The term Nanoceramics is well known in the ceramic field for at least two decades. In this project a detailed study was performed on the synthesis of α-alumina nanopowders. High solids content nanoalumina suspensions were prepared and used to form green bodies using both wet and dry forming routes. The green bodies were then sintered using both conventional single and two-step sintering approaches. Synthesis: Two different synthesis methods, viz. precipitation and hydrothermal treatment, were used to synthesize fine α-alumina powders from aluminium chloride, ammonia solution and TEAH (Tetraethyl ammonium hydroxide). XRD, TEM and FEG-SEM were used to characterise the powders produced. The presence of commercial α-alumina powder as seed particles did not affect the transformation to α-alumina phase during the hydrothermal treatment at 220˚C in either basic or acidic environments. The results obtained from the precipitation route showed that the combined effect of adding α-alumina seeds and surfactants to the precursor solution could lower the transformation temperature of α-alumina from about 1200˚C for unseeded samples to 800˚C, as well as reducing the level of agglomeration in the alumina powders. The difference in transformation temperature mainly resulted from the nucleation process by the α-alumina seeds, which enhanced the θ → α transformation kinetics. The lower level of agglomeration present in the final powders could be due to the surface modifying role of the surfactants preventing the particles from growing together during the synthesis process. By introducing a further high-temperature step for a very short duration (1 minute) to the low-temperature heat treatment route (800˚C/12 h), the unseeded sample with added surfactant transformed into pure α-alumina phase. The newly-added step was shown to be an in-situ seeding step, followed by a conventional nucleation and growth process. The best final powder was compared with a commercial α-alumina nanopowder. Processing of alumina ceramics: The effect of low-molecular weight ammonium dispersants including Dispex-A40, Darvan-C and Dolapix-CE64, on high solids content nanoalumina suspensions was investigated. The nanosuspension prepared using the most suitable dispersant, Dolapix-CE64, was slip cast into ~53% dense, very homogeneous green bodies. This nanosuspension was also spray freeze dried into crushable granules using Freon as a foaming agent. Green compacts with density of ~53.5% were then formed by dry pressing the 2 vol% Freon-added spray freeze dried granules at 40 MPa. Both slip cast and die pressed green bodies were sintered using conventional single-step and two-step routes followed by characterising the density and grain size measurement of final dense compacts. The results have been compared with that of a submicron alumina ceramic prepared using a commercial α-alumina suspension. Highly dense alumina with an average grain size of ~0.6 μm was fabricated by means of spark plasma sintering at 1200˚C. The application of 500 MPa allowed achieving almost fully dense alumina at temperature as low as 1200˚C for 30 minutes with no significant grain growth.

La tesi si occupa della rappresentanza degli interessi imprenditoriali in Italia, con un focus particolare sulle crisi 1989-1994 e 2007-2014, analizzando il mondo delle associazioni imprenditoriali private e delle Camere di commercio. / This work is about the representation of entrepreneurs interests in Italy, with a specific focus on 1989-1994 and 2007-2014 crisis, analyzing business associations and Chambers of commerce as institutions.

Offshore oil and gas exploitation is principally conducted using dry or wet tree systems, otherwise called the subsea Xmas tree system. Due to the shift to deeper waters, subsea production system (SPS) has come to be a preferred technology with attendant economic benefits. At the centre of the SPS is the subsea control module (SCM), responsible for the proper functioning and monitoring of the entire system. With increasing search for hydrocarbons in deep and ultra-deepwaters, the SCM system faces important environmental, safety and reliability challenges and little research has been done in this area. Analysis of the SCM reliability then becomes very fundamental due to the huge cost associated with failure. Several tools are available for this analysis, but the FMECA stands out due to its ability to not only provide failure data, but also showcase the system’s failure modes and mechanisms associated with the subsystems and components being evaluated. However, the technique has been heavily challenged in various literatures for several reasons. To close this gap, a novel multi-criteria approach is developed for the analysis and ranking of the SCM failures modes. This research specifically focusses on subsea tree-mounted electro-hydraulic (E-H) SCM responsible for the underwater control of oil and gas production. A risk identification of the subsea control module is conducted using industry experts. This is followed by a comprehensive component based FMECA analysis of the SCM conducted with the conventional RPN technique, which reveals the most critical failure modes for the SCM. A novel framework is developed using multi-criteria fuzzy TOPSIS methodology and applied to the most critical failure modes obtained from the FMECA evaluation using unconventional parameters. Finally, a validation of these results is performed using a stochastic input evaluation and SCM failure data obtained from the offshore industry standard reliability database, OREDA.

A real-time simulator (RTS) with digital and analog input/output modules is used to conduct hardware-in-the-loop simulations to evaluate performance of power system equipment such as protective relays by exposing the equipment to the simulated realistic operating conditions. This work investigates the use of RTS to test relays with single-pole-switching (SPS) feature. Single-pole switching can cause misoperations due to fault arc during reclosing of the breakers. Through this investigation, a test procedure appropriate for the testing SPS relays has been developed. The test procedure includes power system modeling for real time simulation, relay test setup, and test plan. HYPERSIM real-time simulator was used to model an actual power system. Transmission lines, three-winding transformers, and induction motor were modeled with actual parameters. Models for fault arc in HYPERSIM real time simulator were developed. Test set-up for evaluating relay performance and wiring drawings for connecting relay in closed-loop to the simulator were developed.

La ricerca internazionale e nazionale ha messo in luce come la separazione/divorzio risulti essere una transizione familiare complessa, con molteplici conseguenze su diversi aspetti: personali/psicologici, sociali/relazionali, giuridici ed economici. Si assiste da una parte alla rottura del legame di coppia, che implica quindi una riorganizzazione e ridefinizione dei confini – familiari e non -, dall’altra parte vi è la continuità del legame genitoriale con i figli; quest’ultimo risulta essere particolarmente sfidante per i padri, che nella maggioranza dei casi non vivono quotidianamente coi figli. In Italia molti sono i padri che a seguito di tale evento si trovano in una condizione di povertà e che pertanto vivono maggiori difficoltà nell’esercitare il ruolo paterno. La presente ricerca va ad indagare nello specifico i padri che, dopo la separazione/divorzio, vivono una condizione di difficoltà abitativa e che sono accolti in strutture a loro dedicate (progetti di co-housing), con l’obiettivo di sostenerli per quanto riguarda le risorse materiali affinchè possano continuare ad esercitare il ruolo genitoriale. La domanda di ricerca sottesa è volta ad indagare che tipo di riflessività questi padri mettono in campo. Emerge un quadro complesso, di povertà multidimensionale, in cui si intersecano diverse dimensioni: economica, abitativa, lavorativa, personale, relazionale, familiare, genitoriale. / International and national research reveal how separation/divorce are events that can impact dramatically on family life trajectories: parents, children and family networks are involved in such event. It makes necessary to redefine and reorganize not only the daily and the relationships but also the identity of the people: mothers and fathers still remain parents, and they have to redefine and reorganize themselves as parents. In this context, this research will focus on the consequences of father’s lives, relationships and fathering practices after divorce in Italy. Divorced fathers are at risk of social exclusion: they, for instance, use social canteen for meals and co-housing or social projects in order to prevent homelessness. The main research question addressed is about the identity of such fathers who have to redefine and re-organize themselves. Findings suggest that we can observe a multidimensional framework that characterizes these fathers: unstable living and working conditions, economic resources, difficulties with children and poor social relationships. In considering divorce consequences, it is important to include both material and relational well-being after divorce (the structural dimension as well as the cultural and relational dimension), due to prevent the risk that marginalized fathers become “absent” fathers.

Oxide ceramics have been increasingly researched for high temperature thermoelectric (TE) applications. SrTiO3 based materials are promising candidates due to its chemical and thermal stability. In this study, oxide ceramics of composition (1-x)SrTiO3-(x)La1/3NbO3 (0 smaller or equal to x smaller or equal to 0.3) were prepared by single-step solid state sintering in Ar/5%H2 at 1700 K. The density of all the samples prepared was above 90%. All the samples were predominantly single-phase compositions crystallised with a cubic structure in Pm ̅3m space group. The impact of oxygen deficiency, A-site vacancies and mixed oxidation states of Ti3+/Nb4+ on electrical and thermal transport properties was assessed. Optimum TE properties were obtained for x=0.2 (Sr0.8La0.067Ti0.8Nb0.2O(3-delta) = L2), which has 13.4% A-site vacancies. The ZT values improved from 0.2 to 0.27 at 1000 K, with an increase in sintering time from 8 hours to 48 hours, due to increased carrier concentration. Complex interplay of oxygen vacancies and excess donor substitution on A/B-sites of L2 (substituting 5-10% Sr/Ti with La/Nb) exhibited 35% improvement in ZT values, whilst maintaining the A-site vacancies and core-shell structures within grains, which reduced the thermal conductivity by ~50% compared to undoped SrTiO3 samples, due to strong phonon scattering. A facile method to incorporate metallic inclusions (2.5 wt% Fe/Cu) at grain boundaries in L2 ceramics is demonstrated. The modified compositions displayed a maximum ZT of ~0.37 at 1000 K for L2 samples containing metallic inclusions due to increased carrier concentration (5.5 x 10^21 carriers/cm^3) and carrier mobility (2.4 cm^2/(V.s).The addition of graphene/Graphene Oxide (GO) flakes in L2 ceramics has been investigated to improve the electrical conductivity of L2 composites without significantly increasing the thermal conductivity. Spark plasma sintering (SPS) of the composite powders at 1473 K and 50 MPa produced dense samples (>95% relative density) with a homogeneous dispersion of graphene/GO flakes, for loadings smaller or equal to 1.0 wt%. The effect of interaction and distribution of graphene/GO flakes within the ceramics on TE properties is investigated. The composite samples demonstrate anisotropic ZT values, with 20% improvement in the direction normal to the orientation of graphene flakes. A novel sintering method has been proposed which has strong industrial potential. The L2 based composites were sintered in Air at 1700 K (ramp rate: ±300 K/min), whilst samples were covered uniformly. Strong reducing conditions and evolution of secondary phases in the microstructure helped achieve, the very low electrical resistivity of ~3.0 x 10^(-6) ohm.m at room temperature. Secondary phases, sub-micron voids in the grains and A-site vacancies reduced the lattice thermal conductivity (~2.0 W/m.K), comparable to the lowest lattice thermal conductivity achievable (~1.5 W/m.K) at 1000 K and obtain a maximum ZT of 0.4 at 1000 K for L210G-Air/C composites.

Högkänslighet är någonting som under senare år uppmärksammats i media. Kortfattat innebär högkänslighet att individen tar in fler intryck och bearbetar dem på ett djupare plan än andra. Högkänsliga individer kan ha lätt för att känna av sinnesstämningar och blir lätt påverkade av andras känslor. Vid för mycket stimulans blir högkänsliga individer lätt överstimulerade vilket kan leda till att de beter sig på sätt som inte alltid är socialt accepterat. De spenderar mycket tid och energi åt att bearbeta intryck och blir därav lätt utmattade och behöver tid för att skärma av. Den här studien fokuserar främst på det högkänsliga barnet och hur de anpassar sig i en förskolemiljö. Syftet med studien är att undersöka hur pedagoger, upplever att högkänsliga barn anpassar sig i förskolans miljö samt hur pedagogerna bemöter behoven hos barn som är högkänsliga. För att göra studien möjlig har tre forskningsfrågor konstruerats. Studien har undersökt hur pedagoger ser på högkänslighet i sitt yrke, hur de anser att högkänsliga barn anpassar sig i förskolan samt hur de i sin tur bemöter de högkänsliga barnets behov. För att få en övergripande bild om hur pedagogerna ser på högkänslighet har Arons begrepp DOES används för att utsöndra begreppet och därefter landa i en övergripande uppfattning. Studien är baserad på åtta kvalitativa intervjuer med pedagoger som besitter medvetenhet kring begreppet högkänslighet och är yrkesverksamma inom förskolan. Varje intervju har transkriberats och analyserats genom kodning, tematisering och summering där varje enskildintervju bidragit med nya berikade infallsvinklar kring ämnet, det gick även att urskilja gemensamma infallsvinklar som tematiserades och presenterades i uppsatsens resultatkapitel. Ett framträdande resultat av studien var att högkänslighet bör uppmärksammas mer för att i sin tur tidigt kunna identifieras hos barn. Ett annat av intervjuerna framträdande resultat, var att pedagogens bemötande syntes vara betydande för huruvida det högkänsliga barnet anpassar sig i förskolans miljö. Om pedagogens bemötande gick i linje med barnets behov skulle denne ha goda förutsättningar att anpassa sig i en förskolemiljö.

New Zealand is currently the third largest global producer of kiwifruit and thus plays an important role in the international market. Exports of kiwifruit are also of significant horticultural value for New Zealand and in 2007 the kiwifruit industry accounted for export values of NZ$790 million. The global kiwifruit market has experienced substantial changes in recent years and is likely to change significantly in the near future due to developments in production sources, adjustments to trade policy settings and shifts in consumer preferences. The New Zealand kiwifruit industry needs to consider what the impacts of these changes might be so that future strategies can be constructed effectively. Little quantitative modelling has been done in New Zealand to consider the impacts of changes to the global kiwifruit industry. The major contribution of this research was the development and calibration of a kiwifruit industry-specific partial equilibrium trade model. The model was then used to examine the impacts on New Zealand producers of these trade-related changes in the global kiwifruit market. Three relevant scenarios were developed for this purpose. They include a drop in EU demand through the introduction of a stricter Sanitary and Phytosanitary policy, an expansion of the Chinese kiwifruit industry where production is doubled by year 2013 and finally a trade liberalisation scenario where current import tariffs on kiwifruit were removed worldwide. It is clearly observed, through both the Chinese expansion scenario and the trade liberalisation scenario, what a potential impact and future role China has as a world market player. Increased availability of Chinese kiwifruit appears to affect New Zealand producer returns and exported quantities negatively, albeit not as significantly as the EU introduction of an SPS policy. A trade liberalisation scenario, on the other hand, proves to increase New Zealand grower returns significantly for all varieties.

L'objectif de cette thèse a été l'évaluation de deux semi-conducteurs (l'InP :Fe et le SPS :Te) comme matériaux pour les télécommunications optiques aux longueurs d'ondes infrarouges. <br /> D'abord, en ce qui concerne l'InP :Fe: nous avons fait une caractérisation systématique du phénomène d'autofocalisation photoréfractive, prenant en compte les paramètres les plus importants qui intervient dans ce phénomène (température, dopage, intensité du faisceau et de l'éclairage de fond, polarisation du faisceau). Ainsi, nous sommes maintenant capables de contrôler le phénomène d'autofocalisation. En tenant compte également des temps de réponse mesurés et des simulations réalisées, nous croyons que l'interaction de deux faisceaux autofocalisés est possible et maîtrisable sur une échelle de temps de l'ordre de microsecondes. Néanmoins, alors que nous connaissons l'influence des paramètres mis en jeu sur l'autofocalisation, le développement d'un modèle théorique reste indispensable pour une compréhension des mécanismes physiques qui déterminent la dynamique de l'autofocalisation photoréfractive. Nos mesures expérimentales et simulations théoriques ont montré que les modèles existants ne décrivent pas d'une manière satisfaisante les phénomènes observés dans InP :Fe.<br /> En revanche, l'autofocalisation observée dans le SPS :Te est décrite par les modèles "classiques" existants. On peut dire que ce deux matériaux sont complémentaires: alors que dans le SPS :Te l'autofocalisation est plus lente que dans l'InPFe, elle est plus forte et plus facile à maîtriser. Tenant compte de cette remarque, nous croyons que ces deux matériaux trouveront leur place dans de futures applications.

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