A comprehensive analysis of time influence on floating floors: effects on acoustic performance and occupants\u2019 comfort

Impact noise is increasingly becoming an important issue both in terms of technologies for its reduction and in terms of its perception inside buildings. In fact, a high level of noise clearly affects indoor comfort and liveability of confined spaces. For this reason, this study focuses on the influence which the screed static load has over time on the resilient material of a floating floor and on its final performance. Five different types of resilient materials have been tested for five years and the results are analysed in terms of material type, surface contact and thickness variation, dynamic stiffness measured on 8 different time steps and its application on 6 different bare floors. Obtained parameters values are therefore studied in terms of perceived comfort and compliance with 31 European countries regulations limits. Results clearly show that time has a paramount influence on all types of resilient materials (with the exception of one) in all configurations and that complete floor selection, in time, can greatly change perceived indoor living comfort and compliance with the limits imposed by laws

Exploring supply chain finance along different supply chain stages: a case-based research in the agri-food industry

PurposeSince 2008's financial crisis, attention toward supply chain finance (SCF) has increased. However, most research investigates SCF considering single supply chain (SC) stages or buyer-supplier dyads and focuses on a single SCF solution. It is important to see how different solutions are adopted at different SC stages, by actors with different financing needs. This study aims to analyze SCF at different SC stages, to understand why different solutions are implemented at different SC stages and the contingency factors (regulation, SC stage, product category and size) influencing their adoption. Design/methodology/approachThe paper is based on multiple exploratory case studies in the Italian agri-food industry, considering firms distributed at different SC stages and adopting multiple SCF solutions. The paper exploits a contingent approach (Sousa and Voss, 2008) to analyze how contingent factors influence SCF adoption at different SC stages. FindingsFindings explain how and why different SC stages (producer, cooperative, processor and retailer) implement different SCF solutions (reverse factoring, dynamic discounting, inventory finance and Minibond), describing contingency variables' impact on their adoption. Originality/valueTo the best of the authors' knowledge, the research is original in its description of SCF at different SC stages, considering different SC actors' drivers and barriers, and questioning the importance of a coordinated approach in SCF adoption along an entire SC. Moreover, the paper adopts a contingent approach, contributing to SCF research, seldomly based on theoretical lenses

On the use of the transfer matrix method to evaluate sound insulation in complex building partitions

The transfer matrix method (TMM) represents a powerful tool to investigate wave propagation through different media, which could be particularly suitable to compute sound transmission through building partitions. Even though layered structures can be easily modelled by using the TMM approach, it is not always easy to determine the elastic properties of each layer the partitions is made of. Traditional partitions, generally made in masonry with clay or concrete bricks coupled together with mortar joints, are inhomogeneous and anisotropic structures whose elastic properties are difficult to measure. Again, cross-laminated timber (CLT) panels, due to their peculiar substructure, might exhibit a highly orthotropic behaviour. A homogenisation approach, based on a minimization algorithm of the transmission loss (TL) of the bare structure, is proposed in this paper. It allows to consider inhomogeneous or anisotropic materials as an equivalent elastic solid described by effective frequency-depended elastic properties. The reliability of this approach is validated by comparing the TL of different building partitions computed using the TMM with the experimental sound insulation determined by means of laboratory measurements

Sound absorption performance of sustainable foam materials: Application of analytical and numerical tools for the optimization of forecasting models

Traditional models used to predict acoustic properties of poroelastic materials are usually applied to fibrous layers or polyurethane foams. However, for new materials like complex cellular foams these procedures may not be applied due to the different cell microstructure. To this aim, the sound absorbing properties of novel sustainable foam materials are investigated as a function of the nature and loading of waste powders and their effects on the microstructure and the acoustic properties. The foams are prepared from naturally occurring alginates that are in situ polymerized. The morphology and the acoustic properties of the foam-cells appear linked to the particle size distribution of the starting powder. Determination of the parameters of Johnson\u2013Champoux\u2013Allard acoustic model (tortuosity, viscous characteristic length, thermal characteristic length, porosity and flow resistivity) was performed using five different forecasting methods, including traditional analytical model for fibrous materials as well as inverse procedure. A new procedure for tortuosity computation of foam is proposed and validated. Transfer Matrix Method calculation of the absorption coefficient was performed and compared with the experimental data, in order to assess the validity of the model. Indirect method technique is demonstrated to be dependent on experimental measurement of thermal characteristic length

Cardiogenic Shock in Obstructive Hypertrophic Cardiomyopathy Plus Apical Ballooning: Management With VA-ECMO and Myectomy

A patient with known obstructive hypertrophic cardiomyopathy developed worsening left ventricular outflow tract obstruction, severe mitral regurgitation, and apical ballooning leading to cardiogenic shock, a combination in which treatment of each component could worsen the others. Emergency veno-arterial extracorporeal membrane oxygenation, levosimendan, and noradrenaline transiently restored adequate systemic perfusion and gas exchange. Surgical myectomy offered a more definitive solution. (Level of Difficulty: Intermediate.

Utilização de marcadores moleculares na seleção assistida para tolerância ao alumínio em sorgo.

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