Search results for "Sky"
showing 10 items of 1603 documents
Results of a self-triggered prototype system for radio-detection of extensive air showers at the Pierre Auger Observatory
2012
We describe the experimental setup and the results of RAuger, a small radio-antenna array, consisting of three fully autonomous and self-triggered radio-detection stations, installed close to the center of the Surface Detector (SD) of the Pierre Auger Observatory in Argentina. The setup has been designed for the detection of the electric field strength of air showers initiated by ultra-high energy cosmic rays, without using an auxiliary trigger from another detection system. Installed in December 2006, RAuger was terminated in May 2010 after 65 registered coincidences with the SD. The sky map in local angular coordinates (i.e., zenith and azimuth angles) of these events reveals a strong azi…
Airborne observations of far-infrared upwelling radiance in the Arctic
2016
Abstract. The first airborne measurements of the Far-InfraRed Radiometer (FIRR) were performed in April 2015 during the panarctic NETCARE campaign. Vertical profiles of spectral upwelling radiance in the range 8–50 μm were measured in clear and cloudy conditions from the surface up to 6 km. The clear-sky profiles highlight the strong dependence of radiative fluxes to the temperature inversion typical of the Arctic. Measurements acquired for total column water vapor from 1.5 to 10.5 mm also underline the sensitivity of the far-infrared greenhouse effect to specific humidity. The cloudy cases show that optically thin ice clouds increase the cooling rate of the atmosphere by a factor up to thr…
The starry sky, a territorial commons?
2021
International audience; Flagstaff, Arizona, United States, April 15, 1958: the city council adopts the ordinance n°440 which aims at “preventing a rapid deterioration of the visibility of the starry sky”. This regulation results from the mobilization of the Lowell Observatory astronomers against certain public lighting devices. Through this political act, the elected officials place their city at the epicenter of an emergent international movement: the ‘Dark-sky movement’. The first replica of this movement is felt in 1972 in Tucson, Arizona. From a discomfort perceived by astronomers from the Lowell and Kitt Peak observatories, the idea of ‘light pollution’ emerges and begins to spread thr…
Stravinski et ses interprètes. 90 ans d'enregistrements du Sacre du printemps
2022
A work originally composed for ballet, Igor Stravinsky's The Rite of Spring paradoxically owes its reputation to its concert performances and the plethora of discographic versions. As David Zinman says, The Rite is "a kind of visiting card" with which "conductors can demonstrate their personal artistic attitudes." As a result, The Rite is one of the composer's most recorded works, with over 180 recordings of the orchestral version. Stravinsky considered his own recordings to establish an authoritative performance model. CBS even used this as a selling point by putting the slogan "Stravinsky conducts Stravinsky" on the covers of his records. However, his interpretations do not always respect…
Lutte ouvrière, monolithe du trotskysme ?
2014
International audience
A simple method for estimating downward longwave radiation from surface and satellite data by clear sky
1990
Abstract An attempt to derive downward longwave radiation at the surface in clear sky conditions is presented. A method that integrates satellite-measured infrared radiation temperatures with ground measurements of water vapour pressure is applied to Meteosat data. Satellite-derived fluxes are compared with corresponding ground-measured fluxes at three different sites in France and during various seasons. Comparison of the daily averaged fluxes shows a correlation coefficient of 0–88 and an r.m.s. difference between satellite estimates and ground measurements of 12 Wm-2.
Combining omnidirectional vision with polarization vision for robot navigation
2012
Polarization is the phenomenon that describes the oscillations orientations of the light waves which are restricted in direction. Polarized light has multiple uses in the animal kingdom ranging from foraging, defense and communication to orientation and navigation. Chapter (1) briefly covers some important aspects of polarization and explains our research problem. We are aiming to use a polarimetric-catadioptric sensor since there are many applications which can benefit from such combination in computer vision and robotics specially robot orientation (attitude estimation) and navigation applications. Chapter (2) mainly covers the state of art of visual based attitude estimation.As the unpol…
Searches for anisotropies in the arrival directions of the highest energy cosmic rays detected by the Pierre Auger Observatory
2015
We analyze the distribution of arrival directions of ultra-high energy cosmic rays recorded at the Pierre Auger Observatory in 10 years of operation. The data set, about three times larger than that used in earlier studies, includes arrival directions with zenith angles up to $80^\circ$, thus covering from $-90^\circ$ to $+45^\circ$ in declination. After updating the fraction of events correlating with the active galactic nuclei (AGNs) in the V��ron-Cetty and V��ron catalog, we subject the arrival directions of the data with energies in excess of 40 EeV to different tests for anisotropy. We search for localized excess fluxes and for self-clustering of event directions at angular scales up t…
Effects of added endurance or strength training on cardiovascular and neuromuscular performance of conscripts during the 8-week basic training period
2010
The present series of studies investigated changes in Finnish conscripts’ body composition, aerobic fitness and muscle endurance profiles during the last three decades. A second aim was to examine the effects of added endurance (ET) or strength training (ST) on cardiovascular and neuromuscular performance as well as hormonal responses of conscripts during an 8-week basic training (BT) period when compared to the current standardized (NT) programme. The third aim was to study the effects of these three different training programmes on a novel 3K combat running performance test. The present results showed that aerobic fitness and muscle endurance of 20 year old men in Finland has decreased a…
Proposed Protocol for Field Testing of Endurance Fitness of Young Labrador Retrievers
2023
The number of dogs and, with it, dog sports are growing in popularity, and the training of dogs begins at an early age. Although fitness testing is an imperative part of purposeful training and sports, to our knowledge, no objective field tests are available for measuring young dogs’ endurance fitness. The aim of this study is to describe a simple, easy-to-repeat, and inexpensive way to test training intervention effects on endurance fitness in young Labrador Retrievers. Healthy client-owned 16-week-old Labrador Retrievers will be recruited and divided into test and control groups. The test group will have an eight-week training program followed by a four-week detraining period, while the c…