Nardini G.,DIISM |
Neri D.,Marche Polytechnic University |
WSEAS Transactions on Environment and Development | Year: 2014
Many workers perform their daily activities outdoors and many anatomical body sites are exposed to UV radiation. The effects of solar radiation on human health depend on the amount and type of radiation impinging on the body. This paper aims to investigate and analyse the diurnal UV radiation exposure at typical anatomical site for farm workers. The diurnal distribution in solar UV exposure at the nape of the neck, forearm, forehead and cheek of farm workers was measured at 15 min intervals for consecutive working days from January to July 2012. The anatomical site most exposed was the nape of the neck. The UV exposure at the nape of the neck indicates that when SEA is about 54°, it may receive maximal exposures depending also on the particular anatomical site orientation and body movements. To better understand the diurnal distribution and variation of UV exposure, a correlation between solar elevation angle and UV exposure was investigated. The correlations were determined for each anatomical body sites with a R2 in a range between the 0.87 and 0.99. Real time exposure data suggest that it is useful to remind workers of the UV radiation risks associated with spending increased time in the sun exposure.
Fort A.,DIISM |
Mugnaini M.,DIISM |
Reliability Engineering and System Safety | Year: 2015
In modern electronics and in electrical applications design is very important to be able to predict the actual product life or, at least, to be able to provide the end user with a reasonable estimate of such parameter. It is important to be able to define the availability as a key parameter because, although other performance indicators (as the mean time before failures MTBF or mean time to failure MTTF) exist, they are often misused. To study the availability of an electrical, electronic or an electromechanical system, different methods can be used. The most common one relies on memory-less Markovian state space analysis due to the fact that a little information is needed, and under simple hypothesis, it is possible to gather some outcomes on the availability of steady state value. In this paper the authors, starting from classical approach of Markov models, introduce an extension known as Hidden Markov Models approach to overcome the limits of the previous one in estimating the system availability performance over time. Such a technique can be used to improve the logistic aspects connected with optimal maintenance planning. The provided dissertation in general can be used in different contexts without losing in generality. © 2014 Elsevier B.V. All rights reserved.