Brayton cycle 3.2-inch radial compressor performance evaluation

Brayton cycle 3.2 inch radial compressor performance evaluation over wide range of Reynolds number

Simulation of UHE muons propagation for GEANT3

A simulation package for the transport of high energy muons has been developed. It has been conceived to replace the muon propagation software modules implemented in the detector simulation program GEANT3. Here we discuss the results achieved with our package and we check the agreement with numerical calculations up to 10**8 GeV.Comment: 21 pages, 6 figures, 1 Table. AMSTeX document, acknowledgments adde

Neutrino Propagation Through Matter

We discuss a simple approach to solve the transport equation for high-energy neutrinos in media of any thickness. We present illustrative results obtained with some specific models for the initial spectra of muon neutrinos and antineutrinos propagating through a normal cold medium

Heat stress affects reproductive performance of high producing dairy cows bred in an area of southern Apennines

A 5-year retrospective (from 2008 to 2012) survey was carried out by analyzing data of high producing dairy cows reared in farms located in an area of southern Apennines. The indicators of fertility obtained were related to either season variations or the temperature-humidity index (THI). A significant lower number of conceptions evaluated per month on an annual basis (NCY), i.e., a parameter obtained by subtracting gestation length to the calving date, was found during the summer months; furthermore, this parameter decreased along with THI increase. The number of heats detected varied equally to NCY and represented the main cause of the lower fertility consequent to heat stress (HS). The age at first calving was not significantly affected by either the season or the THI. The mean number of AI/pregnancy in relation to the calving time was significantly affected by the season but it was not related to THI. The number of days open was significantly larger in the animals calved from January to July than from August to December (163±33 vs 123±36 days; P< 0.001); this causes an annual economic loss of several thousand euro in each farm analyzed. In conclusion, HS causes severe economic losses in dairy farms located in southern Apennines that are mainly due to a lower number of heats detected as well as a larger number of days open and semen doses used

Ionospheric precursors for crustal earthquakes in Italy

Crustal earthquakes with magnitude 6.0&gt;M&ge;5.5 observed in Italy for the period 1979–2009 including the last one at L'Aquila on 6 April 2009 were considered to check if the earlier obtained relationships for ionospheric precursors for strong Japanese earthquakes are valid for the Italian moderate earthquakes. The ionospheric precursors are based on the observed variations of the sporadic E-layer parameters (<I>h</I>'Es, <I>fb</I>Es) and <I>fo</I>F2 at the ionospheric station Rome. Empirical dependencies for the seismo-ionospheric disturbances relating the earthquake magnitude and the epicenter distance are obtained and they have been shown to be similar to those obtained earlier for Japanese earthquakes. The dependences indicate the process of spreading the disturbance from the epicenter towards periphery during the earthquake preparation process. Large lead times for the precursor occurrence (up to 34 days for M=5.8–5.9) tells about a prolong preparation period. A possibility of using the obtained relationships for the earthquakes prediction is discussed

Visibility analysis of boundary layer transition

We study the transition to turbulence in a flat plate boundary layer by means of visibility analysis of velocity time-series extracted across the flow domain. By taking into account the mutual visibility of sampled values, visibility graphs are constructed from each time series. The latter are, thus, transformed into a geometrical object, whose main features can be explored using measures typical of network science that provide a reduced order representation of the underlying flow properties. Using these metrics, we observe the evolution of the flow from laminarity to turbulence and the effects exerted by the free-stream turbulence. Different from other methods requiring an extensive amount of spatiotemporal data (e.g., full velocity field) or a set of parameters and thresholds arbitrarily chosen by the user, the present network-based approach is able to identify the onset markers for transition by means of the streamwise velocity time-series alone. Published under an exclusive license by AIP Publishing