4,523,514 research outputs found
Reply to Comment on 'Critical behaviour in the relaminarization of localized turbulence in pipe flow'
This is a Reply to Comment arXiv:0707.2642 by Hof et al. on Letter
arXiv:physics/0608292 which was subsequently published in Phys Rev Lett, 98,
014501 (2007).
In our letter it was reported that in pipe flow the median time for
relaminarisation of localised turbulent disturbances closely follows the
scaling . This conclusion was based on data from
collections of 40 to 60 independent simulations at each of six different
Reynolds numbers, Re. In the Comment, Hof et al. estimate differently
for the point at lowest Re. Although this point is the most uncertain, it forms
the basis for their assertion that the data might then fit an exponential
scaling , for some constant A, supporting Hof et al.
(2006) Nature, 443, 59. The most certain point (at largest Re) does not fit
their conclusion and is rejected. We clarify why their argument for rejecting
this point is flawed. The median is estimated from the distribution of
observations, and it is shown that the correct part of the distribution is
used. The data is sufficiently well determined to show that the exponential
scaling cannot be fit to the data over this range of Re, whereas the fit is excellent, indicating critical behaviour and supporting
experiments by Peixinho & Mullin 2006.Comment: 1 page, 1 figur
Jobs from Renewable Energy and Energy Efficiency
According to research by Roger Bezdek for the American Solar Energy Society (ASES), the renewable energy (RE) and energy efficiency (EE) industries created a total of 8.5 million jobs (direct and indirect) in 2006; 450,000 jobs in RE and 8 million jobs in EE throughout the United States. As many as 1 out of 4 workers in the United States will be working in RE or EE industries by 2030. The 40 million jobs are not just engineering?related, but also include millions of new jobs in manufacturing, construction, accounting, and management.
Comment on "187Re(gamma,n) cross section close to and above the neutron threshold"
The work of M\"uller et al. [Phys. Rev. C 73, 025804 (2006);
astro-ph/0512603] provides interesting experimental data on neutron emission by
photodisintegration of 187Re. However, the comparison to theory and the
discussed implications for the Re/Os clock require considerable amendment.Comment: 2 pages; accepted for publication in Phys. Rev.
Finance for Renewable Energy: An Empirical Analysis of Developing and Transition Economies
This paper examines the role of the financial sector in renewable energy (RE) development. Although RE can bring socio-economic and environ- mental benefits, its implementation faces a number of obstacles, especially in non-OECD countries. One of these obstacles is financing: underdevel- oped financial sectors are unable to efficiently channel loans to RE produc- ers. The influence of financial sector development on the use of renewable energy resources is confirmed in panel data estimations on up to 119 non- OECD countries for 1980-2006. Financial intermediation, in particular commercial banking, has a significant positive effect on the amount of RE produced, and the impact is especially large when we consider non- hydropower RE such as wind, solar, geothermal, and biomass. There is also evidence that the adoption of the Kyoto Protocol has had a significant positive impact on the development of the RE sector.renewable energy, financial sector, banking, development
Astrophysical parameters of ten poorly studied open star clusters
We present here the fundamental parameters of ten open star clusters,
nominated from Kronberger et al. (2006) who presented some new discovered
stellar groups on the basis of 2MASS photometry and DSS visual images. Star
counts and photometric parameters (radius, membership, distances, color excess,
age, luminosity function, mass function, total mass, and the dynamical
relaxation time) have been determined for these ten clusters for the first
time. In order to calibrate our procedures, the main parameters (distance, age,
and color excesses) have been re-estimated for another five clusters, which are
studied by Kronberger et al. (2006) as well.Comment: 10 pages, 5 figures, 2 tables; accepted in "Research in Astronomy and
Astrophysics Journal
"It is the economy, companheiro!": an empirical analysis of Lula's re-election based on municipal data
This paper discusses the reasons that led to the Lula's 2006 re-election. Spatial analysis methods revealed that, contrary to 2002, the President had more votes in less developed municipalities of Brazil. The econometric results cast doubt on the analyses that attribute to Bolsa FamÃlia Programme total responsibility for the re-election. Lula''s electoral success results from changes in the labor market, low inflation and an export boom that have reduced inequality and improved the real wages of the Brazilian poor.
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