| 1. |
- Mamontov, Eugen, 1955
(författare)
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Ordinary differential equation system for population of individuals and the corresponding probabilistic model
- 2008
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Ingår i: Mathl. Computer Modelling. - : Elsevier BV. - 0895-7177.
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Tidskriftsartikel (refereegranskat)abstract
- The key model for particle populations in statistical mechanics is the Bogolyubov–Born– Green–Kirkwood–Yvon (BBGKY) equation chain. It is derived mainly from the Hamilton ordinary differential equation (ODE) system for the vectors of the particle states in the particle position-momentum phase space. Many problems beyond physics or chemistry, for instance, in the living-matter sciences (biology, medicine, ecology, and scoiology) make it necessary to extend the notion of a particle to an individual, or active particle. This challenge is met by the generalized kinetic theory. It implements the extension by extending the phase space from the space of the position-momentum vectors to more rich spaces formed by the state vectors with the entries which need not be limited to the entries of the position and momentum: they include other scalar variables (e.g., those associated with modelling homeorhesis or other features inherent to the individuals). One can assume that the dynamics of the state vector in the extended space, i.e. the states of the individuals (rather than common particles) is also described by an ODE system. The latter, however, need not be the Hamilton one. The question is how one can derive the analogue of the BBGKY paradigm for the new settings. The present work proposes an answer to this question. It applies a very limited number of carefully selected tools of probability theory and common statistical mechanics. It in particular uses the well-known feature that the maximum number of the individuals which can mutually interact simultaneously is bounded by a fixed value of a few units. The present approach results in the finite system of equations for the reduced many-individual distribution functions thereby eliminating the so-called closure problem inevitable in the BBGKY theory. The thermodynamic-limit assumption is not needed either. The system includes consistently derived terms of all of the basic types known in kinetic theory, in particular, both the “mean-field” and scattering-integral terms, and admits the kinetic equation of the form allowing a direct chemical-reaction reading. The present approach can deal with Hamilton’s equation systems which are nonmonogenic and not treated in statistical mechanics. The proposed modelling suggests the basis of the generalized kinetic theory and may serve as the stochastic mechanics of population of individuals.
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| 2. |
- Munthe, Christian, 1962
(författare)
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Mellan genialitet och galenskap: Recension av Benjamin Labatuts roman "MANIAC"
- 2023
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Ingår i: Tidskriften Alba. - 1403-5448.
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Recension (övrigt vetenskapligt/konstnärligt)abstract
- John von Neumann var ett för de allra flesta okänt ungerskt underbarn av judisk härkomst som sedermera flydde undan nazisterna till USA, där han dog 1957. Han var ett matematiskt universalgeni som gav viktiga, för att inte säga avgörande, bidrag till fysikens, biologins, data- och samhällsvetenskapens och meteorologins (och därmed klimatvetenskapens) utveckling under 1900-talet. Vid sidan av den mer allmänt kände Alan Turing föranstaltade han det som vi idag lär känna som A.I. och teoretiserade tidigt om hur man kunde tänka på maskiner som livsformer analogt med biologiska – en idé som idag ingår både i evolutionsbiologiska verktygslådor liksom i visioner och mardrömsscenarier om en teknologisk singularitet bortom vilken generella A.I. dominerar och, i värsta fall, tränger ut människoarten. Det är denne märkliga och skrämmande person Benjamín Labatuts välskrivna roman sätter i centrum för en berättelse om gränslandet mellan genialitet och galenskap, vetenskap och teknik från förra sekelskiftet till nu, logikseminariernas tankelekar och konkret global politisk utveckling på liv och död. Romanen är pärlande klart översatt av Anna Petronella Foultier. Man behöver nog ha ett visst intresse för vetenskap, teknik och/eller global politik för att uppskatta den fullt ut, men mycket sådant förklaras under hand på ett skenbart enkelt vis, så jättestora kunskaper behövs inte.
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| 3. |
- Durkin, Louisa, et al.
(författare)
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When mycologists describe new species, not all relevant information is provided (clearly enough).
- 2020
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Ingår i: MycoKeys. - 1314-4049. ; 72, s. 109-128
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Tidskriftsartikel (refereegranskat)abstract
- Taxonomic mycology struggles with what seems to be a perpetual shortage of resources. Logically, fungal taxonomists should therefore leverage every opportunity to highlight and visualize the importance of taxonomic work, the usefulness of taxonomic data far beyond taxonomy, and the integrative and collaborative nature of modern taxonomy at large. Is mycology really doing that, though? In this study, we went through ten years' worth (2009-2018) of species descriptions of extant fungal taxa - 1,097 studies describing at most ten new species - in five major mycological journals plus one plant journal. We estimated the frequency at which a range of key words, illustrations, and concepts related to ecology, geography, taxonomy, molecular data, and data availability were provided with the descriptions. We also considered a range of science-demographical aspects such as gender bias and the rejuvenation of taxonomy and taxonomists as well as public availability of the results. Our results show that the target audience of fungal species descriptions appears to be other fungal taxonomists, because many aspects of the new species were presented only implicitly, if at all. Although many of the parameters we estimated show a gradual, and in some cases marked, change for the better over time, they still paint a somewhat bleak picture of mycological taxonomy as a male-dominated field where the wants and needs of an extended target audience are often not understood or even considered. This study hopes to leave a mark on the way fungal species are described by putting the focus on ways in which fungal taxonomy can better anticipate the end users of species descriptions - be they mycologists, other researchers, the public at large, or even algorithms. In the end, fungal taxonomy, too, is likely to benefit from such measures.
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| 4. |
- Petersson, Jesper, 1974, et al.
(författare)
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Off the record: The invisibility work of doctors in a patient-accessible electronic health record information service.
- 2021
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Ingår i: Sociology of health & illness. - : Wiley. - 1467-9566 .- 0141-9889. ; 43:5, s. 1270-1285
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Tidskriftsartikel (refereegranskat)abstract
- In this article, we draw on Michael Lipsky's work on street-level bureaucrats and discretion to analyse a real case setting comprising an interview study of 30 Swedish doctors regarding their experiences of changes in clinical work following patients being given access to medical records information online. We introduce the notion of invisibility work to capture how doctors exercise discretion to preserve the invisibility of their work, in contrast to the well-established notion of invisible work, which denotes work made invisible by parties other than those performing it. We discuss three main forms of invisibility work in relation to records: omitting information, cryptic writing and parallel note writing. We argue that invisibility work is a way for doctors to resolve professional tensions arising from the political decision to provide patients with online access to record information. Although invisibility work is understood by doctors as a solution to government-initiated visibility, we highlight how it can create difficulties for doctors concerning accountability towards patients, peers and authorities.
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| 5. |
- Petersson, Jesper, 1974
(författare)
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Blurring the shoreline: De- and re-infrastructuring and the changing colors of European flood policy
- 2021
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Ingår i: Environment and Planning E: Nature and Space. - : SAGE Publications. - 2514-8494 .- 2514-8494 .- 2514-8486. ; 4:2, s. 623-644
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Tidskriftsartikel (refereegranskat)abstract
- This paper provides a genealogy of the emergence of a common EU flood policy, including the scope and direction of this policy. Noticing how EU policy proposes green infrastructure (associated with using nature as a buffer zone in managing floods) as an alternative to grey infrastructure (implying fixed installations of concrete and cement), this paper adopts the theoretical lens of the so-called infrastructural turn, which advocates a relational investigation of infrastructure. By engaging this approach, the paper shows how flood infrastructure can contain very different compositions of (unruly) water and (settled) land. A narrative of a historically strong focus on guarding society from the powerful forces of nature through a fixed line of defense is increasingly giving way to more muddy states—quite literally—where society is expected to learn to live with flooding and show ecological consideration. To capture the EU’s, and especially the European Commission’s efforts to establish a pan-European flood infrastructure that accommodates this turn, the concepts of de- and re-infrastructuring are developed. These concepts act as heuristic devices to capture how policy performs some combinations between water and land as constituting an attractive and functional flood infrastructure, but constitutes other infrastructural relations of the aquatic and the terrestrial as undesirable and, hence, as malfunctioning. This performative act of distinguishing between what constitutes “good and proper” versus “bad and undesirable” infrastructure is referred to as a politics of infrastructure.
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| 6. |
- Vitalis Pemunta, Ngambouk, 1973, et al.
(författare)
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Modern State Law: Regulating Tradition or Protecting the Environment in the Mankon Kingdom of Northwest Cameroon?
- 2019
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Ingår i: Endemic Species. Eusebio Cano Carmona (red.). - London, United Kingdom : Intechopen. - 9781839623547
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Bokkapitel (refereegranskat)abstract
- Most African countries including Cameroon find themselves in a situation of legal pluralism and at crossroads with implications for the sustainable management of natural resources. Traditional institutions and knowledge systems have been hailed as invaluable mechanisms for the conservation of flora and fauna. This chapter examines the conflict between traditional institutions and State law in the hierarchically stratified Mankon Kingdom of the Grassfield region of Northwest Cameroon where the latter prohibits the harvesting of culturally valuable plant and animal species for myriad ritual ceremonies and for therapeutic purposes. It demonstrates that the lack of cultural sensitivity can be antithetical to conservation initiatives. In other words, there is the need to align current legislative regulations for the management of natural species with the traditional use of territory, gender roles as well as to raise the cultural and educational level of the population through sensitization on the need to conserve the natural environment on which their culture depends for its survival.
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| 7. |
- Mamontov, Eugen, 1955, et al.
(författare)
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Managing panic-stricken crowds: The need in quantitative models for social dynamics
- 2007
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Ingår i: Abstract Booklet, The 8th Annual Conference of the European Sociological Association.
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Konferensbidrag (refereegranskat)abstract
- Panics typically occur during disaster or social crisis. Panics in crowds in public sites (airports, hospitals, supermarkets, office buildings, air- or sea-liners, trains, stadiums, downtown areas, etc.) often cause stampedes leading to injuries or deaths. How can we best organize public events at existing sites in order to prevent the tragic outcomes? How can one design new public sites to avoid the consequences of panic? What methods and tools can be applied? These questions determine the focus of the present work. Obviously, experimental approaches are inapplicable. Intuitive problem solving does not assure specific and consistent solutions. Therefore, the work concentrates on the non-intuitive, model-based approaches. Evaluation of the model-based solutions involves quantitative characteristics, e.g., the time of the evacuation, the probability for individuals to get injured, the concentration of oxygen, etc. Subsequently, any suitable model must be quantitative. Moreover, the behaviour of crowds develops continuously in both space and time. Thus, the models must also be space-time continuous. The work analyzes these and other features of the models for social dynamics and emphasizes the key differences from the dynamical models in the natural sciences studying nonliving matter. The related application aspects and directions for future research are also discussed.
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| 8. |
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| 9. |
- Jansson, Fredrik
(författare)
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What games support the evolution of an ingroup bias?
- 2015
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Ingår i: Journal of Theoretical Biology. - : Elsevier BV. - 0022-5193 .- 1095-8541. ; 373, s. 100-110
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Tidskriftsartikel (refereegranskat)abstract
- There is an increasing wealth of models trying to explain the evolution of group discrimination and an ingroup bias. This paper sets out to systematically investigate the most fundamental assumption in these models: in what kind of situations do the interactions take place? What strategic structures - games - support the evolution of an ingroup bias? More specifically, the aim here is to find the prerequisites for when a bias also with respect to minimal groups - arbitrarily defined groups void of group-specific qualities - is selected for, and which cannot be ascribed to kin selection.Through analyses and simulations of minimal models of two-person games, this paper indicates that only some games are conducive to the evolution of ingroup favouritism. In particular, this class does not contain the prisoners׳ dilemma, but it does contain anti-co-ordination and co-ordination games. Contrasting to the prisoners׳ dilemma, these are games where it is not a matter of whether to behave altruistically, but rather one of predicting what the other person will be doing, and where I would benefit from you knowing my intentions.In anti-co-ordination games, on average, not only will agents discriminate between groups, but also in such a way that their choices maximise the sum of the available payoffs towards the ingroup more often than towards the outgroup. And in co-ordination games, even if agents do manage to co-ordinate with the whole population, they are more likely to co-ordinate on the socially optimal equilibrium within their group. Simulations show that this occurs most often in games where there is a component of risk-taking, and thus trust, involved. A typical such game is the stag hunt or assurance game.
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| 10. |
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