Agent-Based Simulation for Infectious Disease Modelling over a Period of Multiple Days, with Application to an Airport Scenario

With the COVID-19 pandemic, the role of infectious disease spreading in public places has been brought into focus more than ever. Places that are of particular interest regarding the spread of infectious diseases are international airport terminals, not only for the protection of staff and ground crew members but also to help minimize the risk of the spread of infectious entities such as COVID-19 around the globe. Computational modelling and simulation can help in understanding and predicting the spreading of infectious diseases in any such scenario. In this paper, we propose a model, which combines a simulation of high geometric detail regarding virus spreading with an account of the temporal progress of infection dynamics. We, thus, introduce an agent-based social force model for tracking the spread of infectious diseases by modelling aerosol traces and concentration of virus load in the air. We complement this agent-based model to have consistency over a period of several days. We then apply this model to investigate simulations in a realistic airport setting with multiple virus variants of varying contagiousness. According to our experiments, a virus variant has to be at least twelve times more contagious than the respective control to result in a level of infection of more than 30%. Combinations of agent-based models with temporal components can be valuable tools in an attempt to assess the risk of infection attributable to a particular virus and its variants

Agent-based simulation of pedestrian dynamics for exposure time estimation in epidemic risk assessment

Purpose With the coronavirus disease 2019 (COVID-19) pandemic spreading across the world, protective measures for containing the virus are essential, especially as long as no vaccine or effective treatment is available. One important measure is the so-called physical distancing or social distancing. Methods In this paper, we propose an agent-based numerical simulation of pedestrian dynamics in order to assess the behavior of pedestrians in public places in the context of contact transmission of infectious diseases like COVID-19, and to gather insights about exposure times and the overall effectiveness of distancing measures. Results To abide by the minimum distance of 1.5 m stipulated by the German government at an infection rate of 2%, our simulation results suggest that a density of one person per 16m2 or below is sufficient. Conclusions The results of this study give insight into how physical distancing as a protective measure can be carried out more efficiently to help reduce the spread of COVID-19

Stativeness and Directionality in System and Text

The article aims at exploring the essence of the distinction between the two fundamental forms of language which the Danish linguist Louis Hjelmslev designated as system and text. After discussing and rejecting Hjelmslev's own characterizations of this distinction as that between either- or- and both-and-relations as well as several distinctions used by Roman Jakobson to characterize that distinction, the article proposes to consider the possibility to regard as the defining characteristic of the system stativeness and as that of the text directionality. On closer inspection, however, it turns out that these characteristics are only the dominant ones of the two forms of language, the system also displaying phenomena of directionality and the text phenomena of stativeness. These, however, play, within the respective forms of language, only a subordinate role. Subordinate directionality in the system is to be seen in the internal structure of all complex system-units, such as words as parts of the lexicon, and even between some of these units, namely numerals, themselves. Subordinate stativeness in the text, on the other hand, is displayed by enumerative coordinations, the concept of coordination comprising not only the coordinations of traditional grammar, but also a certain higher-level type of coordination, a type which I call macro-coordination

Sprachliche Propositionalitätstests

Der Begriff der Proposition hat in den letzten fünfundzwanzig Jahren weite Verbreitung gefunden und nimmt heute eine zentrale Stelle im Begriffsgebäude der Sprechakttheorie und vieler anderer Teildisziplinen der Linguistik ein. Zumeist wird er in der betreffenden Literatur einfach als bekannt vorausgesetzt; nur selten unterzieht man sich der Mühe eines Definitionsversuches. Dabei gibt es für ihn sehr viele unterschiedliche Bestimmungen. Daraus resultieren vielfach widersprüchliche Aussagen.Für die Linguistik ist deswegen ein sprachlicher Propositionalitätstest oder eine Gruppe solcher Tests ein Desiderat. Solche Tests sollen eine Möglichkeit liefern, auf der Basis sprachlicher Gegebenheiten zu entscheiden, was eine Proposition ist oder zur Proposition gehört, was nicht. Das Resultat soll - aufgrund der sprachlichen Kompetenz der Testbenutzer - intersubjektiv überprüft werden können, und so soll es möglich sein, über das bloße Behaupten der Propositionshaftigkeit eines sprachlichen Phänomens hinauszugelangen