1,691 research outputs found
High-resolution palynology reveals the land-use history of a Sami renvall in northern Sweden
Acknowledgements: This research was funded by the Leverhulme Trust through the Footprints on the Edge of Thule project, and was written under the auspices of the ERC-funded project Arctic Domus. Thanks are offered to Audrey Innes for laboratory assistance; Ian Foster for 210Pb dating; Gordon Cook for AMS radiocarbon analyses; and Martin Konert and the late Sjoerd Bohncke for assistance with LOI and related analyses. The comments of Tim Mighall, Jeff Blackford, Mari Kuoppamaa, two anonymous referees and the editor helped to improve the paper.Peer reviewedPublisher PD
A Holder Continuous Nowhere Improvable Function with Derivative Singular Distribution
We present a class of functions in which is variant
of the Knopp class of nowhere differentiable functions. We derive estimates
which establish \mathcal{K} \sub C^{0,\al}(\R) for 0<\al<1 but no is pointwise anywhere improvable to C^{0,\be} for any \be>\al.
In particular, all 's are nowhere differentiable with derivatives singular
distributions. furnishes explicit realizations of the functional
analytic result of Berezhnoi.
Recently, the author and simulteously others laid the foundations of
Vector-Valued Calculus of Variations in (Katzourakis), of
-Extremal Quasiconformal maps (Capogna and Raich, Katzourakis) and of
Optimal Lipschitz Extensions of maps (Sheffield and Smart). The "Euler-Lagrange
PDE" of Calculus of Variations in is the nonlinear nondivergence
form Aronsson PDE with as special case the -Laplacian.
Using , we construct singular solutions for these PDEs. In the
scalar case, we partially answered the open regularity problem of
Viscosity Solutions to Aronsson's PDE (Katzourakis). In the vector case, the
solutions can not be rigorously interpreted by existing PDE theories and
justify our new theory of Contact solutions for fully nonlinear systems
(Katzourakis). Validity of arguments of our new theory and failure of classical
approaches both rely on the properties of .Comment: 5 figures, accepted to SeMA Journal (2012), to appea
Effective communications on invasive alien species: Identifying communication needs of Swedish domestic garden owners
Invasive alien species threaten biodiversity with domestic gardens acting as a major pathway for the introduction of alien species. Even though the Nordic region is not currently a hotspot for biological invasions, the number of invasions in the Nordic area has been predicted to increase due to climate change. Given a time lag between introduction and invasion, many non-invasive horticultural alien species already introduced into gardens may become invasive in the future. This study aimed to identify the communication needs of Swedish garden owners regarding their management of invasive alien species. A survey among domestic garden owners, informed by topic specialists and local area experts, and interviews with garden owners were conducted in three different bio-climatic areas in a latitudinal gradient across Sweden. The questions targeted invasive alien species and their relations to biodiversity loss and climate change, as well as measures taken to control these species. Analysing the survey data collected in relation to measures taken to control invasive species, Bayesian Additive Regression Tree (BART) modelling was used to identify geographically varying communication needs of the domestic garden owners. In all study areas, the garden owners' measures taken to control invasive alien species were correlated with their strength of beliefs in having experienced local biodiversity loss. A majority of the garden owners were, moreover, uncertain about the impact of climate change on the invasiveness of alien species. In addition, the garden owners' capacity for identifying invasive alien species was often in need of improvement, in particular with respect to the species Impatiens glandulifera, Reynoutria japonica and Rosa rugosa. The results suggest that the evidence-based guidelines for effective communications we developed, have the potential to help communicators meet the local communication needs of garden owners across Sweden, in relation to the management of invasive alien garden species
A Maturity Assessment Framework for Conversational AI Development Platforms
Conversational Artificial Intelligence (AI) systems have recently
sky-rocketed in popularity and are now used in many applications, from car
assistants to customer support. The development of conversational AI systems is
supported by a large variety of software platforms, all with similar goals, but
different focus points and functionalities. A systematic foundation for
classifying conversational AI platforms is currently lacking. We propose a
framework for assessing the maturity level of conversational AI development
platforms. Our framework is based on a systematic literature review, in which
we extracted common and distinguishing features of various open-source and
commercial (or in-house) platforms. Inspired by language reference frameworks,
we identify different maturity levels that a conversational AI development
platform may exhibit in understanding and responding to user inputs. Our
framework can guide organizations in selecting a conversational AI development
platform according to their needs, as well as helping researchers and platform
developers improving the maturity of their platforms.Comment: 10 pages, 10 figures. Accepted for publication at SAC 2021:
ACM/SIGAPP Symposium On Applied Computin
A nonhomogeneous boundary value problem in mass transfer theory
We prove a uniqueness result of solutions for a system of PDEs of
Monge-Kantorovich type arising in problems of mass transfer theory. The results
are obtained under very mild regularity assumptions both on the reference set
, and on the (possibly asymmetric) norm defined in
. In the special case when is endowed with the Euclidean
metric, our results provide a complete description of the stationary solutions
to the tray table problem in granular matter theory.Comment: 22 pages, 2 figure
Boron Isotope Effect in Superconducting MgB
We report the preparation method of, and boron isotope effect for MgB, a
new binary intermetallic superconductor with a remarkably high superconducting
transition temperature (B) = 40.2 K. Measurements of both
temperature dependent magnetization and specific heat reveal a 1.0 K shift in
between MgB and MgB. Whereas such a high transition
temperature might imply exotic coupling mechanisms, the boron isotope effect in
MgB is consistent with the material being a phonon-mediated BCS
superconductor.Comment: One figure and related discussion adde
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