Spatial turn / Raumforschung

Zweitveröffentlichun

Study of a MEMS-based Shack-Hartmann wavefront sensor with adjustable pupil sampling for astronomical adaptive optics

We introduce a Shack-Hartmann wavefront sensor for adaptive optics that enables dynamic control of the spatial sampling of an incoming wavefront using a segmented mirror microelectrical mechanical systems (MEMS) device. Unlike a conventional lenslet array, subapertures are defined by either segments or groups of segments of a mirror array, with the ability to change spatial pupil sampling arbitrarily by redefining the segment grouping. Control over the spatial sampling of the wavefront allows for the minimization of wavefront reconstruction error for different intensities of guide source and different atmospheric conditions, which in turn maximizes an adaptive optics system's delivered Strehl ratio. Requirements for the MEMS devices needed in this Shack-Hartmann wavefront sensor are also presented

Epistemologies of Spaces and Places: An Introduction

The article introduces a special themed issue of Theory of Science on epistemologies of spaces and places. It provides a disciplinary context of the theme and reviews some of the key arguments that led to the so-called spatial turn in social sciences and the humanities. Science studies in the broad sense have also been affected by this shift of research interest to spatial aspects of science at both micro- and macro-levels. Scientific knowledge has been subject to analyses that stress its local contingencies, mobility and dependencies on spatial arrangements. The ensuing new epistemologies require novel concepts or reconsideration of the older terms, such as universality or objectivity

Quantum Singularities Around a Global Monopole

The behavior of a massive scalar particle on the spacetime surrounding a monopole is studied from a quantum mechanical point of view. All the boundary conditions necessary to turn into self-adjoint the spatial portion of the wave operator are found and their importance to the quantum interpretation of singularities is emphasized.Comment: 5 pages, revte

'“A strange enough region wherein to wander and muse": Mapping Clerkenwell in Victorian Popular Fictions'

Drawing on the work of Bertrand Westphal, this essay attempts to perform a geocritical reading of the London district of Clerkenwell. After discussing the spatial turn in the Humanities and introducing a range of spatial critical approaches, the essay “maps” literary Clerkenwell from the perspectives of genre hybridity and intertextuality, spatially articulate cartography, multifocal and historically aware public perception and potentially transgressive connection to outside areas. Clerkenwell is seen to have stimulated a range of genre fiction, including Newgate, realist, penny and slum fiction, and social exploration journalism. In much of this writing, the district was defined by its negative associations with crime, poverty, incarceration and slaughter. Such negative imageability, the essay suggests, was self-perpetuating, since authors would be influenced by their reading to create literary worlds repeating existing tropes; these literary representations, in turn, influenced readers’ perceptions of the area.Intertextual, multi-layered and polysensorial geocritical readings,the essay concludes, can producepowerful andnuanced pictures of literary placesbut also face a formidable challenge in defining an adequate geocentric corpus

Spatial practices in digital work : calling for a spatial turn in information systems research

The growing use of digital media in the workplace is shifting work to digital platforms, this study explores the role of the physical office space in modern organisations where digital work is the norm. We capture the way in which digital media modulates the production of space by tracing the physical and digital interactions of a software development team in a global IT company. Taking a performative and ontogenetic view of space we conceptualise two types of spatial practices that form distinct modulations and assemblages of features of the physical and digital environment. The first spatial practice modulates space to support recurrent work activities, while the second spatial practice modulates space to support ephemeral and focused work activities. This study contributes to the IS literature with a conceptual basis to study the interconnected nature of physical space in digital work in modern workplace settings. It calls for greater attention to space as a performative and constitutive element of digital work in information systems research

Horizontal mergers in the circular city: a note

Two-firm horizontal Cournot mergers give rise to multi-plant firms in spatial markets. We study location equilibria on the circle for competition between a two-store merged entity and one then two single-store competitors. Several results turn up. First of all, we get equilibrium location patterns that could not have been obtained on the segment. Secondly, we investigate the profitability of such mergers and find that they turn out to be unprofitable much earlier.circular city

Collective Current Rectification

We consider a network of coupled underdamped ac-driven dynamical units exposed to a heat bath. The topology of connections defines the absence/presence of certain spatial symmetries, which in turn cause nonzero/zero value of a mean dc-output. We discuss dynamical mechanisms of the rectification and identify dc-current reversals with synchronization/desynchronization transitions in the network dynamics.Comment: 3 fig

Spatial Theorizing in Comparative and International Education Research

The authors argue for a critical spatial perspective in comparative and international education. We briefly summarize how time and space have been conceptualized within our field. We then review mainstream social science literature that reflects a metanarrative, which we critique for contributing to false dichotomies between space and place and oversimplified views of the relationship between the global and the local. We present some of the key ideas associated with the “spatial turn,” including a relational understanding and productive capacity of space. In the final part of this article, we analyze the significance of new spatial theorizing for comparative and international education by reviewing examples of both comparative and educational researchers who are engaging with critical spatial theorizing. We argue that a possible way to confront binary thinking about space and place is by shifting attention to the relational conceptions of space, through analyses of networks, connections, and flows.Fil: Larsen, Marianne A.. No especifica;Fil: Beech, Jason. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin