In this article, we report the design of a reflective intensity-modulated optical fiber sensor for blade tip-clearance measurement, and the experimental results for the first stage of a compressor of an aircraft engine operating in real conditions. The tests were performed in a ground test cell, where the engine completed four cycles from idling state to takeoff and back to idling state. During...

In this study, ventilation of clothing microenvironment, thermal insulation and vapor resistance of two jackets made of different materials were measured locally at front, back, side and arm by using an articulated thermal manikin in a controlled climate chamber (29±1°C, 40±10%RH). The various conditions of microenvironment ventilation were created by making the manikin stand and walk, combined...

In the current study, a multi-arc predicting model for DC critical flashover voltage of iced and pre-contaminated long insulator strings under low atmospheric pressure is developed. The model is composed of a series of different polarity surface arcs, icicle-icicle air gap arcs, and residual layer resistance. The calculation method of the residual resistance of the ice layer under DC multi-arc ...

The aim of the work was examination of the dielectric properties of a new type of polymer nanocomposites based on PVDF (polyvinylidene fluoride), or a copolymer P(VDF-HFP) with addition of ferrite nanoparticles. The addition of nanofillers leads not only to the formation of polar -phase of PVDF, which shows unique piro-, piezoand ferroelectric properties used in many applications, but also aff...

During the past decades, Ocean Bottom Seismometers (OBS) have played a key role in permanent seismic activity monitoring at sea as well as allowing a better understating of the earth interior. Data collected by the instrument can provide information on the ocean bottom sub-layers down to a depth of 40 km beneath the ocean floor. The accuracy of the results directly depends on the time drift of ...

Clouds, a key component of the climate system, form when water vapor condenses upon atmospheric particulates termed Cloud Condensation Nuclei (CCN). Variations in CCN concentrations can profoundly impact cloud properties, with important effects on local and global climate. Organic matter (OM) constitutes a significant fraction of tropospheric aerosol mass, and can influence CCN activity by depr...

Deformation of the material during cyclic expansion extrusion (CEE) is investigated using upper-bound theorem. The analytical approximation of forming loads agrees very well with the FEM results for different amounts of chamber diameter, friction factor and also for lower die angles. However, the difference between analytical and numerical solution increases at higher die angles which are expla...

The performances of outdoor polymeric insulators are influenced by environmental conditions. The use of polymeric materials in a particular composition can be produced insulators that are resistant to environmental influences. This paper presents the effect of artificial tropical climate on the hydrophobicity, equivalent salt deposit density (ESDD), surface leakage current, flashover voltage, a...

Climate change influences the distribution of species, causing the displacement of distribution areas, both in altitude and latitude. The potentially most climate change-susceptible taxa are those of mountain peaks, with limited distribution areas, such as rare or endemic species. In this paper, we deepened the study of Androsace mathildae Levier, a plant that lives in Central Italy over 2500 m...

We examined the effect of climate on aboveground biomass allocation of ponderosa pine (Pinus ponderosa) by measuring trees in disjunct forest stands growing on the same substrate at high-elevation montane sites and low-elevation desert sites. Climatic differences between the sites were comparable to the difference between present and future climates of interior North America that is expected to...