Automated Reasoning in Quantified Modal and Temporal Logics

Centre for Intelligent Systems and their ApplicationsThis thesis is about automated reasoning in quantified modal and temporal logics, with an application to formal methods. Quantified modal and temporal logics are extensions of classical first-order logic in which the notion of truth is extended to take into account its necessity or equivalently, in the temporal setting, its persistence through time. Due to their high complexity, these logics are less widely known and studied than their propositional counterparts. Moreover, little so far is known about their mechanisability and usefulness for formal methods. The relevant contributions of this thesis are threefold: firstly, we devise a sound and complete set of sequent calculi for quantified modal logics; secondly, we extend the approach to the quantified temporal logic of linear, discrete time and develop a framework for doing automated reasoning via Proof Planning in it; thirdly, we show a set of experimental results obtained by applying the framework to the problem of Feature Interactions in telecommunication systems. These results indicate that (a) the problem can be concisely and effectively modeled in the aforementioned logic, (b) proof planning actually captures common structures in the related proofs, and (c) the approach is viable also from the point of view of efficiency

From Discursive Practice to Logic? Remarks on Logical Expressivism

This paper proposes a novel account of the conditional locution as grounded in practices of goal- directed cooperative dialogue. It is argued that a conditional semantics can be obtained within a language fragment that lacks this locution, but supports assertive, inferential and directive prac- tices. We take Brandom’s logical expressivist programme as a point of departure, but argue that this programme is empirically flawed as it underestimates the pervasive context-dependence of linguistic items including logical vocabulary. We further take issue with his claim that a discursive practice involving only assertion and inference is sufficient for the conservative introduction and deployment of conditional vocabulary. A more promising route is provided by the introduction of directives, as in so-called “pseudo-imperatives” such as Get individuals to invest their time and the funding will follow: this has a conditional sense that if individuals invest their time, then funding will follow. We propose a semantic analysis for these forms which builds on Kukla and Lance’s account of prescriptives, and argue that our analysis more faithfully captures the “irrealis” nature of conditionals. The analysis is presented in terms of an information-state based dialogue model, with the information state comprising a partitioned commitment store. It is argued that our “dialogical” analysis of conditional reasoning is faithful to Brandom’s Sellarsian intuition of linguistic practice as a game of giving and asking for reasons. We conclude by contextualising and situating Brandom’s programme against the larger field of practice theory, by means of a comparison with the works of sociologist, anthropologist and philosopher Pierre Bourdieu, and suggest that this com- parison reveals further challenges to the expressivist programme. We also take note of Narasimhan et al’s recent proposals for agent-based modelling of social practice theory as a possible basis for future development

Ideology and culture: reflections on posthumanism, multiculturalism and Africa

This article introduces a structural model for ideology critique. The model is contextualised within the broader framework of a “discourse archaeology” and interpreted within the context of posthumanism which is compared with so-called postmodernism. Finally, the article explores the implications of the model for certain forms of multiculturalism, the concept of “Africa”, and Afrikaner protest politics

Creationism and evolution

In Tower of Babel, Robert Pennock wrote that “defenders of evolution would help their case immeasurably if they would reassure their audience that morality, purpose, and meaning are not lost by accepting the truth of evolution.” We first consider the thesis that the creationists’ movement exploits moral concerns to spread its ideas against the theory of evolution. We analyze their arguments and possible reasons why they are easily accepted. Creationists usually employ two contradictive strategies to expose the purported moral degradation that comes with accepting the theory of evolution. On the one hand they claim that evolutionary theory is immoral. On the other hand creationists think of evolutionary theory as amoral. Both objections come naturally in a monotheistic view. But we can find similar conclusions about the supposed moral aspects of evolution in non-religiously inspired discussions. Meanwhile, the creationism-evolution debate mainly focuses — understandably — on what constitutes good science. We consider the need for moral reassurance and analyze reassuring arguments from philosophers. Philosophers may stress that science does not prescribe and is therefore not immoral, but this reaction opens the door for the objection of amorality that evolution — as a naturalistic world view at least — supposedly endorses. We consider that the topic of morality and its relation to the acceptance of evolution may need more empirical research

Multimodal representation and the making of knowledge : a social semiotic excavation of learning sites

This research is concerned with the construction of knowledge as evidenced in the multimodal representations of students. In the spirit of an archaeological excavation it seeks to uncover evidence of that which can not be seen; of learning. It provides systematic classification and analysis of multimodal texts retrieved from secondary school science and history lessons. By conducting this analysis and accounting for the conditions of representation that stimulate learning it also demonstrates the instrumentality of representational activity in the making of knowledge.\ud Applying social semiotic theory to textual artefacts from the two sites, a new methodology is utilised to expose evidence of learning. This methodology is derived from theories of social semiotics (Halliday, 1978 and Hodge and Kress, 1988) and multimodality (Kress and van Leeuwen, 1996). It is based on a conception of learning as a process in which the status and identity of the individual are changed. It is informed by, amongst others, Bernstein (1996) - in relation to the socialising of individuals through systems of education and by Vygotsky (1962) - in relation to the shaping of consciousness.\ud The thesis consists of the description and demonstration of new methods for multimodal analysis of students' representational activity. The technique used for the presentation of data is tracking semiosis and for analysis process charting and mode mapping. Together these methods expose changes arising from the reconfigurations, transformations and transductions undertaken by students engaged in representational activity. In so doing, new directions are offered for the orientation of education practices in the face of rapidly changing patterns of communication. The efficacy of learning in multiple modes is also established and groundwork laid for fresh approaches to assessment. \u

Advanced photonic and electronic systems WILGA 2018

WILGA annual symposium on advanced photonic and electronic systems has been organized by young scientist for young scientists since two decades. It traditionally gathers around 400 young researchers and their tutors. Ph.D students and graduates present their recent achievements during well attended oral sessions. Wilga is a very good digest of Ph.D. works carried out at technical universities in electronics and photonics, as well as information sciences throughout Poland and some neighboring countries. Publishing patronage over Wilga keep Elektronika technical journal by SEP, IJET and Proceedings of SPIE. The latter world editorial series publishes annually more than 200 papers from Wilga. Wilga 2018 was the XLII edition of this meeting. The following topical tracks were distinguished: photonics, electronics, information technologies and system research. The article is a digest of some chosen works presented during Wilga 2018 symposium. WILGA 2017 works were published in Proc. SPIE vol.10445. WILGA 2018 works were published in Proc. SPIE vol.10808

Is seeking certainty in climate sensitivity measures counterproductive in the context of climate emergency? The case for scenario planning

Climate emergency is fast becoming the overriding problem of our times and rapid reductions in carbon emissions a primary policy focus that is liable to affect all aspects of society and economy. A key component in climate science is the “climate sensitivity” measure and there has been a recent attempt using Bayesian updating to narrow this measure in the interests of “firming up the science”. We explore a two-stage argument in this regard. First, despite good intentions, use of Bayes sits awkwardly with uncertainty in the form of known unknowns and surprise. Second, narrowing the range may have counterproductive consequences, since the problem is anthropogenic climate change, and there are asymmetric effects from under-response in the face of irreversible and ampliative effects. As such, narrowing the range using Bayes may inadvertently violate the precautionary principle. We take from this that there is a case to be made for scenario focused decision frameworks

Pathways to power: class, hyper-agency and the French corporate elite

publication-status: Acceptedtypes: ArticleAuthor's post-print draft. Definitive version published by Sage; available online at http://online.sagepub.com/This paper explores pathways to power from the perspective of the French corporate elite. It compares those who enter the ‘field of power’ with those who fail to reach this final tier. Adopting an innovative econometric approach, we develop and test three hypotheses. These underline the pivotal role of external networks and the strategic advantage of hyper-agency in maintaining power; and indicate that social origin remains a powerful driver in determining success. Birthright and meritocracy emerge as two competing institutional logics which influence life chances. Higher-status agents benefit from mutual recognition which enhances their likelihood of co-option to the extra-corporate networks that facilitate hyper-agency. The objectification of class-based differences conceals their arbitrary nature while institutionalizing the principles informing stratification. We re-connect class analysis with organizational theory; arguing that social origin exerts an enduring influence on selection dynamics which inform processes of hierarchical reproduction in the corporate elite and society-at-large

Is it still "cycling"? Pedelec-commuting from a social-practice-perspective

The sales of pedelecs are currently skyrocketing in Germany and in many other places. As a low-carbon means of mobility, pedelecs have the potential to make a substantial contribution to the mobility transition. This thesis employs practice theory as proposed by Shove et al. (2012) to investigate this quickly evolving phenomenon. The analysis is based on interviews with e-bike commuters which were investigated using template analysis and exploratory memos. To obtain a broad picture the practice, a maximum variance sampling strategy was carried out in two cities that vary substantially with regard to velomobility: Wuppertal and Münster. This thesis one hand presents the first encompassing account on the practice elements which commuting by pedelec is composed of. It hence contributes to the debate about the depiction of practices. Furthermore, the thesis finds that pedelec commuting should be conceptualized as a variant of velomobility and not as a variant of motoring or as an independent practice. Yet, the elements integrated in pedelec-commuting are found to clearly differ from those of cycling, so that pedelec-commuting meets the requirements of everyday life much better than commuting on non-electrified bikes. The findings of this thesis suggest several pathways to strengthening this novel practice. The capacity of e-biking to serve mundane trips can for example be supported through the normalization of the use of weather- and transport relevant materials and competences. Deeper linkages with interacting practices from other sectors, such as an integration of cycling materials (GPS-trackers) into policing practices, can also con-tribute to this goal. With regard to research, the present work offers starting points for quantifications, for example on the relative importance of single elements as well as on the characteristics of their relations among each other or with regard to typical constellations of elements

Patterns of recruitment, growth and mortality of the mussel, Mytilus Galloprovincialis in relation to wave exposure and tidal elevation

Population patterns of the alien mussel Mytilus galloprovincialis were investigated at two locations on the west coast of South Africa: Camps Bay and Groenrivier. Specifically, wave exposure and zonation were examined for their effect on mussel cover and total density, mussel size and recruit intensity. Two areas were compared at Camps Bay; the first was a prominent rock experiencing heavy wave action, and the second was a sheltered bay. Three areas were selected at Groenrivier, the third experiencing an intermediate gradient of wave action. A number of interesting patterns emerged, although not all were statistically significant. At both Camps Bay and Groenrivier mussel cover increased with increasing wave exposure and decreased with increasing tidal height. The exception to this zonational trend was exhibited in the very sheltered bay at Groenrivier, where mussel cover increased upshore, from 2% to 6%. Total mussel density and recruit intensity declined with a reduction in wave action at both locations. An unexpected zonational pattern occurred at both Camps Bay and Groenrivier - total densities tended to be greater upshore, a pattern which closely followed recruit densities. The maximum size achieved by mussels is greatest at more exposed areas, but the difference between sheltered and exposed regions at Camps Bay was not notable. Maximum shell size tended to decrease with increasing tidal height in all areas but the sheltered bay at Groenrivier, where little variation in maximum size occurred. Multivariate comparisons of population demography between all of the sites revealed that the sheltered site at Camps Bay was most similar to the semi-exposed site at Groenrivier, which points to similar environmental conditions in these areas. This pattern was repeated for total densities, a result which supports the previous suggestion. The sheltered bay at Groenrivier was most dissimilar in both demographic structure and density to all other sites. Bibliography: leave 89-99