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.
DBN Rashid, Astra Salvensis, 2018 - Cited by 1
The present paper respects 'inversion' as a habit of arranging the language of modern English and Arabic poetry . Inversion is a significant phenomenon generally in modern literature and particularly in poetry that it treats poetic text as it is a violator to the ordinary text. The paper displays the common patterns and functions of inversion which are spotted in modern English and Arabic poetry in order to show aspects of similarities and differences in both languages. It concludes that inversion is most commonly used in English and Arabic poetry in which it may both satisfy the demands of sound correspondence and emphasis. English and Arabic poetic languages vary in extant to their manipulation of inverted styles as they show changeable f
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The study was performed to isolate and identify the Myxococcus
xanthus from (50) samples of grave soils .Special growth conditions had been used to support the growth of M.
xanthus and to suppressed the growth of other microorganisms like (Drying , High concentration of antibiotics and specific growth media)
M. . xanthus isolates had been subjected to the morphological, cultural and biochemical examinations for identification . Results obtaind could be summarized as follows : 1. Myxobacteria were found as normal flora inhabitants of the arid soils. 2. Ten local isplates of M. xanthus out of (50) soil samples were isolated
A study carried out on ceramic material made at (a-Al2O3) doped with MgO (0.5 , 0.3 , 0.2,0.1)%,with particle size at 63mm.
A Hydraulic press of 5kn at diameter of 2cm.A nnalelling at 1500Co and 6 hrs still to see the effect on the changes of the dielectric material. With frequency range at (1K – 1M) Hz. And the result show that at percentage of 0.5% of MgO, the real dielectric material decreased with the increased frequency
The main problem established by a discovery of a thyroid nodule is to discriminate between a benign and malignant lesion. Differential diagnosis between follicular thyroid cancer (FTC) and benign follicular thyroid adenoma (FTA) is a great challenge for even an experienced pathologist and requires special effort. A developing number of some encouraging IHC markers for the differential diagnosis of thyroid lesions have emerged, including, Hector Battifora mesothelial (HBME-1) and galectin-3 (Gal-3). There was significant positive correlation between Galectin-3 and HBME-1 in follicular carcinoma and follicular variant of papillary carcinoma (r= 0.380, P= 0.041) and (r= 0.315, P=0.047) respectively. There was no significant correlation between
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Pseudomonas aeruginosa produces an extracellular bioï¬lm matrix that consists of nucleic acids, exopolysaccharides, lipid vesicles, and proteins. Alginate, Psl and Pel are three exopolysaccharides that constitute the main components in biofilm matrix, with many biological functions attributed to them, especially concerning the protection of the bacterial cell from antimicrobial agents and immune responses. A total of 25 gentamicin-resistant P. aeruginosa selected isolates were enrolled in this study. Biofilm development was observed in 96% of the isolates. In addition, the present results clarified the presence of pelA and pslA in all the studied isolates. The expression of these genes was very low. Even though all biof
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The knowledge related with lexical items can be realized as including relations of meaning a cross words. Words that share a similarity of meaning are called to be synonymous, and words that share a contrary of meaning are called to be antonymous. Both of them are universal linguistic phenomenon that exist in terms of linguistic system of every language. The present study aims at finding out areas of difficulty that Iraqi EFL learners encounter in the use of synonymy and antonymy, both on the recognition and production levels. Also tries to detect the main reasons behind such difficulties. A diagnostic test of two parts, namely, recognition and production, is designed. The test is built to include two linguistic phenomenon which are: synony
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The process for preparing activated carbon (AC) made from tea residue was described in this paper. Investigated were the physicochemical characteristics and adsorption efficiency of the produced AC. Activation with potassium hydroxide (KOH) and carbonization at 350 °C are the two key steps in the manufacturing of AC. The activated carbon was used to adsorb Tetracycline (TC). Different parameters were studied at room temperature to show their effects on the adsorption efficiency of TC. These parameters are the initial concentration of adsorbate TC, solution acidity pH, time of adsorption, and adsorbent dosage. The prepared active carbon was characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microsc
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