Search results for " Air"
showing 10 items of 703 documents
Control of indoor environments in heritage buildings: experimental measurements in an old Italian museum and proposal of a methodology
2005
Abstract This paper describes some results from an experiment carried out regarding a procedure to be adopted for temperature and R.H. monitoring of indoor spaces designed for exhibiting events, such as museums and similar institutions. The monitored data employed in this study has been collected by the Department di Ricerche Energetiche ed Ambientali of the Universita degli Studi di Palermo in co-operation with the Regional Gallery ''Palazzo Abatellis'' of Palermo. The study analyses a simple method for characterising the environmental quality of museums so as to ensure the optimal conservation of works of art. This methodology is based on the procedure (where thermal and hygrometry parame…
The public and private use of space in Magdalenian societies: Evidence from Oelknitz 3, LOP (Thuringia, Germany)
2015
Abstract The site of Oelknitz (Thuringia, Germany) is among the largest and in terms of spatial organisation most complex Magdalenian open air sites known to date, rich in evident structures. The current paper reports evidence from the youngest, latest phase of occupation at Oelknitz Structure 3. It is demonstrated that this structure represents a dwelling construction characterised by different spatially distinct activity zones. Several hypotheses can be drawn from this evidence in order to understand basic principles on Magdalenians’ settlement behaviour and their social cohesion.
Indoor air quality of everyday use spaces dedicated to specific purposes—a review
2017
According to literature data, some of the main factors which significantly affect the quality of the indoor environment in residential households or apartments are human activities such as cooking, smoking, cleaning, and indoor exercising. The paper presents a literature overview related to air quality in everyday use spaces dedicated to specific purposes which are integral parts of residential buildings, such as kitchens, basements, and individual garages. Some aspects of air quality in large-scale car parks, as a specific type of indoor environment, are also discussed. All those areas are characterized by relatively short time use. On the other hand, high and very high concentration level…
Visually low-impacting methods for the measurement of parameters related to IAQ risk indicators in exhibition halls
2021
Microclimate for cultural heritage plays a fundamental role in the degradation process of artefacts exhibited in museums. Generally, the Indoor Air Quality (IAQ) monitoring inside museums is based on conventional measurements of thermo-hygrometry parameters and longtime averaged measurements of atmospheric pollutants’ concentration. Unfortunately, all these approaches require electric supply and are usually characterized by a noticeable visual impact on the exhibition space, which clearly negatively affects the visitors’ experience. This paper intends to revisit and discuss a methodology (and its test application on field, to estimate the risk of damage of three artefacts displayed in an ol…
Quantitative EEG during Early Recovery from Hypoxic-Ischemic Injury in Immature Piglets: Burst Occurrence and Duration
1999
This study examined the course of EEG recovery in an animal model of hypoxic-ischemic injury. The model used periods of hypoxia, room air and asphyxia to induce cardiac arrest. One-week-old piglets (n = 16) were exposed to a period of hypoxia, room air and complete asphyxia for 7 minutes. After cardiac arrest and resuscitation, two EEG features were evaluated as prognostic indicators of behavioral outcome as assessed by a neuroscore at 24 hours after insult. A prominent EEG feature was the number and duration of bursts evident during recovery. Episodes of bursting were detected through the thresholds on sustained periods of elevated power. After the animal was resuscitated, the EEG was moni…
Reconstruction of inclined air showers detected with the Pierre Auger Observatory
2014
We describe the method devised to reconstruct inclined cosmic-ray air showers with zenith angles greater than $60^\circ$ detected with the surface array of the Pierre Auger Observatory. The measured signals at the ground level are fitted to muon density distributions predicted with atmospheric cascade models to obtain the relative shower size as an overall normalization parameter. The method is evaluated using simulated showers to test its performance. The energy of the cosmic rays is calibrated using a sub-sample of events reconstructed with both the fluorescence and surface array techniques. The reconstruction method described here provides the basis of complementary analyses including an…
Muons in air showers at the Pierre Auger Observatory: Measurement of atmospheric production depth
2014
The surface detector array of the Pierre Auger Observatory provides information about the longitudinal development of the muonic component of extensive air showers. Using the timing information from the flash analog-to-digital converter traces of surface detectors far from the shower core, it is possible to reconstruct a muon production depth distribution. We characterize the goodness of this reconstruction for zenith angles around 60° and different energies of the primary particle. From these distributions, we define Xμmax as the depth along the shower axis where the production of muons reaches maximum. We explore the potentiality of Xμmax as a useful observable to infer the mass compositi…
Description of atmospheric conditions at the Pierre Auger Observatory using the Global Data Assimilation System (GDAS)
2012
Atmospheric conditions at the site of a cosmic ray observatory must be known for reconstructing observed extensive air showers. The Global Data Assimilation System (GDAS) is a global atmospheric model predicated on meteorological measurements and numerical weather predictions. GDAS provides altitude-dependent profiles of the main state variables of the atmosphere like temperature, pressure, and humidity. The original data and their application to the air shower reconstruction of the Pierre Auger Observatory are described. By comparisons with radiosonde and weather station measurements obtained on-site in Malargüe and averaged monthly models, the utility of the GDAS data is shown.
Gamma-Ray Flares from Mrk421 in 2008 observed with the ARGO-YBJ detector
2010
In 2008 the blazar Markarian 421 entered a very active phase and was one of the brightest sources in the sky at TeV energies, showing frequent flaring episodes. Using the data of ARGO-YBJ, a full coverage air shower detector located at Yangbajing (4300 m a.s.l., Tibet, China), we monitored the source at gamma ray energies E > 0.3 TeV during the whole year. The observed flux was variable, with the strongest flares in March and June, in correlation with X-ray enhanced activity. While during specific episodes the TeV flux could be several times larger than the Crab Nebula one, the average emission from day 41 to 180 was almost twice the Crab level, with an integral flux of (3.6 +-0.6) 10^-1…
Mixed-Phase Clouds: Progress and Challenges
2017
Mixed-phase clouds represent a three-phase colloidal system consisting of water vapor, ice particles, and coexisting supercooled liquid droplets. Mixed-phase clouds are ubiquitous in the troposphere, occurring at all latitudes from the polar regions to the tropics. Because of their widespread nature, mixed-phase processes play critical roles in the life cycle of clouds, precipitation formation, cloud electrification, and the radiative energy balance on both regional and global scales. Yet, in spite of many decades of observations and theoretical studies, our knowledge and understanding of mixed-phase cloud processes remains incomplete. Mixed-phase clouds are notoriously difficult to represe…