With brake squeal being most prevalent Noise Vibration and Harshness (NVH) issue in modern vehicles, this paper presents an improved methodology for brake squeal propensity prediction at the design stage. The research established four clearly defined "Stages" in conducting Finite Element (FE) squeal analyses, describing crucial input data, modelling procedures, outputs and results validations. Stage 1 deals with freefree modal characteristics of individual brake components and their material characteristics. Stage 2 combines individual parts, conducting Brake Assembly Mechanical FE Analyses. Stage 3 concentrates on fully Coupled Thermo-mechanical FE Analyses, and the concluding Stage 4 focuses on Brake Assembly Stability Analyses. Validations proved that very accurate predictions are possible, but the geometries, material characteristics and established modelling procedures must be strictly followed. Material characteristics were most prone to introduce discrepancies with measured values. 'Generic' values are found to be unacceptable and conducting own measurements was necessary, in particular for the friction material, whose anisotropic properties have been measured in detail, leading to high accuracy in predicting pad natural modes and frequencies. In Stage 4 the stability analyses of the full brake assembly were based on the Complex Eigenvalue Analysis (which included thermal aspects), with the sign of the real part giving an indication of stability and the imaginary part defining the frequency of the unstable mode. Instabilities and frequencies predicted match well with the values measured in dynamometer tests, clearly demonstrating the influence of thermal effects. The final output of the procedures described in this Paper is a validated 3D thermo-mechanical FE NVH brake assembly model in which natural frequencies and modes, instabilities and contributing factors can be predicted at any time during a brake application.

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The paper gives a critical account of the recent Italian debate on Commons concentrating on some theoretical problems, with reference to two different components: the economic research on the Commons, the juridical research on the property nature of Commons. It then puts them in parallel with the social demands arisen, articulated around the buzzword “Commons”. The mutual relationship among these components is analysed, stressing the generative aspects of the encounter between scholarship on one hand and the social, discursive use of the Commons concept on the other hand. Finally a research agenda based on the results of such analysis is proposed in order to re-compose the mentioned duality and partially overcome the difficulties that today harness the Italian debate on the Commons and its possible applications in urban planning.

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