42 research outputs found
Unsteady behavior of corner separation in a compressor cascade: Large eddy simulation and experimental study
Corrosion effects in prestressed concrete beams: Experimental test and non-linear finite element analysis
The aim of this work is to evaluate the decay in the capabilities of corroded pre-stressed concrete beams. For this purpose, an experimental campaign was carried out using 10 beams of 5.4 meters long and a section of 300x150mm, with a high degree of natural non-uniform corrosion. Each considered beam has been tested in different configurations, with 3 and 4 points bending and shear, and the results were analysed using Digital Image Correlation. At the end of the tests the strands have been extracted in order to be catalogued in respect to the corrosion rate. Finally, a modelling procedure has been proposed in order to take into account the effects of different levels of corrosion
RFID based predictive maintenance system for chemical industry
Predictive maintenance is one of the pillar of Industry 4.0, especially for industries integrating machineries subjected to continuous failures which sensibly impact on operations, up to completely stop processes and production. In this perspective, the paper addresses the problem of continuous monitoring of industrial filter press aimed at the early detection blockages/damages of the membranes before avalanche phenomena arise, to prevent the overall failure of the machinery and a prolonged downtime of the plant. The monitoring system includes more than 150 battery-less UHF RFID temperature sensors properly positioned on the inflating pipes of the filter press membranes and a long-range reading architecture comprising two readers and multiple antenna arrays. The system is controlled by an embedded pc unit capable to stream measured data to the SCADA system of the factory via OPC-UA protocol. The paper illustrates the principle of operations, the selection of the components, the deployment of the system and the early operative results
UHF RFID system for the predictive maintenance of a filter press: A real use case
Within the Industry 4.0 context, UHF-RFID-based sensing architectures promise to fill the gap between the physical and digital world, enabling the pervasive measurement of sensing parameters from wireless and battery-less transponders distributed over critical part of machines or embedded in the produced goods. This paper presents the design, the implementation and the commissioning of a complete RFID system aimed at the predictive maintenance of filter-press machinery. The proposed solution includes more than 150 temperature sensors properly positioned on the inflating hoses of the press and interrogated from a network of multiple antenna arrays. The RFID perception layer streams the data via OPC-UA toward the SCADA layer where a cloud-based tool processes the signals at run time to detect anomalies and produces statistics
Unsteady behavior of corner separation in a compressor cascade: Large eddy simulation and experimental study
Spontaneous sphenoid mucocele in a 6-year-old child
Mucoceles of the paranasal sinuses are rare diseases with slow evolution. They are benign, encapsulated, and destructive cysts filled with mucous and covered by respiratory epithelium. among the paranasal sinuses, the sphenoid is affected the least. in children isolated sphenoid mucocele is rarer than adults, usually does not develop in early childhood and typically is not seen until the patient is at least 3 years old. We presented a case of mucocele of the sphenoid sinus in a 6-year-old child. We consider clinical presentation, use of neuroimaging for diagnosis, surgical treatment, and postoperative results. the patient presented with persistent headache and paresis of the oculomotor nerves. Because the symptoms of pediatric sphenoid sinus mucoceles tend to be variable and nonspecific, CT remains the standard for evaluating the disease. In addition, MRI is an essential adjunct in the diagnosis and selection of treatment for suspected tumors of the sphenoid sinus. Sphenoidal mucoceles should be considered as a diagnosis in cases of persistent headache with retrobulbar or vertex location and ocular symptoms. Endoscopic trans nasal marsupialization of the mucocele and antibiotic therapy were performed, leading to complete remission and there was no evidence of recurrence after 12 months follow-up. this suggests that endoscopic trans ostial approach was especially suitable for the management of pediatric benign isolated sphenoid sinus lesions