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3. A Hybrid Genetic-Fuzzy Controller for a 14-inches Astronomical Telescope Tracking

Author

Eid, Doaa, Attia, Abdel-Fattah, Elmasry, Said, and Helmy, Islam

Subjects
Electrical Engineering and Systems Science - Systems and Control, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The performance of on telescope depend strongly on its operating conditions. During pointing the telescope can move at a relatively high velocity, and the system can tolerate trajectory position errors higher than during tracking. On the contrary, during tracking Alt-Az telescopes generally move slower but still in a large dynamic range. In this case, the position errors must be as close to zero as possible. Tracking is one of the essential factors that affect the quality of astronomical observations. In this paper, a hybrid Genetic-Fuzzy approach to control the movement of a two-link direct-drive Celestron telescope is introduced. The proposed controller uses the Genetic algorithm (GA) for optimizing a fuzzy logic controller (FLC) to improve the tracking of the 14-inches Celestron telescope of the Kottamia Astronomical Observatory (KAO). The fuzzy logic input is a vector of the position error and its rate of change, and the output is torque. The GA objective function used here is the Integral Time Absolute Error (ITAE). The proposed method is compared with a conventional Proportional-Differential (PD) controller, an optimized PD controller with a GA, and a Fuzzy controller. The results show the effectiveness of the proposed controller to improve the dynamic response of the overall system., Comment: 10 pages, 3 tables, 9 figures, accepted for publication in Journal of Astronomical Instrumentation (JAI)

Published
2021
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32. The Negative Effect of Epstein-Barr Virus on the Response of Hepatitis C Virus Patients to Interferonribavirin Therapy.

Author

Attia, Abdel-Fattah Mohammed, Madany, Nadia Mohamed Hassan, Madkour, Lamiaa Abd El-Fattah, Maklad, Sahar Zaghlol, and Zayed, Ashgan Mohamed

Subjects
*HEPATITIS C virus, *REVERSE transcriptase polymerase chain reaction, *EPSTEIN-Barr virus
Abstract

Of all viruses causing liver pathology, Epstein-Barr virus (EBV) has been one of the most ubiquitous. Presumably, a co-infection of both EBV and hepatitis C virus (HCV) negatively influences the prognosis of HCV-infected patients. Hence, we endeavoredto estimate the impact of EBV infection on treatment with interferon plus ribavirin in chronic HCV patients. Eighty-four chronic HCV patients and sixteen control subjects (with no symptoms of HCV infection) were enrolled in this study. Viral loads were assessed using reverse transcriptase polymerase chain reaction, while anti-EBV IgM levels were determined by ELISA. Chronic HCV patients with negative EBV IgM exhibited higher response rates (85.7%) to interferon than those with positive EBV IgM (62%). Furthermore, HCV RNA load was remarkably higher in EBV-seropositive patients (with a P-value of 0.0001). Chronic HCV infection cannot be considered in isolation; as other pathogens such as EBV may have far-ranging effects against the disease prognosis. We concluded that EBV co-infection can deteriorate the response to interferon in patients with chronic HCV infection, and that EBV could enhance the replication of HCV. Accordingly, EBV treatment should be considered when designing specific protocols for treatment of such patients. [ABSTRACT FROM AUTHOR]

Published
2019
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