996 research outputs found
On a new class of Finsler metrics
In this paper, the geometric meaning of (alpha,beta)-norms is made clear. On
this basis, we introduce a new class of Finsler metrics called general
(alpha,beta)-metrics, which are defined by a Riemannian metric and an 1-form.
These metrics not only generalize original (alpha,beta)-metrics naturally, but
also include some metrics structured by R. Bryant.
The notion of general (alpha,beta)-metrics is one of the original ideas
belongs to the first author(another one is beta-deformations intruduced in the
paper "Deformations and Hilbert's Fourth Problem"). We believe that the
researches on general (alpha,beta)-metrics will enrich Finsler geometry and the
approaches offer references for further study. But it seems that the classical
methods suitable for (alpha,beta)-metrics may not be suitable for them, the
idea used in this paper, which is closely related to beta-deformations, is
non-classical. Any communication or suggestion is welcome.Comment: 16 page
Homogeneous geodesics in homogeneous Finsler spaces
In this paper, we study homogeneous geodesics in homogeneous Finsler spaces.
We first give a simple criterion that characterizes geodesic vectors. We show
that the geodesics on a Lie group, relative to a bi-invariant Finsler metric,
are the cosets of the one-parameter subgroups. The existence of infinitely many
homogeneous geodesics on compact semi-simple Lie group is established. We
introduce the notion of naturally reductive homogeneous Finsler space. As a
special case, we study homogeneous geodesics in homogeneous Randers spaces.
Finally, we study some curvature properties of homogeneous geodesics. In
particular, we prove that the S-curvature vanishes along the homogeneous
geodesics
Internal and external load during 8 v 8, 5 v 5 and 3 v 3 in Chinese elite youth male football players
Aim to investigate internal and external load in three different game formats (8v8, 5v5, 3v3
with 80 m2
per player) of small-sided games (SSG) in Chinese elite youth football players. Twenty-nine elite
male football players (age: 18.3 ± 0.5 years (mean ± SD), height: 175 ± 6 cm, weight: 65.5 ± 6.3 kg)
participated in randomized order in the three formats. Each session consisted of 20 min: 3v3 on a 24×20-m
pitch, 5v5 on a 32×25-m pitch, or 8v8 on a 40×32-m pitch all equalling 80 m2
per player. Each player was
recorded once in each format. Using GPS-units and heart rate belts and blood lactate measured the two kinds
of load. 8–10% higher total distance (P < 0.01) was observed in 8 v8 and 5v5 compared with 3v3 (1627 ± 240
and 1595 ± 243 m vs. 1477 ± 179 m, ES = 0.55–0.71). Higher distance (P < 0.001) was covered with high
speed running (HSR: > 14 km/h) in 8v8 and 5v5 than 3v3 (154 ± 94 m and 133 ± 59 m vs. 77 ± 35,
ES = 1.09–1.15), whereas very high speed running distance (> 21 km/h) was higher (P < 0.01) in 8v8 than
5 v 5 and 3 v 3 (15.2 ± 19.5 vs. 5.3 ± 6.7 and 1.0 ± 0.4 m, ES = 0.69–1.03) and in 5 v 5 than 3 v 3. No
difference was found between game formats in the number of intense accelerations nor intense decelerations.
Blood lactate (3.5 ± 2.3 vs. 2.8 ± 1.9 vs. 2.4 ± 1.5 mmol·L
-1, P = 0.201) and mean heart rate (155 ± 21
vs. 160 ± 11 vs. 157 ± 17 bpm, P = 0.254) was not different between 8v8, 5v5 and 3v3 game formats.
Distance covered in total and in highest speed zones was higher in SSG formats with more players, which,
however, did not lead to differences in internal load measured by heart rate and blood lactate
Kvedarkor
Bilag til oppgave: CD med lytteeksemplerUtforsking av stemmebruk, klang, teknikk og ornamentikk i folkesang i Nord-Norge. Formidling av folkemusikk/folkesang i kor via improvisasjon
Solving the human sustainability problem in short-termist societies
Society has so far failed to create a sustainable economic system because all conventional attempts to change the current paradigm lead to a short-term decline in the rate economic growth, resulting in higher inequality and unemployment, outcomes which are politically unacceptable. This article shows how to overcome this hurdle, by adopting 13 unconventional policies which reduce unemployment and inequality while cutting greenhouse-gas emissions, regardless of what happens to economic growth, and so allow for a gradual transition to a sustainable system in short-termist societies
Dragare, täckningsgrader och önskelådor
We came in contact with the project "Grönplan Danderyd" that aims to create a
green structure plan for a municipality of Stockholm called Danderyds kommun. Our
thesis is a part of this project and makes it's contribution through the gathering and
systematization of the knowledge of the functions of an urban green structure. It also
makes a contribution through suggesting how this knowledge can be applied during
the construction of an urban green structure plan.
We found that "Stadens parker och natur", published by the Swedish National board
of Housing, Building and Planning, was a recurrent source of information in the
green structure plans that we studied. We saw a need of complementary additions
and updates to the rather old report and found literature that adds the developments
of the last decade.
First of all we have chosen to make themes based on the functions of a green
structure that were presented by 'Stadens parker och natur'. The themes we suggest
that a greenplanning document manage are: Recreation, Pedagogies and Heath,
Biological Diversity, Green structure in the History of Building Cities, Cultural
Identity, the Health of the City, Biological Technology in the Municipality and Use
and the Users.
We found good examples of how to handle these themes in documents that handle
greenstructure planning from the municipalities of Göteborg, Strängnäs, Eskilstuna,
Malmö, Lund, Västerås and Uppsala. We interviewed one person involved in the
making of each one of these documents.
We suggest methods for how each theme can be reflected in a green structure plan.
We also made a visual comment on each theme that can be an inspiration and
facilitate discussions during the planning process. We came to the general conclusion
that most important when constructing an urban green structure plan is to base
it on the prerequisites of the city and to have documented goals for the planning
of the green structure. It is also useful to work beyond the boundaries within the
organization and concerning ownership of land. To involve the users of the green
structure in the planning process and to present the plan in a pedagogic manner adds
even more quality to the work
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