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Innovation Districts are rising as the banners of the new urban, economic, and social paradigm and as a solution to the renaissance of inner cities since they expedite the creation and commercialization of new ideas which leverage the city goals and its technologic and economic attributes. The configuration of accurate indicators to measure the degree of achievement of the innovation district goals is one of the main requirements to ensure district proper development. Even when the study of innovation districts is a topic that is increasingly under study, little is still known about the insight, and it is still needed tools that favor their evolution and development. The aim of this paper is two-fold: on the one hand, it seeks to collect and analyze the indicators that have been used in literature to measure the degree of maturity over the course of the 20-year existence of the 22@Barcelona, an area of innovation that transformed an old industrial district into a knowledge-based one. On the other hand, guided by the four dimensions of the Knowledge Base Urban Development theory and the main actors that make up Triple Helix approach, the paper designs a framework of indicators in the four spheres that shape the regeneration of the district, that is, urban, economic, social and governance. As we shall see, a total of 47 indicators are proposed, indicating for each of them: the environment in which it is applied, the main purpose to which it responds, and the main actor with the greatest power of action over it.

In this work, an indirect method for the detection of voltage unbalance in electrical engines using an optical fiber sensor is presented. The in-line fiber etalon structure has been designed and used to detect 0-5% voltage unbalances in the frequency range up to 500 Hz. The interferometric sensing mechanism of the sensor allows a high sensitivity with the additional advantages of EMI immunity and high dielectric isolation. In order to prove this claim, a 1.5 kW squirrel cage induction motor is unbalanced and its vibration analyzed. It is shown that a precise unbalance factor can be detected without accessing to the electric part of the machine and an accurate monitoring can be obtained using the analysis proposed. This scheme can be applied to reduce the oscillating electromagnetic torque, power losses and temperature rise due to unbalance, and leading to a higher efficiency and the extension of the life of the machine

The magnetic properties of LiM0.5Mn1.5O4 (M=Ni and Cu) spinels, materials of interest as electrodes for Li-ion batteries, have been studied and interpreted with the help of the first-principles calculation method. The magnetic susceptibility of the Ni compound, that behaves virtually as stoichiometric normal spinel, is consistent with the well-established magnetic model of the spinel structure that leads to ferrimagnetism. However, the Cu spinel was oxygen deficient and showed significant divergences from this model. The ferromagnetic component of this spinel was dependent on the calcining temperature and was smaller to that predicted by the magnetic model. The special crystal structure of the spinel, namely, oxygen deficiency and increased occupancy of the tetrahedral sites by Cu ions, satisfactorily explains the more complex magnetic behavior observed, further supported by the results of the first-principles electronic structure computations.

The catalytic pyrolysis of low-density polyethylene (LDPE) and high-density polyethylene (HDPE) over the HZSM5 catalyst in a batch reactor has been studied, and an analysis of the evolution of the products generated with temperature is presented. As expected, the catalyst favored the formation of gaseous compounds. The composition of the products obtained depended upon the polyethylene structure, especially at the beginning of the degradation process. Initially during the catalytic cracking of LDPE, olefins were the major compounds obtained in both the gaseous and condensed phases. As the temperature was increased, the composition of the gases remained constant, whereas in the condensed fraction, the olefins yield decreased, resulting in aromatics being the compounds predominantly generated. With HDPE, a greater quantity of paraffins and aromatics formed at the beginning of the decomposition process in the gaseous and condensed products, respectively, as compared to LDPE. As the temperature was increased,...

It is important for a modern consumer of thermal energy to know and be able to reduce the consumption of thermal energy, for which purpose an energy audit should be conducted. Today, three types of energy audit of residential buildings are used in Ukraine. The first one is development of the energy performance certificate of the building. The obtained energy performance certificate will give an idea of the level of thermal losses of the building and identify the main areas where measures to reduce the consumption of energy resources should be taken. The second method involves carrying out experimental studies to determine the class of air permeability of enclosing structures, which also makes it possible to assess the level of heat losses of the building and the condition of the ventilation system of the building. The third type of energy audit involves carrying out thermal imaging of the building envelope for the subsequent analysis of infrared images. A methodological approach has been developed for processing multiple infrared images. An energy inspection of a residential house has been conducted on the basis of which an energy performance certificate was compiled. The premises of the residential building have been tested for air permeability. Considering the main types of energy audit, its advantages and disadvantages have been determined both for the consumer and for the employees who conduct the audit.  

Abstract In this research, a series of combustion experiments of Indonesian oil sands using a thermal analyzer were conducted at three heating rates (10, 20, and 50 °C min − 1 ) over the temperature range of 20–900 °C under atmospheric pressure. The obtained DTG curves revealed that combustion reactions occurred at three different stages in all the samples. The DTG peak, which is a measure of the relative reactivity, shifted to higher temperature with increasing heating rate. The ignition temperature was determined by using the TG-DTG extrapolation method, and the other principal combustion features, such as maximum weight loss rate, combustion release index and average quality reactivity, were all obtained. Simultaneously, an activation energy distribution method was employed to determine the combustion kinetics and then the relationship between the energy distribution E and the applicable volatile content/the total volatiles ratio V / V * was obtained by plotting the V / V * value against the corresponding E values. Furthermore, the ln k 0 vs. V / V * relationship was calculated. At the last, the ash composition of oil sands was determined by adopting the chemical analysis method.

Abstract Given climate change predictions of a warmer world, there is growing concern that insulation-led improvements in building fabric aimed at reducing carbon emissions will exacerbate overheating. If true, this would seriously affect building regulations all over the world which have moved towards increased insulation regimes. Despite extensive research, the literature has failed to resolve the controversy of insulation performance, primarily due to varied scope and limited comparability of results. We approach this problem through carefully constructed pairwise comparisons designed to isolate the effect of insulation on overheating. We encompass the complete range of relevant variables: latitude, climate, insulation, thermal mass, glazing ratio, shading, occupancy, infiltration, ventilation, orientation, and thermal comfort models — creating 576,000 building variants. Data mining techniques are implemented in a novel framework to analyse this large dataset. To provide confidence, the modelling was validated against data collected from well-insulated dwellings. Our results demonstrate that all parameters have a significant impact on overheating risk. Although insulation is seen to both decrease and increase overheating, depending on the influence of other parameters, parameter ranking shows that insulation only accounts for up to 5% of overall overheating response. Indeed, in cases that are not already overheating through poor design, there is a strong overall tendency for increased insulation to reduce overheating. These results suggest that, in cases with acceptable overheating levels (below 3.7%), the use of improved insulation levels as part of a national climate change mitigation policy is not only sensible, but also helps deliver better indoor thermal environments.