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The Aamodt and Kjus problem
Get PDFWe conjecture that an interesting special case of the known NP-complete problem, Multiprocessor Scheduling (MPS), is well inside P. We present a number of results that supports the conjecture. We also give some empirical results that strengthen our beliefs concerning the conjecture
Towards a Multi Metamodelling Approach for Developing Distributed Healthcare Applications
Get PDFModel Driven Engineering (MDE) uses formal methods to build mathematically rigorous models of complex systems. Metamodelling plays an important role in MDE as it is used to specify domain specific modelling languages. However, the potential of metamodelling has not been fully explored. Current approaches of MDE are often at a low level of abstraction and lack domain concepts for specifying behavior. In previous work, we proposed a multi metamodelling approach that captures the complexity of systems by using a metamodelling hierarchy, built from individually defined metamodels, each capturing different aspects of a healthcare domain. In this paper, we focus on modelling distributed healthcare applications and present an example from the healthcare domain. We address certain modelling aspects related to distributed applications such as process modelling, using message passing communication, and coordination of processes and resources
A full parallel Quicksort algorithm for multicore processors
Get PDFThe problem addressed in this paper is that we want to sort an integer array a[] of length n in parallel on a multi core machine with p cores using Quicksort. Amdahl’s law tells us that the inherent sequential part of any algorithm will in the end dominate and limit the speedup we get from parallelisation. This paper introduces ParaQuick, a full parallel quicksort algorithm for use on an ordinary shared memory multi core machine that has just a few simple statements in its sequential part. It can be seen as an improvement over traditional parallelization of the Quicksort algorithm, where one follows the sequential algorithm and substitute recursive calls with the creation of parallel threads for these calls in the top of the recursion tree. The ParaQuick algorithm, starts with k parallel threads, where k is a multiple of p (here k = 8*p) in a k way partition of the original array with the same pivot value, and hence we get 2k partitioned areas in the first pass. We then calculate where the pivot index, the division between the small and large elements if this had been ordinary sequential Quicksort partition. In full parallel we then swap all small elements to the right of this pivot index with the large elements to the left of this pivot index – these two ‘displaced’ sets are by definition of equal size. We can then recursively with half of the threads now do the left part, and with the other half of the threads the right part (more details and synchronization considerations in the paper). Finally, when there is only one thread left working on one such area, sequential Quicksort and Insertionsort are used, as in the traditional way of doing parallel Quicksort. In the last part of the paper, this new algorithm is empirically tested against two other algorithms and Arrays.sort from the Java library. Five different distributions of the numbers to be sorted end three different machines with p = 2(4 hyper threaded), 4(8) and 32(64) are tested. Finally, conclusions are presented and an explanation is given why this ParaQuick algorithm for large values of n and some distributions is so much faster than a traditional parallelisation
The anti-democratic employment of school cyberspace. A pilgrimage into an Arab winter?
Get PDFIn this article I wish to bring critical attention to the manner in which the Internet and intranet are employed as pedagogical space in schools. Within this article I also articulate my struggle to understand and conduct research in this place of electronic communication. Informed by Nietzsche and some biblical scripture, I suggest that what we are finding in education is a church of the intranet that is worshiped as a shelter of safety for educational learning. However, my contention is that a lack of control of uploaded and downloaded digital media results in spaces which mirror extant societal prejudices and bigotry. To evidence my argument I present specific data from English schools' colonisation of cyberspace and suggest that in this terra nullius1 a new civilisation, constructed upon old world ideals, ‘conformed’ the construction of the disabled indigene
Simulation games as educational texts and mediational tools for intercultural learning
Get PDFThis article reports on the results of research carried out with university students using simulation games as educational resources. The aim of the study was to analyse the role of simulation games as mediational tools in the creation of playful, creativity-based educational interaction and the development of intercultural competence. Our approach is grounded in Moeglin’s (2008) discussion of the role of mediatisation in the process of learning, Huizinga’s (1971) theory of play (as it relates to learning), and Vygotsky’s (1978) idea of a social constructivist pedagogy. The results suggest that simulation games exhibit the potential to develop important elements of intercultural competence, by helping to: turn learning into play, develop decision-making and other intercultural skills (as opposed to simply providing knowledge), and maximise students’ potential learning outcomes. In addition, simulation games provide a multimodal platform, encouraging the development of students’ ability to create, read and interpret multimodal texts. It is proposed that simulation games can perform an important role as auxiliary tools to be used alongside traditional modes of education
Achieving Accessible Rich Internet Applications
Get PDFThis work presents guidelines on making accessible Rich Internet Applications (RIAs). The guidelines have been developed based on a thorough literature review, summarizing the current accessibility issues related to RIA. Existing solutions and recommendations have been processed and converted into a set of guidelines, aimed at those responsible for developing RIA solutions. Participants working with web development and accessibility evaluated the guidelines. The most important contribution from this project to the field of web accessibility research is strong indications of a need for process oriented accessibility guidelines
Matematikk er eit pratefag og andre røynsler frå eit omvendt klasserom
Get PDFI emnet Diskret Matematikk har me brukt omvendt klasserom sidan hausten 2013. Førelesingane er tilgjengeleg som videoopptak på ei vevside. medan klasseromstida vert brukt til tovegskommunikasjon og aktiv læring i ein eller annan form. Det kan innebera spørsmål frå studentane, vegleiing, gruppearbeid, diskusjon rundt oppgåver, med meir. Sjølv om me har sett mange positive verknader av dette opplegget, skal ein merkja seg at omvendt klasserom ikkje er noka sølvkule. Den aktive læringa kan leggjast opp på mange ulike måtar, og ikkje alle fungerer like bra. Det har teke to år å nærma seg ein tilfredsstillande form, og me er enno ikkje heilt i mål. Desse røynslene og løysingane skal me utdjupa i artikkelen
Economic Markets for Video Streaming Services: A Case Study of Netflix and Popcorn Time
Get PDFVideo streaming services are considered as the new standard method of delivering entertainment to the public. Netflix, one of the leading providers of video streaming, has reported that piracy continues to be their biggest competitor, referring to Popcorn Time specifically. Popcorn Time uses illegal means of providing video streaming. Popcorn Time offers a similar or even better video streaming experience compared to Netflix. In this paper, we study the competition between legal and illegal video streaming services. In particular, this paper elaborates on the analysis of network effects in relation to video streaming services and explains how an individual who uses video streaming can affect the overall value of the network where a particular video is being streamed. We propose the Competitive Video Streaming Model (CVSM), based on the Bass Diffusion model. The CVSM is applied to model the competition between Netflix and Popcorn Time. The main findings show that the timing of the onset of network effects is significant for the temporal evolution of adopters. Our results also suggest that the competitiveness of video streaming services depends on how the service provider is distributing the video streaming contents. It shows that distributing video streaming contents through P2P network subsidizes the growth of adopters to a greater extent compared to a client-server network. As such, the results of this study support the hypothesis that network effects can strengthen the competitiveness of illegal video streaming services
Interactive modelling and simulation using blending techniques
Get PDFBlending splines are constructions where local geometry is blended together by a blending function to create global geometry. The different basis functions has different properties, which can be suited for different problems. Different basis functions, properties and the implementation of physical properties with a focus towards utilizing parts of blending splines in an isogeometric analysis (IGA) context constitutes the basis for the current study. This paper gives an introduction to a newly started PhD project regarding the use of blending splines in modeling and simulation environments
The authenticity of resources for the teaching of foreign languages and cultures in France: variable geometry notion
Get PDFIn France, in the 1970s, a new methodology for the teaching of foreign languages and cultures emerged called “communicative”, generating an evolution of textbooks and classroom practices. The notion of the authentic document, from a Frenchperspective, asserted itself during this time as pivotal in these developments. It would, thereafter, play an important role in the discourse of didacticians and practitioners.An examination of the history of the notion of authentic document for the teaching/learning of foreign languages and cultures leads to the finding of a redefinition of practitioners' and students' activities, hinged on these evolving methodologies. Whatis more, discussions around the notion of authenticity invite the consideration of parallels with concepts whose uses extend to the educational sciences, namely those of artifact and instrument