On the cost-complexity of multi-context systems

Multi-context systems provide a powerful framework for modelling information-aggregation systems featuring heterogeneous reasoning components. Their execution can, however, incur non-negligible cost. Here, we focus on cost-complexity of such systems. To that end, we introduce cost-aware multi-context systems, an extension of non-monotonic multi-context systems framework taking into account costs incurred by execution of semantic operators of the individual contexts. We formulate the notion of cost-complexity for consistency and reasoning problems in MCSs. Subsequently, we provide a series of results related to gradually more and more constrained classes of MCSs and finally introduce an incremental cost-reducing algorithm solving the reasoning problem for definite MCSs

70 Years Since the Liberation of the Netherlands From Memory to Remembrance

On 16 October 2014, the Canadian War Museum partnered with the Embassy of the Kingdom of the Netherlands to host the first in the Embassy’s national series of lectures “From Memory to Remembrance” in the Museum’s Barney Danson Theatre. The Embassy launched the series in the fall of 2014, with subsequent events in February and April 2015, with Canadian and Dutch scholars helping the audience to follow the Canadian military campaign from the Battle of the Scheldt to the German capitulation at Wageningen on 5 May 1945. Attended by His Excellency Governor General David Johnston, the Ottawa event featured Terry Copp, Wilfrid Laurier University, who lectured on how the Canadians’ major engagements in the Scheldt Battle unfolded, and Ben Schoenmaker of the University of Leiden and Netherlands Institute of Military History, who spoke to the Dutch perspective of the 1944-1945 battles and views of the liberating forces. Dean Oliver, Director of Research at the Canadian Museum of History moderated. On 26 February 2015, the University of Calgary hosted the second instalment of the series, moderated by David Bercuson and featuring Canadian historian Mark Zuehlke and Erwin van Loo, Senior Research Fellow at the Dutch Institute for Military History. The final instalment in the series took place in Fredericton on 1 April 2015, in partnership with the Gregg Centre for the Study of War and Society, and featured the Centre’s Deputy Director, Lee Windsor, and Lieutenant-Colonel Wouter Hagemeijer, Assistant Professor at the Netherlands Defence Academy. The event was moderated by Marc Milner, the Gregg Centre’s director. His Excellency Cees Kole, Ambassador of the Netherlands to Canada, opened the first event in the series Ambassador Kole joined the Netherlands’ Ministry of Foreign Affairs in 1984. Before his posting to Ottawa in 2013, he served in diplomatic postings in Warsaw, Brussels, Paris, and as ambassador to Iran. The ambassador’s speech opening the From Memory to Remembrance series offers some interesting insights into the interplay between lived experiences, history, and remembrance, as well as highlighting the many connections between Canada and the Netherlands, which the presenters in the series further underlined. The speech is reproduced in full below

Multiple representations in web-based learning of chemistry concepts

A new chemistry curriculum for secondary schools is currently under construction in the Netherlands, in which chemical knowledge will be embedded in contexts that show applications of chemistry in the society. Several research groups develop such modules and a committee appointed by the Dutch Ministry of Education advises about the chemical content and concepts.\ud A central issue in chemistry education is the relation between the real, molecular and symbolic world. Skilled chemists switch easily between these worlds, but beginning students do not. They could get better results and will be more able to solve problems if they would make better connections between the three chemical worlds. The University of Twente has developed a series of lessons about the particle model. Included in this instruction material are animations of chemical processes at the molecular level. In the lessons students are supported and stimulated to make connections between the three chemical worlds. Students are shown the importance of new chemical knowledge in society. The mental images and the knowledge schemata of the students are investigated in this research. The students were interviewed before they received instruction, and after they received about half of the instruction. At the end of the instruction they were asked to make a concept map.\ud It appeared that the links between the real, molecular and symbolic world are not strengthened after the instruction. The students make more links between the real and symbolic world, but hardly connect these world to the molecular world or vice versa. There is still a gap between the students’ mental models and scientifically accepted models as represented in animations and illustrations in the instruction. Most students liked the animations in the instruction and mentioned them as strong point. It is therefore surprising that some students could not remember the animations when they were interviewed, whilst others their representations were about the same as the animations. Clearly, the effectiveness of the animations must be enhanced and more research is needed for this