Modelling Ordinal Responses with Uncertainty: a Hierarchical Marginal Model with Latent Uncertainty components

In responding to rating questions, an individual may give answers either according to his/her knowledge/awareness or to his/her level of indecision/uncertainty, typically driven by a response style. As ignoring this dual behaviour may lead to misleading results, we define a multivariate model for ordinal rating responses, by introducing, for every item, a binary latent variable that discriminates aware from uncertain responses. Some independence assumptions among latent and observable variables characterize the uncertain behaviour and make the model easier to interpret. Uncertain responses are modelled by specifying probability distributions that can depict different response styles characterizing the uncertain raters. A marginal parametrization allows a simple and direct interpretation of the parameters in terms of association among aware responses and their dependence on explanatory factors. The effectiveness of the proposed model is attested through an application to real data and supported by a Monte Carlo study

A language-familiarity effect for speaker discrimination without comprehension

The influence of language familiarity upon speaker identification is well established, to such an extent that it has been argued that “Human voice recognition depends on language ability” [Perrachione TK, Del Tufo SN, Gabrieli JDE (2011) Science 333(6042):595]. However, 7-mo-old infants discriminate speakers of their mother tongue better than they do foreign speakers [Johnson EK, Westrek E, Nazzi T, Cutler A (2011) Dev Sci 14(5):1002–1011] despite their limited speech comprehension abilities, suggesting that speaker discrimination may rely on familiarity with the sound structure of one’s native language rather than the ability to comprehend speech. To test this hypothesis, we asked Chinese and English adult participants to rate speaker dissimilarity in pairs of sentences in English or Mandarin that were first time-reversed to render them unintelligible. Even in these conditions a language-familiarity effect was observed: Both Chinese and English listeners rated pairs of native-language speakers as more dissimilar than foreign-language speakers, despite their inability to understand the material. Our data indicate that the language familiarity effect is not based on comprehension but rather on familiarity with the phonology of one’s native language. This effect may stem from a mechanism analogous to the “other-race” effect in face recognition

Study of gas-steam combined cycle power plants integrated with MCFC for carbon dioxide capture

Abstract In the field of fossil-fuel based technologies, natural gas combined cycle (NGCC) power plants are currently the best option for electricity generation, having an efficiency close to 60%. However, they produce significant CO2 emissions, amounting to around 0.4 tonne/MWh for new installations. Among the carbon capture and sequestration (CCS) technologies, the process based on chemical absorption is a well-established technology, but markedly reduces the NGCC performances. On the other side, the integration of molten carbonate fuel cells (MCFCs) is recognized as an attractive option to overcome the main drawbacks of traditional CCS technologies. If the cathode side is fed by NGCC exhaust gases, the MCFC operates as a CO2 concentrator, beside providing an additional generating capacity. In this paper the integration of MCFC into a two pressure levels combined cycle is investigated through an energy analysis. To improve the efficiency of MCFC and its integration within the NGCC, plant configurations based on two different gas recirculation options are analyzed. The first is a traditional recirculation of exhaust gases at the compressor inlet; the second, mainly involving the MCFC stack, is based on recirculating a fraction of anode exhaust gases at the cathode inlet. Effects of MCFC operating conditions on energy and environmental performances of the integrated system are evaluated

Energy, Economic and Environmental Assessments for Gas-turbine Integration into an Existing Coal-fired Power Plant

Abstract The concept of repowering existing power plants has been recently revalued, in the light of the increasing energy needs, combined with the cost and the difficulty in developing new generating capacity. Among technologies for existing steam power plants, feedwater repowering is considered one of the less-intrusive and cost-effective option to expand capacity, improve efficiency and reduce the pollutants emissions. This paper aims to evaluate the effects of feedwater repowering operating conditions on energy, environmental and economic system performances. Considering a 600 MW coal fired power plant as a study case, two feedwater repowering configurations are investigated. In the first case, a simple throttling of high pressure regenerative steam extractions is operated; in the second configuration, the feedwater upstream the boiler inlet is partially preheated using the waste heat of an additional gas turbine. In both cases, a characteristic plane is introduced for comparing energy, economic and environmental performances of feedwater repowering options, at different condenser overloads and fossil boiler modes of operation

How to pursue the Whole Life Carbon vision: a method to assess buildings’ Embodied Carbon.

Il volume raccoglie gli atti della 2a ed. del convegno "BEYOND ALL LIMITS. International Conference on Sustainability in Architecture, Planning, and Design", tenutosi nei giorni 11 e 12 maggio 2022, presso il Complesso del Belvedere di San Leucio, sede di OFFICINA VANVITELLI. Il convegno è stato promosso e organizzato dal Dipartimento di Architettura e Disegno Industriale dell'Università degli Studi della Campania "Luigi Vanvitelli", in partnership con la Faculty of Architecture della Çankaya University di Ankara e la Faculty of Engineering della University of Strathclyde di Glasgow. L'obiettivo principale di questo convegno scientifico e multidisciplinare, che ha interessato i campi dell'architettura, della pianificazione e del design, è stato quello di affrontare il tema della sostenibilità all’interno dell'attuale dibattito internazionale scaturito dal New European Bauhaus (NEB). The design and construction of CO2-neutral buildings by 2050 will be possible through many actions and strategies, including new metrics and indicators that would contribute to the accounting process for greenhouse gas emissions over the building’s life cycle. Among the range of helpful indicators is Embodied Carbon (EC). Standards and references describe EC characteristics and possible uses both in the design stage and in other building life cycle stages; at the same time, they point out a need for building CO2-equivalent emissions calculation methods. The paper deals with research titled “decarbonisation tools” to provide common definitions and develop an EC accounting method. The main phases of the investigation work are reported. Further, the paper describes some future developments and outlooks for making EC an indicator understandable to several stakeholders of the construction sector as well as user-friendly from the early stage of the design process

Progetto locale ecocompatibile di filiera di prodotto:pannelli isolanti innovativi in lana di pecora. A sustainable building product: advanced insulation panels obtained by recycling regional sheep's wool

The article deal with an ongoing research aimed at developing an advanced self-bearing panel, fitted for thermal and acoustic insulation of buildings, derived from the reuse and recycling of local sheep wool. The development of a supply chain of environmentally friendly products (a self bearing panel made of 100% wool) encourages, on the one hand, the use of a material so far classified in Italy as special waste and, on the one other, provides new opportunities for a sheep farming that it is now going through an economic recession, with positive effects on the mountain and the hill landscap

Analysis of CO2 Post-combustion Capture in Coal-fired Power Plants Integrated with Renewable Energies☆

Abstract In light of the current consumption and proven reserves of fossil-fuels, it is beyond doubt that they will continue to play an important role in the World energy scenario, making crucial the implementation of solutions for carbon emissions reduction. One promising option for decarbonising existing or new-build power plants is post-combustion capture by chemical absorption. Besides its environmental benefits, this process causes a decrease of power plant capacity, due to heat and electricity requirement of CO 2 capture and compression systems. A possible way to overcome this drawback is the use of auxiliary systems based on renewable technologies. In this paper two options for integrating renewable energies into a coal-fired power plant with CO 2 post-combustion capture are investigated. The first one envisages the use of an auxiliary biomass boiler, providing an additional power capacity, besides satisfying the CO 2 capture heat requirement. In the second option, a concentrating solar power (CSP) system is used to meet part of regeneration heat duty, in place of steam extraction from the main power plant or steam production by a biomass boiler. The study will assess the effect of renewable source availability and energy conversion efficiency on the design of the auxiliary power unit, as well as on the energy performances of coal-fired power plant retrofitted with CO 2 capture

The Generalised Born Oscillator and the Berry-Keating Hamiltonian

In this study, we introduce and investigate a family of quantum mechanical models in 0+1 dimensions, known as generalized Born quantum oscillators. These models represent a one-parameter deformation of a specific system obtained by reducing the Nambu-Goto theory to 0+1 dimensions. Despite these systems showing significant similarities with $\mathrm{T}\overline{\mathrm{T}}$-type perturbations of two-dimensional relativistic models, our analysis reveals their potential as interesting regularizations of the Berry-Keating theory. We quantize these models using the Weyl quantization scheme up to very high orders in $\hbar$. By examining a specific scaling limit, we observe an intriguing connection between the generalized Born quantum oscillators and the Riemann-Siegel $\theta$ function.Comment: 23+16 pages; 8 figures; Published versio