Integration algorithms of elastoplasticity for ceramic powder compaction

Inelastic deformation of ceramic powders (and of a broad class of rock-like and granular materials), can be described with the yield function proposed by Bigoni and Piccolroaz (2004, Yield criteria for quasibrittle and frictional materials. Int. J. Solids and Structures, 41, 2855-2878). This yield function is not defined outside the yield locus, so that 'gradient-based' integration algorithms of elastoplasticity cannot be directly employed. Therefore, we propose two ad hoc algorithms: (i.) an explicit integration scheme based on a forward Euler technique with a 'centre-of-mass' return correction and (ii.) an implicit integration scheme based on a 'cutoff-substepping' return algorithm. Iso-error maps and comparisons of the results provided by the two algorithms with two exact solutions (the compaction of a ceramic powder against a rigid spherical cup and the expansion of a thick spherical shell made up of a green body), show that both the proposed algorithms perform correctly and accurately.Comment: 21 pages. Journal of the European Ceramic Society, 201

Plastically-driven variation of elastic stiffness in green bodies during powder compaction. Part II: Micromechanical modelling

A micromechanical approach is set-up to analyse the increase in elastic stiffness related to development of plastic deformation (the elastoplastic coupling concept) occurring during the compaction of a ceramic powder. Numerical simulations on cubic (square for 2D) and hexagonal packings of elastoplastic cylinders and spheres validate both the variation of the elastic modulus with the forming pressure and the linear dependence of it on the relative density as experimentally found in Part~I of this study, while the dependence of the Poisson's ratio on the green's density is only qualitatively explained

Osteochondritis dissecans of the knee: Epidemiology, etiology, and natural history.

Osteochondritis dissecans of the knee is a disease that typically affects skeletally immature patients. Clinically manifested with knee pain, limping, and joint disfunction, this condition has remained misunderstood and undervalued for a long period. Although being a rare condition, its awareness is of utmost clinical interest because of the possible severe consequences it can bring when misrecognized or inadequately treated. Its etiology remains unclear and is still debated. Many theories have been proposed, including inflammation, local ischemia, subchondral ossification abnormalities, genetic factors, and repetitive mechanical microtrauma, with a likely interplay of the same. This review article aims to deliver and discuss current and up-to-date concepts on epidemiology, etiology, and natural history of this pediatric condition. Level of evidence: level V

Observation of single phonon-mediated quantum transport in a silicon single-electron CMOS transistor by RMS noise analysis

We explore phonon-mediated quantum transport through electronic noise characterization of a commercial CMOS transistor. The device behaves as a single electron transistor thanks to a single impurity atom in the channel. A low noise cryogenic CMOS transimpedance amplifier is exploited to perform low-frequency noise characterization down to the single electron, single donor and single phonon regime simultaneously, not otherwise visible through standard stability diagrams. Single electron tunneling as well as phonon-mediated features emerges in rms-noise measurements. Phonons are emitted at high frequency by generation-recombination phenomena by the impurity atom. The phonon decay is correlated to a Lorentzian $1/f^2$ noise at low frequency.Comment: 5 pages, 3 figures, submitted to AP

Accounting for Power and Resistance: the University of Ferrara under the Fascist Regime in Italy

Recognising the dynamic character of the exercise of power, this study analyses the complex interplay between power and resistance, as conceived by Foucault, after the Italian Fascists sought to subjugate all Italian universities. When the University of Ferrara, a ‘Free University’, resisted the government’s intentions, which would also have meant restricting access to higher education to working class youth, accounting practices became essential in providing justification for the government’s actions. In response, the University was forced to use accounting practices as its main form of defence. This resulted in the government having to use different tactics to achieve its final goals. If resistance is met by governments in the implementation of their programmes this may require a shift in the tactics originally employed to achieve the planned outcomes. Greater demands were placed on the funders of the University and changes were made to how the University’s performance was represented, interpreted and evaluated by the means of accounting practices. In the power struggle, accounting played different roles in the service of conflicting objectives, ranging from concealing the interested nature of political action, demonstrating the achievement of financial stability and self-sufficiency, providing legitimacy or ensuring the use of resources consistent with the aims of those who exercised power. So persuasive was the action enabled by accounting information that the State was finally able to gain control of the University without making it a ‘Kingdom University’, and hence seeming to preserve the appearance of independence almost until the end of the Fascist regime

Public value and public sector accounting research: a structured literature review

Purpose – The paper investigates the role and impact of accounting within the fragmented field of public value theory literature. Design/methodology/approach – The work develops a structured literature review and seeks to shed light on the state of public value research, with particular emphasis on the role of accounting scholarship. Findings – The lack of empirical research and the limited number of papers on accounting for the creation of public value means that accounting scholars need to address ‘theoretical stagnation’ to achieve a deeper understanding of how to govern the public value creation process. Originality/value – The paper develops the first wide-ranging structured literature review on public value accounting. It is a starting point to develop new research avenues, both in the fields of accountability/external reporting, and management accounting and performance management. Keywords: public value, performance measurement, public value accounting, structured literature review Paper type: Literature revie