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The open access book covers a large class of nonlinear systems with many practical engineering applications. The approach is based on the extension of linear systems theory using the Volterra series. In contrast to the few existing treatments, our approach highlights the algebraic structure underlying such systems and is based on Schwartz's distributions (rather than functions). The use of distributions leads naturally to the convolution algebras of linear time-invariant systems and the ones suitable for weakly nonlinear systems emerge as simple extensions to higher order distributions, without having to resort to ad hoc operators. The result is a much-simplified notation, free of multiple integrals, a conceptual simplification, and the ability to solve the associated nonlinear differential equations in a purely algebraic way. The representation based on distributions not only becomes manifestly power series alike, but it includes power series as the description of the subclass of memory-less, time-invariant, weakly nonlinear systems. With this connection, many results from the theory of power series can be extended to the larger class of weakly nonlinear systems with memory. As a specific application, the theory is specialised to weakly nonlinear electric networks. The authors show how they can be described by a set of linear equivalent circuits which can be manipulated in the usual way. The authors include many real-world examples that occur in the design of RF and mmW analogue integrated circuits for telecommunications. The examples show how the theory can elucidate many nonlinear phenomena and suggest solutions that an approach entirely based on numerical simulations can hardly suggest. The theory is extended to weakly nonlinear time-varying systems, and the authors show examples of how time-varying electric networks allow implementing functions unfeasible with time-invariant ones. The book is primarily intended for engineering students in upper semesters and in particular for electrical engineers. Practising engineers wanting to deepen their understanding of nonlinear systems should also find it useful. The book also serves as an introduction to distributions for undergraduate students of mathematics.

This chapter addresses the interpretations of the emerging social question in the field of post-revolutionary French liberalism. It focuses on the cholera outbreak of 1832 to describe how it fostered unprecedented and dramatic representations of urban pauperism chiefly marked by feelings of panic and distress with respect to the new "dangerous classes" brought into being by the Industrial Revolution. By analysing the pandemic crisis, the chapter shows that these subjects were initially perceived not merely as a different social class, but also – and especially – as a different "race," according to a conception exemplified by the metaphor of "new barbarians" invading the manufacturing cities. Hence, the chapter retraces a transformation whereby these initial representations of the subaltern classes based on fear and exclusion gradually gave way to the rise of social research on the subaltern classes aimed at elaborating new welfare policies as risk reduction strategies. These initiatives of social investigation are described as marking the origins of the methods and epistemology of modern social sciences, which are the focus of the following chapter.

The surging wave of indigenous politics, rights of nature, and social movements acting with rocks, rivers, glaciers, and lakes has brought to light an ecology of nonlife. Its protagonists are 'earth-beings,' geobodies that question deep-seated Western notions of personhood. Mountains in the Andes, erratic boulders, a landfill in the Swiss Alps, the sacred stones of the Standing Rock Sioux Reservation, and the works of contemporary artists who have engaged with nonlife reveal the subjectivity of beings that are not sentient and alive as biological organisms.

The questions related to waste management are not merely technical; what, how, where, and by whom becomes intrinsically political questions. This book is about the power relations in recycling, from the viewpoint of political ecology, and ecological economics.

The essay analyses the political relations between rural lordships and supralocal powers in the fourteenth and fifteenth centuries central Italy, on the base of researches carried out during the 2015 project PRIN. The areas considered are the territories of the Papal State, Tuscany and Sardinia. The essay proceeds by territorial frameworks, with the aim of bringing out the different peculiarities of each area and the most relevant common phenomena regarding the relational dynamics between the secular or ecclesiastical domain spaces and the higher powers, with particular reference to the Papacy, to the cities and sovereigns (as in the case of the Aragon Crown in the Sardinian context).