Browse Topic: Fuzzy logic
In the last decades there have been many temporary engine failures, engine-related events and erroneous airspeed indication measurements that occurred by a phenomenon known as Ice Crystal Icing (ICI). This type of icing mainly occurs in high altitudes close to tropical convection in areas with a high concentration of ice crystals. Direct measurements or in-situ pilot observations of ICI that could be used as a warning to other air-traffic are rare to nearly non-existent. To detect those dangerous high Ice Water Content (IWC) areas with already existing airborne measurement instruments, Lufthansa analyzed observed Total Air Temperature (TAT) anomalies and used a self-developed search algorithm, depicting those TAT anomalies that are related to ice crystal icing events. To optimize the flight route for dispatchers several hours before the flight, e.g. for long distance flights through the intertropical convergence zone (ITCZ), reliable forecasts to identify hazardous high IWC regions are
Humanity has been interested in magnetism for over 300 years. Many authors have studied the use of applied magnetism to change the properties of products and expand the use of magnetic processing in ship repair production [1, 2]. Experience shows that magnetic pulse processing (MPP) is a simple and economical way to increase the durability of metal-cutting tools, increase the resource of the most worn parts of machines and mechanisms, and increase the durability of friction units, assembly units, and structures during their repair and manufacture. MPP has a number of advantages: simplicity of electromagnetic energy concentration on the product, its rapid accumulation by the material of the working elements of the part, and the efficiency of improving the operational characteristics (processing time is 0.3 ... 2.0 s with insignificant energy consumption). The indicated advantages of magnetic processing of products in comparison with other methods of hardening have been repeatedly
Epicyclic geartrains are often preferred in heavy-duty machinery owing to their abilities such as transmitting large amounts of power with minimal loss, good load sharing capacity, large reduction ratios, and compact design. Machinery employing such complex geartrains need an effective monitoring system to predict gear failure at an early stage which prevents catastrophic failure. In this work, vibration signal of the geartrain is acquired using an accelerometer under various gear fault conditions such as healthy gear, defect in sun gear, defect in planet gear, defect in ring gear, defect in both sun and planet gears respectively. Then, statistical characteristics or features such as mean, median, mode, variance, skewness, kurtosis, standard error, standard deviation, maximum and minimum, of the time domain vibration signals are extracted. Afterward, a decision tree algorithm is used to select the most useful statistical features. These selected features form input to the fuzzy
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