Archivio istituzionale della ricerca - Alma Mater Studiorum Università di Bologna
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Domestic Hot Water Production in Residential Buildings: Energetic Analysis of Different Systems Through Dynamic Simulations
No full textThe energy used for Domestic Hot Water (DHW) production currently accounts for approximately 15–40% of the total energy needed in residential buildings. The present study deals with the energetic optimization of the Domestic Hot Water (DHW) system in a residential building of 10 apartments in Bologna, Italy. Two different systems are analyzed: the first has one centralized tank storage and a circulation loop, and the second has specific decentralized tanks (one for each apartment) with an internal heat exchanger. In both systems, the water is heated by an Electrical Heat Pump (EHP) coupled to a central storage tank. The energy performance analysis of the two DHW models is evaluated by dynamic simulations under different scenarios (for case two) of charging the decentralized storage tanks by circulating pump units. The results allow an evaluation of the DHW consumption profile, temperature variation in both the system’s central storage and (for case two) decentralized tanks and the annual electrical/thermal energy analysis
ESG score and volatility in the European stock market
No full textWe aim to investigate the relationship between ESG score and assets characteristics, focusing on volatility.We classify stocks based on both high/lowESG scores and high/low ESG momentum and we evaluate ESG effects by measuring the distance between the two group distributions. The analysis of stocks in the STOXX600 Index from 2017 to 2022 suggests that companies with higher ESG outperform companies with lower ESG, which are consistently characterized by higher volatility. Our findings also highlight and compare the effects related to the COVID pandemic and the war in Ukraine
Spatial Multicriteria Decision Aiding for Regional Energy Planning and Assessment. The Case Study of Gotland, Sweden
No full textThe transition to renewable energy requires regional planning approaches that integrate spatial, environmental, and social dimensions. This study develops a Multi-Criteria Spatial Decision-Support System (MC-SDSS) to support regional energy planning by combining geospatial data analysis, future scenario development, and multi-criteria evaluation techniques. The methodology is structured into four phases - contextual analysis, energy potential mapping and future scenarios, integrated evaluation and decision support, and implementation and monitoring. The approach is applied to Gotland, Sweden, a region with ambitious decarbonization goals and unique geographic characteristics. Renewable energy potential is assessed through thematic mapping using Geographic Information Systems (GIS) tools, focusing on wind, solar, and biomass resources. In the evaluation phase, a Spatial Multi-Criteria Analysis (SMCA) is conducted to assess and compare the scenarios. Five main criteria are identified Society and Culture, Technology and Infrastructure, Economy, Land-use, Environment each associated with specific measurable spatial indicators. Criteria weights are derived using the Simple Multi-Attribute Rating Technique Exploiting Ranks (SMARTER) method with the purpose of weighting the indicators maps and then aggregating them into suitability maps for Renewable Energy Sources (RES) power plants installation. By embedding the decision-support system within a spatial planning perspective, this study promotes a transparent, replicable, and stakeholder-sensitive approach to regional energy planning. The proposed framework supports the identification of hybrid scenarios and fosters alignment between energy objectives, territorial characteristics, and community needs—contributing to more resilient and place-based energy transitions
Study on the accuracy of Multi-GNSS PPP for different observing sessions time spans using PRIDE PPP-AR open-source software package
Full text linkThe Precise Point Positioning (PPP) approach to GNSS observables is widely used for processing data from permanent stations, providing highly precise coordinates. However, the performance of PPP for observation sessions shorter than 24 h has not yet been thoroughly investigated in the case of multi-constellation acquisitions. In recent years, the PRIDE PPP-AR software package has been made freely available. Since it includes a graphical user interface (GUI) version that runs under Windows, it can also be easily used by technical surveyors aiming to process data acquired from a single GNSS receiver. This is particularly valuable for surveys conducted in areas lacking dense geodetic infrastructures or reliable augmentation services. In this paper, based on a wide and consistent dataset, the coordinate precision obtained from observation sessions ranging from 30 min to 24 h processed with PRIDE PPP-AR is analyzed. In addition to multi-constellation GNSS data (GPS + Galileo + GLONASS + BeiDou), independent GPS-only and Galileo-only processing was also evaluated. Furthermore, the reliability of the formal errors provided by the software was examined, as these represent the only available information for assessing coordinate quality in surveys that lack geometric redundancy. While several online PPP services already exist, PRIDE PPP-AR overcomes common limitations related to the number of processed files and the choice of GNSS constellations. The results show that two-hour observation sessions can reliably achieve horizontal coordinate accuracy within 2 cm and vertical accuracy within 5 cm, whereas 30-minute sessions are suitable for applications requiring 5–10 cm accuracy
Impact of treated wastewater agricultural reuse on orchards and irrigation systems
No full textTreated wastewater is increasingly used for crop irrigation and fertigation as it provides essential minerals for plant nutrition. However, it also poses challenges such as high salinity, phytotoxic compounds, and biofilm formation, which can affect plant health, reduce yield, and lower irrigation efficiency. This study aimed to evaluate the impact of secondary treated wastewater (SW) on soil chemical properties, plant physiological and nutritional performances, and irrigation system efficiency. Over two irrigation seasons (i.e., 2021 and 2022), potted peach trees were irrigated with SW, with or without additional fertilization, and compared to fresh water with fertilizer. With this purpose, a smart fertigation system was employed to balance nutrient inputs based on continuous water quality monitoring. SW alone partially met plant nutrient demands, though additional fertilization was needed for optimal growth. It slightly increased soil electrical conductivity (of about 0.7 dS m−1) and trace element levels, particularly late in the season, but had no adverse effects on plant water status or heavy metal accumulation in leaves. SW integrated with mineral fertigation, apart from slightly anticipating fruit ripening of about one week, generally showed similar fruit quality traits to fresh water-irrigated tree, not causing increase in heavy metals and trace element concentrations. However, the use of SW reduced dripper irrigation efficiency of about 10.5%, especially when combined with fertilization
Digital trade, data protection and the EU adequacy club
Full text linkBetween 2000 and 2020, the EU granted 14 so-called adequacy decisions, permitting EU citizens’ personal data to flow freely between the EU and the respective trading partners, including among the countries accorded adequacy. Most adequacy decisions are unilateral, complementing the more commonly observed and analyzed mutual recognition arrangements for technical regulations. Using structural gravity to assess the relationship between EU adequacy decisions and digital trade, and applying different approaches to define digital trade, we find that adequacy increases bilateral digital trade between the EU and the adequate countries by 7 to 9 percent compared to non-digital trade. We also provide evidence of a “club effect,” with digital trade increasing between countries that have been granted adequacy, but only to the extent that the US is part of the club. Using synthetic control methods, we show that the magnitude of the club effect varies across countries
Premature rupture of the membranes in twin pregnancies: Maternal and fetal outcomes
Full text linkAim: To analyse outcomes of twin pregnancies complicated by membranes rupture between 24 and 37 weeks of gestation. Methods: Retrospective matched cohort study on twin pregnancies with premature membranes rupture, through review of clinical records at the Policlinico S. Orsola di Bologna, a tertiary hospital, between 2010 and 2020. Results: 171 twin pregnancies were admitted, over 10 years, with a diagnosis of premature rupture of membranes PPROM (fluid pooling on speculum and/or Insulin Growth Factor Binding Protein1 positive on vaginal secretions and oligohydramnios at ultrasound). The maternal and fetal outcomes of these pregnancies were compared to those of uneventful 178 twin pregnancies. There was no difference on risk factors. The mean gestational age at PROM was 33.9 weeks. PPROM newborns showed a lower birth weight (2072 ± 515 g vs. 2384 ± 454, p < 0.001), a higher rate of admission to neonatal intensive care unit (45.6% vs 22.2%, p < 0.001), and a higher rate of adverse outcomes, even if it did not achieve statistical significance (crude OR: 3.05, 95% CI: 2.04-4.56; adjusted OR: 1.45, 95% CI: 0.87-2.41). No cases of sepsis were found. Conclusion: In our cohort of twin pregnancies no significative risk factors for premature rupture of membranes were found. Although PROM is known to increase infectious morbidity, not all patients will develop these complications. PROM in twin pregnancies does not appear to be an independent risk factor for adverse maternal or neonatal outcomes when the effect of prematurity is accounted fo. Strategies to prolong pregnancy, when feasible, may mitigate adverse neonatal outcomes associated with PPROM in twin pregnancies
Amine- and hydroxyl-functionalized copolymers as lubricant additives on Si-doped DLC: A comparative experimental and computational study of their tribological performance
No full textDiamond-like carbon (DLC) coatings combined with functionalized copolymers are promising environmentally friendly lubrication systems and alternatives to metal containing additives. This study examines silicon-doped DLC (Si-DLC) lubricated with block copolymers bearing amine (DMAEMA) or hydroxyl (HEMA) groups. Friction and wear tests over 20–80 °C and under different loads show that both copolymers provide lower friction relative to nonfunctionalized PLMA, but only DMAEMA sustains low friction and low wear under 100 N boundary lubrication. To clarify the mechanism, a distribution-based ab initio adsorption analysis was carried out on an amorphous Si-DLC model using a screening procedure across multiple surface sites and molecular orientations. The adsorption energy distributions show that DMAEMA frequently forms stable N–Si bonds (often ≤ − 2.0 eV) and dual N–Si + O–Si bonds (about − 2.4 eV), whereas HEMA centers near − 1.5 eV for OH–Si bonds, with weaker dual OH–Si + O–Si bonding (about − 2.0 eV). This separation of adsorption energy distributions accounts for the divergence in high load behavior. Together, experiments and modeling underline the role of functional group chemistry in determining tribological performances on Si-DLC, and adsorption energy distributions, and guide additive selection for Si DLC in electric and hybrid drivetrains
Abstractive Summarization through the Prism of Decoding Strategies
No full textIn natural language generation, abstractive summarization (AS) is advancing rapidly due to transformer-based language models (LMs). Although decoding strategies significantly influence generated summaries, their significance is often overlooked. Given the abundance of token selection heuristics and associated hyperparameters, the community needs guidance to make well-informed decisions based on the specific task and target metrics. To address this gap, we conduct a comparative assessment of the effectiveness and efficiency of decoding-time techniques for short, long, and multi-document AS. We explore over 3,500 combinations involving three widely used million-scale autoregressive encoder-decoder LMs, two billion-scale decoder-only LMs, six datasets, and nine decoding settings. Our findings highlight that optimized decoding choices can lead to substantial performance improvements. Alongside human evaluation, we quantitatively measure effects using ten automatic metrics, covering dimensions such as semantic similarity, factuality, compression, redundancy, and carbon footprint. To set the stage for differentiable selection and optimization of decoding options, we introduce PRISM, a first-of-its-kind dataset that pairs AS gold input-output examples with our LM predictions across a diverse range of decoding options
Early postharvest application of LED lighting enhances strawberry quality during storage
No full textStrawberry (Fragaria × ananassa Duch.) perishability challenges postharvest quality retention. Traditional postharvest methods have limitations, and early harvesting to extend shelf-life often compromises sensory attributes. This study investigated whether 24 h or 48 h treatments performed at the beginning of postharvest with Red, Blue, Far-Red, or UV-A light-emitting diode (LED) light could improve 'Elsanta' strawberry quality during subsequent 7-day storage at suboptimal temperature (5 °C). Fruit quality attributes, including firmness, weight loss, soluble solids content (SSC), titratable acidity (TA), anthocyanins, and volatile organic compounds (VOCs), were assessed. While LED treatments did not significantly affect firmness, they generally increased weight loss compared to dark controls (particularly after 48 h Blue/Red/Far-Red exposures). Light effects on SSC were complex and duration-dependent. Notably, all LED treatments significantly enhanced total anthocyanin content (especially after 48 h exposure), although instrumental color measurements remained unchanged. Compared to dark controls Blue and Red light (especially after 48 h) significantly increased the concentration of key aroma-related VOCs, for the most esters. In conclusion a brief, early postharvest LED exposure, particularly using Blue and Red light, can trigger lasting beneficial effects, enhancing nutritionally relevant anthocyanins and aroma-defining VOCs during storage at 5 °C. This suggests an 'early signal' mechanism and offers a potentially practical strategy to improve strawberry quality, mitigating negative impacts of commercial early harvesting practices and potentially benefiting other non-climacteric fruits