This paper presents L1-adaptive controller for controlling uncertain parameters and time-varying unknown parameters to control the position of a DC servomotor. For the purpose of comparison, the effectiveness of L1-adaptive controller for position control of studied servomotor has been examined and compared with another adaptive controller; Model Reference Adaptive Controller (MRAC). Robustness of both L1-adaptive controller and model reference adaptive controller to different input reference signals and different structures of uncertainty were studied. Three different types of input signals are taken into account; ramp, step and sinusoidal. The L1-adaptive controller ensured uniformly bounded transient and asymptotic tracking for both system's input and output signals, simultaneously with asymptotic tracking. Simulations of a DC servomotor with time-varying friction and disturbance are presented to verify the theoretical findings.
We prepared polythiophene (PTH) with single wall carbon nanotube (SWCNT) nanocomposite thin films for Nitrogen dioxide (NO2) gas sensing applications. Thin films were synthesized via electrochemical polymerization method onto (Indium tin oxide) ITO coated glass substrate of thiophene monomer with magnesium perchlorate and different concentration from SWCNT (0.012 and 0.016) % in the presence130mL of Acetonitrile used. X-ray diffraction (XRD), Field Emission Scanning Electron microscopy (FE-SEM), Atomic Force Microscope (AFM) and Fourier Transform Infrared Spectroscopy (FT-IR) were used to characterized these nanocomposite thin films. The response of these nanocomposite for NO2 gas was evaluated via monitoring the change
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Molasse medium containing different concentrations of (NH4)2 SO4, (NH4)3 PO4, urea, KCI, and P2O5 were compared with the medium used for commercial production of C. utilis in a factory south of Iraq. An efficient medium, which produced 19. 16% dry wt. and 5. 78% protein, was developed. The effect of adding various concentrations of micronutrients (FeSO4, 7T20, MnSO4. 7H20, ZnSO4. 7E20) was also studied. Results showed that FeSo4. 7H20 caused a noticeable increase in both dry wt. and protein content of the yeast.
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This paper reports experimental and computational fluid dynamics (CFD) modelling studies to investigate the effect of the swirl intensity on the heat transfer characteristics of conventional and swirl impingement air jets at a constant nozzle-to-plate distance ( L = 2 D). The experiments were performed using classical twisted tape inserts in a nozzle jet with three twist ratios ( y = 2.93, 3.91, and 4.89) and Reynolds numbers that varied from 4000 to 16000. The results indicate that the radial uniformity of Nusselt number (Nu) of swirl impingement air jets (SIJ) depended on the values of the swirl intensity and the air Reynolds number. The results also revealed that the SIJ that was fitted with an insert of y = 4.89, which correspo
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يؤدي عرض معلومات مضللة او محرفة ضمن القوائم المالية والتي تعد أهم مصادر المعلومات الموثوقة التي يُعول عليها لاتخاذ القرارات السليمة الى عدم قدرتها على عكس نتيجة النشاط والمركز المالي لها او اعمال الوحدة الاقتصادية لتلك الفترات الزمنية بصورة صادقة وعادلة نتيجة لنوعية المعلومات المفصح عنها في القوائم المالية لذلك زاد الاهتمام بتطوير الممارسات المحاسبية لتتضمن افصاحات كافية بغرض اعطائهم صورة صادقة وعادلة
... Show MoreThe objective of the current research is to identify the effective of the suggested instructional design that based on the teaching strategy for understanding in achievement for students(girls) of mathematics in the fifth grads secondary school. To achieve the research goal, the empirical research method is depended. In this method a realistic empirical design pre-test of two equivalent sets to determine the students’ grade is used. The following zero hypotheses is formulated “There is no statistical difference for the faction at 0.05 between the mean grad for the students of the empirical group who studied the subject using the Instructional design based on the teaching strategy for understanding and those who studied the same subje
... Show MoreThis topic is considered to be of a high degree of importance to every Muslim, and its importance is due to the fact that monotheism is:
Prove that God Almighty is the God who created everything and everything opposite to monotheism is polytheism, and it is taking other than God Almighty as a deity.
Therefore, we have to know the concept of God. If he is known, then he knows the concept of monotheism and the concept of polytheism
The present paper talks about balance between two poems which are the Nouniya for Ibn Zaidoun and Andalusia for Ahmed Shawqi. This study is not claimed to be the first of its kind but we found some artistic aspects that deserve to stop at them. This what makes the two the focus of critics and scholars as well in addition to their emphasis on the unity of the human feelings and immortality through the poet's ability to employ those feelings and emotions in a way that it can express the human soul in every time and place. That is what we believe Ibn Zaidoun had reached in his poem. Therefore, the present paper has come into the conclusion that Ibn Zaydoon's Nouniya is better than Shawqi's Andalusia due to what we got through reading and an
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