Energy use in residential buildings: Impact of building automation control systems on energy performance and flexibility

This work shows the results of a research activity aimed at characterizing the energy habits of Italian residential users. In detail, by the energy simulation of a buildings sample, the opportunity to implement a demand/response program (DR) has been investigated. Italian residential utilities are poorly electrified and flexible loads are low. The presence of an automation system is an essential requirement for participating in a DR program and, in addition, it can allow important reductions in energy consumption. In this work the characteristics of three control systems have been defined, based on the services incidence on energy consumptions along with a sensitivity analysis on some energy drivers. Using the procedure established by the European Standard EN 15232, the achievable energy and economic savings have been evaluated. Finally, a financial analysis of the investments has been carried out, considering also the incentives provided by the Italian regulations. The payback time is generally not very long: depending on the control system features it varies from 7 to 10 years; moreover, the automation system installation within dwellings is a relatively simple activity, which is characterized by a limited execution times and by an initial expenditure ranging in 1000 € to 4000 €, related to the three sample systems

How climate change affects the building energy consumptions due to cooling, heating, and electricity demands of italian residential sector

Climate change affects the buildings’ performance, significantly influencing energy consumption, as well as the indoor thermal comfort. As a consequence, the growing outdoor environmental temperatures entail a slight reduction in heating consumption and an increase in cooling consumption, with different overall effects depending on the latitudes. This document focuses attention on the Italian residential sector, considering the current and reduced meteorological data, in anticipation of future climate scenarios. According to a sample of 419 buildings, referring to the climatic conditions of Milan, Florence, Rome, and Naples, the heating and cooling needs are calculated by a simplified dynamic model, in current and future conditions. The effects of the simplest climate adaptation measure, represented by the introduction of new air conditioners, have been also evaluated. The simulations results show an important reduction in complex energy consumption (Milan −6%, Florence −22%, Rome −25%, Naples −30%), due to the greater incidence of heating demand in the Italian context. However, the increase in air conditioning electrical consumption over the hot season (Milan +11%, Florence +20%, Rome +19%, Naples +16%) can play a critical role for the electrical system; for that reason, the introduction of photovoltaic arrays as a compensatory measure have been analysed

Spectral broadening in self-assembled GaAs quantum dots with narrow size distribution

The control over the spectral broadening of an ensemble of emitters, mainly attributable to the size and shape dispersion and the homogenous broadening mechanisms, is crucial to several applications of quantum dots. We present a convenient self-assembly approach to deliver strain-free GaAs quantum dots with size distribution below 15%, due to the control of the growth parameters during the preliminary formation of the Ga droplets. This results in an ensemble photoluminescence linewidth of 19 meV at 14 K. The narrow emission band and the absence of a wetting layer promoting dot-dot coupling allow us to deconvolve the contribution of phonon broadening in the ensemble photoluminescence and study it in a wide temperature range.Comment: 9 pages, 4 figure

Cogenerazione integrata in un sistema ibrido con motore ad idrometano per un impianto natatorio

L’oggetto del presente studio è un impianto di cogenerazione alimentato ad idrometano asservito alla gestione termica di una piscina costruita all’interno del centro sportivo universitario di Tor di Quinto. Il laboratorio di sperimentazione connesso alla realizzazione di tale impianto ha come obiettivi la promozione di sistemi innovativi per la gestione energetica ed economica dell’Ateneo e la sostenibilità ambientale all’interno di una grande città come Roma. Di fatto, tale laboratorio si configura come uno dei nuovi centri di autoproduzione facente capo alla smart grid della Sapienza costituendo il primo sistema ibrido realizzato in Italia che impiega, in modo sinergico e razionale, le tecnologie della cogenerazione, del fotovoltaico e della produzione di idrogeno a bassa pressione ( 15 bar ) mediante processo elettrolitico. A partire dai risultati ottenuti da uno studio di fattibilità sulla piscina si è determinata la taglia di 60 kW elettrici per il cogeneratore. Per l’ alimentazione del motore a combustione interna è stata prevista la possibilità di operare con gas metano al 100 %, oppure con una miscela arricchita di idrogeno di composizione modulabile ( nel range 0 - 10 % in volume ) mediante interposizione di un buffer di disaccoppiamento (capacità: 60 litri) ed apposita apparecchiatura miscelatrice. L’idrogeno viene prodotto da un elettrolizzatore alcalino (potenzialità: 1.1 Nm3/h ) che assorbe una potenza elettrica di 5.5 kW in parte dalla rete e in parte da un impianto fotovoltaico (6 kW) grid - connected totalmente integrato in facciata di una palazzina adiacente. Con il completamento dell’installazione del sistema di analisi fumi in continuo sarà possibile effettuare i test sul motore e valutare le prestazioni energetiche ed ambientali dell’intero sistema ibrid

Prognostic Value of Plasma and Urine Glycosaminoglycan Scores in Clear Cell Renal Cell Carcinoma

The prognosis of metastatic clear cell renal cell carcinoma (ccRCC) vastly improved since the introduction of antiangiogenic targeted therapy. However, it is still unclear which biological processes underlie ccRCC aggressiveness and affect prognosis. Here, we checked whether a recently discovered systems biomarker based on plasmatic or urinary measurements of glycosaminoglycans aggregated into diagnostic scores correlated with ccRCC prognosis.Thirty-one patients with a diagnosis of ccRCC (23 metastatic) were prospectively enrolled and their urine and plasma biomarker scores were correlated to progression-free survival (PFS) and overall survival (OS) as either a dichotomous (Low vs. High) or a continuous variable in a multivariate survival analysis.The survival difference between High vs. Low-scored patients was significant in the case of urine scores (2-year PFS rate = 53.3% vs. 100%, p = 310-4 and 2-year OS rate = 73.3% vs. 100%, p = 0.0078) and in the case of OS for plasma scores (2-year PFS rate = 60% vs. 84%, p = 0.0591 and 2-year OS rate = 66.7% vs. 90%, p = 0.0206). In multivariate analysis, the urine biomarker score was an independent predictor of PFS (HR: 4.62, 95% CI: 1.66 to 12.83, p = 0.003) and OS (HR: 10.13, 95% CI: 1.80 to 57.04, p = 0.009).This is the first report on an association between plasma or urine GAG scores and the prognosis of ccRCC patients. Prospective trials validating the prognostic and predictive role of this novel systems biomarker are warranted

High-yield fabrication of entangled photon emitters for hybrid quantum networking using high-temperature droplet epitaxy

Several semiconductor quantum dot techniques have been investigated for the generation of entangled photon pairs. Among the other techniques, droplet epitaxy enables the control of the shape, size, density, and emission wavelength of the quantum emitters. However, the fraction of the entanglement-ready quantum dots that can be fabricated with this method is still limited to around 5%, and matching the energy of the entangled photons to atomic transitions (a promising route towards quantum networking) remains an outstanding challenge. Here, we overcome these obstacles by introducing a modified approach to droplet epitaxy on a high symmetry (111)A substrate, where the fundamental crystallization step is performed at a significantly higher temperature as compared to previous reports. Our method drastically improves the yield of entanglement-ready photon sources near the emission wavelength of interest, which can be as high as 95% due to the low values of fine structure splitting and radiative lifetime, together with the reduced exciton dephasing offered by the choice of GaAs/AlGaAs materials. The quantum dots are designed to emit in the operating spectral region of Rb-based slow-light media, providing a viable technology for quantum repeater stations.Comment: 14 pages, 3 figure

A Novel Block-based Watermarking Scheme Using the SVD Transform

In this paper, a block-based watermarking scheme based on the Singular Value Decomposition (SVD) is proposed. Our watermark, a pseudo-random Gaussian sequence, is embedded by modifying the angles formed by the right singular vectors of each block of the original image. The orthogonality property of the right singular vector matrix is preserved during the embedding process. Several experiments have been carried out to test the performance of the proposed scheme against different attack scenarios. We conclude that the proposed scheme is resistant against common signal processing operations and attacks, while it preserves the quality of the original image

How the italian residential sector could contribute to load flexibility in demand response activities: a methodology for residential clustering and developing a flexibility strategy

This work aims at exploring the potential contribution of the Italian residential sector in implementing load flexibility for Demand Response activities. In detail, by combining experimental and statistical approaches, a method to estimate the load profile of a dwelling cluster of 751 units has been presented. To do so, 14 dwelling archetypes have been defined and the algorithm to categorise the sample units has been built. Then, once the potential flexible loads for each archetype have been evaluated, a control strategy for applying load time shifting has been implemented. That strategy accounts for both the power demand profile and the hourly electricity price. Specifically, it has been assumed that end users access a pricing mechanism following the hourly trend of electricity economic value, which is traded day by day in the Italian spot market, instead of the current Time of Use (TOU) system. In such a way, it is possible to flatten the dwellings cluster profile, limiting undesired and unexpected results on the balancing market. In the end, monthly and yearly flexibility indexes have been defined along with the strategy effectiveness parameter. From calculations, it emerges that a dwelling cluster for the Italian residential sector is characterised by a flexibility index of 10.3% and by a strategy effectiveness equal to 34%. It is noteworthy that the highest values for flexibility purpose have been registered over the heating season (winter) for the weekends

An international survey exploring the management of pilonidal disease

AIM: Pilonidal disease (PD) is a common debilitating condition frequently seen in surgical practice. Several available treatments carry different benefit/risk balances. The aim of this study was to snapshot the current management of PD across European countries.METHOD: Members affiliated to the European Society of Coloproctology were invited to join the survey. An invitation was extended to others via social media. The predictive power of respondents' and hospitals' demographics on the change of therapeutic approach was explored.RESULTS: Respondents (n = 452) were mostly men (77%), aged 26-60 years, practising in both academic and public hospitals and with fair distribution between colorectal (51%) and general (48%) surgeons. A total of 331 (73%) respondents recommended surgery at first presentation of the disease. Up to 80% of them recommended antibiotic therapy and 95% did not use any classification of PD. A primary closure technique was the preferred procedure (29%), followed by open technique (22%), flap creation (7%), sinusectomy (7%) and marsupialization (7%). Approximately 27% of subjects would choose the same surgical technique even after a failure. Almost half (46%) perform surgery as office based. A conservative approach was negatively associated with acutely presenting PD (p &lt; 0.001). Respondents who were not considering tailored surgery based on patient presentation tended to change their approach in the case of a failed procedure.CONCLUSION: With the caveat of a heterogeneous number of respondents across countries, the results of our snapshot survey may inform the development of future guidelines.</p

An international survey exploring the management of pilonidal disease

AIM: Pilonidal disease (PD) is a common debilitating condition frequently seen in surgical practice. Several available treatments carry different benefit/risk balances. The aim of this study was to snapshot the current management of PD across European countries.METHOD: Members affiliated to the European Society of Coloproctology were invited to join the survey. An invitation was extended to others via social media. The predictive power of respondents' and hospitals' demographics on the change of therapeutic approach was explored.RESULTS: Respondents (n = 452) were mostly men (77%), aged 26-60 years, practising in both academic and public hospitals and with fair distribution between colorectal (51%) and general (48%) surgeons. A total of 331 (73%) respondents recommended surgery at first presentation of the disease. Up to 80% of them recommended antibiotic therapy and 95% did not use any classification of PD. A primary closure technique was the preferred procedure (29%), followed by open technique (22%), flap creation (7%), sinusectomy (7%) and marsupialization (7%). Approximately 27% of subjects would choose the same surgical technique even after a failure. Almost half (46%) perform surgery as office based. A conservative approach was negatively associated with acutely presenting PD (p &lt; 0.001). Respondents who were not considering tailored surgery based on patient presentation tended to change their approach in the case of a failed procedure.CONCLUSION: With the caveat of a heterogeneous number of respondents across countries, the results of our snapshot survey may inform the development of future guidelines.</p