Formal models for component connectors

Rutten, J.J.M.M. [Promotor]Arbab, F. [Promotor]Niqui, M. [Copromotor]Clarke, D.G. [Copromotor

Academic discourse and narratives of literacy as 'equipment for living'

In his article "Academic Discourse and Narratives of Literacy as 'Equipment for Living'" Kris Rutten discusses practices of academic discourse and argues that students entering higher education have to become part of a specific community of institutional discourse. Rutten claims that narratives of and about literacy — narratives that revolve around issues dealing with language and the acquisition of literacy — "dramatize" the tension of moving from one discourse community to another. By charting situations of "type," fictional literacy narratives can be used by students as "equipment for living" in order to reflect on confrontations and difficulties they experience in higher education. Kenneth Burke's "dramatistic pentad" is introduced as an analytical tool to study representations and interpretations of institutional discourse in fictional narratives. In a case study, the popular literacy narrative Educating Rita is analyzed and confronted with personal reflections of students. Further, Rutten discusses what can be learned from a rhetorical perspective on literacy about roles (identities) and language (institutional discourses) in higher education

Interplanetary Consequences of a Large CME

We analyze a coronal mass ejection (CME) which resulted from an intense flare in active region AR486 on November 4, 2003. The CME propagation and speed are studied with interplanetary scintillation images, near-Earth space mission data, and Ulysses measurements. Together, these diverse diagnostics suggest that the internal magnetic energy of the CME determines its interplanetary consequences.Comment: 5 pages, 9 figures, To appear in "Magnetic Coupling between the Interior and the Atmosphere of the Sun", eds. S.S. Hasan and R.J. Rutten, Astrophysics and Space Science Proceedings, Springer-Verlag, Heidelberg, Berlin, 200

Coalgebraic Modelling : Applications in Automata theory and Modal logic

Rutten, J.J.M.M. [Promotor]Venema, Y. [Copromotor]Kupke, C.A. [Copromotor

Academic Discourse and Literacy Narratives as Equipment for Living

In his article Academic Discourse and Narratives of Literacy as \u27Equipment for Living\u27 Kris Rutten discusses practices of academic discourse and argues that students entering higher education have to become part of a specific community of institutional discourse. Rutten claims that narratives of and about literacy — narratives that revolve around issues dealing with language and the acquisition of literacy — dramatize the tension of moving from one discourse community to another. By charting situations of type, fictional literacy narratives can be used by students as equipment for living in order to reflect on confrontations and difficulties they experience in higher education. Kenneth Burke\u27s dramatistic pentad is introduced as an analytical tool to study representations and interpretations of institutional discourse in fictional narratives. In a case study, the popular literacy narrative Educating Rita is analyzed and confronted with personal reflections of students. Further, Rutten discusses what can be learned from a rhetorical perspective on literacy about roles (identities) and language (institutional discourses) in higher education

SINFONI Observations of Starclusters in Starburst Galaxies

We have used ESO's new NIR IFS SINFONI during its Science Verification period to observe the central regions of local starburst galaxies. Being Science Verification observations, the aim was two-fold: to demonstrate SINFONI's capabilities while obtaining information on the nature of starclusters in starburst galaxies. The targets chosen include a number of the brighter clusters in NGC1808 and NGC253. Here we present first results.Comment: Submitted to "Adaptive Optics-Assisted Integral-Field Spectroscopy", Rutten R.G.M., Benn C.R., Mendez J., eds., May 2005, La Palma (Spain), New Astr. Re

Spectropolarimetry with CRISP at the Swedish 1-m Solar Telescope

CRISP (Crisp Imaging Spectro-polarimeter), the new spectropolarimeter at the Swedish 1-m Solar Telescope, opens a new perspective in solar polarimetry. With better spatial resolution (0.13") than Hinode in the Fe I 6302 A line and similar polarimetric sensitivity reached through postprocessing, CRISP complements the SP spectropolarimeter onboard Hinode. We present some of the data which we obtained in our June 2008 campaign and preliminary results from LTE inversions of a pore containing umbral dots.Comment: To appear in "Magnetic Coupling between the Interior and the Atmosphere of the Sun", eds. S.S. Hasan and R.J. Rutten, Astrophysics and Space Science Proceedings, Springer-Verlag, Heidelberg, Berlin, 200

Horizontal supergranule-scale motions inferred from TRACE ultraviolet observations of the chromosphere

We study horizontal supergranule-scale motions revealed by TRACE observation of the chromospheric emission, and investigate the coupling between the chromosphere and the underlying photosphere. A highly efficient feature-tracking technique called balltracking has been applied for the first time to the image sequences obtained by TRACE (Transition Region and Coronal Explorer) in the passband of white light and the three ultraviolet passbands centered at 1700 {\AA}, 1600 {\AA}, and 1550 {\AA}. The resulting velocity fields have been spatially smoothed and temporally averaged in order to reveal horizontal supergranule-scale motions that may exist at the emission heights of these passbands. We find indeed a high correlation between the horizontal velocities derived in the white-light and ultraviolet passbands. The horizontal velocities derived from the chromospheric and photospheric emission are comparable in magnitude. The horizontal motions derived in the UV passbands might indicate the existence of a supergranule-scale magnetoconvection in the chromosphere, which may shed new light on the study of mass and energy supply to the corona and solar wind at the height of the chromosphere. However, it is also possible that the apparent motions reflect the chromospheric brightness evolution as produced by acoustic shocks which might be modulated by the photospheric granular motions in their excitation process, or advected partly by the supergranule-scale flow towards the network while propagating upward from the photosphere. To reach a firm conclusion, it is necessary to investigate the role of granular motions in the excitation of shocks through numerical modeling, and future high-cadence chromospheric magnetograms must be scrutinized.Comment: 5 figures, accepted by Astronomy & Astrophysic

The Quiet-Sun Photosphere and Chromosphere

The overall structure and the fine structure of the solar photosphere outside active regions are largely understood, except possibly important roles of a turbulent near-surface dynamo at its bottom, internal gravity waves at its top, and small-scale vorticity. Classical 1D static radiation-escape modelling has been replaced by 3D time-dependent MHD simulations that come closer to reality. The solar chromosphere, in contrast, remains ill-understood although its pivotal role in coronal mass and energy loading makes it a principal research area. Its fine structure defines its overall structure, so that hard-to-observe and hard-to-model small-scale dynamical processes are the key to understanding. However, both chromospheric observation and chromospheric simulation presently mature towards the required sophistication. The open-field features seem of greater interest than the easier-to-see closed-field features.Comment: Accepted for special issue "Astrophysical Processes on the Sun" of Phil. Trans. Royal Soc. A, ed. C. Parnell. Note: clicking on the year in a citation opens the corresponding ADS abstract page in the browse

Testing the Equivalence of Regular Languages

The minimal deterministic finite automaton is generally used to determine regular languages equality. Antimirov and Mosses proposed a rewrite system for deciding regular expressions equivalence of which Almeida et al. presented an improved variant. Hopcroft and Karp proposed an almost linear algorithm for testing the equivalence of two deterministic finite automata that avoids minimisation. In this paper we improve the best-case running time, present an extension of this algorithm to non-deterministic finite automata, and establish a relationship between this algorithm and the one proposed in Almeida et al. We also present some experimental comparative results. All these algorithms are closely related with the recent coalgebraic approach to automata proposed by Rutten