Forecasting of ionospheric electron density trough for characterization of aerospace medium

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2009

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Kocabaş, Zeynep

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Modeling the ionosphere, where the effects of solar dynamo becomes more effective to space based and ground borne activities, has an undeniable importance for telecommunication and navigation purposes. Mid-latitude electron density trough is an interesting phenomenon in characterizing the behavior of the ionosphere, especially during disturbed conditions. Modeling the mid-latitude electron density trough is a very popular research subject which has been studied by several researchers until now. In this work, an operational technique has been developed for a probabilistic space weather forecast using fuzzy modeling and computer based detection of trough in two steps. First step is to detect the appropriate geomagnetical conditions for trough formation, depending on the values of 3-h planetary K index (Kp), magnetic season, latitude and local time, by using fuzzy modeling technique. Once the suitable geomagnetic conditions are detected, second step is to find the lower latitude position (LLP) and minimum position (MP) of the observed trough being two main identifiers of the mid-latitude electron density trough. A number of case studies were performed on ARIEL 4 satellite data, composed of different geomagnetic, annual and diurnal characteristics. The results obtained from fuzzy modeling show that the model is able to detect the appropriate conditions for trough occurrence and the trough shape was effectively identified for each selected case by using the predefined descriptions of mid-latitude electron density trough. The overall results are observed to be promising.

Subject Keywords

Aerospace engineering., Aeronautical engineering.

URI

http://etd.lib.metu.edu.tr/upload/12610445/index.pdf
https://hdl.handle.net/11511/18419

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

Z. Kocabaş, “Forecasting of ionospheric electron density trough for characterization of aerospace medium,” M.S. - Master of Science, Middle East Technical University, 2009.