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.
Although the number of implants has increased gradually and consistently over the years to around one million per year globally, there is still far more potential for advancement in the field of dental implantology which is typically growing quickly. This study investigates the effect of nanofiller reinforcement high-performance polymer matrix to enhance mechanical and physical characteristics. Calcium silicate (CS)/Polyetherketoneketone (PEKK) biomedical composite (G0 as a control group) is reinforced with different weight percentages (G1-G4) of tellurium dioxide nanoparticles (TeO2NPs) ( n = 5). This research uses ethanol as a binder for mixing various weight percentages (wt%) of TeO2NPs w
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Poly(L-lactic acid) (PLLA)/poly(caprolactone) (PCL) and two types of organoclay (OMMT) including a fatty amide and ocatdecylamine montmorillonite (FA-MMT and ODA-MMT) were employed to produce polymer nanocomposites by melt blending. Materials were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), elemental analysis, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Mechanical properties were also investigated for these nanocomposites. The nanocomposites showed increasing mechanical properties and thermal stability. XRD results indicated that the materials formed nanocomposites. SEM morphology showed that increasing content of OMMT reduc
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The wall of the esophagus in Mabuya aurata septemaeniata as in high vertebrates consists of four layers, mucosa, submucosa,muscularis and serosa. Mucosa forms many unorganized short and long folds penetrate inside the esophageal cavity. Mucosa contains two sub layers, first one is lining epithelium which includes two types of cells, simple ciliated columnar epithelial cells and goblet cells, second one is lamina properia. Mucosa does not have muscularis mucosa. There is no esophageal glands within esophagus. Many special stains were used as (Periodic Acid Schiff (PAS)) to detect Carbohydrates in goblet cells. Alcian blue were used to detect the amount of goblet cells within lining epithelium. Alcian blue + PAS together confirm that the
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The microdrilling and nanodrilling holes are produced by a Q-switched Nd :YAG laser (1064 nm) interaction with 8009 Al alloy using nanoparticles. Two kinds of nanoparticles were used with this alloy. These nanoparticles are tungsten carbide (WC) and silica carbide (SiC). In this work, the microholes and nanoholes have been investigated with different laser pulse energies (600, 700 and 800)mJ, different repetition rates (5Hz and 10Hz) and different concentration of nanoparticles (90%, 50% and 5% ). The results indicate that the microholes and nanoholes have been achieved when the laser pulse energy is 600 mJ, laser repetition rate is 5Hz, and the concentration of the nanoparticles (for the two types of n
... Show MoreThe present study was carried out onAl-Saqlawiya poultry farm's soil (Anbar, Iraq) for the period of 8 months (November 2018- June 2019). A total of 75 samples of poultry droppings were collectedrandomly. 552 individuals of mite,belonging to 3 orders and 8 families representing 15 species, were found. These species were: Acarus gracilis, Acarus siro, Caloglyphus berlesi, Androlaelaps casalis, Sejus temperaticus, Parasitus paraconsanguineus, Eugamasus butleri, Macrocheles medarius, Macrocheles glaber, Macrocheles muscaedomesticae, Macrocheles matrius, Kleemannia plumosus, Cheyletus eruditus, Cheyletus malaccensis, and Pyemotes herfsi.
The highest population density belonged to order
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Abstract:
Background: The most frequent movement issue seen in clinical practice is tremors. It is known as repetitive, involuntary oscillations. The diagnostic process for tremor patients can be time-consuming and complicated, as the identification of “Essential Tremor” and its distinction from other types of tremor.
Objectives: This study aimed to describe the electrophysiological findings of essential, enhanced physiological, and physiological tremors, using surface electromyography and an accelerometer.
Patients and Methods: The study included 24 patients with essential tremors, 10 patients with enhanced physiological tremors, and 10 patient
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Abstract
The hydrometallurgical method was used to platinum and palladium leaching with aqua regia solution (3HCl: HNO3). The leaching experiments were designed to obtain the optimum conditions by using Taguchi method with 16 experiments at three different factors (time, temperature and solid to liquid ratio), and each factor has four different levels. In this study, leaching the powder sample of catalytic converter that contains platinum and palladium was conducted on the basis of the formation of chloro complexes platinum and palladium (PtCl62-, PdCl42-) with different concentrations in the acidic solution. The optimum condi
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Background: - Carcinoma of the lung has became the most common type of cancer since 1985 & the most common cause of cancer death in both males & females.
Aim of study: - To assess the diagnostic accuracy of bronchial wash cytology & application of immunocytochemical methods, using two tumor markers (low molecular weight cytokeratin & epithelial membrane antigen) for more accurate & precise diagnosis of lung tumors.
Patients, materials and methods: - Fifty fifes suspected lung cancer cases according to their clinicoradiological examinations were included in this study.
Bronchial wash cytology was performed for all the 55 patients. Smears were stained by conventional cytological stain i
Research summary
Westernization is a term not familiar to our scholars at the beginning of the emergence of translation from Western literature, sciences and arts in its detailed form now.
Westernization was not an issue that those Greeks, Persians, Romans, Indians and others worked on translating those sciences and cultures. Rather, it was a process of transferring a new philosophy and logic that had not been previously seen by the Arabs, so they were affected by it in a strange way, to the point of fascination by some of them. For this reason, this research came to clarify these issues and address them within the scientific methodology.