1,798 research outputs found
Dynamic nozzles for drop generators
received: 2015-06-03 accepted: 2015-10-16 published: 2015-11-03received: 2015-06-03 accepted: 2015-10-16 published: 2015-11-03This work was funded by the UK Engineering and Physical Sciences Research Council (Grant No. EP/H018913/1), the John Fell Oxford University Press Research Fund, and the Royal Society
On Hirschman and log-Sobolev inequalities in mu-deformed Segal-Bargmann analysis
We consider a deformation of Segal-Bargmann space and its transform. We study
L^p properties of this transform and obtain entropy-entropy inequalities
(Hirschman) and entropy-energy inequalities (log-Sobolev) that generalize the
corresponding known results in the undeformed theory.Comment: 42 pages, 3 figure
Discovery of Very High Energy gamma - ray emission from the extreme BL Lac object H2356-309 with H.E.S.S
The understanding of acceleration mechanisms in active galactic nuclei (AGN)
jets and the measurement of the extragalactic-background-light (EBL) density
are closely linked and require the detection of a large sample of
very-high-energy (VHE) emitting extragalactic objects at varying redshifts. We
report here on the discovery with the H.E.S.S. (High Energy Stereoscopic
System) atmospheric-Cherenkov telescopes of the VHE Gamma-ray emission from
H2356 - 309, an extreme BL Lac object located at a redshift of 0.165. The
observations of this object, which was previously proposed as a
southern-hemisphere VHE candidate source, were performed between June and
December 2004. The total exposure is 38.9 hours live time, after data quality
selection, which yields the detection of a signal at the level of 9.0
(standard deviations) .Comment: To appear on proceeding of 29th International Cosmic Ray Conference
(ICRC 2005
Optical-NIR spectroscopy of the puzzling gamma-ray source 3FGL 1603.9-4903/PMN J1603-4904 with X-shooter
The Fermi/LAT instrument has detected about two thousands Extragalactic High
Energy (E > 100 MeV) gamma-ray sources. One of the brightest is 3FGL
1603.9-4903, associated to the radio source PMN J1603-4904. Its nature is not
yet clear, it could be either a very peculiar BL Lac or a CSO (Compact
Symmetric Object) radio source, considered as the early stage of a radio
galaxy. The latter, if confirmed, would be the first detection in gamma-rays
for this class of objects. Recently a redshift z=0.18 +/- 0.01 has been claimed
on the basis of the detection of a single X-ray line at 5.44 +/- 0.05 keV
interpreted as a 6.4 keV (rest frame) fluorescent line. We aim to investigate
the nature of 3FGL 1603.9-4903/PMN J1603-4904 using optical to NIR
spectroscopy. We observed PMN J1603-4904 with the UV-NIR VLT/X-shooter
spectrograph for two hours. We extracted spectra in the VIS and NIR range that
we calibrated in flux and corrected for telluric absorption and we
systematically searched for absorption and emission features. The source was
detected starting from ~6300 Ang down to 24000 Ang with an intensity comparable
to the one of its 2MASS counterpart and a mostly featureless spectrum. The
continuum lacks absorption features and thus is non-stellar in origin and
likely non-thermal. On top of this spectrum we detected three emission lines
that we interpret as the Halpha-[NII] complex, the [SII] 6716,6731 doublet and
the [SIII] 9530 line, obtaining a redshift estimate of z= 0.2321 +/- 0.0004.
The equivalent width of the Halpha-[NII] complex implies that PMN J1603-4904
does not follow the observational definition of BL Lac, the line ratios suggest
that a LINER/Seyfert nucleus is powering the emission. This new redshift
measurement implies that the X-ray line previously detected should be
interpreted as a 6.7 keV line which is very peculiar.Comment: Published in Astronomy and Astrophysic
A Spectacular VHE Gamma-Ray Outburst from PKS 2155-304 in 2006
Since 2002 the VHE (>100 GeV) gamma-ray flux of the high-frequency peaked BL
Lac PKS 2155-304 has been monitored with the High Energy Stereoscopic System
(HESS). An extreme gamma-ray outburst was detected in the early hours of July
28, 2006 (MJD 53944). The average flux above 200 GeV observed during this
outburst is ~7 times the flux observed from the Crab Nebula above the same
threshold. Peak fluxes are measured with one-minute time scale resolution at
more than twice this average value. Variability is seen up to ~600 s in the
Fourier power spectrum, and well-resolved bursts varying on time scales of ~200
seconds are observed. There are no strong indications for spectral variability
within the data. Assuming the emission region has a size comparable to the
Schwarzschild radius of a ~10^9 solar mass black hole, Doppler factors greater
than 100 are required to accommodate the observed variability time scales.Comment: 4 pages, 3 figures; To appear in the Proceedings of the 30th ICRC
(Merida, Mexico
Keberadaan Keyboard Pada Gendang Guro-guro Aron Dan Pengaruhnya Terhadap Karakter Muda- Mudi Karo
Perubahan yang terjadi dalam kesenian tradisional Karo adalah Perubahan pemakaian alat musik, yaitu alat musik tradisional digantikan oleh satu alat musik barat yang dikenal dengan nama keyboard. Perubahan tersebut menimbulkan akulturasi di dalam seni pertunjukan tradisional Karo. Hadirnya musik keyboard memunculkan masalah yang baru pada satu sisi, yaitu masalah etika menjadi tidak diperhatikan bagi muda-mudi Karo sebagai penerus budaya Karo. Tata cara menari yang semakin seronok dan serampangan sering terjadi dengan atau tanpa sengaja oleh komunitas pendukungnya
Avaliação do efeito do corte horizontal da copa, com máquina de podar de discos, em pomares de pera “Rocha
Current pear pruning making use of pneumatic shears still is a very labour intensive operation. The Proder project “Avaliação da poda mecânica em pomares de pera” was designed to contribute to solutions that would reduce the present dependence in labour and therefore to promote a reduction in pruning costs. This paper shows the results of a trial made to evaluate the influence of mechanical topping in manual pruning complement field work and pear yield. Topping was performed using a Reynolds 6DT 3.0m cutting bar with six hydraulic-driven circular disc-saws mounted in the three point tractor linkage system. The field trial was performed in a commercial orchard with 20 years, planted in an array of 4m x 2m with tree lines oriented in North-South direction. Trees were trained as the central leader system. In this trial, in a randomised complete block design with four replications, two treatments are being compared leading to 8 plots with one line of 14 trees per plot. The treatments tests were: T1 - manual pruning performed by workers using pneumatic shears, in each year; T2 - Topping the canopy parallel to the ground, using a discs-saw pruning machine mounted in a front loader of an agricultural tractor, followed by manual pruning complement performed by workers with pneumatic shears. Tree height and width was measured, before and after pruning. Work was timed and pear yields evaluated. Mechanical topping seems to be effective in the control of tree height, which can contribute to increase 14% of work rates on manual pruning complement. No significant differences in pear yield were found between treatments
Reservas de Caza en España: la gestión pública de la caza
In Spain, Game Reserves (GR) are territorial public hunting management units that cover 3.5% of the country and ~ 10% of the Natura 2000 Network. The first GR were established in 1966 and by 2011 there were 49. Their primary purposes were to promote wild ungulate populations, their sustainable use, and to provide social, economic, and recreational benefits to local communities and hunters, generally. During the 1980s following a political federalization process, GR became the responsibility of regional governments and their role has never been evaluated, even though the political, rural ecological, and administrative frameworks underwent substantial changes. In this paper, we present a review of the state of GR in 2011, identify their successes and problems, and provide recommendations for the future. The GR have been fundamental to sustainable hunting and the protection of wildlife, particularly, game species. Currently, their virtues are not widely appreciated and they do not receive sufficient financial and human resources to meet their objective fully. We propose several initiatives that might improve the use of existing resources and increase the profile of these publicly managed areas.Las Reservas de Caza (RC) constituyen una figura de gestión cinegética pública del territorio en España. Abarcan el 3.5% del territorio y ocupan aproximadamente el 10% de la Red Natura 2000. Su declaración comenzó en 1966, y desde entonces no ha cesado, llegando en la actualidad a las 49 RC. Fueron creadas esencialmente para la promoción de las poblaciones de ungulados silvestres, el aprovechamiento ordenado de este recurso y la satisfacción social, económica y recreativa de las comunidades locales y de los cazadores en general. Quedaron fuera de la tutela del estado tras su descentralización a partir de principios de los años ochenta del pasado siglo, y su función en conjunto no ha sido nunca evaluada, al tiempo que el panorama político, rural, ecológico y administrativo ha sufrido profundos cambios. Este artículo pretende ofrecer una panorámica actualizada de la situación de las RC a principios del siglo XXI, evaluar sus logros y problemática actual, así como proponer algunas actuaciones para el futuro inmediato. Las RC han sido pioneras en el aprovechamiento sostenible de la caza y de gran utilidad para la protección de la fauna en general y las especies cinegéticas en concreto. Actualmente no gozan del reconocimiento popular, y no reciben los recursos necesarios económicos y humanos suficientes para seguir cumpliendo su función adecuadamente. Se proponen una serie de medidas para aprovechar mejor los recursos disponibles y poder dar a conocer a la sociedad el valor de estos terrenos de gestión pública
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