1,721,292 research outputs found
Compact Electromechanical Actuators for Urban Air Mobility: Development of a Framework for Design, Digital Twin and PHM Integration in eVTOL Aircrafts
No full textL'abstract è presente nell'allegato / the abstract is in the attachmen
Design and commissioning of a rotating test facility simulating a LPT hub cavity system for the investigation of cavity flows in aeroengines
No full textDesign and commissioning of a rotating test facility simulating a LPT hub cavity system for the investigation of cavity flows in aeroengine
Modal Identification of Bladed Disks by Time-Frequency Analysis of the Non-Synchronous Response
No full textAnalysis of Blade Tip Timing Data From Nonuniformly-Spaced Sensors By Discrete Wavelet Transform
No full textModal Identification of Rotating Blades by Tip Timing and Strain Gauge Measurements in Operating Condition
No full textA wavelet-based intermittency detection technique from PIV investigations in transitional boundary layers
No full textThe transition process of the boundary layer growing over a flat plate with pressure gradient simulating the suction side of a low-pressure turbine blade and elevated free-stream turbulence intensity level has been analyzed by means of PIV and hot-wire measurements. A detailed view of the instantaneous flow field in the wallnormal plane highlights the physics characterizing the complex process leading to the formation of large-scale coherent structures during breaking down of the ordered motion of the flow, thus generating randomized oscillations (i.e., turbulent spots). This analysis gives the basis for the
development of a new procedure aimed at determining the intermittency function describing (statistically) the transition process. To this end, a wavelet-based method has been employed for the identification of the large-scale structures created during the transition process. Successively, a probability density function of these events has been defined so that an intermittency function is deduced. This latter strictly corresponds to the intermittency function of the transitional flow computed trough a classic procedure based on hotwire data. The agreement between the two procedures in the intermittency shape and spot production rate proves the capability of the method in providing the statistical representation of the transition process. The main advantages of the procedure here proposed concern with its applicability to PIV data; it does not require a threshold level to discriminate first- and/or second-order time-derivative of hot-wire time traces (that makes the method not influenced by the operator); and it provides a clear evidence of the connection between the flow physics and the statistical representation of transition based on theory of turbulent spot propagatio
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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