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Porous NiTiO3/TiO2heterostructures prepared from the annealing in air of TiO2 : Ni nanoneedle bundles displayed excellent photocatalytic activity toward hydrogen generation.

The final master thesis investigate behavioural patterns of the users of bike-sharing system BIXI in Montreal. A data mining approach is used by applying clustering methods on open data from BIXI, the Government of Canada and the City of Montreal. Hierarchical clustering with Ward and Gower is processed to form clusters using only the BIXI variables at first. Then, because the authors believe that contextual information has a fundamental effect on the user’s behaviour, they investigate the impact of adding such information into the clustering methodology. In the end, a multi-view clustering method is preferred for its quality of preserving the basic characteristics of simpler set of clusters (mixing less variables). Afterwards, local analysis are done over some profiles of the classes. A dynamic balancing analysis of the station using geographical representation offer good insight on the movements of the bikes associated with a cluster. Then, a complex network approach is also used to extract more topological information about the bike-sharing network made from the stations and the trips. All these transdisciplinary approaches used together produce new operational knowledge that can be useful for the operators and the logistics to overcome the redistribution problem as well as improving the quality of the service.

Concentrating photovoltaic-thermal (CPVT) systems, which can be integrated on buildings façades and use low-accuracy trackers and standard cells, have the potential to produce cost-effective electricity and heat. In this paper, a refractive cylindrical CPVT module with cells directly immersed in deionized water (DIW) or isopropyl alcohol (IPA) is designed, fabricated and experimentally tested. The interfaces between the cylinder and the fluids cavity have been optimized to maximize optical efficiency and irradiance uniformity, obtaining better results for a geometric concentration of 10x and IPA. The system achieves an optical efficiency of 81%, an acceptance angle of 1.07° and a non-uniformity coefficient of 0.13.

We present a detailed examination of a multiple InxGa1−xN quantum well (QW) structure for optoelectronic applications.

Solar energy can play a leading role in reducing the current reliance on fossil fuels and in increasingrenewable energy integration in the built environment, and its affordable deployment is widely recog-nised as an important global engineering grand challenge. Of particular interest are solar energy systemsbased on hybrid photovoltaic-thermal (PV-T) collectors, which can reach overall efficiencies of 70% orhigher, with electrical efficiencies up to 15–20% and thermal efficiencies in excess of 50%, dependingon the conditions. In most applications, the electrical output of a hybrid PV-T system is the priority, hencethe contacting fluid is used to cool the PV cells and to maximise their electrical performance, whichimposes a limit on the fluid’s downstream use. When optimising the overall output of PV-T systemsfor combined heating and/or cooling provision, this solution can cover more than 60% of the heatingand about 50% of the cooling demands of households in the urban environment. To achieve this, PV-Tsystems can be coupled to heat pumps, or absorption refrigeration systems as viable alternatives tovapour-compression systems. This work considers the techno-economic challenges of such systems,when aiming at a low cost per kW h of combined energy generation (co- or tri-generation) in the housingsector. First, the technical viability and affordability of the proposed systems are studied in ten Europeanlocations, with local weather profiles, using annually and monthly averaged solar-irradiance and energy-demand data relating to homes with a total floor area of 100 m2(4–5 persons) and a rooftop area of50 m2. Based on annual simulations, Seville, Rome, Madrid and Bucharest emerge as the most promisinglocations from those examined, and the most efficient system configuration involves coupling PV-T pan-els to water-to-water heat pumps that use the PV-T thermal output to maximise the system’s COP. Hourlyresolved transient models are then defined in TRNSYS, including thermal energy storage, in order to pro-vide detailed estimates of system performance, since it is found that the temporal resolution (e.g. hourly,daily, yearly) of the simulations strongly affects their predicted performance. The TRNSYS results indicatethat PV-T systems have the potential to cover 60% of the combined (space and hot water) heating andalmost 100% of the cooling demands of homes (annually integrated) at all four aforementioned locations.Finally, when accounting for all useful energy outputs from the PV-T systems, the overall levelised cost ofenergy of these systems is found to be in the range of 0.06–0.12€/kW h, which is 30–40% lower than thatof equivalent PV-only systems Peer Reviewed

Home-based teleworking, associated with sedentary behavior, may impair self-reported adult health status. Current exercise recommendations, based on universal recipes, may be insufficient or even misleading to promote healthy teleworking. From the Network Physiology of Exercise perspective, health is redefined as an adaptive emergent state, product of dynamic interactions among multiple levels (from genetic to social) that cannot be reduced to a few dimensions. Under such a perspective, fitness development is focused on enhancing the individual functional diversity potential, which is better achieved through varied and personalized exercise proposals. This paper discusses some myths related to ideal or unique recommendations, like the ideal exercise or posture, and the contribution of recent computer technologies and applications for prescribing exercise and assessing fitness. Highlighting the need for creating personalized working environments and strengthening the active contribution of users in the process, new recommendations related to teleworking posture, home exercise counselling, exercise monitoring and to the roles of healthcare and exercise professionals are proposed. Instead of exercise prescribers, professionals act as co-designers that help users to learn, co-adapt and adequately contextualize exercise in order to promote their somatic awareness, job satisfaction, productivity, work–life balance, wellbeing and health.