2. Propose a system of measurement by which the extent of flexibility of buildings in use could be assessed (Chapter IV). 3. Assess the extent of flexibility achieved by the incorporation of design variables in design proposals by a study of actual buildings in use (Chapters V, VI, VII, and VIII). The study has largely achieved these objectives. It provided methods to enable objective comparison to be made between alternative design proposals in terms of the incorporation of design variables. It provided methods to enable objective comparison to be made between buildings in terms of their flexibility in use. It became apparent that the flexibility of buildings in use was related to only certain aspects of design variables or even to only certain parts of buildings. The study demonstrated that the flexibility of buildings in use is largely predictable from knowledge about their design. It showed that current ideas on flexible designs contain many factors that are redundant to flexibility. It recommends that future proposals of designing for flexibility need to be more refined than those at the present and that will enhance the effectiveness of manipulating the potential flexibility of buildings at the design stage. The main area of further research to emerge was concerned with the operationalisation of other design variables and their testing in various building types utilising the methods defined in this study.

Bjälklag av förspända håldäckselement (HD/F) är en kostnadseffektiv lösning för byggnader med stora spännvidder där öppen planlösning eftersträvas. Den ursprungliga konstruktionen för byggnader bestod av HD/F-element och väggar som upplag. Senare blev användning av balkar som upplag allt vanligare lösning. Balkar kallas i det fallet för flexibla upplag. Den här konstruktionslösningen i sig medför sämre bärförmåga hos HD/F-element eftersom balken deformeras vid belastning, och på grund av samverkan mellan balk och HD/F-element uppstår tillkommande spänningar i håldäckselement.   Det här arbetet hade som syfte att undersöka på vilka sätt försämrad bärförmåga hos HD/F-element tas hänsyn till och hur det kan tillämpas vid dimensionering. Detta resulterade i ett beräkningexempel enligt en av de olika beräkningsmodeller som finns. I beräkningasexemplet behandlas bjälklag i ett parkeringshus, och resultatet visar att bjälklaget håller för belastningen med hänsyn till flexibla upplag. / Floor structures constructed by using prestressed precast hollow-core slabs is costeffective solution for buildings that require long span floors. Nowadays the most common design for this type of floors consists of HC slabs supported on beams. In this case beams are called flexible supports because of deflection in the beams. These deflections cause addition stresses in the HC slabs that has to be taken into accout. The purpose of this study was to find out which calculation models exist and how they can be used in design process. As s result of project a calculation example is presented in this report which describes one of possible calculation models.

The application of Flexible Manufacturing Systems (FMSs) has an effect in competitiveness, not only of individual companies but of those countries whose manufactured exports play a significant part in their economy (Hartley, 1984). However, the increasing use of FM Ss to effectively provide customers with diversified products has created a significant set of operational challenges for managers (Mahmoodi et al., 1999). In more recent years therefore, there has been a concentration of effort on FMS scheduling without which the benefits of an FMS cannot be realized. The objective of the reported research is to investigate and extend the contribution which can be made to the FMS scheduling problem through the implementation of computer-based experiments that consider real-time situations.

Ce travail s'inscrit dans le cadre des études sur les moyens d'accéder à une forme d'intelligence ambiante. Il porte sur la réalisation par impression jet d'encre de composants micro-électronique à base de nanotube de carbone sur substrat souple.Dans un premier temps nous avons travaillé sur la mise au point de la technique d'impression jet d'encre. Des études portant sur l'influence de paramètres sur le profil des motifs imprimés ont été réalisées ( distance intergoutte, température du substrat, tension d'éjection, …). La seconde partie de cette thèse porte sur les moyens de réalisation de fines couches de nanotubes de carbone sur substrat souple. Deux méthodes ont été étudiées plus particulièrement, la méthode de dépôt par filtration/report ainsi que la méthode de dépôt assisté par APTS. La méthode par filtration/report se révèle en particulier prometteuse puisqu'elle permet rapidement d'obtenir une couche de 10 nanotubes/μm² pour une épaisseur d'un nanotube.Finalement les connaissances issues de la première partie ont été mises en application pour réaliser des composants simples par impression tels que lignes coplanaires, antennes, capacités et autre. / This work is part of studies on how to reach a form of ambient intelligence. It focuses on the realization of micro-electronics devices based on carbon nanotube on a flexible substrate and by inkjet printing.In a first part we worked on the development of the inkjet printing technique. Studies on the influence of parameters on the profile of a printed patterns have been performed (drop spacing, substrate temperature, firing voltage, ...).The second part of this thesis focuses on how to achieve thin layers of carbon nanotubes on flexible substrate. Two methods have been studied, the method of deposition by filtering/transfert report and the method of APTS assisted deposition. The filtering/transfert method is proving particularly promising since it allows to quickly obtain a layer of 10 nanotubes/ microns square with a thickness of one nanotube. Finally the knowledge from the first part were used to make simple printed components such as coplanar waveguide, antennas, capacitor and others.

Le développement de nombreuses applications nomades, souples, déformables et sur de larges surfaces nécessite la réalisation de circuits mécaniquement flexibles, intégrant des capacités d‘interaction avec l‘environnement, de communication et de traitement de signal. Une part importante de ces applications provient actuellement de l‘industrie de l‘électronique organique, ou intègre des films semiconducteurs à forte mobilité sur des substrats plastiques afin d‘atteindre de meilleures performances. La combinaison de hautes performances électroniques (ondes millimétriques, faible bruit), et d‘une bonne flexibilité mécanique avec la stabilité des propriétés électroniques lors de déformations représente un des grands défis de l‘électronique future. Lors de ces travaux, une procédure d‘amincissement puis de transfert sur un film plastique des composants CMOS initiallement réalisés conventionnellement sur des tranches SOI (silicium sur isolant) a été développée. Cette solution permet la réalisation de transistors MOS flexibles et performants : possédant des fréquences caractéristiques fT/fmax de 150/160GHz et des performances en bruit NFmin/Ga de 0.57/17.8dB. De plus, positionner le plan neutre de l‘ensemble au niveau de la couche active du transistor permet de réduire les variations de propriétés électroniques à 5% même lors de déformations agressives. La réalisation de composants souples, performants et stable a ainsi été démontrée. / The ability to realize flexible circuits integrating sensing, signal processing, and communicating capabilities is of central importance for the development of numerous nomadic applications requiring foldable, stretchable and large area electronics. A large number of these applications currently rely on organic electronics, or integrate high mobility active films on plastic foils to provide higher performance. A key challenge is however to combine high electrical performance (i.e. millimeter wave, low noise electronics), with the mechanical flexibility required to conform to curvilinear surfaces, in addition to high stability of these electrical performance upon deformation. In this work, a solution has been developed, based on thinning and transfer onto plastic foil of high frequency (HF) CMOS devices initially processed on conventional silicon-on-insulator (SOI) wafers. This transfer process first enables the fabrication of high performance electronics on plastic, with n-MOSFETs featuring characteristic frequencies fT/fmax as high as 150/160GHz in addition to low noise potentialities: NFmin/Ga of 0.57/17.8dB. Secondly, by locating the neutral plane of the flexible system in its active layer, the relative variation of these high frequency figures-of-merit can be limited to 5% even after aggressive bending, demonstrating flexibility, high performance and stability.

Acute respiratory distress syndrome (ARDS) and infant respiratory distress syndrome (IRDS) are severe pulmonary syndromes affecting approximately 190,000 in the United States with a mortality rate of 40%. During ARDS, hypoxemia can follow, which requires mechanical ventilation. This assisted ventilation can injure the lung by inducing large mechanical stresses from an air-liquid interface propagating through occlusion, and exposing the vessel wall to large mechanical stress gradients. In this study we investigate airway reopening scenarios by creating a model of terminal pulmonary airways using flexible tubing with monolayer coverage of lung epithelial cells. Specifically, we attempt to find a relationship between the state of collapse of a channel and the stress the cells undergo during the reopening event. This study is the first demonstration of an experimental tube with a tube law approximately physiological range. Our results indicated that in collapsed channels, as the velocity of reopening increases, the amount of damage to cells increases. This indicates flexibility causes an increase in cell damage which agrees with the stimulus-response behavior from prior studies. However, in fully-inflated channels, we see transitional behavior between flexible and rigid models. This research is a good starting point to investigate recruitment-derecruitment events in flexible channels, which could give a better representation of the mechanisms that cause cell damage in cases of ARDS and VILI. / 1 / Michael C Harrison

L'électronique flexible est devenue un sujet au cœur des recherches actuelles. Dans ce but, plusieurs matériaux ont été utilisés tels que le PEN, PET ou le polyimide (PI). Ces matériaux présentent une bonne flexibilité et une compatibilité chimique avec les différents procédés utilisés en microélectronique, mais souffrent d'une faible conductivité thermique, menant à une réduction des puissances de travail des composants électroniques transférés sur de tels substrats, comparé à des substrats rigides plus classiques tels que le Silicium. Plusieurs pistes ont été investiguées pour contourner ce problème, et l'une des solutions consiste à remplir la matrice du polymère ou PI avec des nanomatériaux. Dans ce sens nous avons utilisé des structures 3D de graphène et de nitrure de bore hexagonal sous forme de mousse afin de remplir la matrice d'un PI. Nous expliquerons en détail comment nous avons obtenu un nouveau substrat flexible avec des propriétés thermiques améliorées. / A major challenge is to find a way to grow those materials in order to achieve an easy and economically attractive way to produce large area of those materials with a good quality. Another challenge is to transfer those materials on substrate compatible with electronics (mainly SiO2). We will focus the first part of our work on investigation of the growth conditions required to produce large area graphene and h-BN of good quality and their transfer on SiO2. Flexible electronics has become an important field of research for many applications, such as flexible batteries. In this goal, several materials have been used such as PEN, PET or polyimide (PI). All these materials present a good flexibility and a chemical compatibility with microelectronics process but they suffer from poor thermal conductivity, leading to lower utilization of power of devices deposited compared to classic microelectronic substrate such as SiO2. Several way have been recently investigated to bypass this problem and a good solution is to fill the matrix of the polymer or polyimide with nanomaterials or nanofillers. We choose to use graphene and h-BN as the filler in a 3D shape: a foam of graphene or h-BN as the nanofiller and we chose a PI as the matrix. In the second part, we will explain in details how we achieve novel flexible substrates with enhanced thermal properties. We succeed in producing polycrystalline graphene on copper with quite a good quality, fully covering the metallic substrate with a size of 2x2cm. We tried to grow monocrystalline graphene using standard CVD and achieved hexagonal single crystals of 30µm, which is quite small compared to other methods used in literature. We synthetized polycrystalline h-BN using copper as a catalyst and ammonia borane as the precursor with a size of 6x2cm with a good homogeneity on all available substrate. We were able to transfer both graphene an h-BN on Si02 substrate using both classical wet transfer and bubbling transfer, leading to a fastest transfer and resulting on clean transfer of our materials, free of cracks, bubbles and resist residues. We succeed in producing both 3D graphene and 3D h-BN as foam using a Nickel foam as the catalyst, resulting in multilayer graphene and h-BN with a good quality. We produced new flexible and thermal efficient substrates using these foams as a filler in a matrix of PI, already commonly used as a classical flexible substrate for microelectronics. We developed two generations of substrates. We found similar mechanical properties and thermal stability as the commercial Kapton. We deposited thermistors on the surface in order to study the thermal dissipation of our samples. We improved the maximum power applied on the thermistors up to 100% before breakdown.

This paper provides insights into the problems of designing a robot with joint and link flexibility. The relationship between the deflection of the robot under gravity is correlated with the fundamental frequency of vibration. We consider different types of link geometry and evaluate the flexibility potential of different materials. Some general conclusions and guidelines for constructing a flexible robot are given.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 47-52). Also available in electronic version.