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Interactions between climate change, competition, dispersal, and disturbances in a tree migration model

Potentially significant shifts in the geographical patterns of vegetation are an expected result of climate change. However, the importance of local processes (e.g., dispersal, competition, or disturbance) has been often ignored in climate change modeling. We develop an individual-based simulation approach to assess how these mechanisms affect migration rate. We simulate the northward progression

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Biodiversity conservation requires an understanding of the extent to which a landscape can contribute to species life-cycle. Conceived as a dynamic mosaic of spatial units with different properties, landscape is a very relevant scale for dealing with biodiversity issues. This paper aims at analysing the relationships and overlapping between this geography and landscape ecology as two scientific fi

Landscape patterns and agriculture : Modelling the long-term effects of human practices on Pinus sylvestris spatial dynamics (Causse Mejean, France)

This paper focuses on understanding human impact on landscape. Both ecological and human practices are analysed as interacting processes. An agent-based model integrating biological and historical knowledge is used to analyse the pattern of Scots Pine encroachment in a French Mediterranean upland. In the STIPA model, pine trees are autonomous agents and a cellular automaton simulates land-use. We

Delay spread properties in a measured massive MIMO system at 2.6 GHz

Massive multiple-input multiple-output (MIMO) systems, where the base station (BS) is equipped with a large number of antennas and the mobile devices have a single antenna, can significantly enhance the system performance. In many wireless systems inter symbol interference (ISI) due to delay dispersion of the channel can dramatically affect the demodulation process of the received signals. Precodi

Vibrations in a Built Environment : Prediction and Reduction

Vibrations in a built environment can exceed the requirements for sensitive equipment in a building or can cause annoyance to residents. Hence, there is often a need for reducing such vibrations. The vibrations can originate from ambient sources such as motorway traffic, or from internal sources such as people walking inside the building. Disturbing vibrations can be reduced by reduction measures.

Roller coaster loop shapes revisited

In 'Rollercoaster loop shapes', (Pendrill 2005 Phys. Educ. 40 517) the author started from the observation that although textbook loops are often circular, real rollercoaster loops are not. In this paper the mathematical description of various possible loop shapes, as well as their riding properties was discussed and also how a study of loop shapes can be used in physics education.

Sweden. Legal Philosophy in the 20th Century

The evolution of legal philosophy in Sweden in the first half of the 20th century basically coincides with the history of the so-called Uppsala School, which will be treated extensively in Tome 2 of this volume, in the part devoted to legal realism. Here I will be dealing with Swedish legal philosophy after that period, from the early 1940s onward, when the hitherto dominant influence of the philo

Anders Vilhelm Lundstedt: In Quest of Reality

More often than not, it is asserted that Anders Vilhelm Lundstedt (1882-1955), a disciple and friend of Axel Hägerström who enthusiastically embraced the latter’s philosophical theories, (i) went to great lengths to apply those theories in the central fields of law but (ii) actually deviated from Hägerström’s teachings by introducing the complex notion of "social welfare" (or "social utility") as

Bo i Ro : Texter från ett tvärvetenskapligt symposium om boende, buller och hälsa. Läkaresällskapets hus i Stockholm, den 20 oktober 2016

Sveriges Regering fattade den 9 april 2015 beslut om en ny förordning medbestämmelser om riktvärden för buller utomhus för spårtrafik, vägar ochflygplatser vid bostadsbyggnader. Förordningen (2015:216) om trafikbullervid bostadsbyggnader träder i kraft den 1 juni 2015. I denna förordning finnsförändrade riktvärden för bullerexponering vid bostader som tillåter betydligtmer buller än tidigare, någo

Palladium seeded GaAs nanowires

In this work, we present a detailed investigation of the growth of palladium-seeded GaAs nanowires. Nanowires grown on GaAs (111)B substrates consist of three different morphologies, denoted as curly (containing multiple kinks), inclined (relative to the substrate, such as 〈001〉), and vertical. We show that the relative yield of the different types is controllable by a combination of V/III ratio a