An analytical insight into the buckling paradox for circular cylindrical shells under axial and lateral loading

A large number of authors in the past have concluded that the flow theory of plasticity tends to overestimate significantly the buckling load for many problems of plates and shells in the plastic range, while the deformation theory generally provides much more accurate predictions and is consequently used in practical applications. Following previous numerical studies by the same authors focused on axially compressed cylinders, the present work presents an analytical investigation which comprises the broader and different case of nonproportional loading. The analytical results are discussed and compared with experimental and numerical findings and the reason for the apparent discrepancy on the basis of the so-called “buckling paradox” appears once again to lay in the overconstrained kinematics on the basis of the analytical and numerical approaches present in the literature

Numerical And Analytical Analyses Of High-Strength Steel Cellular Beams: A Discerning Approach

The behaviour of cellular beams made from normal and high strength steel with various geometries is investigated through a large number of finite element analyses and a simple mechanical model for the Web-Post Buckling (WPB) failure is developed and analysed in order to highlight the factors which influence its occurrence and development for both normal and High-Strength (HS) steels. The performed FE analyses and the proposed modelling, once calibrated, allow to shed some light on the characteristics of the phenomenon and to provide the basis of a reliable design method to predict shear buckling of web-post of cellular beams made both of mild and HS steel

The Postcolonial Writer in Performance: J. M. Coetzee’s Summertime

This essay focuses on the elaboration of postcolonial literature as an event emerging from the interaction among the many and diverse agencies which allow the postcolonial work to come into being. This formulation both highlights the repetition of tropes in postcolonial literature and the variations to the tropes themselves, which can become ethically and politically relevant by creating an interruption in accepted notions of what a postcolonial work should sound like. Following this lead, the essay will outline a methodological approach which interprets the literary work as a performative act in the complex nexus of discourses constituting the postcolonial writer as a figure of the global collective imaginary, taking as case study J. M. Coetzee’s work with particular focus on his Nobel Prize lecture and the third instalment of his memoir series, Summertime (2009). His work, together with others, is taken as a symptom of how public lectures and statements, together with the literary work proper, have all become an expression of the writer’s own performativity as a writer; while these phenomena have an impact on literature as a whole, the essay focuses on the postcolonial writer figure as historically endowed with what Kobena Mercer has famously termed “the burden of representation.

The Dance of the Dead Rhino: William Kentridge’s Magic Flute

The article offers a reading of the staging of The Magic Flute by visual artist William Kentridge, focusing on his introduction of the rhino in the visual landscape of the opera as symbol for the silenced subject of violence. Operatic tradition has always been concerned with the staging of death, in particular with the death of its female protagonists, and recent scholarship has highlighted the complicity of the genre with the ideology of Western patriarchy and colonial violence. In this light, Kentridge's appropriation stages Mozart's opera as both voice of colonial Europe and place of resistance for the postcolonial artist. Kentridge moves the setting of the opera to colonial Africa, and the Flute becomes haunted with the massacre of the Herero people in South West Africa by the German army led by general von Trotha (1904-1907). The African white rhino, a species under the threat of extinction, works in this work as proxy for the missing corpses of the Herero people; in its being subject to humiliation and ruthless murder, it recalls Judith Butler's recent attempt at a different categorization of human life as both a continuous exposure to violence and what can be mourned after death. With its silence among the powerful sounds of Mozart's opera, the body of the dead, dancing rhino stands at the centre of Kentridge's work, which becomes a ceremony of mourning where the Western canon can be made to "resonate differently" (Trinh T. Minh-ha).&nbsp

Writing “so raw and true”: Blogging in Chimamanda Ngozi Adichie’s Americanah

This essay aims at tracing the intersection between literary production and multimedia textuality in the case of postcolonial writing through an analysis of Chimamanda Ngozi Adichie’s recent novel Americanah (2013). Here the main character Ifemelu, after leaving her native Lagos to study in the US, becomes famous as a blogger on racial issues from the point of view of a non-American black. Starting from Sandra Ponzanesi’s The Postcolonial Cultural Industry, the analysis of the novel takes into account recent debates on the public role of postcolonial writers, as the blog reflects Adichie’s own role in contemporary media and situates the novel in the global landscape of Afropolitanism and its predicaments.  Blog entries inhabit the novel from its early pages, and blogging intersects fiction and contaminates it with social commentary. With its interweaving of creative writing and opinion making, novel and blog, Americanah comments on the public role of the writer and its viral exposure, offering a poignant example of the mutation of narrative forms in the information age.Questo contributo indaga l’intreccio tra produzione letteraria e testualità multimediali nella scrittura postcoloniale attraverso l’analisi del recente romanzo di Chimamanda Ngozi Adichie Americanah (2013). Qui la protagonista Ifemelu, trasferitasi da Lagos negli Stati Uniti, apre un blog che si occupa di questioni razziali dal punto di vista di una nera non statunitense. Partendo dalle argomentazioni proposte da Sandra Ponzanesi nel suo The Postcolonial Cultural Industry (2014), l’analisi del romanzo prende in considerazione il recente dibattito sul ruolo pubblico dello scrittore postcoloniale: il blog riflette il ruolo di Adichie nei media e situa il romanzo – non senza fratture – nel panorama globale dell’Afropolitanismo. I post del blog appaiono nel romanzo dall’inizio, e la sua scrittura interseca la fiction contaminandola con un ampio commento sociale. Con il suo intreccio di scrittura creativa e d’opinione, romanzo e blog, Americanah commenta sul ruolo pubblico dello scrittore e la sua presenza ‘virale’ nei media, offrendo un esempio pregnante sul cambiamento delle forme narrative nell’era dell’informazione

An Analytical Approach to the Analysis of Inhomogeneous Pipes under External Pressure

Pipes for deep-water applications possess a diameter-to-thickness ratio in a region where failure is dominated by both instability and plastic collapse. This implies that prior to failure the compressive yield strength of the material must be exceeded, followed by ovalisation and further local yielding. This paper presents an investigation into the mechanics of this specific problem and develops an analytical approach that accounts for the effects of geometrical and material data on the collapse pressure of inhomogeneous rings under external hydrostatic pressure. The analytical expressions have been correlated to numerical and experimental test data, proving their accuracy

Le sfide della teoria: una conversazione con Fiorenzo Iuliano

Fiorenzo Iuliano è ricercatore di Lingue e letterature angloamericane presso l'Università di Cagliari. I suoi ambiti di ricerca comprendono la letteratura americana contemporanea (romanzo, graphic novel, rapporti tra letteratura e musica, Studi Culturali negli USA), gli studi di genere e gli studi sulla corporeità e la teoria letteraria. Al momento sta lavorando a uno studio sulla costruzione del mito culturale della città di Seattle negli anni Novanta

Stability Analysis of Circular Beams with Mixed-Mode Imperfections under Uniform Lateral Pressure

The elastic-plastic collapse of circular beams under uniform lateral pressure with an initial imperfection represented by a combination of different modes and amplitudes and with varying material properties is analysed from a computational viewpoint. The work is stimulated by a number of accurate experimental tests recently performed and it is found that both the initial imperfection and the material inhomogeneity along the beam axis can affect the collapse and produce a sensible variation in the carrying capacity of the structure on account of the changes between the underlying buckling modes. This can give reason for some apparently anomalous observed experimental results