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Purpose: Ceramic facing bricks are construction materials used to produce an attractive aspect to building walls and provide protection from external exposure. The purpose of this research is twofold: first, to conduct a comparative cradle-to-gate life cycle assessment (LCA) to evaluate environmental impacts of manufacturing options available for obtaining different colours and appearance of facing bricks, and second, basing on LCA results, to examine recent literature and environmental product declaration (EPD) items (ISO 14025:2006) to verify if current EU best available techniques (BATs) in ceramic manufacturing industry that are dated 2007 are still relevant today, especially in the light of current technological progresses. The considered manufacturing options are necessary to obtain three different final appearances of the facing brick. In the first option, the brick is left in its natural colour. The second and third options include the applications of two type of coatings, which are the engobing and the glazing solutions. Methods: The analysis of life cycle stages was performed according to the cradle-to-gate approach (ISO 14040:2006b UNI EN ISO 14040:2006—environmental management-life cycle assessment-principles and framework; ISO 14044:(2006c) ISO 14044:2006/Amd 1:2017 environmental management-life cycle assessment-requirements and guidelines-amendment 1/Amd 1:2017). The software tool used is SimaPro® version 9.0.0.31, and inventories are based on ecoinvent v.3.5. LCA was performed basing on ceramic BATs and literature data, assuming the German energy mix. The consistency of results and the evaluation of ceramic BATs were discussed on the basis of a comparison of results with recent LCA studies and application of sensitivity analysis. Results and discussion: One of the results of this study is that coating options entail significant environmental impacts. As instance, the application of both engobe and glaze coatings increases the global warming potential (GWP) up to 7.2% and human toxicity (HT) up to 143.1%. Finally, results confirm the importance of implementing existing saving technologies for the firing stage, being the main contributor to climate change among production activities. Moreover, environmental impacts that have been obtained assessing the product life cycle with BATs are generally higher if compared with current literature, in a range up to + 240%. Conclusions: In conformity with ISO standards, this LCA analyses the potential environmental impacts of facing bricks, considering three manufacturing options. The evidences provided by this study demonstrate the importance to include coating materials in LCA studies involving facing bricks. Finally, results let the authors to conclude that a revision of BATs is necessary in order to update technology requirements that are contained in the document to the current state of the art. [ABSTRACT FROM AUTHOR]

This paper attempts an investigation into the features of ecological fallacy in the context of estimation of voter transitions between two elections. After reviewing some theoretical findings from a statistical point of view, we discuss two tools for checking whether bias is present: (1) fitting models with covariates; (2) comparing the standard errors of transition probabilities computed under ideal conditions against those based on bootstrap methods. Concerning the effect of covariates, we describe two different data generating mechanisms, depending on whether voting decisions are affected by variables measured at the (1) aggregate or (2) the individual level. By theoretical arguments and empirical evidence, we show that, while modelling the effect of covariates removes bias in the first case, it may fail in the second because only aggregate level covariates are usually available. Our investigation relies on the analysis of real and artificial data sets: the latter are obtained by a computer software which mimics voting behaviour and is such that, artificial electoral data with designed size and direction of ecological bias can be produced. An application to a recent election in the city of Turin is also used to illustrate our methodology and findings. [ABSTRACT FROM AUTHOR]

RAMS is an acronym for reliability, availability, maintainability and safety. These four properties concern the application of important methodologies to design and manage complex systems. In the present research, starting from the analysis of several literature reliability allocation techniques, a reliability allocation method has been implemented called analytic critical flow method (ACFM). Critical flow method is a reliability allocation method for series-parallel configurations, based on failure analysis of each unit of the system. The new approach is based on critical flow method, whose results are matched with the analytic hierarchy process multicriteria method. The result is a dynamic model that combines the advantages of the allocation method and the multicriteria approach. The need to develop the ACFM is the outcome of a careful analysis of the current military and commercial approaches. In particular, no literature method takes into account to assign a different level of significance (weight) to the different units of the system, simultaneously to the considered factors. The proposed approach has been applied and compared with other traditional methods on an aerospace prototype (series-parallel configuration), where the reliability allocation process is rigorous. The results demonstrate the effectiveness of the new approach and its ability to overcome the criticalities highlighted in literature. [ABSTRACT FROM AUTHOR]

The primary aim of the study was to adopt QOLIBRI (quality of life after brain injury) questionnaire in a proxy version (Q-Pro), i.e., to use caregivers for comparison and to evaluate whether TBI patients' judgment corresponds to that of their caregivers since the possible self-awareness deficit of the persons with TBI. A preliminary sample of 19 outpatients with TBI and their proxies was first evaluated with the Patient Competency Rating Scale to assess patients' self-awareness; then they were evaluated with the QOLIBRI Patient version (Q-Pt) and a patient-centered version of the Q-Pro. Subsequently, 55 patients and their caregivers were evaluated using the patient-centered and the caregiver-centered Q-Pro versions. Q-Pt for assessing Quality of Life (QoL) after TBI, as patients' subjective perspective and Q-Pro to assess the QoL of patients as perceived by the caregivers. The majority of patients (62.2%) showed better self-perception of QoL than their proxies; however, patients with low self-awareness were less satisfied than patients with adequate self-awareness. Low self-awareness does not impair the ability of patients with TBI to report on satisfaction with QoL as self-perceived. [ABSTRACT FROM AUTHOR]

The success of a company depends on customer's satisfaction: quality, price, and service. These three goals depend in particular on R.A.M.S. characteristics: reliability, availability, maintainability, and safety. In the last few years, in order to guarantee high standards of reliability and maintainability, new methodologies and techniques have been developed to estimate the R.A.M.S. targets. In particular, the reliability target represents both the starting and the ending point of R.A.M.S. analysis. The design of the reliability target of a system is a crucial aspect of reliability analysis, as it affects the performance of the system and components. This paper aims to develop a new approach called 'IFM Target,' to define the reliability target for complex systems through the integrated factors method, to combine the advantages of usually used approaches, and to overcome some criticalities highlighted in a careful literature analysis. The proposed method has been applied on a sintering system. The results show the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The ever-increasing complexity of production systems, together with the need to obtain efficient processes with limited costs, has led companies to develop custom tools for process control and management. Even for risk assessment, the traditional models often are overcome by methods that are best suited to specific needs. In this context, the aim of this paper was to propose a new model, which we call the global safety improve risk assessment (G-SIRA). This model can classify risks and identify corrective actions that allow the best risk reduction at the lowest cost. The proposed model, which is based on improvements to previous research, uses the analytic hierarchy process approach to develop a valid and simple tool for risk management. The G-SIRA method has been tested in a real-world application, i.e., it was applied to all of the processes of a textile company, and the results were compared with those obtained from the classical approach failure mode, effects, and criticality analysis. The comparison clearly showed the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

The reliability of a system during operation can be expressed quantitatively through different time functions. Mathematical procedures and statistical laws allow to assess the precise analytical relations between these functions. Referring to a generic system or component is a common experience that its duration in-service is not predictable in a deterministic way. This consideration identifies the lifetime (or time to failure) of the component as a continuous random variable, susceptible to a statistical description, whose estimate is crucial in the design phase, or in any case before the commissioning of equipment. In a second stage, the actual values of reliability must be compared with the forecast values arising from the theoretical statistical model used. This comparison allows assessment of the goodness-of-fit level and the confidence level of the prediction model, in order to validate it for any future equipment redesigns or for similar equipment. In this context, the present work is aimed at identifying the most appropriate statistical tools for the comparison above, and then to assess the reliability of the forecast data, compared to the real performance of a reliability system. For this purpose, a literature analysis was conducted, with a dual purpose: The identification of statistical models most commonly used to describe the reliability function of a system; to provide a choice of appropriate indicators and effective tests for assessing the confidence of the statistical models for reliability scopes. The models identified were then applied, as an example, to the real case of a catalytic cracking catalyst with the fluidized bed of a petrochemical plant. The results obtained from the case study, discussed in the final section of the work, offer many points of comparison between the various statistical models as well as a first overview of their reliability. [ABSTRACT FROM AUTHOR]

This paper introduces some new models of ecological inference within the context of estimation of voter transitions across elections. In particular, we assume that voters of a given party in a given occasion may be split into two latent types: faithful voters, who will certainly vote again for the same party and movers, who will reconsider their choice. Our models allow for unobserved heterogeneity across polling stations both in the weights of the two latent classes within each party and also when modelling the choice of unfaithful voters. Different ways of modelling the unobserved heterogeneity are considered by exploiting properties of the Dirichlet-multinomial distribution and the Brown Payne model of voting transitions can be seen as a special case within the class of models presented here. We discuss pseudo-maximum likelihood estimation and present an application to recent elections in Italy. [ABSTRACT FROM AUTHOR]

The assumptions underlying item response theory (IRT) models may be expressed as a set of equality and inequality constraints on the parameters of a latent class model. It is well known that the same assumptions imply that the parameters of the manifest distribution have to satisfy a more complicated set of inequality constraints which, however, are necessary but not sufficient. In this paper, we describe how the theory for likelihood-based inference under equality and inequality constraints may be used to test the underlying assumptions of IRT models. It turns out that the analysis based directly on the latent structure is simpler and more flexible. In particular, we indicate how several interesting extensions of the Rasch model may be obtained by partial relaxation of the basic constraints. An application to a data set provided by Educational Testing Service is used to illustrate the approach. [ABSTRACT FROM AUTHOR]