Search results for "SPEED"
showing 10 items of 876 documents
A simple model to estimate the daily value of the regional maximum evapotranspiration from satellite temperature and albedo images
1987
Abstract We have tried an adaptation of the radiation model proposed by FAO, applicable in any area, for the estimation of the regional maximum evapotranspiration, ET, from temperature and albedo images obtained from a satellite. This model is based on the relationships ETm = k cETo ETo = A + BR g + CR g Ta max where k c is the crop coefficient, ETo is the maximum evapotranspiration of the reference crop (green grass), Rg is the global radiation obtained from satellite albedo images, T a max is the maximum temperature of the air obtained from the near-midday satellite temperature and A, B and C are the empirical coefficients characteristic of each zone calculated for different intervals of …
Measurement of the Atmospheric ve flux in IceCube
2012
We report the first measurement of the atmospheric electron neutrino flux in the energy range between approximately 80 GeV and 6 TeV, using data recorded during the first year of operation of IceCube's DeepCore low energy extension. Techniques to identify neutrinos interacting within the DeepCore volume and veto muons originating outside the detector are demonstrated. A sample of 1029 events is observed in 281 days of data, of which 496 $\pm$ 66(stat.) $\pm$ 88(syst.) are estimated to be cascade events, including both electron neutrino and neutral current events. The rest of the sample includes residual backgrounds due to atmospheric muons and charged current interactions of atmospheric muo…
Environmental Data Processing by Clustering Methods for Energy Forecast and Planning
2011
This paper presents a statistical approach based on the k-means clustering technique to manage environmental sampled data to evaluate and to forecast of the energy deliverable by different renewable sources in a given site. In particular, wind speed and solar irradiance sampled data are studied in association to the energy capability of a wind generator and a photovoltaic (PV) plant, respectively. The proposed method allows the sub-sets of useful data, describing the energy capability of a site, to be extracted from a set of experimental observations belonging the considered site. The data collection is performed in Sicily, in the south of Italy, as case study. As far as the wind generation…
A Novel Self-organizing Neural Technique for Wind Speed Mapping
2009
Systems with high nonlinearities are, in general, very difficult to model. This is particularly true in geostatistics, where the problem of the estimation of a regionalized variable (RV) given only a small amount of measurement stations and a complex terrain surface is very challenging. This paper introduces a novel strategy, which couples the Curvilinear Component Analysis (CCA) and the Generalized Mapping Regressor (GMR). CCA, which is a nonlinear projector of a data manifold, is here used in order to find the intrinsic dimension of the data manifold, just giving an insight on the nonlinearities of the problem. This analysis drives the pre-processing of the data set used for the training …
A Selective Change Driven System for High-Speed Motion Analysis.
2016
Vision-based sensing algorithms are computationally-demanding tasks due to the large amount of data acquired and processed. Visual sensors deliver much information, even if data are redundant, and do not give any additional information. A Selective Change Driven (SCD) sensing system is based on a sensor that delivers, ordered by the magnitude of its change, only those pixels that have changed most since the last read-out. This allows the information stream to be adjusted to the computation capabilities. Following this strategy, a new SCD processing architecture for high-speed motion analysis, based on processing pixels instead of full frames, has been developed and implemented into a Field …
The HisClima database: historical weather logs for automatic transcription and information extraction
2021
Knowing the weather and atmospheric conditions from the past can help weather researchers to generate models like the ones used to predict how weather conditions are likely to change as global temperatures continue to rise. Many historical weather records are available from the past registered on a systemic basis. Historical weather logs were registered in ships, when they were on the high seas, recording daily weather conditions such as: wind speed, temperature, coordinates, etc. These historical documents represent an important source of knowledge with valuable information to extract climatic information of several centuries ago. This paper presents a database for researching about the ca…
Daytime sensible heat flux estimation over heterogeneous surfaces using multitemporal land-surface temperature observations
2016
Equations based on surface renewal (SR) analysis to estimate the sensible heat flux (H) require as input the mean ramp amplitude and period observed in the ramp-like pattern of the air temperature measured at high frequency. A SR-based method to estimate sensible heat flux (HSR-LST) requiring only low-frequency measurements of the air temperature, horizontal mean wind speed, and land-surface temperature as input was derived and tested under unstable conditions over a heterogeneous canopy (olive grove). HSR-LST assumes that the mean ramp amplitude can be inferred from the difference between land-surface temperature and mean air temperature through a linear relationship and that the ramp freq…
Witnessing non-Markovian effects of quantum processes through Hilbert-Schmidt speed
2020
Non-Markovian effects can speed up the dynamics of quantum systems while the limits of the evolution time can be derived by quantifiers of quantum statistical speed. We introduce a witness for characterizing the non-Markovianity of quantum evolutions through the Hilbert-Schmidt speed (HSS), which is a special type of quantum statistical speed. This witness has the advantage of not requiring diagonalization of evolved density matrix. Its sensitivity is investigated by considering several paradigmatic instances of open quantum systems, such as one qubit subject to phase-covariant noise and Pauli channel, two independent qubits locally interacting with leaky cavities, V-type and $\Lambda $-typ…
Influence of position of the context sensitive graphemes and word frequency effect on reading speed: a performance analysis of developmental dyslexic…
2011
Several studies have reported how the presence of contextual letter-sound conversion rules influences both reading speed and accuracy and the effect of rule complexity holds for low frequency words only. We aimed to investigate the role of orthography complexity and, in particular, of context sensitive graphemes position and frequency of use on reading speed, analyzing the performance of developmental dyslexics and fluent readers. With regard to speed (reading speed of word lists), context sensitive graphemes position had an effect only for dyslexic children, who showed the worst performance if the context sensitive graphemes were in first position, regardless of word frequency. On the othe…
Residents’corner June 2014. PhotogRaphic Clues: Best Settings for Dermatologic Photography
2014
Obtaining digital images either for documentation or research purposes is a daily need for the dermatologist. Photography, as the art of capturing light, relies mainly on three modifiable elements: lens aperture (defined as the opening through which light reaches the camera sensor; expressed as “F-stops”, the smaller the number, the broader the aperture), shutter speed (the total time during which light reaches the sensor; it is indicated as fractions of a second) and ISO sensitivity (the light [...]