1,340,642 research outputs found
Adapting structuration theory to understand the role of reflexivity: Problematization, clinical audit and information systems
This paper is an exploratory account of the further development and application of a hybrid framework,
StructurANTion, that is based on Structuration Theory and Actor Network Theory (ANT). The use of social
theories in general and their use in information systems (IS) research in particular is explored leading to
the use of the framework to examine the concept of what are termed humanchine networks in the context
of clinical audit, within a healthcare Primary Care Trust (PCT). A particular focus is on the manner in which
information systems-based reflexivity contributes to both entrenching a networks’ structurated order as
well as contributing to its emancipatory change. The case study compares clinic-centric and patientcentric
audit and seeks to further extend the understanding of the role of information and information
systems within structurated humanchine activity systems. Conclusions indicate that the use of more
socially informed IS methods and approaches can incorporate more emancipatory ideals and lead to
greater adoption and usage of more relevant and useful clinical information systems and practices
Explanation and trust: what to tell the user in security and AI?
There is a common problem in artificial intelligence (AI) and information security. In AI, an expert system needs to be able to justify and explain a decision to the user. In information security, experts need to be able to explain to the public why a system is secure. In both cases, the goal of explanation is to acquire or maintain the users' trust. In this paper, we investigate the relation between explanation and trust in the context of computing science. This analysis draws on literature study and concept analysis, using elements from system theory as well as actor-network theory. We apply the conceptual framework to both AI and information security, and show the benefit of the framework for both fields by means of examples. The main focus is on expert systems (AI) and electronic voting systems (security). Finally, we discuss consequences of our analysis for ethics in terms of (un)informed consent and dissent, and the associated division of responsibilities
Describing the complexity of systems: multi-variable "set complexity" and the information basis of systems biology
Context dependence is central to the description of complexity. Keying on the
pairwise definition of "set complexity" we use an information theory approach
to formulate general measures of systems complexity. We examine the properties
of multi-variable dependency starting with the concept of interaction
information. We then present a new measure for unbiased detection of
multi-variable dependency, "differential interaction information." This
quantity for two variables reduces to the pairwise "set complexity" previously
proposed as a context-dependent measure of information in biological systems.
We generalize it here to an arbitrary number of variables. Critical limiting
properties of the "differential interaction information" are key to the
generalization. This measure extends previous ideas about biological
information and provides a more sophisticated basis for study of complexity.
The properties of "differential interaction information" also suggest new
approaches to data analysis. Given a data set of system measurements
differential interaction information can provide a measure of collective
dependence, which can be represented in hypergraphs describing complex system
interaction patterns. We investigate this kind of analysis using simulated data
sets. The conjoining of a generalized set complexity measure, multi-variable
dependency analysis, and hypergraphs is our central result. While our focus is
on complex biological systems, our results are applicable to any complex
system.Comment: 44 pages, 12 figures; made revisions after peer revie
Optimal Control for Open Quantum Systems: Qubits and Quantum Gates
This article provides a review of recent developments in the formulation and
execution of optimal control strategies for the dynamics of quantum systems. A
brief introduction to the concept of optimal control, the dynamics of of open
quantum systems, and quantum information processing is followed by a
presentation of recent developments regarding the two main tasks in this
context: state-specific and state-independent optimal control. For the former,
we present an extension of conventional theory (Pontryagin's principle) to
quantum systems which undergo a non-Markovian time-evolution. Owing to its
importance for the realization of quantum information processing, the main body
of the review, however, is devoted to state-independent optimal control. Here,
we address three different approaches: an approach which treats dissipative
effects from the environment in lowest-order perturbation theory, a general
method based on the time--evolution superoperator concept, as well as one based
on the Kraus representation of the time-evolution superoperator. Applications
which illustrate these new methods focus on single and double qubits (quantum
gates) whereby the environment is modeled either within the Lindblad equation
or a bath of bosons (spin-boson model). While these approaches are widely
applicable, we shall focus our attention to solid-state based physical
realizations, such as semiconductor- and superconductor-based systems. While an
attempt is made to reference relevant and representative work throughout the
community, the exposition will focus mainly on work which has emerged from our
own group.Comment: 27 pages, 18 figure
Nonadditive conditional entropy and its significance for local realism
Based on the form invariance of the structures given by Khinchin's axiomatic
foundations of information theory and the pseudoadditivity of the Tsallis
entropy indexed by q, the concept of conditional entropy is generalized to the
case of nonadditive (nonextensive) composite systems. The proposed nonadditive
conditional entropy is classically nonnegative but can be negative in the
quantum context, indicating its utility for characterizing quantum
entanglement. A criterion deduced from it for separability of density matrices
for validity of local realism is examined in detail by employing a bipartite
spin-1/2 system. It is found that the strongest criterion is obtained in the
limit q going to infinity.Comment: 12 pages, 1 figur
A design theory for e-service environments: The interoperability challenge
The delivery of e-services across organizational boundaries poses a number of issues in terms of design of inter-organizational systems that support service delivery effectively. In this context interoperability emerges as a mandatory requirement for the design of Information Technology (IT) platforms supporting collaborative e-service environments. In this paper we address this issue by presenting a design theory for IT platforms supporting e-services based on both a deep understanding of the interoperability concept and a design research approach. Through the analysis of a cooperation framework developed in the context of an EU funded project, we instantiate the theory by providing the concrete example of a solution addressing this design problem. © 2012 Springer-Verlag GmbH Berlin Heidelberg.The delivery of e-services across organizational boundaries poses a number of issues in terms of design of inter-organizational systems that support service delivery effectively. In this context interoperability emerges as a mandatory requirement for the design of Information Technology (IT) platforms supporting collaborative e-service environments. In this paper we address this issue by presenting a design theory for IT platforms supporting e-services based on both a deep understanding of the interoperability concept and a design research approach. Through the analysis of a cooperation framework developed in the context of an EU funded project, we instantiate the theory by providing the concrete example of a solution addressing this design problem. © 2012 Springer-Verlag GmbH Berlin Heidelberg.Monograph's chapter
Ecological Theory of Language Acquisition
This poster outlines an Ecological Theory of Language Acquisition (ETLA). The theory views the early phases of the language acquisition process as an emergent consequence of the interaction between the infant and its linguistic environment. The newborn infant is considered to be linguistically and phonetically naïve but endowed with the ability to register a wide range of multi-sensory inputs along with the ability to detect similarity between the multi-sensory stimuli it is exposed to. The initial steps of the language acquisition process are explained as unintended and inevitable consequences of the infant’s multisensory interaction with the adult.
The theoretical model deriving from ETLA is tested using the experimental data presented in the two additional contributions from our research team (Gustavsson et al, “Integration of audiovisual information in 8-months-old infants”; Lacerda, Marklund et al. “On the linguistic implications of context-bound adult-infant interactions”). The generality of the ETLA’s concept is likely to be of significance for a wide range of scientific areas, like robotics, where a central issue concerns addressing general problems of how organisms or systems might develop the ability to tap on the structure of the information embedded in their operating environments
Entwinement and the emergence of spacetime
It is conventional to study the entanglement between spatial regions of a
quantum field theory. However, in some systems entanglement can be dominated by
"internal", possibly gauged, degrees of freedom that are not spatially
organized, and that can give rise to gaps smaller than the inverse size of the
system. In a holographic context, such small gaps are associated to the
appearance of horizons and singularities in the dual spacetime. Here, we
propose a concept of entwinement, which is intended to capture this fine
structure of the wavefunction. Holographically, entwinement probes the
entanglement shadow -- the region of spacetime not probed by the minimal
surfaces that compute spatial entanglement in the dual field theory. We
consider the simplest example of this scenario -- a 2d conformal field theory
(CFT) that is dual to a conical defect in AdS3 space. Following our previous
work, we show that spatial entanglement in the CFT reproduces spacetime
geometry up to a finite distance from the conical defect. We then show that the
interior geometry up to the defect can be reconstructed from entwinement that
is sensitive to the discretely gauged, fractionated degrees of freedom of the
CFT. Entwinement in the CFT is related to non-minimal geodesics in the conical
defect geometry, suggesting a potential quantum information theoretic meaning
for these objects in a holographic context. These results may be relevant for
the reconstruction of black hole interiors from a dual field theory.Comment: v2: Sec. 4.3 amende
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