A Van der Pol-Mathieu equation for the dynamics of dust grain charge in dusty plasmas

The chaotic profile of dust grain dynamics associated with dust-acoustic oscillations in a dusty plasma is considered. The collective behaviour of the dust plasma component is described via a multi-fluid model, comprising Boltzmann distributed electrons and ions, as well as an equation of continuity possessing a source term for the dust grains, the dust momentum and Poisson's equations. A Van der Pol–Mathieu-type nonlinear ordinary differential equation for the dust grain density dynamics is derived. The dynamical system is cast into an autonomous form by employing an averaging method. Critical stability boundaries for a particular trivial solution of the governing equation with varying parameters are specified. The equation is analysed to determine the resonance region, and finally numerically solved by using a fourth-order Runge–Kutta method. The presence of chaotic limit cycles is pointed out.

Cinema Lucida: Johan van der Keuken and the Meaning of Loss

Ever sceptical about the positivistic claims of ethnographic and so-called realist documentary, Johan van der Keuken’s film-making is the work of a curious, spontaneous and disorientated observer of the essential strangeness of both the foreign and the familiar, new landscapes and cities, experiences, and people. While there are various explicitly political and socially orientated films and themes across his work, it is those films and moments when what is being conveyed is a sense of him being somewhere liminal, being ‘in-between’ situations, cultures, styles and interpretations, reticent, uncertain but incorrigibly curious that constitute his most valuable contribution to documentary film aesthetics. Not surprisingly, such characteristics often come to the fore in those films where he tries to make sense of loss, the passing of lives and the legacies left behind. This article discusses questions of history and personal loss in a number of his films.

De bankencrisis van de jaren twintig

Lessen uit een lang vergeten crisis voor hedendaagse beleidsmakers en banken.

Book Review - An Architecture of Parts: Architects, Building Workers and Industrialisation in Britain 1940–1970 by Christine Wall and Architecture and the Welfare State, edited by Mark Swenarton, Tom Avermaete and Dirk van den Heuvel.

De triomf van de tiran: Triumphi als kritiekmiddel in Romeinse literatuur

Of all the rituals of ancient Rome none was more spectacular than the triumph. Scholarly attention has long been devoted to the origins and circumstances of this ritual, but lately the role of the triumph in moral discourse has also come into focus. Emperors could gain great military prestige from celebrating a triumphus, yet this prestige could (posthumously) be undermined by hostile historians and biographers who used descriptions of triumphal processions to cast unpopular emperors in a negative light. Discussing in particular the ‘bad triumphs’ of Nero, Elagabalus, and Gallienus, but also considering many other cases, this article explores how triumphal descriptions could be employed as literary weapons. Ancient authors did not hesitate to emphasize, distort, or invent certain aspects of the ritual to suit their purposes. In fact, the triumphal idiom proved such a powerful tool for the delegitimation of emperors that it was even employed to situations which did not constitute triumphal celebrations at all. Hence the cultural elite sought to control the meaning of the ritual and to establish whether emperors counted as benign rulers or tyrants.