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Les convertisseurs électroniques de puissance sont aujourd’hui très largement utilisés dans tous les domaines de la conversion d’énergie. Ils sont des outils désormais incontournables de tout processus de gestion des transferts de l’énergie électriques depuis les puissances les plus faibles (quelques mW) jusqu’à plusieurs dizaines voire centaines de MW. Le domaine de l’électronique de puissance subit actuellement une double mutation liée aux possibilités offertes par les technologies d’intégration d’une part et l’arrivée de nouveaux composants à semi-conducteur de puissance de type grand-Gap d’autre part.Dans cette thèse supportée par l’ANR, nous avons étudié et évalué les potentialités associées à l’intégration de composants de puissance traditionnels (Silicium) et à base de matériaux grands Gap (GaN). Nous avons, pour cela, développé des procédés de fabrication destinés à l’intégration de composants GaN à structure latérale et de composants Silicium à structure verticale. Le contexte applicatif de cette thèse est celui de l’accroissement du niveau d’électrification dans les avions de nouvelle génération.Pour les composants grand Gap de type GaN à structure latérale (basse tension), nous avons proposé un nouveau procédé de report sur substrat céramique (DBC) et nous avons démontré que cette solution permettait d’améliorer considérablement la gestion thermique de ces composants. Sur la base de ces structures, nous avons également présenté et évalué des méthodes de modélisation permettant la conception de ces dispositifs. Cette modélisation, utilisant des méthodes numériques de type éléments finis ou des méthodes analytiques, traite de deux aspects de la conception : la prédétermination du comportement thermique et la prédétermination du comportement électrique et CEM (en ce qui concerne les aspects conduits)Pour les composants à structures verticales (haute tension), nous avons démontré la faisabilité technologique d’une solution alternative aux packagings traditionnels (assemblage sur DBC et connexion par fils de Bonding). Le process proposé permet, par enterrement des puces dans le PCB, de réaliser une interconnexion 3D permettant de réduire les inductances parasites de boucle très largement dues aux inductances parasites des fils de Bonding. Ceci a pu être démontré sur un prototype de convertisseur complet. Ce procédé d’enterrement des puces s’avère donc particulièrement adapté dans le cas de composants à commutation très rapide. / Power Electronic converters are now widely used in all areas of energy conversion. They are tools that cannot be ignored in any process of managing electrical energy transfers from the lowest powers levels (a few mW) to several tens or even hundreds of MW. Power electronics technologies are currently undergoing a double mutation linked to the possibilities offered by integration technologies on the one hand and the arrival of new Wide-Band-Gap power semiconductor components on the other hand.In this thesis supported by the French ANR, we studied and evaluated the potentialities associated with the integration of traditional power components (Silicon) as well as those based on Wide-Band-Gap materials (GaN). We have developed new technological processes for the integration of GaN components with a lateral structure and silicon components with a vertical structure. The application context of this thesis is linked to the problematic of increasing the level of electrification in new generation of aircrafts.For Wide-Band Gap GaN type power devices with a lateral structure (low voltage), we proposed a new method of device-attachment to a metalized ceramic substrate (DBC) and we demonstrated that this solution made it possible to considerably improve the thermal management of these components. On the basis of these structures, we also presented and evaluated modeling methods allowing the design of the whole packaging. This modeling, using numerical tools based on finite element method or analytical equations, deals with two aspects of the design: the predetermination of the thermal behavior and the predetermination of the electrical and electromagnetic behavior (with regard to the conducted aspects)For components with vertical structures (high voltage), we have demonstrated the technological feasibility of an alternative solution to traditional packaging (assembly on a DBC substrate and electrical connection by wire bonding process). The proposed process allows, by embedding the power dies in the PCB, to carry out a 3D interconnection making it possible to reduce the parasitic loop inductances mainly linked to the parasitic inductances of the bondwires. This has been demonstrated on a converter prototype. Embedding power devices is thus particularly suitable in the case of components with very fast switching capabilities.

Active packaging systems can offer significant advantages in preventing quality loss in horticultural products through control of microbial and/or physiological activity. By delivering and sustaining volatile active agents at effective levels in a package atmosphere, significant shelf life extension can thus be achieved. Design of these systems is complicated by the number of possible package, product, active agent and carrier combinations that can be employed and the significant interactions that may occur between these components. Mathematical modelling can be used to simplify system design and reduce the number of experimental trials required to achieve optimal active packaging systems. In this study a generalised modelling methodology was developed and validated to facilitate the design of active controlled volatile release packaging systems for horticultural products. The modelling methodology was developed using an example system which comprised tomatoes packed under a modified atmosphere (MA; 5 % (v/v) CO2 and 10 % (v/v) O2) in a LDPE bag with a polymer film sealed sachet containing silica gel pre-saturated with the antifungal agent hexanal. Experimental trials showed that for this system a target sustained hexanal concentration of 40-70 ppm was required. This was shown to be (i) the minimum inhibitory concentration (MIC) for controlling Botrytis cinerea growing on tomatoes stored at 20°C and ~99%RH, (ii) to have only a relatively minor influence on the postharvest quality of tomatoes under these active MA conditions, and (iii) to promote only a small apparent uptake of hexanal from the atmosphere by the tomatoes. The effective hexanal permeabilities of Tyvek , LDPE and OPP sachet films were characterised using the isostatic method and shown to exhibit a dependence on both temperature (10 and 20°C) and concentration (over a range of 0.01-0.22 mol m[superscript -3). Average permeabilities decreased in the order of Tyvek > LDPE > OPP, respectively, at all temperatures at comparable hexanal partial pressures. Hexanal sorption isotherms for silica gel at both 10 and 20ºC were determined using the gravimetric method and were reasonably well described by the Langmuir equation. The equilibrium amount adsorbed was significantly reduced at the higher temperature but the pre-adsorption of water vapour on hexanal uptake on silica gel showed no uniform trend on the sorption characteristics suggesting that multicomponent sorption is complex. A generalised modelling methodology was developed through conceptualising key mass transfer processes involved in these active MA packaging systems. Quantitative methods for deciding the relative importance of each process were established together with guidelines for when simplifying assumptions could be made. This information was formalised into a decision tree to allow appropriate assumptions to be made in model formulation without unacceptable loss of model accuracy. Methods to develop generalised equations from these assumptions to describe changes in the sachet, package headspace and outer bag film with respect to an active agent and MA gases were then identified. The mathematical modelling methodology was applied to the example hexanal release active MAP tomato packaging system. For these systems there was a high initial peak in package headspace concentration during the first 24 h which declined to a quasi steadystate concentration over a period of days. The quasi steady-state headspace concentrations were generally in the MIC range and were well predicted by the model. Interactions between water vapour and silica gel may have been responsible for the relatively higher hexanal concentration at the onset of release from the Tyvek sachet (a highly porous material). However the influence of water vapour (>95% RH in the MA bag containing tomatoes) during the quasi steady-state period appeared to be insignificant for all sachet films. The model was successfully applied to a range of packaging configurations and storage temperatures. A lack of fit was evident between model predictions and experimental trials during the initial (unsteady-state) stages of the release pattern for both headspace vapour concentrations and adsorbed mass on the silica gel. These differences were attributed to (i) model input uncertainties, chiefly with regard to the estimated coefficients of both the Langmuir isotherm equation and film permeability, and (ii) overestimated effective permeability values predicted by extrapolation of the concentration dependence of film permeability beyond the conditions for which the permeability was measured. These results suggest improved models for the effective permeabilities of the films, quantified under a range of vapour concentrations and concentration gradients, are required for better describing fluxes across the sachet film. Despite these limitations, the model did describe the general release pattern. The model was then used to pose a range of ‘what-if’ scenarios investigating the release patterns predicted for different active packaging designs. This analysis gave useful insights into how sorption isotherm shape and package/sachet design parameters can be manipulated to achieve different volatile release platforms. The work clearly demonstrated the importance of accurate data for permeability of volatile compounds through polymer films and for sorption of the active agent on the carrier phase. More work on characterising these systems is recommended to further improve modelbased design methods for active MAP systems. Overall the generalised methodology developed can be confidently adopted for constructing a mathematical model that provides sufficient accuracy and simplicity to be implemented for designing active packaging systems for horticultural and food products.

The topic of the thesis is Proposal of Business Expansion - Building-up of Packaging Unit. The proposal is based on the analysis of the current production capacity and production equipment, and on the analysis of money management and ascertained shortcomings. On the basis of the carried out analysis a proposal for building-up of a new production unit and a recommendation on purchase of new machine equipment has been made. A calculation of investment costs is a part of the proposal.

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This thesis aims to identify and explain how, through the consumption of the wireless as a modern consumer durable, modernism was brought to society. To understand this process, the study will map how social change during the period responded to wider intellectual and aesthetic currents and trends but was driven by emergent commercial, cultural and political economies of a newly mediated society. Furthermore, it seeks to establish that this happened not as a result of social engineering through model housing schemes but as a result of consumer-led demand. This investigation considers how, as part of that newly mediated social environment, the wireless developed following its arrival on the domestic market without having adopted a single stylistic form. It addresses how that form, both stylistically and technically, evolved over a relatively short period to address the economic and cultural requirements and expectations of a new electrically powered domestic entertainment technology. In so doing, a discourse will be established considering these expectations and requirements related to how the wireless in Britain adopted and adapted the Modernist design idiom. It will further consider how the language of Modernism was propagated as the accepted version of what a radio could or should look like, so developing the modernist paradigm in a broader sense. To gain an appreciation of this it is necessary to understand the contemporary public conception of what the modern was in a more general sense. To decipher this public perception of modernity the project aims to extrapolate that public conception through examining other popular forms and products. Although this suggests that Radio was not alone in adopting the language of the moderne, as a product it is notable for its widespread commercial success and as such can be identified as a significant carrier of the coded message of what was modern. Design historians such as Yagou and Forty have attempted to incorporate radio into various strands of historical perception but the typologies they have devised to describe and understand wireless fall short in addressing the relationship between modernity and the wireless and instead see the wireless in terms of being an independent consumer product, a quasi-scientific instrument or else a furnishing form, rather than creating categories which accommodate the wireless and its position as a design type in its own right. To overcome this shortcoming a strand of this thesis seeks to argue that the wireless was itself a proto-modernist device during the early years of market expansion. That device then developed along a natural stylistic course embracing contemporary decorative ideas. By assessing the response of radio manufacturers to the socio-economic conditions of their market, this study has highlighted how through producing a product which addressed contemporary ideas of glamour, ease of use and functionality, the wireless entered a wide range of homes during the 1920s and 1930s. For the public, the immediate appeal of the wireless was that it provided access to the international experience of listening in while simultaneously it provided a template for the consumer to base their understanding of the modern World, both in its mediated form and stylistic appearance. This thesis seeks to demonstrate that during the period 1925 to 1939, the wireless established itself as an unashamedly modern device which appealed to a broad socio economic cross section of the public. By consuming the wireless, the British public accepted a significant technological and stylistic aspect of modernity into their homes. This was achieved despite the privations of the era because of the perceived desirability of wireless broadcasts and the perception of listening in as a popular leisure activity. As a result of that consumer demand, the British public was given access to a range of stylistic versions of modernity through the design of radio cabinetry. These modern styles were readily consumed throughout the social spectrum in preference to historicist alternatives. This demonstrates that the wireless was instrumental in introducing the modernist aesthetic to the British domestic environment.

This dissertation focuses on high-performance LC-tank CMOS VCO design at 2 GHz. The high-Q inductors are realized using wiring metal lines in advanced packages. Those inductors are used in the resonator of the VCO to achieve low phase noise, low power consumption, and a wide frequency tuning range. In this dissertation, a fine-pitch ball-grid array (FBGA) package, a multichip module (MCM)-L package, and a wafer-level package (WLP) are incorporated to realize the high-Q inductor. The Q-factors of inductors embedded in packages are compared to those of inductors monolithically integrated on Si and GaAs substrates. All the inductors are modeled with a physical, simple, equivalent two-port model for the VCO design as well as for phase noise analysis. The losses in an LC-tank are analyzed from the phase noise perspective. For the implementation of VCOs, the effects of the interconnection between the embedded inductor and the VCO circuit are investigated. The VCO using the on-chip inductors is designed as a reference. The performance of VCOs using the embedded inductor in a FBGA and a WLP is compared with that of a VCO using the on-chip inductor. The VCO design is optimized from the high-Q perspective to enhance performance. Through this optimization, less phase noise, lower power consumption, and a wider frequency tuning range are obtained simultaneously.

Seit 2015 arbeitet das Fraunhofer IVV, Dresden intensiv mit interdisziplinären Forschergruppen aus Maschinenbauern, Mechatronikern, Psychologen und Designern an der Entwicklung eines selbstlernendes Bediener-Assistenzsystems. Von Beginn an wird das Team außerdem von einem industriellen Beraterkreis aus Verbänden, Maschinenbetreibern und -herstellern unterstützt. Dadurch wird die Forschung und Entwicklung eng an den Bedarfen der potentiellen Nutzer ausgerichtet. Gleichzeitig erhalten unsere Partner die Möglichkeit, ihre eigenen Entwicklungen und Prozesse zu hinterfragen und sich mit kompetenten Experten über bestimmte Herausforderungen auszutauschen. In dieser Kooperation hat sich das jährliche VVD-Anwenderforum zum zentralen Baustein entwickelt. Am 10. Oktober 2019 findet nun unser 3. VVD-Anwenderforum „Bediener-Assistenzsysteme“ in Dresden statt. Dazu möchten wir Sie recht herzlich einladen. Zusätzlich vom VVD-Anwenderforum bieten wir am 9. Oktober ein Workshop „Einstieg in Machine Learning“ statt. In diesem Workshop stellen wir das wichtigste Wording, die grundlegende Mathematik, die Möglichkeiten und Grenzen vor. Damit wollen wir die Teilnehmenden in die Lage versetzen, Ideen für eigene Anwendungsmöglichkeiten zu entwickeln und sich mit Fachexperten über Zielstellungen auszutauschen.:1. Andre Schult (Fraunhofer IVV Dresden): Aktueller Stand SAM und Vorstellung der Pilotprojekte 2. Dr. Romy Müller (TU Dresden, Professur für Ingenieurpsychologie und angewandte Kognitionsforschung): Psychologische Aspekte der Mensch-Maschine-Interaktion 3. Moritz Schroth (Fraunhofer IVV Dresden): Aktuelle Forschungsprojekte für die Industrie4.0 – opticSAM 4. Patrick Binzer (Multivac Sepp Haggenmüller SE & Co. KG): Automatisierte Maschinenkonfigurationen aus Kundensicht 5. Dr. Lukas Oehm (Fraunhofer IVV Dresden): Vorstellung geplanter Forschungsvorhaben Fraunhofer IVV